FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Lapenta, G Markidis, S Marocchino, A Kaniadakis, G AF Lapenta, Giovanni Markidis, Stefano Marocchino, Alberto Kaniadakis, G. TI Relaxation of relativistic plasmas under the effect of wave-particle interactions SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic rays; plasmas; relativity; waves ID ELECTRON; INSTABILITY; TURBULENCE; HOLES AB We simulate the acceleration of electrons to relativistic energies due to the interaction of electrons with waves generated by longitudinal (i. e., electrostatic) streaming instabilities in plasmas. Two equal systems undergoing a streaming instability evolve, one according to the classical Newton's law and one according to the special relativity dynamics equation. The system that obeys Newton's law relaxes to a Maxwellian equilibrium distribution. In the case of the relativistic dynamics, the equilibrium distribution exhibits peaks in the phase space at high momenta and a larger number of particles at high energies. This steady electron population at higher energies could explain power-law energy distribution in many plasma physics and astrophysical systems. C1 Katholieke Univ Leuven, Dept Wiskunde, Ctr Plasma Astrofys, B-3001 Heverlee, Belgium. Los Alamos Natl Lab, Belgium & Plasma Theory Grp, Los Alamos, NM USA. Univ Illinois, Dept Nucl Plasma & Radiol Engn, Urbana, IL 61801 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London, England. Politecn Torino, Dipartimento Fis, Turin, Italy. RP Lapenta, G (reprint author), Katholieke Univ Leuven, Dept Wiskunde, Ctr Plasma Astrofys, Celestijnenlaan 200B, B-3001 Heverlee, Belgium. RI Marocchino, Alberto/E-3571-2016; OI Marocchino, Alberto/0000-0002-5287-8355; Lapenta, Giovanni/0000-0002-3123-4024 NR 25 TC 30 Z9 30 U1 2 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD SEP 10 PY 2007 VL 666 IS 2 BP 949 EP 954 DI 10.1086/520326 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 208FR UT WOS:000249305700026 ER PT J AU Dib, R Kaspi, VM Gavriil, FP AF Dib, Rim Kaspi, Victoria M. Gavriil, Fotis P. TI 10 years of RXTE monitoring of the anomalous X-ray pulsar 4U 0142+61: Long-term variability SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : individual (4U 0142+61); stars : neutron; X-rays : stars ID PROPORTIONAL COUNTER ARRAY; SOFT GAMMA REPEATERS; 1RXS J170849.0-400910; NEUTRON-STAR; 1E 2259+586; CHANDRA OBSERVATIONS; SPIN-DOWN; EMISSION; GLITCH; OUTBURST AB We report on 10 years of monitoring of the 8.7 s anomalous X-ray pulsar 4U 0142+ 61 using the Rossi X-Ray Timing Explorer (RXTE). This pulsar exhibited stable rotation from 2000 March until 2006 February; the rms phase residual for a spin-down model, which includes nu , nu, and nu, is 2.3%. We report a possible phase-coherent timing solution valid over a 10 yr span extending back to 1996 March. A glitch may have occurred between 1998 and 2000, but is not required by the existing timing data. The pulse profile has been evolving since 2000. In particular, the dip of emission between its two peaks got shallower between 2002 and 2006, as if the profile were evolving back to its pre-2000 morphology, following an earlier event, which possibly also included the glitch suggested by the timing data. These profile variations are seen in the 2-4 keV band, but not in 6-8 keV. We also detect a slow increase in the pulsed flux between 2002 May and 2004 December, such that it has risen by 36% +/- 3% over 2.6 yr in the 2-10 keV band. The pulsed flux variability and the narrowband pulse profile changes present interesting challenges to aspects of the magnetar model. C1 McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Oak Ridge Associated Univ, Oak Ridge, TN USA. RP Dib, R (reprint author), McGill Univ, Dept Phys, 3600 Univ St, Montreal, PQ H3A 2T8, Canada. NR 49 TC 42 Z9 43 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD SEP 10 PY 2007 VL 666 IS 2 BP 1152 EP 1164 DI 10.1086/519726 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 208FR UT WOS:000249305700042 ER PT J AU Blake, CH Charbonneau, D White, RJ Marley, MS Saumon, D AF Blake, Cullen H. Charbonneau, David White, Russel J. Marley, Mark S. Saumon, Didier TI Multiepoch radial velocity observations of L dwarfs SO ASTROPHYSICAL JOURNAL LA English DT Article DE planetary systems; stars : low-mass; brown dwarfs; techniques : radial velocities ID EXTRASOLAR GIANT PLANETS; BROWN DWARFS; ULTRACOOL DWARFS; ROTATION; SEARCH; MASSES; MODEL; EMISSION; SPECTRA; OBJECTS AB We report on the development of a technique for precise radial velocity measurements of cool stars and brown dwarfs in the near infrared. Our technique is analogous to the iodine (I-2) absorption cell method that has proven so successful in the optical regime. We rely on telluric CH4 absorption features to serve as a wavelength reference, relative to which we measure Doppler shifts of the CO and H2O features in the spectra of our targets. We apply this technique to high-resolution (R approximate to 50; 000) spectra near 2.3 mu m of nine L dwarfs taken with the Phoenix instrument on Gemini South and demonstrate a typical precision of 300 m s(-1). We conduct simulations to estimate our expected precision and show that our performance is currently limited by the signal-to-noise ratio (S/N) of our data. We present estimates of the rotational velocities and systemic velocities of our targets. With our current data we are sensitive to companions with M sin i > 2 M-J in orbits with periods less than 3 days. We identify no companions in our current data set. Future observations with improved S/N should result in radial velocity precision of 100 m s(-1) for L dwarfs. C1 Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Alabama, Dept Phys, Huntsville, AL 35899 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Blake, CH (reprint author), Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA. RI Marley, Mark/I-4704-2013; OI Charbonneau, David/0000-0002-9003-484X NR 51 TC 52 Z9 52 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD SEP 10 PY 2007 VL 666 IS 2 BP 1198 EP 1204 DI 10.1086/520124 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 208FR UT WOS:000249305700046 ER PT J AU Hoegg, S Boore, JL Kuehl, JV Meyer, A AF Hoegg, Simone Boore, Jeffrey L. Kuehl, Jennifer V. Meyer, Axel TI Comparative phylogenomic analyses of teleost fish Hox gene clusters: lessons from the cichlid fish Astatotilapia burtoni SO BMC GENOMICS LA English DT Article ID WHOLE-GENOME DUPLICATION; RAY-FINNED FISH; MOLECULAR EVOLUTION; REGULATORY ELEMENTS; NONCODING SEQUENCES; PROVIDES EVIDENCE; MODEL SYSTEMS; VERTEBRATE; EXPRESSION; ZEBRAFISH AB Background: Teleost fish have seven paralogous clusters of Hox genes stemming from two complete genome duplications early in vertebrate evolution, and an additional genome duplication during the evolution of ray-finned fish, followed by the secondary loss of one cluster. Gene duplications on the one hand, and the evolution of regulatory sequences on the other, are thought to be among the most important mechanisms for the evolution of new gene functions. Cichlid fish, the largest family of vertebrates with about 2500 species, are famous examples of speciation and morphological diversity. Since this diversity could be based on regulatory changes, we chose to study the coding as well as putative regulatory regions of their Hox clusters within a comparative genomic framework. Results: We sequenced and characterized all seven Hox clusters of Astatotilapia burtoni, a haplochromine cichlid fish. Comparative analyses with data from other teleost fish such as zebrafish, two species of pufferfish, stickleback and medaka were performed. We traced losses of genes and microRNAs of Hox clusters, the medaka lineage seems to have lost more microRNAs than the other fish lineages. We found that each teleost genome studied so far has a unique set of Hox genes. The hoxb7a gene was lost independently several times during teleost evolution, the most recent event being within the radiation of East African cichlid fish. The conserved non-coding sequences (CNS) encompass a surprisingly large part of the clusters, especially in the HoxAa, HoxCa, and HoxDa clusters. Across all clusters, we observe a trend towards an increased content of CNS towards the anterior end. Conclusion: The gene content of Hox clusters in teleost fishes is more variable than expected, with each species studied so far having a different set. Although the highest loss rate of Hox genes occurred immediately after whole genome duplications, our analyses showed that gene loss continued and is still ongoing in all teleost lineages. Along with the gene content, the CNS content also varies across clusters. The excess of CNS at the anterior end of clusters could imply a stronger conservation of anterior expression patters than those towards more posterior areas of the embryo. C1 [Hoegg, Simone; Meyer, Axel] Univ Konstanz, Dept Biol, Lehrstuhl Evolut Biol & Zool, D-78457 Constance, Germany. [Boore, Jeffrey L.; Kuehl, Jennifer V.] Univ Calif Berkeley, Program Evolutionary Genom, DOE Joint Genome Inst, Berkeley, CA 94720 USA. [Boore, Jeffrey L.; Kuehl, Jennifer V.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Boore, Jeffrey L.] SymBio Corp, Menlo Pk, CA 94025 USA. [Boore, Jeffrey L.] Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Meyer, A (reprint author), Univ Konstanz, Dept Biol, Lehrstuhl Evolut Biol & Zool, D-78457 Constance, Germany. EM Simone.Isabel.Hoegg@uni-konstanz.de; jboore@sym-bio.com; JVKuehl@lbl.gov; Axel.Meyer@uni-konstanz.de RI Meyer, Axel/C-9826-2009 OI Meyer, Axel/0000-0002-0888-8193 NR 98 TC 51 Z9 53 U1 1 U2 8 PU BIOMED CENTRAL LTD PI LONDON PA 236 GRAYS INN RD, FLOOR 6, LONDON WC1X 8HL, ENGLAND SN 1471-2164 J9 BMC GENOMICS JI BMC Genomics PD SEP 10 PY 2007 VL 8 AR 317 DI 10.1186/1471-2164-8-317 PG 16 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 240CT UT WOS:000251565300001 PM 17845724 ER PT J AU Anderson, SG Gibson, DJ Hartemann, FV Jacob, JS Tremaine, AM Lim, JK Frigola, P Rosenzweig, JB Travish, G AF Anderson, S. G. Gibson, D. J. Hartemann, F. V. Jacob, J. S. Tremaine, A. M. Lim, J. K. Frigola, P. Rosenzweig, J. B. Travish, G. TI Production of femtosecond pulses and micron beam spots for high brightness electron beam applications SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article; Proceedings Paper CT 46th Workshop on Physics and Applications of High Brightness Electon Beams CY OCT 09-14, 2005 CL Erice, ITALY SP ICFA ID ACCELERATION; SCATTERING; RADIATION; PLASMA AB Current and future applications of high brightness electron beams, which include advanced accelerators and beam-radiation interactions require both transverse and longitudinal beam sizes on the order of tens of microns. Ultra-high density beams may be produced at moderate energy (50 MeV) by compression and subsequent strong focusing of low emittance, photoinjector sources. We describe the implementation of this method used at the PLEIADES inverse-Compton scattering (ICS) x-ray source at LLNL in which the photoinjector-generated beam has been compressed to 300 fsec rms duration using the velocity bunching technique and focused to 20 mu m rms size using an extremely high gradient, permanent magnet quadrupole focusing system. C1 [Anderson, S. G.; Gibson, D. J.; Hartemann, F. V.; Jacob, J. S.; Tremaine, A. M.] Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. [Lim, J. K.; Frigola, P.; Rosenzweig, J. B.; Travish, G.] Univ Calif Los Angeles, Los Angeles, CA 90095 USA. RP Anderson, SG (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave, Livermore, CA 94551 USA. RI Travish, Gil/H-4937-2011 OI Travish, Gil/0000-0002-4787-0949 NR 21 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X EI 1793-656X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD SEP 10 PY 2007 VL 22 IS 22 BP 3726 EP 3735 DI 10.1142/S0217751X0703738X PG 10 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 242GT UT WOS:000251713300003 ER PT J AU Bane, KLF AF Bane, K. L. F. TI Wakefields of sub-picosecond electron bunches SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article; Proceedings Paper CT 46th Workshop on Physics and Applications of High Brightness Electon Beams CY OCT 09-14, 2005 CL Erice, ITALY SP ICFA ID IMPEDANCE AB We discuss wakefields excited by short bunches in accelerators. In particular, we review some of what has been learned in recent years concerning diffraction wakes, roughness impedance, coherent synchrotron radiation wakes, and the resistive wall wake, focusing on analytical solutions where possible. As examples, we apply formulas for these wakes to various parts of the Linac Coherent Light Source (LCLS) project. The longitudinal accelerator structure wake of the SLAG linac is an important ingredient in the LCLS bunch compression process. Of the wakes in the undulator region, the dominant one is the resistive wall wake of the beam pipe. C1 Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Bane, KLF (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. EM kbane@slac.stanford.edu NR 48 TC 4 Z9 4 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD SEP 10 PY 2007 VL 22 IS 22 BP 3736 EP 3758 DI 10.1142/S0217751X07037391 PG 23 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 242GT UT WOS:000251713300004 ER PT J AU Ben-Zvi, I Rao, T Burrill, A Chang, X Grimes, J Rank, J Segalov, Z Smedley, J AF Ben-Zvi, I. Rao, T. Burrill, A. Chang, X. Grimes, J. Rank, J. Segalov, Z. Smedley, J. TI Diamond secondary emitter SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article; Proceedings Paper CT 46th Workshop on Physics and Applications of High Brightness Electon Beams CY OCT 09-14, 2005 CL Erice, ITALY SP ICFA ID POLYCRYSTALLINE DIAMOND; FILMS AB We present the design and experimental progress on the diamond secondary emitter as an electron source for high average power injectors. The design criteria for average currents up to 1 A and charge up to 20 nC are established. Secondary Electron yield (SEY) exceeding 200 in transmission mode and 50 in emission mode have been measured. Preliminary results on the design and fabrication of the self contained capsule with primary electron source and secondary electron emitter will also be presented. C1 [Ben-Zvi, I.; Rao, T.; Burrill, A.; Chang, X.; Grimes, J.; Rank, J.; Segalov, Z.; Smedley, J.] Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ben-Zvi, I (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 16 TC 3 Z9 3 U1 0 U2 3 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD SEP 10 PY 2007 VL 22 IS 22 BP 3759 EP 3775 DI 10.1142/S0217751X07037408 PG 17 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 242GT UT WOS:000251713300005 ER PT J AU Huang, Z Stupakov, G Reiche, S AF Huang, Z. Stupakov, G. Reiche, S. TI Emittance limitation of a conditioned beam in a strong focusing FEL undulator SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article; Proceedings Paper CT 46th Workshop on Physics and Applications of High Brightness Electon Beams CY OCT 09-14, 2005 CL Erice, ITALY SP ICFA ID FREE-ELECTRON LASERS; WIGGLERS AB Various methods have been proposed to condition an electron beam in order to reduce its emittance effect and to improve the short-wavelength free electron laser (FEL) performance. In this paper, we show that beam conditioning does not result in a complete elimination of the emittance effect in an alternating-gradient focusing FEL undulator. Using a one-dimensional model and a three-dimensional simulation code, we derive a criteria for the emittance limitation of a perfectly conditioned beam that depends on the focusing structure. C1 [Huang, Z.; Stupakov, G.] Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. [Reiche, S.] Univ Calif Los Angeles, Los Angeles, CA 90095 USA. RP Huang, Z (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 17 TC 1 Z9 1 U1 1 U2 3 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD SEP 10 PY 2007 VL 22 IS 22 BP 3826 EP 3837 DI 10.1142/S0217751X07037457 PG 12 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 242GT UT WOS:000251713300010 ER PT J AU Krafft, GA AF Krafft, Geoffrey A. TI High brightness beam applications: Energy recovered linacs SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article; Proceedings Paper CT 46th Workshop on Physics and Applications of High Brightness Electon Beams CY OCT 09-14, 2005 CL Erice, ITALY SP ICFA ID FREE-ELECTRON LASER; OPERATION AB In the first part of the paper some general statements are made regarding applications suitable for utilizing energy recovered linacs (ERLs) by contrasting their potential performance to that of single pass linacs and storage rings. As a result of their potential for extremely good beam quality in combination with high average beam current, ERLs have been used and considered as drivers of both free electron laser and partially coherent photon sources, from THz through X-rays; as a suitable technology for high energy electron cooling; and as a continuous or semi-continuous electron beam source for high energy colliders. At present, beam requirements tend to be highly matched to end use requirements. By reviewing some of the many examples which have either been reduced to practice, or are being explored presently, one can develop an appreciation for the wide range of parameters being considered in ERL applications. C1 Ctr Adv Studies Accelerators, Jefferson Lab, Newport News, VA 23606 USA. RP Krafft, GA (reprint author), Ctr Adv Studies Accelerators, Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 23 TC 0 Z9 0 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD SEP 10 PY 2007 VL 22 IS 22 BP 3852 EP 3863 DI 10.1142/S0217751X07037470 PG 12 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 242GT UT WOS:000251713300012 ER PT J AU Limborg-Deprey, C Tomizawa, H AF Limborg-Deprey, C. Tomizawa, H. TI Maximizing brightness in photoinjectors SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article; Proceedings Paper CT 46th Workshop on Physics and Applications of High Brightness Electon Beams CY OCT 09-14, 2005 CL Erice, ITALY SP ICFA AB If the laser pulse driving photoinjectors could be arbitrarily shaped, the emittance growth induced by space charge effects could be totally compensated for. In particular, for RF guns, the photo-electron distribution leaving the cathode should be close to a uniform distribution contained in a 3D-ellipsoid contour. For photo-cathodes which have very fast emission times, and assuming a perfectly uniform emitting surface, this could be achieved by shaping the laser in a pulse of constant fluence and limited in space by a 3D-ellipsoid contour. Simulations show that in such conditions, with the standard linear emittance compensation, the emittance at the end of the photo-injector beamline approaches the minimum value imposed by the cathode emittance. Brightness, which is expressed as the ratio of peak current over the product of the two transverse emittance, seems to be maximized for small charges. Numerical simulations also show that for very high charge per bunch (10nC), emittances as small as 2 mm-mrad could be reached by using 3D-ellipsoidal laser pulses in an S-Band gun. The production of 3D-ellipsoidal pulses is very challenging, but seems worthwhile the effort. We briefly discuss some of the present ideas and difficulties of achieving such pulses. C1 [Limborg-Deprey, C.] SLAC, Menlo Pk, CA 94025 USA. [Tomizawa, H.] SPring 8, Mikazuki, Hyogo 6795198, Japan. RP Limborg-Deprey, C (reprint author), SLAC, 2275 Sand Hill Rd,MS18, Menlo Pk, CA 94025 USA. EM limborg@slac.stanford.edu NR 18 TC 1 Z9 1 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD SEP 10 PY 2007 VL 22 IS 22 BP 3864 EP 3881 DI 10.1142/S0217751X07037482 PG 18 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 242GT UT WOS:000251713300013 ER PT J AU Thompson, MC Badakov, H Rosenzweig, JB Travish, G Edwards, H Fliller, R Kazakevich, GM Piot, P Santucci, J Li, J Tikhoplav, R AF Thompson, M. C. Badakov, H. Rosenzweig, J. B. Travish, G. Edwards, H. Fliller, R. Kazakevich, G. M. Piot, P. Santucci, J. Li, J. Tikhoplav, R. TI Results from the UCLA/FNPL underdense plasma lens experiment SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article; Proceedings Paper CT 46th Workshop on Physics and Applications of High Brightness Electon Beams CY OCT 09-14, 2005 CL Erice, ITALY SP ICFA AB A gaussian underdense plasma lens with peak density 5 x 10(12) cm(-3) and a full width half maximum (FWHM) length of 2.2 cm has been used to focus a relativistic electron beam. This plasma lens is equivalent in strength to a quadrupole magnet with a 150 T/m field gradient. The lens focused a 15 MeV, 16 nC electron beam with initial dimensions sigma(x,y) approximate to 650 mu m and sigma(z) approximate to 6.5 mm onto an optical transition radiation (OTR) screen similar to 2 cm downstream of the lens. The average transverse area of the plasma focused electron beam was typically demagnified by a factor of 23. The evolution of the beam envelope in the area near the beam waist was measured for both round beams and asymmetric beams with x:y aspect ratios as large as 1:5. The light from the OTR screen in the round beam case was also imaged into a streak camera in order to directly measure the correlation between z and sigma(r) within the beam. C1 [Thompson, M. C.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. [Thompson, M. C.; Badakov, H.; Rosenzweig, J. B.; Travish, G.] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. [Edwards, H.; Fliller, R.; Kazakevich, G. M.; Piot, P.; Santucci, J.] Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. [Li, J.; Tikhoplav, R.] Univ Rochester, Rochester, NY 14627 USA. RP Thompson, MC (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM thompson93@llnl.gov RI Travish, Gil/H-4937-2011 OI Travish, Gil/0000-0002-4787-0949 NR 13 TC 0 Z9 0 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD SEP 10 PY 2007 VL 22 IS 22 BP 3979 EP 3987 DI 10.1142/S0217751X0703755X PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 242GT UT WOS:000251713300020 ER PT J AU Zolotorev, M Commins, ED Heifets, S Sannibale, F AF Zolotorev, M. Commins, E. D. Heifets, S. Sannibale, F. TI Proposal for a high-brightness pulsed electron source SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article; Proceedings Paper CT 46th Workshop on Physics and Applications of High Brightness Electon Beams CY OCT 09-14, 2005 CL Erice, ITALY SP ICFA ID RYDBERG ATOMS; CESIUM AB We propose a novel scheme for a high-brightness pulsed electron source, which has the potential for many useful applications in electron microscopy, inverse photo-emission, low energy electron scattering experiments, and electron holography. A description of the proposed scheme is presented. C1 [Zolotorev, M.; Sannibale, F.] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. [Commins, E. D.] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. [Heifets, S.] Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Zolotorev, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 6 TC 0 Z9 0 U1 0 U2 2 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD SEP 10 PY 2007 VL 22 IS 22 BP 4006 EP 4012 DI 10.1142/S0217751X07037585 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 242GT UT WOS:000251713300023 ER PT J AU Koutsourelakis, PS AF Koutsourelakis, P. S. TI Stochastic upscaling in solid mechanics: An excercise in machine learning SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE random; heterogeneity; homogenization; upscaling; information theory; rate-distortion; quantization ID FINITE-ELEMENT-METHOD; ELLIPTIC PROBLEMS; RANDOM-MEDIA; HOMOGENIZATION; COMPUTATION AB This paper presents a consistent theoretical and computational framework for upscaling in random microstructures. We adopt an information theoretic approach in order to quantify the informational content of the microstructural details and find ways to condense it while assessing quantitatively the approximation introduced. In particular, we substitute the high-dimensional microscale description by a lower-dimensional representation corresponding for example to an equivalent homogeneous medium. The probabilistic characteristics of the latter are determined by minimizing the distortion between actual macroscale predictions and the predictions made using the coarse model. A machine learning framework is essentially adopted in which a vector quantizer is trained using data generated computationally or collected experimentally. Several parallels and differences with similar problems in source coding theory are pointed out and an efficient computational tool is employed. Various applications in linear and non-linear problems in solid mechanics are examined. Published by Elsevier Inc. C1 Lawrence Livermore Natl Lab, Elect Engn Technol Div, Livermore, CA 94551 USA. RP Koutsourelakis, PS (reprint author), Lawrence Livermore Natl Lab, Elect Engn Technol Div, L-229, Livermore, CA 94551 USA. EM koutsourelakis2@llnl.gov OI Koutsourelakis, Phaedon-Stelios/0000-0002-9345-759X NR 31 TC 11 Z9 11 U1 3 U2 10 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD SEP 10 PY 2007 VL 226 IS 1 BP 301 EP 325 DI 10.1016/j.jcp.2007.04.012 PG 25 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 217GN UT WOS:000249936500014 ER PT J AU Xie, XY Musson, LC Pasquali, M AF Xie, Xueying Musson, Lawrence C. Pasquali, Matteo TI An isochoric domain deformation method for computing steady free surface flows with conserved volumes SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE domain deformation method; free surface flows; free-boundary problems; isochoric mapping method; finite element method ID MOVING BOUNDARY-PROBLEMS; FINITE-ELEMENT AB The domain deformation method has been applied successfully to steady state free surface flows where the volume of the flow domain is unknown [V.F. de Almeida, Gas-liquid counterflow through constricted passages, Ph.D. thesis, University of Minnesota, Minneapolis, MN 1995; P.A. Sackinger, P.R. Schunk, R.R. Rao, A Newton-Raphson pseudo-solid domain mapping technique for free and moving boundary problems: a finite element implementation, J. Comput. Phys. 125 (1996) 83-103; L.C. Musson, Two-layer slot coating, Ph.D. thesis, University of Minnesota, Minneapolis, MN 2001]; however, this method does not handle effectively problems where the volume of the flow domain is known a priori. This work extends the original domain deformation method to a new isochoric domain deformation method to account for the volume conservation. Like in the original domain deformation method, the unknown shape of the flow domain is mapped onto a reference domain by using the equations of an elastic pseudo-solid; the difference with the original method is that this pseudo-solid is considered incompressible. Because of the incompressibility, the pseudo-pressure of the mapping appears as a Lagrange multiplier in the equations, and it is determined only up to an arbitrary uniform datum. By analyzing the coupled fluid flow-mapping problem, we show that, in the finite-element setting, such pressure datum can be specified by replacing one continuity equation in the fluid domain. (C) 2007 Elsevier Inc. All rights reserved. C1 Rice Univ, Dept Chem & Biomol Engn, Inst Comp & Informat Sci, Houston, TX 77005 USA. Rice Univ, Dept Chem, Carbon Nanotechnol Lab, Smalley Inst Nanoscale Sci & Technol, Houston, TX 77005 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Pasquali, M (reprint author), Rice Univ, Dept Chem & Biomol Engn, Inst Comp & Informat Sci, MS 362,6100 Main St, Houston, TX 77005 USA. EM mp@rice.edu RI Pasquali, Matteo/A-2489-2008 OI Pasquali, Matteo/0000-0001-5951-395X NR 18 TC 6 Z9 6 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD SEP 10 PY 2007 VL 226 IS 1 BP 398 EP 413 DI 10.1016/j.jcp.2007.04.028 PG 16 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 217GN UT WOS:000249936500018 ER PT J AU Rieben, RN White, DA Wallin, BK Solberg, JM AF Rieben, R. N. White, D. A. Wallin, B. K. Solberg, J. M. TI An arbitrary Lagrangian-Eulerian discretization of MHD on 3D unstructured grids SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE magnetohydrodynamics; resistive MHD; electromagnetic diffusion; mixed finite element methods; H(Curl) and H(Div) - conforming methods; discrete differential forms; vector finite elements; operator splitting; electromagnetic advection; constrained transport; TVD schemes; algebraic flux correction; unstructured grids ID DISCRETE DIFFERENTIAL FORMS; MAGNETOHYDRODYNAMIC SIMULATIONS; MAGNETIC DIFFUSION; SCHEMES; ALGORITHMS; TRANSPORT; FIELDS; FLOWS; CODE; FLUX AB We present an arbitrary Lagrangian-Eulerian (ALE) discretization of the equations of resistive magnetohydrodynamics (MHD) on unstructured hexahedral grids. The method is formulated using an operator-split approach with three distinct phases: electromagnetic diffusion, Lagrangian motion, and Eulerian advection. The resistive magnetic induction equation is discretized using a compatible mixed finite element method with a second order accurate implicit time differencing scheme which preserves the divergence-free nature of the magnetic field. At each discrete time step, electromagnetic force and heat terms are calculated and coupled to the hydrodynamic equations to compute the Lagrangian motion of the conducting materials. By virtue of the compatible discretization method used, the invariants of Lagrangian MHD motion are preserved in a discrete sense. When the Lagrangian motion of the mesh causes significant distortion, that distortion is corrected with a relaxation of the mesh, followed by a second order monotonic remap of the electromagnetic state variables. The remap is equivalent to Eulerian advection of the magnetic flux density with a fictitious mesh relaxation velocity. The magnetic advection is performed using a novel variant of constrained transport (CT) that is valid for unstructured hexahedral grids with arbitrary mesh velocities. The advection method maintains the divergence-free nature of the magnetic field and is second order accurate in regions where the solution is sufficiently smooth. For regions in which the magnetic field is discontinuous (e.g. MHD shocks) the method is limited using a novel variant of algebraic flux correction (AFC) which is local extremum diminishing (LED) and divergence preserving. Finally, we verify each stage of the discretization via a set of numerical experiments. Published by Elsevier Inc. C1 Lawrence Livermore Natl Lab, Sci Div B, Livermore, CA 94550 USA. Lawrence Livermore Natl Lab, Engn Technol Div, Livermore, CA USA. Lawrence Livermore Natl Lab, Def Technol Engn Div, Livermore, CA USA. RP Rieben, RN (reprint author), Lawrence Livermore Natl Lab, Sci Div B, Livermore, CA 94550 USA. EM rieben1@llnl.gov NR 38 TC 16 Z9 17 U1 1 U2 6 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD SEP 10 PY 2007 VL 226 IS 1 BP 534 EP 570 DI 10.1016/j.jcp.2007.04.031 PG 37 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 217GN UT WOS:000249936500025 ER PT J AU Chang, B AF Chang, Britton TI The incorporation of the semi-implicit linear equations into Newton's method to solve radiation transfer equations SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE radiation transport; nonlinear systems; Newton ID DIFFUSION-SYNTHETIC ACCELERATION; DISCRETE-ORDINATES EQUATIONS AB For large time steps, the nonlinear equations of radiation transfer may not be solved adequately by the semi-implicit linear approximation to yield physical solutions. This deficiency is rectified in three steps: the equations of the semi-implicit linear method are modified, the modified equations are incorporated into Newton's method to solve nonlinear equations, and the transfer equations are solved by the resulting method. The new method also uses the Photon Free Method to search for the solution in a lower dimensional space than the space of the underlying transfer equations. Two algorithms are developed from the new method; they solve the modified semi-implicit linear equations by different approaches. The first is a physics approach; it solves the linear equations approximately by the Grey Transport Approximation. The second is a mathematical approach; it solves the linear equations exactly by the Sherman-Morrison-Woodbury formula of linear algebra. However, both algorithms yield the solution to the nonlinear system derived by the Photon Free Method. Therefore, their solutions are equal to within the specified tolerance of the nonlinear solver. Moreover, both methods can take advantage of the unconditional stability which comes with the implicit differencing of the time derivative. The time step which both methods can take is much larger than the time step in which time discretization error is discernible. We shall relate the mathematical approach to the Photon Free Method. Numerical results for three test problems are presented. (C) 2007 Elsevier Inc. All rights reserved. C1 Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Chang, B (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, POB 808 L-561, Livermore, CA 94551 USA. EM bchang@llnl.gov NR 27 TC 3 Z9 3 U1 1 U2 5 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD SEP 10 PY 2007 VL 226 IS 1 BP 852 EP 878 DI 10.1016/j.jcp.2007.05.038 PG 27 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 217GN UT WOS:000249936500039 ER PT J AU Olson, GL AF Olson, Gordon L. TI Efficient solution of multi-dimensional flux-limited nonequilibrium radiation diffusion coupled to material conduction with second-order time discretization SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID TEMPORAL ACCURACY; EQUATIONS; INTEGRATION; TRANSPORT AB Many algorithms for the second-order time evolution of the coupled radiation diffusion and material conduction equations have been published. Most of them are cumbersome to implement and much slower computationally than their first-order equivalent algorithms. This paper presents a simpler approach that is both computationally efficient and easy to implement. Second-order behavior can be achieved even when the iteration at each time step is incompletely converged. The test problem uses multiple materials and nonlinear heat capacities. Unexpectedly, details in the discretization of the gradient in the flux limiter significantly affect the spatial and temporal convergence of the solution. Published by Elsevier Inc. C1 Los Alamos Natl Lab, Comp & Computat Sci Div CCS2, Madison, WI 53717 USA. RP Olson, GL (reprint author), Los Alamos Natl Lab, Comp & Computat Sci Div CCS2, 5 Foxglove Circle, Madison, WI 53717 USA. EM olson_g@tds.net NR 16 TC 18 Z9 21 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD SEP 10 PY 2007 VL 226 IS 1 BP 1181 EP 1195 DI 10.1016/j.jcp.2007.05.015 PG 15 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 217GN UT WOS:000249936500053 ER PT J AU Berman, GP Gorshkov, VN Tsifrinovich, VI AF Berman, G. P. Gorshkov, V. N. Tsifrinovich, V. I. TI Ground states of Heisenberg spin chains via quantum annealing SO PHYSICS LETTERS A LA English DT Article AB We suggest using the method of quantum annealing for computing the ground state of the Heisenberg spin chains. Our initial Hamiltonian describes a spin system in a highly non-uniform magnetic field. The initial Hamiltonian gradually transforms into the Heisenberg Hamiltonian, which describes the exchange interaction and the Zeeman interaction with the uniform magnetic field. We demonstrate quantum annealing for 2-, 3-, and 9-spin systems. In particular, we consider the alternate (ferro- and antifezomagnetic) exchange integral. By changing the sign of the exchange integrals we switch from the frustrated to the corresponding non-frustrated spin system. We discuss the similarity and difference between the frustrated and non-frustrated spin systems. Published by Elsevier B.V. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87544 USA. Natl Acad Sci Ukraine, Inst Phys, Kiev, Ukraine. Polytech Univ, Dept Phys, Brooklyn, NY 11201 USA. RP Gorshkov, VN (reprint author), Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87544 USA. EM VN-Gorshkov@i.ua RI Gorshkov, Vyacheslav/J-3329-2015 OI Gorshkov, Vyacheslav/0000-0002-7700-5649 NR 2 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD SEP 10 PY 2007 VL 369 IS 1-2 BP 151 EP 156 DI 10.1016/j.physleta.2007.04.105 PG 6 WC Physics, Multidisciplinary SC Physics GA 214XW UT WOS:000249772700024 ER PT J AU Narayanan, RA Thiyagarajan, P Zhu, AJ Ash, J Shofner, ML Schadler, LS Kumar, SK Sternstein, SS AF Narayanan, R. Aravinda Thiyagarajan, P. Zhu, Ai-Jun Ash, J. Shofner, M. L. Schadler, Linda S. Kumar, Sanat K. Sternstein, S. S. TI Nanostructural features in silica-polyvinyl acetate nanocomposites characterized by small-angle scattering SO POLYMER LA English DT Article DE nanocomposites; reinforcement; small-angle scattering ID DIFFUSION-LIMITED AGGREGATION; RECOVERY KINETICS; POLYMERS; DISPERSION; ELASTOMERS AB Sinall-angle scattering (SAS) experiments were carried out on nanocomposites of poly(vinyl acetate) (PVAc) and fumed silica nanoparticles with different surface areas and chemical treatment, in the wave-vector (Q) range: 0.0002-1 angstrom(-1). SAS data on composites with matrices of two different molecular weights indicate that the particle aggregation is independent of the molecular weight of the matrix for a fixed filler concertration and surface treatment. Particle size distributions derived from the SAS data suggest that particle aggregation is reduced when the native surface hydroxyl groups are blocked by various surface treatments, which also reduce the bonding strength to the polymer matrix. The unified exponential/power-law analysis of the SAS data shows three levels of hierarchy in the organization of silica particles. The first level consists of small aggregates of silica particles. At the second level we observe polydispersed aggregates resembling mass-fractal objects that is corroborated by TEM. The polydispersed aggregates further associate to form agglomerates at the third level. The relevance of these findings to the mechanism of nanofiller reinforcement of linear amorphous polymers above T, is discussed. (C) 2007 Elsevier Ltd. All rights reserved. C1 Argonne Natl Lab, Intense Pulsed Neutron Source Div, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. Rensselaer Polytech Inst, Dept Mat Sci & Engn, Troy, NY 12180 USA. RP Thiyagarajan, P (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source Div, 9700 S Cass Ave, Argonne, IL 60439 USA. EM thiyaga@anl.gov; sterns@rpi.edu RI USAXS, APS/D-4198-2013 NR 27 TC 11 Z9 11 U1 2 U2 15 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD SEP 10 PY 2007 VL 48 IS 19 BP 5734 EP 5741 DI 10.1016/j.polymer.2007.07.049 PG 8 WC Polymer Science SC Polymer Science GA 220MO UT WOS:000250161000033 ER PT J AU Aldajah, S Ajayi, OO Fenske, GR Goldblatt, IL AF Aldajah, S. Ajayi, O. O. Fenske, G. R. Goldblatt, I. L. TI Effect of exhaust gas recirculation (EGR) contamination of diesel engine oil on wear SO WEAR LA English DT Article; Proceedings Paper CT 16th International Conference on Wear of Materials CY APR 15-19, 2007 CL Montreal, CANADA DE EGR; soot particles; friction; wear; diesel engine; oil AB Exhaust gas recirculation (EGR) is one of the effective means to reduce the NOx emission from diesel engines. Returning exhaust product to the diesel engine combustion chamber accelerated the degradation of the lubricant engine oil, primarily by increasing the total acid number (TAN) as well as the soot content and, consequently, the viscosity. These oil degradation mechanisms were observed in engine oil exposed to EGR during a standard Cummins M-1 1 diesel engine test. Four-ball wear tests with M-50 balls showed that, although the used oils slightly decrease the friction coefficients, they increased the ball wear by two orders of magnitude when compared to tests with clean oil. Wear occurred primarily by an abrasive mechanism, but in oil with the highest soot loading of 12%, scuffing and soot particle embedment were also observed. Laboratory wear tests showed a linear correlation with the TAN, while the crosshead wear during the engine test was proportional to the soot content. Published by Elsevier B.V. C1 Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. BP Global Lubricants Technol Wayne, Wayne, NJ 07470 USA. United Arab Emirates Univ, Dept Mech Engn, Al Ain, U Arab Emirates. RP Ajayi, OO (reprint author), Argonne Natl Lab, Div Energy Syst, 9700 S Cass Ave, Argonne, IL 60439 USA. EM ajayi@anl.gov OI Aldajah, Saud/0000-0001-6061-1004 NR 14 TC 30 Z9 32 U1 0 U2 12 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD SEP 10 PY 2007 VL 263 SI SI BP 93 EP 98 DI 10.1016/j.wear.2006.12.055 PN 1 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 217LY UT WOS:000249950600012 ER PT J AU Truhan, J Menon, R LeClaire, F Wallin, J Qu, J Blau, P AF Truhan, John Menon, Ravi LeClaire, Frank Wallin, Jack Qu, Jun Blau, Peter TI The friction and wear of various hard-face claddings for deep-hole drilling SO WEAR LA English DT Article; Proceedings Paper CT 16th International Conference on Wear of Materials CY APR 15-19, 2007 CL Montreal, CANADA DE deep-hole drilling; slurry; abrasion; hard-face cladding AB Hard-face claddings are used for banding drill shafts that rotate against well casings while lubricated by drilling mud. This tribosystem should have the lowest friction possible in order to minimize drilling power requirements, and the lowest total system wear to maximize component life. Blocks representing a variety of hard-face claddings were slid against rotating rings of AISI 4140 casing material and lubricated by simulated drilling mud that consisted of a slurry of silica sand, clay, and water. The cladding specimens included currently used alloys and several candidate compositions. There was an excellent correlation between the friction coefficient and the wear, by weight loss, of both the cladding and the casing alloys. There was also a good direct correlation between the wear of the cladding and the wear of the casing. Claddings with finer grain sizes and finer, more uniformly distributed hard carbides had higher hardness and produced lower wear on both the cladding and the casing counter-face. The complex mechanisms involved with three-body wear and friction in interfaces lubricated by slurries present a challenge for further study. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Tennessee, Knoxville, TN 37996 USA. Stoody Co, Bowling Green, KY USA. Oak Ridge Natl Lab, Mat Sci & Technol Div, Oak Ridge, TN USA. RP Truhan, J (reprint author), Univ Tennessee, Knoxville, TN 37996 USA. EM Truhan_John_J@cat.com OI Qu, Jun/0000-0001-9466-3179 NR 6 TC 4 Z9 4 U1 0 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD SEP 10 PY 2007 VL 263 SI SI BP 234 EP 239 DI 10.1016/j.wear.2007.01.046 PN 1 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 217LY UT WOS:000249950600027 ER PT J AU Qu, J Blau, PJ Jolly, BC AF Qu, Jun Blau, Peter J. Jolly, Brian C. TI Tribological properties of stainless steels treated by colossal carbon supersaturation SO WEAR LA English DT Article; Proceedings Paper CT 16th International Conference on Wear of Materials CY APR 15-19, 2007 CL Montreal, CANADA DE stainless steel; colossal supersaturation carburization; wear-resistance; corrosion-resistance ID LOW-TEMPERATURE; CARBURIZATION; DIFFUSION; CARBIDES AB A promising, alternative surface treatment to traditional case carburizing was recently developed. It enables extremely high ('colossal') supersaturation of carbon (up to 12 at.%) in austenitic stainless steel surfaces. This new treatment offers the advantage of hardening the surface while still retaining the corrosion resistance of stainless steels. In this study, the tribological properties of the colossal supersaturation carburized Type 316 stainless steel were investigated and benchmarked against non-treated steel. The carburized surfaces exhibited higher hardness, higher elastic modulus, and higher resistance to acid etching than non-treated surfaces. Hot hardness measurements were conducted and linear relations between the hardness and temperature were observed for both treated and non-treated specimens. The friction and wear characteristics were evaluated at both room and elevated temperatures (200 and 400 degrees C under non-lubricated sliding conditions (pin-on-disk). Additional room-temperature tests were performed in salt water. Improved wear-resistance was observed on the treated surfaces at all test conditions, though less benefit was observed at elevated temperatures or in salt water. (C) 2007 Elsevier B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. RP Qu, J (reprint author), Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. EM qujn@ornl.gov OI Qu, Jun/0000-0001-9466-3179 NR 11 TC 22 Z9 22 U1 3 U2 10 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD SEP 10 PY 2007 VL 263 SI SI BP 719 EP 726 DI 10.1016/j.wear.2006.12.049 PN 1 PG 8 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 217LY UT WOS:000249950600091 ER PT J AU Lorenzo-Martin, C Ajayi, OO Singh, D Routbort, JL AF Lorenzo-Martin, C. Ajayi, O. O. Singh, D. Routbort, J. L. TI Evaluation of scuffing behavior of single-crystal zirconia ceramic materials SO WEAR LA English DT Article DE scuffing; zirconia; plastic deformation; phase transformation; ferroelastic; fracture ID PLASTIC-DEFORMATION AB Scuffing described as sudden catastrophic failure of lubricated sliding surfaces, is usually characterized by a sudden rapid increase in friction, is in severe plastic deformation temperature. and noise. and is an important failure mode on sliding surfaces. In metallic materials, scuffing results of surfaces in contact. This study evaluated the scuffing behavior of two variants of zircoma (ZrO2,) ceramic. Using a block-on-ring contact configuration and unformulated polyalphaolefin (PAO) lubricant, step-load-increase scuffing tests were conducted with single crystals of cubic ZrO2-9.5% Y2O3 and tetragonal ZrO2-3% Y2O3- Phenomenological "scuffing", characterized by a sudden rise in friction coefficient and noise, was observed in the cubic material. For this material, "scuffing" occurred by sudden fracture at the end of test. The tetragonal material underwent no sudden failure (scuffing). This lack of scuffing is attributed to the sequential operation of three plastic deformation mechanisms: ferroelastic domain switching. tetragonal-to-monoclinic phase transformation, and dislocation slip as the frictional stress and energy dissipation pathway. Published by Elsevier B.V. C1 Argonne Natl Lab, Energy Syst Div, Argonne, IL 60439 USA. RP Ajayi, OO (reprint author), Argonne Natl Lab, Energy Syst Div, 9700 S Cass Ave, Argonne, IL 60439 USA. EM ajayi@anl.gov NR 14 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD SEP 10 PY 2007 VL 263 SI SI BP 872 EP 877 DI 10.1016/j.wear.2006.12.054 PN 2 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 214QZ UT WOS:000249754500002 ER PT J AU Schwartz, CJ Bahadur, S Mallapragada, SK AF Schwartz, Christian J. Bahadur, Shyam Mallapragada, Surya K. TI Effect of crosslinking and Pt-Zr quasicrystal fillers on the mechanical properties and wear resistance of UHMWPE for use in artificial joints SO WEAR LA English DT Article DE quasicrystals; UHMWPE; crosslinkmg; dynamic mechanical properties; impact toughness; wear ID MOLECULAR-WEIGHT POLYETHYLENE; COMPOSITES; FRICTION AB The use of artificial joints is common for restoration of comfort and functionality in joints that have been afflicted with cartilage loss due to disease or injury. These implants incorporate an articulating interface of ultra-high molecular weight polyethylene (UHMWPE) sliding against a polished metallic counterface such as 316L stainless steel. While the design of these joints has been refined over several decades, there are still significant limitations to their pain-free lifetime due to osteolysis induced by UHMWPE particulate. Crosslinking has been used recently to increase the wear resistance of the polymer, but there are significant tradeoffs involving reduced elastic modulus and impact toughness. The authors have proposed using Pt-Zr quasicrystals (QC) as fillers in UHMWPE as a method of increasing the wear resistance of the polymer while avoiding significant losses in mechanical properties. UHMWPE samples that had been irradiation crosslinked, filled with 20 wt.% Pt-Zr quasicrystals, or both, were tested in a dynamic mechanical analyzer to determine their viscoelastic properties. Furthermore, Charpy impact tests were performed on these materials. as well as multi-directional sliding wear tests in the dual axis wear simulator (DAWS), a machine designed to simulate in vivo joint wear conditions. It was found that while crosslinking reduced elastic modulus of UHMWPE over 30%, the use of QC fillers led to a slight increase. Additionally, the reduction in impact toughness when using QC fillers was not as great as with crosslinking. Finally, it was found that both QC fillers and crosslinking provided the same significant reduction in wear amounts over untreated UHMWPE. The reduction in wear is explained in terms of the wear mechanisms. This involves inhibition of polymer chain orientation in the case of crosslinking, and shear load shielding effects of quasicrystals in the case of QC-filled polymer. These results suggest that Pt-Zr quasicrystal filler may be a desirable alternative to crosslinking when attempting to increase the wear resistance of UHMWPE for biomedical applications. (C) 2007 Elsevier B.V. All rights reserved. C1 Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. Iowa State Univ, Dept Mech Engn, Ames, IA 50011 USA. Iowa State Univ, Dept Biol & Chem Engn, Ames, IA 50011 USA. US DOE, Ames Lab, Ames, IA 50011 USA. RP Schwartz, CJ (reprint author), Texas A&M Univ, Dept Mech Engn, 3123 TAMU, College Stn, TX 77843 USA. EM cschwartz@tamu.edu RI Mallapragada, Surya/F-9375-2012 NR 22 TC 27 Z9 35 U1 1 U2 15 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD SEP 10 PY 2007 VL 263 SI SI BP 1072 EP 1080 DI 10.1016/j.wear.2006.10.023 PN 2 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 214QZ UT WOS:000249754500029 ER PT J AU Blau, PJ Jolly, BC Qu, J Peter, WH Blue, CA AF Blau, Peter J. Jolly, Brian C. Qu, Jun Peter, William H. Blue, Craig A. TI Tribological investigation of titanium-based materials for brakes SO WEAR LA English DT Article DE disk brakes; sliding friction; titanium alloys; thermal sprayed coatings; titanium composites; friction material ID WEAR MECHANISMS; FRICTION; ALLOYS AB Titanium alloys and their composites have the potential to reduce truck disc brake component weight and improve their resistance to road-salt corrosion. A titanium alloy rotor can weigh approximately 37% less than a conventional cast iron rotor with the same dimensions, while offering Good high-temperature strength and much better resistance to corrosion from road-deicing salts. Friction coefficients and temperature rise data were obtained for two commercial Ti alloys, four experimental Ti-based hard particle composites, and a thermally spray-coated Ti alloy. Several commercially produced lining materials were used as counterfaces. Using a flat block pressed against a rotating disc, tests consisted of repetitive on-and-off drags at sliding speeds from 2 to 15 m/s, using nominal contact pressures of 1.0 or 2.0 MPa. Friction coefficients were affected by the choice of counterface (semi-metallic versus highly metallic lining composition) and by the friction-induced wear track temperature, which at times exceeded 800 degrees C. The wear rates of the Ti metal matrix composites exceeded that of the reference cast iron, but were significantly better that that of two Ti alloys. A thermal conversion parameter was used to compare the efficiency by which various material combinations convert frictional work into temperature rise. Several of the tested material combinations provided friction coefficients within the typical range for brake materials (0.35-0.55) and some showed excellent resistance to fade, a phenomenon in which braking effectiveness decreases as temperature rises. The thermally spray-coated Ti disc exhibited the least wear and merits further attention as a lightweight, corrosion-resistant brake rotor material. (C) 2007 Elsevier B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN USA. RP Blau, PJ (reprint author), POB 2008, Oak Ridge, TN 37831 USA. EM blaupj@ornl.gov OI Qu, Jun/0000-0001-9466-3179 NR 18 TC 24 Z9 25 U1 4 U2 20 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD SEP 10 PY 2007 VL 263 SI SI BP 1202 EP 1211 DI 10.1016/j.wear.2006.12.015 PN 2 PG 10 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 214QZ UT WOS:000249754500044 ER PT J AU Ng, D Kulkarni, M Johnson, J Zinovev, A Yang, D Liang, H AF Ng, D. Kulkarni, M. Johnson, J. Zinovev, A. Yang, D. Liang, H. TI Oxidation and removal mechanisms during chemical-mechanical planarization SO WEAR LA English DT Article DE chemical-mechanical planarization (CMP); passivation; abrasion; friction; wear ID THIN-FILMS; SILICON-NITRIDE; COPPER; ALUMINUM; TRIBOCHEMISTRY; FRICTION; TECHNOLOGY; CORROSION; BEHAVIOR; EROSION AB This paper studies surface properties of metals during chemical-mechanical polishing (CMP). In order to pinpoint the effects of chemistry and mechanical impacts separately, during CMP, we polished Cu and Al surfaces using two distinct slurries of hydrogen peroxide (11202) and alumina nanoparticles. After polishing, detailed characterization of the surface quality and chemical composition were conducted using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and nanoindentation techniques. It was found that nanoparticles were effective in removing surface materials while passivation provides a high quality layer. The application of H2O2 slurries in combination with friction stimulation produced an oxide layer. Depending on the nature of metals, it was found that Cu forms an active and non-equilibrium oxide layer while Al has a stable one. The oxide layer resulted from two competing mechanisms, passivation and abrasion. It was deduced from kinetics that oxidation dominated the initial formation of the surface layer while mechanical sweeping determined the final film thickness. New material-removal mechanisms are proposed. (c) 2007 Elsevier B.V. All rights reserved. C1 Texas A&M Univ, College Stn, TX 77843 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Hysitron Inc, Minneapolis, MN 55344 USA. RP Liang, H (reprint author), Texas A&M Univ, College Stn, TX 77843 USA. EM hliang@tamu.edu RI Johnson, Jacqueline/P-4844-2014 OI Johnson, Jacqueline/0000-0003-0830-9275 NR 43 TC 14 Z9 23 U1 1 U2 13 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD SEP 10 PY 2007 VL 263 SI SI BP 1477 EP 1483 DI 10.1016/j.wear.2006.11.023 PN 2 PG 7 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 214QZ UT WOS:000249754500080 ER PT J AU Ribeiro, R Shan, Z Minor, AM Liang, H AF Ribeiro, R. Shan, Z. Minor, A. M. Liang, H. TI In situ observation of nano-abrasive wear SO WEAR LA English DT Article DE nano-abrasive wear; nano-sliding; in situ observation; transmission electron microscopy; ploughing; voids formation ID INDUCED PHASE-TRANSFORMATIONS; RAMAN MICROSPECTROSCOPY; SILICON; NANOINDENTATION; MICROSCOPY; INDENTATION; NUCLEATION; WEDGE AB We have studied the nano-scale wear behavior using an in situ nanoindentation device in a transmission electron microscope. Nano-scale sliding experiments were conducted under TEM. In order to trigger localized changes, we used a gold-coated diamond indenter to slide against single crystal silicon (100). With the movement of the indenter, cracks along the elastic strain contours in the silicon were observed. Energy analysis was carried over possible mechanisms. It was observed that the onset of abrasive wear was due to cracks formation along the contour. Analysis of the possible mechanisms that lead to the abrasive wear is presented. Observations are presented as initial work into experimentally observing the fundamental mechanisms. (c) 2007 Elsevier B.V. All rights reserved. C1 Texas A&M Univ, College Stn, TX 77843 USA. Lawrence Berkeley Natl Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Liang, H (reprint author), Texas A&M Univ, College Stn, TX 77843 USA. EM hliang@tamu.edu NR 25 TC 19 Z9 20 U1 0 U2 16 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD SEP 10 PY 2007 VL 263 SI SI BP 1556 EP 1559 DI 10.1016/j.wear.2006.10.026 PN 2 PG 4 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 214QZ UT WOS:000249754500092 ER PT J AU Sandel, BR Denton, MH AF Sandel, Bill R. Denton, Michael H. TI Global view of refilling of the plasmasphere SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID MODEL; DEPLETION; DYNAMICS AB We use observations by the IMAGE Extreme Ultraviolet Imager (EUV) to characterize the outflow of He+ from the ionosphere to the plasmasphere under quiet conditions. The view afforded by the IMAGE orbit encompasses the entire plasmasphere in a single exposure, enabling us to examine for the first time the globally-averaged properties of plasmasphere refilling. We focus on a study period that begins with a moderate erosion event, and follow refilling during multiple orbits for a period of 69 hours. The inferred volume refilling rate, averaged over azimuth and time, ranges from similar to 1 He+ cm(-3) h(-1) at L = 3.3 to similar to 7 x 10(-2) He+ cm(-3) h(-1) at L = 6.3 and is generally consistent with earlier, more local measurements. We show that the measured radial abundance profiles match those predicted by the Sheffield University Plasmasphere Ionosphere Model (SUPIM) for 2 <= L <= 4. C1 Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. Univ Lancaster, Dept Commun Syst, Lancaster, England. Los Alamos Natl Lab, ISR 1, Los Alamos, NM USA. RP Sandel, BR (reprint author), Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. OI Denton, Michael/0000-0002-1748-3710 NR 19 TC 20 Z9 20 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 EI 1944-8007 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD SEP 7 PY 2007 VL 34 IS 17 AR L17102 DI 10.1029/2007GL030669 PG 5 WC Geosciences, Multidisciplinary SC Geology GA 209BX UT WOS:000249364300005 ER PT J AU Miller, Y Chaban, GM Zhou, J Asmis, KR Neumark, DM Gerber, RB AF Miller, Yifat Chaban, Galina M. Zhou, Jia Asmis, Knut R. Neumark, Daniel M. Gerber, R. Benny TI Vibrational spectroscopy of (SO(4)(2-))center dot(H(2)O)(n) clusters, n=1-5: Harmonic and anharmonic calculations and experiment SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SELF-CONSISTENT-FIELD; DENSITY-FUNCTIONAL THEORY; AB-INITIO; BIOLOGICAL MOLECULES; GAS-PHASE; EMPIRICAL POTENTIALS; SULFATE DIANION; WAVE-FUNCTIONS; BASIS SETS; ROW ATOMS AB The vibrational spectroscopy of (SO(4)(2-))center dot(H(2)O)(n) is studied by theoretical calculations for n=1-5, and the results are compared with experiments for n=3-5. The calculations use both ab initio MP2 and DFT/B3LYP potential energy surfaces. Both harmonic and anharmonic calculations are reported, the latter with the CC-VSCF method. The main findings are the following: (1) With one exception (H(2)O bending mode), the anharmonicity of the observed transitions, all in the experimental window of 540-1850 cm(-1), is negligible. The computed anharmonic coupling suggests that intramolecular vibrational redistribution does not play any role for the observed linewidths. (2) Comparison with experiment at the harmonic level of computed fundamental frequencies indicates that MP2 is significantly more accurate than DFT/B3LYP for these systems. (3) Strong anharmonic effects are, however, calculated for numerous transitions of these systems, which are outside the present observation window. These include fundamentals as well as combination modes. (4) Combination modes for the n=1 and n=2 clusters are computed. Several relatively strong combination transitions are predicted. These show strong anharmonic effects. (5) An interesting effect of the zero point energy (ZPE) on structure is found for (SO(4)(2-))center dot(H(2)O)(5): The global minimum of the potential energy corresponds to a C(s) structure, but with incorporation of ZPE the lowest energy structure is C(2v), in accordance with experiment. (6) No stable structures were found for (OH(-))center dot(HSO(4)(-))center dot(H(2)O)(n), for n <= 5. (C) 2007 American Institute of Physics. C1 Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. Hebrew Univ Jerusalem, Fritz Haber Res Ctr, IL-91904 Jerusalem, Israel. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Free Univ Berlin, Inst Expt Phys, D-14195 Berlin, Germany. Max Planck Gesell, Fritz Haber Inst, D-14195 Berlin, Germany. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Gerber, RB (reprint author), Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. EM benny@fh.huji.ac.il RI Neumark, Daniel/B-9551-2009; Asmis, Knut/N-5408-2014 OI Neumark, Daniel/0000-0002-3762-9473; Asmis, Knut/0000-0001-6297-5856 NR 44 TC 36 Z9 36 U1 0 U2 18 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD SEP 7 PY 2007 VL 127 IS 9 AR 094305 DI 10.1063/1.2764074 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 208MP UT WOS:000249323700013 PM 17824737 ER PT J AU Tschauner, O Kiefer, B Lee, Y Pravica, M Nicol, M Kim, E AF Tschauner, O. Kiefer, B. Lee, Y. Pravica, M. Nicol, M. Kim, E. TI Structural transition of PETN-I to ferroelastic orthorhombic phase PETN-III at elevated pressures SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PERIODIC HARTREE-FOCK; AUGMENTED-WAVE METHOD; PENTAERYTHRITOL TETRANITRATE; HYDROSTATIC COMPRESSION; MOLECULAR-DYNAMICS; NITRAMINE CRYSTALS; SHOCK INITIATION; ORIENTATION; SENSITIVITY; REFINEMENT AB Using powder x-ray diffraction and first-principles calculations, we provide evidence for a structural transition of PETN-I below 6 GPa to an orthorhombic phase of space group P2(1)2(1)2. The transition can be rationalized as shear-stress induced and ferroelastic, which involves a slight static displacement of the molecules that breaks the fourfold symmetry of PETN-I. Previously reported changes in the optical spectra reflect a lifting of the twofold degeneracy of modes in tetragonal PETN-I. The observed transition is expected to induce soft shear compliances along specific directions in PETN crystallites that may relate to the observed dependence of detonation pressure on crystal orientation. (C) 2007 American Institute of Physics. C1 Univ Nevada, Dept Phys, High Pressure Sci & Engn Ctr, Las Vegas, NV 89154 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Yonsei Univ, Dept Earth Syst Sci, Seoul 120749, South Korea. RP Tschauner, O (reprint author), Univ Nevada, Dept Phys, High Pressure Sci & Engn Ctr, Las Vegas, NV 89154 USA. RI Lee, Yongjae/K-6566-2016 NR 36 TC 11 Z9 11 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD SEP 7 PY 2007 VL 127 IS 9 AR 094502 DI 10.1063/1.2769357 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 208MP UT WOS:000249323700019 PM 17824743 ER PT J AU Yu, HG Muckerman, JT Francisco, JS AF Yu, Hua-Gen Muckerman, James T. Francisco, Joseph S. TI Quantum force molecular dynamics study of the reaction of O atoms with HOCO094302 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POTENTIAL-ENERGY SURFACE; CO REACTANT COMPLEX; HIGH-PRESSURE RANGE; AB-INITIO DYNAMICS; RATE CONSTANTS; TRAJECTORY CALCULATIONS; VIBRATIONAL-EXCITATION; INFRARED-SPECTROSCOPY; HOCO RADICALS; GAS-PHASE AB The reaction of HOCO with O atoms has been studied using a direct ab initio dynamics approach based on the scaling all correlation UCCD/D95(d,p) method. Ab initio calculations point to two possible reaction mechanisms for the O+HOCO -> OH+CO2 reaction. They are a direct hydrogen abstraction and an oxygen addition reaction through a short-lived HOC(O)O intermediate. The dynamics results show that only the addition mechanism is important under the conditions considered here. The lifetime of the HOC(O)O complex is predicted to be 172 +/- 15 fs. This is typical of a direct and fast radical-radical reaction. At room temperature, the calculated thermal rate coefficient is 1.44x10(-11) cm(3) mol(-1) s(-1) and its temperature dependence is rather weak. The two kinds of reactive trajectories are illustrated in detail. (C) 2007 American Institute of Physics. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. RP Yu, HG (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. EM hgy@bnl.gov; muckerma@bnl.gov; francisc@purdue.edu RI Muckerman, James/D-8752-2013; Yu, Hua-Gen/N-7339-2015 NR 52 TC 12 Z9 12 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD SEP 7 PY 2007 VL 127 IS 9 AR 094302 DI 10.1063/1.2770463 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 208MP UT WOS:000249323700010 PM 17824734 ER PT J AU Galinada, WA Guiochon, G AF Galinada, Wilmer A. Guiochon, Georges TI Influence of microwave irradiation on the intraparticle diffusion of an insulin variant in reversed-phase liquid chromatography under linear conditions SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE microwave irradiation; insulin variant; intraparticle diffusion; linear condition; RPLC ID MASS-TRANSFER KINETICS; BOVINE SERUM-ALBUMIN; SURFACE-DIFFUSION; ADSORPTION; BEDS; PARAMETERS; DISPERSION; RADIATION; PROFILES; COLUMNS AB The influence of microwave irradiation on the mass transfer kinetics of an insulin variant in reversed-phase liquid chromatography (RPLC) was investigated. The elution band profiles of insulin were obtained by the pulse-response method, under linear conditions. The RPLC column was placed in a microwave oven and the incremental change in the temperature of the column effluent stream at various microwave energies and mobile phase flow rates were measured. The microwave energy dissipated in the column was set at 15 and 30 W and the mobile phase flow rate was varied from 1.0 to 2.5 mL/min at a mobile phase composition of acetonitrile, water, and trifloroacetic acid (31:69:0.1, v/v/v). The experimental data were analyzed using the conventional method of moment analysis and the lumped pore diffusion model. Regardless of mobile flow rates, the effluent temperatures measured at 15 and 30 W microwave power input were 25 +/- 1 and 30 +/- 1 degrees C, respectively. The effect of microwave irradiation on the mass transfer of the variant insulin was determined by comparing the band profiles obtained under the same experimental conditions, at the same column temperature, with and without irradiation. The calculated intraparticle diffusion coefficient, D-e at 30 W (30 +/- 1 degrees C) microwave irradiation was ca. 20% higher than without irradiation at 30 +/- 1 degrees C. These preliminary results suggest that microwave irradiation may have a significant influence on the intraparticle diffusion of insulin in RPLC. (C) 2007 Elsevier B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. EM guiochon@utk.edu NR 46 TC 8 Z9 11 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD SEP 7 PY 2007 VL 1163 IS 1-2 BP 157 EP 168 DI 10.1016/j.chroma.2007.06.047 PG 12 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 208HQ UT WOS:000249310800016 PM 17631301 ER PT J AU Marchetti, N Cavazzini, A Gritti, F Guiochon, G AF Marchetti, Nicola Cavazzini, Alberto Gritti, Fabrice Guiochon, Georges TI Gradient elution separation and peak capacity of columns packed with porous shell particles SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE bovine serum albumin; gradient elution; myoglobin; peak capacity shell particles; statistics of band overlap ID PERFORMANCE LIQUID-CHROMATOGRAPHY; REVERSED-PHASE SYSTEMS; RETENTION; PRESSURE; DESIGN AB The separation of the tryptic digests of myoglobin and bovine serum albumin were carried out in the gradient elution mode, using water, acetonitrile and TFA as the mobile phase components and columns packed with a new type of shell particles, Halo C-18. These particles give very high efficiencies, characterized with an unusually low eddy diffusion contribution and a small mass transfer contribution. However, because the molecular diffusivities of the peptides in the digest are small, the mobile phase velocity corresponding to the optimum velocity for maximum efficiency is also small, of the order of 0.3 mm/s. The gradient slopes also must be small. Peak capacities of 400 were achieved, with analysis time of the order of an hour. (C) 2007 Elsevier B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Ferrara, Dept Chem, I-44100 Ferrara, Italy. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. EM guiochon@utk.edu RI Marchetti, Nicola/G-4933-2010; Cavazzini, Alberto/B-7051-2015; OI Cavazzini, Alberto/0000-0002-2510-0871; Marchetti, Nicola/0000-0001-5595-570X NR 21 TC 74 Z9 74 U1 2 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD SEP 7 PY 2007 VL 1163 IS 1-2 BP 203 EP 211 DI 10.1016/j.chroma.2007.06.046 PG 9 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 208HQ UT WOS:000249310800020 PM 17632112 ER PT J AU Malecki, M Jedrzejczak, R Stepien, PP Golik, P AF Malecki, Michal Jedrzejczak, Robert Stepien, Piotr P. Golik, Pawel TI In vitro reconstitution and characterization of the yeast mitochondrial degradosome complex unravels tight functional interdependence SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE mitochondria; RNA degradation; mitochondrial degradosome; exoribonuclease; helicase ID MESSENGER-RNA TURNOVER; DEAD-BOX PROTEINS; SACCHAROMYCES-CEREVISIAE; HELICASE ACTIVITY; TRANSLATION INITIATION; GENE-EXPRESSION; RIBONUCLEASE-II; POSTTRANSCRIPTIONAL PROCESSES; ARABIDOPSIS-THALIANA; REACTION-MECHANISM AB The mitochondrial degradosome (mtEXO), the main RNA-degrading complex of yeast mitochondria, is composed of two subunits: an exoribonuclease encoded by the DSS1 gene and an RNA helicase encoded by the SUV3 gene. We expressed both subunits of the yeast mitochondrial degradosome in Escherichia coli, reconstituted the complex in vitro and analyzed the RNase, ATPase and helicase activities of the two subunits interdependence. For every enzymatic activity, we observed significant changes when the relevant protein was present in the complex, compared to the activity measured for the protein alone. The ATPase activity of Suv3p is stimulated by RNA and its background activity in the absence of RNA is reduced greatly when the protein is in the complex with Dss1p. The Suv-3 protein alone does not display RNA-unwinding activity and the 3' to 5' directional helicase activity requiring a free 3' single-stranded substrate becomes apparent only when Suv3p is in complex with Dss1p. The Dssl protein alone does have some basal exoribonuclease activity, which is not ATP-dependent, but in the presence of Suv3p the activity of the entire complex is enhanced greatly and is entirely ATP-dependent, with no residual activity observed in the absence of ATP. Such absolute ATP-dependence is unique among known exoribonuclease complexes. On the basis of these results, we propose a model in which the Suv3p RNA helicase acts as a molecular motor feeding the substrate to the catalytic centre of the RNase subunit. (c) 2007 Elsevier Ltd. All rights reserved. C1 Univ Warsaw, Dept Genet & Biotechnol, PL-02106 Warsaw, Poland. Argonne Natl Lab, MCL Natl Canc Inst, Synchrotron Radiat Res Stn, Argonne, IL 60439 USA. Polish Acad Sci, Inst Biochem & Biophys, PL-02106 Warsaw, Poland. RP Golik, P (reprint author), Univ Warsaw, Dept Genet & Biotechnol, Pawinskiego 5A, PL-02106 Warsaw, Poland. EM pgolik@igib.uw.edu.pl RI Golik, Pawel/D-7788-2011 OI Golik, Pawel/0000-0001-7814-482X FU Intramural NIH HHS NR 74 TC 32 Z9 33 U1 0 U2 1 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 EI 1089-8638 J9 J MOL BIOL JI J. Mol. Biol. PD SEP 7 PY 2007 VL 372 IS 1 BP 23 EP 36 DI 10.1016/j.jmb.2007.06.074 PG 14 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 207TN UT WOS:000249274100004 PM 17658549 ER PT J AU Zhong, Y Macrander, AT Krasnicki, S Chu, YS Maj, J Assoufid, L Qian, J AF Zhong, Y. Macrander, A. T. Krasnicki, S. Chu, Y. S. Maj, J. Assoufid, L. Qian, J. TI Rocking curve FWHM maps of a chemically etched (001) oriented HPHT type Ib diamond crystal plate SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID SYNCHROTRON-RADIATION BEAMS; ADVANCED PHOTON SOURCE; X-RAY; SYNTHETIC DIAMOND; MONOCHROMATOR; RESOLUTION AB Synchrotron radiation and a CCD detector were employed to map the full width at half maximum ( FWHM) of rocking curves for a synthetic ( 0 0 1) oriented type Ib diamond plate. The plate was sawed from a diamond grown in the high- pressure - high- temperature ( HPHT) process. Maps for broadening relative to a reference point on the diamond for the ( 2 2 4) reflection at 12 keV are reported before and after chemical etching. Significant rocking curve narrowing over most of the diamond was found, and we conclude that the diffraction performance of ( 0 0 1) oriented type Ib diamonds can be significantly improved over a large area by chemical etching. Stripes in the map before etching corresponded to grooves formed in the process of sawing the plate out of the as- grown stone. The FWHM map did not correlate with the surface height profile measured after similar to 10 mu m were removed from the surface by etching. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Zhong, Y (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 28 TC 6 Z9 6 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD SEP 7 PY 2007 VL 40 IS 17 BP 5301 EP 5305 DI 10.1088/0022-3727/40/17/043 PG 5 WC Physics, Applied SC Physics GA 200TM UT WOS:000248785700043 ER PT J AU Xu, Y Allen, LJS Perelson, AS AF Xu, Yaji Allen, Linda J. S. Perelson, Alan S. TI Stochastic model of an influenza epidemic with drug resistance SO JOURNAL OF THEORETICAL BIOLOGY LA English DT Article DE continuous-time markov chain; drug resistance; final size; influenza epidemic ID PANDEMIC INFLUENZA; OSELTAMIVIR RESISTANCE; ADAMANTANE RESISTANCE; UNITED-STATES; A VIRUSES; EMERGENCE; STRATEGIES; TUBERCULOSIS; PERSISTENCE; EVOLUTION AB A continuous-time Markov chain (CTMC) model is formulated for an influenza epidemic with drug resistance. This stochastic model is based on an influenza epidemic model, expressed in terms of a system of ordinary differential equations (ODE), developed by Stilianakis, N.I., Perelson, A.S., Hayden, F.G., [1998. Emergence of drug resistance during an influenza epidemic: insights from a mathematical model. J. Inf. Dis. 177, 863-873]. Three different treatments-chemoprophylaxis, treatment after exposure but before symptoms, and treatment after symptoms appear, are considered. The basic reproduction number, 10, is calculated for the deterministic-model under different treatment strategies. It is shown that chemoprophylaxis always reduces the basic reproduction number. In addition, numerical simulations illustrate that the basic reproduction number is generally reduced with realistic treatment rates. Comparisons are made among the different models and the different treatment strategies with respect to the number of infected individuals during an outbreak. The final size distribution is computed for the CTMC model and, in some cases, it is shown to have a bimodal distribution corresponding to two situations: when there is no outbreak and when an outbreak occurs. Given an outbreak occurs, the total number of cases for the CTMC model is in good agreement with the ODE model. The greatest number of drug resistant cases occurs if treatment is delayed or if only symptomatic individuals are treated. (c) 2007 Elsevier Ltd. All rights reserved. C1 Texas Tech Univ, Dept Math & Stat, Lubbock, TX 79409 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Allen, LJS (reprint author), Texas Tech Univ, Dept Math & Stat, Lubbock, TX 79409 USA. EM linda.j.allen@ttu.edu RI Xu, Yaji/M-4985-2015 FU NIAID NIH HHS [R01 AI028433, R01 AI028433-09, R37 AI028433, AI28433] NR 38 TC 16 Z9 17 U1 1 U2 13 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-5193 J9 J THEOR BIOL JI J. Theor. Biol. PD SEP 7 PY 2007 VL 248 IS 1 BP 179 EP 193 DI 10.1016/j.jtbi.2007.05.009 PG 15 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA 210PY UT WOS:000249469300015 PM 17582443 ER PT J AU Campbell, EA Greenwell, R Anthony, JR Wang, S Lim, L Das, K Sofia, HJ Donohue, TJ Darst, SA AF Campbell, Elizabeth A. Greenwell, Roger Anthony, Jennifer R. Wang, Sheng Lim, Lionel Das, Kalyan Sofia, Heidi J. Donohue, Timothy J. Darst, Seth A. TI A conserved structural module regulates transcriptional responses to diverse stress signals in bacteria SO MOLECULAR CELL LA English DT Article ID ANTI-SIGMA FACTOR; SECONDARY STRUCTURE PREDICTION; RHODOBACTER-SPHAEROIDES; CRYSTAL-STRUCTURE; RNA-POLYMERASE; ZINC-BINDING; MACROMOLECULAR STRUCTURES; SELENOMETHIONYL PROTEINS; STREPTOMYCES-COELICOLOR; ANOMALOUS DIFFRACTION AB A transcriptional response to singlet oxygen in Rhodobacter sphaeroides is controlled by the group IV sigma factor sigma(E) and its cognate anti-sigma ChrR. Crystal structures of the sigma(E)/ChrR complex reveal a modular, two-domain architecture for ChrR. The ChrR N-terminal anti-sigma domain (ASID) binds a Zn2+ ion, contacts sigma(E), and is sufficient to inhibit sigma(E)-dependent transcription. The ChrR C-terminal domain adopts a cupin fold, can coordinate an additional Zn2+, and is required for the transcriptional response to singlet oxygen. Structure-based sequence analyses predict that the ASID defines a common structural fold among predicted group IV antias. These ASDs are fused to diverse C-terminal domains that are likely involved in responding to specific environmental signals that control the activity of their cognate sigma factor. C1 Rockefeller Univ, New York, NY 10021 USA. Univ Wisconsin, Dept Bacteriol, Madison, WI 53706 USA. Rutgers State Univ, Ctr Adv Biotechnol & Med, Dept Chem & Chem Biol, Piscataway, NJ 08854 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Darst, SA (reprint author), Rockefeller Univ, 1230 York Ave, New York, NY 10021 USA. EM darst@rockefeller.edu OI Donohue, Timothy/0000-0001-8738-2467 FU NIGMS NIH HHS [GM053759, R01 GM053759, R01 GM075273, R01 GM075273-02] NR 51 TC 81 Z9 83 U1 2 U2 10 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 1097-2765 J9 MOL CELL JI Mol. Cell PD SEP 7 PY 2007 VL 27 IS 5 BP 793 EP 805 DI 10.1016/j.molcel.2007.07.009 PG 13 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 216AK UT WOS:000249849900009 PM 17803943 ER PT J AU VanDemark, AP Kasten, MM Ferris, E Heroux, A Hill, CP Cairns, BR AF VanDemark, Andrew P. Kasten, Margaret M. Ferris, Elliott Heroux, Annie Hill, Christopher P. Cairns, Bradley R. TI Autoregulation of the Rsc4 tandem bromodomain by Gcn5 acetylation SO MOLECULAR CELL LA English DT Article ID CHROMATIN-REMODELING COMPLEX; HISTONE H3; DNA TRANSLOCATION; STRUCTURAL BASIS; BINDING; YEAST; RECOGNITION; NUCLEOSOME; DOMAIN; ACETYLTRANSFERASE AB An important issue for chromatin remodeling complexes is how their bromodomains recognize particular acetylated lysine residues in histones. The Rsc4 subunit of the yeast remodeler RSC contains an essential tandem bromodomain (TBD) that binds acetylated K14 of histone H3 (H3K14ac). We report a series of crystal structures that reveal a compact TBD that binds H3K14ac in the second bromodomain and, remarkably, binds acetylated K25 of Rsc4 itself in the first bromodomain. Endogenous Rsc4 is acetylated only at K25, and Gcn5 is identified as necessary and sufficient for Rsc4 K25 acetylation in vivo and in vitro. Rsc4 K25 acetylation inhibits binding to H3K14ac, and mutation of Rsc4 K25 results in altered growth rates. These data suggest an autoregulatory mechanism in which Gcn5 performs both the activating (H3K14ac) and inhibitory (Rsc4 K25ac) modifications, perhaps to provide temporal regulation. Additional regulatory mechanisms are indicated as H3S10 phosphorylation inhibits Rsc4 binding to H3K14ac peptides. C1 Univ Utah, Sch Med, Dept Biochem, Salt Lake City, UT 84112 USA. Univ Utah, Howard Hughes Med Inst, Salt Lake City, UT 84112 USA. Univ Utah, Dept Oncol Sci, Salt Lake City, UT 84112 USA. Univ Utah, Huntsman Canc Inst, Salt Lake City, UT 84112 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Cairns, BR (reprint author), Univ Utah, Sch Med, Dept Biochem, Salt Lake City, UT 84112 USA. EM chris@biochem.utah.edu; brad.cairns@hci.utah.edu FU Howard Hughes Medical Institute; NCI NIH HHS [CA20414]; NIGMS NIH HHS [GM076242, GM60415, R01 GM060415, R01 GM076242] NR 39 TC 76 Z9 77 U1 0 U2 5 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 1097-2765 J9 MOL CELL JI Mol. Cell PD SEP 7 PY 2007 VL 27 IS 5 BP 817 EP 828 DI 10.1016/j.molcel.2007.08.018 PG 12 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 216AK UT WOS:000249849900011 PM 17803945 ER PT J AU Crooks, GE AF Crooks, Gavin E. TI Measuring thermodynamic length SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIVERGENCE MEASURES; GEOMETRY; DISTANCE; ENTROPY; SYSTEMS; MODEL AB Thermodynamic length is a metric distance between equilibrium thermodynamic states. Among other interesting properties, this metric asymptotically bounds the dissipation induced by a finite time transformation of a thermodynamic system. It is also connected to the Jensen-Shannon divergence, Fisher information, and Rao's entropy differential metric. Therefore, thermodynamic length is of central interest in understanding matter out of equilibrium. In this Letter, we will consider how to define thermodynamic length for a small system described by equilibrium statistical mechanics and how to measure thermodynamic length within a computer simulation. Surprisingly, Bennett's classic acceptance ratio method for measuring free energy differences also measures thermodynamic length. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Crooks, GE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. EM GECrooks@lbl.gov RI Crooks, Gavin/H-7111-2012 NR 26 TC 79 Z9 79 U1 2 U2 16 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 7 PY 2007 VL 99 IS 10 AR 100602 DI 10.1103/PhysRevLett.99.100602 PG 4 WC Physics, Multidisciplinary SC Physics GA 208MT UT WOS:000249324100005 PM 17930381 ER PT J AU Rougemaille, N El Gabaly, F Stumpf, R Schmid, AK Thurmer, K Bartelt, NC de la Figuera, J AF Rougemaille, N. El Gabaly, F. Stumpf, R. Schmid, A. K. Thuermer, K. Bartelt, N. C. de la Figuera, J. TI Labyrinthine island growth during Pd/Ru(0001) heteroepitaxy SO PHYSICAL REVIEW LETTERS LA English DT Article ID 2-DIMENSIONAL ISLANDS; RU(0001); DIFFUSION; SURFACES; ALLOYS; STM AB Using low energy electron microscopy we observe that Pd deposited on Ru only attaches to small sections of the atomic step edges surrounding Pd islands. This causes a novel epitaxial growth mode in which islands advance in a snakelike motion, giving rise to labyrinthine patterns. Based on density functional theory together with scanning tunneling microscopy and low energy electron microscopy we propose that this growth mode is caused by a surface alloy forming around growing islands. This alloy gradually reduces step attachment rates, resulting in an instability that favors adatom attachment at fast advancing step sections. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Sandia Natl Labs, Livermore, CA 94550 USA. CNRS, Inst Neel, F-38042 Grenoble, France. Univ Grenoble 1, F-38042 Grenoble 9, France. Univ Autonoma Madrid, E-28049 Madrid, Spain. CSIC, Inst Quim Fis Rocasolano, E-28006 Madrid, Spain. RP Rougemaille, N (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Bartelt, Norman/G-2927-2012; de la Figuera, Juan/E-7046-2010; Thurmer, Konrad/L-4699-2013 OI de la Figuera, Juan/0000-0002-7014-4777; Thurmer, Konrad/0000-0002-3078-7372 NR 14 TC 11 Z9 11 U1 2 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD SEP 7 PY 2007 VL 99 IS 10 AR 106101 DI 10.1103/PhysRevLett.99.106101 PG 4 WC Physics, Multidisciplinary SC Physics GA 208MT UT WOS:000249324100021 PM 17930397 ER PT J AU Chen, H Bockenfeld, D Rempfer, D Kaminski, MD Rosengart, AJ AF Chen, Haitao Bockenfeld, Danny Rempfer, Dietmar Kaminski, Michael D. Rosengart, Axel J. TI Three-dimensional modeling of a portable medical device for magnetic separation of particles from biological fluids SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID EXTRACORPOREAL BLOOD-CIRCULATION; IN-VITRO; NANOPARTICLES; HEMODIALYSIS AB A portable separator has been developed to quantitatively separate blood-borne magnetic spheres in potentially high-flow regimes for the human detoxification purpose. In the separator design, an array of biocompatible capillary tubing and magnetizable wires is immersed in an external magnetic field that is generated by two permanent magnets. The wires are magnetized and the high magnetic field gradient from the magnetized wires helps to collect blood-borne magnetic nano/micro-spheres from the blood flow. In this study, a 3D numerical model was created and the effect of tubing-wire configurations on the capture efficiency of the system was analyzed using COMSOL Multiphysics 3.3 (R). The results showed that the configuration characterized by bi-directionally alternating wires and tubes was the best design with respect to the four starting configurations. Preliminary in vitro experiments verified the numerical predictions. The results helped us to optimize a prototype portable magnetic separator that is suitable for rapid sequestration of magnetic nano/ microspheres from the human blood stream while accommodating necessary clinical boundary conditions. C1 Univ Chicago, Med Ctr, Dept Neurol, Chicago, IL 60637 USA. IIT, Dept Biomed Engn, Chicago, IL 60616 USA. IIT, Dept Mech Mat & Aerosp Engn, Chicago, IL 60616 USA. Argonne Natl Lab, Div Chem Engn, Argonne, IL 60439 USA. Univ Chicago, Med Ctr, Dept Surg Neurosurg, Chicago, IL 60637 USA. RP Chen, H (reprint author), Univ Chicago, Med Ctr, Dept Neurol, Chicago, IL 60637 USA. EM arosenga@neurology.bsd.uchicago.edu NR 28 TC 11 Z9 11 U1 1 U2 10 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 EI 1361-6560 J9 PHYS MED BIOL JI Phys. Med. Biol. PD SEP 7 PY 2007 VL 52 IS 17 BP 5205 EP 5218 DI 10.1088/0031-9155/52/17/007 PG 14 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 205CE UT WOS:000249089900007 PM 17762081 ER PT J AU Plis, SM George, JS Jun, SC Ranken, DM Volegov, PL Schmidt, DM AF Plis, Sergey M. George, John S. Jun, Sung C. Ranken, Doug M. Volegov, Petr L. Schmidt, David M. TI Probabilistic forward model for electroencephalography source analysis SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID ELECTRICAL-IMPEDANCE TOMOGRAPHY; DIPOLE LOCALIZATION ACCURACY; HUMAN BRAIN; HUMAN SKULL; INVERSE PROBLEM; HEAD MODELS; IN-VIVO; EEG; CONDUCTIVITY; MEG AB Source localization by electroencephalography (EEG) requires an accurate model of head geometry and tissue conductivity. The estimation of source time courses from EEG or from EEG in conjunction with magnetoencephalography (MEG) requires a forward model consistent with true activity for the best outcome. Although MRI provides an excellent description of soft tissue anatomy, a high resolution model of the skull (the dominant resistive component of the head) requires CT, which is not justified for routine physiological studies. Although a number of techniques have been employed to estimate tissue conductivity, no present techniques provide the noninvasive 3D tomographic mapping of conductivity that would be desirable. We introduce a formalism for probabilistic forward modeling that allows the propagation of uncertainties in model parameters into possible errors in source localization. We consider uncertainties in the conductivity profile of the skull, but the approach is general and can be extended to other kinds of uncertainties in the forward model. We and others have previously suggested the possibility of extracting conductivity of the skull from measured electroencephalography data by simultaneously optimizing over dipole parameters and the conductivity values required by the forward model. Using Cramer-Rao bounds, we demonstrate that this approach does not improve localization results nor does it produce reliable conductivity estimates. We conclude that the conductivity of the skull has to be either accurately measured by an independent technique, or that the uncertainties in the conductivity values should be reflected in uncertainty in the source location estimates. C1 Los Alamos Natl Lab, Appl Modern Phys Grp, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Comp Sci, Albuquerque, NM 87131 USA. RP Plis, SM (reprint author), Los Alamos Natl Lab, Appl Modern Phys Grp, MS-D454, Los Alamos, NM 87545 USA. EM pliz@cs.unm.edu OI Plis, Sergey/0000-0003-0040-0365; JUN, SUNG CHAN/0000-0001-5357-4436 FU NIBIB NIH HHS [2 R01 EB000310-05]; NIMH NIH HHS [1 R01 MH076282-01] NR 36 TC 13 Z9 14 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD SEP 7 PY 2007 VL 52 IS 17 BP 5309 EP 5327 DI 10.1088/0031-9155/52/17/014 PG 19 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 205CE UT WOS:000249089900014 PM 17762088 ER PT J AU Smith, CD AF Smith, C. D. TI The release 5.1 annotation of Drosophila melanogaster heterochromatin (vol 316, pg 1586, 2007) SO SCIENCE LA English DT Correction C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley Bioinformat & Ontol Project, Berkeley, CA 94720 USA. RP Smith, CD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley Bioinformat & Ontol Project, Berkeley, CA 94720 USA. NR 1 TC 4 Z9 5 U1 1 U2 3 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD SEP 7 PY 2007 VL 317 IS 5843 BP 1325 EP 1325 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 209GR UT WOS:000249377500019 ER PT J AU Cuomo, CA Gueldener, U Xu, JR Trail, F Turgeon, BG Di Pietro, A Walton, JD Ma, LJ Baker, SE Rep, M Adam, G Antoniw, J Baldwin, T Calvo, S Chang, YL DeCaprio, D Gale, LR Gnerre, S Goswami, RS Hammond-Kosack, K Harris, LJ Hilburn, K Kennell, JC Kroken, S Magnuson, JK Mannhaupt, G Mauceli, E Mewes, HW Mitterbauer, R Muehlbauer, G Munsterkotter, M Nelson, D O'Donnell, K Ouellet, T Qi, WH Quesneville, H Roncero, MIG Seong, KY Tetko, IV Urban, M Waalwijk, C Ward, TJ Yao, JQ Birren, BW Kistler, HC AF Cuomo, Christina A. Gueldener, Ulrich Xu, Jin-Rong Trail, Frances Turgeon, B. Gillian Di Pietro, Antonio Walton, Jonathan D. Ma, Li-Jun Baker, Scott E. Rep, Martijn Adam, Gerhard Antoniw, John Baldwin, Thomas Calvo, Sarah Chang, Yueh-Long DeCaprio, David Gale, Liane R. Gnerre, Sante Goswami, Rubella S. Hammond-Kosack, Kim Harris, Linda J. Hilburn, Karen Kennell, John C. Kroken, Scott Magnuson, Jon K. Mannhaupt, Gertrud Mauceli, Evan Mewes, Hans-Werner Mitterbauer, Rudolf Muehlbauer, Gary Muensterkoetter, Martin Nelson, David O'Donnell, Kerry Ouellet, Therese Qi, Weihong Quesneville, Hadi Roncero, M. Isabel G. Seong, Kye-Yong Tetko, Igor V. Urban, Martin Waalwijk, Cees Ward, Todd J. Yao, Jiqiang Birren, Bruce W. Kistler, H. Corby TI The Fusarium graminearum genome reveals a link between localized polymorphism and pathogen specialization SO SCIENCE LA English DT Article ID NEUROSPORA; DNA AB We sequenced and annotated the genome of the filamentous fungus Fusarium graminearum, a major pathogen of cultivated cereals. Very few repetitive sequences were detected, and the process of repeat-induced point mutation, in which duplicated sequences are subject to extensive mutation, may partially account for the reduced repeat content and apparent low number of paralogous (ancestrally duplicated) genes. A second strain of F. graminearum contained more than 10,000 single-nucleotide polymorphisms, which were frequently located near telomeres and within other discrete chromosomal segments. Many highly polymorphic regions contained sets of genes implicated in plant-fungus interactions and were unusually divergent, with higher rates of recombination. These regions of genome innovation may result from selection due to interactions of F. graminearum with its plant hosts. C1 Univ Minnesota, St Paul, MN 55108 USA. MIT, Broad Inst, Cambridge, MA 02142 USA. Tech Univ Munich, D-8050 Freising Weihenstephan, Germany. GSF, Natl Res Ctr Environm & Hlth, Inst Bioinformat, Neuherberg, Germany. Purdue Univ, W Lafayette, IN 47907 USA. Michigan State Univ, E Lansing, MI 48824 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Cordoba, Cordoba, Spain. Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Amsterdam, NL-1012 WX Amsterdam, Netherlands. Univ Nat Resources & Appl Life Sci, BOKU, Vienna, Austria. Rothamsted Res, Harpenden, Herts, England. Agr & Agri Food Canada, Ottawa, ON, Canada. Univ Ottawa, Ottawa, ON, Canada. USDA ARS, Cereal Dis Lab, St Paul, MN 55108 USA. St Louis Univ, St Louis, MO 63103 USA. Univ Arizona, Tucson, AZ 85721 USA. Univ Tennessee, Memphis, TN 38163 USA. USDA ARS, Natl Ctr Agr Utilizat Res, Peoria, IL 61604 USA. Inst Jacques Monod, F-75251 Paris, France. Plant Res Int, Wageningen, Netherlands. Natl Acad Sci Ukraine, Inst Bioorgan Chem & Photochem, Kiev, Ukraine. RP Kistler, HC (reprint author), Univ Minnesota, St Paul, MN 55108 USA. EM hckist@umn.edu RI Guldener, Ulrich/G-5227-2012; Di Pietro, Antonio/K-9220-2014; Tetko, Igor/B-1540-2010; OI Cuomo, Christina/0000-0002-5778-960X; Guldener, Ulrich/0000-0001-5052-8610; Kistler, Harold/0000-0001-5312-6297; Di Pietro, Antonio/0000-0001-5930-5763; Tetko, Igor/0000-0002-6855-0012; Ma, Li-Jun/0000-0002-2733-3708; Roncero, M. Isabel G./0000-0002-5283-7836; Urban, Martin/0000-0003-2440-4352; Nelson, David/0000-0003-0583-5421; Broz, Karen/0000-0001-7928-7216 FU NHGRI NIH HHS [U54 HG003067] NR 16 TC 383 Z9 622 U1 17 U2 130 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD SEP 7 PY 2007 VL 317 IS 5843 BP 1400 EP 1402 DI 10.1126/science.1143708 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 209GR UT WOS:000249377500049 PM 17823352 ER PT J AU Henson, BF Wilson, KR Robinson, JM Nobel, CA Casson, JL Voss, LF Worsnop, DR AF Henson, Bryan F. Wilson, Kevin R. Robinson, Jeanne M. Nobel, Christopher A. Casson, Joanna L. Voss, Laura F. Worsnop, Douglas R. TI Nucleation of bulk phases in the HCl/H2O system SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID HYDROGEN-CHLORIDE; ICE NANOCRYSTALS; H2O ICE; HCL; IONIZATION; SURFACE; MODEL; ADSORPTION; CONVERSION; SOLVATION AB We report experimental results on the low-temperature uptake of HCl on H2O ice (ice). HCl was deposited on the surface at greater than monolayer amounts at 85 K, and the ice substrate was heated. The temperature dependence of the HCl vapor pressure from this phase was measured from 110 to 150 K, with the nucleation of a bulk hydrate phase observed at 150 K. Measurements were conducted in a closed system by simultaneous application of gas phase mass spectrometry and surface spectroscopy to characterize vapor/solid equilibrium and the nucleation of bulk hydrate phases. Combining the nucleation data reported here with data we reported previously (180 to 200 K) and data from two other laboratories (165 and 170 K), the thermodynamic boundaries for the nucleation of both the metastable bulk solution and bulk hydrate phases subsequent to monolayer adsorption of HCl have been determined. The nucleation of the metastable bulk solution phase occurs promptly at monolayer coverage at the ice/liquid coexistence boundary on the binary bulk phase diagram. The nucleation of the bulk hexahydrate occurs from this metastable solution along a locus of points defining a state of constant solution free energy. This measured free energy is -51.2 +/- 0.9 kJ/mol. Finally, the temperature dependence of the HCl vapor pressure from the low-temperature phase is reported here for the first time and is consistent with that of the metastable solution predicted by this thermodynamic model of uptake, extending the range of validity of this model of adsorption followed by bulk solution and hydrate nucleation to a lower bound in temperature of 110 K. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Henson, BF (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM henson@lanl.gov RI Worsnop, Douglas/D-2817-2009; OI Worsnop, Douglas/0000-0002-8928-8017; Robinson, Jeanne/0000-0002-4251-7169 NR 24 TC 1 Z9 1 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD SEP 6 PY 2007 VL 111 IS 35 BP 8635 EP 8641 DI 10.1021/jp074320h PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 205YH UT WOS:000249150600012 PM 17691759 ER PT J AU Jasper, AW Klippenstein, SJ Harding, LB AF Jasper, Ahren W. Klippenstein, Stephen J. Harding, Lawrence B. TI Secondary kinetics of methanol decomposition: Theoretical rate coefficients for (CH2)-C-3+OH, (CH2)-C-3+(CH2)-C-3, and (CH2)-C-3+CH3 SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID MULTIREFERENCE PERTURBATION-THEORY; TRANSITION-STATE THEORY; QUADRATIC CONFIGURATION-INTERACTION; REFERENCE WAVE-FUNCTIONS; RATE CONSTANTS; BASIS-SETS; TRIPLET METHYLENE; FLASH-PHOTOLYSIS; BRANCHING RATIOS; AB-INITIO/RRKM AB Direct variable reaction coordinate transition state theory (VRC-TST) rate coefficients are reported for the (CH2)-C-3 + OH, (CH2)-C-3 + (CH2)-C-3, and (CH2)-C-3 + CH3 barrierless association reactions. The predicted rate coefficient for the (CH2)-C-3 + OH reaction (similar to 1.2 x 10(-1) cml molecule(-1) s(-1) for 300-2500 K) is 4-5 times larger than previous estimates, indicating that this reaction may be an important sink for OH in many combustion systems. The predicted rate coefficients for the (CH2)-C-3 + CH3 and (CH2)-C-3 + (CH2)-C-3 reactions are found to be in good agreement with the range of available experimental measurements. Product branching in the self-reaction of methylene is discussed, and the C2H2 + 2H and C2H2 + H-2 products are predicted in a ratio of 4:1. The effect of the present set of rate coefficients on modeling the secondary kinetics of methanol decomposition is briefly considered. Finally, the present set of rate coefficients, along with previous VRC-TST determinations of the rate coefficients for the self-reactions of CH3 and OH and for the CH3 + OH reaction, are used to test the geometric mean rule for the CH3, (CH2)-C-3, and OH fragments. The geometric mean rule is found to predict the cross-combination rate coefficients for the (CH2)-C-3 + OH and (CH2)-C-3 + CH3 reactions to better than 20%, with a larger (up to 50%) error for the CH3 + OH reaction. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Jasper, AW (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. EM ajasper@sandia.gov; sjk@anl.gov RI Jasper, Ahren/A-5292-2011; OI Klippenstein, Stephen/0000-0001-6297-9187 NR 64 TC 10 Z9 10 U1 0 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD SEP 6 PY 2007 VL 111 IS 35 BP 8699 EP 8707 DI 10.1021/jp0736950 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 205YH UT WOS:000249150600019 PM 17696414 ER PT J AU Sainsbury, T Ikuno, T Okawa, D Pacile, D Frechet, JMJ Zettl, A AF Sainsbury, Toby Ikuno, Takashi Okawa, David Pacile, Daniela Frechet, Jean M. J. Zettl, Alex TI Self-assembly of gold nanoparticles at the surface of amine- and thiol-functionalized boron nitride nanotubes SO JOURNAL OF PHYSICAL CHEMISTRY C LA English DT Article ID MULTIWALLED CARBON NANOTUBES; IMMOBILIZATION; SOLUBILIZATION; NANOCRYSTALS; SPECTROSCOPY; COMPOSITES; CHEMISTRY; TRANSPORT AB Gold nanoparticles have been self-assembled at the surface of both amine- and thiol-functionalized boron nitride nanotubes (BNNTs) in solution. The chemical functionalization of the surface of the BNNTs was achieved following ammonia plasma irradiation in order to generate amine functional groups at the surface of the BNNTs. The amine-functionalized BNNTs (AF-BNNTs) were then covalently modified by the coupling of short-chain thiol-terminated organic molecules to result in thiol-functionalized BNNTs. The functionalization of the BNNTs was characterized using XPS, FT-IR spectroscopy, and EDS, whereas the nanoparticle-nanotube assemblies were characterized using HR-TEM and EELS. This approach constitutes a basis for the preparation of highly functionalized BNNTs and their utilization as nanoscale templates for assembly and integration with other nanoscale materials. C1 Univ Calif Berkeley, Dept Phys, Div Sci Mat, Lawrence Berkeley Nalt Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Div Mat Sci, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Zettl, A (reprint author), Univ Calif Berkeley, Dept Phys, Div Sci Mat, Lawrence Berkeley Nalt Lab, Berkeley, CA 94720 USA. EM azettl@berkeley.edu RI Ikuno, Takashi/N-8454-2014; Zettl, Alex/O-4925-2016; OI Zettl, Alex/0000-0001-6330-136X; Ikuno, Takashi/0000-0002-5322-9373; Pacile, Daniela/0000-0001-6219-3889; Frechet, Jean /0000-0001-6419-0163 NR 43 TC 106 Z9 108 U1 8 U2 77 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1932-7447 J9 J PHYS CHEM C JI J. Phys. Chem. C PD SEP 6 PY 2007 VL 111 IS 35 BP 12992 EP 12999 DI 10.1021/jp072958n PG 8 WC Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 206FS UT WOS:000249169900019 ER PT J AU Nenoff, TM Ockwig, NW Cygan, RT Alam, TM Leung, K Pless, JD Xu, HW Hartl, MA Daemen, LL AF Nenoff, Tina M. Ockwig, Nathan W. Cygan, Randall T. Alam, Todd M. Leung, Kevin Pless, Jason D. Xu, Hongwu Hartl, Monika A. Daemen, Luke L. TI Role of water in the ion selectivity of niobate-based octahedral molecular sieves SO JOURNAL OF PHYSICAL CHEMISTRY C LA English DT Article ID INELASTIC NEUTRON-SCATTERING; AUGMENTED-WAVE METHOD; DYNAMICS; ZEOLITES; SIMULATIONS; SPECTROSCOPY; SPECTRA; MODEL; FORM AB The role of occluded water in ion exchange selectivity is examined in a class of molecular sieves named Sandia Octahedral Molecular Sieves (SOMS: Na2Nb2-xMxO6-x center dot(OH)(x)-H2O (i.e., M = Ti; 0 < x < 0.4)). SOMS exhibit a high selectivity for divalent cations only when the framework Nb(5+) are substituted by M(4+) atoms. Vibrational dynamics of the water molecules with varying charge balancing cations and M atoms are studied by inelastic neutron scattering (INS) measurements and H-1 MAS NMR and correlated to density functional theory and molecular dynamics data. The experimental INS spectra were compared with those of ice Ih to characterize the changes induced by confinement on the occluded H2O and the resulting hydrogen-bonding network. Data indicates that, with increasing M(4+) content and divalent ion exchange, the trend of occluded water molecules is to change from extended rigid ice-like networks to restored bulk-like arrangements with increased solvation effects on the channel charge-balancing cations. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, LANSCE LC, Los Alamos, NM 87545 USA. RP Nenoff, TM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM tmnenof@sandia.gov RI Lujan Center, LANL/G-4896-2012; Hartl, Monika/F-3094-2014; Hartl, Monika/N-4586-2016; OI Hartl, Monika/0000-0002-6601-7273; Hartl, Monika/0000-0002-6601-7273; Xu, Hongwu/0000-0002-0793-6923 NR 41 TC 10 Z9 10 U1 2 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1932-7447 J9 J PHYS CHEM C JI J. Phys. Chem. C PD SEP 6 PY 2007 VL 111 IS 35 BP 13212 EP 13221 DI 10.1021/jp073969j PG 10 WC Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 206FS UT WOS:000249169900047 ER PT J AU Talapin, DV Black, CT Kagan, CR Shevchenko, EV Afzali, A Murray, CB AF Talapin, Dmitri V. Black, Charles T. Kagan, Cherie R. Shevchenko, Elena V. Afzali, Ali Murray, Christopher B. TI Alignment, electronic properties, doping, and on-chip growth of colloidal PbSe nanowires SO JOURNAL OF PHYSICAL CHEMISTRY C LA English DT Article ID FIELD-EFFECT TRANSISTORS; SEMICONDUCTOR NANOWIRES; BUILDING-BLOCKS; NANOPARTICLES; NETWORKS; DEVICES; LOGIC AB Single-crystalline straight, zigzag, helical, and branched nanowires can be synthesized by oriented attachment of PbSe nanocrystals followed by their fusion in the presence of different surfactants. These colloidal nanowires can be aligned in external electrical fields, facilitating their integration into electronic circuits. We show how the nanowire morphology affects the interaction of nanowires with the electric field. Conducting PbSe nanowires can be assembled from nanocrystal building blocks directly on a chip, growing along the electric field. As-formed PbSe nanowires show a p-type conduction that can be switched to an n-type by charge-transfer doping of the nanowires with hydrazine. In this work, we demonstrate strategies for device integration of solution-phase synthesized semiconductor nanowires and explore their electronic properties. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Mol Foundry, Berkeley, CA 94720 USA. IBM Corp, Div Res, Thomas J Watson Res Ctr, Yorktown Hts, NY 10598 USA. RP Talapin, DV (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Mol Foundry, Berkeley, CA 94720 USA. EM dvtalapin@uchicago.edu NR 28 TC 38 Z9 39 U1 3 U2 33 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1932-7447 J9 J PHYS CHEM C JI J. Phys. Chem. C PD SEP 6 PY 2007 VL 111 IS 35 BP 13244 EP 13249 DI 10.1021/jp074156y PG 6 WC Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 206FS UT WOS:000249169900051 ER PT J AU Zhao, YF Heben, MJ Dillon, AC Simpson, LJ Blackburn, JL Dorn, HC Zhang, SBB AF Zhao, Yufeng Heben, Michael J. Dillon, Anne C. Simpson, Lin J. Blackburn, Jeff L. Dorn, Harry C. Zhang, Shengbai B. TI Nontrivial tuning of the hydrogen-binding energy to fullerenes with endohedral metal dopants SO JOURNAL OF PHYSICAL CHEMISTRY C LA English DT Article ID CARBON CAGES; C60H36; ISOMERS; METALLOFULLERENES; BUCKMINSTERFULLERENE; ER-2-AT-C-82; SPECTROSCOPY; SPECTRA; C60F60; NMR AB We report a first-principle study of the tunable hydrogenation of endohedral metallofullerenes M@C-60 and M,@C-60, where M = Li, Be, Mg, Ca, Al, and Sc. The interaction between the encapsulated metal atoms and the C-60 cage leads to a tuning of the hydrogen binding in a desired manner as the hydrogenation proceeds. At lower H densities, when H atoms are too strongly bound to pure C60, the endohedral dopants weaken the binding. The dopants also enhance the hydrogen-binding energy at higher coverages and enable the degree of hydrogenation to be substantially increased relative to that available with empty-cage C60, Overall, the encapsulated metals increase the capacity and improve the energy efficiency for hydrogen storage. We identify materials capable of storing 6.1 wt % hydrogen and elucidate a subtle interplay between reactivity and structure which will be important for designing the next-generation hydrogen- storage materials. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Virginia Polytech Inst & State Univ, Dept Chem, Blacksburg, VA 24061 USA. RP Zhao, YF (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM yufeng_zhao@nrel.gov RI Blackburn, Jeffrey/D-7344-2012; Krausnick, Jennifer/D-6291-2013; Dorn, Harry/K-6830-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 54 TC 11 Z9 11 U1 0 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1932-7447 J9 J PHYS CHEM C JI J. Phys. Chem. C PD SEP 6 PY 2007 VL 111 IS 35 BP 13275 EP 13279 DI 10.1021/jp073482a PG 5 WC Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 206FS UT WOS:000249169900056 ER PT J AU Rini, M Tobey, R Dean, N Itatani, J Tomioka, Y Tokura, Y Schoenlein, RW Cavalleri, A AF Rini, Matteo Tobey, Ra'anan Dean, Nicky Itatani, Jiro Tomioka, Yasuhide Tokura, Yoshinori Schoenlein, Robert W. Cavalleri, Andrea TI Control of the electronic phase of a manganite by mode-selective vibrational excitation SO NATURE LA English DT Article ID INSULATOR-METAL TRANSITION; PEROVSKITE MANGANITE; PR1-XCAXMNO3; MAGNETORESISTANCE; PR0.7CA0.3MNO3 AB Controlling a phase of matter by coherently manipulating specific vibrational modes has long been an attractive ( yet elusive) goal for ultrafast science. Solids with strongly correlated electrons, in which even subtle crystallographic distortions can result in colossal changes of the electronic and magnetic properties, could be directed between competing phases by such selective vibrational excitation. In this way, the dynamics of the electronic ground state of the system become accessible, and new insight into the underlying physics might be gained. Here we report the ultrafast switching of the electronic phase of a magnetoresistive manganite via direct excitation of a phonon mode at 71meV ( 17THz). A prompt, five-order-of-magnitude drop in resistivity is observed, associated with a non-equilibrium transition from the stable insulating phase to a metastable metallic phase. In contrast with light-induced(1-3) and current-driven(4) phase transitions, the vibrationally driven bandgap collapse observed here is not related to hot-carrier injection and is uniquely attributed to a large-amplitude Mn-O distortion. This corresponds to a perturbation of the perovskite-structure tolerance factor, which in turn controls the electronic bandwidth via inter-site orbital overlap(5,6). Phase control by coherent manipulation of selected metal-oxygen phonons should find extensive application in other complex solids-notably in copper oxide superconductors, in which the role of Cu-O vibrations on the electronic properties is currently controversial. Optical conductivity. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. ERATO, Japan Sci & Technol Agcy, Chiyoda Ku, Tokyo 1020075, Japan. AIST, Correlated Electron Res Ctr, Tsukuba, Ibaraki 3058562, Japan. Univ Tokyo, Dept Appl Phys, Tokyo 1138656, Japan. Rutherford Appleton Lab, Cent Laser Facil, Didcot OX11 0QX, Oxon, England. Diamond Light Source, Didcot OX11 0QX, Oxon, England. RP Rini, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. EM mrini@lbl.gov; a.cavalleri1@physics.ox.ac.uk RI Itatani, Jiro/A-3105-2008; Tokura, Yoshinori/C-7352-2009; Schoenlein, Robert/D-1301-2014; OI Itatani, Jiro/0000-0002-4023-7489; Schoenlein, Robert/0000-0002-6066-7566; Dean, Nicky/0000-0002-4219-8807 NR 21 TC 230 Z9 231 U1 8 U2 99 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD SEP 6 PY 2007 VL 449 IS 7158 BP 72 EP 74 DI 10.1038/nature06119 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 207ED UT WOS:000249233500037 PM 17805291 ER PT J AU Quaglioni, S Navratil, P AF Quaglioni, Sofia Navratil, Petr TI The He-4 total photo-absorption cross section with two- plus three-nucleon interactions from chiral effective field theory SO PHYSICS LETTERS B LA English DT Article ID LORENTZ INTEGRAL TRANSFORM; BENCHMARK CALCULATION; RESPONSE FUNCTIONS; 4-NUCLEON FORCE; NUCLEAR-FORCES; CHARGE RADIUS; LAGRANGIANS; PHOTODISINTEGRATION; NEUTRON AB The total photo-absorption cross section of He-4 is evaluated microscopically using two- (NN) and three-nucleon (NNN) interactions based upon chiral effective field theory (XEFF). The calculation is performed using the Lorentz integral transform method along with the ab initio no-core shell model approach. An important feature of the present study is the consistency of the NN and NNN interactions and also, through the Siegert theorem, of the two- and three-body current operators. This is due to the application of the chi EFT framework. The inclusion of the NNN interaction produces a suppression of the low-energy peak and enhancement of the high-energy tail of the cross section. We compare to calculations obtained using other interactions and to representative experiments. The rather confused experimental situation in the giant resonance region prevents discrimination among different interaction models. (c) 2007 Elsevier B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Quaglioni, S (reprint author), Lawrence Livermore Natl Lab, L-414,POB 808, Livermore, CA 94551 USA. EM quaglioni1@llnl.gov; navratil1@llnl.gov NR 51 TC 47 Z9 47 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD SEP 6 PY 2007 VL 652 IS 5-6 BP 370 EP 375 DI 10.1016/j.physletb.2007.06.082 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 210XJ UT WOS:000249488600026 ER PT J AU Cao, Q Hu, QH Khan, S Wang, ZJ Lin, AJ Du, X Zhu, YG AF Cao, Qing Hu, Qin-Hong Khan, Sardan Wang, Zi-Jian Lin, Ai-Jun Du, Xin Zhu, Yong-Guan TI Wheat phytotoxicity from arsenic and cadmium separately and together in solution culture and in a calcareous soil SO JOURNAL OF HAZARDOUS MATERIALS LA English DT Article DE arsenic; cadmium; phytotoxicity; root elongation; median effective concentration; combined effect; toxic unit; additive index ID TRITICUM-AESTIVUM; JOINT TOXICITY; COPPER; LEAD; PLANT; PHYTOCHELATINS; ECOTOXICITY; TOLERANCE; CHEMISTRY; EXPOSURE AB The toxicity of two toxic elements, arsenic (As) and cadmium (Cd) (individually or in combination) on root elongation of wheat seedlings (Triticium aestivum, L.) were investigated both in hydroponics and in soils freshly spiked with the toxic elements. Median effective concentration (EC50) and non-observed effect concentration (NOEC) were used to investigate the toxic thresholds and potencies of the two elements. The EC50 for As was 0.97 mu M in hydroponics and 196 mg kg(-1) in soil, and 4.32 mu M and 449 mg kg(-1) for Cd, respectively. Toxic unit (TU) and additive index (Al) concepts were introduced to determine the combined outcomes, and different behaviors were obtained: synergism in solution culture (EC50mix = 0.36TU(mix) and AI: 1.76) and antagonism in soil experiments (EC50mix = 1.49TU(mix) and Al: -0.33). Furthermore, the data of soil bioavailable As and Cd cannot explain the discrepancy between the results derived from soil and hydroponics experiments. (C) 2007 Elsevier B.V. All rights reserved. C1 Chinese Acad Sci, Ecoenvironm Sci Res Ctr, Beijing 100085, Peoples R China. Lawrence Livermore Natl Lab, Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Peshawar, Dept Environm Sci, Peshawar 25120, Pakistan. Beijing Univ Chem Technol, Coll Chem Engn, Beijing 100029, Peoples R China. RP Zhu, YG (reprint author), Chinese Acad Sci, Ecoenvironm Sci Res Ctr, Beijing 100085, Peoples R China. EM ygzhu@rcees.ac.cn RI Hu, Qinhong/C-3096-2009; Zhu, Yong-Guan/A-1412-2009; Wang, Zijian/A-1538-2009; kHAN, Sardar/H-7452-2015; Khan, Sardar/C-2883-2009 OI Hu, Qinhong/0000-0002-4782-319X; Zhu, Yong-Guan/0000-0003-3861-8482; Wang, Zijian/0000-0002-9847-9691; Khan, Sardar/0000-0002-7060-1771 NR 37 TC 26 Z9 32 U1 1 U2 43 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3894 J9 J HAZARD MATER JI J. Hazard. Mater. PD SEP 5 PY 2007 VL 148 IS 1-2 BP 377 EP 382 DI 10.1016/j.jhazmat.2007.02.050 PG 6 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 208IH UT WOS:000249312500050 PM 17418485 ER PT J AU Jiang, W Bae, IT Weber, WJ AF Jiang, W. Bae, I-T Weber, W. J. TI Disordering and dopant behaviour in Au+-ion- irradiated AlN SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID GAN; DAMAGE; AMORPHIZATION; IMPLANTATION; CERAMICS; DEFECTS AB Single-crystal AlN films on SiC were irradiated at 145 K with 1.0 MeV Au+ ions in a wide range of ion fluences. The accumulation of disorder on both the Al and N sublattices in AlN has been investigated in situ using conventional Rutherford backscattering spectrometry (RBS) and non-RBS along the < 0001 >-axial channelling direction. The results suggest that a disorder saturation stage is attained following an initial disorder increase at doses less than 10 displacements per atom (dpa). A continuously amorphized layer was not formed in AlN for doses up to 208 dpa. Similar disordering behaviour is observed for the Al and N sublattices. The lattice disorder produced at 145 K is thermally stable at room temperature; further irradiation does not induce disorder recovery. The microstructures in the irradiated AlN exhibit both amorphous and crystalline domains at the stage of disorder saturation. The implanted Au does not show significant redistribution during the ion irradiation or room-temperature annealing. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Jiang, W (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM weilin.jiang@pnl.gov RI Weber, William/A-4177-2008 OI Weber, William/0000-0002-9017-7365 NR 24 TC 10 Z9 10 U1 1 U2 12 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD SEP 5 PY 2007 VL 19 IS 35 AR 356207 DI 10.1088/0953-8984/19/35/356207 PG 10 WC Physics, Condensed Matter SC Physics GA 200SL UT WOS:000248783000011 ER PT J AU Krishnan, RS Mackay, ME Duxbury, PM Hawker, CJ Asokan, S Wong, MS Goyette, R Thiyagarajan, P AF Krishnan, R. S. Mackay, M. E. Duxbury, P. M. Hawker, C. J. Asokan, Suba Wong, Michael S. Goyette, Rick Thiyagarajan, P. TI Improved polymer thin-film wetting behavior through nanoparticle segregation to interfaces SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID MOLECULAR ARCHITECTURE; DEWETTING DYNAMICS; POLYSTYRENE FILMS; LIQUID-FILMS; INSTABILITY; RUPTURE; SURFACE; FORCES; SUPPRESSION; SLIPPAGE AB We report a systematic study of improved wetting behavior for thin polymer films containing nanoparticles, as a function of nanoparticle size and concentration, the energy of the substrate and the dielectric properties of the nanoparticles. An enthalpy matched system consisting of polystyrene nanoparticles in linear polystyrene is used to show that nanoparticles are uniformly distributed in the film after spin coating and drying. However, on annealing the film above its bulk glass transition temperature these nanoparticles segregate strongly to the solid substrate. We find that for a wide range of film thicknesses and nanoparticle sizes, a substrate coverage of nanoparticles of approximately amonolayer is required for dewetting inhibition. Cadmium selenide quantum dots also inhibit dewetting of polystyrene thin films, again when a monolayer is present. Moreover, TEM microscopy images indicate that CdSe quantum dots segregate primarily to the air interface. Theoretical interpretation of these phenomena suggests that gain of linear chain configurational entropy promotes segregation of nanoparticles to the solid substrate, as occurs for polystyrene nanoparticles; however, for CdSe nanoparticles this is offset by surface energy or enthalpic terms which promote segregation of the nanoparticles to the air interface. C1 Michigan State Univ, Dept Chem Engn & Mat Sci, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Univ Calif Santa Barbara, Dept Res Lab, Santa Barbara, CA 93106 USA. Rice Univ, Dept Chem, Houston, TX 77251 USA. Rice Univ, Dept Chem Biomol & Engn, Houston, TX 77251 USA. Argonne Natl Lab, Intense Pulse Neutron Source, Argonne, IL USA. RP Krishnan, RS (reprint author), Michigan State Univ, Dept Chem Engn & Mat Sci, E Lansing, MI 48824 USA. RI Hawker, Craig/G-4971-2011; Wong, Michael/F-9286-2010 OI Hawker, Craig/0000-0001-9951-851X; Wong, Michael/0000-0002-3652-3378 NR 48 TC 41 Z9 41 U1 0 U2 30 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 EI 1361-648X J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD SEP 5 PY 2007 VL 19 IS 35 AR 356003 DI 10.1088/0953-8984/19/35/356003 PG 16 WC Physics, Condensed Matter SC Physics GA 200SL UT WOS:000248783000003 ER PT J AU Krupin, O Rotenberg, E Kevan, SD AF Krupin, Oleg Rotenberg, Eli Kevan, S. D. TI Fermi surface and quantum well states of V(110) films on W(110) SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID SPIN-DENSITY WAVES; POSITRON-ANNIHILATION; ELECTRONIC-STRUCTURE; THIN-FILMS; MAGNETIC NANOSTRUCTURES; MOMENTUM DENSITY; INVERSE LIFETIME; PHASE-TRANSITION; ENERGY-BANDS; VANADIUM AB Using angle-resolved photoemission spectroscopy, we have measured the Fermi surface of V(110) films epitaxially grown on a W(110) substrate. We compare our results for thicker films to existing calculations and measurements for bulk vanadium and find generally very good agreement. For thinner films, we observe and analyse a diverse array of quantum well states that split and distort the Fermi surface segments. We have searched unsuccessfully for a thickness-induced topological transition associated with contact between the zone-centre jungle gym and zone-boundary hole ellipsoid Fermi surface segments. We also find no evidence for ferromagnetic splitting of any bands on this surface. C1 [Rotenberg, Eli] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Kevan, S. D.] Univ Oregon, Dept Phys, Eugene, OR 97403 USA. RP Krupin, O (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Rotenberg, Eli/B-3700-2009; Kevan, Stephen/F-6415-2010 OI Rotenberg, Eli/0000-0002-3979-8844; Kevan, Stephen/0000-0002-4621-9142 NR 62 TC 3 Z9 3 U1 0 U2 14 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD SEP 5 PY 2007 VL 19 IS 35 AR 355005 DI 10.1088/0953-8984/19/35/355005 PG 14 WC Physics, Condensed Matter SC Physics GA 261YV UT WOS:000253116800006 ER PT J AU Wang, Y Zerda, TW AF Wang, Yuejian Zerda, T. W. TI Microstructure evaluations of carbon nanotube/diamond/silicon carbide nanostructured composites by size-strain line-broadening analysis methods SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID HIGH-PRESSURE; SUPERHARD MATERIALS; FOURIER-ANALYSIS; HIGH-TEMPERATURE; NANOTUBES; NANOCOMPOSITES; PROFILE; PERSPECTIVES AB Efforts have been made to manufacture novel composite materials with improved properties by incorporating multi-wall carbon nanotubes (MWNTs) into metal or brittle ceramic. Here we prepared dense MWNT/diamond/silicon carbide (SiC) composites under high-pressure and high-temperature (HPHT) conditions by anchoring MWNTs into a diamond/SiC matrix. The measured mechanical properties indicate that the composites have both superior hardness and enhanced fracture toughness. Moreover, we have undertaken an x-ray diffraction line-broadening analysis to elucidate how the microstructures including domain sizes and micro-strains depend on the externally applied temperature and how the microstructures correlate to the macroproperties of the as-fabricated composites. C1 Texas Christian Univ, Dept Phys & Astron, Ft Worth, TX 76129 USA. RP Wang, Y (reprint author), Los Alamos Natl Lab, LANSCE LC, MS H805, Los Alamos, NM 87545 USA. EM yuejianw@lanl.gov; t.zerda@tcu.edu NR 22 TC 5 Z9 5 U1 1 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD SEP 5 PY 2007 VL 19 IS 35 AR 356205 DI 10.1088/0953-8984/19/35/356205 PG 8 WC Physics, Condensed Matter SC Physics GA 200SL UT WOS:000248783000009 ER PT J AU Yang, HB Wang, Z Ding, H AF Yang, H-B Wang, Z. Ding, H. TI Angle-resolved photoemission spectroscopy study on the Fermi surface topology of Na(x)CoO(2) SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID PHASE-TRANSITIONS; SUPERCONDUCTIVITY; DIFFRACTION; NA0.5COO2 AB We report a systematic study on Na(x)CoO(2) (0.3 <= x <= 0.72) using angle-resolved photoemission spectroscopy (ARPES), with a focus on the Fermi surface topology of the metallic samples. Within this doping range, we observed only one large hexagonal Fermi surface around the Gamma-point, which comes from the a(1g) band. Contrary to most band calculations, our results show that the e(g)' bands never cross the Fermi level to form small Fermi surface pockets near the K-point. The enclosed area of the a1g Fermi surface is found to be consistent with the Luttinger theorem within the doping range in this study. We also found that, at x = 1/3, the Fermi surface coincides with the zone boundary of the root 3 x root 3 commensurate ordering, indicating the importance of charge fluctuations in this material. C1 [Yang, H-B] Brookhaven Natl Lab, Condensed Matter & Mat Sci Dept, Upton, NY 11973 USA. Boston Coll, Dept Phys, Chestnut Hill, MA 02167 USA. RP Yang, HB (reprint author), Boston Coll, Dept Phys, Chestnut Hill, MA 02167 USA. NR 30 TC 11 Z9 11 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD SEP 5 PY 2007 VL 19 IS 35 AR 355004 DI 10.1088/0953-8984/19/35/355004 PG 10 WC Physics, Condensed Matter SC Physics GA 261YV UT WOS:000253116800005 ER PT J AU Malliakas, CD Kanatzidis, MG AF Malliakas, Christos D. Kanatzidis, Mercouri G. TI Charge density waves in the square nets of tellurium of AMRETe(4) (A = K, Na; M = Cu, Ag; RE = La, Ce) SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID RARE-EARTH-ELEMENT; RETE3 RE AB The charge density wave distortions of the square nets of tellurium in AMRE Te-4 (A = K, Na; M = Cu, Ag; RE = La, Ce) and RE Te-3 are influenced by the degree of separation and interaction of the tellurium nets. Each combination of A -M - RE in this family generates a unique CDW pattern. C1 Michigan State Univ, Dept Chem, E Lansing, MI 48824 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Kanatzidis, MG (reprint author), Michigan State Univ, Dept Chem, E Lansing, MI 48824 USA. EM m-kanatzidis@northwestern.edu NR 19 TC 11 Z9 11 U1 4 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD SEP 5 PY 2007 VL 129 IS 35 BP 10675 EP + DI 10.1021/ja073986m PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 206UL UT WOS:000249208300030 PM 17696351 ER PT J AU Nelson-Fitzpatrick, N Ophus, C Luber, E Gervais, L Lee, Z Radmilovic, V Mitlin, D Evoy, S AF Nelson-Fitzpatrick, N. Ophus, C. Luber, E. Gervais, L. Lee, Z. Radmilovic, V. Mitlin, D. Evoy, S. TI Synthesis and characterization of Au-Ta nanocomposites for nanomechanical cantilever devices SO NANOTECHNOLOGY LA English DT Article ID HARDNESS; ALLOYS; SYSTEM; FILMS; GOLD AB A gold-tantalum nanocomposite material synthesized using a co-sputtering technique and designed specifically for nanomechanical systems applications is reported. X-ray diffraction, atomic force microscopy, scanning electron microscopy, nanoindentation and four-point probe contact measurements were performed to characterize the bulk and surface characteristics of the films. The films exhibited an increased reduced modulus and hardness as well as a significant grain size reduction while retaining the face-centered cubic ( FCC) structure of pure gold with a very strong < 111 > texture. In addition, the mechanical characterization of a number of 800 nm wide, 50 nm thick Au-5 at.% Ta cantilevers was performed using optical interferometry. Such devices exhibited resonant frequencies ranging from 371 kHz to 10.9 MHz, with resonant qualities as high as Q = 640. C1 Univ Alberta, Dept Elect & Comp Engn, Edmonton, AB T6G 2M7, Canada. Natl Inst Nanotechnol, Edmonton, AB, Canada. Univ Alberta, Dept Chem & Mat Engn, Edmonton, AB T6G 2M7, Canada. Univ Calif Berkeley, Lawrence Berkeley Lab, NCEM, Berkeley, CA 94720 USA. RP Nelson-Fitzpatrick, N (reprint author), Univ Alberta, Dept Elect & Comp Engn, Edmonton, AB T6G 2M7, Canada. EM evoy@ece.ualberta.ca RI Lee, Zonghoon/G-1474-2011; Ophus, Colin/H-2350-2013; Mitlin , David /M-5328-2016; OI Lee, Zonghoon/0000-0003-3246-4072; Mitlin , David /0000-0002-7556-3575; Evoy, Stephane/0000-0003-4587-3502; Luber, Erik/0000-0003-1623-0102; Ophus, Colin/0000-0003-2348-8558 NR 21 TC 5 Z9 5 U1 1 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0957-4484 J9 NANOTECHNOLOGY JI Nanotechnology PD SEP 5 PY 2007 VL 18 IS 35 AR 355303 DI 10.1088/0957-4484/18/35/355303 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Science & Technology - Other Topics; Materials Science; Physics GA 207VD UT WOS:000249278300003 ER PT J AU Gupta, S Cheng, H Mollah, AKMM Jamison, E Morris, S Chance, MR Khrapunov, S Brenowitz, M AF Gupta, Sayan Cheng, Huiyong Mollah, A. K. M. M. Jamison, Elizabeth Morris, Stephanie Chance, Mark R. Khrapunov, Sergei Brenowitz, Michael TI DNA and protein footprinting analysis of the modulation of DNA binding by the N-terminal domain of the Saccharomyces cerevisiae TATA binding protein SO BIOCHEMISTRY LA English DT Article ID RESOLUTION REFINED STRUCTURE; X-RAY RADIOLYSIS; CRYSTAL-STRUCTURE; MASS-SPECTROMETRY; ESCHERICHIA-COLI; SELF-ASSOCIATION; RNA-POLYMERASE; DIMER DISSOCIATION; SIGMA-SUBUNIT; MINOR-GROOVE AB Recombinant full-length Saccharomyces cerevisiae TATA binding protein (TBP) and its isolated C-terminal conserved core domain (TBPc) were prepared with measured high specific DNA-binding activities. Direct, quantitative comparison of TATA box binding by TBP and TBPc reveals greater affinity by TBPc for either of two high-affinity sequences at several different experimental conditions. TBPc associates more rapidly than TBP to TATA box bearing DNA and dissociates more slowly. The structural origins of the thermodynamic and kinetic effects of the N-terminal domain on DNA binding by TBP were explored in comparative studies of TBPc and TBP by "protein footprinting" with hydroxyl radical (center dot OH) side chain oxidation. Some residues within TBPc and the C-terminal domain of TBP are comparably protected by DNA, consistent with solvent accessibility changes calculated from core domain crystal structures. In contrast, the reactivity of some residues located on the top surface and the DNA-binding saddle of the C-terminal domain differs between TBP and TBPc in both the presence and absence of bound DNA; these results are not predicted from the crystal structures. A strikingly different pattern of side chain oxidation is observed for TBP when a nonionic detergent is present. Taken together, these results are consistent with the N-terminal domain actively modulating TATA box binding by TBP and nonionic detergent modulating the interdomain interaction. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Albert Einstein Coll Med, Dept Biochem, Bronx, NY 10461 USA. Yeshiva Univ, Dept Biol, New York, NY 10033 USA. Case Western Reserve Univ, Ctr Prote, Cleveland, OH 44106 USA. Brookhaven Natl Lab, Ctr Synchrotron Biosci, Upton, NY 11973 USA. RP Khrapunov, S (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. EM khraps@aecom.yu.edu; brenowit@aecom.yu.edu NR 69 TC 15 Z9 15 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD SEP 4 PY 2007 VL 46 IS 35 BP 9886 EP 9898 DI 10.1021/bi7003608 PG 13 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 204CN UT WOS:000249021100003 PM 17683121 ER PT J AU McAllister, MJ Li, JL Adamson, DH Schniepp, HC Abdala, AA Liu, J Herrera-Alonso, M Milius, DL Car, R Prud'homme, RK Aksay, IA AF McAllister, Michael J. Li, Je-Luen Adamson, Douglas H. Schniepp, Hannes C. Abdala, Ahmed A. Liu, Jun Herrera-Alonso, Margarita Milius, David L. Car, Roberto Prud'homme, Robert K. Aksay, Ilhan A. TI Single sheet functionalized graphene by oxidation and thermal expansion of graphite SO CHEMISTRY OF MATERIALS LA English DT Article ID EXFOLIATED GRAPHITE; INTERCALATION POLYMERIZATION; CARBON NANOTUBES; NANOCOMPOSITES; SURFACE; OXIDE; DECOMPOSITION; ADSORPTION; COMPOSITE; GAS AB A detailed analysis of the thermal expansion mechanism of graphite oxide to produce functionalized graphene sheets is provided. Exfoliation takes place when the decomposition rate of the epoxy and hydroxyl sites of graphite oxide exceeds the diffusion rate of the evolved gases, thus yielding pressures that exceed the van der Waals forces holding the graphene sheets together. A comparison of the Arrhenius dependence of the reaction rate against the calculated diffusion coefficient based on Knudsen diffusion suggests a critical temperature of 550 degrees C which must be exceeded for exfoliation to occur. As a result of their wrinkled nature, the functionalized and defective graphene sheets do not collapse back to graphite oxide but are highly agglomerated. After dispersion by ultrasonication in appropriate solvents, statistical analysis by atomic force microscopy shows that 80% of the observed flakes are single sheets. C1 Princeton Univ, Dept Chem Engn, Princeton, NJ 08544 USA. Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Princeton Univ, Princeton Inst Sci & Technol Mat, Princeton, NJ 08544 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Aksay, IA (reprint author), Princeton Univ, Dept Chem Engn, Princeton, NJ 08544 USA. EM iaksay@princeton.edu RI Schniepp, Hannes/B-8368-2008; Aksay, Ilhan/B-9281-2008; Herrera-Alonso, Margarita/A-1558-2011; Abdala, Ahmed/A-5474-2009; Adamson, Douglas/C-8721-2009 OI Schniepp, Hannes/0000-0003-4645-9469; Abdala, Ahmed/0000-0002-7398-9118; NR 49 TC 1862 Z9 1912 U1 157 U2 1219 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD SEP 4 PY 2007 VL 19 IS 18 BP 4396 EP 4404 DI 10.1021/cm0630800 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 204CP UT WOS:000249021300007 ER PT J AU Batra, D Hay, DNT Firestone, MA AF Batra, Dolly Hay, Daniel N. T. Firestone, Millicent A. TI Formation of a biomimetic, liquid-crystalline hydrogel by self-assembly and polymerization of an ionic liquid SO CHEMISTRY OF MATERIALS LA English DT Article ID SOLUBILITY PARAMETERS; POLY(IONIC LIQUID)S; CONDUCTIVE FILMS; WATER; GELS; BEHAVIOR; ABSORPTION; ACID); SOFT AB Preparation and polymerization of a methylimidazolium-based ionic liquid (IL) that incorporates an acryloyl moiety at the terminus of a C-8 alkyl chain is described. The IL monomer weakly self-assembles upon addition of water and oligomerizes on mild heating. Initiator-free polymerization (as evidenced by FT-IR spectroscopy) can be achieved by UV irradiation, forming an elastic, self-supporting hydrogel. Small-angle X-ray scattering (SAXS) studies on the unsupported polymer demonstrate that the hydrogel adopts an ordered lamellar structure. The polymer can absorb large quantities of water, swelling to nearly 200 times its original volume and, in the process, becoming a highly disordered lamellar structure. Swelling studies conducted using a range of organic solvents demonstrate that the polymer can also be swollen (albeit to a lesser extent) by polar, hydrogen-bonding solvents such as ethanol. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA. RP Firestone, MA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM firestone@anl.gov NR 44 TC 59 Z9 60 U1 6 U2 60 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD SEP 4 PY 2007 VL 19 IS 18 BP 4423 EP 4431 DI 10.1021/cm062992z PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 204CP UT WOS:000249021300010 ER PT J AU Read, EL Engel, GS Calhoun, TR Mancal, T Ahn, TK Blankenship, RE Fleming, GR AF Read, Elizabeth L. Engel, Gregory S. Calhoun, Tessa R. Mancal, Tomas Ahn, Tae Kyu Blankenship, Robert E. Fleming, Graham R. TI Cross-peak-specific two-dimensional electronic spectroscopy SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE 2D spectroscopy; Fenna-Matthews-Olson; ultrafast spectroscopy ID LIGHT-HARVESTING COMPLEX; FEMTOSECOND SPECTROSCOPY; IR-SPECTROSCOPY; BACTERIOCHLOROPHYLL; PROTEIN; ECHOES AB Intermolecular electronic coupling dictates the optical properties of molecular aggregate systems. Of particular interest are photosynthetic pigment-protein complexes that absorb sunlight then efficiently direct energy toward the photosynthetic reaction center. Two-dimensional (2D) ultrafast spectroscopy has been used widely in the infrared (IR) and increasingly in the visible to probe excitonic couplings and observe dynamics, but the off-diagonal spectral signatures of coupling are often obscured by broad diagonal peaks, especially in the visible regime. Rotating the polarizations of the laser pulses exciting the sample can highlight certain spectral features, and the use of polarized pulse sequences to elucidate cross-peaks in 2D spectra has been demonstrated in the IR for vibrational transitions. Here we develop 2D electronic spectroscopy using cross-peak-specific pulse polarization conditions in an investigation of the Fenna-Matthews-Olson light harvesting complex from green photosynthetic bacteria. Our measurements successfully highlight off-diagonal features of the 2D spectra and, in combination with an analysis based on the signs of features arising from particular energy level pathways and theoretical simulation, we characterize the dominant response pathways responsible for the spectral features. Cross-peak-specific 2D electronic spectroscopy provides insight into the interchromophore couplings, as well as into the energetic pathways giving rise to the signal. With femtosecond resolution, we also observe dynamical processes that depend on these couplings and interactions with the protein environment. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Washington Univ, Dept Biol, St Louis, MO 63130 USA. Washington Univ, Dept Chem, St Louis, MO 63130 USA. RP Fleming, GR (reprint author), Univ Calif Berkeley, Dept Chem, 221 Hildebrand Hall, Berkeley, CA 94720 USA. EM grfleming@lbl.gov RI Engel, Gregory/C-1108-2012; Ahn, Tae/A-5838-2013; Mancal, Tomas/B-9688-2014 OI Engel, Gregory/0000-0002-6740-5243; Mancal, Tomas/0000-0003-1736-3054 NR 24 TC 89 Z9 89 U1 2 U2 31 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD SEP 4 PY 2007 VL 104 IS 36 BP 14203 EP 14208 DI 10.1073/pnas.0701201104 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 208QF UT WOS:000249333600007 PM 17548830 ER PT J AU Pelton, M Smith, G Scherer, NF Marcus, RA AF Pelton, Matthew Smith, Glenna Scherer, Norbert F. Marcus, Rudolph A. TI Evidence for a diffusion-controlled mechanism for fluorescence blinking of colloidal quantum dots SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE fluorescence intermittency; power spectrum; nanocrystals ID CADMIUM SELENIDE NANOCRYSTALS; SEMICONDUCTOR NANOCRYSTALS; INTERMITTENCY; NOISE; STATISTICS; EMISSION AB Fluorescence blinking in nanocrystal quantum dots is known to exhibit power-law dynamics, and several different mechanisms have been proposed to explain this behavior. We have extended the measurement of quantum-dot blinking by characterizing fluctuations in the fluorescence of single dots over time scales from microseconds to seconds. The power spectral density of these fluctuations indicates a change in the power-law statistics that occurs at a time scale of several milliseconds, providing an important constraint on possible mechanisms for the blinking. In particular, the observations are consistent with the predictions of models wherein blinking is controlled by diffusion of the energies of electron or hole trap states. C1 CALTECH, Arthur Amos Noyes Lab Chem Phys, Pasadena, CA 91125 USA. Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA. Univ Chicago, Dept Chem, Chicago, IL 60637 USA. Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. RP Marcus, RA (reprint author), CALTECH, Arthur Amos Noyes Lab Chem Phys, MC 127-72, Pasadena, CA 91125 USA. EM ram@caltech.edu RI Pelton, Matthew/H-7482-2013 OI Pelton, Matthew/0000-0002-6370-8765 FU NIGMS NIH HHS [R01GM67961, R01 GM067961] NR 41 TC 103 Z9 104 U1 2 U2 35 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD SEP 4 PY 2007 VL 104 IS 36 BP 14249 EP 14254 DI 10.1073/pnas.0706164104 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 208QF UT WOS:000249333600015 PM 17720807 ER PT J AU Paddock, ML Wiley, SE Axelrod, HL Cohen, AE Roy, M Abresch, EC Capraro, D Murphy, AN Nechushtai, R Dixon, JE Jennings, PA AF Paddock, Mark L. Wiley, Sandra E. Axelrod, Herbert L. Cohen, Aina E. Roy, Melinda Abresch, Edward C. Capraro, Dominique Murphy, Anne N. Nechushtai, Rachel Dixon, Jack E. Jennings, Patricia A. TI MitoNEET is a uniquely folded 2Fe-2S outer mitochondrial membrane protein stabilized by pioglitazone SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE diabetes; FeS cluster; iron homeostasis; thiazolidinedione; oxidative stress ID INSULIN SENSITIZERS; DIFFRACTION DATA; IRON; BIOGENESIS; MODEL; CRYSTALLOGRAPHY; EUKARYOTES; REFINEMENT; MECHANISMS; CRYSTALS AB Iron-sulfur (Fe-S) proteins are key players in vital processes involving energy homeostasis and metabolism from the simplest to most complex organisms. We report a 1.5 angstrom x-ray crystal structure of the first identified outer mitochondrial membrane Fe-S protein, mitoNEET. Two protomers intertwine to form a unique climeric structure that constitutes a new fold to not only the approximate to 650 reported Fe-S protein structures but also to all known proteins. We name this motif the NEET fold. The protomers form a two-domain structure: a beta-cap domain and a cluster-binding domain that coordinates two acid-labile 2Fe-2S clusters. Binding of pioglitazone, an insulin-sensitizing thiazolidinedione used in the treatment of type 2 diabetes, stabilizes the protein against 2Fe-2S cluster release. The biophysical properties of mitoNEET suggest that it may participate in a redox-sensitive signaling and/or in Fe-S cluster transfer. C1 Univ Calif San Diego, Dept Chem & Biochem, La Jolla, CA 92093 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif San Diego, Dept Pharmacol, La Jolla, CA 92093 USA. Univ Calif San Diego, Dept Cellular & Mol Med, La Jolla, CA 92093 USA. Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. Hebrew Univ Jerusalem, Wolfson Ctr Appl Struct Biol, Dept Plant & Environm Sci, IL-91904 Givat Ram, Israel. RP Jennings, PA (reprint author), Univ Calif San Diego, Dept Chem & Biochem, 9500 Gilman Dr, La Jolla, CA 92093 USA. EM pajennin@ucsd.edu OI Murphy, Anne N/0000-0002-5222-9902 FU NIDDK NIH HHS [DK54441, P01 DK054441]; NIGMS NIH HHS [GM 41637, GM54038, R01 GM041637, R01 GM054038, R29 GM054038]; PHS HHS [18024, 18849] NR 37 TC 117 Z9 120 U1 0 U2 8 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD SEP 4 PY 2007 VL 104 IS 36 BP 14342 EP 14347 DI 10.1073/pnas.0707189104 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 208QF UT WOS:000249333600031 PM 17766440 ER PT J AU Spoerke, ED Voigt, JA AF Spoerke, Erik D. Voigt, James A. TI Influence of engineered peptides on the formation and properties of cadmium sulfide nanocrystals SO ADVANCED FUNCTIONAL MATERIALS LA English DT Article ID COLLOIDAL SEMICONDUCTORS; CDS PARTICLES; REDOX POTENTIALS; CAPPING LIGANDS; SIZE; NANOPARTICLES; PHOTOCHEMISTRY; CRYSTALLITES; NANOCLUSTERS; CHEMISTRY AB Cadmium sulfide (CdS) nanocrystals continue to generate scientific and technological interest, owing to their valuable optical, electronic, and chemical properties. Aqueous nanocrystal syntheses rely on functional capping agents to control nanocrystal form and function. We present a series of linear and dendritic engineered peptides, rich in cysteines and aspartic acids, as CdS capping agents. The chemical composition and peptide geometry were found to significantly influence CdS nanocrystal size, optical properties, and aggregation behavior. C1 Dept Elect & Nanostruct Mat, Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Spoerke, ED (reprint author), Dept Elect & Nanostruct Mat, Sandia Natl Labs, PO Box 5800,MS 1411, Albuquerque, NM 87185 USA. EM edspoer@sandia.gov NR 28 TC 23 Z9 23 U1 1 U2 16 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA POSTFACH 101161, 69451 WEINHEIM, GERMANY SN 1616-301X EI 1616-3028 J9 ADV FUNCT MATER JI Adv. Funct. Mater. PD SEP 3 PY 2007 VL 17 IS 13 BP 2031 EP 2037 DI 10.1002/adfm.200600163 PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 212ZY UT WOS:000249636900004 ER PT J AU Xiong, G Shao, R Droubay, TC Joly, AG Beck, KM Chambers, SA Hess, WP AF Xiong, Gang Shao, Rui Droubay, Timothy C. Joly, Alan G. Beck, Kenneth M. Chambers, Scott A. Hess, Wayne P. TI Photoemission electron microscopy of TiO2 anatase films embedded with rutile nanocrystals SO ADVANCED FUNCTIONAL MATERIALS LA English DT Article ID SURFACE; DIFFUSION; GROWTH; TRANSFORMATION; STOICHIOMETRY AB Photoemission electron microscopy (PEEM) excited by X-ray and UV sources is used to investigate epitaxial anatase thin films with embedded rutile nanocrystals, a model system for the study of heterocatalysis on mixed-phase TiO2. Both excitation sources show distinct contrast between the two TiO2 phases; however, the contrast is reversed. Rutile nanocrystals appear darker than the anatase film in X-ray PEEM images but brighter in UV-PEEM images. We observe that topography-induced contrast is dominant in X-ray PEEM imaging, whereas work function and density-of-state-based contrast, dominates in UV-PEEM. This assertion is confirmed by UPS and conducting AFM data that shows the rutile work function to be 0.2 eV lower and a greater occupied valence band density-of-states in rutile (100) than in anatase (001). Since the boundaries between rutile nanocrystals and the anatase film are clearly resolved, these results indicate that PEEM studies of excited state dynamics and heterocatalysis are possible at chemically intriguing mixed-phase TiO2 interfaces and grain boundaries. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Xiong, G (reprint author), Pacific NW Natl Lab, PO Box 999, Richland, WA 99352 USA. EM xiong.g@gmail.com; wayne.hess@pnl.gov RI Droubay, Tim/D-5395-2016 OI Droubay, Tim/0000-0002-8821-0322 NR 34 TC 73 Z9 73 U1 12 U2 74 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 1616-301X J9 ADV FUNCT MATER JI Adv. Funct. Mater. PD SEP 3 PY 2007 VL 17 IS 13 BP 2133 EP 2138 DI 10.1002/adfm.200700146 PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 212ZY UT WOS:000249636900017 ER PT J AU Wang, XS Wang, H Frankowski, DJ Lam, PG Welch, PM Winnik, MA Hartmann, J Manners, I Spontak, RJ AF Wang, Xiaosong Wang, Hai Frankowski, David J. Lam, Peter G. Welch, Paul M. Winnik, Mitchell A. Hartmann, Juergen Manners, Ian Spontak, Richard J. TI Growth and crystallization of metal-containing block copolymer nanotubes in a selective solvent SO ADVANCED MATERIALS LA English DT Article ID DIBLOCK COPOLYMERS; BICONTINUOUS MORPHOLOGIES; POLYMER CRYSTALLIZATION; DILUTE-SOLUTION; SOLID-STATE; MICELLES; CORE; POLY(FERROCENYLDIMETHYLSILANE-B-DIMETHYLSILOXANE); METHACRYLATE); SEGREGATION AB Highly asymmetric metal-containing block copolymers are capable of forming nanotubes in solutions containing a nonpolar solvent. In this study, the time-dependent formation of these nanotubes is investigated and reveals how the aggregate nanostructures develop (see figure for an example at an early stage). These nanotubes are semicrystalline (see the diffraction pattern in the inset), suggesting that crystallization is at least partially responsible for the unique morphology formed by these block copolymers. C1 Univ Toronto, Dept Chem, Toronto, ON M5S 3H6, Canada. Univ Bristol, Dept Chem, Bristol BS8 1TS, Avon, England. N Carolina State Univ, Dept Chem & Biomol Engn, Raleigh, NC 27695 USA. N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Max Planck Inst Colloids & Interfaces, Dept Colloid Chem, D-14424 Potsdam, Germany. RP Winnik, MA (reprint author), Univ Toronto, Dept Chem, Toronto, ON M5S 3H6, Canada. EM mwinnik@chem.utoronto.ca; ian.manners@bristol.ac.uk; rich_spontak@ncsu.edu RI Wang, Xiaosong/N-8121-2013; Wang, Hai/J-3186-2014; Wang, Hai/M-3820-2016; OI Wang, Hai/0000-0001-9243-3935; Wang, Hai/0000-0001-9243-3935; Welch, Paul/0000-0001-5614-2065 NR 50 TC 28 Z9 28 U1 3 U2 39 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA POSTFACH 101161, 69451 WEINHEIM, GERMANY SN 0935-9648 EI 1521-4095 J9 ADV MATER JI Adv. Mater. PD SEP 3 PY 2007 VL 19 IS 17 BP 2279 EP + DI 10.1002/adma.200602230 PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 211GS UT WOS:000249512900016 ER PT J AU Bartel, TP Kisielowski, C Specht, P Shubina, TV Jmerik, VN Ivanov, SV AF Bartel, T. P. Kisielowski, C. Specht, P. Shubina, T. V. Jmerik, V. N. Ivanov, S. V. TI High resolution transmission electron microscopy of InN SO APPLIED PHYSICS LETTERS LA English DT Article ID ENERGY-LOSS SPECTROSCOPY; FUNDAMENTAL-BAND GAP; INDIUM; ABSORPTION AB Hexagonal InN layers were grown by molecular beam epitaxy and studied by high resolution electron microscopy and by photoluminescence spectroscopy. Inclusions of a few nanometers in diameter were found, which are among the smallest reported. Image simulation, beam sensitivity, and photoluminescence of the samples corroborate that these inclusions are indeed metallic indium. This letter provides evidence that nanoscopic metallic indium inclusions can be present in InN crystals and have a strong influence on its optical properties. (c) 2007 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. RP Bartel, TP (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM tpbartel@lbl.gov RI Bartel, Til/C-1098-2008; Shubina, Tatiana/C-1132-2014; Ivanov, Sergey/C-1177-2014; Jmerik, Valentin/E-3194-2014 NR 16 TC 16 Z9 16 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 3 PY 2007 VL 91 IS 10 AR 101908 DI 10.1063/1.2779843 PG 3 WC Physics, Applied SC Physics GA 208MH UT WOS:000249322900019 ER PT J AU Chai, G Heinrich, H Chow, L Schenkel, T AF Chai, G. Heinrich, H. Chow, L. Schenkel, T. TI Electron transport through single carbon nanotubes SO APPLIED PHYSICS LETTERS LA English DT Article ID BEAMS AB The authors report on the transport of energetic electrons through single, well aligned multiwall carbon nanotubes (CNTs). Embedding of CNTs in a protective carbon fiber coating enables the application of focused ion beam based sample preparation techniques for the nondestructive isolation and alignment of individual tubes. Aligned tubes with lengths of 0.7-3 mu m allow transport of 300 keV electrons in a transmission electron microscope through their hollow cores at zero degree incident angles and for a misalignment of up to 1 degrees. C1 Apollo Technol Inc, Longwood, FL 32750 USA. Univ Cent Florida, Dept Phys, Adv Mat Proc & Anal Ctr, Orlando, FL 32816 USA. EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Chow, L (reprint author), Apollo Technol Inc, 976 Florida Cent Pkwy,Suite 112, Longwood, FL 32750 USA. EM chow@ucf.edu RI Chow, Lee/A-8106-2009 OI Chow, Lee/0000-0001-7729-6848 NR 13 TC 26 Z9 26 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 3 PY 2007 VL 91 IS 10 AR 103101 DI 10.1063/1.2778551 PG 3 WC Physics, Applied SC Physics GA 208MH UT WOS:000249322900054 ER PT J AU Lin, PH Khare, R Weeks, BL Gee, RH AF Lin, Po-Han Khare, Rajesh Weeks, Brandon L. Gee, Richard H. TI Molecular modeling of diffusion on a crystalline pentaerythritol tetranitrate surface SO APPLIED PHYSICS LETTERS LA English DT Article ID PATH AB Surface diffusion on a pentaerythritol tetranitrate (PETN) crystal was investigated by treating the surface diffusion as an activated process in the formalism of transition state theory. In particular, surface diffusion processes on the (110) and (101) facets, as well as diffusion between these facets, were considered. The authors were able to obtain the potential energy barriers required for PETN surface diffusion. Their results show that the (110) surface is more thermally active than the (101) surface and PETN molecules mainly diffuse from the (110) to (101) facet. These results are in good agreement with experimental observations and previous simulations. (C) 2007 American Institute of Physics. C1 Texas Tech Univ, Dept Chem Engn, Lubbock, TX 79409 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lin, PH (reprint author), Texas Tech Univ, Dept Chem Engn, POB 43121, Lubbock, TX 79409 USA. EM rajesh.khare@ttu.edu; brandon.weeks@ttu.edu RI Lin, Po-Han/B-5893-2008; Khare, Rajesh/J-2079-2014; Weeks, Brandon/P-6331-2014; OI Khare, Rajesh/0000-0002-8859-766X; Weeks, Brandon/0000-0003-2552-4129; LIN, PO-HAN/0000-0002-3522-6240 NR 13 TC 6 Z9 7 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 3 PY 2007 VL 91 IS 10 AR 104107 DI 10.1063/1.2783206 PG 3 WC Physics, Applied SC Physics GA 208MH UT WOS:000249322900096 ER PT J AU Michaelson, S Ternyak, O Hoffman, A Williams, OA Gruen, DM AF Michaelson, Sh. Ternyak, O. Hoffman, A. Williams, O. A. Gruen, D. M. TI Hydrogen bonding at grain surfaces and boundaries of nanodiamond films detected by high resolution electron energy loss spectroscopy SO APPLIED PHYSICS LETTERS LA English DT Article ID AMORPHOUS-CARBON FILMS; DIAMOND-LIKE-CARBON; THERMAL-STABILITY; A-C; RELAXATION; EFFUSION; STRESS AB Hydrogenated nanodiamond films consisting of 300 and 10-30 nm grain sizes were examined by high resolution electron energy loss spectroscopy. C-H stretching modes were identified at 350, 360, and 375 meV. The mode at 375 meV was enhanced in the case of 10-30 nm grain size and it is stable up to in situ annealing to >>800 degrees C. Complete hydrogen desorption occurs upon annealing to 1000 degrees C. Exposure of the nanodiamond film to atomic hydrogen results in a strong quenching of the 375 meV C-H mode, most likely due to preferential etching of (sp(2))-carbon-hydrogen at the surface and grain boundaries of the films. C1 Technion Israel Inst Technol, Schulich Fac Chem, IL-32000 Haifa, Israel. Hasselt Univ, Inst Mat Res, B-3590 Diepenbeek, Belgium. IMEC, Div IMOMEC, B-3590 Diepenbeek, Belgium. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Hoffman, A (reprint author), Technion Israel Inst Technol, Schulich Fac Chem, IL-32000 Haifa, Israel. EM choffman@tx.technion.ac.il RI Williams, Oliver/B-2776-2009; OI Williams, Oliver/0000-0002-7210-3004 NR 22 TC 33 Z9 33 U1 1 U2 13 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 3 PY 2007 VL 91 IS 10 AR 103104 DI 10.1063/1.2779848 PG 3 WC Physics, Applied SC Physics GA 208MH UT WOS:000249322900057 ER PT J AU Niemeyer, AC Campbell, IH So, F Crone, BK AF Niemeyer, A. C. Campbell, I. H. So, F. Crone, B. K. TI High quantum efficiency polymer photoconductors using interdigitated electrodes SO APPLIED PHYSICS LETTERS LA English DT Article ID FIELD-ASSISTED DISSOCIATION; CHARGE-TRANSFER STATES; SOLAR-CELLS; RECOMBINATION; ABSORPTION; FILMS; SPECTROSCOPY; IONS AB In this letter the authors investigate photoconductivity in interdigitated lateral photoconductors with aluminum contacts, and a poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene]/ {6}-1-(3-(methoxycarbonyl)propyl)-{5}-1-phenyl-[6,6]-C61 blend as the active layer. They demonstrate quantum efficiencies over 70% in 5 mu m devices. The quantum efficiency spectra follow the absorbance spectra and are not corrected for incomplete absorption of the films. The quantum efficiency is a monotonically increasing function of applied field. The field dependence can be explained with a modified Onsager model for charge dissociation. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. RP Niemeyer, AC (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM bcrone@lanl.gov NR 23 TC 9 Z9 9 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 3 PY 2007 VL 91 IS 10 AR 103504 DI 10.1063/1.2779102 PG 3 WC Physics, Applied SC Physics GA 208MH UT WOS:000249322900075 ER PT J AU Velisavljevic, N Chesnut, GN AF Velisavljevic, Nenad Chesnut, Gary N. TI Direct hcp -> bcc structural phase transition observed in titanium alloy at high pressure SO APPLIED PHYSICS LETTERS LA English DT Article ID CRYSTAL-STRUCTURES; METAL; ZIRCONIUM AB Structural stability of Ti alloy, stabilized as a mixture of bcc (beta) and hcp (alpha) phases, was investigated up to 71 GPa. Over this pressure, beta phase remains stable, while for alpha phase, a decrease in c/a ratio from 1.601 at ambient pressure to 1.568 at 36 GPa is observed, followed by an increase to 1.613 at 44 GPa. A steady value is then observed up to 67 GPa. Above 58 GPa, the authors also observe that alpha phase peak intensity is decreasing. At 67 GPa, the authors only observe beta phase peaks, which indicates that alpha ->beta structural phase transition is complete. (c) 2007 American Institute of Physics. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Velisavljevic, N (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. EM nenad@lanl.gov NR 17 TC 7 Z9 7 U1 1 U2 14 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 3 PY 2007 VL 91 IS 10 AR 101906 DI 10.1063/1.2780078 PG 3 WC Physics, Applied SC Physics GA 208MH UT WOS:000249322900017 ER PT J AU Zepeda-Ruiz, LA Sadigh, B Biener, J Hodge, AM Hamza, AV AF Zepeda-Ruiz, Luis A. Sadigh, Babak Biener, Juergen Hodge, Andrea M. Hamza, Alex V. TI Mechanical response of freestanding Au nanopillars under compression SO APPLIED PHYSICS LETTERS LA English DT Article ID GOLD NANOWIRES; NANOCRYSTALLINE COPPER; ATOMISTIC SIMULATION; PLASTIC-DEFORMATION; METAL NANOWIRES; STRENGTH; SCALE AB We employ molecular dynamics simulations of defect-free nanopillars with realistic cylindrical geometries to obtain an atomic-level picture of their deformation behavior under compression. We find that dislocations are nucleated in the two outermost surface layers. Furthermore, plastic yield depends crucially on the particular arrangement of steps and facets at the surface of the nanopillars. We show that different facet orientations can differ dramatically in their response to external stresses. Freestanding nanopillars exhibit a highly nonuniform distribution of stresses along their height. This causes an elastic deformation that leads to a barrel-like shape attained by the nanopillars under compression. The stress concentration at the center of the pillars due to barreling causes dislocations to preferentially nucleate in this region. (c) 2007 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Chem Mat & Life Sci Directorate, Livermore, CA 94550 USA. RP Zepeda-Ruiz, LA (reprint author), Lawrence Livermore Natl Lab, Chem Mat & Life Sci Directorate, Livermore, CA 94550 USA. EM zepedaruiz1@llnl.gov NR 26 TC 26 Z9 26 U1 1 U2 16 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD SEP 3 PY 2007 VL 91 IS 10 AR 101907 DI 10.1063/1.2778761 PG 3 WC Physics, Applied SC Physics GA 208MH UT WOS:000249322900018 ER PT J AU Schelter, EJ Yang, P Scott, BL Thompson, JD Martin, RL Hay, PJ Morris, DE Kiplinger, JL AF Schelter, Eric J. Yang, Ping Scott, Brian L. Thompson, J. D. Martin, Richard L. Hay, P. Jeffrey Morris, David E. Kiplinger, Jaqueline L. TI Systematic studies of early actinide complexes: Uranium(IV) fluoroketimides SO INORGANIC CHEMISTRY LA English DT Article ID IMPROVED ELECTROCHEMISTRY; BIS(KETIMIDO) COMPLEXES; MAGNETIC-SUSCEPTIBILITY; SUPPORTING ELECTROLYTE; EXCITED-STATES; THORIUM; TETRAHALIDES; SPECTROSCOPY; TRANSITIONS; DYNAMICS AB The reaction of (C5Me5)(2)U(CH3)(2) with 2 equiv of NC-Ar-F gives the fluorinated uranium(IV) bis(ketimide) complexes (C5Me5)(2)U[-NC(CH3)(Ar-F)](2) [where Ar-F = 2-F-C6H4 (4), 3-F-C6H4 (5), 4-F-C6H4 (6), 2,6-F-2-C6H3 (7), 3,5-F-2-C6H3 (8), 2,4,6-F-3-C6H2 (9), 3,4,5-F-3-C6H2 (10), and C6F5 (11)]. These have been characterized by single-crystal X-ray diffraction, H-1 and F-19 NMR, cyclic voltammetry, UV-visible-near-IR absorption spectroscopy, and variable-temperature magnetic susceptibility. Density functional theory (DFT) results are reported for complexes 6 and 11 for comparison with experimental data. The most significant structural perturbation imparted by the F substitution in these complexes is a rotation of the fluorinated aryl (Ar-F) group out of the plane defined by the NC(C-Me)(C-ipso) fragment in complexes 7, 9, and 11 when the Ar-F group possesses two o-fluorine atoms. Excellent agreement is obtained between the DFT-calculated and experimental crystal structures for 11, which displays the distortion, as well as for 6, which does not. In 7, 9, and 11, the out-of-plane rotation results in large angles (phi = 53.7-89.4 degrees) between the planes formed by ketimide atoms NC(C-Me)(C-ipso) and the ketimide aryl groups. Complexes 6 and 10 do not contain o-fluorine atoms and display interplanar angles in the range of phi = 7-26.8 degrees. Complex 4 with a single o-fluorine substituent has intermediate values of phi = 20.4 and 49.5 degrees. The distortions in 7, 9, and 11 result from an unfavorable steric interaction between one of the two o-fluorine atoms and the methyl group [-NC(CH3)] on the ketimide ligand. All complexes exhibit U-V/U-IV and U-IV/U-III redox couples, although the distortion in 7, 9, and 11 appears to be a factor in rendering the U-IV/U-III couple irreversible. The potential separation between these couples remains constant at 2.15 +/- 0.03 V. The electronic spectra are dominated by unusually intense f-f transitions in the near-IR that retain nearly identical band energies but vary in intensity as a function of the fluorinated ketimide ligand, and visible and near-UV bands assigned to metal (5f)-to-ligand (pi*) charge-transfer and interconfiguration (5f(2) -> 5f(1)6d(1)) transitions, respectively. Variable-temperature magnetic susceptibility data for these complexes indicate a temperature-independent paramagnetism (TIP) below similar to 50 K that results from admixing of low-lying crystal-field excited states derived from the symmetry-split H-3(4) 5f(2) manifold into the ground state. The magnitude of the TIP is smaller for the complexes possessing two o-fluorine atoms (7, 9, and 11), indicating that the energy separation between ground and TIP-admixed excited states is larger as a consequence of the greater basicity of these ligands. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hay, PJ (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM pjhay@lanl.gov; demorris@lanl.gov; kiplinger@lanl.gov RI Schelter, Eric/E-2962-2013; Morris, David/A-8577-2012; Kiplinger, Jaqueline/B-9158-2011; Scott, Brian/D-8995-2017; Yang, Ping/E-5355-2011 OI Kiplinger, Jaqueline/0000-0003-0512-7062; Scott, Brian/0000-0003-0468-5396; Yang, Ping/0000-0003-4726-2860; NR 32 TC 58 Z9 58 U1 2 U2 26 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD SEP 3 PY 2007 VL 46 IS 18 BP 7477 EP 7488 DI 10.1021/ic700455b PG 12 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 203OS UT WOS:000248984500037 PM 17691767 ER PT J AU Dolling, G Wegener, M Soukoulis, CM Linden, S AF Dolling, G. Wegener, M. Soukoulis, C. M. Linden, S. TI Design-related losses of double-fishnet negative-index photonic metamaterials SO OPTICS EXPRESS LA English DT Article ID REFRACTIVE-INDEX; WAVELENGTHS AB The literature regarding the influence of the hole shape on the performance, especially on the losses, of negative-index metamaterials on the basis of the so-called double-fishnet structure is unclear. We investigate this aspect in a systematic theoretical study showing that the figure of merit can differ by as much as a factor of 2.5 between rectangular and circular holes, respectively. (c) 2007 Optical Society of America. C1 Univ Karlsruhe, Inst Angew Phys, D-76128 Karlsruhe, Germany. Univ Karlsruhe, DFG Ctr Funct Nanostruct CFN, D-76128 Karlsruhe, Germany. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. FORTH, Inst Elect Struct & Laser, Iraklion, Crete, Greece. Technol Univ Crete, Dept Mat Sci & Technol, Iraklion, Crete, Greece. Forschungszentrum Karlsruhe, Inst Nanotechnol, D-76021 Karlsruhe, Germany. RP Dolling, G (reprint author), Univ Karlsruhe, Inst Angew Phys, Wolfgang Gaede Str 1, D-76128 Karlsruhe, Germany. EM Gunnar.Dolling@physik.uni-karlsruhe.de RI Soukoulis, Costas/A-5295-2008; Wegener, Martin/S-5456-2016 NR 12 TC 53 Z9 55 U1 0 U2 7 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD SEP 3 PY 2007 VL 15 IS 18 BP 11536 EP 11541 DI 10.1364/OE.15.011536 PG 6 WC Optics SC Optics GA 208SP UT WOS:000249339800051 PM 19547511 ER PT J AU Trewyn, BG Slowing, II Giri, S Chen, HT Lin, VSY AF Trewyn, Brian G. Slowing, Igor I. Giri, Supratim Chen, Hung-Ting Lin, Victor S. -Y. TI Synthesis and functionalization of a mesoporous silica nanoparticle based on the sol-gel process and applications in controlled release SO ACCOUNTS OF CHEMICAL RESEARCH LA English DT Review ID RESPONSIVE CONTROLLED-RELEASE; MOLECULAR-SIEVES; DELIVERY-SYSTEM; ORGANIC FUNCTIONALIZATION; NEUROTRANSMITTERS; MORPHOLOGY; CELLS AB Mesoporous silica nanoparticles (MSNs) are introduced as chemically and thermally stable nanomaterials with well-defined and controllable morphology and porosity. It is shown that these particles possess external and internal surfaces that can be selectively functionalized with multiple organic and inorganic groups. On the basis of these characteristics, the biocompatibility of silica, and their efficient uptake by mammalian cells, MSNs are proposed as the basis of nanodevices for the controlled release of drugs and genes into living cells. C1 Iowa State Univ Sci & Technol, Dept Chem, US DOE Ames Lab, Ames, IA 50011 USA. RP Lin, VSY (reprint author), Iowa State Univ Sci & Technol, Dept Chem, US DOE Ames Lab, Ames, IA 50011 USA. EM vsylin@iastate.edu OI Slowing, Igor/0000-0002-9319-8639 NR 27 TC 562 Z9 573 U1 62 U2 548 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0001-4842 J9 ACCOUNTS CHEM RES JI Accounts Chem. Res. PD SEP PY 2007 VL 40 IS 9 BP 846 EP 853 DI 10.1021/ar600032u PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA 212PY UT WOS:000249610500015 PM 17645305 ER PT J AU Foppiano, S Marshall, SJ Marshall, GW Saiz, E Tomsia, AP AF Foppiano, Silvia Marshall, Sally J. Marshall, Grayson W. Saiz, Eduardo Tomsia, Antoni P. TI Bioactive glass coatings affect the behavior of osteoblast-like cells SO ACTA BIOMATERIALIA LA English DT Article DE cell adhesion; cell proliferation; cell differentiation; cytocompatibility ID IONIC PRODUCTS; DISSOLUTION; EXPRESSION; TITANIUM; TRANSFORMATION; PROLIFERATION; PHOSPHATE; IMPLANTS; TI6AL4V; GROWTH AB Functionally graded coatings (FGCs) of bioactive glass on titanium alloy (Ti6Al4V) were fabricated by the enameling technique. These innovative coatings may be an alternative to plasma-sprayed, hydroxyapatite-coated implants. Previously we determined that a preconditioning treatment in simulated body fluid (SBF) helped to stabilize FGCs [Foppiano S et al. Acta Biomater 2006-2(2):13342]. The primary goal of this work was to assess the in vitro cytocompatibility of preconditioned FGCs with MC3T3-E1.4 mouse pre-osteoblastic cells. We evaluated cell adhesion, proliferation and mineralization on FGCs in comparison to uncoated Ti6Al4V and tissue culture polystyrene (TCPS). No difference in cell adhesion was identified, whereas proliferation was significantly different on all materials, being highest on FGCs followed by TCPS and Ti6Al4V. Qualitative and quantitative mineralization assays indicated that mineralization occurred on all materials. The amount of inorganic phosphate released by the mineralizing layers was significantly different, being highest on TCPS, followed by FGC and uncoated Ti6Al4V. The secondary objective of this work was to assess the ability of the FGCs to affect gene expression, indirectly, by means of their dissolution products, which was assessed by real-time reverse-transcription polymerase chain reaction. The FGC dissolution products induced a 2-fold increase in the expression of Runx-2, and a 20%,) decrease in the expression of collagen type I with respect to TCPS extract. These genes are regulators of osteoblast differentiation and mineralization, respectively. The findings of this study indicate that preconditioned FGCs are cytocompatible and suggest that future work may allow composition changes to induce preferred gene expression. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. C1 Univ Calif San Francisco, Div Biomat & Bioengn, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Orthopaed Surg, San Francisco, CA 94110 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Marshall, SJ (reprint author), Univ Calif San Francisco, Div Biomat & Bioengn, 707 Parnassus Ave, San Francisco, CA 94143 USA. EM smarshall@chanoff.ucsf.edu FU NIDCR NIH HHS [R01 DE011289, R01 DE011289-11, R01DE11289] NR 26 TC 48 Z9 48 U1 1 U2 8 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1742-7061 J9 ACTA BIOMATER JI Acta Biomater. PD SEP PY 2007 VL 3 IS 5 BP 765 EP 771 DI 10.1016/j.actbio.2007.02.011 PG 7 WC Engineering, Biomedical; Materials Science, Biomaterials SC Engineering; Materials Science GA 212VQ UT WOS:000249625300016 PM 17466608 ER PT J AU Corbett, MC Latimer, MJ Poulos, TL Sevrioukova, IF Hodgson, KO Hedman, B AF Corbett, Mary C. Latimer, Matthew J. Poulos, Thomas L. Sevrioukova, Irina F. Hodgson, Keith O. Hedman, Britt TI Photoreduction of the active site of the metalloprotein putidaredoxin by synchrotron radiation SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID ELECTRON-SPIN-RESONANCE; X-RAY-IRRADIATION; PROTEIN CRYSTALS; MACROMOLECULAR CRYSTALS; CRYOGENIC TEMPERATURES; ANGSTROM RESOLUTION; PSEUDOMONAS-PUTIDA; STRUCTURAL-CHANGES; CATALYTIC PATHWAY; 2FE-2S FERREDOXIN AB X-ray damage to protein crystals is often assessed on the basis of the degradation of diffraction intensity, yet this measure is not sensitive to the rapid changes that occur at photosensitive groups such as the active sites of metalloproteins. Here, X-ray absorption spectroscopy is used to study the X-ray dose-dependent photoreduction of crystals of the [Fe2S2]-containing metalloprotein putidaredoxin. A dramatic decrease in the rate of photoreduction is observed in crystals cryocooled with liquid helium at 40 K compared with those cooled with liquid nitrogen at 110 K. Whereas structural changes consistent with cluster reduction occur in the active site of the crystal measured at 110 K, no such changes occur in the crystal measured at 40 K, even after an eightfold increase in dose. When the structural results from extended X-ray absorption fine-structure measurements are compared with those obtained by crystallography on this and similar proteins, it is apparent that X-ray-induced photoreduction has had an impact on the crystallographic data and subsequent structure solutions. These results strongly indicate the importance of using liquid-helium-based cooling for metalloprotein crystallography in order to avoid the subtle yet important changes that can take place at the metalloprotein active sites when liquid-nitrogen-based cooling is used. The study also illustrates the need for direct measurement of the redox states of the metals, through X-ray absorption spectroscopy, simultaneously with the crystallographic measurements. C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, SLAC, Menlo Pk, CA 94025 USA. Univ Calif Irvine, Dept Biol Mol, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Biochem, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Physiol & Biophys, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. RP Hodgson, KO (reprint author), Stanford Univ, Dept Chem, Stanford, CA 94305 USA. EM hodgson@ssrl.slac.stanford.edu; hedman@ssrl.slac.stanford.edu FU NCRR NIH HHS [P41 RR-001209, RR-001209]; NIGMS NIH HHS [GM-33688, GM-67367] NR 64 TC 50 Z9 50 U1 1 U2 13 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD SEP PY 2007 VL 63 BP 951 EP 960 DI 10.1107/S0907444907035160 PN 9 PG 10 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 206ES UT WOS:000249167300003 PM 17704563 ER PT J AU Smith, CA Caccamo, M Kantardjieff, KA Vakulenko, S AF Smith, Clyde A. Caccamo, Marisa Kantardjieff, Katherine A. Vakulenko, Sergei TI Structure of GES-1 at atomic resolution: insights into the evolution of carbapenamase activity in the class A extended-spectrum beta-lactamases SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID PSEUDOMONAS-AERUGINOSA; CRYSTAL-STRUCTURE; CARBAPENEMASE ACTIVITY; KLEBSIELLA-PNEUMONIAE; PROTEIN CRYSTALS; DIFFRACTION DATA; REFINEMENT; SPECIFICITY; ENZYME; INTERMEDIATE AB The structure of the class A extended-spectrum beta-lactamase GES-1 from Klebsiella pneumoniae has been determined to 1.1 angstrom resolution. GES-1 has the characteristic active-site disulfide bond of the carbapenemase family of beta-lactamases and has a structure that is very similar to those of other known carbapenemases, including NMC-A, SME-1 and KPC-2. Most residues implicated in the catalytic mechanism of this class of enzyme are present in the GES-1 active site, including Ser70, which forms a covalent bond with the carbonyl C atom of the beta-lactam ring of the substrate during the formation of an acyl-enzyme intermediate, Glu166, which is implicated as both the acylation and deacylation base, and Lys73, which is also implicated as the acylation base. A water molecule crucial to catalysis is observed in an identical location as in other class A beta-lactamases, interacting with the side chains of Ser70 and Glu166. One important residue, Asn170, also normally a ligand for the hydrolytic water, is missing from the GES-1 active site. This residue is a glycine in GES-1 and the enzyme is unable to hydrolyze imipenem. This points to this residue as being critically important in the hydrolysis of this class of beta-lactam substrate. This is further supported by flexible-docking studies of imipenem with in silico-generated Gly170Asn and Gly170Ser mutant GES-1 enzymes designed to mimic the active sites of imipenem-hydrolyzing point mutants GES-2 and GES-5. C1 Stanford Univ, Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94305 USA. Univ Notre Dame, Dept Chem & Biochem, Notre Dame, IN 46556 USA. Calif State Univ Fullerton, Dept Chem & Biochem, Fullerton, CA 92634 USA. Calif State Univ Fullerton, Wm Keck Fdn Ctr Mol Struct, Fullerton, CA 92634 USA. RP Smith, CA (reprint author), Stanford Univ, Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94305 USA. EM csmith@slac.stanford.edu NR 48 TC 24 Z9 26 U1 4 U2 8 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD SEP PY 2007 VL 63 BP 982 EP 992 DI 10.1107/S0907444907036955 PN 9 PG 11 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 206ES UT WOS:000249167300007 PM 17704567 ER PT J AU MacRae, IJ Doudna, JA AF MacRae, Ian J. Doudna, Jennifer A. TI An unusual case of pseudo-merohedral twinning in orthorhombic crystals of Dicer SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID MOLECULAR-GRAPHICS PROJECT; RNA INTERFERENCE; SOFTWARE AB The crystal structure of the enzyme Dicer from Giardia intestinalis was solved to 3.3 angstrom resolution by MAD using crystals belonging to space group P2(1)2(1)2 [Macrae et al. (2006), Science, 311, 195-198]. These crystals were derived from crystals that diffracted X-rays to 3.0 angstrom resolution but were refractory to structure determination because they were twinned. It is shown here that the original Dicer crystals represent an unusual case of perfect pseudo-merohedral twinning of orthorhombic crystals. Before the twinning problem was overcome, it was possible to calculate a low-resolution electron-density map in space group P4(1) that was used to build a partial molecular model. Experimental phases were sufficient to identify heavy-atom sites that indicated space-group inconsistency, leading to identification of the true space group. This information guided the search for different crystallization conditions that yielded untwinned crystals and ultimately a fully interpretable electron-density map. C1 Univ Calif Berkeley, Dept Mol & Cell Biol, Howard Hughes Med Inst, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Howard Hughes Med Inst, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Doudna, JA (reprint author), Univ Calif Berkeley, Dept Mol & Cell Biol, Howard Hughes Med Inst, Berkeley, CA 94720 USA. EM doudna@berkeley.edu NR 23 TC 13 Z9 14 U1 0 U2 3 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD SEP PY 2007 VL 63 BP 993 EP 999 DI 10.1107/S0907444907036128 PN 9 PG 7 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 206ES UT WOS:000249167300008 PM 17704568 ER PT J AU Liu, XY Hanson, L Langan, P Viola, RE AF Liu, Xuying Hanson, Leif Langan, Paul Viola, Ronald E. TI The effect of deuteration on protein structure: a high-resolution comparison of hydrogenous and perdeuterated haloalkane dehalogenase SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID SITE-DIRECTED MUTAGENESIS; XANTHOBACTER-AUTOTROPHICUS GJ10; RAY CRYSTALLOGRAPHIC ANALYSIS; NEUTRON-DIFFRACTION; CYTOCHROME P450CAM; REACTION-MECHANISM; SUBSTRATE RANGE; REFINEMENT; STABILITY AB Haloalkane dehalogenase from Xanthobacter autotrophicus (XaDHL) was overexpressed under different isotopic conditions to produce fully hydrogenous (h-XaDHL) and perdeuterated (d-XaDHL) enzyme forms. Deuterium atoms at labile positions were allowed to back-exchange during purification and hydrogenous solutions were used for crystallization. Optimal crystals of h-XaDHL and d-XaDHL were obtained under different pH conditions (pH 6.0 and 4.6, respectively) but had similar P2(1)2(1)2 unit cells. X-ray diffraction data were refined to 1.53 angstrom (h-XaDHL) and 1.55 angstrom (d-XaDHL) with excellent overall statistics. The conformations of h-XaDHL and d-XaDHL are similar, with slightly altered surface regions because of different packing environments, and h-XaDHL is found to have a more hydrophobic core than d-XaDHL. The active site of h-XaDHL is similar to those of previously determined structures, but the active site of d-XaDHL unexpectedly has some crucial differences. Asp124, the primary nucleophile in the hydrolysis of haloalkane substrates, is displaced from its position in h-XaDHL and rotates to form a hydrogen bond with His289. As a consequence, the water molecule proposed to function as the nucleophile in the next catalytic step is excluded from the active site. This is the first observation of this unusual active-site configuration, which is obtained as a result of perdeuteration that decreases the hydrophobicity of the enzyme, therefore shifting the optimal pH of crystallization. This d-XaDHL structure is likely to represent the termination state of the catalytic reaction and provides an explanation for the acid inhibition of XaDHL. These results underline the importance of carefully verifying the assumption that isotopic substitution does not produce significant structural changes in protein structures. C1 Univ Toledo, Dept Chem, Toledo, OH 43606 USA. Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87544 USA. RP Viola, RE (reprint author), Univ Toledo, Dept Chem, Toledo, OH 43606 USA. EM ron.viola@utoledo.edu RI Hanson, Bryant Leif/F-8007-2010; Viola, Ronald/C-5904-2011; liu, xuying/G-7258-2012; Langan, Paul/N-5237-2015 OI Hanson, Bryant Leif/0000-0003-0345-3702; Langan, Paul/0000-0002-0247-3122 NR 33 TC 28 Z9 28 U1 0 U2 11 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD SEP PY 2007 VL 63 BP 1000 EP 1008 DI 10.1107/S0907444907037705 PN 9 PG 9 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 206ES UT WOS:000249167300009 PM 17704569 ER PT J AU Moiseeva, N Allaire, M AF Moiseeva, Natalia Allaire, Marc TI Using barium ions for heavy-atom derivatization and phasing of xylanase II from Trichoderma longibrachiatum SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID QUICK-SOAK METHOD; ANOMALOUS SCATTERING; DERIVATIVES; RESOLUTION; REFINEMENT; PROTEINS; SULFUR; XENON; MAD AB This paper describes the use of barium chloride to produce a heavy-atom derivative of xylanase II crystals from Trichoderma longibrachiatum, which was obtained either by cocrystallization or soaking. SAD phasing led to interpretable electron-density maps that allowed unambiguous chain tracing. In the best case, with a data set collected at 9.5 keV, 88% of the residues were built, with 83% of the side chains assigned. The barium ions are found to mainly interact with main-chain carbonyl groups and water molecules. It is suggested that barium ions could also be used as a potential anomalous scatterer in the quick cryosoaking procedure for phasing. C1 Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Allaire, M (reprint author), Brookhaven Natl Lab, Natl Synchrotron Light Source, Bldg 725D, Upton, NY 11973 USA. EM allaire@bnl.gov FU NIGMS NIH HHS [GM-0080] NR 28 TC 3 Z9 4 U1 0 U2 1 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD SEP PY 2007 VL 63 BP 1025 EP 1028 DI 10.1107/S090744490703418X PN 9 PG 4 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 206ES UT WOS:000249167300013 PM 17704573 ER PT J AU Fuentes-Silva, D Mendoza-Hernandez, G Stojanoff, V Palomares, LA Zenteno, E Torres-Larios, A Rodriguez-Romero, A AF Fuentes-Silva, D. Mendoza-Hernandez, G. Stojanoff, V. Palomares, L. A. Zenteno, E. Torres-Larios, A. Rodriguez-Romero, A. TI Crystallization and identification of the glycosylated moieties of two isoforms of the main allergen Hev b 2 and preliminary X-ray analysis of two polymorphs of isoform II SO ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY COMMUNICATIONS LA English DT Article ID NATURAL-RUBBER LATEX; HEVEA-BRASILIENSIS; MAJOR ALLERGEN; OLIGOSACCHARIDES; ANTIBODIES; EPITOPES; POLLEN AB Latex from Hevea brasiliensis contains several allergenic proteins that are involved in type I allergy. One of them is Hev b 2, which is a beta-1,3-glucanase enzyme that exists in different isoforms with variable glycosylation content. Two glucanase isoforms were isolated from trees of the GV-42 clone by gel filtration, affinity and ion-exchange chromatography. Isoform I had a carbohydrate content of about 20%, with N-linked N-acetyl-glucosamine, N-acetyl-galactosamine, fucose and galactose residues as the main sugars, while isoform II showed 6% carbohydrate content constisting of N-acetyl-glucosamine, fucose, mannose and xylose. Both isoforms were crystallized by the hanging-drop vapour-diffusion method. Isoform I crystals were grown using 0.2 M trisodium citrate dihydrate, 0.1 M Na HEPES pH 7.5 and 20%( v/ v) 2-propanol, but these crystals were not appropriate for data collection. Isoform II crystals were obtained under two conditions and X-ray diffraction data were collected from both. In the first condition ( 0.2 M trisodium citrate, 0.1 M sodium cacodylate pH 6.5, 30% 2-propanol), crystals belonging to the tetragonal space group P4(1) with unit-cell parameters a = b = 150.17, c = 77.41 angstrom were obtained. In the second condition [ 0.2 M ammonium acetate, 0.1 M trisodium citrate dihydrate pH 5.6, 30%( w/ v) polyethylene glycol 4000] the isoform II crystals belonged to the monoclinic space group P2(1), with unit-cell parameters a = 85.08, b = 89.67, c = 101.80 angstrom, beta = 113.6 degrees. Preliminary analysis suggests that there are four molecules of isoform II in both asymmetric units. C1 Univ Nacl Autonoma Mexico, Inst Quim, Mexico City 04510, DF, Mexico. Univ Nacl Autonoma Mexico, Fac Med, Mexico City 04510, DF, Mexico. Natl Synchrotron Light Source, Brookhaven Natl Lab, Upton, NY USA. Univ Nacl Autonoma Mexico, Inst Biotecnol, Mexico City 04510, DF, Mexico. Univ Nacl Autonoma Mexico, Inst Fisiol Celular, Mexico City 04510, DF, Mexico. RP Rodriguez-Romero, A (reprint author), Univ Nacl Autonoma Mexico, Inst Quim, Circuito Exterior S-N,Cuidad Univ, Mexico City 04510, DF, Mexico. EM adela@servidor.unam.mx RI Palomares, Laura/A-1082-2008; stojanoff, vivian /I-7290-2012; RODRIGUEZ-ROMERO, ADELA/C-7723-2015; OI stojanoff, vivian /0000-0002-6650-512X; Torres-Larios, Alfredo/0000-0002-0702-350X FU NIGMS NIH HHS [GM0080, Y01 GM000080] NR 34 TC 4 Z9 5 U1 0 U2 0 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 2053-230X J9 ACTA CRYSTALLOGR F JI Acta Crystallogr. F-Struct. Biol. Commun. PD SEP PY 2007 VL 63 BP 787 EP 791 DI 10.1107/S1744309107039838 PN 9 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 205ZS UT WOS:000249154300019 PM 17768356 ER PT J AU Shen, TD Schwarz, RB Feng, S Swadener, JG Huang, JY Tang, M Zhang, H Vogel, SC Zhao, YS AF Shen, T. D. Schwarz, R. B. Feng, S. Swadener, J. G. Huang, J. Y. Tang, M. Zhang, Hanzhong Vogel, S. C. Zhao, Yusheng TI Effect of solute segregation on the strength of nanocrystalline alloys: Inverse Hall-Petch relation SO ACTA MATERIALIA LA English DT Article DE inverse hall-petch effect; nanocrystalline; mechanical property; hardening by annealing; grain boundary segregation ID GRAIN-SIZE; MECHANICAL-PROPERTIES; PLASTIC-DEFORMATION; BEHAVIOR; MODEL; IRON; DISLOCATIONS; SIMULATION; DEPENDENCE; CONTRAST AB We have used a high-energy ball mill to prepare single-phased nanocrystalline Fe, Fe90Ni10, Fe85Al4Si11, Ni99Fe1 and Ni90Fe10 powders. We then increased their grain sizes by annealing. We found that a low-temperature anneal (T < 0.4 T-m) softens the elemental nanocrystalline Fe but hardens both the body-centered cubic iron- and face-centered cubic nickel-based solid solutions, leading in these alloys to an inverse Hall-Petch relationship. We explain this abnormal Hall-Petch effect in terms of solute segregation to the grain boundaries of the nanocrystalline alloys. Our analysis can also explain the inverse Hall-Petch relationship found in previous studies during the thermal anneal of ball-milled nanocrystalline Fe (containing similar to 1.5 at.% impurities) and electrodeposited nanocrystalline Ni (containing similar to 1.0 at.% impurities). Published by Elsevier Ltd on behalf of Acta Materialia Inc. C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Sandia Natl Labs, Ctr Integrated Nanotechnol, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, LANSCE Div, Los Alamos, NM 87545 USA. RP Shen, TD (reprint author), Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. EM tdshen@lanl.gov RI Huang, Jianyu/C-5183-2008; Lujan Center, LANL/G-4896-2012; OI Zhang, Jianzhong/0000-0001-5508-1782; Vogel, Sven C./0000-0003-2049-0361 NR 42 TC 50 Z9 53 U1 5 U2 34 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD SEP PY 2007 VL 55 IS 15 BP 5007 EP 5013 DI 10.1016/j.actamat.2007.05.018 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 216RG UT WOS:000249896100008 ER PT J AU LaGrange, T Campbell, GH Turchi, PEA King, WE AF LaGrange, T. Campbell, G. H. Turchi, P. E. A. King, W. E. TI Rapid phase transformation kinetics on a nanoscale: Studies of the alpha -> beta transformation in pure, nanocrystalline Ti using the nanosecond dynamic transmission electron microscope SO ACTA MATERIALIA LA English DT Article DE transmission electron microscopy; titanium; martensitic phase transformation; phase transformation kinetics; nanocrystalline microstructure ID ISOTHERMAL MARTENSITIC-TRANSFORMATION; NUCLEATION; TITANIUM; DIFFRACTION; MOBILITY; ALLOYS AB Using the unique capabilities and high time resolution of dynamic transmission electron microscopy (DTEM), the fast kinetics of alpha -> beta-phase transformation in nanocrystalline Ti films were investigated using single-shot electron diffraction and bright-field TEM images. From quantitative analysis of the diffraction patterns, the transformation rates were determined for temperatures between transition start (1155 K) and melt temperature (1943 K). The experimental data were summarized in a time-temperature-transformation (TTT) curve with nanosecond time resolution. Theoretical TTT curves were calculated using analytical models for isothermal martensite and available thermodynamic data. Above 1300 K, there is excellent agreement between the experiment and the discrete-obstacle interaction model, suggesting that the nucleation rate and thermally assisted motion of the martensite interface are controlled by interface-solute atom interactions. However, theory predicts much slower transformation rates near the transition temperature than experiment. Experimental data fits using the Pati-Cohen model suggests that an increase in autocatalytic nucleation may partially account for the fast transformation rates at lower temperatures. Published by Elsevier Ltd on behalf of Acta Materialia Inc. C1 Lawrence Livermore Natl Lab, Mat Sci & Technol Div, Chem Mat & Life Sci Directorate, Livermore, CA 94550 USA. RP LaGrange, T (reprint author), Lawrence Livermore Natl Lab, Mat Sci & Technol Div, Chem Mat & Life Sci Directorate, Livermore, CA 94550 USA. EM lagrange2@llnl.gov RI Campbell, Geoffrey/F-7681-2010 NR 31 TC 30 Z9 30 U1 3 U2 28 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD SEP PY 2007 VL 55 IS 15 BP 5211 EP 5224 DI 10.1016/j.actamat.2007.05.043 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 216RG UT WOS:000249896100028 ER PT J AU Krishnamurthy, R Srolovitz, DJ Mendelev, MI AF Krishnamurthy, R. Srolovitz, D. J. Mendelev, M. I. TI Anomalous diffusion in dilute solid solutions SO ACTA MATERIALIA LA English DT Article DE MC simulation; molecular statics simulation; impurities; short-range ordering ID MONTE-CARLO-SIMULATION; RANDOM ALLOY; AL; MODEL AB Diffusion in metals and alloys encapsulates many different physical phenomena and a range of time and length scales, and consequently, a hierarchical combination of simulation methods is required to study diffusion. We develop such methods to study the role interaction among defects and diffusants, and local association effects, play in diffusion in metals. We use Fe impurity diffusion in Al as an example. Using recently developed, accurate, interatomic potentials for the Fe-Al system, we calculate migration energies for atom-vacancy exchange in a variety of local atomic configurations, using lattice statics methods. These are used in a kinetic Monte-Carlo framework to calculate diffusivities. Two different activation regimes are observed at temperatures above and below 550 K. We explain this anomalous, non-Arrhenius behavior of the diffusion activation energy in terms of the interaction among vacancies and Fe atoms, and local association/ordering effects. (C) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. C1 Caterpillar Inc, Ctr Tech, TC K, Mat Modeling Grp,Technol & Solut Div, Mossville, IL 61552 USA. Princeton Univ, Princeton Inst Sci & Technol Mat, Dept Engn Mech, Princeton, NJ 08542 USA. Yeshiva Univ, Yeshiva Coll, New York, NY 10033 USA. Ames Lab, Ames, IA USA. RP Krishnamurthy, R (reprint author), Caterpillar Inc, Ctr Tech, TC K, Mat Modeling Grp,Technol & Solut Div, POB 1875, Mossville, IL 61552 USA. EM krishnamurthy.ram@gmail.com; srol@yu.edu; mendelev@ameslab.gov RI Krishnamurthy, Ram/F-6213-2011 NR 28 TC 3 Z9 3 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD SEP PY 2007 VL 55 IS 15 BP 5289 EP 5296 DI 10.1016/j.actamat.2007.06.001 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 216RG UT WOS:000249896100035 ER PT J AU Jones, JL Motahari, SM VarlioglU, M Lienert, U Bernier, JV Hoffman, M Ustundag, E AF Jones, Jacob L. Motahari, S. Maziar VarlioglU, Mesut Lienert, Ulrich Bernier, Joel V. Hoffman, Mark Uestuendag, Ersan TI Crack tip process zone domain switching in a soft lead zirconate titanate ceramic SO ACTA MATERIALIA LA English DT Article DE ferroelectricity; fracture; ceramics; toughness; X-ray diffraction (XRD) ID X-RAY-DIFFRACTION; R-CURVE BEHAVIOR; FERROELECTRIC CERAMICS; FERROELASTIC MATERIALS; LATTICE STRAIN; TEXTURE; STRESS; FIELDS; PZT AB Non-180 degrees domain switching leads to fracture toughness enhancement in ferroelastic materials. Using a high-energy synchrotron X-ray source and a two-dimensional detector in transmission geometry, non-180 degrees domain switching and crystallographic lattice strains were measured in situ around a crack tip in a soft tetragonal lead zirconate titanate ceramic. At K-I = 0.71 MPa m(1/2) and below the initiation toughness, the process zone size, spatial distribution of preferred domain orientations, and lattice strains near the crack tip are a strong function of direction within the plane of the compact tension specimen. Deviatoric stresses and strains calculated using a finite element model and projected to the same directions measured in diffraction correlate with the measured spatial distributions and directional dependencies. Some preferred orientations remain in the crack wake after the crack has propagated; within the crack wake, the tetragonal 001 axis has a preferred orientation both perpendicular to the crack face and toward the crack front. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ New S Wales, Sch Mat Sci & Engn, Sydney, NSW 2052, Australia. RP Jones, JL (reprint author), Univ Florida, Dept Mat Sci & Engn, POB 116400, Gainesville, FL 32611 USA. EM jjones@mse.ufl.edu RI Jones, Jacob/A-8361-2008; Ustundag, Ersan/C-1258-2009; Hoffman, Mark/E-5021-2012 OI Ustundag, Ersan/0000-0002-0812-7028; Hoffman, Mark/0000-0003-2927-1165 NR 33 TC 35 Z9 35 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 EI 1873-2453 J9 ACTA MATER JI Acta Mater. PD SEP PY 2007 VL 55 IS 16 BP 5538 EP 5548 DI 10.1016/j.actamat.2007.06.012 PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 211SC UT WOS:000249542600023 ER PT J AU Hou, PY Paulikas, AP Veal, BW Smialek, JL AF Hou, P. Y. Paulikas, A. P. Veal, B. W. Smialek, J. L. TI Thermally grown Al(2)O(3) on a H(2)-annealed Fe(3)Al alloy: Stress evolution and film adhesion SO ACTA MATERIALIA LA English DT Article DE oxidation; stresses; adhesion; interface segregation; buckling ID HIGH-TEMPERATURE OXIDATION; OXIDE SCALE ADHERENCE; ALUMINA SCALES; SULFUR SEGREGATION; TRANSIENT OXIDATION; REACTIVE ELEMENT; BEHAVIOR; IRON; KINETICS; YTTRIUM AB Stress evolution in Al(2)O(3) films grown on a Fe(3)Al-based alloy, with or without a prior H(2)-anneal heat treatment, was followed in situ with a synchrotron X-ray source at 1000 and 1100 degrees C and during cooling. These results are complimented by studies of oxidation kinetics, the scale/alloy interfacial chemistry, and the oxide, alloy and interface microstructures. The H(2)-anneal reduced the sample sulfur impurity to less than 1 ppm, significantly improved scale adhesion, maintained a planar scale/alloy interface, but did not demonstrably affect the oxidation rate or the growth stress development. On the untreated alloy, interface wrinkling was a major stress relief mechanism, but for the H(2)-annealed samples it was oxide creep with contribution from alloy grain boundary sliding. The interface strength and the extent of oxide spallation were closely related to the amount of sulfur segregated at the interface. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Argonne Natl Lab, Argonne, IL 60439 USA. NASA, Glen Res Ctr, Cleveland, OH 44135 USA. RP Hou, PY (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM pyhou@lbl.gov NR 60 TC 21 Z9 21 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD SEP PY 2007 VL 55 IS 16 BP 5601 EP 5613 DI 10.1016/j.actamat.2007.06.018 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 211SC UT WOS:000249542600029 ER PT J AU Eidenbenz, S Hansson, AA Ramaswamy, V Reidys, CM AF Eidenbenz, S. Hansson, A. A. Ramaswamy, V. Reidys, C. M. TI On a new class of load balancing network protocols SO ADVANCES IN COMPLEX SYSTEMS LA English DT Article DE sequential dynamical system; TCP; network; protocol ID SEQUENTIAL DYNAMICAL-SYSTEMS AB In this paper we study a new class of generic, parametrized, locally load-sensing (LLS) network-routing protocols over simple graphs, Y. These protocols are Y-"local" in the sense that they transmit packets only between Y-adjacent vertices and LLS since they base their "routing decisions" dynamically on queue-sizes of their neighbors and their relative distance to the destination. In the system each vertex has specific data-queues indexed by its respective Y-neighbors. The state of a vertex then consists of the collection of queue-sizes. The data-transmission protocols are formally specified in the framework of sequential dynamical systems, which allows us to categorize and classify our experiments. We will investigate the following scenario: for fixed Y we assume a single source/destination pair to be given and a system-update then consists of the collection of local protocol updates according to some fixed permutation of the Y-vertices. We then iterate the system-updates and thereby obtain the time evolution of the queue-sizes of the vertices. We will present and discuss results on the evolution of the load, i.e. the total number of packets in the network, the throughput, i.e. the rate at which packets arrive at the destination, and study the dependence of the queue-size dynamics on various other system parameters. In particular, we will analyze update schedule dependency and the impact of queue-capacity on system stability. We will show that our protocols can adapt and dynamically utilize new routes in a fixed network. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Reidys, CM (reprint author), Los Alamos Natl Lab, CCS-3, Los Alamos, NM 87545 USA. EM duck@santafe.edu OI Eidenbenz, Stephan/0000-0002-2628-1854 NR 15 TC 0 Z9 0 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0219-5259 EI 1793-6802 J9 ADV COMPLEX SYST JI Adv. Complex Syst. PD SEP PY 2007 VL 10 IS 3 BP 359 EP 377 DI 10.1142/S0219525907001148 PG 19 WC Mathematics, Interdisciplinary Applications; Multidisciplinary Sciences SC Mathematics; Science & Technology - Other Topics GA 229RV UT WOS:000250822800005 ER PT J AU Lee, SY Carle, SF Fogg, GE AF Lee, Si-Yong Carle, Steven F. Fogg, Graham E. TI Geologic heterogeneity and a comparison of two geostatistical models: Sequential Gaussian and transition probability-based geostatistical simulation SO ADVANCES IN WATER RESOURCES LA English DT Article DE geologic heterogeneity; geostatistical simulation; connectivity; drawdown response ID ALLUVIAL AQUIFER SYSTEM; STATE GROUNDWATER-FLOW; POROUS-MEDIA; HYDRAULIC CONDUCTIVITY; STOCHASTIC-ANALYSIS; SOLUTE TRANSPORT; DIMENSIONAL SIMULATIONS; NUMERICAL-SIMULATION; BOUNDED DOMAIN; MACRODISPERSION AB A covariance-based model-fitting approach is often considered valid to represent field spatial variability of hydraulic properties. This study examines the representation of geologic heterogeneity in two types of geostatistical models under the same mean and spatial covariance structure, and subsequently its effect on the hydraulic response to a pumping test based on 3D high-resolution numerical simulation and field data. Two geostatistical simulation methods, sequential Gaussian simulation (SGS) and transition probability indicator simulation (TPROGS) were applied to create conditional realizations of alluvial fan aquifer systems in the Lawrence Livermore National Laboratory (LLNL) area. The simulated K fields were then used in a numerical groundwater flow model to simulate a pumping test performed at the LLNL site. Spatial connectivity measures of high-K materials (channel facies) captured connectivity characteristics of each geostatistical model and revealed that the TPROGS model created an aquifer (channel) network having greater lateral connectivity. SGS realizations neglected important geologic structures associated with channel and overbank (levee) facies, even though the covariance model used to create these realizations provided excellent fits to sample covariances computed from exhaustive samplings of TPROGS realizations. Observed drawdown response in monitoring wells during a pumping test and its numerical simulation shows that in an aquifer system with strongly connected network of high-K materials, the Gaussian approach could not reproduce a similar behavior in simulated drawdown response found in TPROGS case. Overall, the simulated drawdown responses demonstrate significant disagreement between TPROGS and SGS realizations. This study showed that important geologic characteristics may not be captured by a spatial covariance model, even if that model is exhaustively determined and closely fits the exponential function. (c) 2007 Elsevier Ltd. All rights reserved. C1 Univ Calif Davis, Dept Geol, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lee, SY (reprint author), SUNY Buffalo, Dept Geol, Buffalo, NY 14260 USA. EM sylee@ucdavis.edu; carle@oyster.llnl.gov; gefogg@ucdavis.edu NR 71 TC 62 Z9 65 U1 10 U2 41 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0309-1708 J9 ADV WATER RESOUR JI Adv. Water Resour. PD SEP PY 2007 VL 30 IS 9 BP 1914 EP 1932 DI 10.1016/j.advwatres.2007.03.005 PG 19 WC Water Resources SC Water Resources GA 195TV UT WOS:000248435700004 ER PT J AU Bond, RB Ober, CC Knupp, PM Bova, SW AF Bond, Ryan B. Ober, Curtis C. Knupp, Patrick M. Bova, Steven W. TI Manufactured solution for computational fluid dynamics boundary condition verification SO AIAA JOURNAL LA English DT Article ID NAVIER-STOKES EQUATIONS; SCHEMES AB Order-of-accuracy verification is necessary to ensure that software correctly solves a given set of equations. One method for verifying the order of accuracy of a code is the method of manufactured solutions. This study documents the development of a manufactured solution that allows verification of not only the Euler, Navier-Stokes, and Reynolds-averaged Navier-Stokes equation sets, but also some of their associated boundary conditions: slip, no-slip (adiabatic and isothermal), and outflow (subsonic, supersonic, and mixed). To demonstrate the usefulness of this manufactured solution, it has been used for order-of-accuracy verification in a compressible computational fluid dynamics code. All of the results shown are on skewed, nonuniform, three-dimensional meshes. The manufactured solution and sequence of meshes are designed to allow asymptotic results to be obtained with reasonable computational cost. In addition to the order of accuracy of the full code for various equation sets and boundary conditions, the order of accuracy of code portions used to calculate solution gradients has been measured as well. C1 Sandia Natl Labs, Aerosci Dept, Albuquerque, NM 87185 USA. RP Bond, RB (reprint author), Sandia Natl Labs, Aerosci Dept, POB 5800, Albuquerque, NM 87185 USA. EM rbbond@sandia.gov NR 26 TC 13 Z9 13 U1 1 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD SEP PY 2007 VL 45 IS 9 BP 2224 EP 2236 DI 10.2514/1.28099 PG 13 WC Engineering, Aerospace SC Engineering GA 210JE UT WOS:000249451700012 ER PT J AU Kastengren, AL Dutton, JC Elliott, GS AF Kastengren, Alan L. Dutton, J. Craig Elliott, Gregory S. TI Coherent structure eduction and convection velocity in compressible blunt-body wakes SO AIAA JOURNAL LA English DT Article ID LARGE-SCALE STRUCTURES; PARTICLE IMAGE VELOCIMETRY; BACKWARD-FACING STEP; MIXING LAYERS; SHEAR-LAYER; BASE-FLOW; EVOLUTION; ENTRAINMENT; TURBULENCE; GROWTH AB An iterative eduction procedure has been developed to study coherent structures in blunt-base cylinder-wakes at 0 and 10 deg angles of attack to an M = 2.46 freestream flow. The eduction procedure uses an initial wavelet pattern to find candidate cohered structures of a particular scale and then uses the average intensity pattern of the educed structures to create an updated pattern. This iterative procedure continues until the average structure converges, indicating that a self-consistent intensity pattern has been described. Using this eduction procedure, the average appearance of the structures is described. Moreover, a convection velocity measurement is made by directly tracking individual coherent structures, unlike conventional imaging-based convection velocity measurements, which are not conditioned on coherent structures. The evolutionary trends of the structures are also quantified. The coherent structure averages show many of the same trends found in more conventional autocorrelation analysis. For example, the structures are inclined toward the freestream flow direction, and the angle of this inclination is affected by the recompression and reattachment processes. Convection velocity measurements show that the convection velocity is dependent on the transverse position of the structure in the shear layer, particularly for small structures. Finally, the coherent structures evolve in such a way that they become poorly representative of the average coherent structure pattern within 5-15 mu s after being first identified. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Texas, Arlington, TX 76019 USA. Univ Illinois, Urbana, IL 61801 USA. RP Kastengren, AL (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 30 TC 2 Z9 2 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD SEP PY 2007 VL 45 IS 9 BP 2299 EP 2311 DI 10.2514/1.29221 PG 13 WC Engineering, Aerospace SC Engineering GA 210JE UT WOS:000249451700019 ER PT J AU Leitner, T Dazza, MC Ekwalanga, M Apetrei, C Saragosti, S AF Leitner, Thomas Dazza, Marie-Christine Ekwalanga, Michel Apetrei, Cristian Saragosti, Sentob TI Sequence diversity among chimpanzee simian immunodeficiency viruses (SIVcpz) suggests that SIVcpzPts was derived from SIVcpzPtt through additional recombination events SO AIDS RESEARCH AND HUMAN RETROVIRUSES LA English DT Article ID MANDRILLUS-SPHINX; GENETIC DIVERSITY; WILD CHIMPANZEE; INFECTION; TROGLODYTES; LENTIVIRUS; HIV-1; POPULATIONS; AFRICA; ORIGIN AB Only two of four chimpanzee subspecies (Pan troglodytes), P. troglodytes troglodytes (P.t.t.) and P. troglodytes schweinfurthii (P.t.s.), appear to carry specific simian immunodeficiency viruses (SIVs). We identified genomic features indicating that SIVcpzPtt and SIVcpzPts may have partly different evolutionary histories. A maximum likelihood test to discriminate between hypotheses of a common versus separate origin of SIVcpzPtt and SIVcpzPts revealed three putative regions of separate histories. Thus, after the P.t.t. and P.t.s. split, SIV superinfection led to further recombination resulting in the emergence of SIVcpzPts. This shows that there have been multiple SIV transfers to chimpanzees at different times in their evolution. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Hop Bichat Claude Bernard, INSERM, IMEA, U552, F-75877 Paris, France. Univ Lubumbashi, Katanga, Congo. Tulane Univ, Ctr Hlth, New Orleans, LA 70118 USA. Tulane Natl Primate Res Ctr, Covington, LA USA. RP Leitner, T (reprint author), Los Alamos Natl Lab, Grp T-10,MS K710, Los Alamos, NM 87545 USA. EM tkl@lanl.gov FU NIAID NIH HHS [Y1-AI-1500-05] NR 22 TC 7 Z9 7 U1 0 U2 0 PU MARY ANN LIEBERT INC PI NEW ROCHELLE PA 140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USA SN 0889-2229 J9 AIDS RES HUM RETROV JI Aids Res. Hum. Retrovir. PD SEP PY 2007 VL 23 IS 9 BP 1114 EP 1118 DI 10.1089/aid.2007.0071 PG 5 WC Immunology; Infectious Diseases; Virology SC Immunology; Infectious Diseases; Virology GA 219BC UT WOS:000250058700008 PM 17919106 ER PT J AU Jackson, JD Heras, JA AF Jackson, J. D. Heras, J. A. TI Comment on "Preacceleration without radiation: The nonexistence of preradiation phenomenon," SO AMERICAN JOURNAL OF PHYSICS LA English DT Editorial Material C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Jackson, JD (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 8 TC 7 Z9 7 U1 1 U2 3 PU AMER ASSOC PHYSICS TEACHERS AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD SEP PY 2007 VL 75 IS 9 BP 844 EP 845 DI 10.1119/1.2733681 PG 2 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 204EC UT WOS:000249025400017 ER PT J AU Audigane, P Gaus, I Czernichowski-Lauriol, I Pruess, K Xu, TF AF Audigane, Pascal Gaus, Irina Czernichowski-Lauriol, Isabelle Pruess, Karsten Xu, Tianfu TI Two-dimensional reactive transport modeling of CO2 injection in a saline Aquifer at the Sleipner site, North Sea SO AMERICAN JOURNAL OF SCIENCE LA English DT Article ID GEOCHEMICAL TRANSPORT; CARBON-DIOXIDE; NUMERICAL-SIMULATION; GREENHOUSE GASES; MULTIPHASE FLOW; FLUID-FLOW; DISPOSAL; DISSOLUTION; SEQUESTRATION; KINETICS AB This paper presents a 2D reactive transport model of long-term geological storage of carbon dioxide. A data set from the Utsira formation in Sleipner (North Sea) is utilized for geochemical simulation, while the aquifer is approximated as a 2D cylindrically symmetric system. Using the reactive transport code TOUGHREACT, a 25 year injection scenario followed by a 10,000 year storage period are simulated. Supercritical CO2 migration, dissolution of the CO2 in the brine, and geochemical reactions with the host rock are considered in the model. Two mineralogical assemblages are considered in the Utsira formation, a sand formation that is highly permeable and a shale formation representing four semi-permeable layers in the system that reduce the upward migration of the supercritical CO2. The impacts of mineral dissolution and precipitation on porosity are calculated. Furthermore, the 2D cylindrical geometry of the mesh allows simulating both the upward migration of the supercritical gas bubble as well as the downward migration of the brine containing dissolved CO2. A mass balance of the CO2 stored in, respectively, the supercritical phase, dissolved in the aqueous phase, and sequestered in solid mineral phases (carbonate precipitation) is calculated over time. Simulations with lower residual gas saturation and with different mesh refinement are also performed to test the sensitivity on mass balance estimates. C1 Bur Rech Geol & Minieres, French Geol Survey, F-45060 Orleans, France. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Audigane, P (reprint author), Bur Rech Geol & Minieres, French Geol Survey, BP 6009, F-45060 Orleans, France. EM p.audiganc@brgm.fr NR 75 TC 150 Z9 159 U1 1 U2 45 PU AMER JOURNAL SCIENCE PI NEW HAVEN PA YALE UNIV, PO BOX 208109, NEW HAVEN, CT 06520-8109 USA SN 0002-9599 EI 1945-452X J9 AM J SCI JI Am. J. Sci. PD SEP PY 2007 VL 307 IS 7 BP 974 EP 1008 DI 10.2475/07.2007.02 PG 35 WC Geosciences, Multidisciplinary SC Geology GA 235JF UT WOS:000251229100002 ER PT J AU Cooley, PW Chen, T Wallace, DB Hopwood, F Gooley, A Svec, F AF Cooley, Patrick W. Chen, Ting Wallace, David B. Hopwood, Femia Gooley, Andrew Svec, Frantisek TI A microdispenser for LC separation and MALDI MS analysis SO AMERICAN LABORATORY LA English DT Article ID ASSISTED-LASER-DESORPTION/IONIZATION; MASS-SPECTROMETRY; PROTEOMICS; CHROMATOGRAPHY; IONIZATION; PROTEINS; ONLINE C1 MicroFab Technologies Inc, Plano, TX 75074 USA. Proteome Syst Ltd, N Ryde, NSW, Australia. Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Cooley, PW (reprint author), MicroFab Technologies Inc, 1104 Summit Ave,Ste 110, Plano, TX 75074 USA. EM patrick.cooley@microfab.com NR 15 TC 0 Z9 0 U1 0 U2 5 PU INT SCIENTIFIC COMMUN INC PI SHELTON PA PO BOX 870, 30 CONTROLS DRIVE, SHELTON, CT 06484-0870 USA SN 0044-7749 J9 AM LAB JI Am. Lab. PD SEP PY 2007 VL 39 IS 17 SU N BP 27 EP 29 PG 3 WC Chemistry, Analytical; Instruments & Instrumentation SC Chemistry; Instruments & Instrumentation GA 239UV UT WOS:000251544500008 ER PT J AU Hadjar, O Wang, P Futrell, JH Dessiaterik, Y Zhu, ZH Cowin, JP Iedema, MJ Laskin, J AF Hadjar, Omar Wang, Peng Futrell, Jean H. Dessiaterik, Yury Zhu, Zihua Cowin, James P. Iedema, Martin J. Laskin, Julia TI Design and performance of an instrument for soft landing of Biomolecular ions on surfaces SO ANALYTICAL CHEMISTRY LA English DT Article ID ASSEMBLED MONOLAYER SURFACES; IONIZATION MASS-SPECTROMETRY; PARTICLE-INDUCED DESORPTION; SECONDARY-ION; INDUCED DISSOCIATION; PREPARATIVE SOFT; FUNNEL INTERFACE; POLYATOMIC IONS; MOLECULAR-IONS; GAS-PHASE AB A new ion deposition apparatus was designed and constructed in our laboratory. Our research objectives were to investigate interactions of biomolecules with hydrophilic and hydrophobic surfaces and to carry out exploratory experiments aimed at highly selective deposition of spatially defined and uniquely selected biological molecules on surfaces. The apparatus includes a high-transmission electrospray ion source, a quadrupole mass filter, a bending quadrupole that deflects the ion beam and prevents neutral molecules originating in the ion source from impacting the surface, an ultrahigh vacuum (UHV) chamber for ion deposition by soft landing, and a vacuum lock system for introducing surfaces into the UHV chamber without breaking vacuum. Ex situ analysis of surfaces following soft landing of mass-selected peptide ions was performed using 15 keV Ga+ time-of-flight secondary ion mass spectrometry and grazing incidence infrared reflection-absorption spectroscopy. It is shown that these two techniques are highly complementary methods for characterization of surfaces prepared with a range of doses of mass-selected biomolecular ions. We also demonstrated that soft landing of peptide ions on surfaces can be utilized for controlled preparation of peptide films of known coverage for fundamental studies of matrix effects in SIMS. C1 Pacific NW Natl Lab, Fundamental Sci Directorate, Richland, WA 99352 USA. Environm Mol Sci Lab, Richland, WA 99352 USA. RP Laskin, J (reprint author), Pacific NW Natl Lab, Fundamental Sci Directorate, Richland, WA 99352 USA. EM Julialaskin@pnl.gov RI Zhu, Zihua/K-7652-2012; Laskin, Julia/H-9974-2012 OI Laskin, Julia/0000-0002-4533-9644 NR 44 TC 39 Z9 39 U1 1 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD SEP 1 PY 2007 VL 79 IS 17 BP 6566 EP 6574 DI 10.1021/ac070600h PG 9 WC Chemistry, Analytical SC Chemistry GA 207HT UT WOS:000249242900025 PM 17668931 ER PT J AU Zhang, H Cha, SW Yeung, ES AF Zhang, Hui Cha, Sangwon Yeung, Edward S. TI Colloidal graphite-assisted laser desorption/ionization MS and MSn of small molecules. 2. Direct profiling and MS imaging of small metabolites from fruits SO ANALYTICAL CHEMISTRY LA English DT Article ID FLIGHT MASS-SPECTROMETRY; MALDI-TOF-MS; INTERMEDIATE-PRESSURE MALDI; THIN-LAYER-CHROMATOGRAPHY; OXIDIZED CARBON NANOTUBES; DESORPTION-IONIZATION; TISSUE-SECTIONS; POROUS SILICON; FATTY-ACIDS; LIQUID-CHROMATOGRAPHY AB Due to a high background in the low-mass region, conventional MALDI is not as useful for detecting small molecules (molecular masses < 500 Da) as it is for large ones. Also, spatial inhomogeneity that is inherent to crystalline matrixes can degrade resolution in imaging mass spectrometry (IMS). In this study, colloidal graphite was investigated as an alternative matrix for laser desorption/ionization (GALDI) in IMS. We demonstrate its advantages over conventional MALDI in the detection of small molecules such as organic acids, flavonoids, and oligosaccharides. GALDI provides good sensitivity for such small molecules. The detection limit of fatty acids and flavonoids, in the negative-ion mode are in the low-femtomole range. Molecules were detected directly and identified by comparing the MS and MS/MS spectra with those of standards. Various fruits were chosen to evaluate the practical utility of GALDI since many types of small molecules are present in them. Distribution of these small molecules in the fruit was investigated by using IMS and IMS/Ms. C1 Iowa State Univ, Ames Lab, USDOE, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Yeung, ES (reprint author), Iowa State Univ, Ames Lab, USDOE, Ames, IA 50011 USA. EM yeung@ameslab.gov RI Cha, Sangwon/C-6917-2008 OI Cha, Sangwon/0000-0003-2819-3417 NR 63 TC 97 Z9 99 U1 3 U2 30 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD SEP 1 PY 2007 VL 79 IS 17 BP 6575 EP 6584 DI 10.1021/ac0706170 PG 10 WC Chemistry, Analytical SC Chemistry GA 207HT UT WOS:000249242900026 PM 17665874 ER PT J AU Logan, TC Clark, DS Stachowiak, TB Svec, F Frechet, JMJ AF Logan, Timothy C. Clark, Douglas S. Stachowiak, Timothy B. Svec, Frantisek Frechet, Jean M. J. TI Photopatterning enzymes on polymer monoliths in microfluidic devices for steady-state kinetic analysis and spatially separated multi-enzyme reactions SO ANALYTICAL CHEMISTRY LA English DT Article ID ON-A-CHIP; HYDROGEN-PEROXIDE; GLUCOSE SENSOR; PROTEIN; ASSAYS; IMMOBILIZATION; CAPILLARY; CHANNELS; MICROREACTORS; SUPPORTS AB A method for photopatterning multiple enzymes on porous polymer monoliths within microfluidic devices has been developed and used to perform spatially separated multienzymatic reactions. To reduce nonspecific adsorption of enzymes on the monolith, its pore surface was modified by graffing poly(ethylene glycol), followed by surface photoactivation and enzyme immobilization in the presence of a nonionic surfactant. Characterization of bound horseradish peroxidase (HRP) was carried out using a reaction in which the steady-state profiles of the fluorescent reaction product could be measured in situ and then analyzed using a plug-flow bioreactor model to determine the observed maximum reaction rate and Michaelis constant. The Michaelis constant of 1.9 mu mol/L agrees with previously published values. Mass-transfer limitations were evident at relatively low flow rates but were absent at higher flow rates. Sequential multienzymatic reactions were demonstrated using the patternwise assembly of two- and three-enzyme systems. Glucose oxidase (GOX) and HRP were patterned in separate regions of a single channel, and product formation was analyzed as a function of flow direction. Significant product formation occurred only in the GOX to HRP direction. A three-enzyme sequential reaction was performed using invertase, GOX, and HRP. All possible arrangements of the three enzymes were tested, but significant product formation was only observed when the enzymes were in the correct sequential order. Photopatteming enzymes on polymer monoliths provides a simple technique for preparing spatially localized multiple-enzyme microreactors capable of directional synthesis. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Coll Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Mol Foundry, Berkeley, CA 94720 USA. RP Clark, DS (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. EM clark@berkeley.edu OI Frechet, Jean /0000-0001-6419-0163 FU NIBIB NIH HHS [EB006133] NR 49 TC 84 Z9 87 U1 8 U2 56 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD SEP 1 PY 2007 VL 79 IS 17 BP 6592 EP 6598 DI 10.1021/ac070705k PG 7 WC Chemistry, Analytical SC Chemistry GA 207HT UT WOS:000249242900028 PM 17658765 ER PT J AU Laskin, J Yang, ZB Lam, C Chu, IK AF Laskin, Julia Yang, Zhibo Lam, Corey Chu, Ivan K. TI Charge-remote fragmentation of odd-electron peptide ions SO ANALYTICAL CHEMISTRY LA English DT Article ID COLLISION-INDUCED DISSOCIATION; SURFACE-INDUCED DISSOCIATION; MOLECULAR RADICAL CATIONS; IONIZATION MASS-SPECTROMETRY; GAS-PHASE DISSOCIATION; CAPTURE DISSOCIATION; PROTONATED PEPTIDES; AMINO-ACID; CYCLOTRON RESONANCE; DETACHMENT DISSOCIATION AB Comparison between the gas-phase fragmentation of odd-electron M+center dot, [M + H](2+center dot), and [M - 2H](-center dot) ions of model peptides suggests that charge-remote radical-driven fragmentation pathways play an important role in the dissociation of odd-electron peptide ions. We have found that charge-remote processes are responsible for a variety of side-chain losses from the precursor ion and some backbone fragmentation. These fragmentation pathways most likely involve hydrogen abstraction by the radical site that initiates subsequent cleavages. These findings are generally relevant to our understanding of the fragmentation patterns of odd-electron peptide ions produced through various approaches including the capture of low-energy electrons, electron detachment, and electron transfer. C1 Univ Hong Kong, Dept Chem, Hong Kong, Hong Kong, Peoples R China. Pacific NW Natl Lab, Fundamental Sci Div, Richland, WA 99352 USA. RP Laskin, J (reprint author), Univ Hong Kong, Dept Chem, Hong Kong, Hong Kong, Peoples R China. EM Julia.Laskin@pnl.gov RI Chu, Ivan /D-3065-2009; Yang, Zhibo/E-4088-2010; Laskin, Julia/H-9974-2012 OI Laskin, Julia/0000-0002-4533-9644 NR 71 TC 77 Z9 77 U1 0 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD SEP 1 PY 2007 VL 79 IS 17 BP 6607 EP 6614 DI 10.1021/ac070777b PG 8 WC Chemistry, Analytical SC Chemistry GA 207HT UT WOS:000249242900030 PM 17676923 ER PT J AU Pau, S Whitten, WB Ramsey, JM AF Pau, S. Whitten, W. B. Ramsey, J. M. TI Planar geometry for trapping and separating ions and charged particles SO ANALYTICAL CHEMISTRY LA English DT Article ID MASS-SPECTROMETRY; PAUL TRAP; DESIGN AB A planar quadrupole ion trap is proposed. We have demonstrated an extremely large operating range by trapping ions and particles with mass-to-charge ratio ranging from 10(2) to 10(9) at frequencies from 2.8 x 10(6) to 60 Hz at an operating pressure of 1.1 x 10(-4) to 760 Torr, respectively, using a trap radius of r(1) = 1 mm. We have also performed mass spectrometry with a resolution of 1.2 amu with mass-to-charge range from 50 to 150. Our geometry is simple enough to be integrated into existing integrated circuits and microelectromechanical system devices, opening up the possibility of many novel hybrid applications and experiments. C1 Univ Arizona, Tucson, AZ 85721 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ N Carolina, Chapel Hill, NC 27599 USA. RP Pau, S (reprint author), Univ Arizona, Tucson, AZ 85721 USA. EM spau@optics.arizona.edu NR 29 TC 10 Z9 11 U1 3 U2 17 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD SEP 1 PY 2007 VL 79 IS 17 BP 6857 EP 6861 DI 10.1021/ac0706269 PG 5 WC Chemistry, Analytical SC Chemistry GA 207HT UT WOS:000249242900064 PM 17672521 ER PT J AU Payne, DC Aranas, A Mcneil, MM Duderstadt, S Rose, CE AF Payne, Daniel C. Aranas, Aaron Mcneil, Michael M. Duderstadt, Susan Rose, Charles E., Jr. TI Concurrent vaccinations and US military hospitalizations SO ANNALS OF EPIDEMIOLOGY LA English DT Article DE multiple vaccinations; military hospitalizations; vaccine analytic unit ID MEDICAL SURVEILLANCE SYSTEM; GULF-WAR; MULTIPLE VACCINATIONS; ANTHRAX VACCINATION; ADVERSE REACTIONS; RISK-FACTORS; ILL HEALTH; VACCINES; VETERANS; FUTURE AB PURPOSE: To investigate whether concurrent vaccinations (>= 2 vaccinations on consecutive days) are associated with hospitalization risk among U.S. military personnel. METHODS: We analyzed Defense Medical Surveillance System data from January 1998 through December 2003 for 117,876 active component U.S. military personnel. We performed a time-to-event analysis of a historical cohort using a Cox proportional hazards model comparing hospitalizations during a 120-day postvaccination exposure interval to hospitalizations within a 120-day pre-exposure interval. We excluded personnel who were deployed during these intervals and those having hospitalizations 60 days prior to the concurrent vaccination exposure. Hazards ratios (HRs) with 95% confidence intervals were calculated, adjusting for demographic, occupational, health, and calendar variables. RESULTS: We analyzed 19,743 persons having concurrent vaccinations. Receiving two or more vaccinations concurrently was not statistically associated with the adjusted risk of hospitalization (HR = 0.90 [0-75, 1.09]). Furthermore, no statistically significant associations were detected for 3 concurrent vaccinations (HR = 0.86 [0,58, 1.28]), 4 concurrent vaccinations (HR = 1.08, [0.66, 1.74]), or five or more concurrent vaccinations (HR = 0.86 [0.49, 1.51]). CONCLUSIONS: No evidence was found that the concurrent receipt of multiple vaccinations is related to hospitalization risk among this sample of U.S. military personnel. (c) 2007 Elsevier Inc. All rights reserved. C1 Ctr Dis Control & Prevent, Bacterial Vaccine Preventable Dis Branch, Epidemiol & Surveillance Div, Natl Immunizat Program, Atlanta, GA USA. Oak Ridge Inst Sci & Educ, Oak Ridge, TN USA. RP Payne, DC (reprint author), CDC, 1600 Clifton Rd NE,MS-A47, Atlanta, GA 30333 USA. EM DVP6@CDC.GOV NR 27 TC 6 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1047-2797 J9 ANN EPIDEMIOL JI Ann. Epidemiol. PD SEP PY 2007 VL 17 IS 9 BP 697 EP 703 DI 10.1016/j.annepidem.2007.03.018 PG 7 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 208AV UT WOS:000249293100007 PM 17574864 ER PT J AU Beylkin, G Cramer, R Fann, G Harrison, RJ AF Beylkin, Gregory Cramer, Robert Fann, George Harrison, Robert J. TI Multiresolution separated representations of singular and weakly singular operators SO APPLIED AND COMPUTATIONAL HARMONIC ANALYSIS LA English DT Article DE separated representation; Poisson kernel; projector on the divergence free functions; multiwavelet bases; integral operators ID MULTIWAVELET BASES; QUANTUM-CHEMISTRY; EXPONENTIAL-SUMS; WAVE-FUNCTIONS; HARTREE-FOCK; APPROXIMATION; DIMENSIONS; ALGORITHMS; EQUATIONS AB For a finite but arbitrary precision, we construct efficient low separation rank representations for the Poisson kernel and for the projector on the divergence free functions in the dimension d = 3. Our construction requires computing only one-dimensional integrals. We use scaling functions of multiwavelet bases, thus making these representations available for a variety of multiresolution algorithms. Besides having many applications, these two operators serve as examples of weakly singular and singular operators for which our approach is applicable. Our approach provides a practical implementation of separated representations of a class of weakly singular and singular operators in dimensions d >= 2. (c) 2007 Elsevier Inc. All rights reserved. C1 Univ Colorado, Dept Appl Math, Boulder, CO 80309 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Beylkin, G (reprint author), Univ Colorado, Dept Appl Math, 526 UCB, Boulder, CO 80309 USA. EM beylkin@colorado.edu RI Beylkin, Gregory/G-6653-2011; OI BEYLKIN, GREGORY/0000-0003-3447-1460 NR 23 TC 14 Z9 14 U1 2 U2 3 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1063-5203 J9 APPL COMPUT HARMON A JI Appl. Comput. Harmon. Anal. PD SEP PY 2007 VL 23 IS 2 BP 235 EP 253 DI 10.1016/j.acha.2007.01.001 PG 19 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 208AW UT WOS:000249293200006 ER PT J AU Bender, KS Yen, HCB Hemme, CL Yang, Z He, Z He, Q Zhou, J Huang, KH Alm, EJ Hazen, TC Arkin, AP Wall, JD AF Bender, Kelly S. Yen, Huei-Che Bill Hemme, Christopher L. Yang, Zamin He, Zhili He, Qiang Zhou, Jizhong Huang, Katherine H. Alm, Eric J. Hazen, Terry C. Arkin, Adam P. Wall, Judy D. TI Analysis of a ferric uptake regulator (Fur) mutant of Desulfovibfio vulgatis hildenborough SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID IRON-RESPONSIVE REGULATION; HELICOBACTER-PYLORI; BACILLUS-SUBTILIS; VULGARIS HILDENBOROUGH; CAMPYLOBACTER-JEJUNI; OXIDATIVE STRESS; TRANSCRIPTIONAL RESPONSE; COORDINATE REGULATION; SUPEROXIDE-DISMUTASE; DEPENDENT TRANSPORT AB Previous experiments examining the transcriptional profile of the anaerobe Desulfovibrio vulgaris demonstrated up-regulation of the Fur regulon in response to various environmental stressors. To test the involvement of Fur in the growth response and transcriptional regulation of D. vulgaris, a targeted mutagenesis procedure was used for deleting the fur gene. Growth of the resulting Delta fur mutant (JW707) was not affected by iron availability, but the mutant did exhibit increased sensitivity to nitrite and osmotic stresses compared to the mild type. Transcriptional profiling of JW707 indicated that iron-bound Fur acts as a traditional repressor for ferrous iron uptake genes (feoAB) and other genes containing a predicted Fur binding site within their promoter. Despite the apparent lack of siderophore biosynthesis genes within the D. vulgaris genome, a large 12-gene operon encoding orthologs to TonB and TolQR also appeared to be repressed by iron-bound Fur. While other genes predicted to be involved in iron homeostasis were unaffected by the presence or absence of Fur, alternative expression patterns that could be interpreted as repression or activation by iron-free Fur were observed. Both the physiological and transcriptional data implicate a global regulatory role for Fur in the sulfate-reducing bacterium D. vulgaris. C1 Univ Missouri, Dept Biochem, Columbia, MO 65211 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Oklahoma, Dept Bot & Microbiol, Inst Environm Genom, Norman, OK 73019 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. MIT, Biol Engn Div, Cambridge, MA 02139 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Bioengn, Berkeley, CA 94720 USA. Howard Hughes Med Inst, Chevy Chase, MD 20815 USA. Temple Univ, Dept Civil & Environm Engn, Philadelphia, PA 19122 USA. RP Wall, JD (reprint author), Univ Missouri, Dept Biochem, 117 Schweitzer Hall, Columbia, MO 65211 USA. EM wallj@missouri.edu RI Arkin, Adam/A-6751-2008; He, Qiang/G-9061-2011; He, Zhili/C-2879-2012; Hazen, Terry/C-1076-2012; OI Arkin, Adam/0000-0002-4999-2931; He, Qiang/0000-0002-7155-6474; Hazen, Terry/0000-0002-2536-9993; Bender, Kelly/0000-0002-0025-2166 NR 75 TC 51 Z9 51 U1 2 U2 11 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD SEP PY 2007 VL 73 IS 17 BP 5389 EP 5400 DI 10.1128/AEM.00276-07 PG 12 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 207JF UT WOS:000249246700001 PM 17630305 ER PT J AU Lee, SK Chou, HH Pfleger, BF Newman, JD Yoshikuni, Y Keasling, JD AF Lee, Sung Kuk Chou, Howard H. Pfleger, Brian F. Newman, Jack D. Yoshikuni, Yasuo Keasling, Jay D. TI Directed evolution of AraC for improved compatibility of arabinose- and lactose-inducible promoters SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID HIGH-LEVEL EXPRESSION; ESCHERICHIA-COLI; TRANSCRIPTIONAL ACTIVATOR; PROTEIN EXPRESSION; GENE-EXPRESSION; BACTERIA; BINDING; NETWORKS; SYSTEM; CELLS AB Synthetic biological systems often require multiple, independently inducible promoters in order to control the expression levels of several genes; however, cross talk between the promoters limits this ability. Here, we demonstrate the directed evolution of AraC to construct an arabinose-inducible (P-BAD) system that is more compatible with IPTG (isopropyl-beta-D-1-thiogalactopyranoside) induction of a lactose-inducible (P-lac) system. The constructed system is 10 times more sensitive to arabinose and tolerates IPTG significantly better than the wild type. Detailed studies indicate that the AraC dimerization domain and C terminus are important for the increased sensitivity of AraC to arabinose. C1 Univ Calif Berkeley, Ctr Synthet Biol, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Bioengn, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Synthet Biol Dept, Phys Biosci Div, Berkeley, CA USA. RP Keasling, JD (reprint author), Univ Calif Berkeley, Ctr Synthet Biol, Dept Chem Engn, 717 Potter St,Bldg 977,Mail Code 3224, Berkeley, CA 94720 USA. EM keasling@berkeley.edu RI Lee, Sung/E-6525-2010; Keasling, Jay/J-9162-2012 OI Keasling, Jay/0000-0003-4170-6088 FU NIGMS NIH HHS [GM070763-01, R01 GM070763] NR 34 TC 53 Z9 54 U1 1 U2 8 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD SEP PY 2007 VL 73 IS 18 BP 5711 EP 5715 DI 10.1128/AEM.00791-07 PG 5 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 211VC UT WOS:000249550400002 PM 17644634 ER PT J AU Boukhalfa, H Icopini, GA Reilly, SD Neu, MP AF Boukhalfa, Hakim Icopini, Gary A. Reilly, Sean D. Neu, Mary P. TI Plutonium(IV) reduction by the metal-reducing bacteria Geobacter metallireducens GS15 and Shewanella oneidensis MR1 SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID CRYSTAL-STRUCTURE; DISSOLUTION; SIDEROPHORES; URANIUM; IRON; SOLUBILIZATION; ENVIRONMENT; SPECIATION; COMPLEXES; BINDING AB The bacterial reduction of actinides has been suggested as a possible remedial strategy for actinide-contaminated environments, and the bacterial reduction of Pu(VI/V) has the potential to produce highly insoluble Pu(M solid phases. However, the behavior of plutonium with regard to bacterial reduction is more complex than for other actinides because it is possible for Pu(IV) to be further reduced to Pu(III), which is relatively more soluble than Pu(W). This work investigates the ability of the metal-reducing bacteria Geobacter metallireducens GS15 and Shewanella oneidensis MR1 to enzymatically reduce freshly precipitated amorphous Pu(IV) (OH)(4) Pu(IV)(OH)(4(am)) and soluble Pu(IV)(EDTA). In cell suspensions without added complexing ligands, minor Pu(III) production was observed in cultures containing S. oneidensis, but little or no Pu(III) production was observed in cultures containing G. metallireducens. In the presence of EDTA, most of the Pu(IV)(OH)(4(am)) present was reduced to Pu(III) and remained soluble in cell suspensions of both S. oneidensis and G. metallireducens. When soluble Pu(IV)(EDTA) was provided as the terminal electron acceptor, cell suspensions of both S. oneidensis and G. metallireducens rapidly reduced Pu(IV)(EDTA) to Pu(III) (EDTA) with nearly complete reduction within 20 to 40 min, depending on the initial concentration. Neither bacterium was able to use Pu(IV) (in any of the forms used) as a terminal electron acceptor to support growth. These results have significant implications for the potential remediation of plutonium and suggest that strongly reducing environments where complexing ligands are present may produce soluble forms of reduced Pu species. C1 Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP Boukhalfa, H (reprint author), Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. EM hakim@lanl.gov NR 28 TC 35 Z9 36 U1 2 U2 27 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD SEP PY 2007 VL 73 IS 18 BP 5897 EP 5903 DI 10.1128/AEM.00747-07 PG 7 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 211VC UT WOS:000249550400024 PM 17644643 ER PT J AU Ledbetter, RN Connon, SA Neal, AL Dohnalkova, A Magnuson, TS AF Ledbetter, Rhesa N. Connon, Stephanie A. Neal, Andrew L. Dohnalkova, Alice Magnuson, Timothy S. TI Biogenic mineral production by a novel arsenic-metabolizing thermophilic bacterium from the Alvord Basin, oregon SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID SP. NOV; REDUCTION; OXIDATION; ANAEROBE AB The Alvord Basin in southeast Oregon contains a variety of hydrothermal features which have never been microbiologically characterized. A sampling of Murky Pot (61 degrees C; pH 7.1) led to the isolation of a novel arsenic-metabolizing organism (YeAs) which produces an arsenic sulfide mineral known as beta-realgar, a mineral that has not previously been observed as a product of bacterial arsenic metabolism. YeAs was grown on a freshwater medium and utilized a variety of organic substrates, particularly carbohydrates and organic acids. The temperature range for growth was 37 to 75 degrees C (optimum, 55 degrees C), and. the pH range for growth was 6.0 to 8.0 (optimum, pH 7.0 to 7.5). No growth was observed when YeAs was grown under aerobic conditions. The doubling time when the organism was grown with yeast extract and As(V) was 0.71 h. Microscopic examination revealed Gram stain-indeterminate, non-spore-forming, nonmotile, rod-shaped cells, with dimensions ranging from 0.1 to 0.2 mu m wide by 3 to 10 mu m long. Arsenic sulfide mineralization of cell walls and extracellular arsenic sulfide particulate deposition were observed with electron microscopy and elemental analysis. 16S rRNA gene analysis placed YeAs in the family Clostridiaceae and indicated that the organism is most closely related to the Caloramator and Thermobrachium species. The G + C content was 35%. YeAs showed no detectable respiratory arsenate reductase but did display significant detoxification arsenate reductase activity. The phylogenetic, physiological, and morphological characteristics of YeAs demonstrate that it is an anaerobic, moderately thermophilic, arsenic-reducing bacterium. This organism and its associated metabolism could have major implications in the search for innovative methods for arsenic waste management and in the search for novel biogenic mineral signatures. C1 Idaho State Univ, Dept Biol Sci, Pocatello, ID 83209 USA. Univ Georgia, Dept Crop & Soil Sci, Athens, GA 30602 USA. Univ Georgia, Savannah River Ecol Lab, Athens, GA 30602 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Magnuson, TS (reprint author), Idaho State Univ, Dept Biol Sci, POB 8007, Pocatello, ID 83209 USA. EM magntimo@isu.edu RI Neal, Andrew/C-7596-2011; Connon, Stephanie/K-1959-2012 NR 41 TC 16 Z9 17 U1 3 U2 22 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD SEP PY 2007 VL 73 IS 18 BP 5928 EP 5936 DI 10.1128/AEM.00371-07 PG 9 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 211VC UT WOS:000249550400028 PM 17630300 ER PT J AU Karim, K Klasson, KT Drescher, SR Ridenour, W Borole, AP Al-Dahhan, MH AF Karim, Khursheed Klasson, K. Thomas Drescher, Sadie R. Ridenour, Whitney Borole, Abhijeet P. Al-Dahhan, Muthanna H. TI Mesophilic digestion kinetics of manure slurry SO APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article DE anaerobic; digestion; kinetics; manure; mesophilic; mathematical model; methane production ID ANAEROBIC-DIGESTION; ANIMAL WASTE; METHANE; MODEL; POPULATION AB Anaerobic digestion kinetics study of cow manure was performed at 35 C in bench-scale gas-lift digesters (3.78 l working volume) at eight different volatile solids ( VS) loading rates in the range of 1.11 - 5.87 g l(-1) day(-1). The digesters produced methane at the rates of 0.44 - 1.181 l(-1) day(-1), and the methane content of the biogas was found to increase with longer hydraulic retention time (HRT). Based on the experimental observations, the ultimate methane yield and the specific methane productivity were estimated to be 0.42 l CH4 (g VS loaded)(-1) and 0.45 l CH4 (g VS consumed)(-1), respectively. Total and dissolved chemical oxygen demand (COD) consumptions were calculated to be 59 - 17% and 78 - 43% at 24.4 - 4.6 days HRTs, respectively. Maximum concentration of volatile fatty acids in the effluent was observed as 0.7 g l(-1) at 4.6 days HRT, while it was below detection limit at HRTs longer than 11 days. The observed methane production rate did not compare well with the predictions of Chen and Hashimoto's [1] and Hill's [2] models using their recommended kinetic parameters. However, under the studied experimental conditions, the predictions of Chen and Hashimoto's [1] model compared better to the observed data than that of Hill's [2] model. The nonlinear regression analysis of the experimental data was performed using a derived methane production rate model, for a completely mixed anaerobic digester, involving Contois kinetics [3] with endogenous decay. The best fit values for the maximum specific growth rate (mu m) and dimensionless kinetic parameter (K) were estimated as 0.43 day(-1) and 0.89, respectively. The experimental data were found to be within 95% confidence interval of the prediction of the derived methane production rate model with the sum of residual squared error as 0.02. C1 Washington Univ, Dept Environm & Chem Engn, Chem React Engn Lab, St Louis, MO 63130 USA. Univ Arkansas, Dept Chem Engn, Fayetteville, AR 72701 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. USDA ARS, So Reg Res Ctr, New Orleans, LA 70124 USA. Oak Ridge Inst Sci & Educ, ORAU, Oak Ridge, TN 37830 USA. RP Karim, K (reprint author), Washington Univ, Dept Environm & Chem Engn, Chem React Engn Lab, St Louis, MO 63130 USA. EM kkarim@uark.edu RI Borole, AP/F-3933-2011; OI Klasson, K. Thomas/0000-0003-3358-3081; Borole, Abhijeet/0000-0001-8423-811X NR 15 TC 14 Z9 14 U1 5 U2 20 PU HUMANA PRESS INC PI TOTOWA PA 999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA SN 0273-2289 J9 APPL BIOCHEM BIOTECH JI Appl. Biochem. Biotechnol. PD SEP PY 2007 VL 142 IS 3 BP 231 EP 242 DI 10.1007/s12010-007-0025-4 PG 12 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 219FM UT WOS:000250070100002 PM 18025584 ER PT J AU Pierce, EM McGrail, BP Martin, PF Marra, J Arey, BW Geiszler, KN AF Pierce, Eric M. McGrail, B. P. Martin, P. F. Marra, J. Arey, B. W. Geiszler, K. N. TI Accelerated weathering of high-level and plutonium-bearing lanthanide borosilicate waste glasses under hydraulically unsaturated conditions SO APPLIED GEOCHEMISTRY LA English DT Article ID THERMODYNAMIC MODEL; DISSOLUTION RATES; IMMOBILIZATION; SOLUBILITY; PUO2(AM); SYSTEM AB The US Department of Energy (DOE) has proposed that a can-in-canister waste package design be used for disposal of excess weapons-grade Pu at the proposed mined geologic repository at Yucca Mountain, Nevada. This configuration consists of a high-level waste (HLW) canister fitted with a rack that holds mini-canisters containing a Pu-bearing lanthanide borosilicate (LaBS) waste glass and/or titanate-based ceramic (similar to 15% of the total canister volume). The remaining volume of the HLW canister is then filled with HLW glass (similar to 85% of the total canister volume). A 6-a pressurized unsaturated flow (PUF) test was conducted to investigate waste form-waste form interactions that may occur when water penetrates the canisters and contacts the waste forms. The PUF column volumetric water content was observed to increase steadily during the test because of water accumulation associated with alteration phases formed on the surfaces of the glasses. Periodic excursions in effluent pH, electrical conductivity, and solution chemistry were monitored and correlated with the formation of a clay phase(s) during the test. Geochemical modeling, with the EQ3NR code, of select effluent solution samples suggests the dominant secondary reaction product for the surrogate HLW glass, SRL-202, is a smectite di-octahedral clay phase(s), possibly nontronite [Na-0.33 Fe-2(Alsi)(4)O-10(OH)(2)center dot n(H2O)] or beidellite [Na0.33Al2.33Si3.67O10(OH)(2)]. This clay phase was identified in scanning electron microscope (SEM) images as discrete spherical particles growing out of a hydrated gel layer on reacted SRL-202 glass. Alpha energy analysis (AEA) of aliquots of select effluent samples that were filtered through a 1.8 nm filter suggest that approximately 80% of the total measurable Pu was in the form of a filterable particulate, in comparison to unfiltered aliquots of the same sample. These results suggest the filterable particles are >1.8 nm but smaller than the 0.2 mu m average diameter openings of the Ti porous plate situated at the base of the column. In this advection-dominated system, Pu appeared to be migrating principally as or in association with colloids after being released from the LaBS glass. Analyses of reacted LaBS glass particles with SEM with energy dispersive X-ray spectroscopy suggest that Pu may have segregated into a discrete disk-like phase, possibly PuO2. Alteration products that contain the neutron absorber Gd have not been positively identified. Separation of the Pu and the neutron absorber Gd during glass dissolution and transport could be a criticality issue for the proposed repository. However, the translation and interpretation of these long-term PUF test results to actual disposed waste packages requires further analysis. (C) 2007 Elsevier Ltd. All rights reserved. C1 Pacific NW Natl Lab, Environm Technol Directorate, Richland, WA 99352 USA. Westinghouse Savannah River Co, Savannah River Lab, Aiken, SC 29808 USA. RP Pierce, EM (reprint author), Pacific NW Natl Lab, Environm Technol Directorate, PO Box 999,MS K6-81, Richland, WA 99352 USA. EM Eric.Pierce@pnl.gov RI Pierce, Eric/G-1615-2011 OI Pierce, Eric/0000-0002-4951-1931 NR 46 TC 28 Z9 30 U1 1 U2 20 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0883-2927 J9 APPL GEOCHEM JI Appl. Geochem. PD SEP PY 2007 VL 22 IS 9 BP 1841 EP 1859 DI 10.1016/j.apgeochem.2007.03.056 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 216VH UT WOS:000249906600001 ER PT J AU Slowey, AJ Johnson, SB Newville, M Brown, GE AF Slowey, Aaron J. Johnson, Stephen B. Newville, Matthew Brown, Gordon E., Jr. TI Speciation and colloid transport of arsenic from mine tailings SO APPLIED GEOCHEMISTRY LA English DT Article ID RAY-ABSORPTION SPECTROSCOPY; ORGANIC-ACIDS; EXAFS SPECTROSCOPY; CHEMICAL EXTRACTIONS; MERCURY SPECIATION; CONTAMINATED SOILS; SYNTHETIC JAROSITE; FINE-STRUCTURE; IRON-OXIDE; SEDIMENTS AB In addition to affecting biogeochemical transformations, the speciation of As also influences its transport from tailings at inoperative mines. The speciation of As in tailings from the Sulfur Bank Mercury Mine site in Clear Lake, California (USA) (a hot-spring Hg deposit) and particles mobilized from these tailings have. been examined during laboratory-column experiments. Solutions containing two common, plant-derived organic acids (oxalic and citric acid) were pumped at 13 pore volumes d(-1) through 25 by 500 mm columns of calcined Hg ore, analogous to the pedogenesis of tailings. Chemical analysis of column effluent indicated that all of the As mobilized was particulate (1.5 mg, or 6% of the total As in the column through 255 pore volumes of leaching). Arsenic speciation was evaluated using X-ray absorption spectroscopy (XAS), indicating the dominance of arsenate [As(V)] sorbed to poorly crystalline Fe(III)-(hydr)oxides and coprecipitated with jarosite [KFe3(SO4, ASO(4))(2)(OH)(6)] with no detectable primary or secondary minerals in the tailings and mobilized particles. Sequential chemical extractions (SCE) of <45 mu m mine tailings fractions also suggest that As occurs adsorbed to Fe (hydr)oxides (35%) and coprecipitated within poorly crystalline phases (45%). In addition, SCEs suggest that As is associated with 1 N acid-soluble phases such as carbonate minerals (20%) and within crystalline Fe-(hydr)oxides (10%). The finding that As is transported from these mine tailings dominantly as As(V) adsorbed to Fe (hydr)oxides or coprecipitated within hydroxysulfates such as jarosite suggests that As release from soils and sediments contaminated with tailings will be controlled by either organic acid-promoted dissolution or reductive dissolution of host phases. (C) 2007 Elsevier Ltd. All rights reserved. C1 Stanford Univ, Dept Geog & Environm Sci, Surface & Aqueous Geochem Grp, Stanford, CA 94305 USA. Univ Chicago, Consortium Adv Radiat Sources, Chicago, IL 60637 USA. Stanford Synchrotron Radiat Lab, SLAC, Menlo Pk, CA 94025 USA. RP Slowey, AJ (reprint author), US Geol Survey, 345 Middlefield Rd,MS 901, Menlo Pk, CA 94025 USA. EM aaron.slowey@gmail.com NR 70 TC 43 Z9 44 U1 3 U2 37 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0883-2927 J9 APPL GEOCHEM JI Appl. Geochem. PD SEP PY 2007 VL 22 IS 9 BP 1884 EP 1898 DI 10.1016/j.apgeochem.2007.03.053 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 216VH UT WOS:000249906600004 ER PT J AU Qafoku, NP Qafoku, O Ainsworth, CC Dohnalkova, A McKinley, SG AF Qafoku, Nikolla P. Qafoku, Odeta Ainsworth, Calvin C. Dohnalkova, Alice McKinley, Susan G. TI Fe-solid phase transformations under highly basic conditions SO APPLIED GEOCHEMISTRY LA English DT Article ID SIMULATED TANK WASTE; HYPERALKALINE CONDITIONS; NITRATE-CANCRINITE; CR(VI) REDUCTION; HANFORD SITE; DISSOLUTION; SEDIMENTS; PRECIPITATION; ALKALINE; PH AB Hyperalkaline and saline radioactive waste fluids with elevated temperatures from S-SX high-level waste tank farm at Hanford, WA, USA accidentally leaked into sediments beneath the tanks, initiating a series of geochemical processes and reactions whose significance and extent was unknown. Among the most important processes was the dissolution of soil minerals and precipitation of stable secondary phases. The objective of this investigation was to study the release of Fe into the aqueous phase upon dissolution of Fe-bearing soil minerals, and the subsequent formation of Fe-rich precipitates. Batch reactors were used to conduct experiments at 50 degrees C using solutions similar in composition to the waste fluids. Results clearly showed that, similarly to Si and Al, Fe was released from the dissolution of soil minerals (most likely phyllosilicates such as biotite, smectite and chlorite). The extent of Fe release increased with base concentration and decreased with A1 concentration in the contacting solution. The maximum apparent rate of Fe release (0.566 x 10(-13) mol m(-2) s(-1)) was measured in the treatment with no A1 and a concentration of 4.32 mol L-1 NaOH in the contact solution. Results from electron microscopy indicated that while Si and A1 precipitated together to form feldspathoids in the groups of cancrinite and/or socialite, Fe precipitation followed a different pathway leading to the formation of hematite and goethite. The newly formed Fe oxy-hydroxides may increase the sorption capacity of the sediments, promote surface mediated reactions such as precipitation and heterogeneous redox reactions, and affect the phase distribution of contaminants and radionuclides. (C) 2007 Elsevier Ltd. All rights reserved. C1 Pacific NW Natl Lab, Environm Dynam & Simulat Grp, Richland, WA 99352 USA. RP Qafoku, NP (reprint author), Pacific NW Natl Lab, Environm Dynam & Simulat Grp, 902 Battelle Blvd,PO Box 999, Richland, WA 99352 USA. EM nik.qafoku@pnl.gov OI Qafoku, Nikolla P./0000-0002-3258-5379 NR 30 TC 5 Z9 5 U1 1 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0883-2927 J9 APPL GEOCHEM JI Appl. Geochem. PD SEP PY 2007 VL 22 IS 9 BP 2054 EP 2064 DI 10.1016/j.apgeochem.2007.04.023 PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 216VH UT WOS:000249906600015 ER PT J AU Nam, YS Jeon, S Shir, DJL Hamza, A Rogers, JA AF Nam, Yun-Suk Jeon, Seokwoo Shir, Daniel Jay-Lee Hamza, Alex Rogers, John A. TI Thick, three-dimensional nanoporous density-graded materials formed by optical exposures of photopolymers with controlled levels of absorption SO APPLIED OPTICS LA English DT Article ID SOFT LITHOGRAPHY; FGM AB Three-dimensional (3D) intensity distributions generated by light passing through conformal phase masks can be modulated by the absorption property of photosensitive materials. The intensity distributions have extremely long depth of focus, which is proportional to the size of the phase masks, and this enables one to pattern thick (similar to 100 mu m), nanoporous structures with precise control of grade density. Various density-graded 3D structures that result from computational modeling are demonstrated. Results of x-ray radiograph and the controlled absorption coefficient prove the dominant mechanism of the generated graded density is absorption of the photosensitive materials. The graded-density structures can be applied to a chemical reservoir for controlled release of chemicals and laser target reservoirs useful to shape shockless wave compression. (c) 2007 Optical Society of America. C1 Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Frederick Seitz Mat Res Lab, Urbana, IL 61801 USA. RP Rogers, JA (reprint author), Univ Illinois, Dept Mat Sci & Engn, 1304 Green St, Urbana, IL 61801 USA. EM jrogers@uiuc.edu RI JEON, SEOKWOO/C-1701-2011; Rogers, John /L-2798-2016 NR 13 TC 9 Z9 11 U1 1 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD SEP 1 PY 2007 VL 46 IS 25 BP 6350 EP 6354 DI 10.1364/AO.46.006350 PG 5 WC Optics SC Optics GA 221ZP UT WOS:000250266200021 PM 17805373 ER PT J AU Lucarelli, A Frey, A Yang, R Lupke, G Grilli, F Haugan, T Levin, G Barnes, P AF Lucarelli, A. Frey, A. Yang, R. Luepke, G. Grilli, F. Haugan, T. Levin, G. Barnes, P. TI AC current driven dynamic vortex state in YBa2Cu3O7-x SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article ID INDUCED ORGANIZATION; SUPERCONDUCTORS; FILMS; BI2SR2CACU2O8; CRYSTALS; LATTICE; MOTION; MEMORY; PHASES; MATTER AB Time-resolved magneto-optical imaging measurements show that an ac current enables the vortex matter in YBa2Cu3O7-x thin films to reorganize into two coexisting steady states of driven vortex motion with different characteristics: a quasi-static disordered glassy state in the sample interior and a dynamic state of plastic motion near the edges. Finite-element calculations consistent with the critical state model show good agreement with the measured field profiles in the quasi-static state but predict a larger hysteretic behavior in the dynamic state. C1 Coll William & Mary, Dept Appl Sci, Williamsburg, VA 23187 USA. Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. Wright Patterson AFB, AF Res Lab, Wright Patterson AFB, OH 45433 USA. RP Lucarelli, A (reprint author), Coll William & Mary, Dept Appl Sci, Williamsburg, VA 23187 USA. EM axluca@wm.edu RI Lucarelli, Andrea/A-5411-2010 NR 25 TC 3 Z9 3 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD SEP PY 2007 VL 88 IS 4 BP 601 EP 604 DI 10.1007/s00339-007-4018-5 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 190MW UT WOS:000248064100002 ER PT J AU Spahn, I Steyn, GF Nortier, FM Coenen, HH Qaim, SM AF Spahn, I. Steyn, G. F. Nortier, F. M. Coenen, H. H. Qaim, S. M. TI Excitation functions of Ge-nat(p,xn)(71,72,73,74) As reactions up to 100 MeV with a focus on the production of As-72 for medical and As-73 for environmental studies SO APPLIED RADIATION AND ISOTOPES LA English DT Article DE As-71; (72)AS; (73)AS; As-74; excitation function; integral yield; model calculation AB Excitation functions for the formation of the arsenic radionuclides 71As, As-72, As-73 and As-74 in the interaction of protons with Ge-nat were measured from the respective threshold energy up to 100 MeV. The conventional stacked-foil technique was used and the needed thin samples were prepared by sedimentation. Irradiations were done at three cyclotrons: CV 28 and injector of COSY at Forschungszentrum Julich, and Separate Sector Cyclotron at iThemba LABS, Somerset West. The radioactivity was measured via high-resolution gamma-ray spectrometry. The measured cross section data were compared with the literature data as well as with the nuclear model calculations. In both cases, the results generally agree but there are discrepancies in some areas, the results of nuclear model calculation and some of the literature data being somewhat higher than our data. The integral yields of the four radionuclides were calculated from the measured excitation functions. The beta(+) emitting nuclide As-72 (T-1/2 = 26.01 h) can be produced with reasonable radionuclidic purity (As-71 impurity: < 10%) over the energy range E-p = 18 -> 8 MeV; the yield of 93 MBq/mu A h is, however, low. The radionuclide As-73 (T-1/2 = 80.30 d), a potentially useful indicator in environmental studies, could be produced with good radionuclidic purity (As-74 impurity: < 11%) over the energy range E-p = 30 -> 18 MeV, provided, a decay time of about 60 days is allowed. Its yield would then correspond to 2.4 MBq/mu A h, and GBq amounts could be produced when using a high current target. (C) 2007 Elsevier Ltd. All rights reserved. C1 Forschungszentrum Julich, Inst Nukl Chem, D-52425 Julich, Germany. Univ Cologne, D-50674 Cologne, Germany. iThemba LABS, Radionuclide Prod, ZA-7129 Somerset West, South Africa. Los Alamos Natl Lab, Isotopes & Nucl Chem Grp, Los Alamos, NM USA. RP Qaim, SM (reprint author), Forschungszentrum Julich, Inst Nukl Chem, D-52425 Julich, Germany. EM s.m.qaim@fz-juelich.de RI Coenen, Heinz/K-3078-2013 OI Coenen, Heinz/0000-0002-3810-103X NR 21 TC 22 Z9 22 U1 0 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD SEP PY 2007 VL 65 IS 9 BP 1057 EP 1064 DI 10.1016/j.apradiso.2007.04.012 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 211SB UT WOS:000249542500010 PM 17574855 ER PT J AU Di Costanzo, L Moulin, M Haertlein, M Meilleur, F Christianson, DW AF Di Costanzo, Luigi Moulin, Martine Haertlein, Michael Meilleur, Flora Christianson, David W. TI Expression, purification, assay, and crystal structure of perdeuterated human arginase I SO ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS LA English DT Article ID BINUCLEAR MANGANESE CLUSTER; FEMALE SEXUAL AROUSAL; PHYSIOLOGICAL-ROLE; HISTONE DEACETYLASE; ERECTILE FUNCTION; PROTEIN MODELS; HUMAN HDAC8; CRYSTALLOGRAPHY; INHIBITORS; SUPERFAMILY AB Arginase is a manganese metalloenzyme that catalyzes the hydrolysis of L-arginine to yield L-ornithine and urea. In order to establish a foundation for future neutron diffraction studies that will provide conclusive structural information regarding proton/deuteron positions in enzyme-inhibitor complexes, we have expressed, purified, assayed, and determined the X-ray crystal structure of perdeuterated (i.e., fully deuterated) human arginase I complexed with 2(S)-amino-6-boronohexanoic acid (ABH) at 1.90 A resolution. Prior to the neutron diffraction experiment, it is important to establish that perdeuteration does not cause any unanticipated structural or functional changes. Accordingly, we find that perdeuterated human arginase I exhibits catalytic activity essentially identical to that of the unlabeled enzyme. Additionally, the structure of the perdeuterated human arginase I-ABH complex is identical to that of the corresponding complex with the unlabeled enzyme. Therefore, we conclude that crystals of the perdeuterated human arginase I-ABH complex are suitable for neutron crystallographic study. (c) 2007 Elsevier Inc. All rights reserved. C1 Univ Penn, Dept Chem, Roy & Diana Vagelos Lab, Philadelphia, PA 19104 USA. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. N Carolina State Univ, Dept Mol & Struct Biochem, Raleigh, NC 27695 USA. Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37831 USA. RP Christianson, DW (reprint author), Univ Penn, Dept Chem, Roy & Diana Vagelos Lab, Philadelphia, PA 19104 USA. EM chris@sas.upenn.edu OI Di Costanzo, Luigi/0000-0002-4795-2573 FU NIGMS NIH HHS [R01 GM049758, R01 GM049758-13] NR 37 TC 24 Z9 25 U1 4 U2 16 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0003-9861 J9 ARCH BIOCHEM BIOPHYS JI Arch. Biochem. Biophys. PD SEP 1 PY 2007 VL 465 IS 1 BP 82 EP 89 DI 10.1016/j.abb.2007.04.036 PG 8 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 206IF UT WOS:000249176400010 PM 17562323 ER PT J AU Fellermann, H Rasmussen, S Ziock, HJ Sole, RV AF Fellermann, Harold Rasmussen, Steen Ziock, Hans-Joachim Sole, Ricard V. TI Life cycle of a minimal protocell - A dissipative particle dynamics study SO ARTIFICIAL LIFE LA English DT Article DE artificial life; minimal protocell; self-assembly; chemical reactions; dissipative particle dynamics ID MESOSCOPIC SIMULATION; VESICLES; CELL; AGGREGATION; SURFACTANTS; MORPHOLOGY; MICELLES; MODELS AB Cross-reactions and other systernatic difficulties generated by the coupling of functional chemical subsystems pose the largest challenge for assembling a viable protocell in the laboratory. Our Current work seeks to identify and clarify such key issues as we represent and analyze in Simulation 2 full implementation of a minimal protocell. Using a 3D dissipative particle dynamics simulation method, we are able to address the coupled diffusion, self-assembly, and chemical reaction processes required to model a full life cycle of a protocell composed of coupled genetic, metabolic, and container subsystems. Utilizing this minimal structural and functional representation of the constituent molecules, their interactions, and their reactions, we identify and explore the nature of the many linked processes for the full protoceflular system. Obviously the Simplicity of this simulation method combined with the inherent system complexity prevents us from expecting quantitative simulation predictions from these investigations. However, we report important findings on systemic processes, some previously predicted and some newly discovered, as we couple the protocellular self-assembly processes and chemical reactions. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Pompeu Fabra GRIB, ICREA Complex Syst Lab, Barcelona 08003, Spain. Santa Fe Inst, Santa Fe, NM 87501 USA. RP Fellermann, H (reprint author), Los Alamos Natl Lab, EES 6 MS D462, Los Alamos, NM 87545 USA. EM harold.fellermann@upf.edu; steen@lanl.gov; ziock@lanl.gov; ricard.sole@upf.edu RI Sole, Ricard/I-3379-2015 NR 34 TC 25 Z9 25 U1 0 U2 4 PU M I T PRESS PI CAMBRIDGE PA 238 MAIN STREET, STE 500, CAMBRIDGE, MA 02142-1046 USA SN 1064-5462 J9 ARTIF LIFE JI Artif. Life PD FAL PY 2007 VL 13 IS 4 BP 319 EP 345 DI 10.1162/artl.2007.13.4.319 PG 27 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA 207ZJ UT WOS:000249289300001 PM 17716015 ER PT J AU Roth, K Dieckmann, J Zogg, R Brodrick, J AF Roth, Kurt Dieckmann, John Zogg, Robert Brodrick, James TI Chilled beam cooling SO ASHRAE JOURNAL LA English DT Article C1 TIAX LLC, Cambridge, MA USA. US DOE, Bldg Technol Program, Washington, DC USA. RP Roth, K (reprint author), TIAX LLC, Cambridge, MA USA. NR 6 TC 9 Z9 9 U1 3 U2 9 PU AMER SOC HEATING REFRIGERATING AIR-CONDITIONING ENG, INC, PI ATLANTA PA 1791 TULLIE CIRCLE NE, ATLANTA, GA 30329 USA SN 0001-2491 J9 ASHRAE J JI ASHRAE J. PD SEP PY 2007 VL 49 IS 9 BP 84 EP + PG 2 WC Thermodynamics; Construction & Building Technology; Engineering, Mechanical SC Thermodynamics; Construction & Building Technology; Engineering GA 220AW UT WOS:000250130300013 ER PT J AU Ivezic, Z Smith, JA Miknaitis, G Lin, H Tucker, D Lupton, RH Gunn, JE Knapp, GR Strauss, MA Sesar, B Doi, M Tanaka, M Fukugita, M Holtzman, J Kent, S Yanny, B Schlegel, D Finkbeiner, D Padmanabhan, N Rockosi, CM Mario, J Bond, N Lee, B Stoughton, C Jester, S Harris, H Harding, P Morrison, H Brinkmann, J Schneider, DP York, D AF Ivezic, Zeljko Smith, J. Allyn Miknaitis, Gajus Lin, Huan Tucker, Douglas Lupton, Robert H. Gunn, James E. Knapp, Gillian R. Strauss, Michael A. Sesar, Branimir Doi, Mamoru Tanaka, Masayuki Fukugita, Masataka Holtzman, Jon Kent, Steve Yanny, Brian Schlegel, David Finkbeiner, Douglas Padmanabhan, Nikhil Rockosi, Constance M. Mario, Juric Bond, Nicholas Lee, Brian Stoughton, Chris Jester, Sebastian Harris, Hugh Harding, Paul Morrison, Heather Brinkmann, Jon Schneider, Donald P. York, Donald TI Sloan digital sky survey standard star catalog for stripe 82: The dawn of industrial 1% optical photometry SO ASTRONOMICAL JOURNAL LA English DT Article DE catalogs; instrumentation : photometers; methods : data analysis; standards; surveys; techniques : photometric ID SYNOPTIC SURVEY TELESCOPE; WHITE-DWARFS; DATA RELEASE; HOMOGENEOUS PHOTOMETRY; MODEL ATMOSPHERES; CELESTIAL EQUATOR; SELECTION; SYSTEM; CALIBRATION; GALAXIES AB We describe a standard star catalog constructed using multiple SDSS photometric observations ( at least four per band, with a median of 10) in the ugriz system. The catalog includes 1.01 million nonvariable unresolved objects from the equatorial stripe 82 (vertical bar delta(J2000.0)vertical bar < 1.266 degrees) in the right ascension range 20(h)34(m)-4(h)00(m) and with the corresponding r-band ( approximately Johnson V-band) magnitudes in the range 14-22. The distributions of measurements for individual sources demonstrate that the photometric pipeline correctly estimates random photometric errors, which are below 0.01 mag for stars brighter than 19.5, 20.5, 20.5, 20, and 18.5 in ugriz, respectively ( about twice as good as for individual SDSS runs). Several independent tests of the internal consistency suggest that the spatial variation of photometric zero points is not larger than similar to 0.01 mag (rms). In addition to being the largest available data set with optical photometry internally consistent at the similar to 1% level, this catalog provides a practical definition of the SDSS photometric system. Using this catalog, we show that photometric zero points for SDSS observing runs can be calibrated within a nominal uncertainty of 2% even for data obtained through 1 mag thick clouds, and we demonstrate the existence of He and H white dwarf sequences using photometric data alone. Based on the properties of this catalog, we conclude that upcoming large-scale optical surveys such as the Large Synoptic Survey Telescope will be capable of delivering robust 1% photometry for billions of sources. C1 Univ Washington, Dept Astron, Seattle, WA 98195 USA. Austin Peay State Univ, Dept Phys & Astron, Clarksville, TN 37044 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Tokyo, Inst Astron, Mitaka, Tokyo 1810015, Japan. Univ Tokyo, Grad Sch Sci, Dept Astron, Bunkyo Ku, Tokyo 1130033, Japan. Univ Tokyo, Inst Cosm Ray Res, Kashiwa, Chiba, Japan. New Mexico State Univ, Las Cruces, NM 88003 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95060 USA. Inst Adv Study, Princeton, NJ 08540 USA. Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England. US Naval Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. Case Western Reserve Univ, Dept Astron, Cleveland, OH 44106 USA. Apache Point Observ, Sunspot, NM 88349 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. RP Ivezic, Z (reprint author), Univ Washington, Dept Astron, Box 351580, Seattle, WA 98195 USA. RI Padmanabhan, Nikhil/A-2094-2012; OI Tucker, Douglas/0000-0001-7211-5729 NR 53 TC 188 Z9 188 U1 0 U2 5 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD SEP PY 2007 VL 134 IS 3 BP 973 EP 998 DI 10.1086/519976 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 204QD UT WOS:000249058200007 ER PT J AU Ave, M Bohacova, M Buonomo, B Busca, N Cazon, L Chemerisov, SD Conde, ME Crowell, RA Di Carlo, P Di Giulio, C Doubrava, M Esposito, A Facal, P Franchini, FJ Horandel, J Hrabovsky, M Iarlori, M Kasprzyk, TE Keilhauer, B Klages, H Kleifges, M Kuhlmann, S Mazzitelli, G Nozka, L Obermeier, A Palatka, M Petrera, S Privitera, P Ridky, J Rizi, V Rodriguez, G Salamida, F Schovanek, P Spinka, H Strazzeri, E Ulrich, A Yusof, ZM Vacek, V Valente, P Verzi, V Waldenmaier, T AF Ave, M. Bohacova, M. Buonomo, B. Busca, N. Cazon, L. Chemerisov, S. D. Conde, M. E. Crowell, R. A. Di Carlo, P. Di Giulio, C. Doubrava, M. Esposito, A. Facal, P. Franchini, F. J. Hoerandel, J. Hrabovsky, M. Iarlori, M. Kasprzyk, T. E. Keilhauer, B. Klages, H. Kleifges, M. Kuhlmann, S. Mazzitelli, G. Nozka, L. Obermeier, A. Palatka, M. Petrera, S. Privitera, P. Ridky, J. Rizi, V. Rodriguez, G. Salamida, F. Schovanek, P. Spinka, H. Strazzeri, E. Ulrich, A. Yusof, Z. M. Vacek, V. Valente, P. Verzi, V. Waldenmaier, T. CA AIRFLY Collaborat TI Measurement of the pressure dependence of emission induced by electrons SO ASTROPARTICLE PHYSICS LA English DT Article DE air fluorescence detection; ultra high energy cosmic rays; nitrogen collisional quenching ID AIR FLUORESCENCE; COLLISIONAL DEACTIVATION; SECONDARY ELECTRONS; MOLECULAR NITROGEN; IMPACT EXCITATION; PHOTON YIELDS; COSMIC-RAYS; DETECTOR; BEAM; SIMULATION AB The fluorescence detection of ultra high energy (>= 10(18) eV) cosmic rays requires a detailed knowledge of the fluorescence light emission from nitrogen molecules, which are excited by the cosmic ray shower particles along their path in the atmosphere. We have made a precise measurement of the fluorescence light spectrum excited by MeV electrons in dry air. We measured the relative intensities of 34 fluorescence bands in the wavelength range from 284 to 429 nm with a high resolution spectrograph. The pressure dependence of the fluorescence spectrum was also measured from a few hPa up to atmospheric pressure. Relative intensities and collisional quenching reference pressures for bands due to transitions from a common upper level were found in agreement with theoretical expectations. The presence of argon in air was found to have a negligible effect on the fluorescence yield. We estimated that the systematic uncertainty on the cosmic ray shower energy due to the pressure dependence of the fluorescence spectrum is reduced to a level of 1% by the AIRFLY results presented in this paper. (C) 2007 Elsevier B.V. All rights reserved. C1 Univ Roma Tor Vergata, Dipartimento Fis, I-00133 Rome, Italy. Sez INFN, I-00133 Rome, Italy. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Acad Sci Czech Republic, Inst Phys, CZ-18221 Prague 8, Czech Republic. Ist Nazl Fis Nucl, Lab Nazl Frascati, Sez Frascati, I-00044 Frascati, Italy. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Aquila, Dipartimento Fis, I-67010 Coppito, Italy. Ist Nazl Fis Nucl, I-67010 Coppito, Italy. Czech Tech Univ Prague, Prague 16607 6, Czech Republic. Dept Fis Particulas, E-15782 Santiago De Compostela, Spain. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Forschungszentrum Karlsruhe, Inst Kernphys, D-76021 Karlsruhe, Germany. Forschungszentrum Karlsruhe, Inst Prozessdatenverarbeitung & Elekt, D-76021 Karlsruhe, Germany. Tech Univ Munich, Phys Dept E12, D-85748 Garching, Germany. Ist Nazl Fis Nucl, Sez Roma 1, I-00185 Rome, Italy. RP Privitera, P (reprint author), Univ Roma Tor Vergata, Dipartimento Fis, Via Ric Sci, I-00133 Rome, Italy. EM priviter@roma2.infn.it RI valente, paolo/A-6640-2010; Buonomo, Bruno/F-6186-2010; Verzi, Valerio/B-1149-2012; Bohacova, Martina/G-5898-2014; Nozka, Libor/G-5550-2014; Cazon, Lorenzo/G-6921-2014; Schovanek, Petr/G-7117-2014; Ridky, Jan/H-6184-2014; Di Giulio, Claudio/B-3319-2015; Di Carlo, Piero/C-1657-2016; Di Carlo, Piero/Q-4450-2016; Rodriguez Fernandez, Gonzalo/C-1432-2014; OI Petrera, Sergio/0000-0002-6029-1255; Rizi, Vincenzo/0000-0002-5277-6527; Horandel, Jorg/0000-0001-6604-547X; valente, paolo/0000-0002-5413-0068; Buonomo, Bruno/0000-0002-3612-7308; Cazon, Lorenzo/0000-0001-6748-8395; Ridky, Jan/0000-0001-6697-1393; Di Giulio, Claudio/0000-0002-0597-4547; Di Carlo, Piero/0000-0003-4971-4509; Di Carlo, Piero/0000-0003-4971-4509; Rodriguez Fernandez, Gonzalo/0000-0002-4683-230X; Salamida, Francesco/0000-0002-9306-8447 NR 33 TC 66 Z9 66 U1 0 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-6505 J9 ASTROPART PHYS JI Astropart Phys. PD SEP PY 2007 VL 28 IS 1 BP 41 EP 57 DI 10.1016/j.astropartphys.2007.04.006 PG 17 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 223FO UT WOS:000250355200004 ER PT J AU Abdo, AA Allen, BT Berley, D Blaufuss, E Casanova, S Dingus, BL Ellsworth, RW Gonzalez, MM Goodman, JA Hays, E Hoffman, CM Kolterman, BE Lansdell, CP Linnemann, JT McEnery, JE Mincer, AI Nemethy, P Noyes, D Ryan, JM Samuelson, FW Parkinson, PMS Shoup, A Sinnis, G Smith, AJ Sullivan, GW Vasileiou, V Walker, GP Williams, DA Xu, XW Yodh, GB AF Abdo, A. A. Allen, B. T. Berley, D. Blaufuss, E. Casanova, S. Dingus, B. L. Ellsworth, R. W. Gonzalez, M. M. Goodman, J. A. Hays, E. Hoffman, C. M. Kolterman, B. E. Lansdell, C. P. Linnemann, J. T. McEnery, J. E. Mincer, A. I. Nemethy, P. Noyes, D. Ryan, J. M. Samuelson, F. W. Parkinson, P. M. Saz Shoup, A. Sinnis, G. Smith, A. J. Sullivan, G. W. Vasileiou, V. Walker, G. P. Williams, D. A. Xu, X. W. Yodh, G. B. TI Milagro constraints on very high energy emission from short-duration gamma-ray bursts SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; gamma rays : observations ID GRB 970417A; HOST GALAXY; TEV; AFTERGLOW; DISCOVERY; GRB-050709; TELESCOPE; SEARCH; FLARES; ARRAY AB Recent rapid localizations of short, hard gamma-ray bursts (GRBs) by the Swift and HETE satellites have led to the observation of the first afterglows and the measurement of the first redshifts from this type of burst ( Fox et al. 2005; Gehrels et al. 2005; Villasenor et al. 2005; Berger et al. 2005; Barthelmy et al. 2005). Detection of > 100 GeV counterparts would place powerful constraints on GRB mechanisms. Seventeen short-duration (< 5 s) GRBs detected by satellites occurred within the field of view of the Milagro gamma-ray observatory between 2000 January and 2006 December. We have searched the Milagro data for > 100 GeV counterparts to these GRBs and find no significant emission correlated with these bursts. Due to the absorption of high-energy gamma rays by the extragalactic background light (EBL), detections are only expected for redshifts less than similar to 0.5. While most long-duration GRBs occur at redshifts higher than 0.5, the opposite is thought to be true of short GRBs. Lack of a detected VHE signal thus allows setting meaningful fluence limits. One GRB in the sample (050509b) has a likely association with a galaxy at a redshift of 0.225, while another ( 051103) has been tentatively linked to the nearby galaxy M81. Fluence limits are corrected for EBL absorption, either using the known measured redshift, or computing the corresponding absorption for a redshift of 0.1 and 0.5, as well as for the case of z = 0. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Los Alamos Natl Lab, Dept Phys, Los Alamos, NM 87545 USA. George Mason Univ, Dept Phys, Fairfax, VA 22030 USA. Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico. Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. NYU, Dept Phys, New York, NY 10003 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. US FDA, Ctr Devices & Radiol Hlth, Office Sci & Engn Lab, Rockville, MD 20857 USA. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. Ohio State Univ, Lima, OH 45804 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. RP Abdo, AA (reprint author), Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. RI McEnery, Julie/D-6612-2012; Hays, Elizabeth/D-3257-2012; Casanova, Sabrina/J-8935-2013; OI Casanova, Sabrina/0000-0002-6144-9122; Dingus, Brenda/0000-0001-8451-7450; Mincer, Allen/0000-0002-6307-1418 NR 51 TC 29 Z9 29 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD SEP 1 PY 2007 VL 666 IS 1 BP 361 EP 367 DI 10.1086/519763 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 204QH UT WOS:000249058600034 ER PT J AU Lobscheid, AB McKone, TE Vallero, DA AF Lobscheid, Agnes B. McKone, Thomas E. Vallero, Daniel A. TI Exploring relationships between outdoor air particulate-associated polycyclic aromatic hydrocarbon and PM2.5: A case study of benzo(a)pyrene in California metropolitan regions SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE toxic air pollutants; particulate matter; regression models; combustion sources ID ATMOSPHERIC PARTICLES; ORGANIC-COMPOUNDS; TOXICS CONCENTRATIONS; SOURCE APPORTIONMENT; UNITED-STATES; AMBIENT AIR; URBAN AIR; SIZE; PAHS; MATTER AB Polycyclic aromatic hydrocarbons (PAHs) and particulate matter (PM) are co-pollutants emitted as by-products of combustion processes. Convincing evidence exists for PAHs as a primary toxic component of fine PM (PM2.5). Because PM2.5 is listed by the US EPA as a "Criteria Pollutant", it is monitored regularly at sites nationwide. In contrast, very limited data is available on measured ambient air concentrations of PAHs. However, between 1999 and 2001, ambient air concentrations Of PM2.5 and benzo(a)pyrene (BaP) are available for California locations. We use multivariate linear regression models (MLRMs) to predict ambient air levels of BaP in four air basins based on reported PM2.5 concentrations and spatial, temporal and meteorological variables as variates. We obtain an R-2 ranging from 0.57 to 0.72 among these basins. Significant variables (p < 0.05) include the average daily PM2.5 concentration, wind speed, temperature and relative humidity, and the coastal distance as well as season, and holiday or weekend. Combining the data from all sites and using only these variables to estimate ambient BaP levels, we obtain an R-2 of 0.55. These R-2-values, combined with analysis of the residual error and cross validation using the PRESS-statistic, demonstrate the potential of our method to estimate reported outdoor air PAH exposure levels in metropolitan regions. These MLRMs provide a first step towards relating outdoor ambient PM2.5 and PAH concentrations for epidemiological studies when PAH measurements are unavailable, or limited in spatial coverage, based on publicly available meteorological and PM2.5 data. Published by Elsevier Ltd. C1 Lawrence Berkeley Natl Lab, Indoor Environm Dept, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. US EPA, Natl Exposure Res Lab, Res Triangle Pk, NC 27711 USA. RP Lobscheid, AB (reprint author), Lawrence Berkeley Natl Lab, Indoor Environm Dept, Environm Energy Technol Div, MS90R3058, Berkeley, CA 94720 USA. EM ablobscheid@lbl.gov NR 50 TC 10 Z9 10 U1 1 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD SEP PY 2007 VL 41 IS 27 BP 5659 EP 5672 DI 10.1016/j.atmosenv.2007.02.042 PG 14 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 205WH UT WOS:000249144800009 ER PT J AU Xie, Y Berkowitz, CM AF Xie, Yulong Berkowitz, Carl M. TI The use of conditional probability functions and potential source contribution functions to identify source regions and advection pathways of hydrocarbon emissions in Houston, Texas SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE conditional probability function (CPF); potential source contribution function (PSCF); hierarchical clustering analysis (HAC); Houston; volatile organic compound (VOC); source receptor relationship ID POSITIVE MATRIX FACTORIZATION; PARTICLE-SIZE-DISTRIBUTION; SOURCE IDENTIFICATION; AIR-QUALITY; ATMOSPHERIC AEROSOL; NORTHERN VERMONT; CLUSTER-ANALYSIS; OZONE FORMATION; TRANSPORT; NOX AB In this study, we demonstrate the utility of conditional probability functions (CPFs), potential source contribution functions (PSCFs), and hierarchical clustering analysis (HAC) to identify the source region and transport pathways of hydrocarbons measured at five photochemical assessment monitoring stations (PAMS) near the Houston Ship Channel from June to October 2003. In contrast to scatter plots, which only show the pair-wise correlation of species, commonality in CPF figures shows both correlation and information on the source region of the species in question. In this study, we use over 50 hourly volatile organic compound (VOC) concentrations and surface wind observations to show that VOCs with similar CPF patterns likely have common transport pathways. This was established with the multivariate technique, which uses the hierarchical clustering analysis to define clusters of VOCs having similar CPF patterns. This method revealed that alkenes, and in particular those with geometric isomers such as cis-/trans-2-butene and cis-/trans-2-pentene, have similar CPF patterns and hence, a common area of origin. The alkane isomers often show CPF patterns among themselves, and similarly, aromatic compounds often show similar patterns. We also show how calculated trajectory information can be used in the PSCF analysis to produce a graphic picture that identifies specific geographic areas associated with a given VOC (or other pollutant). The use of these techniques in the chemically and meteorologically complex environment of Houston, Texas, suggests its further utility in other areas with relatively simpler conditions. (C) 2007 Published by Elsevier Ltd. C1 Pacific NW Natl Lab, Nat Resource Div, Richland, WA 99352 USA. RP Xie, Y (reprint author), Pacific NW Natl Lab, Nat Resource Div, 902 Battelle Blvd,POB 999, Richland, WA 99352 USA. EM yulong.xie@pnl.gov RI Xie, Yulong/O-9322-2016 OI Xie, Yulong/0000-0001-5579-482X NR 50 TC 22 Z9 24 U1 1 U2 24 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD SEP PY 2007 VL 41 IS 28 BP 5831 EP 5847 DI 10.1016/j.atmosenv.2007.03.049 PG 17 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 213AZ UT WOS:000249639600002 ER PT J AU Quinet, P Biemont, E Palmeri, P Trabert, E AF Quinet, Pascal Biemont, Emile Palmeri, Patrick Traebert, Elmar TI Relativistic atomic data for EUV and X-ray lines in the highly charged Zn-like ions from Yb40+ to U62+ SO ATOMIC DATA AND NUCLEAR DATA TABLES LA English DT Article ID ZINC ISOELECTRONIC SEQUENCE; RANDOM-PHASE-APPROXIMATION; ENERGY-LEVELS; TRANSITION-PROBABILITIES; CU-LIKE; SPECTRA; WAVELENGTHS; TRAP; ACCURATE; PROGRAM AB The wavelengths and transition probabilities for EUV and X-ray lines in the spectra from Yb XLI to U LXIII along the zinc isoelectronic sequence have been calculated using a multiconfiguration Dirac-Fock (MCDF) model. Results are reported for the 4S(2) -4s4p, 4s4p-4p(2), and 4s4p-4s4d transitions. A comparison of the calculated wavelengths with the few experimental results available is also presented. (c) 2007 Elsevier Inc. All rights reserved. C1 Univ Mons Hainaut, B-7000 Mons, Belgium. Univ Liege, IPNAS, B-4000 Liege, Belgium. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Quinet, P (reprint author), Univ Mons Hainaut, B-7000 Mons, Belgium. EM quinet@uinh.ac.be NR 27 TC 16 Z9 16 U1 1 U2 3 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0092-640X J9 ATOM DATA NUCL DATA JI Atom. Data Nucl. Data Tables PD SEP PY 2007 VL 93 IS 5 BP 711 EP 729 DI 10.1016/j.adt.2007.05.001 PG 19 WC Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Physics GA 205IH UT WOS:000249106700002 ER PT J AU Couture, A Reifarth, R AF Couture, A. Reifarth, R. TI Direct measurements of neutron capture on radioactive isotopes SO ATOMIC DATA AND NUCLEAR DATA TABLES LA English DT Article ID CROSS-SECTION MEASUREMENTS; S-PROCESS; N-TOF; NUCLEOSYNTHESIS; DETECTOR; RATES AB We simulated the response of a 47 pi calorimetric gamma-detector array to decays of radioactive isotopes on the s-process path. The GEANT 3.21 simulation package was used. The main table contains estimates on the maximum sample size and required neutron flux based on the latest available neutron capture cross-section at 30 keV. The results are intended to be used to estimate the feasibility of neutron capture measurements with 4 pi arrays using the time-of-flight technique. (c) 2007 Elsevier Inc. All rights reserved. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Reifarth, R (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM reifarth@lanl.gov NR 24 TC 14 Z9 14 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0092-640X J9 ATOM DATA NUCL DATA JI Atom. Data Nucl. Data Tables PD SEP PY 2007 VL 93 IS 5 BP 807 EP 830 DI 10.1016/j.adt.2007.06.003 PG 24 WC Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Physics GA 205IH UT WOS:000249106700006 ER PT J AU Martin, NI Derbyshire, ER Marletta, MA AF Martin, Nathaniel I. Derbyshire, Emily R. Marletta, Michael A. TI Synthesis and evaluation of a phosphonate analogue of the soluble guanylate cyclase activator YC-1 SO BIOORGANIC & MEDICINAL CHEMISTRY LETTERS LA English DT Article DE YG-1; soluble guanylate cyclase; NO signaling ID NITRIC-OXIDE; FUNCTIONAL-CHARACTERIZATION; RESONANCE RAMAN; BINDING-SITE; ENZYME; DOMAIN; NO AB Soluble guanylate cyclase (sGC) is activated by the known benzylindazole derivative YC-1 [l-benzyl-3-(5'-hydroxymethyl-2'-furyl)-indazole]. YC-1 also acts synergistically with CO, activating sGC to a level comparable to that achieved upon binding of nitric oxide, the endogenous activator of sGC. We here describe the synthesis of a YC- I phosphonate analogue with improved aqueous solubility as well as its effects on sGC. (C) 2007 Elsevier Ltd. All rights reserved. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cellular Biol, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Phys Biosci, Berkeley, CA 94720 USA. RP Marletta, MA (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM marletta@berkeley.edu NR 21 TC 5 Z9 7 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0960-894X J9 BIOORG MED CHEM LETT JI Bioorg. Med. Chem. Lett. PD SEP 1 PY 2007 VL 17 IS 17 BP 4938 EP 4941 DI 10.1016/j.bmcl.2007.06.039 PG 4 WC Chemistry, Medicinal; Chemistry, Organic SC Pharmacology & Pharmacy; Chemistry GA 205YS UT WOS:000249151700043 PM 17587571 ER PT J AU Andrews, SS Arkin, AP AF Andrews, Steven S. Arkin, Adam P. TI A mechanical explanation for cytoskeletal rings and helices in bacteria SO BIOPHYSICAL JOURNAL LA English DT Article ID DIVISION-SITE PLACEMENT; SINGLE ACTIN-FILAMENTS; ESCHERICHIA-COLI FTSZ; CELL-DIVISION; BACILLUS-SUBTILIS; PROTEIN FTSZ; SEPTAL RING; TORSIONAL RIGIDITY; GTPASE ACTIVITY; SHAPE AB Several bacterial proteins have been shown to polymerize into coils or rings on cell membranes. These include the cytoskeletal proteins MreB, FtsZ, and MinD, which together with other cell components make up what is being called the bacterial cytoskeleton. We believe that these shapes arise, at least in part, from the interaction of the inherent mechanical properties of the protein polymers and the constraints imposed by the curved cell membrane. This hypothesis, presented as a simple mechanical model, was tested with numerical energy-minimization methods from which we found that there are five low-energy polymer morphologies on a rod-shaped membrane: rings, lines, helices, loops, and polar-targeted circles. Analytic theory was used to understand the possible structures and to create phase diagrams that show which parameter combinations lead to which structures. Inverting the results, it is possible to infer the effective mechanical bending parameters of protein polymers from fluorescence images of their shapes. This theory also provides a plausible explanation for the morphological changes exhibited by the Z ring in a sporulating Bacillus subtilis; is used to calculate the mechanical force exerted on a cell membrane by a polymer; and allows predictions of polymer shapes in mutant cells. C1 Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Bioengn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. RP Andrews, SS (reprint author), Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. EM ssandrews@Ib1.gov RI Arkin, Adam/A-6751-2008 OI Arkin, Adam/0000-0002-4999-2931 NR 64 TC 26 Z9 26 U1 0 U2 5 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD SEP PY 2007 VL 93 IS 6 BP 1872 EP 1884 DI 10.1529/biophysj.106.102343 PG 13 WC Biophysics SC Biophysics GA 203ZZ UT WOS:000249013900006 PM 17513368 ER PT J AU Giannone, RJ McDonald, WH Hurst, GB Huang, Y Wu, J Liu, Y Wang, YS AF Giannone, Richard J. McDonald, W. Hayes Hurst, Gregory B. Huang, Ying Wu, Jun Liu, Yie Wang, Yisong TI Dual-tagging system for the affinity purification of mammalian protein complexes SO BIOTECHNIQUES LA English DT Article ID CELLS; PROTEOMICS; TELOMERES AB Although affinity purification coupled with mass spectrometry (MS)provides a powerful tool to study protein-protein interactions, this strategy has encountered numerous difficulties when adapted to mammalian cells. Here we describe a Gateway (R)-compatible dual-tag affinity purification system that integrates regulatable expression, tetracysteine motifs, and mrious combinations ofa ini facilitate the cloning, detection, and purification of bait proteins and their interacting partners. Utilizing the human telomere binding protein TRF2 as a benchmark, we demonstrate bait protein recoveries upwards of approxiniately 16%from as little as 1-7 x 10(7) cells and successfully identify known TRF2 interacting proteins, suggesting that our dual-tag affinity purification approach is a capable new toolfor expanding the capacity, to explore mammalian proteomic networks. C1 Oak Ridge Natl Lab, Biosci Div, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN USA. NIA, Baltimore, MD 21224 USA. RP Wang, YS (reprint author), Oak Ridge Natl Lab, Biosci Div, Oak Ridge, TN 37831 USA. EM liuyie@grc.nia.nih.gov; ywa@ornl.gov RI McDonald, W. Hayes/B-4109-2016 OI McDonald, W. Hayes/0000-0002-3510-426X FU Intramural NIH HHS NR 15 TC 19 Z9 21 U1 0 U2 3 PU INFORMA HEALTHCARE PI NEW YORK PA 52 VANDERBILT AVE, NEW YORK, NY 10017 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD SEP PY 2007 VL 43 IS 3 BP 296 EP + DI 10.2144/000112550 PG 4 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 211GD UT WOS:000249511400012 PM 17907572 ER PT J AU Jeoh, T Ishizawa, CI Davis, MF Himmel, ME Adney, WS Johnson, DK AF Jeoh, Tina Ishizawa, Claudia I. Davis, Mark F. Himmel, Michael E. Adney, William S. Johnson, David K. TI Cellulase digestibility of pretreated biomass is limited by cellulose accessibility SO BIOTECHNOLOGY AND BIOENGINEERING LA English DT Article DE dilute-acid pretreatment; pretreated corn stover; Trichoderma reesei; cellobiohydrolase; cellulase accessibility; cellulose crystallinity ID DILUTE-SULFURIC-ACID; MAJOR STRUCTURAL FEATURES; ENZYMATIC-HYDROLYSIS; TRICHODERMA-REESEI; CORN STOVER; THERMOBIFIDA-FUSCA; STEAM EXPLOSION; PORE-SIZE; ADSORPTION; SYNERGISM AB Attempts to correlate the physical and chemical properties of biomass to its susceptibility to enzyme digestion are often inconclusive or contradictory depending on variables such as the type of substrate, the pretreatment conditions and measurement techniques. In this study, we present a direct method for measuring the key factors governing cellulose digestibility in a biomass sample by directly probing cellulase binding and activity using a purified cellobiohydrolase (Cel7A) from Trichoderma reesei. Fluorescence-labeled T. reesei Cel7A was used to assay pretreated corn stover samples and pure cellulosic substrates to identify barriers to accessibility by this important component of cellulase preparations. The results showed cellulose conversion improved when T. reesei Cel7A bound in higher concentrations, indicating that the enzyme had greater access to the substrate. Factors such as the pretreatment severity, drying after pretreatment, and cellulose crystallinity were found to directly impact enzyme accessibility. This study provides direct evidence to support the notion that the best pretreatment schemes for rendering biomass more digestible to cellobiohydrolase enzymes are those that improve access to the cellulose in biomass cell walls, as well as those able to reduce the crystallinity of cell wall cellulose. C1 Chem & Biosci Ctr, Natl Renewable Energy Lab, Golden, CO 80401 USA. Natl Bioenergy Ctr, Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Johnson, DK (reprint author), Chem & Biosci Ctr, Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM David_Johnson@nrel.gov RI Johnson, David/G-4959-2011; OI Johnson, David/0000-0003-4815-8782; davis, mark/0000-0003-4541-9852 NR 41 TC 273 Z9 279 U1 9 U2 110 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0006-3592 EI 1097-0290 J9 BIOTECHNOL BIOENG JI Biotechnol. Bioeng. PD SEP 1 PY 2007 VL 98 IS 1 BP 112 EP 122 DI 10.1002/bit.21408 PG 11 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 198VN UT WOS:000248655700012 PM 17335064 ER PT J AU Porter, SE Donohoe, BS Beery, KE Xu, Q Ding, SY Vinzant, TB Abbas, CA Himmel, ME AF Porter, Stephanie E. Donohoe, Bryon S. Beery, Kyle E. Xu, Qi Ding, Shi-You Vinzant, Todd B. Abbas, Charles A. Himmel, Michael E. TI Microscopic analysis of corn fiber using starch- and cellulose-specific molecular probes SO BIOTECHNOLOGY AND BIOENGINEERING LA English DT Article DE corn fiber; carbohydrate-binding module; starch; cellulose; fluorescent probe; microscopy ID CARBOHYDRATE-BINDING MODULES; PLANT-CELL WALL; PRETREATMENT; RECOGNITION; ETHANOL AB Ethanol is the primary liquid transportation fuel produced from renewable feedstocks in the United States today. The majority of corn grain, the primary feedstock for ethanol production, has been historically processed in wet mills yielding products such as gluten feed, gluten meal, starch, and germ. Starch extracted from the grain is used to produce ethanol in saccharification and fermentation steps; however the extraction of starch is not 100% efficient. To better understand starch extraction during the wet milling process, we have developed fluorescent probes that can be used to visually localize starch and cellulose in samples using confocal microscopy. These probes are based on the binding specificities of two types of carbohydrate binding modules (CBMs), which are small substrate-specific protein domains derived from carbohydrate degrading enzymes. CBMs were fused, using molecular cloning techniques, to a green fluorescent protein (GFP) or to the red fluorescent protein DsRed (RFP). Using these engineered probes, we found that the binding of the starch-specific probe correlates with starch content in corn fiber samples. We also demonstrate that there is starch internally localized in the endosperm that may contribute to the high starch content in corn fiber. We also surprisingly found that the cellulose-specific probe did not bind to most corn fiber samples, but only to corn fiber that had been hydrolyzed using a thermochemical process that removes the residual starch and much of the hemicellulose. Our findings should be of interest to those working to increase the efficiency of the corn grain to ethanol process. C1 Chem & Biosci Ctr, Natl Renewable Energy Lab, Golden, CO 80401 USA. Archer Daniel Midland Co, James R Randall Res Ctr, Decatur, IL USA. RP Porter, SE (reprint author), Chem & Biosci Ctr, Natl Renewable Energy Lab, Golden, CO 80401 USA. EM stephanie_porter@nrel.gov RI Ding, Shi-You/O-1209-2013 NR 19 TC 15 Z9 15 U1 1 U2 11 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0006-3592 EI 1097-0290 J9 BIOTECHNOL BIOENG JI Biotechnol. Bioeng. PD SEP 1 PY 2007 VL 98 IS 1 BP 123 EP 131 DI 10.1002/bit.21409 PG 9 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 198VN UT WOS:000248655700013 PM 17335065 ER PT J AU Senocak, I Ackerman, AS Kirkpatrick, MP Stevens, DE Mansour, NN AF Senocak, Inanc Ackerman, Andrew S. Kirkpatrick, Michael P. Stevens, David E. Mansour, Nagi N. TI Study of near-surface models for large-eddy simulations of a neutrally stratified atmospheric boundary layer SO BOUNDARY-LAYER METEOROLOGY LA English DT Article DE atmospheric boundary layer; dynamic models; large-eddy simulations; near-surface models ID SUBGRID-SCALE MODEL; TURBULENT FLOWS; WALL; FLUXES; LES AB In large-eddy simulations (LES) of the atmospheric boundary layer (ABL), nearsurface models are often used to supplement subgrid-scale (SGS) turbulent stresses when a major fraction of the energetic scales within the surface layer cannot be resolved with the temporal and spatial resolution at hand. In this study, we investigate the performance of both dynamic and non-dynamic eddy viscosity models coupled with near-surface models in simulations of a neutrally stratified ABL. Two near-surface models that are commonly used in LES of the atmospheric boundary layer are considered. Additionally, a hybrid Reynolds-averaged/LES eddy viscosity model is presented, which uses Prandtl's mixing length model in the vicinity of the surface, and blends in with the dynamic Smagorinsky model away from the surface. Present simulations show that significant portions of the modelled turbulent stresses are generated by the near-surface models, and they play a dominant role in capturing the expected logarithmic wind profile. Visualizations of the instantaneous vorticity field reveal that flow structures in the vicinity of the surface depend on the choice of the near-surface model. Among the three near-surface models studied, the hybrid eddy viscosity model gives the closest agreement with the logarithmic wind profile in the surface layer. It is also observed that high levels of resolved turbulence stresses can be maintained with the so-called canopy stress model while producing good agreement with the logarithmic wind profile. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Stanford Univ, NASA Ames, Ctr Turbulence Res, Stanford, CA 94305 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Univ Sydney, Sch Aerosp Mech & Mechatron Engn, Sydney, NSW 2006, Australia. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Senocak, I (reprint author), Los Alamos Natl Lab, Mail Stop K575,POB 1663, Los Alamos, NM 87545 USA. EM senocak@lanl.gov RI Ackerman, Andrew/D-4433-2012; OI Ackerman, Andrew/0000-0003-0254-6253; Kirkpatrick, Michael/0000-0002-7157-6440 NR 42 TC 12 Z9 12 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0006-8314 J9 BOUND-LAY METEOROL JI Bound.-Layer Meteor. PD SEP PY 2007 VL 124 IS 3 BP 405 EP 424 DI 10.1007/s10546-007-9181-x PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 195MX UT WOS:000248417400005 ER PT J AU Srivastava, SC AF Srivastava, Suresh C. TI The role of electron-emitting radiopharmaceuticals in the palliative treatment of metastatic bone pain and for radiosynovectomy: Applications of conversion electron emitter tin-117m SO BRAZILIAN ARCHIVES OF BIOLOGY AND TECHNOLOGY LA English DT Article DE radionuclide therapy; conversion electron emitters; bone pain palliation; radiosynovectomy; tin-117m ID RESISTANT PROSTATE-CANCER; OSSEOUS METASTASES; THERAPEUTIC RADIOPHARMACEUTICALS; RADIATION SYNOVECTOMY; SKELETAL METASTASES; INVIVO BEHAVIOR; SR-89; RADIONUCLIDES; RADIOIMMUNOTHERAPY; SAMARIUM-153-EDTMP AB A variety of radionuclides continue to be investigated and/or clinically used for different therapeutic applications in nuclear medicine. The choice of a particular radionuclide with regard to appropriate emissions, linear energy transfer (LET), and physical half-life, etc., is dictated to a large extent by the character of the disease (e. g., solid tumor or metastatic disease), and by the carrier to selectively transport the radionuclide to the desired site. An impressive body of information has appeared in the recent literature that addresses many of these considerations. This article summarizes and discusses the role of high-LET electron emitters and their advantage in the treatment of cancer or for other disorders in specific situations. Areas such as bone pain palliation, bone malignancy therapy, and radiation synovectomy are covered in greater detail. Projections are made as to the future directions and progress in these areas. A discussion of the various issues related to the selection criteria that are useful for choosing the appropriate radionuclide for a particular application is included. Use of high-LET electron emitters is discussed in greater detail, with particular emphasis on the use of conversion electron emitter tin-117m for various therapeutic applications. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Srivastava, SC (reprint author), Brookhaven Natl Lab, Dept Med, Bldg 801,POB 5000, Upton, NY 11973 USA. EM suresh@bnl.gov NR 53 TC 6 Z9 7 U1 0 U2 1 PU INST TECNOLOGIA PARANA PI CURITIBA-PARANA PA RUA PROF ALGACYR MUNHOZ MADER 3775-CIC, 81350-010 CURITIBA-PARANA, BRAZIL SN 1516-8913 J9 BRAZ ARCH BIOL TECHN JI Braz. Arch. Biol. Technol. PD SEP PY 2007 VL 50 SI SI BP 49 EP 62 DI 10.1590/S1516-89132007000600007 PG 14 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 279WW UT WOS:000254386900007 ER PT J AU Webb-Robertson, BJM Cannon, WR AF Webb-Robertson, Bobbie-Jo M. Cannon, William R. TI Current trends in computational inference from mass spectrometry-based proteomics SO BRIEFINGS IN BIOINFORMATICS LA English DT Review DE mass spectrometry; proteomics; peptide identification; post-translational modification; protein interaction ID LARGE-SCALE PROTEOMICS; INDUCED DISSOCIATION SPECTRA; PROTEIN-INTERACTION NETWORKS; DNA-POLYMERASE HOLOENZYME; PEPTIDE SEQUENCE TAGS; AMINO-ACID-SEQUENCES; CODED AFFINITY TAGS; HIGH-THROUGHPUT; SHOTGUN PROTEOMICS; DATABASE SEARCH AB Mass spectrometry offers a high-throughput approach to quantifying the proteome associated with a biological sample and hence has become the primary approach of proteomic analyses. Computation is tightly coupled to this advanced technological platform as a required component of not only peptide and protein identification, but quantification and functional inference, such as protein modifications and interactions. Proteomics faces several key computational challenges such as identification of proteins and peptides from tandem mass spectra as well as their quantitation. In addition, the application of proteomics to systems biology requires understanding the functional proteome, including how the dynamics of the cell change in response to protein modifications and complex interactions between biomolecules. This review presents an overview of recently developed methods and their impact on these core computational challenges currently facing proteomics. C1 Pacific NW Natl Lab, Dept Computat Biol & Bioinformat, Richland, WA 99352 USA. RP Webb-Robertson, BJM (reprint author), Pacific NW Natl Lab, Dept Computat Biol & Bioinformat, POB 999, Richland, WA 99352 USA. EM bj@pnl.gov RI Cannon, William/K-8411-2014 OI Cannon, William/0000-0003-3789-7889 NR 141 TC 19 Z9 19 U1 0 U2 7 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1467-5463 J9 BRIEF BIOINFORM JI Brief. Bioinform. PD SEP PY 2007 VL 8 IS 5 BP 304 EP 317 DI 10.1093/bib/bbm023 PG 14 WC Biochemical Research Methods; Mathematical & Computational Biology SC Biochemistry & Molecular Biology; Mathematical & Computational Biology GA 232QR UT WOS:000251034700004 PM 17584764 ER PT J AU Valentine, GA Keating, GN AF Valentine, Greg A. Keating, Gordon N. TI Eruptive styles and inferences about plumbing systems at Hidden Cone and Little Black Peak scoria cone volcanoes (Nevada, USA) SO BULLETIN OF VOLCANOLOGY LA English DT Article DE scoria cone; dike; Southwest Nevada Volcanic Field ID RADIOACTIVE-WASTE REPOSITORY; SOUTHERN NEVADA; YUCCA MOUNTAIN; LATHROP WELLS; HAZARDS ASSESSMENT; DESERT PAVEMENTS; EVOLUTION; AGE; PLEISTOCENE; EMPLACEMENT AB We describe two small scoria cone volcanoes, Hidden Cone and Little Black Peak (ages between similar to 320-390 ka), in the Southwestern Nevada Volcanic Field and discuss their eruption mechanisms and inferences about their plumbing systems. Cone-forming pyroclastic deposits are consistent with eruptive styles ranging from Strombolian to violent Strombolian, and lavas emanated from near the bases of the cones. The volcanoes are monogenetic (rather than polycyclic, as allowed by previous geomorphic interpretations). Vents at each volcano appear to coincide with pre-existing normal faults, consistent with observations at older, deeply eroded volcanoes in the region. The existence of these two volcanoes on a topographically high area (particularly Hidden Cone) provides evidence for short feeder dike lengths (similar to 500 m at the surface). We infer that this short length reflects the small length scale of the mantle source region that was tapped to feed each volcano. C1 Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. RP Valentine, GA (reprint author), Los Alamos Natl Lab, Div Earth & Environm Sci, Mail Stop D462, Los Alamos, NM 87545 USA. EM gav@lanl.gov NR 29 TC 27 Z9 27 U1 0 U2 4 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0258-8900 J9 B VOLCANOL JI Bull. Volcanol. PD SEP PY 2007 VL 70 IS 1 BP 105 EP 113 DI 10.1007/s00445-007-0123-8 PG 9 WC Geosciences, Multidisciplinary SC Geology GA 204BF UT WOS:000249017100005 ER PT J AU Todd, BD Davis, AK AF Todd, Brian D. Davis, Andrew K. TI Sexual dichromatism in the marbled salamander Ambyastoma opacum SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID AMBYSTOMA-OPACUM; COLOR; DIMORPHISM; BRIGHTNESS; SELECTION; AMPHIBIA; SIGNAL; BADGE AB Reports of sexual dichromatism in salamanders are rare and have been generally restricted to a few species in the families Hynobiidae and Salamandridae. We used image analysis techniques to examine sexual dichromatism in the marbled salamander, Ambystoma opacum (Gravenhorst, 1807). We measured the average hue of white saddles on male and female marbled salamanders (n = 118), as well as the proportion of white dorsal surface area relative to the black dorsal surface area, to determine the extent of sexual dichromatism in this species. We also tested whether patterning and coloration were correlated with body size or relative body mass. Males had significantly whiter saddles and higher relative proportions of white coloration on their dorsal surfaces than did females. Furthermore, the relative proportion of white areas on the dorsum was positively correlated to body condition in both males and females. Body size was not correlated with hue or proportion of white area on the dorsum. To our knowledge, we report the first confirmation of sexually dimorphic coloration in the ambystomatid salamander family, extending the known distribution of sexual dichromatism in the order Caudata. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Univ Georgia, Warnell Sch Forestry & Nat Resources, Athens, GA 30602 USA. RP Todd, BD (reprint author), Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. EM todd@srel.edu NR 36 TC 13 Z9 15 U1 2 U2 13 PU NATL RESEARCH COUNCIL CANADA-N R C RESEARCH PRESS PI OTTAWA PA BUILDING M 55, OTTAWA, ON K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD SEP PY 2007 VL 85 IS 9 BP 1008 EP 1013 DI 10.1139/Z07-082 PG 6 WC Zoology SC Zoology GA 239HA UT WOS:000251508200009 ER PT J AU Pannala, S Daw, CS Finney, CEA Boyalakuntla, D Syamlal, M O'Brien, TJ AF Pannala, Sreekanth Daw, C. Stuart Finney, Charles E. A. Boyalakuntla, Dhanunjay Syamlal, Madhava O'Brien, Thomas J. TI Simulating the dynamics of spouted-bed nuclear fuel coaters SO CHEMICAL VAPOR DEPOSITION LA English DT Article DE computational fluid dynamics (CFD); fluidized bed dynamics; nuclear fuel particle coating; spouted-bed coaters; spouted-bed simulations ID FLUIDIZED-BED; COATING PROCESS; PARTICLES; FLOW AB We describe simulation studies of the dynamics of spouted beds used for CVD coating of nuclear fuel particles. Our principal modeling tool is the Multiphase Flow with Interphase eXchanges (NIFIX) code that was originally developed by the National Energy Technology Laboratory (NETL) for fossil energy process applications. In addition to standard MFIX features that allow coupling of transient hydrodynamics, heat and mass transfer, and chemical kinetics, we employ special post-processing tools to track particle mixing and circulation as functions of operating conditions and bed design. We describe in detail one major feature of the dynamics, which is the occurrence of very regular spontaneous pulsations of gas and particle flow in the spout. These pulsations appear to be critically linked to the entrainment and circulation of solids, and they produce readily accessible dynamic pressure variations that can be used for direct comparisons of model predictions with experiments. Spouted-bed dynamics are important from a CVD perspective because they directly determine the magnitude and variability of the concentration and species gradients in the zone where reactant gases first come into contact with hot particles. As this unsteady spouted-bed environment differs from other types of CVD reactors, the design and scale-up of such reactors is likely to involve unique modeling issues. Our primary goal here is to lay the groundwork for how computational simulation can be used to address these modeling issues in the specific context of nuclear fuel particle coating. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Natl Energy Technol Lab, Morgantown, WV 26505 USA. RP Pannala, S (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM pannalas@ornl.gov RI Pannala, Sreekanth/F-9507-2010 NR 30 TC 14 Z9 15 U1 2 U2 18 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0948-1907 J9 CHEM VAPOR DEPOS JI Chem. Vapor Depos. PD SEP PY 2007 VL 13 IS 9 BP 481 EP 490 DI 10.1002/cvde.200606562 PG 10 WC Electrochemistry; Materials Science, Coatings & Films; Physics, Condensed Matter SC Electrochemistry; Materials Science; Physics GA 216XX UT WOS:000249913400006 ER PT J AU Heinen, MA Sharma, P AF Heinen, M. A. Sharma, P. TI Public health use of poison center data SO CLINICAL TOXICOLOGY LA English DT Meeting Abstract C1 ORISE, Washington, DC USA. No New England Poison Ctr, Portland, OR USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0731-3810 J9 CLIN TOXICOL JI Clin. Toxicol. PD SEP PY 2007 VL 45 IS 6 BP 645 EP 645 PG 1 WC Toxicology SC Toxicology GA 214UE UT WOS:000249762900228 ER PT J AU Newhouse, SJ Schopf, JM AF Newhouse, Steven J. Schopf, Jennifer M. TI Grid user requirements - 2004: a perspective from the trenches SO CLUSTER COMPUTING-THE JOURNAL OF NETWORKS SOFTWARE TOOLS AND APPLICATIONS LA English DT Article DE grid functionality; security; tools; user requirements AB Pervasive Grid adoption is predicated on the availability of widely deployed usable software and a user community willing to use it. Currently, widespread adoption of Grids, even within technically sophisticated communities, is limited, and determining and eliminating these barriers to adoption are essential in order for Grids to becoming widely capitalized. Through a series of face-to-face interviews conducted during the summer of 2004, we have identified issues relating to job submission, file transfer, usability, and systems management that must be resolved in order to improve the usability of Grid infrastructures. The background to these issues and some possible solutions are described in this paper. C1 Univ Southampton, Open Middleware Infrastruct Inst, Southampton SO17 1BJ, Hants, England. Argonne Natl Lab, Argonne, IL 60439 USA. UK Natl Sci Ctr, Edinburgh EH8 9, Midlothian, Scotland. RP Newhouse, SJ (reprint author), Univ Southampton, Open Middleware Infrastruct Inst, Southampton SO17 1BJ, Hants, England. EM s.newhouse@omii.ac.uk; jms@mcs.anl.gov OI Schopf, Jennifer/0000-0003-0726-3674 NR 28 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1386-7857 J9 CLUSTER COMPUT JI Cluster Comput. PD SEP PY 2007 VL 10 IS 3 BP 311 EP 322 DI 10.1007/s10586-007-0031-x PG 12 WC Computer Science, Information Systems; Computer Science, Theory & Methods SC Computer Science GA 204OC UT WOS:000249052900006 ER PT J AU Boghosian, B Peter, C Dong, S Finn, L Jha, S Karniadakis, G Karonis, N AF Boghosian, Bruce Coveney, Peter Dong, Suchuan Finn, Lucas Jha, Shantenu Karniadakis, George Karonis, Nicholas TI NEKTAR, SPICE and Vortonics: using federated grids for large scale scientific applications SO CLUSTER COMPUTING-THE JOURNAL OF NETWORKS SOFTWARE TOOLS AND APPLICATIONS LA English DT Article DE distributed supercomputers; federated grids; interoperability; optical lightpaths; MPICH-G2; co-scheduling ID VORTEX CORE IDENTIFICATION; MOLECULAR-DYNAMICS; SIMULATION; DNA AB In response to a joint call from US's NSF and UK's EPSRC for applications that aim to utilize the combined computational resources of the US and UK, three computational science groups from UCL, Tufts and Brown Universities learned Lip with a middleware team from NIU/Argonne to meet the challenge. Although the groups had three distinct codes and aims, the projects had the large-derlying common feature that they were comprised of large-scale distributed applications which required high-end networking and advanced rniddleware in order to be effectively deployed. For example, cross-site runs were found to be a very effective strategy to overcome the limitations of a single resource. n The seamless federation of a grid-of-grids remains difficult. Even if interoperability at the middleware and software stack levels were to exist, it would not guarantee that the federated grids can be utilized for large scale distributed applications. There are important additional requirements for example, compatible and consistent usage policy, automated advanced reservations and most important of all co-scheduling. This paper outlines the scientific motivation and describes why distributed resources are critical for all three projects. It documents the challenges encountered in using a grid-of-grids and some of the solutions devised in response. C1 UCL, Ctr Comp Sci, London WC1H 0AJ, England. Tufts Univ, Dept Math, Medford, MA 02155 USA. Brown Univ, Div Appl Math, Providence, RI 02912 USA. No Illinois Univ, Dept Comp Sci, De Kalb, IL 60115 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Jha, S (reprint author), UCL, Ctr Comp Sci, London WC1H 0AJ, England. EM s.jha@ucl.ac.uk RI Dong, Suchuan/B-1529-2008; OI Dong, Suchuan/0000-0001-6778-0679 NR 31 TC 9 Z9 9 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1386-7857 J9 CLUSTER COMPUT JI Cluster Comput. PD SEP PY 2007 VL 10 IS 3 BP 351 EP 364 DI 10.1007/s10586-007-0029-4 PG 14 WC Computer Science, Information Systems; Computer Science, Theory & Methods SC Computer Science GA 204OC UT WOS:000249052900009 ER PT J AU Amantini, G Frank, JH Bennett, BAV Smooke, MD Gornez, A AF Amantini, Giuliano Frank, Jonathan H. Bennett, Beth Anne V. Smooke, Mitchell D. Gornez, Alessandro TI Comprehensive study of the evolution of an annular edge flame during extinction and reignition of a counterflow diffusion flame perturbed by vortices SO COMBUSTION AND FLAME LA English DT Article DE edge flame; vorticity-velocity formulation; counterflow diffusion flame; triple flame; premixed flame; extinction; ignition; computational combustion ID TRIPLE FLAME; MIXING LAYERS; VORTEX; DYNAMICS; STRAIN; BURNER; PROPAGATION; UNSTEADY AB The structure of a time-dependent methane/enriched-air flame established in an axisymmetric, laminar counter-flow configuration is investigated, as the flame interacts with two counterpropagating toroidal vortices. Computationally, the time-dependent equations are written using a modified vorticity-velocity formulation, with detailed chemistry and transport, and are solved implicitly on a nonstaggered, nonuniform grid. Boundary conditions are chosen to create local extinction and reignition in the vicinity of the axis of symmetry. Experimentally, CO planar laser-induced fluorescence (PLIF), OH PLIF, and an observable proportional to the forward reaction rate (RR) of the reaction CO + OH -> CO2 + H are measured. Particle image velocimetry (PIV) is used to characterize the velocity field of the vortical structures and to provide detailed boundary conditions for the simulations. Excellent agreement is found between model and experiments to the minutest morphological details throughout the interaction. The validated model is then used to probe the dynamics of the two-dimensional extinction process with high temporal resolution. During the initial phase of the interaction, the flame is locally extinguished by the two vortices. The resulting edge flame propagates outward as an extinction front, with a structure that does not depart significantly from that of a diffusion flame. The front recedes from the axis of symmetry with a negative propagation speed that reaches a value as large as six times that of the freely propagating laminar flame with the same reactant concentrations found at the stoichiometric surface. As the front propagates outward, it transitions to an ignition front, and it reaches a positive propagation speed comparable to that of the freely propagating laminar flame. During this transition, it develops a characteristic premixed '' hook,'' with a lean premixed branch, a stoichiometric segment that evolves into the remnant of the original primary diffusion flame, and a much weaker secondary diffusion flame resulting from a secondary peak in heat release in the original unperturbed diffusion flame. No evidence of a distinct rich premixed flame is found. The edge flame stabilizes at a radial location where the local gaseous speed equals the propagation speed of the front. When the local perturbation has decayed below the flame propagation speed, the flame edge starts reigniting the mixing layer as an ignition wave that propagates with an essentially frozen structure along the stoichiometric surface until the original diffusion flame structure is fully recovered. Implications for flamelet modeling of turbulent flames with local extinction are discussed.(c) 2007 The Combustion Institute. Published by Elsevier Inc. All rights reserved. C1 Yale Univ, Yale Ctr Combus Studies, Dept Mech Engn, New Haven, CT 06520 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Gornez, A (reprint author), Yale Univ, Yale Ctr Combus Studies, Dept Mech Engn, New Haven, CT 06520 USA. EM alessandro.gomez@yale.edu RI Bennett, Beth Anne/D-3263-2012 NR 37 TC 22 Z9 22 U1 2 U2 8 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD SEP PY 2007 VL 150 IS 4 BP 292 EP 319 DI 10.1016/j.combustflame.2007.04.010 PG 28 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 203QT UT WOS:000248989800003 ER PT J AU Chuang, WY Kachru, S Tomasiello, A AF Chuang, Wu-yen Kachru, Shamit Tomasiello, Alessandro TI Complex/symplectic mirrors SO COMMUNICATIONS IN MATHEMATICAL PHYSICS LA English DT Article ID CALABI-YAU MANIFOLDS; MODULI SPACE; STRING THEORY; COMPACTIFICATIONS; VACUA; THREEFOLDS; DIMENSIONS; FLUXES AB We construct a class of symplectic non-Kahler and complex non-Kahler string theory vacua, extending and providing evidence for an earlier suggestion by Polchinski and Strominger. The class admits a mirror pairing by construction. Comparing hints from a variety of sources, including ten-dimensional supergravity and KK reduction on SU(3)-structure manifolds, suggests a picture in which string theory extends Reid's fantasy to connect classes of both complex non-Kahler and symplectic non-Kahler manifolds. C1 Stanford Univ, ITP, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Menlo Pk, CA 94309 USA. RP Chuang, WY (reprint author), Stanford Univ, ITP, Stanford, CA 94305 USA. EM tomasiel@stanford.edu RI Tomasiello, Alessandro/J-1326-2014; OI Tomasiello, Alessandro/0000-0002-5772-5729; Chuang, Wu-Yen/0000-0003-3230-3252 NR 44 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0010-3616 EI 1432-0916 J9 COMMUN MATH PHYS JI Commun. Math. Phys. PD SEP PY 2007 VL 274 IS 3 BP 775 EP 794 DI 10.1007/s00220-007-0262-y PG 20 WC Physics, Mathematical SC Physics GA 195KM UT WOS:000248411100008 ER PT J AU Hetmaniuk, U AF Hetmaniuk, U. TI Stability estimates for a class of helmholtz problems SO COMMUNICATIONS IN MATHEMATICAL SCIENCES LA English DT Article DE helmholtz problems; stability estimates; mixed boundary conditions ID EQUATIONS AB This paper presents new stability estimates for the scalar Helmholtz equation with a complex-valued Robin boundary condition as well as Dirichlet and Neumann boundary conditions. For each estimate, we state the explicit dependency of constants on the wave number. To deal with mixed boundary conditions, we impose geometrical constraints on the two-dimensional or three- dimensional bounded domain. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hetmaniuk, U (reprint author), Sandia Natl Labs, POB 5800,MS 1320, Albuquerque, NM 87185 USA. EM ulhetma@sandia.gov NR 12 TC 37 Z9 38 U1 3 U2 4 PU INT PRESS PI SOMERVILLE PA PO BOX 43502, SOMERVILLE, MA 02143 USA SN 1539-6746 J9 COMMUN MATH SCI JI Commun. Math. Sci. PD SEP PY 2007 VL 5 IS 3 BP 665 EP 678 PG 14 WC Mathematics, Applied SC Mathematics GA 214GG UT WOS:000249723400008 ER PT J AU Carnes, BR Carey, GF AF Carnes, B. R. Carey, G. F. TI Estimating spatial and parameter error in parameterized nonlinear reaction-diffusion equations SO COMMUNICATIONS IN NUMERICAL METHODS IN ENGINEERING LA English DT Article DE a posteriori error estimation; nonlinear reaction; adaptive mesh refinement; pseudo-arclength continuation; turning point ID BOUNDARY-VALUE-PROBLEMS; FINITE-ELEMENT METHODS; NON-LINEAR EQUATIONS; DIFFERENTIAL-EQUATIONS; POSTERIORI AB A new approach is proposed for the a posteriori error estimation of both global spatial and parameter error in parameterized nonlinear reaction-diffusion problems. The technique is based on linear equations relating the linearized spatial and parameter error to the weak residual. Computable local element error indicators are derived for local contributions to the global spatial and parameter error, along with corresponding global error indicators. The effectiveness of the error indicators is demonstrated using model problems for the case of regular points and simple turning points. In addition, a new turning point predictor and adaptive algorithm for accurately computing turning points are introduced. Copyright (C) 2006 John Wiley & Sons, Ltd. C1 Univ Texas, Inst Computat Engn & Sci, Austin, TX 78712 USA. RP Carnes, BR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM bcarnes@sandia.gov NR 36 TC 3 Z9 3 U1 0 U2 4 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 1069-8299 J9 COMMUN NUMER METH EN JI Commun. Numer. Methods Eng. PD SEP PY 2007 VL 23 IS 9 BP 835 EP 854 DI 10.1002/cnm.928 PG 20 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 214IQ UT WOS:000249731500003 ER PT J AU Holm, DD Putkaradze, V Tronci, C AF Holm, Darryl D. Putkaradze, Vakhtang Tronci, Cesare TI Geometric dissipation in kinetic equations SO COMPTES RENDUS MATHEMATIQUE LA English DT Article ID FORMULATION AB A new symplectic variational approach is developed for modeling dissipation in kinetic equations. This approach yields a double bracket structure in phase space which generates kinetic equations representing coadjoint motion under canonical transformations. The Vlasov example admits measure-valued single-particle solutions. Such solutions are reversible. The total entropy is a Casimir, and thus it is preserved. C1 Univ London Imperial Coll Sci Technol & Med, Dept Math, London SW7 2AZ, England. Los Alamos Natl Lab, Comp & Computat Sci Div, Los Alamos, NM 87545 USA. Colorado State Univ, Dept Math, Ft Collins, CO 80523 USA. Univ Cologne, Inst Theoret Phys, D-50968 Cologne, Germany. TERA, Fdn Oncol Hadrontherapy, I-28100 Novara, Italy. RP Holm, DD (reprint author), Univ London Imperial Coll Sci Technol & Med, Dept Math, London SW7 2AZ, England. EM d.holm@imperial.ac.uk; putkarad@math.colostate.edu; cesare.tronci@imperial.ac.uk RI Tronci, Cesare/B-7542-2016; OI Tronci, Cesare/0000-0002-8868-8027; Holm, Darryl D/0000-0001-6362-9912 NR 20 TC 5 Z9 5 U1 1 U2 2 PU ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS PA 23 RUE LINOIS, 75724 PARIS, FRANCE SN 1631-073X J9 CR MATH JI C. R. Math. PD SEP 1 PY 2007 VL 345 IS 5 BP 297 EP 302 DI 10.1016/j.crma.2007.07.001 PG 6 WC Mathematics SC Mathematics GA 217FW UT WOS:000249934800013 ER PT J AU Mezei, F AF Mezei, Ferenc TI New perspectives from new generations of neutron sources SO COMPTES RENDUS PHYSIQUE LA English DT Article DE neutron scattering; neutron sources; high power neutron sources; pulsed sources; spallation; fusion AB Since the early 1950s the vital multidisciplinary progress in understanding condensed matter is, in a substantial fraction, based on results of neutron scattering experiments. Neutron scattering is an inherently intensity limited method and after 50 years of considerable advance-primarily achieved by improving the scattering instruments-the maturation of the technique Of Pulsed spallation sources now opens up the way to provide more neutrons with improved cost and energy efficiency. A quantitative analysis of the figure-of-merit of the specialized instruments for pulsed source operation shows that up to 2 orders of magnitude intensity gains can be achieved in the next decade, with the advent of high power spallation sources. The first stations oil this road, the MW class short pulse spallation Sources SNS in the USA (under commissioning), and J-PARC in Japan (under construction) will be followed by the 5 MW long pulse European Spallation Source (ESS). Further progress, that can be envisaged on the longer term, could amount to as much as another factor of 10 improvement. C1 [Mezei, Ferenc] Budapest Neutron Ctr, SzFKI, H-1121 Budapest, Hungary. [Mezei, Ferenc] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mezei, F (reprint author), Budapest Neutron Ctr, SzFKI, Konkoly Thege 29-33, H-1121 Budapest, Hungary. EM mezei@lanl.gov NR 7 TC 8 Z9 8 U1 2 U2 11 PU ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS PA 23 RUE LINOIS, 75724 PARIS, FRANCE SN 1631-0705 J9 CR PHYS JI C. R. Phys. PD SEP-OCT PY 2007 VL 8 IS 7-8 BP 909 EP 920 DI 10.1016/j.crhy.2007.10.003 PG 12 WC Astronomy & Astrophysics; Physics, Multidisciplinary SC Astronomy & Astrophysics; Physics GA 255DA UT WOS:000252635800013 ER PT J AU Kos, S Hruska, M Crooker, SA Saxena, A Smith, DL AF Kos, Simon Hruska, Marina Crooker, Scott A. Saxena, Avadh Smith, Darryl L. TI Modeling spin-polarized electron transport in semiconductors for spintronics applications SO COMPUTING IN SCIENCE & ENGINEERING LA English DT Article AB A primary goal in semiconductor spintronics is to develop a new generation of functional devices that exploit not only an electron's charge ( as in today's electronics industry) but also its spin. The authors show how a system of coupled spin drift-diffusion equations can accurately model spin-polarized electron transport in semiconductors. Numerical solutions allow for direct and quantitative comparison with experimental imaging data. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kos, S (reprint author), Univ Cambridge, Dept Phys, Cambridge CB3 0HE, England. EM sk460@cam.ac.uk; hruska@chevron.com; crooker@lanl.gov; avadh@lanl.gov; dsmith@lanl.gov RI Kos, Simon/G-3289-2016 OI Kos, Simon/0000-0003-1657-9793 NR 10 TC 0 Z9 0 U1 1 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1521-9615 J9 COMPUT SCI ENG JI Comput. Sci. Eng. PD SEP-OCT PY 2007 VL 9 IS 5 BP 46 EP 52 DI 10.1109/MCSE.2007.104 PG 7 WC Computer Science, Interdisciplinary Applications SC Computer Science GA 200XV UT WOS:000248797000007 ER PT J AU Taylor, C Endicott-Popovsky, B Frincke, DA AF Taylor, Carol Endicott-Popovsky, Barbara Frincke, Deborah A. TI Specifying digital forensics: A forensics policy approach SO DIGITAL INVESTIGATION LA English DT Article; Proceedings Paper CT 7th Annual DFRWS Conference 2007 CY AUG 13-15, 2007 CL Pittsburgh, PA DE digital forensics; policy; computer security; system specification; forensic properties AB In this paper we present an approach to digital forensics specification based on forensic policy definition. Our methodology borrows from computer security policy specification, which has accumulated a significant body of research over the past 30 years. We first define the process of specifying forensics properties through a forensics policy and then present an example application of the process. This approach lends itself to formal policy specification and verification, which would allow for more clarity and less ambiguity in the specification process. (C) 2007 DFRWS. Published by Elsevier Ltd. All rights reserved. C1 [Taylor, Carol] Univ Idaho, Dept Comp Sci, Moscow, ID 83844 USA. [Endicott-Popovsky, Barbara] Univ Washington, Ctr Informat Assurance & Cybersecur, Seattle, WA 98105 USA. [Frincke, Deborah A.] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Taylor, C (reprint author), Univ Idaho, Dept Comp Sci, Moscow, ID 83844 USA. EM ctaylor@cs.uidaho.edu; endicott@u.washington.edu; deborah.frincke@pnl.gov NR 8 TC 3 Z9 3 U1 1 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1742-2876 J9 DIGIT INVEST JI Digit. Investig. PD SEP PY 2007 VL 4 SU 1 BP S101 EP S104 DI 10.1016/j.diin.2007.06.006 PG 4 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications SC Computer Science GA 294RS UT WOS:000255423800015 ER PT J AU Park, SH Oh, SW Kang, SH Belharouak, I Amine, K Sun, YK AF Park, S. H. Oh, S.-W. Kang, S. H. Belharouak, I. Amine, K. Sun, Y.-K. TI Comparative study of different crystallographic structure of LiNi0.5Mn1.5O4-delta cathodes with wide operation voltage (2.0-5.0 V) SO ELECTROCHIMICA ACTA LA English DT Article DE Li-ion battery; cathode materials; LiNi0.5Mn1.5O4; electrochemical properties; spinel materials ID SECONDARY LITHIUM BATTERIES; OXIDES; NI; CO AB LiNi0.5Mn1.5O4-delta cathode materials with two different structures (Fd (3) over barm and P4(3)32) were synthesized by ultrasonic spray pyrolysis method. The X-ray diffraction (XRD) data was confirmed that face-centered spinel (Fd (3) over barm) transformed into primitive simple cubic (P4(3)32) structure by annealing process at 700 degrees C. In spite of two electrons operated cut-off voltage range between 2.0 and 5.0 V, LiNi0.5Mn1.5O4 with P4(3)32 structure has better electrochemical behaviors than the cathode with simple cubic (3) over bar structure. Ex situ XRD study of the electrode revealed that LiNi0.5Mn1.5O4 (P4(3)32) has reversible crystal transformation between fully lithiated state (2.0 V) and delithiated state (5.0 V) whereas LiNi0.5Mn1.5O4-delta (Fd (3) over barm) showed irreversible phase transformed at two voltage region. The LiNi0.5Mn1.5O4-delta (Fd (3) over barm) has voltage drop was occurred after 20th cycled compared without any voltage drop of the P4(3)32 structure. (C) 2007 Elsevier Ltd. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Hanyang Univ, Dept Chem Engn, Seoul 133791, South Korea. RP Sun, YK (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM swoh75@ihanyang.ac.kr RI Kang, Sun-Ho/E-7570-2010; Sun, Yang-Kook/B-9157-2013; Amine, Khalil/K-9344-2013 OI Sun, Yang-Kook/0000-0002-0117-0170; NR 17 TC 73 Z9 76 U1 7 U2 60 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD SEP PY 2007 VL 52 IS 25 BP 7226 EP 7230 DI 10.1016/j.electacta.2007.05.050 PG 5 WC Electrochemistry SC Electrochemistry GA 209ZK UT WOS:000249426300006 ER PT J AU Smith, KA Rahn, CD Wang, CY AF Smith, Kandler A. Rahn, Christopher D. Wang, Chao-Yang TI Control oriented ID electrochemical model of lithium ion battery SO ENERGY CONVERSION AND MANAGEMENT LA English DT Article DE lithium ion battery; electrochemical model; state of charge estimation; hybrid electric vehicle; distributed parameter model order reduction ID INSERTION CELL; AUTOMOTIVE BATTERIES; STATE; CHARGE; IMPEDANCE; DISCHARGE; SIMULATION; SYSTEMS AB Lithium ion (Li-ion) batteries provide high energy and power density energy storage for diverse applications ranging from cell phones to hybrid electric vehicles (HEVs). For efficient and reliable systems integration, low order dynamic battery models are needed. This paper introduces a general method to generate numerically a fully observable/controllable state variable model from electrochemical kinetic, species and charge partial differential equations that govern the discharge/charge behavior of a Li-ion battery. Validated against a 313th order nonlinear CFD model of a 6 Ah HEV cell, a 12th order state variable model predicts terminal voltage to within 1% for pulse and constant current profiles at rates up to 50 C. The state equation is constructed in modal form with constant negative real eigen-values distributed in frequency space from 0 to 10 Hz. Open circuit potential, electrode surface concentration/reaction distribution coupling and electrolyte concentration/ionic conductivity nonlinearities are explicitly approximated in the model output equation on a local, electrode-averaged and distributed basis, respectively. The balanced realization controllability/observability gramian indicates that the fast electrode surface concentration dynamics are more observable/controllable than the electrode bulk concentration dynamics (i.e. state of charge). (c) 2007 Elsevier Ltd. All rights reserved. C1 Penn State Univ, Dept Mech & Nucl Engn, University Pk, PA 16802 USA. Natl Renewable Energy Lab, Ctr Tranportat Technol & Syst, Golden, CO 80401 USA. RP Rahn, CD (reprint author), Penn State Univ, Dept Mech & Nucl Engn, University Pk, PA 16802 USA. EM cdrahn@psu.edu RI Wang, Chao-Yang/C-4122-2009 NR 23 TC 126 Z9 129 U1 7 U2 51 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0196-8904 J9 ENERG CONVERS MANAGE JI Energy Conv. Manag. PD SEP PY 2007 VL 48 IS 9 BP 2565 EP 2578 DI 10.1016/j.enconman.2007.03.015 PG 14 WC Thermodynamics; Energy & Fuels; Mechanics SC Thermodynamics; Energy & Fuels; Mechanics GA 206RD UT WOS:000249199700016 ER PT J AU Winans, RE Tomczyk, NA Hunt, JE Solum, MS Pugmire, RJ Jiang, YJ Fletcher, TH AF Winans, Randall E. Tomczyk, Nancy A. Hunt, Jerry E. Solum, Mark S. Pugmire, Ronald J. Jiang, Yi Jin Fletcher, Thomas H. TI Model compound study of the pathways for aromatic hydrocarbon formation in soot SO ENERGY & FUELS LA English DT Article ID HIGH-TEMPERATURE PYROLYSIS; FLAMES; ANTHRACENE; PRECURSORS; ACETYLENE; PLASMA; NMR AB As a follow-up of previous work on the flame pyrolysis of biphenyl and pyrene, a more detailed analysis of the pyrolytic products has been done using additional NMR data obtained on the whole soot sample correlated with detailed high-resolution and GC mass spectrometry data on the solvent-extracted portion of the same samples. These latter data complement the earlier NMR data with details of the pre-sooting structures, referred to as "young soot", in pyrolyzed biphenyl samples collected at 1365, 1410, and 1470 K and pyrene at 1410 and 1470 K. The data reveal the roles played by free-radical-assisted polymerization reactions as well as the hydrogen-abstraction carbon-addition (HACA) reactions for the biphenyl pyrolysis. The mass spectroscopy data of pyrene describe a much different set of reactions due to polymerization which employs free-radical reactions of the pyrene due primarily to hydrogen abstraction followed by the formation of biaryl linkages at mass numbers up to five times that of the parent pyrene. Conceptual schema of reaction mechanisms are proposed to explain the formation pathways to materials detected in the soot extracts. C1 Argonne Natl Lab, Chem & X ray Sci Div, Argonne, IL 60439 USA. Univ Utah, Dept Chem, Dept Chem Engn, Salt Lake City, UT 84112 USA. Brigham Young Univ, Dept Chem Engn, Provo, UT 84602 USA. RP Winans, RE (reprint author), Argonne Natl Lab, Chem & X ray Sci Div, Argonne, IL 60439 USA. EM rewinans@anl.gov NR 25 TC 8 Z9 8 U1 1 U2 17 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD SEP-OCT PY 2007 VL 21 IS 5 BP 2584 EP 2593 DI 10.1021/ef070161p PG 10 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 212PC UT WOS:000249608300015 ER PT J AU Sweeney, JJ Roberts, JJ Harbert, PE AF Sweeney, Jerry J. Roberts, Jeffery J. Harbert, Philip E. TI Study of dielectric properties of dry and saturated green river oil shale SO ENERGY & FUELS LA English DT Article ID ELECTRICAL-CONDUCTIVITY; FREQUENCY AB We measured the dielectric permittivity of dry and fluid saturated Green River oil shale samples over a frequency range of 1 MHz to 1.8 GHz. Dry sample measurements were carried out between room temperature and 146 degrees C; saturated sample measurements were carried out at room temperature. Samples obtained from the Green River formation of Wyoming and from the Anvil Points Mine in Colorado were cored both parallel and perpendicular to layering. The samples, which all had organic richnesses in the range of 0.04-0.19 L/kg (10-45 gal/ton), showed small variations between samples and a relatively small level of anisotropy of dielectric properties when dry. The real and imaginary part of the relative dielectric permittivity of dry rock was nearly constant over the frequency range observed, with low values for the imaginary part (loss factor). Saturation with deionized water and brine greatly increased the values of the real and imaginary parts of the relative permittivity, especially at the lower frequencies. Temperature effects were relatively small, with initial increases in permittivity to about 60 degrees C, followed by slight decreases in permittivity that diminished as the temperature increased. Implications of these observations for the in situ electromagnetic or radio frequency heating of oil shale to produce oil and gas are discussed. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Sweeney, JJ (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. EM sweeney3@llnl.gov NR 22 TC 12 Z9 12 U1 2 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD SEP-OCT PY 2007 VL 21 IS 5 BP 2769 EP 2777 DI 10.1021/ef070150w PG 9 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 212PC UT WOS:000249608300037 ER PT J AU Carpenter, DL Deutch, SP French, RJ AF Carpenter, Daniel L. Deutch, Steve P. French, Richard J. TI Quantitative measurement of Biomass gasifier tars using a molecular-beam mass spectrometer: Comparison with traditional impinger sampling SO ENERGY & FUELS LA English DT Article ID PYROLYSIS; QUANTIFICATION AB Removal of tars produced during biomass gasification continues to be a technical barrier confronted by developers of commercial thermochernical conversion systems. Quantitative measurement of tar in the synthesis gas (syngas) stream is important to assess the effectiveness of cleanup and conditioning processes and verify the suitability of the cleaned syngas for its intended downstream use (e.g., catalytic conversion to liquid fuels, hydrogen recovery, or electricity production). In an effort to advance the art of gasifier tar measurement and address some limitations of traditional impinger sampling, we have investigated the use of a molecular-beam mass spectrometer (NIBMS) sampling system as an alternative method for quantifying real-time tar concentrations in biomass gasifier-derived syngas. The 0.5 ton/day pilot-scale biomass gasification system of the National Renewable Energy Laboratory (NREL) has enabled direct comparisons between NIBMS sampling and replicate impinger sampling during continuous operations. The results have shown some systematic differences between the methods, although they do appear correlated. Using a synthetic tar mixture, as well as actual corn-stoverderived syngas, experiments were carried out to compare the accuracy of the two methods. Both methods demonstrated good reproducibility, but the NIBMS measurements appear to be more accurate. Tar concentrations determined from impinger sampling averaged 11-21% lower than expected, depending upon the compound. Average MBMS measurements were within 6% of the known values, demonstrating that the MBMS can be used to improve quantitative, continuous, real-time monitoring of gasifier tar. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Carpenter, DL (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM daniel_carpenter@nrel.gov NR 16 TC 33 Z9 34 U1 0 U2 23 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD SEP-OCT PY 2007 VL 21 IS 5 BP 3036 EP 3043 DI 10.1021/ef070193c PG 8 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 212PC UT WOS:000249608300073 ER PT J AU Denholm, P Margolis, RM AF Denholm, Paul Margolis, Robert M. TI Evaluating the limits of solar photovoltaics (PV) in electric power systems utilizing energy storage and other enabling technologies SO ENERGY POLICY LA English DT Article DE solar; photovoltaics; energy storage AB In this work, we evaluate technologies that will enable solar photovoltaics (PV) to overcome the limits of traditional electric power systems. We performed simulations of a large utility system using hourly solar insolation and load data and attempted to provide up to 50% of this system's energy from PV. We considered several methods to avoid the limits of unusable PV that result at high penetration due to the use of inflexible baseload generators. The enabling technologies considered in this work are increased system flexibility, load shifting via demand responsive appliances, and energy storage. (C) 2007 Elsevier Ltd. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Natl Renewable Energy Lab, Washington, DC 20024 USA. RP Denholm, P (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM Paul_denholm@nrel.gov; margolis@nrel.gov NR 12 TC 106 Z9 108 U1 0 U2 24 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD SEP PY 2007 VL 35 IS 9 BP 4424 EP 4433 DI 10.1016/j.enpol.2007.03.004 PG 10 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 214ML UT WOS:000249741900003 ER PT J AU Maribu, KM Firestone, RM Marnayb, C Siddiqui, AS AF Maribu, Karl Magnus Firestone, Ryan M. Marnayb, Chris Siddiqui, Afzal S. TI Distributed energy resources market diffusion model SO ENERGY POLICY LA English DT Article DE distributed generation; technology market diffusion; research valuation ID TECHNOLOGY AB Distributed energy resources (DER) technologies, such as gas-fired reciprocating engines and microturbines, can be economically beneficial in meeting commercial-sector energy loads. Even with a lower electric-only efficiency than traditional central stations, combined heat and power (CHP) applications can increase overall system energy efficiency. From a policy perspective, it is useful to have good estimates of penetration rates of DER under different economic and regulatory scenarios. We model the diffusion of DER in the US commercial building sector under various technical research and technology outreach scenarios. Technology market diffusion is assumed to depend on the system's economic attractiveness and the developer's knowledge about the technology. To account for regional differences in energy markets and climates, as well as the economic potential for different building types, optimal DER systems are found for several building types and regions. Technology diffusion is predicted via a baseline and a program scenario, in which more research improves DER performance. The results depict a large and diverse market where the West region and office building may play a key role in DER adoption. With the market in an early stage, technology research and outreach programs may shift building energy consumption to a more efficient alternative. (C) 2007 Elsevier Ltd. All rights reserved. C1 Norwegian Univ Sci & Technol, Dept Elect Power Engn, N-7491 Trondheim, Norway. Ernest Orlando Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. UCL, Dept Stat Sci, London WC1E 6BT, England. RP Maribu, KM (reprint author), Norwegian Univ Sci & Technol, Dept Elect Power Engn, N-7491 Trondheim, Norway. EM kmaribu@gmail.com NR 11 TC 18 Z9 21 U1 0 U2 7 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD SEP PY 2007 VL 35 IS 9 BP 4471 EP 4484 DI 10.1016/j.enpol.2007.03.005 PG 14 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 214ML UT WOS:000249741900008 ER PT J AU Turner, CJ Crawford, RH Campbell, MI AF Turner, Cameron J. Crawford, Richard H. Campbell, Matthew I. TI Multidimensional sequential sampling for NURBs-based metamodel development SO ENGINEERING WITH COMPUTERS LA English DT Article DE non uniform rational B-splines; metamodels; sequential sampling; sampling criteria; cooling schedule; multicriteria sampling ID GLOBAL OPTIMIZATION; DESIGN; ALGORITHM AB Adaptive design of experiments approaches are intended to overcome the limitations of a priori experimental design by adapting to the results of prior runs so that subsequent runs yield more significant information. Such approaches are valuable in engineering applications with metamodels, where efficiently collecting a dataset to define an unknown function is important. While a variety of approaches have been proposed, most techniques are limited to sampling for only one phenomenon at a time. We propose a multicriteria optimization approach that effectively simultaneously samples for multiple phenomena. In addition to determining the next sequential sampling point, such an algorithm also can be formulated to support conclusions about the adequacy of the experiment through the use of convergence criteria. A multicriteria adaptive sequential sampling algorithm, along with convergence metrics, is defined and demonstrated on five trial problems of engineering interest. The results of these five problems demonstrate that a multicriteria sequential sampling approach is a useful engineering tool for modeling engineering design spaces using NURBs-based metamodels. C1 Los Alamos Natl Lab, Plutonium Mfg & Technol Div, Los Alamos, NM 87545 USA. Univ Texas, Dept Mech Engn, Univ Stn 1, Austin, TX 78712 USA. RP Turner, CJ (reprint author), Los Alamos Natl Lab, Plutonium Mfg & Technol Div, POB 1663,MS J580, Los Alamos, NM 87545 USA. EM cturner@alumni.utexas.net; rhc@mail.utexas.edu; mc1@mail.utexas.edu RI Campbell, Matthew/B-5334-2009; Turner, Cameron/N-7266-2014 OI Campbell, Matthew/0000-0003-1296-6542; Turner, Cameron/0000-0001-9546-2328 NR 37 TC 13 Z9 14 U1 0 U2 5 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0177-0667 J9 ENG COMPUT-GERMANY JI Eng. Comput. PD SEP PY 2007 VL 23 IS 3 BP 155 EP 174 DI 10.1007/s00366-006-0051-9 PG 20 WC Computer Science, Interdisciplinary Applications; Engineering, Mechanical SC Computer Science; Engineering GA 194EJ UT WOS:000248326800002 ER PT J AU Grahame, TJ AF Grahame, Thomas J. TI Mortality from copper smelter emissions circa 1967 SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Letter ID PARTICULATE MATTER; AIR-POLLUTION; UTAH VALLEY; BLOOD LEAD; PARTICLES; DISEASE; DEATH; PM10 C1 US DOE, Washington, DC USA. RP Grahame, TJ (reprint author), US DOE, Washington, DC USA. EM thomas.grahame@hq.doe.gov NR 15 TC 1 Z9 1 U1 0 U2 2 PU US DEPT HEALTH HUMAN SCIENCES PUBLIC HEALTH SCIENCE PI RES TRIANGLE PK PA NATL INST HEALTH, NATL INST ENVIRONMENTAL HEALTH SCIENCES, PO BOX 12233, RES TRIANGLE PK, NC 27709-2233 USA SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD SEP PY 2007 VL 115 IS 9 BP A439 EP A439 DI 10.1289/ehp.1044.1 PG 1 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 206RM UT WOS:000249200600001 PM 17805395 ER PT J AU Madden, AS Smith, AC Balkwill, DL Fagan, LA Phelps, TJ AF Madden, Andrew S. Smith, April C. Balkwill, David L. Fagan, Lisa A. Phelps, Tommy J. TI Microbial uranium immobilization independent of nitrate reduction SO ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID CONTAMINATED SUBSURFACE SEDIMENTS; U(VI) REDUCTION; U(IV) OXIDATION; GROUND-WATER; COMB. NOV; GEN. NOV.; BIOREMEDIATION; COMMUNITIES; AQUIFER; MINERALS AB At many uranium processing and handling facilities, including sites in the US Department of Energy (DOE) complex, high levels of nitrate are present as co-contamination with uranium in groundwater. The daunting prospect of complete nitrate removal prior to the reduction of uranium provides a strong incentive to explore bioremediation strategies that allow for uranium bioreduction and stabilization in the presence of nitrate. Typical in situ strategies involving the stimulation of metal-reducing bacteria are hindered by low-pH environments and require that the persistent nitrate must first and continuously be removed or transformed prior to uranium being a preferred electron acceptor. This work investigated the possibility of stimulating nitrate-indifferent, pH-tolerant microorganisms to achieve bioreduction of U(VI) despite nitrate persistence. Enrichments from U-contaminated sediments demonstrated nearly complete reduction of uranium with very little loss of nitrate from pH 5.7-6.2 using methanol or glycerol as a carbon source. Bacterial 16S rRNA genes were amplified from uranium-reducing enrichments (pH 5.7-6.2) and sequenced. Phylogenetic analyses classified the clone sequences into four distinct clusters. Data from sequencing and terminal-restriction fragment length polymorphism (T-RFLP) profiles indicated that the majority of the microorganisms stimulated by these enrichment conditions consisted of low G+C Gram-positive bacteria most closely related to Clostridium and Clostridium-like organisms. This research demonstrates that the stimulation of a natural microbial community to immobilize U through bioreduction is possible without the removal of nitrate. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Florida State Univ, Coll Med, Tallahassee, FL 32306 USA. RP Phelps, TJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM phelpstj@ornl.gov RI phelps, tommy/A-5244-2011 NR 55 TC 23 Z9 23 U1 1 U2 12 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 1462-2912 J9 ENVIRON MICROBIOL JI Environ. Microbiol. PD SEP PY 2007 VL 9 IS 9 BP 2321 EP 2330 DI 10.1111/j.1462-2920.2007.01347x PG 10 WC Microbiology SC Microbiology GA 198AC UT WOS:000248598400017 PM 17686028 ER PT J AU DuRant, SE Hopkins, WA Talent, LG AF DuRant, Sarah E. Hopkins, William A. Talent, Larry G. TI Impaired terrestrial and arboreal locomotor performance in the western fence lizard (Sceloporus occidentalis) after exposure to an AChE-inhibiting pesticide SO ENVIRONMENTAL POLLUTION LA English DT Article DE carbaryl; cholinesterase; reptiles; lizards; locomotor performance ID SPRINT PERFORMANCE; SWIMMING PERFORMANCE; ANOLIS LIZARDS; CARASSIUS-AURATUS; BODY-SIZE; CARBARYL; ACETYLCHOLINESTERASE; CARBOFURAN; BEHAVIOR; ORGANOPHOSPHORUS AB We examined the effects of a commonly used AChE-inhibiting pesticide on terrestrial and arboreal sprint performance, important traits for predator avoidance and prey capture, in the western fence lizard (Sceloporus occidentalis). Lizards were exposed to carbaryl (2.5, 25, and 250 mu g/g) and were raced before and 4, 24, and 96 h after dosing. In the terrestrial setting, exposure to low concentrations of carbaryl had stimulatory effects on performance, but exposure to the highest concentration was inhibitory. No stimulatory effects of carbaryl were noted in the arboreal environment and performance in lizards was reduced after exposure to both the medium and highest dose of carbaryl. Our findings suggest that acute exposure to high concentrations of carbaryl can have important sublethal consequences on fitness-related traits in reptiles and that arboreal locomotor performance is a more sensitive indicator of AChE-inhibiting pesticide poisoning than terrestrial locomotor performance. (c) 2007 Elsevier Ltd. All rights reserved. C1 Virginia Polytech Inst & State Univ, Dept Fisheries & Wildlife Sci, Wildlife Ecotoxicol & Physiol Ecol Program, Blacksburg, VA 24061 USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Oklahoma State Univ, Dept Zool, Stillwater, OK 74078 USA. RP Hopkins, WA (reprint author), Virginia Polytech Inst & State Univ, Dept Fisheries & Wildlife Sci, Wildlife Ecotoxicol & Physiol Ecol Program, 444 Latham Hall, Blacksburg, VA 24061 USA. EM hopkinsw@vt.edu NR 56 TC 23 Z9 24 U1 2 U2 6 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0269-7491 J9 ENVIRON POLLUT JI Environ. Pollut. PD SEP PY 2007 VL 149 IS 1 BP 18 EP 24 DI 10.1016/j.envpol.2006.12.025 PG 7 WC Environmental Sciences SC Environmental Sciences & Ecology GA 202DR UT WOS:000248882700003 PM 17360091 ER PT J AU Unrine, JM Hopkins, WA Romanek, CS Jackson, BP AF Unrine, Jason M. Hopkins, William A. Romanek, Christopher S. Jackson, Brian P. TI Bioaccumulation of trace elements in omnivorous amphibian larvae: Implications for amphibian health and contaminant transport SO ENVIRONMENTAL POLLUTION LA English DT Article DE trace element; amphibian; bioaccumulation; coral combustion waste; stable isotope ID BULLFROGS RANA-CATESBEIANA; DIETARY MERCURY EXPOSURE; COAL-COMBUSTION WASTES; FOOD-WEB; SPHENOCEPHALA LARVAE; BIVALVE CORBICULA; TROPHIC POSITION; STABLE NITROGEN; CARBON ISOTOPES; BUFO-TERRESTRIS AB Despite the influence that amphibians have on the flow of energy and nutrients in ecological systems, the role that amphibians play in transporting contaminants through food webs has received very little attention. This study was undertaken to investigate bioaccumulation of trace elements in amphibians relative to other small aquatic organisms in a contaminated wetland. We collected bullfrog larvae (Rana catesbeiana) along with three other species of small vertebrates and four species of invertebrates from a site contaminated with a wide array of trace elements and analyzed them for trace element concentrations and stable nitrogen and carbon isotope composition. We found that amphibian larvae accumulated the highest concentrations of most trace elements, possibly due to their feeding ecology. These results suggest that omnivorous amphibian larvae can serve as a critical link for trace element trophic transfer. Their propensity to accumulate trace elements may have important implications for amphibian health in contaminated environments and should be further investigated. (c) 2007 Elsevier Ltd. All rights reserved. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Virginia Polytech Inst & State Univ, Dept Fisheries & Wildlife Sci, Blacksburg, VA 24061 USA. Univ Georgia, Dept Geol, Athens, GA 30602 USA. Dartmouth Coll, Dept Chem & Earth Sci, Hanover, NH 03755 USA. RP Unrine, JM (reprint author), Univ Georgia, Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. EM unrine@sref.edu OI Unrine, Jason/0000-0003-3012-5261 NR 68 TC 47 Z9 51 U1 1 U2 22 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0269-7491 EI 1873-6424 J9 ENVIRON POLLUT JI Environ. Pollut. PD SEP PY 2007 VL 149 IS 2 BP 182 EP 192 DI 10.1016/j.envpol.2007.01.039 PG 11 WC Environmental Sciences SC Environmental Sciences & Ecology GA 212MS UT WOS:000249601200007 PM 17399874 ER PT J AU Wilson, EJ Friedmann, SJ Pollak, MF AF Wilson, Elizabeth J. Friedmann, S. Julio Pollak, Melisa F. TI Research for deployment: Incorporating risk, regulation, and liability for carbon capture and sequestration SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID CO2; STORAGE; INJECTION AB Carbon capture and sequestration (CCS) has the potential to enable deep reductions in global carbon dioxide (CO2) emissions, however this promise can only be fulfilled with large-scale deployment. For this to happen, CCS must be successfully embedded into a larger legal and regulatory context, and any potential risks must be effectively managed. We developed a list of outstanding research and technical questions driven by the demands of the regulatory and legal systems for the geologic sequestration (GS) component of CCS. We then looked at case studies that bound uncertainty within two of the research themes that emerge. These case studies, on surface leakage from abandoned wells and groundwater quality impacts from metals mobilization, illustrate how research can inform decision makers on issues of policy, regulatory need, and legal considerations. A central challenge is to ensure that the research program supports development of general regulatory and legal frameworks, and also the development of geological, geophysical, geochemical, and modeling methods necessary for effective GS site monitoring and verification (M&V) protocols, as well as mitigation and remediation plans. If large-scale deployment of GS is to occur in a manner that adequately protects human and ecological health and does not discourage private investment, strengthening the scientific underpinnings of regulatory and legal decision-making is crucial. C1 Univ Minnesota, Hubert H Humphrey Inst Publ Affairs, Minneapolis, MN 55455 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wilson, EJ (reprint author), Univ Minnesota, Hubert H Humphrey Inst Publ Affairs, 301 19th Ave S, Minneapolis, MN 55455 USA. EM evilson@umn.edu NR 39 TC 67 Z9 67 U1 1 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD SEP 1 PY 2007 VL 41 IS 17 BP 5945 EP 5952 DI 10.1021/es062272t PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 207GR UT WOS:000249240100012 PM 17937265 ER PT J AU Weschler, CJ Wisthaler, A Cowlin, S Tamas, G Strom-Tejsen, P Hodgson, AT Destaillats, H Herrington, J Zhang, JJ Nazaroff, WW AF Weschler, Charles J. Wisthaler, Armin Cowlin, Shannon Tamas, Gyongyi Strom-Tejsen, Peter Hodgson, Alfred T. Destaillats, Hugo Herrington, Jason Zhang, Junfeng Jim Nazaroff, William W. TI Ozone-initiated chemistry in an occupied simulated aircraft cabin SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID INDOOR SECONDARY POLLUTANTS; VOLATILE ORGANIC-COMPOUNDS; SPECTROMETRY PTR-MS; MASS-SPECTROMETRY; ALDEHYDES; EMISSIONS; REMOVAL; ENVIRONMENT; EXPOSURES; PRODUCTS AB We have used multiple analytical methods to characterize the gas-phase products formed when ozone was added to cabin air during simulated 4-hour flights that were conducted in a reconstructed section of a B-767 aircraft containing human occupants. Two separate groups of 16 females were each exposed to four conditions: low air exchange (4.4 h(-1)), < 2 ppb ozone; low air exchange, 6164 ppb ozone; high air exchange (8.8 h-1), < 2 ppb ozone; and high air exchange, 73-77 ppb ozone. The addition of ozone to the cabin air increased the levels of identified byproducts from similar to 70 to 130 ppb at the lower air exchange rate and from similar to 30 to 70 ppb at the higher air exchange rate. Most of the increase was attributable to acetone, nonanal, decanal, 4-oxopentanal (4-OPA), 6-methyl5-hepten-2-one (6-MHO), formic acid, and acetic acid, with 0.25-0.30 mol of quantified product volatilized per mol of ozone consumed. Several of these compounds reached levels above their reported odor thresholds. Most byproducts were derived from surface reactions with occupants and their clothing, consistent with the inference that occupants were responsible for the removal of > 55% of the ozone in the cabin. The observations made in this study have implications for other indoor settings. Whenever human beings and ozone are simultaneously present, one anticipates production of acetone, nonanal, decanal, 6-MHO, geranyl acetone, and 4-OPA. C1 Tech Univ Denmark, Int Ctr Indoor Environm & Energy, DK-2800 Lyngby, Denmark. Univ Med & Dent New Jersey, Environm & Occupat Hlth Sci Inst, Piscataway, NJ 08854 USA. Rutgers State Univ, Piscataway, NJ 08854 USA. Univ Innsbruck, Inst Ionenphys & Angew Phys, A-6020 Innsbruck, Austria. Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Indoor Environm Dept, Berkeley, CA 94720 USA. Arizona State Univ, Dept Civil & Environm Engn, Tempe, AZ 85287 USA. RP Weschler, CJ (reprint author), Tech Univ Denmark, Int Ctr Indoor Environm & Energy, DK-2800 Lyngby, Denmark. EM weschlch@umdnj.edu RI Nazaroff, William/C-4106-2008; Destaillats, Hugo/B-7936-2013; Weschler, Charles/A-9788-2009 OI Nazaroff, William/0000-0001-5645-3357; Weschler, Charles/0000-0002-9097-5850 NR 28 TC 68 Z9 70 U1 5 U2 23 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD SEP 1 PY 2007 VL 41 IS 17 BP 6177 EP 6184 DI 10.1021/es0708520 PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 207GR UT WOS:000249240100046 PM 17937299 ER PT J AU Gu, BH Brown, GM Chiang, CC AF Gu, Baohua Brown, Gilbert M. Chiang, Chen-Chou TI Treatment of perchlorate-contaminated groundwater using highly selective, regenerable ion-exchange technologies SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID DRINKING-WATER; RESINS; CHROMATOGRAPHY AB Treatment of perchlorate-contaminated water using highly selective, regenerable ion-exchange and perchlorate-destruction technologies was demonstrated at a field site in California. Four treatment and four regeneration cycles were carried out, and no significant deterioration of resin performance was noted in 2 years. The bifunctional resin (Purolite A-530E) treated about 37 000 empty bed volumes (BVs) of groundwater before a significant breakthrough of perchlorate occurred at an average flow rate of 150 gpm (or 1 BV/min) and a feed perchlorate concentration of about 860 mu g/L. Sorbed perchlorate (similar to 20 kg) was quantitatively recovered by eluting with as little as 1 BV of the FeCl3-HCl regenerant solution. The eluted ClO4 was highly concentrated in the third quarter of the first BV of the regenerant solution with a concentration up to 100 000 mg/L. This concentrated effluent greatly facilitated subsequent perchlorate destruction or recovery by precipitation as KClO4 salts. High perchlorate destruction efficiency (92-97%) was observed by reduction with FeCl2 in a thermoreactor, which enabled recycling of the FeCl3-HCl regenerant solution, thereby minimizing the need to dispose of secondary wastes containing ClO4-. This study demonstrates that a combination of novel selective, regenerable ion-exchange and perchlorate-destruction and/or recovery technologies could potentially lead to enhanced treatment efficiency and minimized secondary waste production. C1 Oak Ridge Natl Lab, Environm & Chem Sci Div, Oak Ridge, TN 37831 USA. Calgon Carbon Corp, Pittsburgh, PA 15205 USA. RP Gu, BH (reprint author), Oak Ridge Natl Lab, Environm & Chem Sci Div, Oak Ridge, TN 37831 USA. EM gub1@ornl.gov RI Gu, Baohua/B-9511-2012 OI Gu, Baohua/0000-0002-7299-2956 NR 26 TC 65 Z9 74 U1 2 U2 27 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD SEP 1 PY 2007 VL 41 IS 17 BP 6277 EP 6282 DI 10.1021/es0706910 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 207GR UT WOS:000249240100062 PM 17937315 ER PT J AU Buchanan, IS Apte, MG Mirer, A Mendell, MJ AF Buchanan, I. S. Apte, M. G. Mirer, A. Mendell, M. J. TI Outdoor ozone modifies effects of air filter medium on building-related symptoms in the base study SO EPIDEMIOLOGY LA English DT Meeting Abstract CT 19th Annual Conference of the International-Society-for-Environmental-Epidemiology CY SEP 05-09, 2007 CL Mexico City, MEXICO SP Int Soc Environm Epidemiol C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1044-3983 J9 EPIDEMIOLOGY JI Epidemiology PD SEP PY 2007 VL 18 IS 5 SU S BP S193 EP S193 PG 1 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 204BQ UT WOS:000249018300634 ER PT J AU Mendell-J, M Lei-Gomez, Q Apte-G, M AF Mendell-J, M. Lei-Gomez, Q. Apte-G, M. TI Ventilation rate and building-related symptoms in 100 US office buildings - The US EPA Base Study SO EPIDEMIOLOGY LA English DT Meeting Abstract CT 19th Annual Conference of the International-Society-for-Environmental-Epidemiology CY SEP 05-09, 2007 CL Mexico City, MEXICO SP Int Soc Environm Epidemiol C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Harvard Univ, Sch Publ Hlth, Cambridge, MA 02138 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1044-3983 J9 EPIDEMIOLOGY JI Epidemiology PD SEP PY 2007 VL 18 IS 5 SU S BP S174 EP S174 PG 1 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 204BQ UT WOS:000249018300572 ER PT J AU Maskarinec, G Carlin, L Pagano, I Yamamoto, J Shumay, D Wilkens, LR Kolonel, LN AF Maskarinec, Gertraud Carlin, Linda Pagano, Ian Yamamoto, Jennifer Shumay, Dianne Wilkens, Lynne R. Kolonel, Laurence N. TI Original reports: Lifestyle and behavior change measures - Lifestyle risk factors for chronic disease in a multiethnic population: An analysis of two prospective studies over a 20-year period SO ETHNICITY & DISEASE LA English DT Article DE risk factors; ethnicity; cancer; chronic disease; nutrition; smoking; alcohol use ID UNITED-STATES; SOCIAL-CLASS; LOS-ANGELES; ALCOHOL; CANCER; MORTALITY; ETHNICITY; OBESITY; HAWAII; COHORT AB Objective: This study investigated changes in risk factors in Hawaii over 20 years and compared health behaviors among ethnic groups with well-documented differences in disease risk. Design: Comparison of scores of a Chronic Disease Risk Index (CDRI) in the population of two large population-based cohorts. Participants: The respective sample sizes for the two cohorts were 19,319 and 97,746 persons ages >= 40 years of White, Chinese, Filipino, Japanese, and Native Hawaiian ancestry. Main Outcome Measures: The CDRI included smoking status, alcohol use, meat intake, fruit and vegetable consumption, and body mass index. Mean total and component scores were compared over time and by ethnic group after adjustment for age and education. Results: We found a reduction in overall CDRI scores, ie, improved health profiles, for both men and women over time. Men, Native Hawaiians, and Whites had higher CDRI scores than women and Japanese, Chinese, and Filipinos due to their higher scores for smoking, alcohol use, and overweight, whereas nutritional intakes were similar in all ethnic categories. Smoking, alcohol use, and overweight increased over time in both men and women, whereas dietary composition appeared to improve. Conclusions: This analysis suggests an overall reduction in modifiable dietary and lifestyle risk factors in Hawaii over time. Persistent differences by sex and ethnic category indicate that interventions to modify lifestyle factors need to tailor messages to the groups at highest risk. C1 Univ Hawaii, Canc Res Ctr Hawaii, Honolulu, HI 96813 USA. Battelle Seattle Res Ctr, Seattle, WA USA. RP Maskarinec, G (reprint author), Univ Hawaii, Canc Res Ctr Hawaii, 1236 Lauhala St, Honolulu, HI 96813 USA. EM gertraud@crch.hawaii.edu FU NCI NIH HHS [N01-PC67001] NR 42 TC 3 Z9 3 U1 1 U2 2 PU INT SOC HYPERTENSION BLACKS-ISHIB PI ATLANTA PA 100 AUBURN AVE NE STE 401, ATLANTA, GA 30303-2527 USA SN 1049-510X J9 ETHNIC DIS JI Ethn. Dis. PD FAL PY 2007 VL 17 IS 4 BP 597 EP 603 PG 7 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 233UK UT WOS:000251115600001 PM 18072366 ER PT J AU Bleyl, SB Moshrefi, A Shaw, GM Saijoh, Y Schoenwolf, GC Pennacchio, LA Slavotinek, AM AF Bleyl, S. B. Moshrefi, A. Shaw, G. M. Saijoh, Y. Schoenwolf, G. C. Pennacchio, L. A. Slavotinek, A. M. TI Candidate genes for congenital diaphragmatic hernia from animal models: sequencing of FOG2 and PDGFR alpha reveals rare variants in diaphragmatic hernia patients SO EUROPEAN JOURNAL OF HUMAN GENETICS LA English DT Article DE congenital diaphragmatic hernia; FOG2; PDGFR alpha; animal models; mutation detection ID COMPARATIVE GENOMIC HYBRIDIZATION; GASTROINTESTINAL STROMAL TUMORS; GATA TRANSCRIPTION FACTORS; FRYNS-SYNDROME; HEART MORPHOGENESIS; RECEPTOR; MUTATIONS; COFACTOR; GROWTH; REQUIREMENT AB Congenital diaphragmatic hernia (CDH) is a common, life threatening birth defect. Although there is strong evidence implicating genetic factors in its pathogenesis, few causative genes have been identified, and in isolated CDH, only one de novo, nonsense mutation has been reported in FOG2 in a female with posterior diaphragmatic eventration. We report here that the homozygous null mouse for the Pdgfr alpha gene has posterolateral diaphragmatic defects and thus is a model for human CDH. We hypothesized that mutations in this gene could cause human CDH. We sequenced PDGFR alpha and FOG2 in 96 patients with CDH, of which 53 had isolated CDH (55.2%), 36 had CDH and additional anomalies (37.5%), and 7 had CDH and known chromosome aberrations (7.3%). For FOG2, we identified novel sequence alterations predicting p. M703L and p. T843A in two patients with isolated CDH that were absent in 526 and 564 control chromosomes respectively. These altered amino acids were highly conserved. However, due to the lack of available parental DNA samples we were not able to determine if the sequence alterations were de novo. For PDGFRa, we found a single variant predicting p. L967V in a patient with CDH and multiple anomalies that was absent in 768 control chromosomes. This patient also had one cell with trisomy 15 on skin fibroblast culture, a finding of uncertain significance. Although our study identified sequence variants in FOG2 and PDGFRa, we have not definitively established the variants as mutations and we found no evidence that CDH commonly results from mutations in these genes. C1 Univ Utah, Dept Pediat, Div Genet, Salt Lake City, UT USA. Calif Birth Defects Monitoring Program, Berkeley, CA USA. Univ Utah, Dept Neurobiol & Anat, Salt Lake City, UT USA. US DOE, Joint Genome Inst, Walnut Creek, CA USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Genom Div, Berkeley, CA 94720 USA. RP Slavotinek, AM (reprint author), Univ Calif San Francisco, Dept Pediat, Div Genet, 533 Parnassus St,Room U585P, San Francisco, CA 94143 USA. EM slavotia@peds.ucsf.edu FU NHLBI NIH HHS [HL066681, 1K08HL084559]; NIDCD NIH HHS [DC04185]; NIDDK NIH HHS [DK066445, DK065941]; PHS HHS [5R03 HDO49411-02] NR 32 TC 33 Z9 34 U1 1 U2 5 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1018-4813 J9 EUR J HUM GENET JI Eur. J. Hum. Genet. PD SEP PY 2007 VL 15 IS 9 BP 950 EP 958 DI 10.1038/sj.ejhg.5201872 PG 9 WC Biochemistry & Molecular Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Genetics & Heredity GA 205WB UT WOS:000249144200008 PM 17568391 ER PT J AU Frahm, N Yusim, K Suscovich, TJ Adams, S Sidney, J Hraber, P Hewitt, HS Linde, CH Kavanagh, DG Woodberry, T Henry, LM Faircloth, K Listgarten, J Kadie, C Jojic, N Sango, K Brown, NV Pae, E Zaman, MT Bihl, F Khatri, A John, M Mallal, S Marincola, FM Walker, BD Sette, A Heckerman, D Korber, BT Brander, C AF Frahm, Nicole Yusim, Karina Suscovich, Todd J. Adams, Sharon Sidney, John Hraber, Peter Hewitt, Hannah S. Linde, Caitlyn H. Kavanagh, Daniel G. Woodberry, Tonia Henry, Leah M. Faircloth, Kellie Listgarten, Jennifer Kadie, Carl Jojic, Nebojsa Sango, Kaori Brown, Nancy V. Pae, Eunice Zaman, M. Tauheed Bihl, Florian Khatri, Ashok John, Mina Mallal, Simon Marincola, Francesco M. Walker, Bruce D. Sette, Alessandro Heckerman, David Korber, Bette T. Brander, Christian TI Extensive HLA class I allele promiscuity among viral CTL epitopes SO EUROPEAN JOURNAL OF IMMUNOLOGY LA English DT Article DE antigen; bioinformatics; CD8 T cells; HIV; immune responses ID T-CELL EPITOPES; HUMAN-IMMUNODEFICIENCY-VIRUS; LYMPHOCYTE EPITOPES; BIOINFORMATICS APPROACH; HIV POLYMORPHISMS; PEPTIDE BINDING; HEPATITIS-C; IDENTIFICATION; RECOGNITION; MOLECULES AB Promiscuous binding of T helper epitopes to MHC class 11 molecules has been well established, but few examples of promiscuous class I-restricted epitopes exist. To address the extent of promiscuity of HLA class I peptides, responses to 242 well-defined viral epitopes were tested in 100 subjects regardless of the individuals' HLA type. Surprisingly, half of all detected responses were seen in the absence of the originally reported restricting HLA class I allele, and only 3% of epitopes were recognized exclusively in the presence of their original allele. Functional assays confirmed the frequent recognition of HLA class I-restricted T cell epitopes on several alternative alleles across HLA class I supertypes and encoded on different class I loci. These data have significant implications for the understanding of MHC class I-restricted antigen presentation and vaccine development. C1 Harvard Univ, Massachusetts Gen Hosp, Sch Med, Partners AIDS Res Ctr, Charlestown, MA 02129 USA. Los Alamos Natl Lab, Los Alamos, NM USA. NIH, Ctr Clin, Bethesda, MD 20892 USA. La Jolla Inst Allergy & Immunol, La Jolla, CA USA. Microsoft Res, Redmond, WA USA. Fenway Community Hlth Ctr, Boston, MA USA. Lemuel Shattuck Hosp, Boston, MA USA. Harvard Univ, Sch Med, Massachusetts Gen Hosp, Endocrine Unit, Boston, MA 02115 USA. Royal Perth Hosp, Ctr Clin Immunol & Biomed Stat, Perth, WA, Australia. Murdoch Univ, Perth, WA, Australia. Harvard Univ, Sch Med, Massachusetts Gen Hosp, Howard Hughes Med Inst, Boston, MA 02115 USA. Harvard Univ, Sch Med, Div AIDS, Boston, MA USA. Santa Fe Inst, Santa Fe, NM 87501 USA. RP Brander, C (reprint author), Harvard Univ, Massachusetts Gen Hosp, Sch Med, Partners AIDS Res Ctr, 149 13th St,Room 5239, Charlestown, MA 02129 USA. EM cbrander@partners.org OI Brander, Christian/0000-0002-0548-5778; Korber, Bette/0000-0002-2026-5757; Hraber, Peter/0000-0002-2920-4897 FU NIAID NIH HHS [F32 AI058457, R01 AI067077-01, R01 AI067077-02, R01 AI067077-03, R21 AI055421, R21-AI-055421-01-A1]; PHS HHS [N01-AL-15422, R01-A1-067077] NR 58 TC 77 Z9 78 U1 0 U2 3 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0014-2980 J9 EUR J IMMUNOL JI Eur. J. Immunol. PD SEP PY 2007 VL 37 IS 9 BP 2419 EP 2433 DI 10.1002/eji.200737365 PG 15 WC Immunology SC Immunology GA 214MV UT WOS:000249743200012 PM 17705138 ER PT J AU Coker, VS Pearce, CI Lang, C van der Laan, G Pattrick, RAD Telling, ND Schuler, D Arenholz, E Lloyd, JR AF Coker, Victoria S. Pearce, Carolyn I. Lang, Claus van der Laan, Gerrit Pattrick, Richard A. D. Telling, Neil D. Schueler, Dirk Arenholz, Elke Lloyd, Jonathan R. TI Cation site occupancy of biogenic magnetite compared to polygenic ferrite spinels determined by X-ray magnetic circular dichroism SO EUROPEAN JOURNAL OF MINERALOGY LA English DT Article DE X-ray magnetic circular dichroism; XMCD; nanoparticles; metal reduction; Fe(III) reduction; Geobacter; biomineralogy; biogenic magnetite ID MAGNETOTACTIC BACTERIA; DISSIMILATORY REDUCTION; MICROBIAL REDUCTION; MAGNETOSPIRILLUM-GRYPHISWALDENSE; GEOBACTER-SULFURREDUCENS; MINERALIZATION PATHWAYS; REDUCING MICROORGANISM; MAGNETOSOME MEMBRANE; SP-NOV; IRON AB Ferrite spinels, especially magnetite (Fe3O4), can be formed either by geological, biological or chemical processes leading to chemically similar phases that show different physical characteristics. We compare, for the first time, magnetite produced by these three different methods using X-ray magnetic circular dichroism (XMCD), a synchrotron radiation based technique able to determine the site occupancy of Fe cations in the ferrite spinels. Extracellular nanoscale magnetite produced by different Fe(Ill)reducing bacteria was shown to have different degrees of stoichiometry depending on the bacteria and the method of formation, but all were oxygen deficient due to formation under anoxic conditions. Intracellular nano-magnetite synthesized in the magnetosomes of magnetotactic bacteria was found to have a Fe cation site occupancy ratio most similar to stoichiometric magnetite, possibly due to the tight physiological controls exerted by the magnetosome membrane. Chemically-synthesised nano-magnetite and bulk magnetite produced as a result of geological processes were both found to be cation deficient with a composition between magnetite and maghemite (oxidised magnetite). C1 [Coker, Victoria S.; Pearce, Carolyn I.; van der Laan, Gerrit; Pattrick, Richard A. D.; Lloyd, Jonathan R.] Univ Manchester, Sch Earth Atmospher & Environm Sci, Manchester M13 9PL, Lancs, England. [Coker, Victoria S.; Pearce, Carolyn I.; van der Laan, Gerrit; Pattrick, Richard A. D.; Lloyd, Jonathan R.] Univ Manchester, Williamson Res Ctr Mol Environm Sci, Manchester M13 9PL, Lancs, England. [van der Laan, Gerrit; Telling, Neil D.] SERC, Daresbury Lab, Magnet Spect Grp, Warrington WA4 4AD, Cheshire, England. [Lang, Claus; Schueler, Dirk] Max Planck Inst Marine Microbiol, D-28359 Bremen, Germany. [Arenholz, Elke] Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Coker, VS (reprint author), Univ Manchester, Sch Earth Atmospher & Environm Sci, Manchester M13 9PL, Lancs, England. EM vicky.coker@manchester.ac.uk RI Coker, Victoria/B-4181-2012; Lang, Claus /E-6883-2015; van der Laan, Gerrit/Q-1662-2015 OI Lang, Claus /0000-0003-2767-3857; van der Laan, Gerrit/0000-0001-6852-2495 NR 54 TC 33 Z9 35 U1 0 U2 14 PU E SCHWEIZERBARTSCHE VERLAGS PI STUTTGART PA NAEGELE U OBERMILLER, SCIENCE PUBLISHERS, JOHANNESSTRASSE 3A, D 70176 STUTTGART, GERMANY SN 0935-1221 J9 EUR J MINERAL JI Eur. J. Mineral. PD SEP-OCT PY 2007 VL 19 IS 5 BP 707 EP 716 DI 10.1127/0935-1221/2007/0019-1758 PG 10 WC Mineralogy SC Mineralogy GA 246IJ UT WOS:000252000400010 ER PT J AU Jimenez-Lopez, C Rodriguez-Navarro, A Perez-Gonzalez, T Carrillo-Rosua, J Boyce, AE Romanek, CS AF Jimenez-Lopez, Concepcion Rodriguez-Navarro, Alejandro Perez-Gonzalez, Teresa Carrillo-Rosua, Javier Boyce, Adrian E. Romanek, Christopher S. TI New method for separation of magnetite from rock samples for oxygen isotope analysis SO EUROPEAN JOURNAL OF MINERALOGY LA English DT Article DE magnetite; pyrrhotite; oxygen isotope; mineral separation ID PYRRHOTITE; OXIDES; IRON; FRACTIONATION; SILICATES; SEDIMENTS; MINERALS; ALH84001; GRANITE; ORIGIN AB A new procedure is described to separate magnetite from milligram sized samples of crushed rock for oxygen isotope analysis. This method is based on magnetic separation of magnetite after heating the mixture to a temperature that exceeds the Curie point for other magnetic minerals in a sample. The relatively low temperature of this procedure (350 degrees C) does not induce any reaction between magnetic mineral nor does it alter the isotope composition of magnetite. This procedure was tested on samples containing known percentages of magnetite and pyrrhotite. The percentage of magnetite in a sample was increased by 10-20% through successive enrichment cycles until a pure magnetite separate was achieved. The separation should be performed before measuring the oxygen isotope composition of the magnetic fraction of a rock sample by laser fluorination, because the presence of contaminating phases such as pyrrhotite may cause unwanted isotope partitioning of the oxygen released during fluorination. Our data show that contamination of a magnetite sample, even with a non O-bearing phase, can lead to systematically misleading O isotope data in a standard total laser fluorination system. Enrichment of the apparent magnetite value is indicated, possibly as a result of the formation of an O-S-bearing phase. C1 [Rodriguez-Navarro, Alejandro] Univ Granada, Dept Mineral & Petrol, E-18071 Granada, Spain. [Jimenez-Lopez, Concepcion; Perez-Gonzalez, Teresa] Univ Granada, Dept Microbiol, E-18071 Granada, Spain. [Carrillo-Rosua, Javier; Boyce, Adrian E.] Scottish Univ Environm Res Ctr, Glasgow G75 0QF, Lanark, Scotland. [Romanek, Christopher S.] Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29808 USA. [Romanek, Christopher S.] Univ Georgia, Dept Geol, Aiken, SC 29808 USA. RP Rodriguez-Navarro, A (reprint author), Univ Granada, Dept Mineral & Petrol, Avda Fuentenueva S-N, E-18071 Granada, Spain. EM anava@ugr.es RI Carrillo-Rosua, Javier/L-8157-2014 OI Carrillo-Rosua, Javier/0000-0003-2889-3966 NR 33 TC 1 Z9 1 U1 1 U2 7 PU E SCHWEIZERBARTSCHE VERLAGS PI STUTTGART PA NAEGELE U OBERMILLER, SCIENCE PUBLISHERS, JOHANNESSTRASSE 3A, D 70176 STUTTGART, GERMANY SN 0935-1221 J9 EUR J MINERAL JI Eur. J. Mineral. PD SEP-OCT PY 2007 VL 19 IS 5 BP 717 EP 722 DI 10.1127/0935-1221/2007/0019-1761 PG 6 WC Mineralogy SC Mineralogy GA 246IJ UT WOS:000252000400011 ER PT J AU Mosconi, L Tsui, WH Rusinek, H De Santi, S Li, Y Wang, GJ Pupi, A Fowler, J de Leon, MJ AF Mosconi, Lisa Tsui, Wai H. Rusinek, Henry De Santi, Susan Li, Yi Wang, Gene-Jack Pupi, Alberto Fowler, Joanna de Leon, Mony J. TI Quantitation, regional vulnerability, and kinetic modeling of brain glucose metabolism in mild Alzheimer's disease SO EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING LA English DT Article DE Alzheimer's disease; metabolic rate of glucose; dynamic FDG PET imaging; kinetic rate constants; hippocampus; posterior cingulate cortex ID COGNITIVE IMPAIRMENT; FDG-PET; DEMENTIA; TRANSPORT; MRI; MCI; HYPOMETABOLISM; DETERIORATION; TOMOGRAPHY; PREDICTION AB Purpose To examine CMRglc measures and corresponding glucose transport (K-1 and k(2)) and phosphorylation (k(3)) rates in the medial temporal lobe (MTL, comprising the hippocampus and amygdala) and posterior cingulate cortex (PCC) in mild Alzheimer's disease (AD). Methods Dynamic FDG PET with arterial blood sampling was performed in seven mild AD patients (age 68 +/- 8 years, four females, median MMSE 23) and six normal (NL) elderly (age 69 +/- 9 years, three females, median MMSE 30). Absolute CMRglc (mu mol/100 g/min) was calculated from MRI-defined regions of interest using multiparametric analysis with individually fitted kinetic rate constants, Gjedde-Patlak plot, and Sokoloff's autoradiographic method with population-based rate constants. Relative ROI/pons CMRglc (unitless) was also examined. Results With all methods, AD patients showed significant CMRglc reductions in the hippocampus and PCC, and a trend towards reduced parietotemporal CMRglc, as compared with NL. Significant k(3) reductions were found in the hippocampus, PCC and amygdala. K-1 reductions were restricted to the hippocampus. Relative CMRglc had the largest effect sizes in separating AD from NL. However, the magnitude of CMRglc reductions was 1.2- to 1.9-fold greater with absolute than with relative measures. Conclusion CMRglc reductions are most prominent in the MTL and PCC in mild AD, as detected with both absolute and relative CMRglc measures. Results are discussed in terms of clinical and pharmaceutical applicability. C1 NYU, Sch Med, Dept Psychiat, Ctr Brain Hlth, New York, NY 10016 USA. Nathan S Kline Inst Psychiat Res, Orangeburg, NY 10962 USA. Univ Florence, Dept Clin Pathophysiol, Nucl Med Unit, Florence, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Mosconi, L (reprint author), NYU, Sch Med, Dept Psychiat, Ctr Brain Hlth, MHL 400,560 1st Ave, New York, NY 10016 USA. EM lisa.mosconi@med.nyu.edu OI li, yi/0000-0002-3875-3513; de Leon, Mony/0000-0003-2245-4380; Pupi, Alberto/0000-0002-4322-4704 FU NCRR NIH HHS [M01RR0096]; NIA NIH HHS [AG022374, AG08051, AG12101, AG13616] NR 34 TC 22 Z9 26 U1 1 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1619-7070 J9 EUR J NUCL MED MOL I JI Eur. J. Nucl. Med. Mol. Imaging PD SEP PY 2007 VL 34 IS 9 BP 1467 EP 1479 DI 10.1007/s00259-007-0406-5 PG 13 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 203LG UT WOS:000248975500019 PM 17406865 ER PT J AU Ukai, M Ajimura, S Akikawa, H Alburger, DE Banu, A Chen, RE Franklin, GB Franz, J Hashimoto, O Hayakawa, T Hotchi, H Imai, K Kishimoto, T May, M Millener, DJ Minami, S Miura, Y Miyoshi, T Mizunuma, K Nagae, T Nakazawa, SN Nakazawa, K Okayasu, Y Pile, P Quinn, BP Rusek, A Sato, Y Sutter, R Takahashi, H Tang, L Tamura, H Tanida, K Yuan, L Zhou, SH AF Ukai, M. Ajimura, S. Akikawa, H. Alburger, D. E. Banu, A. Chen, R. E. Franklin, G. B. Franz, J. Hashimoto, O. Hayakawa, T. Hotchi, H. Imai, K. Kishimoto, T. May, M. Millener, D. J. Minami, S. Miura, Y. Miyoshi, T. Mizunuma, K. Nagae, T. Nakazawa, S. N. Nakazawa, K. Okayasu, Y. Pile, P. Quinn, B. P. Rusek, A. Sato, Y. Sutter, R. Takahashi, H. Tang, L. Tamura, H. Tanida, K. Yuan, L. Zhou, S. H. TI Observation of the 7 MeV excited spin-flip and non-spin-flip partners in O-16(Lambda) by gamma -ray spectroscopy SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article; Proceedings Paper CT 9th International Conference on Hypernuclear and Strange Particle Physics CY OCT 10-14, 2006 CL Johannes-Gutenberg Univ, Mainz, GERMANY SP Gesell Schwerionenforsch, Inst Kernphys HO Johannes-Gutenberg Univ ID LAMBDA-HYPERNUCLEI AB We have observed three gamma-ray transitions in O-16(Lambda) from both 7MeV excited spin-flip and non-spin-flip partners (2(-), 1(2)(-) to the ground-state doublet (1(1)(-), 0(-) via the O-16(K-,pi(-)) reaction. The 7MeV excitation energies of the spin-doublet members (2(-), 1(2)(-) were determined to be 6784 +/- 4 +/- 4 keV and 6562 +/- 1 +/- 2 keV, respectively, and thus the spacing was obtained to be 222 +/- 4 +/- 5 keV. This is the first observation of the spin-flip state directly populated by the (K-,pi(-) reaction. Moreover, such directly populated spin-flip and non-spin-flip partners were resolved for the first time. C1 Gifu Univ, Dept Phys, Gifu 5011193, Japan. Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. Osaka Univ, Dept Phys, Toyonaka, Osaka 5600043, Japan. Kyoto Univ, Dept Phys, Kyoto 6068502, Japan. Brookhaven Natl Lab, Upton, NY 11973 USA. GSI Darmstadt, D-64291 Darmstadt, Germany. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Freiburg, Dept Phys, D-79104 Freiburg, Germany. Natl Lab High Energy Phys, KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki 3050801, Japan. Hampton Univ, Dept Phys, Hampton, VA 23668 USA. RIKEN, Wako, Saitama 3510198, Japan. CIAE, Dept Phys, Beijing 102413, Peoples R China. RP Ukai, M (reprint author), Gifu Univ, Dept Phys, Gifu 5011193, Japan. EM m-ukai@phys.ed.gifu-u.ac.jp RI Franklin, Gregg/N-7743-2014 OI Franklin, Gregg/0000-0003-4176-1378 NR 16 TC 1 Z9 1 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1434-6001 J9 EUR PHYS J A JI Eur. Phys. J. A PD SEP PY 2007 VL 33 IS 3 BP 247 EP 250 DI 10.1140/epja/i2007-10473-7 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 209TA UT WOS:000249409700003 ER PT J AU Watanabe, T Ahn, JK Akikawa, H Aoki, S Arai, K Bahk, SY Baik, KM Bassalleck, B Chung, JH Chung, MS Davis, DH Fukuda, T Hayata, H Hoshino, K Ichikawa, A Ieiri, M Imai, K Iwata, YH Iwata, YS Kakita, Y Kanda, H Kaneko, M Kawai, T Kawasaki, M Kim, CO Kim, JY Kim, SJ Kim, SH Kondo, Y Kouketsu, T Lee, YL McNabb, JWC Mitsuhara, M Nagase, Y Nagoshi, C Nakazawa, K Noumi, H Ogawa, S Okabe, H Oyama, K Park, HM Park, IG Parker, J Ra, YS Rhee, JT Rusek, A Shibuya, H Sim, KS Saha, PK Seki, D Sekimoto, M Song, JS Takahashi, H Takahashi, T Takeutchi, F Tanaka, H Tanida, K Tojo, J Torii, H Torikai, S Tsunemi, T Tovee, DN Ushida, N Yamamoto, K Yasuda, N Yang, JT Yoon, CJ Yoon, CS Yosoi, M Yoshida, T Zhu, L AF Watanabe, T. Ahn, J. K. Akikawa, H. Aoki, S. Arai, K. Bahk, S. Y. Baik, K. M. Bassalleck, B. Chung, J. H. Chung, M. S. Davis, D. H. Fukuda, T. Hayata, H. Hoshino, K. Ichikawa, A. Ieiri, M. Imai, K. Iwata, Y. H. Iwata, Y. S. Kakita, Y. Kanda, H. Kaneko, M. Kawai, T. Kawasaki, M. Kim, C. O. Kim, J. Y. Kim, S. J. Kim, S. H. Kondo, Y. Kouketsu, T. Lee, Y. L. McNabb, J. W. C. Mitsuhara, M. Nagase, Y. Nagoshi, C. Nakazawa, K. Noumi, H. Ogawa, S. Okabe, H. Oyama, K. Park, H. M. Park, I. G. Parker, J. Ra, Y. S. Rhee, J. T. Rusek, A. Shibuya, H. Sim, K. S. Saha, P. K. Seki, D. Sekimoto, M. Song, J. S. Takahashi, H. Takahashi, T. Takeutchi, F. Tanaka, H. Tanida, K. Tojo, J. Torii, H. Torikai, S. Tsunemi, T. Tovee, D. N. Ushida, N. Yamamoto, K. Yasuda, N. Yang, J. T. Yoon, C. J. Yoon, C. S. Yosoi, M. Yoshida, T. Zhu, L. TI First observation of the Sigma N decay of the S =-2 system SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article; Proceedings Paper CT 9th International Conference on Hypernuclear and Strange Particle Physics CY OCT 10-14, 2006 CL Johannes-Gutenberg Univ, Mainz, GERMANY SP Gesell Schwerionenforsch mbH, Inst Kernphys HO Johannes-Gutenberg Univ ID H-DIBARYON; SEARCH AB An event emitting a Sigma(-)-hyperon from a Xi(-)-hyperon nuclear capture at rest has been observed in a hybrid-emulsion experiment. The event has been analyzed as the first observation of the weak decay of the S = - 2 system. C1 Gifu Univ, Dept Phys, Gifu, Japan. Kyoto Univ, Dept Phys, Kyoto, Japan. Kobe Univ, Fac Human Dev, Kobe, Hyogo, Japan. Wonkwang Univ, Iri, South Korea. Korea Univ, Dept Phys, Seoul, South Korea. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. UCL, Dept Phys & Astron, London, England. Nagoya Univ, Dept Phys, Nagoya, Aichi, Japan. Konkuk Univ, Inst Adv Phys, Seoul, South Korea. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Osaka Prefectural Educ Ctr, Osaka, Japan. Brookhaven Natl Lab, Upton, NY 11973 USA. Tohoku Univ, Dept Phys, Sendai, Miyagi 980, Japan. Univ Tokyo, Dept Phys, Tokyo 113, Japan. Natl Inst Radiol Sci, Chiba 260, Japan. Osaka City Univ, Dept Phys, Osaka, Japan. RP Watanabe, T (reprint author), Gifu Univ, Dept Phys, Gifu, Japan. RI Ahn, Jung Keun/C-1293-2008; Aoki, Shigeki/L-6044-2015 NR 11 TC 7 Z9 7 U1 0 U2 6 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6001 EI 1434-601X J9 EUR PHYS J A JI Eur. Phys. J. A PD SEP PY 2007 VL 33 IS 3 BP 265 EP 268 DI 10.1140/epja/i2007-10465-7 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 209TA UT WOS:000249409700007 ER PT J AU Kurpeta, J Urban, W Droste, C Plochocki, A Rohozinski, SG Rzaca-Urban, T Morek, T Prochniak, L Starosta, K Aysto, J Penttila, H Durell, JL Smith, AG Lhersonneau, G Ahmad, I AF Kurpeta, J. Urban, W. Droste, Ch. Plochocki, A. Rohozinski, S. G. Rzaca-Urban, T. Morek, T. Prochniak, L. Starosta, K. Aysto, J. Penttilae, H. Durell, J. L. Smith, A. G. Lhersonneau, G. Ahmad, I. TI Low-spin structure of Ru-113 and Rh-113 SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID HALF-LIFE PREDICTIONS; PALLADIUM ISOTOPES; RU ISOTOPES; PD ISOTOPES; BETA-DECAY; NEUTRON; FISSION; NUCLEUS; STATES; TRIAXIALITY AB The Ru-113 and Rh-113 nuclei, produced in the spontaneous fission of Cm-248 and in proton-induced fission of U-238; were studied by means of prompt gamma spectroscopy using the EUROGAM 2 array of Anti-Compton spectrometers and the IGISOL mass separator, respectively. For the 0.5 s isomer, found in (RU)-R-113 in our recent study we propose the 7/2- [523] configuration. The present data indicate spin and parity 1/2(+) for the ground state in Ru-113. This and some new data on the excited levels in Rh-113 allows reinterpretation and a better Understanding of the beta(-) decay scheme of Ru-113. The properties of Ru-113 were studied in the frame of the Core-Quasiparticle Coupling model, which has well reproduced the experimental data. C1 Univ Warsaw, Fac Phys, PL-00681 Warsaw, Poland. Marie Curie Sklodowska Univ, Inst Phys, PL-20031 Lublin, Poland. Michigan State Univ, Cyclotron Lab, NSCL, E Lansing, MI 48824 USA. Univ Jyvaskyla, Dept Phys, FIN-40351 Jyvaskyla, Finland. Univ Manchester, Dept Phys & Astron, Schuster Lab, Manchester M13 9PL, Lancs, England. Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Legnaro, Italy. Argonne Natl Lab, Argonne, IL 60439 USA. RP Kurpeta, J (reprint author), Univ Warsaw, Fac Phys, Ul Hoza 69, PL-00681 Warsaw, Poland. EM jkurpeta@mimuw.edu.pl RI Penttila, Heikki/A-4420-2013; Prochniak, Leszek/B-6943-2013 OI Prochniak, Leszek/0000-0002-6577-6438 NR 42 TC 12 Z9 12 U1 1 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1434-6001 J9 EUR PHYS J A JI Eur. Phys. J. A PD SEP PY 2007 VL 33 IS 4 BP 307 EP 316 DI 10.1140/epia/i2006-10464-2 PG 10 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 225ZG UT WOS:000250556300002 ER PT J AU Catanesi, MG Radicioni, E Edgecock, R Ellis, M Robbins, S Soler, FJP Gossling, C Bunyatov, S Chelkov, G Dedovitch, D Gostkin, M Guskov, A Khartchenko, D Krasnoperov, A Kroumchtein, Z Nefedov, Y Popov, B Serdiouk, V Tereshchenko, V Zhemchugov, A Di Capua, E Vidal-Sitjes, G Artamonov, A Arce, P Giani, S Gilardoni, S Gorbunov, P Grant, A Grossheim, A Gruber, P Ivanchenko, V Kayis-Topaksu, A Panman, J Papadopoulos, I Pasternak, J Tcherniaev, E Tsukerman, I Veenhof, R Wiebusch, C Zucchelli, P Blondel, A Borghi, S Campanelli, M Morone, MC Prior, G Schroeter, R Engel, R Meurer, C Kato, I Gastaldi, U Mills, GB Graulich, JS Gregoire, G Bonesini, M De Min, A Ferri, F Paganoni, M Paleari, F Kirsanov, M Bagulya, A Grichine, V Polukhina, N Palladino, V Coney, L Schmitz, D Barr, G De Santo, A Pattison, C Zuber, K Bobisut, F Gibin, D Guglielmi, A Mezzetto, M Dumarchez, J Vannucci, F Ammosov, V Koreshev, V Semak, A Zaets, V Dore, U Orestano, D Pastore, F Tonazzo, A Tortora, L Booth, C Buttar, C Hodgson, P Howlett, L Bogomilov, M Chizhov, M Kolev, D Tsenov, R Piperov, S Temnikov, P Apollonio, M Chimenti, P Giannini, G Santin, G Burguet-Castell, J Cervera-Villanueva, A Gomez-Cadenas, JJ Martin-Albo, J Novella, P Sorel, M Tornero, A AF Catanesi, M. G. Radicioni, E. Edgecock, R. Ellis, M. Robbins, S. Soler, F. J. P. Goessling, C. Bunyatov, S. Chelkov, G. Dedovitch, D. Gostkin, M. Guskov, A. Khartchenko, D. Krasnoperov, A. Kroumchtein, Z. Nefedov, Y. Popov, B. Serdiouk, V. Tereshchenko, V. Zhemchugov, A. Di Capua, E. Vidal-Sitjes, G. Artamonov, A. Arce, P. Giani, S. Gilardoni, S. Gorbunov, P. Grant, A. Grossheim, A. Gruber, P. Ivanchenko, V. Kayis-Topaksu, A. Panman, J. Papadopoulos, I. Pasternak, J. Tcherniaev, E. Tsukerman, I. Veenhof, R. Wiebusch, C. Zucchelli, P. Blondel, A. Borghi, S. Campanelli, M. Morone, M. C. Prior, G. Schroeter, R. Engel, R. Meurer, C. Kato, I. Gastaldi, U. Mills, G. B. Graulich, J. S. Gregoire, G. Bonesini, M. De Min, A. Ferri, F. Paganoni, M. Paleari, F. Kirsanov, M. Bagulya, A. Grichine, V. Polukhina, N. Palladino, V. Coney, L. Schmitz, D. Barr, G. De Santo, A. Pattison, C. Zuber, K. Bobisut, F. Gibin, D. Guglielmi, A. Mezzetto, M. Dumarchez, J. Vannucci, F. Ammosov, V. Koreshev, V. Semak, A. Zaets, V. Dore, U. Orestano, D. Pastore, F. Tonazzo, A. Tortora, L. Booth, C. Buttar, C. Hodgson, P. Howlett, L. Bogomilov, M. Chizhov, M. Kolev, D. Tsenov, R. Piperov, S. Temnikov, P. Apollonio, M. Chimenti, P. Giannini, G. Santin, G. Burguet-Castell, J. Cervera-Villanueva, A. Gomez-Cadenas, J. J. Martin-Albo, J. Novella, P. Sorel, M. Tornero, A. TI Measurement of the production cross-section of positive pions in the collision of 8.9 GeV/c protons on beryllium SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID HARP; DETECTOR AB The double-differential production cross-section of positive pions, d(2)sigma(pi+)/dpd Omega, measured in the HARP experiment is presented. The incident particles are 8.9 GeV/c protons directed onto a beryllium target with a thickness of 5% of a nuclear interaction length. The measured cross-section has a direct impact on the prediction of neutrino fluxes for the MiniBooNE and SciBooNE experiments at Fermilab. After cuts, 13 million protons on target produced about 96000 reconstructed secondary tracks which were used in this analysis. Cross-section results are presented in the kinematic range 0.75 GeV/c <= p(pi)<= 6.5 GeV/c and 30 mrad <=theta(pi)<= 210 mrad in the laboratory frame. C1 Univ Bari, Bari, Italy. Sezione Ist Nazl Fis Nucl, Bari, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Dortmund, Inst Phys, D-4600 Dortmund, Germany. Joint Inst Nucl Res Dubna, Dubna, Russia. Univ Bari, Ferrara, Italy. Sezione Ist Nazl Fis Nucl, Bari, Italy. CERN, Geneva, Switzerland. Univ Geneva, Inst Phys, Geneva, Switzerland. Kyoto Univ, Kyoto, Japan. Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Legnaro, Italy. Los Alamos Natl Lab, Los Alamos, NM USA. UCL, Inst Phys Nucl, Louvain, Belgium. Univ Milano Bicocca, Milan, Italy. Sez INFN Milano Bicocca, Milan, Italy. Nucl Res Inst, Moscow, Russia. Russian Acad Sci, PN Lebedev Phys Inst, FIAN, Moscow, Russia. Univ Naples Federico II, Naples, Italy. Sezione Ist Nazl Fis Nucl, Naples, Italy. Columbia Univ, New York, NY USA. Univ Oxford, Nucl & Astrophys Lab, Oxford, England. Univ Padua, Padua, Italy. Sezione Ist Nazl Fis Nucl, Padua, Italy. Univ Paris 06, LPNHE, Paris, France. Univ Paris 07, LPNHE, Paris, France. Inst High Energy Phys, Protvino, Russia. Univ Roma La Sapienza, Rome, Italy. Sez INFN Roma 1, Rome, Italy. Univ Rome, Rome, Italy. Sez INFN Roma III, Rome, Italy. Univ Sheffield, Dept Phys, Sheffield, S Yorkshire, England. Sofia Univ St Kliment Ohridski, Fac Phys, Sofia, Bulgaria. Bulgarian Acad Sci, Inst Nucl Res & Nucl Energy, Sofia, Bulgaria. Univ Trieste, Trieste, Italy. Sezione Ist Nazl Fis Nucl, Trieste, Italy. CSIC, IFIC, Inst Fis Corpuscular, Valencia, Spain. Univ Valencia, Valencia, Spain. FNAL, Batavia, IL USA. Codian Ltd, Slough, Berks, England. Univ Glasgow, Glasgow, Lanark, Scotland. Univ London Imperial Coll Sci Technol & Med, London, England. Univ Cantabria, Inst Fis Cantabria, E-39005 Santander, Spain. SpinX Technol, Geneva, Switzerland. TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ St Gallen, St Gallen, Switzerland. Moscow MV Lomonosov State Univ, Moscow, Russia. Cukurova Univ, Adana, Turkey. Rhein Westfal TH Aachen, Phys Inst B 3, Aachen, Germany. Ist Nazl Fis Nucl, Sez Ferrara, Ferrara, Italy. Univ Roma Tor Vergata, Rome, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Geneva, Sect Phys, Geneva, Switzerland. Univ London, London, England. Univ Sussex, Brighton, E Sussex, England. ESA, ESTEC, Noordwijk, Netherlands. RP Catanesi, MG (reprint author), Univ Bari, Bari, Italy. EM gomez@mail.cern.ch RI Wiebusch, Christopher/G-6490-2012; Prior, Gersende/I-8191-2013; Bagulya, Alexander/D-4273-2014; Novella, Pau/K-2845-2014; Gomez Cadenas, Juan Jose/L-2003-2014; Grichine, Vladimir/M-8526-2015; Polukhina, Natalia/E-1610-2014; Arce, Pedro/L-1268-2014; Soler, Paul/E-8464-2011; Tcherniaev, Evgueni/G-3453-2016; Graulich, Jean-Sebastien/B-4806-2009; Buttar, Craig/D-3706-2011; Chimenti, Pietro/F-9898-2012; Paganoni, Marco/A-4235-2016; Morone, Maria Cristina/P-4407-2016; Temnikov, Petar/L-6999-2016; Booth, Christopher/B-5263-2016; OI Wiebusch, Christopher/0000-0002-6418-3008; Novella, Pau/0000-0002-0923-3172; Gomez Cadenas, Juan Jose/0000-0002-8224-7714; Arce, Pedro/0000-0003-3009-0484; Soler, Paul/0000-0002-4893-3729; Tcherniaev, Evgueni/0000-0002-3685-0635; Chimenti, Pietro/0000-0002-9755-5066; Paganoni, Marco/0000-0003-2461-275X; Morone, Maria Cristina/0000-0002-0200-0632; Temnikov, Petar/0000-0002-9559-3384; Prior, Gersende/0000-0002-6058-1420; Booth, Christopher/0000-0002-6051-2847; DE MIN, ALBERTO/0000-0002-8130-9389; Sorel, Michel/0000-0003-2141-9508; Martin-Albo, Justo/0000-0002-7318-1469; Schmitz, David/0000-0003-2165-7389 NR 16 TC 70 Z9 70 U1 0 U2 3 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6044 EI 1434-6052 J9 EUR PHYS J C JI Eur. Phys. J. C PD SEP PY 2007 VL 52 IS 1 BP 29 EP 53 DI 10.1140/epjc/s10052-007-0382-8 PG 25 WC Physics, Particles & Fields SC Physics GA 204CD UT WOS:000249019600003 ER PT J AU Skands, P Wicke, D AF Skands, P. Wicke, D. TI Non-perturbative QCD effects and the top mass at the Tevatron SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID SOFT COLOR INTERACTIONS; PAIR PRODUCTION; RECONNECTION; FRAGMENTATION; EVENTS; MODEL; COLLISIONS; FERMILAB AB We present a new, universally applicable toy model of colour reconnections in hadronic final states. The model is based on hadronising strings and has one free parameter. We next present an implementation of this model in the PYTHIA event generator and provide several parameter sets ('tunes'), constrained by fits to Tevatron minimum-bias data. Finally, we consider the sensitivity of a simplified top mass analysis to these effects, in exclusive semi-leptonic top events at the Tevatron. A first attempt at isolating the genuine non-perturbative effects gives an estimate of order delta m(top) similar to +/- 0.5 GeV from non-perturbative uncertainties, and a further delta m(top) similar to +/- 1 GeV from shower effects. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Berg Univ Gesamthsch Wuppertal, D-42097 Wuppertal, Germany. RP Skands, P (reprint author), Fermilab Natl Accelerator Lab, POB 500,MS106, Batavia, IL 60510 USA. EM skands@fnal.gov; Daniel.Wicke@physik.uni-wuppertal.de OI Skands, Peter/0000-0003-0024-3822 NR 54 TC 113 Z9 113 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1434-6044 J9 EUR PHYS J C JI Eur. Phys. J. C PD SEP PY 2007 VL 52 IS 1 BP 133 EP 140 DI 10.1140/epjc/s10052-007-0352-1 PG 8 WC Physics, Particles & Fields SC Physics GA 204CD UT WOS:000249019600010 ER PT J AU Castorina, P Kharzeev, D Satz, H AF Castorina, P. Kharzeev, D. Satz, H. TI Thermal hadronization and hawking-unruh radiation in QCD SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID STATISTICAL BOOTSTRAP MODEL; BROKEN SCALE INVARIANCE; HEAVY-ION COLLISIONS; BLACK-HOLES; HADRON-PRODUCTION; BACKGROUND FIELD; GAUGE THEORIES; FLUX TUBES; TEMPERATURE; THERMODYNAMICS AB We conjecture that, because of color confinement, the physical vacuum forms an event horizon for quarks and gluons, which can be crossed only by quantum tunneling, i.e., through the QCD counterpart of Hawking radiation at black holes. Since such radiation cannot transmit information to the outside, it must be thermal, of a temperature determined by the chromodynamic force at the confinement surface, and it must maintain color neutrality. We explore the possibility that the resulting process provides a common mechanism for thermal hadron production in high energy interactions, from e(+)e(-) annihilation to heavy ion collisions. C1 Univ Catania, Dipartmento Fis, I-95123 Catania, Italy. Ist Nazl Fis Nucl, Sez Catania, I-95123 Catania, Italy. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Bielefeld, Fac Phys, D-33501 Bielefeld, Germany. RP Castorina, P (reprint author), Univ Catania, Dipartmento Fis, Vis Santa Sofia 64, I-95123 Catania, Italy. EM kharzeev@bnl.gov OI Castorina, Paolo/0000-0002-5617-8102 NR 67 TC 83 Z9 84 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1434-6044 J9 EUR PHYS J C JI Eur. Phys. J. C PD SEP PY 2007 VL 52 IS 1 BP 187 EP 201 DI 10.1140/epjc/s10052-007-0368-6 PG 15 WC Physics, Particles & Fields SC Physics GA 204CD UT WOS:000249019600015 ER PT J AU Bostwick, A Ohta, T McChesney, JL Seyller, T Horn, K Rotenberg, E AF Bostwick, A. Ohta, T. McChesney, J. L. Seyller, T. Horn, K. Rotenberg, E. TI Band structure and many body effects in graphene SO EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS LA English DT Article; Proceedings Paper CT Graphene Week 2006 International Conference CY 2006 CL Dresden, GERMANY SP Phys Complex Syst ID ANGLE-RESOLVED PHOTOEMISSION; WALLED CARBON NANOTUBES; SURFACE-STATE; ELECTRON-GAS; GRAPHITE; SUPERCONDUCTIVITY; ENERGY; LIFETIME; PHASE; MODEL AB We have determined the electronic bandstructure of clean and potassium-doped single layer graphene, and fitted the graphene pi bands to a one- and three-near-neighbor tight binding model. We characterized the quasi-particle dynamics using angle resolved photoemission spectroscopy. The dynamics reflect the interaction between holes and collective excitations, namely plasmons, phonons, and electron-hole pairs. Taking the topology of the bands around the Dirac energy for n-doped graphene into account, we compute the contribution to the scattering lifetimes due to electron-plasmon and electron phonon coupling. C1 EO Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA. Max Planck Gesell, Fritz Haber Inst, Dept Mol Phys, D-14195 Berlin, Germany. Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. Univ Erlangen Nurnberg, Lehrstuhl Tech Phys, Inst Phys Kondensierten Mat, D-91058 Erlangen, Germany. RP Bostwick, A (reprint author), EO Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA. EM erotenberg@lbl.gov RI Rotenberg, Eli/B-3700-2009; Seyller, Thomas/F-8410-2011; Bostwick, Aaron/E-8549-2010; McChesney, Jessica/K-8911-2013 OI Rotenberg, Eli/0000-0002-3979-8844; Seyller, Thomas/0000-0002-4953-2142; McChesney, Jessica/0000-0003-0470-2088 NR 42 TC 15 Z9 15 U1 1 U2 29 PU SPRINGER HEIDELBERG PI HEIDELBERG PA TIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANY SN 1951-6355 J9 EUR PHYS J-SPEC TOP JI Eur. Phys. J.-Spec. Top. PD SEP PY 2007 VL 148 BP 5 EP 13 DI 10.1140/epjst/e2007-00220-x PG 9 WC Physics, Multidisciplinary SC Physics GA 214SI UT WOS:000249758000002 ER PT J AU Huang, CF Kaur, J Maguitman, A Rocha, LM AF Huang, Chien-Feng Kaur, Jasleen Maguitman, Ana Rocha, Luis M. TI Agent-based model of genotype editing SO EVOLUTIONARY COMPUTATION LA English DT Article DE RNA Editing; Genotype Editing; Genetic Algorithms; agent-based modeling; coevolution; indirect genotype/phenotype mapping; dynamic environments; biologically-inspired computing ID GENETIC ALGORITHMS; RNA; DNA AB Evolutionary algorithms rarely deal with ontogenetic, non-inherited alteration of genetic information because they are based on a direct genotype-phenotype mapping. In contrast, several processes have been discovered in nature which alter genetic information encoded in DNA before it is translated into amino-acid chains. Ontogenetically altered genetic information is not inherited but extensively used in regulation and development of phenotypes, giving organisms the ability to, in a sense, re-program their genotypes according to environmental cues. An example of post-transcriptional alteration of gene-encoding sequences is the process of RNA. Editing. Here we introduce a novel Agent-based model of genotype editing and a computational study of its evolutionary performance in static and dynamic environments. This model builds on our previous Genetic Algorithm with Editing, but presents a fundamentally novel architecture in which coding and non-coding genetic components are allowed to co-evolve. Our goals are: (1) to study the role of RNA Editing regulation in the evolutionary process, (2) to understand how genotype editing leads to a different, and novel evolutionary search algorithm, and (3) the conditions under which genotype editing improves the optimization performance of traditional evolutionary algorithms. We show that genotype editing allows evolving agents to perform better in several classes of fitness functions, both in static and dynamic environments. We also present evidence that the indirect genotype/phenotype mapping resulting from genotype editing leads to a better exploration/ exploitation compromise of the search process. Therefore, we show that our biologically-inspired model of genotype editing can be used to both facilitate understanding of the evolutionary role of RNA regulation based on genotype editing in biology, and advance the current state of research in Evolutionary Computation. C1 Indiana Univ, Bloomington, IL 47406 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Nacl Sur, RA-8000 Bahia Blanca, Buenos Aires, Argentina. RP Rocha, LM (reprint author), Indiana Univ, Bloomington, IL 47406 USA. EM rocha@indiana.edu OI Kaur, Jasleen/0000-0002-1243-1452; Rocha, Luis/0000-0001-9402-887X NR 41 TC 3 Z9 3 U1 0 U2 0 PU M I T PRESS PI CAMBRIDGE PA 238 MAIN STREET, STE 500, CAMBRIDGE, MA 02142-1046 USA SN 1063-6560 J9 EVOL COMPUT JI Evol. Comput. PD FAL PY 2007 VL 15 IS 3 BP 253 EP 289 DI 10.1162/evco.2007.15.3.253 PG 37 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA 205XV UT WOS:000249149400002 PM 17705779 ER PT J AU Moissl, C Osman, S La Duc, MT Dekas, A Brodie, E DeSantis, T Venkateswaran, K AF Moissl, Christine Osman, Shariff La Duc, Myron T. Dekas, Anne Brodie, Eoin DeSantis, Tadd Venkateswaran, Kasthuri TI Molecular bacterial community analysis of clean rooms where spacecraft are assembled SO FEMS MICROBIOLOGY ECOLOGY LA English DT Article DE spacecraft assembly facility; bacterial community analysis; 16S rRNA; clean room; planetary protection; astrobiology ID MICROBIAL-CONTAMINATION; OLIGOTROPHIC MICROORGANISMS; DIVERSITY; ENVIRONMENTS; SURVIVAL; IRRADIATION; STATION; UNIFRAC; SPORES; MARS AB Molecular bacterial community composition was characterized from three geographically distinct spacecraft-associated clean rooms to determine whether such populations are influenced by the surrounding environment or the maintenance of the clean rooms. Samples were collected from facilities at the Jet Propulsion Laboratory (JPL), Kennedy Space Flight Center (KSC), and Johnson Space Center (JSC). Nine clone libraries representing different surfaces within the spacecraft facilities and three libraries from the surrounding air were created. Despite the highly desiccated, nutrient-bare conditions within these clean rooms, a broad diversity of bacteria was detected, covering all the main bacterial phyla. Furthermore, the bacterial communities were significantly different from each other, revealing only a small subset of microorganisms common to all locations (e.g. Sphingomonas, Staphylococcus). Samples from JSC assembly room surfaces showed the greatest diversity of bacteria, particularly within the Alpha- and Gammaproteobacteria and Actinobacteria. The bacterial community structure of KSC assembly surfaces revealed a high presence of proteobacterial groups, whereas the surface samples collected from the JPL assembly facility showed a predominance of Firmicutes. Our study presents the first extended molecular survey and comparison of NASA spacecraft assembly facilities, and provides new insights into the bacterial diversity of clean room environments . C1 CALTECH, Jet Propuls Lab, Biotechnol & Planetary Protect Grp, Pasadena, CA 91109 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Environm Biotechnol, Berkeley, CA 94720 USA. RP Venkateswaran, K (reprint author), CALTECH, Jet Propuls Lab, Biotechnol & Planetary Protect Grp, MS 89-2,4800 Oak Grove Dr, Pasadena, CA 91109 USA. EM kjvenkat@jpl.nasa.gov RI Moissl-Eichinger, Christine/A-6682-2015; Brodie, Eoin/A-7853-2008 OI Moissl-Eichinger, Christine/0000-0001-6755-6263; Brodie, Eoin/0000-0002-8453-8435 NR 48 TC 59 Z9 59 U1 1 U2 19 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0168-6496 J9 FEMS MICROBIOL ECOL JI FEMS Microbiol. Ecol. PD SEP PY 2007 VL 61 IS 3 BP 509 EP 521 DI 10.1111/j.1574-6941.2007.00360.x PG 13 WC Microbiology SC Microbiology GA 203GA UT WOS:000248961900011 PM 17655710 ER PT J AU Panofsky, WKH AF Panofsky, Wolfgang K. H. TI Nuclear insecurity - Correcting Washington's dangerous posture SO FOREIGN AFFAIRS LA English DT Article AB The Bush administration has adopted a misguided and dangerous nuclear posture. Instead of recycling antiquated doctrines and building a new generation of warheads, the United States should drastically reduce its nuclear arsenal, strengthen the international nonproliferation regime, and move toward the eventual elimination of nuclear weapons. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Panofsky, WKH (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU COUNC FOREIGN RELAT INC PI NEW YORK PA 58 E 68TH ST, NEW YORK, NY 10021 USA SN 0015-7120 J9 FOREIGN AFF JI Foreign Aff. PD SEP-OCT PY 2007 VL 86 IS 5 BP 109 EP + PG 11 WC International Relations SC International Relations GA 202CT UT WOS:000248880300007 ER PT J AU Poulston, S Granite, EJ Pennline, HW Myers, CR Stanko, DP Hamilton, H Rowsell, L Smith, AWJ Ilkenhans, T Chu, W AF Poulston, Stephen Granite, Evan J. Pennline, Henry W. Myers, Christina R. Stanko, Dennis P. Hamilton, Hugh Rowsell, Liz Smith, Andrew W. J. Ilkenhans, Thomas Chu, Wilson TI Metal sorbents for high temperature mercury capture from fuel gas SO FUEL LA English DT Article; Proceedings Paper CT 6th European Meeting on Coal Research and Its Applications CY SEP, 2006 CL Univ Kent, Canterbury, ENGLAND HO Univ Kent DE mercury; coal; gasification ID COAL-GASIFICATION; REMOVAL AB have determined the Hg removal capacities of Pt and Pd supported on alumina at a range of different metal loadings from 2 to 9 wt%,, using Hg vapour in a simulated fuel gas feed. In the temperature range studied (204-388 degrees C) Pd proved far superior to Pt for Hg removal. The Hg removal capacity for both Pt and Pd increased with metal loading, though decreased with sorbent temperature. A shift in the 20 position of the Pd XRD diffraction peak from 82.1 to 79.5 after Hg adsorption at 204 degrees C was consistent with the formation of a solid solution of fig in Pd. (c) 2007 Elsevier Ltd. All rights reserved. C1 Johnson Matthey Technol Ctr, Reading RG4 9NH, Berks, England. US DOE, Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. Stationary Source Emiss Control, Malvern, PA 19382 USA. RP Poulston, S (reprint author), Johnson Matthey Technol Ctr, Reading RG4 9NH, Berks, England. EM Poulss@matthey.com NR 11 TC 54 Z9 63 U1 0 U2 16 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0016-2361 J9 FUEL JI Fuel PD SEP PY 2007 VL 86 IS 14 BP 2201 EP 2203 DI 10.1016/j.fuel.2007.05.015 PG 3 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 211TQ UT WOS:000249546600022 ER PT J AU Gupta, N Tanner, S Jaitly, N Adkins, JN Lipton, M Edwards, R Romine, M Osterman, A Bafna, V Smith, RD Pevzner, PA AF Gupta, Nitin Tanner, Stephen Jaitly, Navdeep Adkins, Joshua N. Lipton, Mary Edwards, Robert Romine, Margaret Osterman, Andrei Bafna, Vineet Smith, Richard D. Pevzner, Pavel A. TI Whole proteome analysis of post-translational modifications: Applications of mass-spectrometry for proteogenomic annotation SO GENOME RESEARCH LA English DT Article ID SHEWANELLA-ONEIDENSIS MR-1; ESCHERICHIA-COLI K-12; SALMONELLA-TYPHIMURIUM; INITIATION FACTOR-IF3; HYPOTHETICAL PROTEINS; COMPARATIVE GENOMICS; RIBOSOMAL-PROTEINS; SENSORY TRANSDUCER; SIGNAL PEPTIDES; IDENTIFICATION AB While bacterial genome annotations have significantly improved in recent years, techniques for bacterial proteome annotation (including post-translational chemical modifications, signal peptides, proteolytic events, etc.) are still in their infancy. At the same time, the number of sequenced bacterial genomes is rising sharply, far outpacing our ability to validate the predicted genes, let alone annotate bacterial proteomes. In this study, we use tandem mass spectrometry (MS/MS) to annotate the proteome of Shewanella oneidensis MR-1, an important microbe for bioremediation. In particular, we provide the first comprehensive map of post-translational modifications in a bacterial genome, including a large number of chemical modifications, signal peptide cleavages, and cleavages of N-terminal methionine residues. We also detect multiple genes that were missed or assigned incorrect start positions by gene prediction programs, and suggest corrections to improve the gene annotation. This study demonstrates that complementing every genome sequencing project by an MS/MS project would significantly improve both genome and proteome annotations for a reasonable cost. C1 Univ Calif San Diego, Bioinformat Program, La Jolla, CA 92039 USA. Pacific NW Natl Lab, Div Biol Sci, Richland, WA 99352 USA. Burnham Inst Med Res, La Jolla, CA 92037 USA. Fellowship Interpretat Genomes, Burr Ridge, IL 60527 USA. San Diego State Univ, San Diego, CA 92182 USA. Univ Calif San Diego, Dept Comp Sci & Engn, La Jolla, CA 92093 USA. RP Gupta, N (reprint author), Univ Calif San Diego, Bioinformat Program, La Jolla, CA 92039 USA. EM ngupta@ucsd.edu RI Gupta, Nitin/G-2420-2010; Smith, Richard/J-3664-2012; Adkins, Joshua/B-9881-2013; OI Gupta, Nitin/0000-0002-8408-3848; Smith, Richard/0000-0002-2381-2349; Adkins, Joshua/0000-0003-0399-0700; Romine, Margaret/0000-0002-0968-7641 FU NCRR NIH HHS [1-R01-RR16522, C06 RR017588, P41 RR008605, P41 RR08605, R01 RR016522] NR 88 TC 132 Z9 137 U1 2 U2 17 PU COLD SPRING HARBOR LAB PRESS, PUBLICATIONS DEPT PI COLD SPRING HARBOR PA 1 BUNGTOWN RD, COLD SPRING HARBOR, NY 11724 USA SN 1088-9051 J9 GENOME RES JI Genome Res. PD SEP PY 2007 VL 17 IS 9 BP 1362 EP 1377 DI 10.1101/gr.6427907 PG 16 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity GA 207FL UT WOS:000249236900013 PM 17690205 ER PT J AU Krot, AN Yurimoto, H Hutcheon, ID Libourel, G Chaussidon, M Tissandier, L Petaev, MI MacPherson, GJ Paque-Heather, J Wark, D AF Krot, Alexander N. Yurimoto, Hisayoshi Hutcheon, Ian D. Libourel, Guy Chaussidon, Marc Tissandier, Laurent Petaev, Michael I. MacPherson, Glenn J. Paque-Heather, Julie Wark, David TI Type CCa, Al-rich inclusions from Allende: Evidence for multistage formation SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID NINGQIANG CARBONACEOUS CHONDRITE; OXYGEN ISOTOPIC COMPOSITIONS; REDUCED-CV CHONDRITES; EARLY SOLAR-SYSTEM; REFRACTORY INCLUSIONS; FERROMAGNESIAN CHONDRULES; CRYSTALLIZATION SEQUENCES; GENETIC LINKS; B INCLUSIONS; CONDENSATION AB The coarse-grained, igneous, anorthite-rich (Type C) CAIs from Allende studied (100, 160, 6-1-72, 3529-40, CG5, ABC, TS26, and 93) have diverse textures and mineralogies, suggesting complex nebular and asteroidal formation histories. CAIs 100, 160, 6-1-72, and 3529-40 consist of Al,Ti-diopside (fassaite; 13-23 wt% Al2O3, 2-14 wt% TiO2), Na-bearing akermanitic melilite (0.1-0.4 wt% Na2O; Ak(30-75)), spinel, and fine-grained (similar to 5-10 pm) anorthite groundmass. Most of the fassaite and melilite grains have "lacy" textures characterized by the presence of abundant rounded and prismatic inclusions of anorthite similar to 5-10 mu m in size. Lacy melilite is pseudomorphed to varying degrees by grossular, monticellite, and pure forsterite or wollastonite. spinel, perovskite, and platinum-group element nuggets; the Type B-like material is overgrown by lacy melilite and fassaite. Some melilite and fassaite grains in CAls 100 and 160 are texturally similar to those in the Type B portion of 6-1-72. CAls ABC and TS26 contain relict chondrule fragments composed of forsteritic olivine and low-Ca pyroxene; CAI 93 is overgrown by a coarse-grained igneous rim of pigeonite, augite, and anorthitic plagioclase. These three CAls contain very sodium-rich akermanitic melilite (0.4-0.6 wt% Na2O; Ak(63-7)4) and Cr-bearing AI,Ti-diopside (up to 1.6 wt% Cr2O3, 1-23 wt% Al2O, 0.5-7 wt% TiO2). Melilite and anorthite in the Allende Type C CAI peripheries are replaced by nepheline and socialite, which are crosscut by andradite-bearing veins; spinel is enriched in FeO. The CAI fragment CG5 is texturally and mineralogically distinct from other Allende Type Cs. It is anorthite-poor and very rich in spinel poikilitically enclosed by Na-free gehlenitic melilite (Ak(20-30)), fassaite, and anorthite; neither melilite nor pyroxene have lacy textures; secondary minerals are absent. The Al-rich chondrules 3655b-2 and 3510-7 contain aluminum-rich and ferromagnesian portions. The Al-rich portions consist of anorthitic plagioclase, Al-rich low-Ca pyroxene, and Cr-bearing spinel; the ferromagnesium portions consist of fosteritic olivine, low-Ca pyroxene, and opaque nodules. C1 Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Hawai Inst Geophys & Planetol, Honolulu, HI 96822 USA. Tokyo Inst Technol, Dept Earth & Planetary Sci, Tokyo 1528551, Japan. Lawrence Livermore Natl Lab, Livermore, CA 94451 USA. CNRS, UPR 2300, Ctr Rech Petrog & Geochim, F-54501 Vandoeuvre Les Nancy, France. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. Smithsonian Inst, Dept Mineral Sci, Washington, DC 20560 USA. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. Univ Melbourne, Parkville, Vic 3010, Australia. RP Krot, AN (reprint author), Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Hawai Inst Geophys & Planetol, Honolulu, HI 96822 USA. EM sasha@higp.hawaii.edu RI Chaussidon, Marc/E-7067-2017 NR 60 TC 25 Z9 25 U1 4 U2 18 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD SEP 1 PY 2007 VL 71 IS 17 BP 4342 EP 4364 DI 10.1016/j.gca.2007.03.040 PG 23 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 209CD UT WOS:000249365000015 ER PT J AU Phillips, BR Bunge, HP AF Phillips, Benjamin R. Bunge, Hans-Peter TI Supercontinent cycles disrupted by strong mantle plumes SO GEOLOGY LA English DT Article DE supercontinent cycles; mantle convection; plumes; numerical model ID DEPTH-DEPENDENT VISCOSITY; MESOPROTEROZOIC SUPERCONTINENT; CONVECTION MODELS; POLAR WANDER; DEEP MANTLE; CONTINENTS; FLOW; AGGREGATION; GENERATION; HYPOTHESIS AB A theoretical basis for the regularity of supercontinent cycles is lacking. Here we show that periodic supercontinent cycles are unlikely if thermal instabilities originating at the core-mantle boundary are of sufficient strength. We couple multiple mobile continents with vigorous mantle convection in a spherical geometry. Regular supercontinent cycles lasting 400 +/- 50 m.y. occur in idealized models with three continents and a mantle heated purely from within by radioactive decay. In a model incorporating six continents and strong mantle plumes, this regularity is broken and supercontinents form only sporadically. Our results suggest that periodic supercontinent cycles are unlikely to occur in realistic Earth models. C1 Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. Univ Munich, Dept Earth & Environm Sci, D-80333 Munich, Germany. RP Phillips, BR (reprint author), Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. NR 37 TC 32 Z9 36 U1 1 U2 14 PU GEOLOGICAL SOC AMER, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD SEP PY 2007 VL 35 IS 9 BP 847 EP 850 DI 10.1130/G23686A.1 PG 4 WC Geology SC Geology GA 209BD UT WOS:000249362200020 ER PT J AU Daley, TM Solbau, RD Ajo-Franklin, JB Benson, SM AF Daley, Thomas M. Solbau, Ray D. Ajo-Franklin, Jonathan B. Benson, Sally M. TI Continuous active-source seismic monitoring of CO2 injection in a brine aquifer SO GEOPHYSICS LA English DT Letter ID TRAVEL-TIME; CROSS-WELL; RESERVOIR AB Continuous crosswell seismic monitoring of a small-scale CO2 injection was accomplished with the development of a novel tubing-deployed piezoelectric borehole source. This piezotube source was deployed on the CO2 injection tubing, near the top of the saline aquifer reservoir at 1657-m depth, and allowed acquisition of crosswell recordings at 15-minute intervals during the multiday injection. The change in traveltime recorded at various depths in a nearby observation well allowed hour-by-hour monitoring of the growing CO2 plume via the induced seismic velocity change. Traveltime changes of 0.2 to 1.0 ms (up to 8%) were observed, with no change seen at control sensors placed above the reservoir. The traveltime measurements indicate that the CO2 plume reached the top of the reservoir sand before reaching the observation well, where regular fluid sampling was occuring during the injection, thus providing information about the in situ buoyancy of CO2. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. MIT, Earth Resources Lab, Cambridge, MA 02139 USA. RP Daley, TM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. EM tmdaley@lbl.gov; rdsolbau@lbl.gov; jonathan.ajofranklin@gmail.com; smbenson@stanford.edu RI Daley, Thomas/G-3274-2015; Ajo-Franklin, Jonathan/G-7169-2015; OI Daley, Thomas/0000-0001-9445-0843; Ajo-Franklin, Jonathan/0000-0002-6666-4702 NR 15 TC 32 Z9 32 U1 1 U2 11 PU SOC EXPLORATION GEOPHYSICISTS PI TULSA PA 8801 S YALE ST, TULSA, OK 74137 USA SN 0016-8033 J9 GEOPHYSICS JI Geophysics PD SEP-OCT PY 2007 VL 72 IS 5 BP A57 EP A61 DI 10.1190/1.2754716 PG 5 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 213RA UT WOS:000249683600002 ER PT J AU Haney, MM AF Haney, Matthew M. TI Generalization of von Neumann analysis for a model of two discrete half-spaces: The acoustic case SO GEOPHYSICS LA English DT Article ID FINITE-DIFFERENCE SCHEMES; SEISMIC-WAVE PROPAGATION; HETEROGENEOUS MEDIA; STABILITY; SEISMOGRAMS; EQUATIONS AB Evaluating the performance of finite-difference algorithms typically uses a technique known as von Neumann analysis. For a given algorithm, application of the technique yields both a dispersion relation valid for the discrete timespace grid and a mathematical condition for stability. In practice, a major shortcoming of conventional von Neumann analysis is that it can be applied only to an idealized numerical model - that of an infinite, homogeneous whole space. Experience has shown that numerical instabilities often arise in finite-difference simulations of wave propagation at interfaces with strong material contrasts. These interface instabilities occur even though the conventional von Neumann stability criterion may be satisfied at each point of the numerical model. To address this issue, I generalize von Neumann analysis for a model of two half-spaces. I perform the analysis for the case of acoustic wave propagation using a standard staggered-grid finite-difference numerical scheme. By deriving expressions for the discrete reflection and transmission coefficients, I study under what conditions the discrete reflection and transmission coefficients become unbounded. I find that instabilities encountered in numerical modeling near interfaces with strong material contrasts are linked to these cases and develop a modified stability criterion that takes into account the resulting instabilities. I test and verify the stability criterion by executing a finite-difference algorithm under conditions predicted to be stable and unstable. C1 Sandia Natl Labs, Dept Geophys, Albuquerque, NM 87185 USA. RP Haney, MM (reprint author), USGS Alaska Volcano Observatory, Anchorage, AK USA. EM mhaney@usgs.gov NR 33 TC 1 Z9 1 U1 0 U2 0 PU SOC EXPLORATION GEOPHYSICISTS PI TULSA PA 8801 S YALE ST, TULSA, OK 74137 USA SN 0016-8033 J9 GEOPHYSICS JI Geophysics PD SEP-OCT PY 2007 VL 72 IS 5 SU S BP SM35 EP SM46 DI 10.1190/1.2750639 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 217MV UT WOS:000249952900004 ER PT J AU Turetsky, MR Wieder, RK Vitt, DH Evans, RJ Scott, KD AF Turetsky, M. R. Wieder, R. K. Vitt, D. H. Evans, R. J. Scott, K. D. TI The disappearance of relict permafrost in boreal north America: Effects on peatland carbon storage and fluxes SO GLOBAL CHANGE BIOLOGY LA English DT Article DE boreal; carbon; CH4; climate change; CO2; degradation; litter quality; peat; peatlands permafrost ID CONTINENTAL WESTERN CANADA; CLIMATE-CHANGE; ACCUMULATION; DYNAMICS; ALASKA; DISEQUILIBRIUM; ECOSYSTEMS; PYROLYSIS; PATTERNS; ALBERTA AB Boreal peatlands in Canada have harbored relict permafrost since the Little Ice Age due to the strong insulating properties of peat. Ongoing climate change has triggered widespread degradation of localized permafrost in peatlands across continental Canada. Here, we explore the influence of differing permafrost regimes (bogs with no surface permafrost, localized permafrost features with surface permafrost, and internal lawns representing areas of permafrost degradation) on rates of peat accumulation at the southernmost limit of permafrost in continental Canada. Net organic matter accumulation generally was greater in unfrozen bogs and internal lawns than in the permafrost landforms, suggesting that surface permafrost inhibits peat accumulation and that degradation of surface permafrost stimulates net carbon storage in peatlands. To determine whether differences in substrate quality across permafrost regimes control trace gas emissions to the atmosphere, we used a reciprocal transplant study to experimentally evaluate environmental versus substrate controls on carbon emissions from bog, internal lawn, and permafrost peat. Emissions of CO2 were highest from peat incubated in the localized permafrost feature, suggesting that slow organic matter accumulation rates are due, at least in part, to rapid decomposition in surface permafrost peat. Emissions of CH4 were greatest from peat incubated in the internal lawn, regardless of peat type. Localized permafrost features in peatlands represent relict surface permafrost in disequilibrium with the current climate of boreal North America, and therefore are extremely sensitive to ongoing and future climate change. Our results suggest that the loss of surface permafrost in peatlands increases net carbon storage as peat, though in terms of radiative forcing, increased CH4 emissions to the atmosphere will partially or even completely offset this enhanced peatland carbon sink for at least 70 years following permafrost degradation. C1 Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA. Michigan State Univ, Dept Fisheries, E Lansing, MI 48824 USA. Michigan State Univ, Dept Wildlife, E Lansing, MI 48824 USA. So Illinois Univ, Dept Plant Biol, Carbondale, IL 62901 USA. Natl Renewable Energy Lab, Golden, CO USA. RP Turetsky, MR (reprint author), Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA. EM mrt@msu.edu RI Turetsky, Merritt/B-1255-2013 NR 30 TC 102 Z9 104 U1 6 U2 58 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 1354-1013 J9 GLOBAL CHANGE BIOL JI Glob. Change Biol. PD SEP PY 2007 VL 13 IS 9 BP 1922 EP 1934 DI 10.1111/j.1365-2486.2007.01381.x PG 13 WC Biodiversity Conservation; Ecology; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 207AA UT WOS:000249222800008 ER PT J AU Fountos, BN Rabovsky, JL AF Fountos, Barretr N. Rabovsky, Joel L. TI The department of energy's Russian health studies program SO HEALTH PHYSICS LA English DT Editorial Material C1 US Dept Energy Program Manager, Russian Hlth Studies Program, Off Int Hlth Studies, Germantown, MD 20874 USA. US DOE, Off Worker Safety & Hlth Policy, Germantown, MD 20874 USA. RP Fountos, BN (reprint author), US Dept Energy Program Manager, Russian Hlth Studies Program, Off Int Hlth Studies, HS 14-270 Corp Ctr Bldg,19901 Germantown Rd, Germantown, MD 20874 USA. EM Barrett.Fbuntos@hq.doe.gov NR 1 TC 12 Z9 16 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD SEP PY 2007 VL 93 IS 3 BP 187 EP 189 DI 10.1097/01.HP.0000265218.12646.63 PG 3 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 200TG UT WOS:000248785100001 PM 17693769 ER PT J AU Vasilenko, EK Khokhryakov, VF Miller, SC Fix, JJ Eckertnan, K Choe, DO Gorelov, M Khokhryakov, VV Knyasev, V Krahenbuhl, MP Scherpelz, RI Smetanin, M Suslova, K Vostrotint, V AF Vasilenko, E. K. Khokhryakov, V. F. Miller, S. C. Fix, J. J. Eckertnan, K. Choe, D. O. Gorelov, M. Khokhryakov, V. V. Knyasev, V. Krahenbuhl, M. P. Scherpelz, R. I. Smetanin, M. Suslova, K. Vostrotint, V. TI Mayak worker dosimetry study: An overview SO HEALTH PHYSICS LA English DT Article ID EXTRAPULMONARY ORGAN DISTRIBUTION; PRODUCTION-ASSOCIATION; PLUTONIUM WORKERS; TECHA RIVER; CHRONIC INHALATION; HEALTH; MODEL; EXCRETION; RECONSTRUCTION; CONTAMINATION AB The Mayak Production Association (MPA) was the first plutonium production plant in the former Soviet Union. Workers at the MPA were exposed to relatively large internal radiation intakes and external radiation exposures, particularly in the early years of plant operations. This paper describes the updated dosimetry database, "Doses-2005." Doses-2005 represents a significant improvement in the determination of absorbed organ dose from external radiation and plutonium intake for the original cohort of 18,831 Mayak workers. The methods of dose reconstruction of absorbed organ doses from external radiation uses: 1) archive records of measured dose and worker exposure history, 2) measured energy and directional response characteristics of historical Mayak film dosimeters, and 3) calculated dose conversion factors for Mayak Study-defined exposure scenarios using Monte Carlo techniques. The methods of dose reconstruction for plutonium intake uses two revised models developed from empirical data derived from bioassay and autopsy cases and/or updates from prevailing or emerging International Commission on Radiological Protection models. Other sources of potential significant exposure to workers such as medical diagnostic x-rays, ambient onsite external radiation, neutron radiation, intake of airborne effluent, and intake of nuclides other than plutonium were evaluated to determine their impact on the dose estimates. C1 So Urals Biophys Inst, Chelyabinsk 456780, Russia. Univ Utah, Div Radiobiol, Salt Lake City, UT 84108 USA. Mayak Prod Assoc, Ozyorsk, Russia. Dade Moeller & Associates, Richland, WA USA. Univ Utah, Div Nucl Engn, Salt Lake City, UT USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Miller, SC (reprint author), So Urals Biophys Inst, Ozyorskoye Shosse 19, Chelyabinsk 456780, Russia. EM khokh@lab3.fib.ozersk.ru; scott.miller@hsc.utah.edu NR 36 TC 53 Z9 74 U1 0 U2 5 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD SEP PY 2007 VL 93 IS 3 BP 190 EP 206 DI 10.1097/01.HP.0000266071.43137.0e PG 17 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 200TG UT WOS:000248785100002 PM 17693770 ER PT J AU Vasilenko, EK Knyazev, V Gorelov, M Smetanin, M Scherpelz, RI Fix, JJ AF Vasilenko, E. K. Knyazev, V. Gorelov, M. Smetanin, M. Scherpelz, R. I. Fix, J. J. TI Mayak film dosimeter response studies, part I: Measurements SO HEALTH PHYSICS LA English DT Article DE dose assessment; dosimetry, personnel; calibration; correction factors ID NUCLEAR WORKERS AB The Mayak Worker Dosimetry study is a joint Russian/U.S. project to evaluate doses received by workers at the Mayak Production Association facilities from 1948-1972. A key investigation in this project is the characterization of responses of the three types of film dosimeters used to monitor workers during this time period. Experimental irradiations of the dosimeters were performed in the radiation calibration laboratories at the National Research Center for Environment and Health (GSF) in Munich, Germany. The irradiations used photon sources from x-ray beams with ten different energy distributions and with Co-60 and (CS)-C-137 isotopic gamma sources. Irradiations were performed with the dosimeters on phantoms and free-in-air. The dosimeters and phantoms were also positioned at varying angles to the radiation beam. The result of the experiments was a thorough characterization of the dosimeter response as a function of photon energy and as a function of angle for energy and angular ranges that cover the conditions encountered in the Mayak workplaces. The characterization data were then available for use in developing correction factors, which could be applied to worker dosimeter readings to provide a more accurate assessment of worker dose and estimates of doses to organs. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Mayak Prod Assoc, Ozyorsk, Russia. Dade Moeller & Associates, Richland, WA USA. RP Scherpelz, RI (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM scherpelz@pnl.gov NR 12 TC 7 Z9 11 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD SEP PY 2007 VL 93 IS 3 BP 220 EP 230 DI 10.1097/01.HP.0000267861.63767.a7 PG 11 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 200TG UT WOS:000248785100004 PM 17693772 ER PT J AU Smetanin, M Vasilenko, EK Lyubarskaya, I Knyazev, V Gorelov, A Scherpelz, RI Fix, JJ AF Smetanin, M. Vasilenko, E. K. Lyubarskaya, I. Knyazev, V. Gorelov, A. Scherpelz, R. I. Fix, J. J. TI Mayak film dosimeter response studies, part II: Response models SO HEALTH PHYSICS LA English DT Article AB A study was performed of energy and angular responses of the film dosimeters that were used for worker monitoring at the Mayak Production Association (Mayak PA) in 1948-1992. The study used experimental data from tests with three types of individual film dosimeters, and the data were used to determine the dosimeters' energy and angular response characteristics in the range from 9 keV to Co-60 energies, with the dosimeters exposed both free-in-air and on-phantom at horizontal and vertical rotation. Mathematical models of the dosimeters were developed to calculate the response characteristics of the dosimeters. The models of the film dosimeters were validated by comparing calculations to measurements. The models were then used as the basis for individual dose reconstruction in realistic photon spectra and worker exposure geometries at the Mayak PA workplaces. Reconstructed individual doses have been included in the Mayak worker database "Doses-2005" that is used for epidemiological studies of the Mayak workers' radiation exposures and subsequent health effects. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Mayak Prod Assoc, Ozyorsk, Russia. Dade Moeller & Associates, Richland, WA USA. RP Scherpelz, RI (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM scherpelz@pni.gov NR 3 TC 8 Z9 13 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD SEP PY 2007 VL 93 IS 3 BP 231 EP 238 DI 10.1097/01.HP.0000268729.56660.b9 PG 8 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 200TG UT WOS:000248785100005 PM 17693773 ER PT J AU Smetanin, M Vasilenko, EK Scherpelz, RI AF Smetanin, M. Vasilenko, E. K. Scherpelz, R. I. TI Mayak film dosimeter response studies, part III: Application to worker dose assessment SO HEALTH PHYSICS LA English DT Article AB This paper describes the methods used to correct individual dosimeter readings for workers to obtain estimates of worker doses received at the Mayak Production Association (Mayak PA). Film dosimeters were used at Mayak PA for worker monitoring from 1948 until 1992. The method requires a determination of the relationship between the absorbed dose in film emulsion and the dose in air under calibration conditions, which is then extended to exposures in the actual radiation fields of the workplace. Corrections needed to account for actual workplace exposure conditions were determined by modeling with the Monte Carlo radiation transport computer code MCNP. Correction factors were developed to convert from dosimeter reading to a realistic worker dose. The method was applied as a basis for individual dose reconstruction using film dosimeters in realistic photon spectra and geometries at Mayak PA work areas. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Mayak Prod Assoc, Ozyorsk, Russia. RP Scherpelz, RI (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM scherpelz@pnl.gov NR 5 TC 7 Z9 11 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD SEP PY 2007 VL 93 IS 3 BP 239 EP 244 DI 10.1097/01.HP.0000268727.68079.d7 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 200TG UT WOS:000248785100006 PM 17693774 ER PT J AU Diamond, DL Jacobs, JM Paeper, B Proll, SC Gritsenko, MA Carithers, RL Larson, AM Yeh, MM Camp, DG Smith, RD Katze, MG AF Diamond, Deborah L. Jacobs, Jon M. Paeper, Bryan Proll, Sean C. Gritsenko, Marina A. Carithers, Robert L., Jr. Larson, Aflne M. Yeh, Matthew M. Camp, David G., II Smith, Richard D. Katze, Michael G. TI Proteomic profiling of human liver biopsies: hepatitis C virus-induced fibrosis and mitochondrial dysfunction SO HEPATOLOGY LA English DT Article ID TANDEM MASS-SPECTROMETRY; LIQUID-CHROMATOGRAPHY; QUANTITATIVE PROTEOMICS; OXIDATIVE STRESS; INFECTION; MECHANISMS; EXPRESSION; CELLS; ELECTROPHORESIS; STEATOSIS AB Liver biopsies from hepatitis C virus (HCV)-infected patients offer the unique opportunity to study human liver biology and disease in vivo. However, the low protein yields associated with these small samples present a significant challenge for proteomic analysis. In this study we describe the application of an ultrasensitive proteomics platform for performing robust quantitative proteomic studies on microgram amounts of HCV-infected human liver tissue from 15 patients at different stages of fibrosis. A high-quality liver protein database containing 5,920 unique protein identifications supported high throughput quantitative studies using O-16/O-18 stable isotope labeling in combination with the accurate mass and time (AMT) tag approach. A total of 1,641 liver biopsy proteins were quantified, and analysis of variance (ANOVA) identified 210 proteins exhibiting statistically significant differences associated with fibrosis stage. Hierarchical clustering showed that biopsies representative of later fibrosis stages (for example, Batts-Ludwig stages 3-4) exhibited a distinct protein expression profile, indicating an apparent down-regulation of many proteins when compared with samples from earlier fibrosis stages (for example, Batts-Ludwig stages 0-2). Functional analysis of these signature proteins suggests that impairment of key mitochondrial processes including fatty acid oxidation and oxidative phosphorylation, and response to oxidative stress and reactive oxygen species occurs during advanced stage 3 to 4 fibrosis. Conclusion: The results reported here represent a significant advancement in clinical proteomics providing to our knowledge, the first demonstration of global proteomic alterations accompanying liver disease progression in patients chronically infected with HCV. Our findings contribute to a generally emerging theme associating oxidative stress and hepatic mitochondrial dysfunction with HCV pathogenesis. C1 Univ Washington, Dept Microbiol, Seattle, WA 98195 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Div Biol Sci, Richland, WA 99352 USA. Univ Washington, Dept Med, Hepatol Sect, Seattle, WA USA. Univ Washington, Sch Med, Dept Pathol, Seattle, WA 98195 USA. Univ Washington, Washington Natl Primate Res Ctr, Seattle, WA 98195 USA. RP Diamond, DL (reprint author), Univ Washington, Dept Microbiol, Box 358070, Seattle, WA 98195 USA. EM ddiamond@u.washington.edu RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 FU NCRR NIH HHS [RR18522]; NIDA NIH HHS [1P30DA01562501] NR 35 TC 74 Z9 77 U1 0 U2 4 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0270-9139 J9 HEPATOLOGY JI Hepatology PD SEP PY 2007 VL 46 IS 3 BP 649 EP 657 DI 10.1002/hep.21751 PG 9 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 206OA UT WOS:000249191600007 PM 17654742 ER PT J AU Timmons, EA Fisher, TG Hansen, EC Eisaman, E Daly, T Kashgarian, M AF Timmons, Emily A. Fisher, Timothy G. Hansen, Edward C. Eisaman, Elliott Daly, Trevor Kashgarian, Michaele TI Elucidating aeolian dune history from lacustrine sand records in the Lake Michigan Coastal Zone, USA SO HOLOCENE LA English DT Article DE sand dunes; acolian sand; Lake Michigan; palaeosols; OSL ages; inland lake sediments; Holocene ID SOUTHEASTERN SHORE; SILVER-LAKE; AIR-FLOW; HOLOCENE; SEDIMENT; SUPERIOR; LEVEL; TRANSPORT; BASIN AB Aeolian sand in two small lakes within a Lake Michigan coastal-dune complex southwest of Holland, Michigan, provides a more detailed higher-resolution history of dune activity, during the later half of the Holocene, than do combined palaeosol and OSL ages from the dunes themselves. The sand signal from four cores within these takes consists of visible sand laminae and invisible sand peaks within mud and sapropel units. Early in the history of dune growth the sand may have come from backdunes immediately adjacent to the lakes, but in the upper portions of the core aeolian sand is interpreted as having been transported from 30-40 m high parabolic dunes similar to 200 m from the lakes. All but one episode of dune mobility suggested by radiocarbon-dated dune palaeosols or OSL-dated dune sand are represented by a peak in the radiocarbon-dated lacustrine sand signal. However, sand peaks occur in the lacustrine record that do not correspond to palaeosol or OSL ages, suggesting that the sand record from small lakes gives a more complete record of aeolian activity. Heterogeneity in sand deposition related to bathymetry suggests that the study of multiple cores from the same lake will yield the best results. No strong correlation between rising lake levels on the Lake Michigan relative lake level curve and aeolian activity was found, although such a correlation has been reported elsewhere. C1 Hope Coll, Dept Geog & Environm Sci, Holland, MI 49423 USA. Univ Toledo, Dept Environm Sci, Toledo, OH 43606 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. RP Hansen, EC (reprint author), Hope Coll, Dept Geog & Environm Sci, Holland, MI 49423 USA. EM hansen@hope.edu RI Fisher, Timothy/C-2609-2011; Kashgarian, Michaele/E-1665-2011 OI Kashgarian, Michaele/0000-0001-7824-8418 NR 32 TC 18 Z9 18 U1 1 U2 10 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 0959-6836 J9 HOLOCENE JI Holocene PD SEP PY 2007 VL 17 IS 6 BP 789 EP 801 DI 10.1177/0959683607080520 PG 13 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 226XZ UT WOS:000250623100008 ER PT J AU Kollet, SJ Zlotnik, VA AF Kollet, Stefan J. Zlotnik, Vitaly A. TI Evaluation of the streambed leakage concept in analytical models using data from three pumping tests SO HYDROGEOLOGY JOURNAL LA English DT Article DE groundwater/surface-water relations; hydraulic testing; hydraulic properties; groundwater hydraulics ID FLOW DEPLETION; UNCONFINED AQUIFERS; TEMPERATURE; DRAWDOWN; WELLS; RIVER AB Two-dimensional analytical models of pumping induced drawdown and stream depletion account for the streambed properties and stream geometry. Using data from three pumping tests performed under various hydrologic conditions, the following hypotheses were tested: (1) a partially penetrating stream at a certain distance from the pumping well can be represented by the streambed leakage term in the analytical models; (2) in the streambed leakage term, the streambed conductance coefficient lambda=(WK')/m' accounts for the average stream width W, the streambed thickness m', and hydraulic conductivity K'. The first hypothesis was tested by comparing results from tests under flow and no-flow stream conditions. The second hypothesis was tested by comparing results from two tests under low and high streamflow conditions. Similar estimates of the hydraulic conductivity and storativity for all tests indicate the validity of the streambed leakage term. The drawdown data of the test under low- and high-flow conditions (varying W) do not follow the predictions of the analytical models, which results in inconsistent lambda estimates. Thus, for different hydrologic conditions, lambda cannot be scaled solely by the stream width W. One possible explanation for this result is streambed dynamics caused by the changes in the stream stage. C1 Lawrence Livermore Natl Lab, Div Environm Sci, Livermore, CA 94550 USA. Univ Nebraska, Dept Geosci, Lincoln, NE 68588 USA. RP Kollet, SJ (reprint author), Lawrence Livermore Natl Lab, Div Environm Sci, 700 E Ave, Livermore, CA 94550 USA. EM kollet2@llnl.gov NR 50 TC 5 Z9 5 U1 1 U2 9 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1431-2174 J9 HYDROGEOL J JI Hydrogeol. J. PD SEP PY 2007 VL 15 IS 6 BP 1051 EP 1062 DI 10.1007/s10040-006-0156-7 PG 12 WC Geosciences, Multidisciplinary; Water Resources SC Geology; Water Resources GA 208EW UT WOS:000249303600002 ER PT J AU Liu, Y Jones, H Vaidya, S Perrone, M Tydlitat, B Nanda, AK AF Liu, Y. Jones, H. Vaidya, S. Perrone, M. Tydlitat, B. Nanda, A. K. TI Speech recognition systems on the cell broadband engine processor SO IBM JOURNAL OF RESEARCH AND DEVELOPMENT LA English DT Article AB In this paper we describe our design, implementation, and initial results of a prototype connected-phoneme-based speech recognition system on the Cell Broadband Engine (TM) (Cell/B.E.) processor. Automated speech recognition decodes speech samples into plaintext (other representations are possible) and must process samples at real-time rates. Fortunately, the computational tasks involved in this pipeline are highly data parallel and can receive significant hardware acceleration from vector-streaming architectures such as the Cell/B.E. Architecture. Identifying and exploiting these parallelism opportunities is challenging and critical to improving system performance. From our initial performance timings, we observed that a single Cell/B.E. processor can recognize speech from thousands of simultaneous voice channels in real time-a channel density that is orders of magnitude greater than the capacity of existing software speech recognizers based on CPUs (central processing units). This result emphasizes the potential for Cell/B.E. processor based speech recognition and will likely lead to the development of production speech systems using Cell/B.E. processor clusters. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. IBM Corp, Thomas J Watson Res Ctr, IBM Res Div, Yorktown Hts, NY 10598 USA. IBM Czech Republ, Voice Technol & Syst, Prague 14800 4, Czech Republic. RP Liu, Y (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave, Livermore, CA 94550 USA. EM liu24@llnl.gov; holgerjones@llnl.gov; vaidyal@llnl.gov; mpp@us.ibm.com; borivoj_tydlitat@cz.ibm.com; ashwini@us.ibm.com NR 10 TC 4 Z9 4 U1 0 U2 2 PU IBM CORP PI ARMONK PA 1 NEW ORCHARD ROAD, ARMONK, NY 10504 USA SN 0018-8646 J9 IBM J RES DEV JI IBM J. Res. Dev. PD SEP PY 2007 VL 51 IS 5 BP 583 EP 591 PG 9 WC Computer Science, Hardware & Architecture; Multidisciplinary Sciences SC Computer Science; Science & Technology - Other Topics GA 214NX UT WOS:000249746300008 ER PT J AU Black, CT Ruiz, R Breyta, G Cheng, JY Colburn, ME Guarini, KW Kim, HC Zhang, Y AF Black, C. T. Ruiz, R. Breyta, G. Cheng, J. Y. Colburn, M. E. Guarini, K. W. Kim, H.-C. Zhang, Y. TI Polymer self assembly in semiconductor microelectronics SO IBM JOURNAL OF RESEARCH AND DEVELOPMENT LA English DT Review ID COPOLYMER THIN-FILMS; SYMMETRIC DIBLOCK COPOLYMER; ORGANOMETALLIC BLOCK-COPOLYMERS; FIELD-EFFECT TRANSISTORS; ELECTRIC-FIELD; IMMISCIBLE POLYMERS; PATTERNED MEDIA; TEMPERATURE-DEPENDENCE; INTERACTION PARAMETER; NANOSCOPIC TEMPLATES AB We are inspired by the beauty, and simplicity of self-organizing materials and the promise they hold for enabling continued improvementsi in semiconductor technology. Self assembly is the spontaneous arrangement of individual elements into regular patterns; under suitable conditions, certain materials self organize nanometer-scale patterns of importance to high-performance microelectronics applications. Polymer self assembly is a nontraditional approach to patterning integrated circuit elements at dimensions and densities inaccessible to traditional lithography methods. We review here our efforts in IBM to develop and integrate self-assembly processes as high-resolution patterning alternatives and to demonstrate targeted applications in semiconductor device,fabrication. We also provide a framework for understanding key requirenients for the adoption of polymer self-assembly processes into semiconductor technology, as well as a discussion of the ultimate dimensional scalability of the technique. C1 Brookhaven Natl Lab, Ctr Funct Nanomat, Upton, NY 11973 USA. Hitachi Global Storage Technol, San Jose, CA 95135 USA. IBM Res Corp, Almaden Res Ctr, IBM Res Div, San Jose, CA 95120 USA. IBM Corp, Thomas J Watson Res Ctr, IBM Res Div, Yorktown Hts, NY 10598 USA. IBM Syst & Technol Grp, Poughkeepsie, NY 12601 USA. RP Black, CT (reprint author), Brookhaven Natl Lab, Ctr Funct Nanomat, Upton, NY 11973 USA. EM ctblack@bnl.gov; ricardo.ruiz@hitachigst.com; breyta@us.ibm.com; chengjo@us.ibm.com; mcolburn@us.ibm.com; kwg@us.ibm.com; hckim@us.ibm.com; zhangy@us.ibm.com OI Ruiz, Ricardo/0000-0002-1698-4281 NR 177 TC 302 Z9 303 U1 3 U2 112 PU IBM CORP PI ARMONK PA 1 NEW ORCHARD ROAD, ARMONK, NY 10504 USA SN 0018-8646 EI 2151-8556 J9 IBM J RES DEV JI IBM J. Res. Dev. PD SEP PY 2007 VL 51 IS 5 BP 605 EP 633 PG 29 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA 214NX UT WOS:000249746300010 ER PT J AU Hennessey, B Wesson, RB Norman, B AF Hennessey, Brian Wesson, Robert B. Norman, Bradley TI Security simulation for vulnerability assessment SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB This discusses simulation technologies developed to "stimulate" an operational command and control security system. Herein, we discuss simulation techniques used to create a virtual model of a facility in which to conduct vulnerability assessment exercises, performance benchmarking, Concept Of Operations (CONOPS) development and operator training. This discusses specific techniques used for creating a 3d virtual environment and simulating streaming IP surveillance cameras and motion detection sensors. In addition, we discuss advanced scenario creation techniques and the modelling of scenario entities, including vehicles, aircraft and personnel. This draws parallels with lessons learned in using Air Traffic Control simulators for operator training, incident recreation, procedure development, and pre-acquisition planning and testing. C1 Adacel Syst Inc, Orlando, FL 32822 USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Hennessey, B (reprint author), Adacel Syst Inc, 6200 Lee Vista Blvd, Orlando, FL 32822 USA. NR 3 TC 1 Z9 1 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD SEP PY 2007 VL 22 IS 9 BP 11 EP 16 DI 10.1109/MAES.2007.4350253 PN 1 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 223LC UT WOS:000250370700003 ER PT J AU Cook, K Earnshaw, R Stasko, J AF Cook, Kris Earnshaw, Rae Stasko, John TI Discovering the unexpected SO IEEE COMPUTER GRAPHICS AND APPLICATIONS LA English DT Editorial Material C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Bradford, Bradford BD7 1DP, W Yorkshire, England. Georgia Inst Technol, Atlanta, GA 30332 USA. RP Cook, K (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM kris.cook@pnl.gov; r.a.earnshaw@bradford.ac.uk; stasko@cc.gatech.edu NR 6 TC 15 Z9 15 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0272-1716 J9 IEEE COMPUT GRAPH JI IEEE Comput. Graph. Appl. PD SEP-OCT PY 2007 VL 27 IS 5 BP 15 EP 19 DI 10.1109/MCG.2007.126 PG 5 WC Computer Science, Software Engineering SC Computer Science GA 207IP UT WOS:000249245100004 PM 17913020 ER PT J AU Bank, SR Bae, H Goddard, LL Yuen, HB Wistey, MA Kudrawiec, R Harris, JS AF Bank, Seth R. Bae, Hopil Goddard, Lynford L. Yuen, Homan B. Wistey, Mark A. Kudrawiec, Robert Harris, James S., Jr. TI Recent progress on 1.55-mu m dilute-nitride lasers SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE 1.55 mu m; annealing; auger recombination; continuous wave (CW); dilute nitride; GaInNAs; GaInNAsSb; gallium arsenide; GaNAs; InGaAsN; intervalence band absorption; molecular beam epitaxy (MBE); optical communications; semiconductor laser ID MOLECULAR-BEAM EPITAXY; QUANTUM-WELL LASERS; 1.5-MU-M GAINNASSB LASERS; VERTICAL-CAVITY LASERS; WAVELENGTH SEMICONDUCTOR-LASERS; CHEMICAL-VAPOR-DEPOSITION; ASSISTED MBE GROWTH; 1.5 MU-M; TEMPERATURE-SENSITIVITY; MULTIQUANTUM WELLS AB We review the recent developments in GaAs-based 1.55-mu m lasers grown by molecular beam epitaxy (MBE). While materials growth is challenging, the growth window appears to be relatively broad and is described in detail. The key considerations for producing high-quality GaInNAsSb material emitting at 1.55-mu m regime are examined, including the nitrogen plasma conditions, ion removal from the nitrogen flux, surfactant-mediated growth, the roles of various V-III ratios, the growth temperature, the active region thermal budget, proper annealing, and composition. We find that emission may be tuned throughout the 1.55-mu m communications, band without penalty to the optical quality varying only one parameter-the total growth rate. This powerful result is validated by the demonstration of low-threshold edge-emitting lasers throughout the 1.55-mu m regime, including threshold current densities as low as 318 A/cm(2) at 1.54 mu m. Additional characterization by Z-parameter techniques, cavity length studies, and band offset measurements were performed to better understand the temperature stability of device performance. Lasing was extended as far as 1.63 mu m under nonoptimized growth conditions. The GaAs-based dilute-nitrides are emerging as a very promising alternative to InP-based materials at 1.55-mu m due to their high gain, greater range of achievable band offsets, as well as the availability of lattice-matched AlAs-GaAs materials and native oxide layers for vertical-cavity surface-emitting lasers (VCSELs). Indeed, this effort has enabled the first electrically injected C-band VCSEL on GaAs. C1 Univ Texas, Dept Elect & Comp Engn, Austin, TX 78712 USA. Stanford Univ, Solid State & Photon Lab, Stanford, CA 94305 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Translucent Inc, Palo Alto, CA 94303 USA. Univ Calif Santa Barbara, Elect & Comp Engn & Mat Dept, Santa Barbara, CA 93106 USA. Wroclaw Tech Univ, Inst Phys, PL-53345 Wroclaw, Poland. RP Bank, SR (reprint author), Univ Texas, Dept Elect & Comp Engn, Austin, TX 78712 USA. EM sbank@ece.texas.edu; hpbae@stanford.edu; goddard5@llnl.gov; homan@translucentinc.com; wistey@ece.ucsb.edu; robert.kudrawiec@pwr.wroc.pl; harris@snow.stanford.esu NR 90 TC 55 Z9 55 U1 3 U2 26 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD SEP-OCT PY 2007 VL 43 IS 9-10 BP 773 EP 785 DI 10.1109/JQE.2007.902301 PG 13 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 219PN UT WOS:000250097200005 ER PT J AU Pocha, MD Goddard, LL Bond, TC Nikolic, RJ Vernon, SP Kallman, JS Behymer, EM AF Pocha, Michael D. Goddard, Lynford L. Bond, Tiziana C. Nikolic, Rebecca J. Vernon, Stephen P. Kallman, Jeffrey S. Behymer, Elaine M. TI Electrical and optical gain lever effects in InGaAs double quantum-well diode lasers SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE amplitude modulation (AM); gain lever; photonic integrated circuits; semiconductor device measurement; semiconductor device simulation; semiconductor lasers ID MQW LASERS; EFFICIENCY; MODULATION; NOISE AB In multisection laser diodes, the amplitude or frequency modulation (AM or FM) efficiency can be improved using the gain lever effect. To study gain lever, InGaAs double quantum-well (DQW) edge-emitting lasers have been fabricated With integrated passive waveguides and dual sections providing a range of split ratios from 1:1 to 9:1. Both the electrical and the optical gain lever have been examined. An electrical gain lever with greater than 7-dB enhancement of AM efficiency was achieved within the range of appropriate dc biasing currents, but this gain dropped rapidly outside this range. We observed a 4-dB gain in the optical AM efficiency under nonideal biasing conditions. This value agreed with the measured gain for the electrical AM efficiency under similar conditions. We also examined the gain lever effect under large signal modulation for digital logic switching applications. To get a useful gain lever for optical gain quenched logic, a long control section is needed to preserve the gain lever strength and a long interaction length between the input optical signal and the lasing field of the diode must be provided. The gain lever parameter space has been fully characterized and validated against numerical simulations of a semi-3-D hybrid beam propagation method (BPM) model for the coupled electron-photon rate equation. We find that the optical gain lever can be treated using the electrical injection model, once the absorption in the sample is known. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Pocha, MD (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. EM pocha@llnl.gov NR 22 TC 9 Z9 10 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD SEP-OCT PY 2007 VL 43 IS 9-10 BP 860 EP 868 DI 10.1109/JQE.2007.902796 PG 9 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 219PN UT WOS:000250097200017 ER PT J AU Waldmueller, I Chow, WW Wanke, MC AF Waldmueller, Ines Chow, Weng W. Wanke, Michael C. TI Optically pumped electrically driven THz generation - An approach for an efficient room-temperature THz quantum cascade laser? SO IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS LA English DT Article DE gain without inversion; intersubband semiconductor laser; Manley-Rowe quantum limit; optical conversion; quantum cascade laser (QCL); terahertz (THz) generation ID MU-M AB We investigate an optically pumped electrically driven laser scheme as an approach for terahertz (THz) quantum cascade lasers.The scheme keeps the advantages of optical conversion, and increases the efficiency by recycling the pump photons. Using a microscopic theory based on the Maxwell-semiconductor Bloch equations, we demonstrate that the approach offers a path to room-temperature THz generation. Furthermore, we show how successful recovery of the pump intensity can yield optical conversion efficiencies exceeding the Manley-Rowe limit. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Cardiff Univ, Cardiff CF10 3XQ, Wales. Univ Arizona, Tucson, AZ 85721 USA. RP Waldmueller, I (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM iwaldmu@sandia.gov; wwchow@sandia.gov; mewanke@sandia.gov RI Montano, Ines/I-7497-2012 NR 19 TC 3 Z9 3 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1077-260X J9 IEEE J SEL TOP QUANT JI IEEE J. Sel. Top. Quantum Electron. PD SEP-OCT PY 2007 VL 13 IS 5 BP 1084 EP 1088 DI 10.1109/JSTQE.2007.903584 PN 1 PG 5 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 223ME UT WOS:000250373800007 ER PT J AU Chrostowski, L Faraji, B Hofmann, W Amann, MC Wieczorek, S AF Chrostowski, Lukas Faraji, Behnam Hofmann, Werner Amann, Markus-Christian Wieczorek, Sebastian TI 40 GHz bandwidth and 64 GHz resonance frequency in injection-locked 1.55 mu m VCSELs SO IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS LA English DT Article DE direct modulation; frequency response; optical injection locking; vertical-cavity surface-emitting lasers (VCSELs) ID EXTERNAL LIGHT INJECTION; SURFACE-EMITTING LASER; SEMICONDUCTOR-LASER; MODULATION BANDWIDTH; OPTICAL-INJECTION; SIGNAL ANALYSIS; LOCKING; ENHANCEMENT; NOISE AB Injection locking is shown to greatly enhance the resonance frequency of 1.55 mu m vertical-cavity surface-emitting lasers (VCSELs), from 10 to 60 GHz, under ultrahigh injection locking conditions. Using injection locking to increase the laser resonance frequency, together with a low parasitic VCSEL design, a 3 dB bandwidth of over 40 GHz was attained, a record broadband performance for directly modulated VCSELs. VCSELs with slightly detuned polarization modes are injection locked with controlled polarization angles. For the first time, a dual-resonance frequency response is observed, and is explained with a two polarization-mode injection-locked rate equation model. C1 Univ British Columbia, Dept Elect & Comp Engn, Vancouver, BC V6R 1T3, Canada. Tech Univ Munich, Walter Schottky Inst, D-85748 Garching, Germany. Univ Exeter, Math Res Inst, Exeter EX4 4QJ, Devon, England. Sandia Natl Labs, Albuquerque, NM 87185 USA. Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Texas A&M Univ, Inst Quantum Studies, College Stn, TX 77843 USA. RP Chrostowski, L (reprint author), Univ British Columbia, Dept Elect & Comp Engn, Vancouver, BC V6R 1T3, Canada. EM lukasc@ece.ubc.ca; behnamf@ece.ubc.ca; Werner.Hofmann@wsi.tum.de; mcamann@wsi.tu-muenchen.de; S.M.Wieczorek@exeter.ac.uk RI Chrostowski, Lukas/B-5014-2011 NR 32 TC 66 Z9 67 U1 2 U2 13 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1077-260X EI 1558-4542 J9 IEEE J SEL TOP QUANT JI IEEE J. Sel. Top. Quantum Electron. PD SEP-OCT PY 2007 VL 13 IS 5 BP 1200 EP 1208 DI 10.1109/JSTQE.2007.904417 PN 1 PG 9 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 223ME UT WOS:000250373800024 ER PT J AU Lehman, AC Choquette, KD AF Lehman, Ann C. Choquette, Kent D. TI One- and two-dimensional coherently coupled implant-defined vertical-cavity laser Arrays SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE coherent arrays; vertical-cavity surface-emitting; laser (VCSEL) ID SURFACE-EMITTING LASERS; PHASED-ARRAY; EMISSION AB Loss between elements of coherently coupled vertical-cavity surface-emitting laser (VCSEL) arrays typically causes out-of-phase operation with on-axis intensity nulls in the far-field. We show that in-phase evanescently coupled VCSEL arrays may be defined by proton implantation. An advantage for implanted in-phase coherently coupled VCSEL arrays is that this approach employs a simple and reliable fabrication process where the absence of loss between elements leads to in-phase coupling. We present data for 2, 3, and 4 element in-phase implant-defined coherently coupled VCSEL arrays. C1 Univ Illinois, Dept Elect & Comp Engn, Micro & Nanotechnol Lab, Urbana, IL 61801 USA. RP Lehman, AC (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. EM aclehman@gmail.com; choquett@uiuc.edu NR 16 TC 30 Z9 30 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD SEP-OCT PY 2007 VL 19 IS 17-20 BP 1421 EP 1423 DI 10.1109/LPT.2007.903503 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 221FK UT WOS:000250212600045 ER PT J AU Johnston, MMW Hansen, LE Wilson, DM Booksh, KS AF Johnston, Matthew Miacomet Winter Hansen, Lisa Eileen Wilson, Denise Michelle Booksh, Karl S. TI System-on-chip circuit architecture for eliminating interferents in surface plasmon resonance sensing systems SO IEEE SENSORS JOURNAL LA English DT Article DE analog integrated circuits; analog VLSI; chemical sensors; optical computation; optical sensors; surface plasmon resonance (SPR) ID REGRESSION AB This paper presents a system-on-chip circuit architecture that enables the extraction of concentration information directly from a surface plasmon resonance (SPR) probe, independent of ambient fluctuations in the reference medium, temperature, and background light. Compensation for these baseline (bulk) interferences is embedded into the baseline integration state of the photodetectors in the optical path, creating a "flat line" for the baseline [no analyte present/bulk refractive index (RI)] condition and the characteristic SPR dips for the measurement (analyte present) condition. A resolution of 2 x 10(-4) RI units is possible with this system, comparable to the 5 X 10(-4) RI unit resolution of conventional signal processing (software-based) approaches to processing the same data using a similar framework. This approach demonstrates experimentally the capability of the dip-based SPR probe in a portable footprint for detecting RI at resolution levels suitable for practical applications of these probes to field environments. C1 Intel Massachusetts Inc, Embedded & Commun Proc Div, Hudson, MA 01749 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Univ Washington, Dept Elect Engn, Seattle, WA 98195 USA. Arizona State Univ, Dept Biochem, Tempe, AZ 85287 USA. RP Johnston, MMW (reprint author), Intel Massachusetts Inc, Embedded & Commun Proc Div, Hudson, MA 01749 USA. EM denisew@u.washington.edu; kbooksh@asu.edu NR 14 TC 1 Z9 1 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1530-437X J9 IEEE SENS J JI IEEE Sens. J. PD SEP-OCT PY 2007 VL 7 IS 9-10 BP 1400 EP 1412 DI 10.1109/JSEN.2007.904234 PG 13 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Applied SC Engineering; Instruments & Instrumentation; Physics GA 214MQ UT WOS:000249742700032 ER PT J AU Small, W Wilson, TS Buckley, PR Benett, WJ Loge, JA Hartman, J Maitland, DJ AF Small, Ward, IV Wilson, Thomas S. Buckley, Patrick R. Benett, William J. Loge, Jeffrey A. Hartman, Jonathan Maitland, Duncan J. TI Prototype fabrication and preliminary in vitro testing of a shape memory endovascular thrombectomy device SO IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING LA English DT Article DE nitinol; shape memory alloy; shape memory polymer (SMP); stroke; thrombectomy ID MIDDLE CEREBRAL-ARTERY; ACUTE ISCHEMIC-STROKE; TISSUE-PLASMINOGEN ACTIVATOR; BASILAR ARTERY; BLOOD-FLOW; CAROTID-ARTERY; DIAMETER; THROMBOLYSIS; THROMBUS; VELOCITY AB An electromechanical microactuator comprised of shape memory polymer (SMP) and shape memory nickel-titanium alloy (nitinol) was developed and used in an endovascular thrombectomy device prototype. The microactuator maintains a straight rod shape until an applied current induces electro-resistive (joule) heating, causing the microactuator to transform into a corkscrew shape. The straight-to-corkscrew transformation geometry was chosen to permit endovascular delivery through (straight form) and retrieval of (corkscrew form) a stroke-causing thrombus (blood clot) in the brain. Thermal imaging of the microactuator during actuation in air indicated that the steady-state temperature rise caused by Joule heating varied quadratically with applied current and that actuation occurred near the glass transition temperature of the SMP (86 degrees C. To demonstrate clinical application, the device was used to retrieve a blood clot in a water-filled silicone neurovascular model. Numerical modeling of the heat transfer to the surrounding blood and associated thermal effects on the adjacent artery potentially encountered during clinical use suggested that any thermal damage would likely be confined to localized areas where the microactuator was touching the artery wall. This shape memory mechanical thrombectomy device is a promising tool for treating ischemic stroke without the need for infusion of clot-dissolving drugs. C1 Lawrence Livermore Natl Lab, Med Phys & Biophys Div, Livermore, CA 94550 USA. Lawrence Livermore Natl Lab, New Technol div, Livermore, CA 94550 USA. Univ Calif Davis, Sch Med, Dept Radiol, Sacramento, CA 95817 USA. Kaiser Permanente Med Ctr, Sacramento, CA 95825 USA. RP Small, W (reprint author), Lawrence Livermore Natl Lab, Med Phys & Biophys Div, 7000 E Ave,L-211, Livermore, CA 94550 USA. EM small3@llnl.gov FU NIBIB NIH HHS [R01 EB000462, R01EB000462] NR 40 TC 31 Z9 31 U1 2 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9294 J9 IEEE T BIO-MED ENG JI IEEE Trans. Biomed. Eng. PD SEP PY 2007 VL 54 IS 9 BP 1657 EP 1666 DI 10.1109/TBME.2007.892921 PG 10 WC Engineering, Biomedical SC Engineering GA 204TW UT WOS:000249067900013 PM 17867358 ER PT J AU Ortega, JM Small, W Wilson, TS Benett, WJ Loge, JM Maitland, DJ AF Ortega, Jason M. Small, Ward, IV Wilson, Thomas S. Benett, William J. Loge, Jeffrey M. Maitland, Duncan J. TI A shape memory polymer dialysis needle adapter for the reduction of hemodynamic stress within arteriovenous grafts SO IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING LA English DT Article DE computational fluid dynamics; dialysis needle; shape memory polymer; wall shear stress ID INTIMAL HYPERPLASIA; VASCULAR ACCESS; HEMODIALYSIS; FAILURE AB A deployable, shape memory polymer adapter is investigated for reducing the hemodynamic stress caused by dialysis needle flow impingement within an arteriovenous graft. Computational fluid dynamics simulations of dialysis sessions with and without the adapter demonstrate that the adapter provides a significant decrease in the wall shear stress. Preliminary in vitro flow visualization measurements are made within a graft model following delivery and actuation of a prototype shape memory polymer adapter. Both the simulations and the qualitative flow visualization measurements demonstrate that the adapter reduces the severity of the dialysis needle flow impingement on the vascular access graft. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ortega, JM (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. EM ortegal7@llnl.gov; small3@llnl.gov; wilson97@llnl.gov; benett1@llnl.gov; loge1@llnl.gov; maitland1@llnl.gov FU NIBIB NIH HHS [R01EB000462] NR 8 TC 31 Z9 31 U1 0 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9294 J9 IEEE T BIO-MED ENG JI IEEE Trans. Biomed. Eng. PD SEP PY 2007 VL 54 IS 9 BP 1722 EP 1724 DI 10.1109/TBME.2007.892927 PG 3 WC Engineering, Biomedical SC Engineering GA 204TW UT WOS:000249067900022 PM 17867367 ER PT J AU Chanchani, R Bethke, DT Webb, DB Sandoval, C Wouters, GA AF Chanchani, Rajen Bethke, Donald T. Webb, Denise B. Sandoval, Charlie Wouters, Gregg A. TI Development and RF characterization of high density integrated substrate technology SO IEEE TRANSACTIONS ON COMPONENTS AND PACKAGING TECHNOLOGIES LA English DT Article DE benzocyclobutene (BCB); capacitor; embedded passives; high density interconnect (HDI); inductor; MCM-D; radio frequency (RF) characterization; resistor; substrate; tantalum nitride; tantalum pentoxide AB Advanced micro-systems for national security needs will require miniaturization and integration of radio frequency (RF), digital and analog electronics, optics, and microelectromechanical systems (MEMS) on a single substrate. To meets these demands we have developed a high density integrated substrates technology (HDIST) using Benzocyclobutene (BCB)/copper (Cu) with embedded thin film passive components for RF applications. We have developed processes to fabricate HDIST on Si, Al2O3 and low temperature co-fired ceramic wafers. We have built a multilayer stack of six metal and five BCB layers using 5-mu m and 10-mu m thick photo-definable BCB dielectric and 2- to 3-mu m thick Cu conductor. We have also fabricated embedded inductors, in-plane and in 3-D, ranging in values from 750 pH to 42 nH, embedded TaN thin-film resistors with dc values ranging from 10 Omega to 10 k Omega and embedded capacitors ranging in values from 48 pF to 110 nF. We have designed, fabricated and characterized RF performance of this technology. To meet designed RF circuit characteristics, high dimensional accuracy was needed. We have made process refinement to get dimensional control within +/-0.5 Pm of target dielectric thickness and +/-1.5 pm of target metal line Width. This resulted in measured RF performance matching Simulated (target) performance. The results show that the insertion losses in transmission lines range from 0.025 to 0.052 dB/mm. We have also fabricated and tested two types of RF filters in HDIST structure-Ku band coupled line filter and 2-GHz low pass filter. In addition, we have also incorporated and characterized embedded inductors and capacitors at high frequencies. Overall, RF results show that HDIST is well suited for high density RF circuits. We are currently developing a next generation of miniaturized circuits called Integrated System-On-A-Chip. In this technology, we will use integrated substrate technology to stack wafers in 3-D and make electrical connections through the stacked wafers. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chanchani, R (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM chanchr@sandia.gov; dbethke@sandia.gov; dbwebb@sandia.gov; cesand6@sandia.gov; gawoute@sandia.gov NR 14 TC 2 Z9 2 U1 1 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1521-3331 J9 IEEE T COMPON PACK T JI IEEE Trans. Compon. Packaging Technol. PD SEP PY 2007 VL 30 IS 3 BP 478 EP 485 DI 10.1109/TCAPT.2007.898709 PG 8 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 206VA UT WOS:000249209800016 ER PT J AU Zhao, Q Tong, L Counsil, D AF Zhao, Qing Tong, Lang Counsil, David TI Energy-aware adaptive routing for large-scale ad hoc networks: Protocol and performance analysis SO IEEE TRANSACTIONS ON MOBILE COMPUTING LA English DT Article DE routing protocols; wireless communication; ad hoc networks; energy efficiency ID WIRELESS NETWORKS; MOBILE AB We propose and analyze an energy-aware traffic-adaptive routing strategy for large-scale mobile ad hoc networks (MANETs). Referred to as Energy-Aware GEolocation-aided Routing (EAGER), this protocol optimally blends proactive and reactive strategies for energy efficiency. Specifically, EAGER partitions the network into cells and performs intracell proactive routing and intercell reactive routing. The cell size and the transmission range are optimized analytically. By adjoining cells around hot spots and hot routes in the network, EAGER is capable of handling time-varying and spatially heterogeneous traffic conditions. C1 Univ Calif Davis, Dept Elect & Comp Engn, Davis, CA 95616 USA. Cornell Univ, Sch Elect & Comp Engn, Ithaca, NY 14853 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Zhao, Q (reprint author), Univ Calif Davis, Dept Elect & Comp Engn, 3165 Kemper Hall, Davis, CA 95616 USA. EM qzhao@ece.ucdavis.edu; ltong@ece.cornell.edu; dcounsi@sandia.gov NR 39 TC 13 Z9 17 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1536-1233 EI 1558-0660 J9 IEEE T MOBILE COMPUT JI IEEE. Trans. Mob. Comput. PD SEP PY 2007 VL 6 IS 9 BP 1048 EP 1059 DI 10.1109/TMC.2007.1047 PG 12 WC Computer Science, Information Systems; Telecommunications SC Computer Science; Telecommunications GA 190WE UT WOS:000248090500004 ER PT J AU Ornitaomu, OA Jeong, MK Badiru, AB Hines, JW AF Ornitaomu, Olufemi A. Jeong, Myong K. Badiru, Adedeji B. Hines, J. Wesley TI Online support vector regression approach for the monitoring of motor shaft misalignment and feedwater flow rate SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART C-APPLICATIONS AND REVIEWS LA English DT Article DE data mining; machine health monitoring; nuclear power plant; online condition monitoring systems ID COUPLING MISALIGNMENT; MACHINERY; VIBRATION; PREDICTION; DIAGNOSIS; SYSTEM; TOOL AB Timely and accurate information about incipient faults in online machines will greatly enhance the development of optimal maintenance procedures. The application of support vector regression to machine health monitoring was recently investigated; however, such implementation is based on batch processing of the available data. Therefore, the addition of new sample to the already existing dataset requires that the technique should retrain from scratch. This disadvantage makes the technique unsuitable for online systems that will give real-time information to field engineers so that corrective actions could be taken before there is any damage to the system. This paper presents an application of accurate online support vector regression (AOSVR) approach that efficiently updates a trained predictor whenever a new sample is added to the training set using shaft misalignment and nuclear power plant feedwater flow rate data. The results show that the approach is effective for online machine condition monitoring where it is usually difficult to obtain sufficient training data prior to the installation of the online systems. C1 Oak Ridge Natl Lab, Div Computat Sci & Engn, Oak Ridge, TN 37830 USA. Univ Tennessee, Dept Ind & Informat Engn, Knoxville, TN 37996 USA. Air Force Inst Technol, Dept Syst & Engn Managementt, Wright Patterson AFB, OH 45433 USA. Univ Tennessee, Dept Nucl Engn, Knoxville, TN 37996 USA. RP Ornitaomu, OA (reprint author), Oak Ridge Natl Lab, Div Computat Sci & Engn, Oak Ridge, TN 37830 USA. EM omitaomuoa@oml.gov; mjeong@utk.edu; adedeji.badiru@afit.edu; jhines2@utk.edu NR 41 TC 12 Z9 14 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 1094-6977 J9 IEEE T SYST MAN CY C JI IEEE Trans. Syst. Man Cybern. Part C-Appl. Rev. PD SEP PY 2007 VL 37 IS 5 BP 962 EP 970 DI 10.1109/TMSCC.2007.900648 PG 9 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Interdisciplinary Applications SC Computer Science GA 204DL UT WOS:000249023700020 ER PT J AU Sisneros, R Jones, C Huang, J Gao, JZ Park, BH Samatova, NF AF Sisneros, Robert Jones, Chad Huang, Jian Gao, Jinzhu Park, Byung-Hoon Samatova, Nagiza F. TI A multilevel cache model for runtime optimization of remote visualization SO IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS LA English DT Article DE remote visualization; distributed visualization; performance analysis; caching ID BENCHMARK SUITE AB Remote visualization is an enabling technology aiming to resolve the barrier of physical distance. Although many researchers have developed innovative algorithms for remote visualization, previous work has focused little on systematically investigating optimal configurations of remote visualization architectures. In this paper, we study caching and prefetching, an important aspect of such architecture design, in order to optimize the fetch time in a remote visualization system. Unlike a processor cache or Web cache, caching for remote visualization is unique and complex. Through actual experimentation and numerical simulation, we have discovered ways to systematically evaluate and search for optimal configurations of remote visualization caches under various scenarios, such as different network speeds, sizes of data for user requests, prefetch schemes, cache depletion schemes, etc. We have also designed a practical infrastructure software to adaptively optimize the caching architecture of general remote visualization systems, when a different application is started or the network condition varies. The lower bound of achievable latency discovered with our approach can aid the design of remote visualization algorithms and the selection of suitable network layouts for a remote visualization system. C1 Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. Univ Calif Davis, Dept Comp Sci, Davis, CA 95616 USA. Univ Minnesota, Div Sci & Math, Morris, MN 56267 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Sisneros, R (reprint author), Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. EM sisneros@cs.utk.edu; cejjones@cs.utk.edu; huangj@cs.utk.edu; gaoj@morris.umn.edu; parkbh@ornl.gov; samatovan@ornl.gov RI Gao, Jinzhu/B-4716-2011 NR 21 TC 5 Z9 6 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1077-2626 EI 1941-0506 J9 IEEE T VIS COMPUT GR JI IEEE Trans. Vis. Comput. Graph. PD SEP-OCT PY 2007 VL 13 IS 5 BP 991 EP 1003 DI 10.1109/TVCG.2007.1046 PG 13 WC Computer Science, Software Engineering SC Computer Science GA 188BP UT WOS:000247893800012 PM 17622682 ER PT J AU Yu, X Starke, MR Tolbert, LM Ozpineci, B AF Yu, X. Starke, M. R. Tolbert, L. M. Ozpineci, B. TI Fuel cell power conditioning for electric power applications: a summary SO IET ELECTRIC POWER APPLICATIONS LA English DT Article ID INVERTER; CONVERTER; GENERATION AB Fuel cells are considered to be one of the most promising sources of distributed energy because of their high efficiency, low environmental impact and scalability. Unfortunately, multiple complications exist in fuel cell operation. Fuel cells cannot accept current in the reverse direction, do not perform well with ripple current, have a low output voltage that varies with age and current, respond sluggishly to step changes in load and are limited in overload capabilities. For these reasons, power converters are often necessary to boost and regulate the voltage as a means to provide a stiff applicable DC power source. Furthermore, the addition of an inverter allows for the conversion of DC power to AC for an utility interface or for the application of an AC motor. To help motivate the use of power conditioning for the fuel cell, a brief introduction of the different types, applications and typical electrical characteristics of fuel cells is presented. This is followed by an examination of the various topologies of DC-DC boost converters and inverters used for power conditioning of fuel cells. Several architectures to aggregate multiple fuel cells for high-voltage/high-power applications are also reviewed. C1 Univ Tennessee, Dept Elect & Comp Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Power Elect & Elect Machinery Res Ctr, Oak Ridge, TN 37831 USA. RP Yu, X (reprint author), Univ Tennessee, Dept Elect & Comp Engn, Knoxville, TN 37996 USA. EM tolbertlm@ornl.gov OI Tolbert, Leon/0000-0002-7285-609X NR 38 TC 103 Z9 103 U1 1 U2 6 PU INST ENGINEERING TECHNOLOGY-IET PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1751-8660 J9 IET ELECTR POWER APP JI IET Electr. Power Appl. PD SEP PY 2007 VL 1 IS 5 BP 643 EP 656 DI 10.1049/iet-epa:20060386 PG 14 WC Engineering, Electrical & Electronic SC Engineering GA 216WB UT WOS:000249908600001 ER PT J AU Croft, MC Jisrawi, NM Zhong, Z Holtz, RL Sadananda, K Skaritka, JR Tsakalakos, T AF Croft, Mark C. Jisrawi, Naieh M. Zhong, Zhong Holtz, Ronald L. Sadananda, Kuntimaddi Skaritka, John R. Tsakalakos, Thomas TI Fatigue history and in-situ loading studies of the overload effect using high resolution X-ray strain profiling SO INTERNATIONAL JOURNAL OF FATIGUE LA English DT Article; Proceedings Paper CT 6th International Conference on Fatique Damage of Structural Materials CY SEP 17-22, 2006 CL Hyannis, MA SP Off Naval Res Headquarters, USA Res Lab, Off Naval Res Global DE fatigue; strain; X-ray; synchrotron; overload ID CRACK GROWTH AB High-energy synchrotron X-ray diffraction experiments are used to perform local crack plane strain profiling of 4140 steel compact tension specimens fatigued at constant amplitude, subjected to a single overload cycle, then fatigued some more at constant amplitude. X-ray strain profiling results on a series of samples employing in-situ load cycling are correlated with the crack growth rate (da/dN) providing insight into the da/dN retardation known as the "overload effect". Immediately after the overload, the strain under maximum load is greatly reduced but the range of strain, between zero and maximum load, remains unchanged compared to the pre-overload values. At the point of maximum retardation, it is the strain range that is greatly reduced while the maximum-load strain has begun to recover to the pre-overload value. For a sample that has recovered to approximately half of the original da/dN value following the overload, the strain at maximum load is fully recovered while the strain range, though partially recovered, is still substantially reduced. The dominance of the strain range in the overload effect is clearly indicated. Subject to some assumptions, strong quantitative support for a crack growth rate driving force of the suggested form [(K-max)(1-p)(Delta K)(p)](gamma) is found. A dramatic nonlinear load dependence in the spatial distribution of the strain at maximum retardation is also demonstrated: at low load the response is dominantly at the overload position; whereas at high loads it is dominantly at the crack tip position. This transfer of load response away from the crack tip to the overload position appears fundamental to the overload effect for high R-ratio fatigue as studied here. (C) 2007 Elsevier Ltd. All rights reserved. C1 Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Rutgers State Univ, Dept Ceram, Piscataway, NJ 08854 USA. Univ Sharjah, Dept Basic Sci, Sharjah, U Arab Emirates. Naval Res Lab, Washington, DC 20375 USA. Tech Data Anal Inc, Falls Church, VA 22046 USA. RP Croft, MC (reprint author), Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. EM croft@physics.rutgers.edu NR 15 TC 25 Z9 25 U1 0 U2 8 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-1123 J9 INT J FATIGUE JI Int. J. Fatigue PD SEP-NOV PY 2007 VL 29 IS 9-11 BP 1726 EP 1736 DI 10.1016/j.ijfatigue.2007.01.016 PG 11 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 215YO UT WOS:000249845100015 ER PT J AU Huang, EW Clausen, B Wang, Y Choo, H Liaw, PK Benson, ML Pike, LM Klarstrom, DL AF Huang, E.-Wen Clausen, Bjorn Wang, Yandong Choo, Hahn Liaw, Peter K. Benson, Michael L. Pike, Lee M. Klarstrom, Dwaine L. TI A neutron-diffraction study of the low-cycle fatigue behavior of HASTELLOY (R) C-22HS (TM) alloy SO INTERNATIONAL JOURNAL OF FATIGUE LA English DT Article; Proceedings Paper CT 6th International Conference on Fatique Damage of Structural Materials CY SEP 17-22, 2006 CL Hyannis, MA SP Off Naval Res Headquarters, USA Res Lab, Off Naval Res Global DE low-cycle fatigue; in situ neutron diffraction; cyclic hardening; cyclic softening ID LATTICE STRAIN EVOLUTION; INTERGRANULAR STRESSES; STAINLESS-STEEL; DEFORMATION; POLYCRYSTAL; REFINEMENT AB The HASTELLOY (R) C-22HS (TM) alloy is a face-centered cubic (fcc), nickel-based, corrosion-resistant superalloy. In the present study, the low-cycle-fatigue behaviors of the alloy were examined by in situ neutron diffraction at room temperature. The fatigue parameters included a total strain range of Delta epsilon=2% and a strain ratio of R = -1 (R = epsilon(min)/epsilon(max), where epsilon(min) in and epsilon(max) are the applied minimum and maximum strains, respectively). The effect of cyclic deformation on the lattice strains was studied as a function of cyclic straining. The cyclic hardening and softening behaviors during fatigue is discussed in light of the relationship between the peak widths and lattice strains. (C) 2007 Elsevier Ltd. All rights reserved. C1 Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. Los Alamos Natl Lab, Los Alamos Neutron Sci Ctr, Los Alamos, NM 87545 USA. Haynes Int Inc, Kokomo, IN 46904 USA. RP Huang, EW (reprint author), Univ Tennessee, Dept Mat Sci & Engn, 434 Dougherty Hall, Knoxville, TN 37996 USA. EM ebuang1@utk.edu RI Huang, E-Wen/A-7509-2009; Choo, Hahn/A-5494-2009; Huang, E-Wen/A-5717-2015; Clausen, Bjorn/B-3618-2015 OI Choo, Hahn/0000-0002-8006-8907; Huang, E-Wen/0000-0003-4986-0661; Clausen, Bjorn/0000-0003-3906-846X NR 27 TC 11 Z9 11 U1 1 U2 10 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-1123 J9 INT J FATIGUE JI Int. J. Fatigue PD SEP-NOV PY 2007 VL 29 IS 9-11 BP 1812 EP 1819 DI 10.1016/j.ijfatigue.2007.01.025 PG 8 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 215YO UT WOS:000249845100025 ER PT J AU Yelick, K Hilfinger, P Graham, S Bonachea, D Su, J Kamil, A Datta, K Colella, P Wen, T AF Yelick, K. Hilfinger, P. Graham, S. Bonachea, D. Su, J. Kamil, A. Datta, K. Colella, P. Wen, T. TI Parallel languages and compilers: Perspective from the Titanium experience SO INTERNATIONAL JOURNAL OF HIGH PERFORMANCE COMPUTING APPLICATIONS LA English DT Article DE Titanium; parallel; language; compiler ID IMPLEMENTATION; DESIGN AB We describe the rationale behind the design of key features of Titanium-an explicitly parallel dialect of Java for high-performance scientific programming-and our experiences in building applications with the language. Specifically, we address Titanium's partitioned global address space model, single program multiple data parallelism support, multi-dimensional arrays and array-index calculus, memory management, immutable classes (class-like types that are value types rather than reference types), operator overloading, and generic programming. We provide an overview of the Titanium compiler implementation, covering various parallel analyses and optimizations, Titanium runtime technology and the GASNet network communication layer. We summarize results and lessons learned from implementing the NAS parallel benchmarks, elliptic and hyperbolic solvers using adaptive mesh refinement, and several applications of the immersed boundary method. C1 Univ Calif Berkeley, Div Comp Sci, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Yelick, K (reprint author), Univ Calif Berkeley, Div Comp Sci, Berkeley, CA 94720 USA. EM YELICK@CS.BERKELEY.EDU NR 64 TC 9 Z9 9 U1 0 U2 0 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 1094-3420 J9 INT J HIGH PERFORM C JI Int. J. High Perform. Comput. Appl. PD FAL PY 2007 VL 21 IS 3 BP 266 EP 290 DI 10.1177/1094342007078449 PG 25 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA 202FH UT WOS:000248886900003 ER PT J AU Luszczek, P Dongarra, J AF Luszczek, Piotr Dongarra, Jack TI High performance development for high end computing with Python language wrapper (PLW) SO INTERNATIONAL JOURNAL OF HIGH PERFORMANCE COMPUTING APPLICATIONS LA English DT Article DE Phython compilation; static typing; high performance parallel computing; rapid application development; scripting languages ID LINEAR ALGEBRA SUBPROGRAMS; MODEL IMPLEMENTATION; TEST PROGRAMS; EXTENDED SET; SOFTWARE AB This paper presents a design and implementation of a system that leverages interactive scripting environment to the needs of scientific computing. The system allows seamless translation of high level script codes to highly optimized native language executables that can be ported to parallel systems with high performance hardware and potential lack of the scripting language interpreter. Performance results are given to show various usage scenarios that differ in terms of invested programmer's effort and resulting performance gains. C1 Univ Tennessee Knoxville, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Luszczek, P (reprint author), Univ Tennessee Knoxville, Knoxville, TN 37996 USA. NR 38 TC 0 Z9 0 U1 1 U2 3 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 1094-3420 EI 1741-2846 J9 INT J HIGH PERFORM C JI Int. J. High Perform. Comput. Appl. PD FAL PY 2007 VL 21 IS 3 BP 360 EP 369 DI 10.1177/1094342007078444 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA 202FH UT WOS:000248886900007 ER PT J AU Kopasz, JP AF Kopasz, John P. TI Fuel cells and odorants for hydrogen SO INTERNATIONAL JOURNAL OF HYDROGEN ENERGY LA English DT Article DE hydrogen; odorant; fuel cell; hydrogen storage AB Odorants have been proposed as a reliable, inexpensive means to enable leak detection for hydrogen systems and increase public safety. However, traditional odorants cause problems for fuel cell systems. This paper examines the use of odorants for fuel cell systems, including the hydrogen storage. Current odorants and potential odorants have negative impacts on fuel cell performance. Odorants also appear to be problematic for most of the advanced hydrogen storage options. If odorants are used, the odorants will probably need to be removed from the hydrogen prior to the storage medium. Current hydrogen detectors are more reliable than the odorant-human detection system and should provide increased safety. (C) 2006 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Kopasz, JP (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM Kopasz@cmt.anl.gov NR 10 TC 4 Z9 4 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-3199 J9 INT J HYDROGEN ENERG JI Int. J. Hydrog. Energy PD SEP PY 2007 VL 32 IS 13 BP 2527 EP 2531 DI 10.1016/j.ijhydene.2006.11.001 PG 5 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA 219CS UT WOS:000250062900057 ER PT J AU Towns, B Skolnik, EG Miller, J Schefer, RW Keller, JO AF Towns, B. Skolnik, E. G. Miller, J. Schefer, R. W. Keller, J. O. TI Analysis of the benefits of carbon credits to hydrogen addition to midsize gas turbine feedstocks SO INTERNATIONAL JOURNAL OF HYDROGEN ENERGY LA English DT Article DE hydrogen; combustion; emissions; gas turbines AB The addition of hydrogen to the natural gas feedstocks of midsize (30-150 MW) gas turbines was analyzed as a method of reducing nitrogen oxides (NOx) and CO2 emissions. In particular, the costs of hydrogen addition were evaluated against the combined costs for other current NOx and CO2 emissions control technologies for both existing and new systems to determine its benefits and market feasibility. Markets for NOx emissions credits currently exist in California and the Northeast States and are expected to grow. Although regulations are not currently in place in the United States, several other countries have implemented carbon tax and carbon credit programs. The analysis thus assumes that the United States adopts future legislation similar to these programs. Therefore, potential sale of emissions credits for volunteer retrofits was also included in the study. It was found that hydrogen addition is a competitive alternative to traditional emissions abatement techniques under certain conditions. The existence of carbon credits shifts the system economics in favor of hydrogen addition. (c) 2007 Published by Elsevier Ltd on behalf of the International Association for Hydrogen Energy. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Energetics Inc, Washington, DC 20024 USA. RP Schefer, RW (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. EM rwsche@sandia.gov RI Schefer, Jurg/G-3960-2012 NR 14 TC 3 Z9 3 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-3199 J9 INT J HYDROGEN ENERG JI Int. J. Hydrog. Energy PD SEP PY 2007 VL 32 IS 14 SI SI BP 3093 EP 3099 DI 10.1016/j.ijhydene.2007.01.021 PG 7 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA 222HP UT WOS:000250287300057 ER PT J AU Futrell, JH Smith, R AF Futrell, Jean H. Smith, Richard TI Jean H Futrell - Foreword SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Biographical-Item C1 Pacific NW Natl Lab, Richland, WA 99354 USA. RP Futrell, JH (reprint author), Pacific NW Natl Lab, 3335 Q Av,MSIN K8-98, Richland, WA 99354 USA. EM dick.smith@pnl.gov NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD SEP 1 PY 2007 VL 265 IS 2-3 BP 75 EP 79 DI 10.1016/j.ijms.2007.06.022 PG 5 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 202XA UT WOS:000248936500001 ER PT J AU Yang, Z Hadjar, O Laskin, J AF Yang, Zhibo Hadjar, Omar Laskin, Julia TI Effect of the surface morphology on the energy transfer in ion-surface collisions SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE surface-induced dissociation; protonated peptide; energy transfer; surface morphology; FT-ICR MS ID ASSEMBLED MONOLAYER SURFACES; RESONANCE MASS-SPECTROMETRY; FT-ICR MS; INDUCED DISSOCIATION; PEPTIDE IONS; PROTONATED DIGLYCINE; POLYATOMIC IONS; MOLECULAR-IONS; ORGANIC MONOLAYERS; LIQUID SURFACE AB Time- and energy-resolved surface-induced dissociation (SID) of singly protonated des-Arg(1) -bradykinin (PPGFSPFR) combined with RRKM modeling was used to explore the effect of surface morphology on the energy transfer in collisions of large ions with surfaces. Experiments were performed in a Fourier Transform ion cyclotron resonance mass spectrometer (FT-ICR MS) specially configured for SID studies. Mass-selected and vibrationally relaxed ions were collided with three diamond surfaces of varying degree of roughness along the surface normal. The results demonstrate that internal energy distributions resulting from collisions of large ions with surfaces are rather independent of the surface morphology: the translational to vibrational (T -> V) energy transfer efficiency is 19.5 +/- 0.5% for all three diamond surfaces. However, the scattered ion signal increases by a factor of 2 with decrease in the degree of roughness of the SID target suggesting that smooth diamond surfaces are better targets for analytical applications. Published by Elsevier B.V. C1 Pacific NW Natl Lab, Div Chem & Mat Sci, Fund Sci Directorate, Richland, WA 99352 USA. RP Laskin, J (reprint author), Pacific NW Natl Lab, Div Chem & Mat Sci, Fund Sci Directorate, POB 999,K8-88, Richland, WA 99352 USA. EM Julia.Laskin@pni.gov RI Yang, Zhibo/E-4088-2010; Laskin, Julia/H-9974-2012 OI Laskin, Julia/0000-0002-4533-9644 NR 42 TC 4 Z9 4 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD SEP 1 PY 2007 VL 265 IS 2-3 BP 124 EP 129 DI 10.1016/j.ijms.2007.01.018 PG 6 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 202XA UT WOS:000248936500005 ER PT J AU Laskin, J Wang, P Hadjar, O Futrell, JH Alvarez, J Cooks, ZG AF Laskin, Julia Wang, Peng Hadjar, Omar Futrell, Jean H. Alvarez, Jormarie Cooks, Z. Graham TI Charge retention by peptide ions soft-landed onto self-assembled monolayer surfaces SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE surface-induced dissociation; ion soft-landing; ion-surface collisions; peptides; self-assembled monolayers; secondary ion mass spectrometry (SIMS); Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) ID COLLISION-INDUCED DISSOCIATION; RESONANCE MASS-SPECTROMETER; CYCLOTRON RESONANCE; PROTONATED PEPTIDES; PREPARATIVE SOFT; POLYATOMIC IONS; BOMBARDMENT; ENERGETICS; CATIONS; STATE AB Soft-landing of singly and doubly protonated peptide ions onto three self-assembled monolayer surfaces (SAMs) was performed using a novel ion deposition instrument constructed in our laboratory and a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) specially designed for studying collisions of large ions with surfaces. Modified surfaces were analyzed using in situ 2keV Cs+ secondary ion mass spectrometry or ex situ 15 keV Ga+ time-of-flight-secondary ion mass spectrometry (ToF-SIMS). The results demonstrate that a fraction of multiply protonated peptide ions retain more than one proton following soft-landing on the FSAM surface. It is shown that the [M+2H](2+) ions observed in FT-ICR SIMS spectra are produced by desorption of multiply charged ions from the surface, while re-ionization of singly protonated ions or neutral peptides is a source of [M+2H](2+) ions in ToF-SIMS spectra. Differences in neutralization efficiency of soft-landed ions following exposure of surfaces to laboratory air has a measurable effect on the results of ex situ ToF-SIMS analysis of soft-landed ions on SAM surfaces. (C) 2007 Elsevier B.V. All rights reserved. C1 Pacific NW Natl Lab, Fundamental Sci Div, Fundamental Sci Directorate, Richland, WA 99352 USA. Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. RP Laskin, J (reprint author), Pacific NW Natl Lab, Fundamental Sci Div, Fundamental Sci Directorate, POB 999,K8-88, Richland, WA 99352 USA. EM Julia.Laskin@pnl.gov RI Laskin, Julia/H-9974-2012; Cooks, R/G-1051-2015 OI Laskin, Julia/0000-0002-4533-9644; Cooks, R/0000-0002-9581-9603 NR 37 TC 26 Z9 26 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD SEP 1 PY 2007 VL 265 IS 2-3 BP 237 EP 243 DI 10.1016/j.ijms.2007.02.013 PG 7 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 202XA UT WOS:000248936500018 ER PT J AU Page, JS Tang, K Smith, RD AF Page, Jason S. Tang, Keqi Smith, Richard D. TI An electrodynamic ion funnel interface for greater sensitivity and higher throughput with linear ion trap mass spectrometers SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE electrospray ionization; electrodynamic ion funnel; linear ion trap; ion accumulation time; sensitivity ID ELECTROSPRAY-IONIZATION; GAIN-CONTROL; TRANSMISSION; PROTEOME AB An electrospray ionization interface incorporating an electrodynamic ion funnel has been designed and implemented on a linear ion trap mass spectrometer (Thermo Electron, LTQ). We found ion transmission to be greatly improved by replacing the standard capillary-skimmer interface with the capillary-ion funnel interface. An infusion study using a serial dilution of a reserpine solution showed that ion injection (accumulation) times to fill the ion trap at a given automatic gain control (AGC) target value were reduced by similar to 90% which resulted in an similar to 10-fold increase in peak intensities. In liquid chromatography tandem MS (LC-MS/MS) experiments performed using a global protein digest sample from the bacterium, Shewanella oneidensis, more peptides and proteins were identified when the ion funnel interface was used in place of the standard interface. This improvement was most pronounced at lower sample concentrations, where extended ion accumulation times are required, resulting in an similar to 2-fold increase in the number of protein identifications. Implementation of the ion funnel interface on a LTQ Fourier transform (FT) mass spectrometer showed a similar to 25-50% reduction in spectrum acquisition time. The duty cycle improvement in this case was due to the ion accumulation event contributing a larger portion to the total spectrum acquisition time. (C) 2007 Elsevier B.V. All rights reserved. C1 Pacific NW Natl Lab, Div Biol Sci, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Div Biol Sci, POB 999,MS K8-98, Richland, WA 99352 USA. EM rds@pnl.gov RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 23 TC 15 Z9 16 U1 4 U2 22 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD SEP 1 PY 2007 VL 265 IS 2-3 BP 244 EP 250 DI 10.1016/j.ijms.2007.02.032 PG 7 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 202XA UT WOS:000248936500019 ER PT J AU Kalinin, SV Jesse, S Rodriguez, BJ Seal, K Baddorf, AP Zhao, T Chu, YH Ramesh, R Eliseev, EA Morozovska, AN Mirman, B Karapetian, E AF Kalinin, Sergei V. Jesse, Stephen Rodriguez, Brian J. Seal, Katyayani Baddorf, Arthur P. Zhao, Tong Chu, Y. H. Ramesh, Ramamoorthy Eliseev, Eugene A. Morozovska, Anna N. Mirman, B. Karapetian, Edgar TI Recent advances in electromechanical Imaging on the nanometer scale: Polarization dynamics in ferroelectrics, biopolymers, and liquid Imaging SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS LA English DT Review DE piezoresponse force microscopy; ferroelectric; multiferroic; atomic force microscopy; switching spectroscopy; electromechanics; polymers; biological imaging; liquid imaging ID PIEZORESPONSE FORCE MICROSCOPY; THIN-FILMS; PIEZOELECTRICITY; INDENTATION; SURFACE; BONE; TITANATE; POLARITY; DOMAINS AB Coupling between electrical and mechanical phenomena is ubiquitous in nature, with examples ranging from piezoelectricity in polar perovskites and chemical bonds to complex pathways of electromechanical transformations underpinning the functionality of electromotor proteins, cells, and tissues. Piezoresponse force microscopy (PFM) had originally emerged as a technique to study electromechanical phenomena in ferroelectric perovskites on the nanoscale. In recent years, the applicability of PFM for studying a broad range of non-ferroelectric polar materials has been demonstrated, necessitating further development of the technique, including theory of the image formation mechanism as well as probe and controller development. Here, we review the basic principles of PFM and summarize some of the recent advances, including switching spectroscopy, mapping of polarization dynamics in ferroelectric and multiferroic nanostructures, imaging of biopolymers in calcified and connective tissues and PFM in liquid environments. C1 Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Ctr Nanophase Mat Sci, Oak Ridge, TN 37831 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Natl Acad Sci Ukraine, UA-03028 Kiev, Ukraine. Suffolk Univ, Dept Math & Comp Sci, Boston, MA 02114 USA. RP Kalinin, SV (reprint author), Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. EM sergei2@ornl.gov RI Ying-Hao, Chu/A-4204-2008; Kalinin, Sergei/I-9096-2012; Rodriguez, Brian/A-6253-2009; Jesse, Stephen/D-3975-2016; Baddorf, Arthur/I-1308-2016 OI Ying-Hao, Chu/0000-0002-3435-9084; Kalinin, Sergei/0000-0001-5354-6152; Rodriguez, Brian/0000-0001-9419-2717; Jesse, Stephen/0000-0002-1168-8483; Baddorf, Arthur/0000-0001-7023-2382 NR 36 TC 10 Z9 12 U1 2 U2 36 PU INST PURE APPLIED PHYSICS PI TOKYO PA 5F YUSHIMA BLDG, 2-31-22 YUSHIMA, BUNKYO-KU, TOKYO, 113-0034, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Brief Commun. Rev. Pap. PD SEP PY 2007 VL 46 IS 9A BP 5674 EP 5685 DI 10.1143/JJAP.46.5674 PG 12 WC Physics, Applied SC Physics GA 212WA UT WOS:000249626400002 ER PT J AU Watanabe, S Ishikawa, SN Takeda, S Odaka, H Tanaka, T Takahashi, T Nakazawa, K Yamazato, M Higa, A Kaneku, S AF Watanabe, Shin Ishikawa, Shin-nosuke Takeda, Shin'ichiro Odaka, Hirokazu Tanaka, Takaaki Takahashi, Tadayuki Nakazawa, Kazuhiro Yamazato, Masaaki Higa, Akira Kaneku, Sakari TI New CdTe pixel gamma-ray detector with pixelated Al schottky anodes SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS LA English DT Article DE gamma-ray detector; cadmium telluride (CdTe); pixel detector ID X-RAY AB We developed a new At Schottky CdTe pixel detector and measured its spectral performance. It has pixelated anodes made of aluminum and a common cathode made of platinum. Because of the low leakage current and the high bias voltage owing to the Schottky diode characteristic and the anode pixel configuration, a good spectral performance including a high energy resolution was achieved. When the pixel detector with a thickness of 0.75 mm was subjected to a bias voltage of 400 V and was operated at -20 degrees C, the full-width-half-maximum (FWHM) energy resolution of 1.1 and 1.8keV at 59.5 and 122keV, respectively, were successfully obtained. The spectral performance obtained with the At Schottky CdTe pixel detector exceeded that obtained with the conventional In Schottky CdTe pixel detector, which has an In common anode and Pt pixelated cathodes, under the same operating conditions. C1 Japan Aerosp Expolrat Agcy, Inst Space & Astronaut Sci, Kanagawa 2298510, Japan. Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. Univ Ryukyus, Fac Engn, Okinawa 9300213, Japan. ACRORAD Co Ltd, Okinawa 9042234, Japan. RP Watanabe, S (reprint author), Japan Aerosp Expolrat Agcy, Inst Space & Astronaut Sci, 3-1-1 Yoshinodai, Kanagawa 2298510, Japan. EM watanabe@astro.isas.jaxa.jp NR 10 TC 35 Z9 35 U1 0 U2 3 PU INST PURE APPLIED PHYSICS PI TOKYO PA 5F YUSHIMA BLDG, 2-31-22 YUSHIMA, BUNKYO-KU, TOKYO, 113-0034, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Brief Commun. Rev. Pap. PD SEP PY 2007 VL 46 IS 9A BP 6043 EP 6045 DI 10.1143/JJAP.46.6043 PG 3 WC Physics, Applied SC Physics GA 212WA UT WOS:000249626400074 ER PT J AU Zhang, XH Zhu, YT Rigsbee, M Suryanarayana, C Wang, HY Liu, CT AF Zhang, Xinghang Zhu, Yuntian Rigsbee, Mike Suryanarayana, C. Wang, Haiyan Liu, C. T. TI Mechanical Behavior of nanostructured materials symposium honoring Carl Koch SO JOM LA English DT Editorial Material C1 Texas A&M Univ, College Stn, TX 77843 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. N Carolina State Univ, Raleigh, NC 27695 USA. Univ Cent Florida, Orlando, FL 32816 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Zhang, XH (reprint author), Texas A&M Univ, College Stn, TX 77843 USA. RI Suryanarayana, C/B-9314-2008; Wang, Haiyan/P-3550-2014 OI Wang, Haiyan/0000-0002-7397-1209 NR 0 TC 0 Z9 0 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-US JI JOM PD SEP PY 2007 VL 59 IS 9 BP 49 EP 49 DI 10.1007/s11837-007-0116-2 PG 1 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 208LZ UT WOS:000249322100007 ER PT J AU Kennedy, MS Moody, NR Bahr, DE AF Kennedy, M. S. Moody, N. R. Bahr, D. E. TI The aging of metallic thin films: delamination, strain relaxation, and diffusion SO JOM LA English DT Article; Proceedings Paper CT Symposium on Mechanical Behavior of Nanostructured Materials held TMS 2007 Annual Meeting CY FEB 26-MAR 01, 2007 CL Orlando, FL SP TSM ID ADHESION MEASUREMENTS; BEND ADHESION; FRACTURE; COPPER AB The reliability of thin film systems is important to the continued development of microelectronics, micro-electromechanical systems, and conventional industries. Most often, the reliability of devices in these systems is tied to the ability of the films to remain adhered to substrates during the component lifetime. This research summary looks at the aging of gold thin films and their subsequent fracture from silicon substrates. The mechanical integrity of these films, controlled by the adhesion energy of the interface, is shown to be influenced by strain relaxation and diffusion. C1 Washington State Univ, Pullman, WA 99164 USA. Sandia Natl Labs, Livermore, CA USA. RP Kennedy, MS (reprint author), Washington State Univ, Pullman, WA 99164 USA. EM bahr@mme.wsu.edu RI Bahr, David/A-6521-2012 OI Bahr, David/0000-0003-2893-967X NR 28 TC 1 Z9 1 U1 1 U2 3 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-US JI JOM PD SEP PY 2007 VL 59 IS 9 BP 50 EP 53 DI 10.1007/s11837-007-0117-1 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 208LZ UT WOS:000249322100008 ER PT J AU Sun, Y Ye, J Shan, Z Minor, AM Balk, TJ AF Sun, Ye Ye, Jia Shan, Zhiwei Minor, Andrew M. Balk, T. John TI The mechanical Behavior of nanoporous gold thin films SO JOM LA English DT Article; Proceedings Paper CT Symposium on Mechanical Behavior of Nanostructured Materials held TMS 2007 Annual Meeting CY FEB 26-MAR 01, 2007 CL Orlando, FL SP TSM ID IN-SITU NANOINDENTATION; YIELD STRENGTH; AU AB Thin films of nanoporous noble metals exhibit an interconnected, porous structure with ligament widths and pores on the order of 10 nm or higher. In this study, thin film stress measurements and in-situ nanoindentation in a transmission-electron microscope were performed to investigate the effects of nanoscale geometric confinement on the mechanical properties of metals and on dislocation-mediatedplasticity. Although some films exhibit macroscopic cracking, the deformation of individual ligaments is completely ductile and clearly involves dislocation activity, even in 10 nm wide ligaments. The stresses generated in these films during thermal cycling correspond to bulk stresses that approach the theoretical strength of the metal. Film stress exhibits a dependence on film thickness, even though the ligament width is much smaller and would presumably govern deformation. C1 Univ Kentucky, Lexington, KY 40536 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. Hysitron Inc, Minneapolis, MN USA. RP Sun, Y (reprint author), Univ Kentucky, Lexington, KY 40536 USA. EM balk@engr.uky.edu RI Sun, Ye/F-8560-2010 NR 19 TC 33 Z9 33 U1 2 U2 21 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-US JI JOM PD SEP PY 2007 VL 59 IS 9 BP 54 EP 58 DI 10.1007/s11837-007-0118-0 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 208LZ UT WOS:000249322100009 ER PT J AU Misra, A Demkowicz, MJ Zhang, X Hoagland, RG AF Misra, A. Demkowicz, M. J. Zhang, X. Hoagland, R. G. TI The radiation damage tolerance of ultra-high strength nanolayered composites SO JOM LA English DT Article; Proceedings Paper CT Symposium on Mechanical Behavior of Nanostructured Materials held TMS 2007 Annual Meeting CY FEB 26-MAR 01, 2007 CL Orlando, FL SP TSM ID EMBEDDED-ATOM METHOD; NANOSTRUCTURED MATERIALS; CU/NB MULTILAYERS; IRRADIATION; MECHANISMS; DEFECTS; METALS; HE AB Interfaces act as obstacles to slip and sinks for radiation-induced defects. Hence, nanolayered composites that contain a large volume fraction of inter-faces provide over an order of magnitude increase in strength and enhanced radiation damage tolerance compared to bulk materials. This paper shows the experimental and atomistic modeling results from a Cu-Nb nanolayered composite to highlight the roles of nanostructuring length scales and the response of interfaces to ion collision cascades in designing composite materials radiation damage tolerance. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. RP Misra, A (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM amisra@lanl.gov RI Hoagland, Richard/G-9821-2012; Misra, Amit/H-1087-2012; Zhang, Xinghang/H-6764-2013 OI Zhang, Xinghang/0000-0002-8380-8667 NR 19 TC 210 Z9 211 U1 13 U2 89 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-US JI JOM PD SEP PY 2007 VL 59 IS 9 BP 62 EP 65 DI 10.1007/s11837-007-0120-6 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 208LZ UT WOS:000249322100011 ER PT J AU Zelenyuka, A Imre, D Cuadra-Rodriguez, LA Ellison, B AF Zelenyuka, Alla Imre, Dan Cuadra-Rodriguez, Luis A. Ellison, Barney TI Measurements and interpretation of the effect of a soluble organic surfactant on the density, shape and water uptake of hygroscopic particles SO JOURNAL OF AEROSOL SCIENCE LA English DT Article DE soluble organic surfactant; hygroscopic properties; density; particle shape ID SODIUM DODECYL-SULFATE; AEROSOL-PARTICLES; ATMOSPHERIC AEROSOL; DICARBOXYLIC-ACIDS; AMMONIUM-SULFATE; CHLORIDE; GROWTH; DELIQUESCENCE; ELECTROLYTES; MORPHOLOGY AB A large fraction of atmospheric particles are composed of hygroscopic salts that are mixed with variety of organic molecules, of which surfactants represent an important and interesting class. We present an experimental study of the effect of mixing a soluble surfactant with two hygroscopic salts on particle density, shape and water uptake. We show that the measured densities as a function of particle compositions provide evidence that the surfactant retains water even at very low RH and that its density changes with concentration and is significantly different from that of the anhydrous crystal. When this behavior is taken into account to calculate the effect of surfactant on particle hygroscopicity, the water uptake data can be quantitatively understood. The vacuum aerodynamic size distributions indicate that drying particles with intermediate surfactant concentrations produces a range of particle types, whose properties can be altered by heating. (C) 2007 Elsevier Ltd. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99354 USA. Imre Consulting, Richland, WA 99352 USA. Univ Colorado, Boulder, CO 80309 USA. RP Zelenyuka, A (reprint author), Pacific NW Natl Lab, Richland, WA 99354 USA. EM alla.zelenyuk@pnl.gov NR 31 TC 13 Z9 14 U1 0 U2 18 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0021-8502 EI 1879-1964 J9 J AEROSOL SCI JI J. Aerosol. Sci. PD SEP PY 2007 VL 38 IS 9 BP 903 EP 923 DI 10.1016/j.jaerosci.2007.06.006 PG 21 WC Engineering, Chemical; Engineering, Mechanical; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 224TP UT WOS:000250469600001 ER PT J AU Weiss, JD AF Weiss, Jonathan D. TI Magnetic force and thermal expansion as failure mechanisms of electrothermal MEMS actuators under electrostatic discharge testing SO JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME LA English DT Article DE electrothermal actuator; micromechanics; failure analysis; magnetic forces; thermal expansion; buckling of beams ID BEAM AB Like microelectronic circuits, microelectromechanical systems (MEMS) devices are susceptible to damage by electrostatic discharge (ESD). At Sandia National Laboratories, polysilicon electrothermal MEMS actuators have been subjected to ESD pulses to examine that susceptibility. Failures, in the form of cracks at points of high stress concentration, occurred that could not be explained by thermal degradation of the polysilicon caused by excessive heating, or by excessive displacement of the legs of the actuator of the same nature that occur in normal operation. One hypothesis presented in this paper is that the internal magnetic forces between the legs of the actuator resulting from the ESD-associated high current pulses, might produce vibrations of amplitude sufficient to produce these cracks. However, a dynamic analysis based on simple beam theory indicated that such cracks are unlikely to occur, except under rather extreme conditions. On the other hand, these same current pulses also cause resistive heating of the legs and, therefore, thermally induced compression that can lead to buckling. Buckling stresses, particularly when augmented by magnetic forces, can readily explain failure. Both the magnetic and thermal analyses were performed using the human body model and the machine model of ESD. A justification for ignoring shuttle motion and eddy currents induced in the substrate during the ESD pulse is presented, as well. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Weiss, JD (reprint author), Sandia Natl Labs, POB 5800,Mail Stop 1081, Albuquerque, NM 87185 USA. EM jdweiss@sandia.gov NR 17 TC 0 Z9 0 U1 0 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0021-8936 J9 J APPL MECH-T ASME JI J. Appl. Mech.-Trans. ASME PD SEP PY 2007 VL 74 IS 5 BP 996 EP 1005 DI 10.1115/1.2723813 PG 10 WC Mechanics SC Mechanics GA 218QP UT WOS:000250030300019 ER PT J AU Biloiu, C Scime, EE Biloiu, IA Sun, X AF Biloiu, Costel Scime, Earl E. Biloiu, Ioana A. Sun, Xuan TI Nitrogen dissociation degree in the diffusion region of a helicon plasma source obtained by atomic lines to molecular band intensities ratio SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID OPTICAL-EMISSION SPECTROSCOPY; HIGH-TEMPERATURE LIMITATIONS; IMMERSION ION-IMPLANTATION; ELECTRON-IMPACT EXCITATION; NITRIDE THIN-FILMS; GLOW-DISCHARGE; BEAM EPITAXY; CROSS-SECTIONS; EINSTEIN COEFFICIENTS; TRANSITION-PROBABILITIES AB Estimates of the dissociation degree in the diffusion region of a nitrogen helicon plasma source based on optical emission spectroscopy and Langmuir probe measurements are presented. The estimation procedure relies on measurements of the ratios of the intensities of the atomic triplet 3p S-4(0)-> 3s P-4 (742.36, 744.23, and 746.83 nm) to the intensity of the 4-2 band of the first positive system (A (3)Sigma(+)(u)-> B (3)Pi(g)) at 750.39 nm and the measured relative vibrational distribution of the B (3)Pi(g) state. The electron energy distribution function, obtained from the second derivative of the Langmuir probe characteristic, and published excitation cross sections are used to calculate the electron-impact excitation rate coefficients-which are then compared to the atomic line and molecular band intensities to calculate the dissociation degree. For two distinct operating regimes, capacitively and inductively coupled, dissociation fractions of 5% and 13% are obtained in the expansion region of a 10 mTorr, 500 W, 10.74 MHz helicon generated nitrogen plasma. The dissociation degree results suggest that the helicon source can provide excited molecular species for plasma assisted molecular beam epitaxy of III-group nitrides. (C) 2007 American Institute of Physics. C1 Varian Semicond Equip Assoc, Gloucester, MA 01930 USA. W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Biloiu, C (reprint author), Varian Semicond Equip Assoc, 35 Dory Rd, Gloucester, MA 01930 USA. EM costel.biloiu@vsea.com RI Biloiu, Costel/O-2562-2013 NR 61 TC 7 Z9 7 U1 1 U2 17 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD SEP 1 PY 2007 VL 102 IS 5 AR 053303 DI 10.1063/1.2777998 PG 11 WC Physics, Applied SC Physics GA 210RU UT WOS:000249474100014 ER PT J AU Card, JC Cannon, RM Saiz, E Tomsia, AP Ritchie, RO AF Card, J. C. Cannon, R. M. Saiz, E. Tomsia, A. P. Ritchie, R. O. TI On the physics of moisture-induced cracking in metal-glass (copper-silica) interfaces SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID STRESS-CORROSION CRACKING; STATIC FATIGUE; ALUMINA INTERFACES; LAYERED STRUCTURES; VITREOUS SILICA; FRACTURE; GROWTH; TOUGHNESS; ADHESION; SYSTEMS AB Environmentally dependent subcritical crack growth, or stress-corrosion cracking, along ceramic-metal interfaces is studied for the silica glass-copper system. Tests were conducted in various gaseous and liquid environments in order to determine their relative effects on stress-corrosion cracking and to gain some insight into the mechanisms that control interfacial crack growth. In agreement with previous studies, interfacial crack-growth rates were found to vary by orders of magnitude depending on the moisture content in gaseous environments. Water and several organic liquids, namely n-butanol, methanol, and N-methylformamide, were also found to promote stress-corrosion cracking. Specifically, crack-growth behavior was found to be largely dependent on the molecular structure of the test environment. Crack growth at high velocities was limited by either transport of the reactive species to the crack tip or by viscous drag contributions. Results are discussed in the context of the current mechanistic models proposed for the stress corrosion of bulk silica. (C) 2007 American Institute of Physics. C1 Univ Calif Berkeley, Dept Mat Sci Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Card, JC (reprint author), Univ Calif Berkeley, Dept Mat Sci Engn, Berkeley, CA 94720 USA. EM roritchie@lbl.gov RI Ritchie, Robert/A-8066-2008 OI Ritchie, Robert/0000-0002-0501-6998 NR 68 TC 7 Z9 7 U1 1 U2 16 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD SEP 1 PY 2007 VL 102 IS 5 AR 053516 DI 10.1063/1.2775998 PG 12 WC Physics, Applied SC Physics GA 210RU UT WOS:000249474100031 ER PT J AU Lee, A Liu, W Ho, CE Subramanian, KN AF Lee, A. Liu, W. Ho, C. E. Subramanian, K. N. TI Synchrotron x-ray microscopy studies on electromigration of a two-phase material SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SOLDER JOINTS; ALUMINUM FILMS; COPPER; LEAD AB Basic issues involving movement of conductive constituents and microstructural evolution from high current density in single phase materials are well documented. Recently, electromigration of conductive constituents in multiphase materials has gained attention due to the necessity of employing such alloys for interconnects in microelectronics. Reported studies on these alloys using complicated industrial geometry suffer from contributions such as current crowding. Hence a basic understanding on operative mechanisms during electromigration in multiphase alloys cannot be gained from these studies. Consequently, several mechanisms proposed from these studies involve fitting parameters and not well-understood complex diffusional processes. A joint configuration designed to avoid current crowding and associated local Joule heating is suitable for evaluating electromigration induced microstructural events. Synchrotron x-ray microscopy has provided information regarding two- and three-dimensional crystallographic orientations and strain fields in such joints, aiding the development of a basic understanding of electromigration in two-phase alloys. (C) 2007 American Institute of Physics. C1 Michigan State Univ, Dept Chem Engn & Mat Sci, E Lansing, MI 48824 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Lee, A (reprint author), Michigan State Univ, Dept Chem Engn & Mat Sci, E Lansing, MI 48824 USA. EM leea@egr.msu.edu NR 18 TC 20 Z9 21 U1 3 U2 15 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD SEP 1 PY 2007 VL 102 IS 5 AR 053507 DI 10.1063/1.2777122 PG 5 WC Physics, Applied SC Physics GA 210RU UT WOS:000249474100022 ER PT J AU Ni, X Ozgur, U Morkoc, H Liliental-Weber, Z Everitt, HO AF Ni, X. Oezguer, U. Morkoc, H. Liliental-Weber, Z. Everitt, H. O. TI Epitaxial lateral overgrowth of a-plane GaN by metalorganic chemical vapor deposition SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MULTIPLE-QUANTUM WELLS; SAPPHIRE; FILMS; REDUCTION; DEFECTS AB We report on epitaxial lateral overgrowth (ELO) of (<11(2)over bar0>) a-plane GaN by metalorganic chemical vapor deposition. Different growth rates of Ga- and N-polar wings together with wing tilt create a major obstacle for achieving a smooth, fully coalesced surface in ELO a-plane GaN. To address this issue a two-step growth method was employed to provide a large aspect ratio of height to width in the first growth step followed by enhanced lateral growth in the second by controlling the growth temperature. By this method, the average ratio of Ga- to N-polar wing growth rate has been reduced from 4-6 to 1.5-2, which consequently reduced the wing-tilt induced height difference between the two approaching wings at the coalescence front, thereby making their coalescence much easier. Transmission electron microscopy showed that the threading dislocation density in the wing regions was 1.0x10(8) cm(-2), more than two orders of magnitude lower than that in the window regions (4.2x10(10) cm(-2)). However, a relatively high density of basal stacking faults of 1.2x10(4) cm(-1) was still present in the wing regions as compared to c -plane GaN, where they are rarely observed away from the substrate. Atomic force microscopy (AFM) measurements showed two orders of magnitude higher density of surface pits in the window than in the wing regions, which were considered to be terminated by dislocations (partial ones related to stacking faults and full ones) on the surface. The existence of basal stacking faults was also revealed by AFM measurements on the a-plane ELO sample after wet chemical etching in hot H3PO4/H2SO4 (1:1). The extensions of Ga-polar wings near the meeting fronts were almost free of stacking faults. The improvement of crystalline quality in the overgrown layer by ELO was also verified by near field scanning optical microscopy and time-resolved photoluminescence measurements; the former showing strongly enhanced luminescence from the wing regions, and the latter indicating longer decay times (0.25 ns) compared to a standard a-plane GaN template (40 ps). (C) 2007 American Institute of Physics. C1 Virginia Commonwealth Univ, Dept Elect Engn, Richmond, VA 23284 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Duke Univ, Dept Phys, Durham, NC 27708 USA. USA Aviat & Missile Res, Ctr Dev & Engn, Redstone Arsenal, AL 35898 USA. RP Ni, X (reprint author), Virginia Commonwealth Univ, Dept Elect Engn, Richmond, VA 23284 USA. EM nix@vcu.edu RI Ni, Xianfeng/A-9429-2008; Ni, Xianfeng/A-1635-2011; Liliental-Weber, Zuzanna/H-8006-2012; Everitt, Henry/L-7118-2013 OI Everitt, Henry/0000-0002-8141-3768 NR 23 TC 26 Z9 27 U1 1 U2 13 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD SEP 1 PY 2007 VL 102 IS 5 AR 053506 DI 10.1063/1.2773692 PG 7 WC Physics, Applied SC Physics GA 210RU UT WOS:000249474100021 ER PT J AU Schmalhorst, J Thomas, A Reiss, G Kou, X Arenholz, E AF Schmalhorst, J. Thomas, A. Reiss, G. Kou, X. Arenholz, E. TI Influence of chemical and magnetic interface properties of Co-Fe-B/MgO/Co-Fe-B tunnel junctions on the annealing temperature dependence of the magnetoresistance SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CIRCULAR-DICHROISM; ROOM-TEMPERATURE AB The knowledge of chemical and magnetic conditions at the Co40Fe40B20/MgO interface is important to interpret the strong annealing temperature dependence of tunnel magnetoresistance of Co-Fe-B/MgO/Co-Fe-B magnetic tunnel junctions, which increases with annealing temperature from 20% after annealing at 200 degrees C up to a maximum value of 112% after annealing at 350 degrees C. While the well defined nearest neighbor ordering indicating crystallinity of the MgO barrier does not change by the annealing, a small amount of interfacial Fe-O at the lower Co-Fe-B/MgO interface is found in the as grown samples, which is completely reduced after annealing at 275 degrees C. This is accompanied by a simultaneous increase of the Fe magnetic moment and the tunnel magnetoresistance. However, the tunneling magnetoresistance of the MgO based junctions increases further for higher annealing temperature which cannot be caused by Fe-O reduction. The occurrence of an x-ray absorption near-edge structure above the Fe and Co L edges after annealing at 350 degrees C indicates the recrystallization of the Co-Fe-B electrode. This is a prerequisite for coherent tunneling and has been suggested to be responsible for the further increase of the tunneling magnetoresistance above 275 degrees C. Simultaneously, the B concentration in the Co-Fe-B decreases with increasing annealing temperature, at least some of the B diffuses toward or into the MgO barrier and forms a B2O3 oxide. (C) 2007 American Institute of Physics. C1 Univ Bielefeld, Dept Phys, D-33501 Bielefeld, Germany. Lanzhou Univ, Lanzhou 730000, Peoples R China. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Schmalhorst, J (reprint author), Univ Bielefeld, Dept Phys, D-33501 Bielefeld, Germany. EM jschmalh@physik.uni-bielefeld.de RI Thomas, Andy/C-7210-2008; Schmalhorst, Jan/E-9951-2011; Reiss, Gunter/A-3423-2010 OI Thomas, Andy/0000-0001-8594-9060; Reiss, Gunter/0000-0002-0918-5940 NR 17 TC 19 Z9 20 U1 1 U2 8 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD SEP 1 PY 2007 VL 102 IS 5 AR 053907 DI 10.1063/1.2776001 PG 4 WC Physics, Applied SC Physics GA 210RU UT WOS:000249474100056 ER PT J AU Sigman, J Clem, PG Nordquist, CD Richardson, JJ Dawley, JT AF Sigman, J. Clem, P. G. Nordquist, C. D. Richardson, J. J. Dawley, J. T. TI Effect of microstructure on the dielectric properties of compositionally graded (Ba,Sr)TiO3 films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CHEMICAL SOLUTION DEPOSITION; MULTILAYERED THIN-FILMS; PULSED-LASER DEPOSITION; SRTIO3; LAYER; (BA0.80SR0.20)(TI1-XZRX)O-3; CRYSTALLIZATION; TUNABILITY AB The demand for better performing radio frequency (RF) and microwave devices has led to research on lower dielectric loss and more temperature-stable dielectric materials. In this work, we report on an approach to decrease the temperature coefficient of capacitance (TCC) of (Ba,Sr)TiO3, which is desirable for improved stability of phase shifter elements, voltage-controlled oscillators, and other tunable devices. We have grown and characterized a series of single-composition and compositionally-graded films with both parallel plate and interdigitated (IDC) electrodes. Graded films with larger Ba2+ concentrations in the initially-grown layers, as well those films crystallized at lower temperatures, displayed the lowest TCC. An asymmetrically graded BaTiO3/Ba0.50Sr0.50TiO3/SrTiO3 film on polycrystalline alumina crystallized at 750 degrees C yielded the lowest observed TCC of -150 ppm/degrees C, a dielectric constant of 240, 20% tuning of permittivity (0-40 V-DC, 80 kV/cm), and losses below 1%, measured at 100 kHz. The microstructures of graded films were examined and found to play an important role in determining not only the TCC of graded films but also film dielectric constants. In particular, it was found that films with BaTiO3-rich compositions displayed overall finer grain structures that appear to suppress the ferroelectric behavior. The effect of electrode configuration on the TCC, dielectric constant, and dielectric losses in compositionally-graded films is also discussed. (C) 2007 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87123 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Nozomi Photon, San Jose, CA 95131 USA. RP Sigman, J (reprint author), Sandia Natl Labs, Albuquerque, NM 87123 USA. EM jsigman@sandia.gov RI Richardson, Jacob/B-7535-2009 OI Richardson, Jacob/0000-0003-2733-9736 NR 29 TC 12 Z9 13 U1 2 U2 16 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD SEP 1 PY 2007 VL 102 IS 5 AR 054106 DI 10.1063/1.2775922 PG 7 WC Physics, Applied SC Physics GA 210RU UT WOS:000249474100067 ER PT J AU Solovyov, VF Wiesmann, HJ Suenaga, M AF Solovyov, Vyacheslav F. Wiesmann, Harold J. Suenaga, Masaki TI Critical current densities and the structural quality of 3-and 4-mu m-thick superconducting YBa2Cu3O7 layers synthesized using the ex situ process SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID POSTDEPOSITION REACTION PROCESS; FILMS; GROWTH; NUCLEATION; CONDUCTORS; DEPOSITION; MECHANISMS; TAPES; YBCO AB In this work, we used quantitative x-ray diffraction measurements and optical metallography to investigate the relationship between structural quality and critical current densities J(c) for 3- and 4-mu m-thick YBa2Cu3O7 (YBCO) films grown on CeO2-buffered Ni-W substrates by the BaF2 process. The J(c) of the films was shown to be approximately: (1) proportional to the intensity of the YBCO (006) diffraction line, and (2) inversely proportional to the average grain size of the c-axis oriented YBCO as determined from optical micrographs of polished surface of the films. We conclude that to achieve J(c)s well above 10(6) A/cm(2) in self-field and at 77 K, it is critical to suppress the formation of randomly oriented YBCO grains while maintaining high crystallographic quality of the c-axis oriented part of the film. The quality of the c-axis oriented YBCO was found to be strongly dependent on the YBCO grains size-e.g., the grains, which are smaller than 10 mu m, are required for high J(c) films. The fine-grain high J(c) films can be synthesized under processing conditions that promote a high rate of nucleation of c-axis oriented YBCO. (C) 2007 American Institute of Physics. C1 Brookhaven Natl Lab, Condensed Matter Phys & Mat Sci Dept, Upton, NY 11973 USA. RP Solovyov, VF (reprint author), Brookhaven Natl Lab, Condensed Matter Phys & Mat Sci Dept, 76 Cornell Ave, Upton, NY 11973 USA. EM solov@bnl.gov RI Solovyov, Vyacheslav/A-7724-2009; OI Solovyov, Vyacheslav/0000-0003-1879-9802 NR 18 TC 4 Z9 4 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD SEP 1 PY 2007 VL 102 IS 5 AR 053902 DI 10.1063/1.2773997 PG 6 WC Physics, Applied SC Physics GA 210RU UT WOS:000249474100051 ER PT J AU Plomp, M McCaffery, JM Cheong, I Huang, X Bettegowda, C Kinzler, KW Zhou, SB Vogelstein, B Malkin, AJ AF Plomp, Marco McCaffery, J. Michael Cheong, Ian Huang, Xin Bettegowda, Chetan Kinzler, Kenneth W. Zhou, Shibin Vogelstein, Bert Malkin, Alexander J. TI Spore coat architecture of Clostridium novyi NT SporeS SO JOURNAL OF BACTERIOLOGY LA English DT Article ID ATOMIC-FORCE MICROSCOPY; X-RAY-MICROANALYSIS; BACILLUS-CEREUS; BACTERIOLYTIC THERAPY; STRUCTURAL DYNAMICS; ELECTRON-MICROSCOPY; EXPERIMENTAL-TUMORS; BACTERIAL-SPORES; SPIRAL GROWTH; SURFACES AB Spores of the anaerobic bacterium Clostridium novyi NT are able to germinate in and destroy hypoxic regions of tumors in experimental animals. Future progress in this area will benefit from a better understanding of the germination and outgrowth processes that are essential for the tumorilytic properties of these spores. Toward this end, we have used both transmission electron microscopy and atomic force microscopy to determine the structure of both dormant and germinating spores. We found that the spores are surrounded by an amorphous layer intertwined with honeycomb parasporal layers. Moreover, the spore coat layers had apparently self-assembled, and this assembly was likely to be governed by crystal growth principles. During germination and outgrowth, the honeycomb layers, as well as the underlying spore coat and undercoat layers, sequentially dissolved until the vegetative cell was released. In addition to their implications for understanding the biology of C. novyi NT, these studies document the presence of proteinaceous growth spirals in a biological organism. C1 Johns Hopkins Univ, Sidney Kimmel Comprehens Canc Ctr, Howard Hughes Med Inst, Baltimore, MD 21231 USA. Johns Hopkins Univ, Sidney Kimmel Comprehens Canc Ctr, Ludwig Ctr Canc Genet & Therapeut, Baltimore, MD 21231 USA. Lawrence Livermore Natl Lab, Dept Chem Mat & Life Sci, Livermore, CA 94551 USA. Johns Hopkins Univ, Dept Biol, Baltimore, MD 21218 USA. RP Vogelstein, B (reprint author), Johns Hopkins Univ, Sidney Kimmel Comprehens Canc Ctr, Howard Hughes Med Inst, 1650 Orleans St,CRB1, Baltimore, MD 21231 USA. EM vogelbe@welch.jhu.edu; malkin1@llnl.gov FU NCI NIH HHS [P50 CA062924, CA 62924]; NCRR NIH HHS [S10 RR019409-01, S10 RR021023-01, S10 RR022588-01, S10 RR023454-01] NR 59 TC 28 Z9 29 U1 2 U2 12 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD SEP PY 2007 VL 189 IS 17 BP 6457 EP 6468 DI 10.1128/JB.00757-07 PG 12 WC Microbiology SC Microbiology GA 204JY UT WOS:000249041100041 PM 17586633 ER PT J AU Haft, RJF Gachelet, EG Nguyen, T Toussaint, L Chivian, D Traxler, B AF Haft, Rembrandt J. F. Gachelet, Eliora G. Nguyen, Tran Toussaint, Luttrell Chivian, Dylan Traxler, Beth TI In vivo oligomerization of the F conjugative coupling protein TraD SO JOURNAL OF BACTERIOLOGY LA English DT Article ID IV SECRETION SYSTEM; BINDING CASSETTE TRANSPORTER; DNA-TRANSFER-SYSTEMS; INCHI1 PLASMID R27; BACTERIAL CONJUGATION; ESCHERICHIA-COLI; FUNCTIONAL DOMAINS; AGROBACTERIUM-TUMEFACIENS; TRANSMEMBRANE DOMAIN; NUCLEOTIDE-BINDING AB Type IV secretory systems are a group of bacterial transporters responsible for the transport of proteins and nucleic acids directly into recipient cells. Such systems play key roles in the virulence of some pathogenic organisms and in conjugation-mediated horizontal gene transfer. Many type IV systems require conserved "coupling proteins," transmembrane polypeptides that are critical for transporting secreted substrates across the cytoplasmic membrane of the bacterium. In vitro evidence suggests that the functional form of coupling proteins is a homohexameric, ring-shaped complex. Using a library of tagged mutants, we investigated the structural and functional organization of the F plasmid conjugative coupling protein TraD by coimmunoprecipitation, cross-linking, and genetic means. We present direct evidence that coupling proteins form stable oligomeric complexes in the membranes of bacteria and that the formation of some of these complexes requires other F-encoded functions. Our data also show that different regions of TraD play distinct roles in the oligomerization process. We postulate a model for in vivo oligomerization and discuss the probable participation of individual domains of TraD in each step. C1 Univ Washington, Dept Microbiol, Seattle, WA 98195 USA. Univ Washington, Dept Biochem, Seattle, WA 98195 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Traxler, B (reprint author), Univ Washington, Dept Microbiol, Box 357242, Seattle, WA 98195 USA. EM btraxler@u.washington.edu FU NHLBI NIH HHS [T35 HL007763, T35 HL07763]; NIGMS NIH HHS [T32 GM007270, T32 GM07270] NR 52 TC 10 Z9 10 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD SEP PY 2007 VL 189 IS 18 BP 6626 EP 6634 DI 10.1128/JB.00513-07 PG 9 WC Microbiology SC Microbiology GA 209JJ UT WOS:000249384500015 PM 17631633 ER PT J AU Hartshorne, RS Jepson, BN Clarke, TA Field, SJ Fredrickson, J Zachara, J Shi, L Butt, JN Richardson, DJ AF Hartshorne, Robert S. Jepson, Brian N. Clarke, Tom A. Field, Sarah J. Fredrickson, Jim Zachara, John Shi, Liang Butt, Julea N. Richardson, David J. TI Characterization of Shewanella oneidensis MtrC: a cell-surface decaheme cytochrome involved in respiratory electron transport to extracellular electron acceptors SO JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY LA English DT Article DE cytochrome c; iron respiration; electron transfer; protein film voltammetry; electron paramagnetic resonance ID OUTER-MEMBRANE CYTOCHROMES; C-TYPE CYTOCHROMES; PUTREFACIENS MR-1; HYDROXYLAMINE OXIDOREDUCTASE; ANAEROBIC RESPIRATION; NITRITE REDUCTASE; FRIGIDIMARINA NCIMB400; REDUCING BACTERIUM; ESCHERICHIA-COLI; ACTIVE-SITE AB MtrC is a decaheme c-type cytochrome associated with the outer cell membrane of Fe(III)-respiring species of the Shewanella genus. It is proposed to play a role in anaerobic respiration by mediating electron transfer to extracellular mineral oxides that can serve as terminal electron acceptors. The present work presents the first spectropotentiometric and voltammetric characterization of MtrC, using protein purified from Shewanella oneidensis MR-1. Potentiometric titrations, monitored by UV-vis absorption and electron paramagnetic resonance (EPR) spectroscopy, reveal that the hemes within MtrC titrate over a broad potential range spanning between approximately +100 and approximately -500 mV (vs. the standard hydrogen electrode). Across this potential window the UV-vis absorption spectra are characteristic of low-spin c-type hemes and the EPR spectra reveal broad, complex features that suggest the presence of magnetically spin-coupled low-spin c-hemes. Non-catalytic protein film voltammetry of MtrC demonstrates reversible electrochemistry over a potential window similar to that disclosed spectroscopically. The voltammetry also allows definition of kinetic properties of MtrC in direct electron exchange with a solid electrode surface and during reduction of a model Fe(III) substrate. Taken together, the data provide quantitative information on the potential domain in which MtrC can operate. C1 Univ E Anglia, Sch Biol Sci, Ctr Metalloprot Spect & Biol, Norwich NR4 7TJ, Norfolk, England. Univ E Anglia, Sch Chem Sci & Pharm, Norwich NR4 7TJ, Norfolk, England. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Butt, JN (reprint author), Univ E Anglia, Sch Biol Sci, Ctr Metalloprot Spect & Biol, Norwich NR4 7TJ, Norfolk, England. EM j.butt@uea.ac.uk; richardson@uea.ac.uk RI Richardson, David/E-2275-2011; clarke, tom/D-1837-2009; Butt, Julea/E-2133-2011 OI clarke, tom/0000-0002-6234-1914; Butt, Julea/0000-0002-9624-5226 FU Biotechnology and Biological Sciences Research Council [B18695] NR 45 TC 106 Z9 107 U1 7 U2 49 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0949-8257 J9 J BIOL INORG CHEM JI J. Biol. Inorg. Chem. PD SEP PY 2007 VL 12 IS 7 BP 1083 EP 1094 DI 10.1007/s00775-007-0278-y PG 12 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 206WO UT WOS:000249213800013 PM 17701062 ER PT J AU Gourley, PL Hendricks, JK McDonald, AE Copeland, RG Yaffe, MP Naviaux, RK AF Gourley, Paul L. Hendricks, Judy K. McDonald, Anthony E. Copeland, R. Guild Yaffe, Michael P. Naviaux, Robert K. TI Reactive biomolecular divergence in genetically altered yeast cells and isolated mitochondria as measured by biocavity laser spectroscopy: rapid diagnostic method for studying cellular responses to stress and disease SO JOURNAL OF BIOMEDICAL OPTICS LA English DT Article DE Saccharomyces cerevisiae; yeast; mitochondria; biocavity laser; spectroscopy; microscopy; optics; refractive index ID CYTOCHROME-C-OXIDASE; BIOLOGY; ACID AB We report an analysis of four strains of baker's yeast (Saccharomyces cerevisiae) using biocavity laser spectroscopy. The four strains are grouped in two pairs (wild type and altered), in which one strain differs genetically at a single locus, affecting mitochondrial function. In one pair, the wild-type rho(+) and a rho(0) strain differ by complete removal of mitochondrial DNA (mtDNA ). In the second pair, the wild-type rho(+) and a rho(-) strain differ by knock-out of the nuclear gene encoding Cox4, an essential subunit of cytochrome c oxidase. The biocavity laser is used to measure the biophysical optic parameter Delta lambda, a laser wavelength shift relating to the optical density of cell or mitochondria that uniquely reflects its size and biomolecular composition. As such, Delta lambda is a powerful parameter that rapidly interrogates the biomolecular state of single cells and mitochondria. Wild-type cells and mitochondria produce Gaussian-like distributions with a single peak. In contrast, mutant cells and mitochondria produce leptokurtotic distributions that are asymmetric and highly skewed to the right. These distribution changes could be self-consistently modeled with a single, log-normal distribution undergoing a thousand-fold increase in variance of biomolecular composition. These features reflect a new state of stressed or diseased cells that we call a reactive biomolecular divergence (RBD) that reflects the vital interdependence of mitochondria and the nucleus. (C) 2007 Society of Photo-Optical Instrumentation Engineers. C1 [Gourley, Paul L.; Hendricks, Judy K.; McDonald, Anthony E.; Copeland, R. Guild] Sandia Natl Labs, Dept 8331, Albuquerque, NM 87185 USA. [Yaffe, Michael P.] Univ Calif San Diego, Div Biol Sci, La Jolla, CA 92093 USA. [Naviaux, Robert K.] Univ Calif San Diego, Mitochondrial & Metab Dis Ctr, San Diego, CA 92103 USA. RP Gourley, PL (reprint author), Sandia Natl Labs, MS 1413, 8331, Albuquerque, NM 87122 USA. EM plgourl@sandia.gov; naviaux@ucsd.edu FU NIGMS NIH HHS [GM44614] NR 28 TC 2 Z9 2 U1 0 U2 1 PU SPIE-SOC PHOTOPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 1083-3668 J9 J BIOMED OPT JI J. Biomed. Opt. PD SEP-OCT PY 2007 VL 12 IS 5 AR 054003 DI 10.1117/1.2799198 PG 14 WC Biochemical Research Methods; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Biochemistry & Molecular Biology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA 239WS UT WOS:000251549600034 PM 17994891 ER PT J AU Pan, YT Wu, ZL Yuan, ZJ Wang, ZG Du, CW AF Pan, Ying T. Wu, Zi L. Yuan, Zhi J. Wang, Zheng G. Du, Cong W. TI Subcellular imaging of epithelium with time-lapse optical coherence tomography SO JOURNAL OF BIOMEDICAL OPTICS LA English DT Article DE tomography; optics; coherence; biomedical optics; subcellular; cancer ID MICROSCOPY AB We present the first experimental result of direct delineation of the nuclei of living rat bladder epithelium with ultrahigh-resolution optical coherence tomography (uOCT). We demonstrate that the cellular details embedded in the speckle noise in a uOCT image can be uncovered by time-lapse frame averaging that takes advantage of the micromotion in living biological tissue. The uOCT measurement of the nuclear size (7.9 +/- 1.4 mu m) closely matches the histological evaluation (7.2 +/- 0.8 mu m) . Unlike optical coherence microscopy (OCM), which requires a sophisticated high-NA microscopic objective, this approach uses a commercial-grade single achromatic lens (f/10mm,NA/0.25) and provides a cross-sectional image over 0.6 mm of depth without focus tracking, thus holding great promise of endoscopic optical biopsy for diagnosis and grading of flat epithelial cancer such as carcinoma in situ in vivo. (c) 2007 Society of Photo-Optical Instrumentation Engineers. C1 [Pan, Ying T.; Wu, Zi L.; Yuan, Zhi J.; Wang, Zheng G.] SUNY Stony Brook, Dept Biomed Engn, Stony Brook, NY 11794 USA. [Du, Cong W.] SUNY Stony Brook, Dept Anesthesiol, Upton, NY 11973 USA. [Du, Cong W.] Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Pan, YT (reprint author), SUNY Stony Brook, Dept Biomed Engn, Stony Brook, NY 11794 USA. EM yingtian.pan@sunysb.edu RI yuan, zhijia/F-4314-2011 FU NIDDK NIH HHS [2R01-DK059265, R01-DK068401] NR 6 TC 15 Z9 15 U1 0 U2 1 PU SPIE-SOC PHOTOPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 1083-3668 J9 J BIOMED OPT JI J. Biomed. Opt. PD SEP-OCT PY 2007 VL 12 IS 5 AR 050504 DI 10.1117/1.2800007 PG 3 WC Biochemical Research Methods; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Biochemistry & Molecular Biology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA 239WS UT WOS:000251549600003 PM 17994860 ER PT J AU Vogel, A Chernomordik, VV Riley, JD Hassan, M Amyot, F Dasgeb, B Demos, SG Pursley, R Little, RF Yarchoan, R Tao, Y Gandjbakhche, AH AF Vogel, Abby Chernomordik, Victor V. Riley, Jason D. Hassan, Moinuddin Amyot, Franck Dasgeb, Bahar Demos, Stavros G. Pursley, Randall Little, Richard F. Yarchoan, Robert Tao, Yang Gandjbakhche, Amir H. TI Using noninvasive multispectral imaging to quantitatively assess tissue vasculature SO JOURNAL OF BIOMEDICAL OPTICS LA English DT Article; Proceedings Paper CT Conference on Water Environment-Membrane Technology CY JUN 07-10, 2004 CL Seoul, SOUTH KOREA SP IWA DE multispectral imaging; tissue oxygenation; blood volume; drug therapy monitoring; quantitative assessment; functional information ID NEAR-INFRARED SPECTROSCOPY; ENDOTHELIAL GROWTH-FACTOR; KAPOSIS-SARCOMA; PARAMETERS; THERAPY; LIGHT; SKIN; ANGIOGENESIS; HEMOGLOBIN AB This research describes a noninvasive, noncontact method used to quantitatively analyze the functional characteristics of tissue. Multispectral images collected at several near-infrared wavelengths are input into a mathematical optical skin model that considers the contributions from different analytes in the epidermis and dermis skin layers. Through a reconstruction algorithm, we can quantify the percent of blood in a given area of tissue and the fraction of that blood that is oxygenated. Imaging normal tissue confirms previously reported values for the percent of blood in tissue and the percent of blood that is oxygenated in tissue and surrounding vasculature, for the normal state and when ischemia is induced. This methodology has been applied to assess vascular Kaposi's sarcoma lesions and the surrounding tissue before and during experimental therapies. The multispectral imaging technique has been combined with laser Doppler imaging to gain additional information. Results indicate that these techniques are able to provide quantitative and functional information about tissue changes during experimental drug therapy and investigate progression of disease before changes are visibly apparent, suggesting a potential for them to be used as complementary imaging techniques to clinical assessment. (c) 2007 Society of Photo-Optical Instrumentation Engineers. C1 [Vogel, Abby; Chernomordik, Victor V.; Riley, Jason D.; Hassan, Moinuddin; Amyot, Franck; Dasgeb, Bahar; Gandjbakhche, Amir H.] NICHHD, NIH, Lab Integrat & Med Biophys, Bethesda, MD 20892 USA. [Vogel, Abby; Tao, Yang] Univ Maryland, Fischell Dept Bioengn, Bioimaging & Machine Vis Lab, College Pk, MD 20742 USA. [Demos, Stavros G.] Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. [Pursley, Randall] NIH, Ctr Informat Technol, Bethesda, MD 20892 USA. [Little, Richard F.; Yarchoan, Robert] NCI, NIH, HIV & AIDS Malignancy Branch, Bethesda, MD 20892 USA. RP Gandjbakhche, AH (reprint author), NICHHD, NIH, Lab Integrat & Med Biophys, 9000 Rockville Pike,Bldg 9,Room B1E11, Bethesda, MD 20892 USA. EM amir@helix.nih.gov FU Intramural NIH HHS [Z01 CT000261-11] NR 30 TC 46 Z9 46 U1 0 U2 3 PU SPIE-SOC PHOTOPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 1083-3668 J9 J BIOMED OPT JI J. Biomed. Opt. PD SEP-OCT PY 2007 VL 12 IS 5 AR 051604 DI 10.1117/1.2801718 PG 13 WC Biochemical Research Methods; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Biochemistry & Molecular Biology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA 239WS UT WOS:000251549600016 PM 17994873 ER PT J AU Bandstra, ER Judex, S Vazquez, ME Bateman, TA AF Bandstra, E. R. Judex, S. Vazquez, M. E. Bateman, T. A. TI Murine bone loss following local irradiation SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Bandstra, E. R.; Bateman, T. A.] Clemson Univ, Clemson, SC 29631 USA. [Judex, S.] SUNY Stony Brook, Stony Brook, NY 11794 USA. [Vazquez, M. E.] Brookhaven Natl Lab, Dept Med, Upton, NY USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 MA M145 BP S161 EP S161 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509100601 ER PT J AU Cheng, Z Yao, W Koester, KJ Balooch, M Ritchie, RO Lane, NE AF Cheng, Z. Yao, W. Koester, K. J. Balooch, M. Ritchie, R. O. Lane, N. E. TI PTH improves bone strength in an osteoporosis model through increasing mineralized matrix yet the elastic modulus of the trabecular surface is more heterogeneous than observed with anti-resorptive agents SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Cheng, Z.; Yao, W.; Lane, N. E.] Univ Calif Davis, Med Ctr, Ctr Healthy Aging, Sacramento, CA 95817 USA. [Koester, K. J.; Balooch, M.; Ritchie, R. O.] Lawrence Berkeley Lab, Mat Sci Div, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 MA S392 BP S124 EP S124 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509100457 ER PT J AU Collette, NM Harland, RM Loots, GG AF Collette, N. M. Harland, R. M. Loots, G. G. TI Selerostin overexpression impairs limb patterning SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Collette, N. M.; Loots, G. G.] Lawrence Livermore Natl Lab, Biosci & Biotechnol Div, Livermore, CA USA. [Harland, R. M.] Univ Calif Berkeley, Dept Mol & Cellular Biol, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 BP S104 EP S104 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509100382 ER PT J AU Collette, NM Harland, RM Loots, GG AF Collette, N. M. Harland, R. M. Loots, G. G. TI Sclerostin overexpression impairs limb patterning SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Collette, N. M.; Loots, G. G.] Lawrence Livermore Natl Lab, Biosci & Biotechnol Div, Livermore, CA USA. [Harland, R. M.] Univ Calif Berkeley, Dept Mol & Cellular Biol, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 MA O179 BP S85 EP S85 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509100309 ER PT J AU Fitzgerald, RL Burton, DW Griffin, T Deftos, LJ Herold, A Hillegonds, DJ AF Fitzgerald, R. L. Burton, D. W. Griffin, T. Deftos, L. J. Herold, A. Hillegonds, D. J. TI Urinary excretion of Ca-41 in mice: Application of Ca-41 in cancer-induced bone disease SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Fitzgerald, R. L.; Burton, D. W.; Griffin, T.; Deftos, L. J.; Herold, A.] Univ Calif San Diego, VA Med Ctr, San Diego, CA 92103 USA. [Hillegonds, D. J.] Lawrence Livermore Natl Lab, AMS, Livermore, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 MA T236 BP S289 EP S289 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509101457 ER PT J AU Hillegonds, DJ Burton, DW Vogel, JS Denk, E Walczyk, TR Yang, M Vijayakumar, S Herold, DA Deftos, LJ Fitzgerald, RL AF Hillegonds, D. J. Burton, D. W. Vogel, J. S. Denk, E. Walczyk, T. R. Yang, M. Vijayakumar, S. Herold, D. A. Deftos, L. J. Fitzgerald, R. L. TI A new urine assay for sensitive detection and assessment of cancer-induced skeletal perturbations SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Hillegonds, D. J.; Vogel, J. S.] Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. [Burton, D. W.; Herold, D. A.; Deftos, L. J.; Fitzgerald, R. L.] Univ Calif San Diego, San Diego, CA 92103 USA. [Walczyk, T. R.] ETH, Human Nutr Lab, Zurich, Switzerland. [Yang, M.] Anticanc Inc, San Diego, CA USA. [Vijayakumar, S.] Univ Calif Davis, Davis Canc Ctr, Sacramento, CA 95817 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 MA W193 BP S410 EP S410 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509102280 ER PT J AU Karagiosis, SA Karin, NJ AF Karagiosis, S. A. Karin, N. J. TI Lysophosphatidic acid induces osteocyte dendrite outgrowth SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Karagiosis, S. A.; Karin, N. J.] Pacific NW Natl Lab, Div Biol Sci, Richland, WA 99352 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 BP S104 EP S104 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509100383 ER PT J AU Karagiosis, SA Opresko, LK Christer, WB Karin, NJ AF Karagiosis, S. A. Opresko, L. K. Christer, W. B. Karin, N. J. TI Molecular mechanisms of lysophosphatidic acid-stimulated osteoblastic cell chemotaxis SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Karagiosis, S. A.; Opresko, L. K.; Christer, W. B.; Karin, N. J.] Div Biol Sci, Pacific NW Natl Lab, Richland, WA USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 BP S95 EP S95 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509100346 ER PT J AU Koester, KJ Ager, JW Ritchie, RO AF Koester, K. J. Ager, J. W. Ritchie, R. O. TI Evolution of the crack-growth resistance and toughening mechanisms of human cortical bone via in-situ electron microscopy SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Koester, K. J.; Ritchie, R. O.] Univ Calif Berkeley, Berkeley, CA 94720 USA. [Ager, J. W.] Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 MA W455 BP S477 EP S477 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509102541 ER PT J AU Miller, LM Feldman, TC Schirmer, A Smith, RJ Judex, S AF Miller, L. M. Feldman, T. C. Schirmer, A. Smith, R. J. Judex, S. TI Microscopic imaging of bone composition En block with synchrotron infrared microspectroscopy SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Miller, L. M.; Smith, R. J.] Brookhaven Natl Lab, Natl Synchrotron Light, Upton, NY 11973 USA. [Feldman, T. C.] SUNY Stony Brook, Stony Brook, NY USA. [Schirmer, A.; Judex, S.] SUNY Stony Brook, Stony Brook, NY USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 BP S258 EP S258 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509101333 ER PT J AU Ruppel, ME Carlson, CS Miller, LM AF Ruppel, M. E. Carlson, C. S. Miller, L. M. TI Alterations in collagen structure and mineral composition in calcified cartilage and subchondral bone in a monkey model of OA SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Ruppel, M. E.] SUNY Stony Brook, Stony Brook, NY 11794 USA. [Carlson, C. S.] Univ Minnesota, Coll Vet Med, Dept Vet Populat Med, St Paul, MN 55108 USA. [Miller, L. M.] Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 MA W089 BP S384 EP S384 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509102176 ER PT J AU Schirmer, A Ferreri, S Miller, LM Qin, Y Turner, N Lupton, J Judex, S AF Schirmer, A. Ferreri, S. Miller, L. M. Qin, Y. Turner, N. Lupton, J. Judex, S. TI Interrelation between dietary fatty acids and fibers in modulating bone quantity and quality during skeletal growth SO JOURNAL OF BONE AND MINERAL RESEARCH LA English DT Meeting Abstract CT 29th Annual Meeting of the American-Society-for-Bone-and-Mineral-Research CY SEP 16-19, 2007 CL Honolulu, HI SP Amer Soc Bone & Mineral Res C1 [Schirmer, A.; Ferreri, S.; Qin, Y.; Judex, S.] SUNY Stony Brook, Stony Brook, NY 11794 USA. [Miller, L. M.] Brookhaven Natl Lab, Upton, NY 11973 USA. [Turner, N.; Lupton, J.] Texas A&M Univ, College Stn, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC BONE & MINERAL RES PI WASHINGTON PA 2025 M ST, N W, STE 800, WASHINGTON, DC 20036-3309 USA SN 0884-0431 J9 J BONE MINER RES JI J. Bone Miner. Res. PD SEP PY 2007 VL 22 SU 1 MA W467 BP S481 EP S481 PG 1 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 225IA UT WOS:000250509102553 ER PT J AU Innis, RB Cunningham, VJ Delforge, J Fujita, M Giedde, A Gunn, RN Holden, J Houle, S Huang, SC Ichise, M Lida, H Ito, H Kimura, Y Koeppe, RA Knudsen, GM Knuuti, J Lammertsma, AA Laruelle, M Logan, J Maguire, RP Mintun, MA Morris, ED Parsey, R Price, JC Slifstein, M Sossi, V Suhara, T Votaw, JR Wong, DF Carson, RE AF Innis, Robert B. Cunningham, Vincent J. Delforge, Jacques Fujita, Masahiro Giedde, Albert Gunn, Roger N. Holden, James Houle, Sylvain Huang, Sung-Cheng Ichise, Masanori Lida, Hidehiro Ito, Hiroshi Kimura, Yuichi Koeppe, Robert A. Knudsen, Gitte M. Knuuti, Juhani Lammertsma, Adriaan A. Laruelle, Marc Logan, Jean Maguire, Ralph Paul Mintun, Mark A. Morris'o, Evan D. Parsey, Ramin Price, Julie C. Slifstein, Mark Sossi, Vesna Suhara, Tetsuya Votaw, John R. Wong, Dean F. Carson, Richard E. TI Consensus nomenclature for in vivo imaging of reversibly binding radioligands SO JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM LA English DT Review DE PET; SPECT; modeling; nomenclature; molecular imaging; radioligands ID POSITRON EMISSION TOMOGRAPHY; CONSTANT INFUSION; MODEL; RECEPTOR; INVIVO; VOLUME AB An international group of experts in pharmacokinetic modeling recommends a nomenclature to describe in vivo molecular imaging of reversibly binding radioligands. C1 NIMH, Mol Imaging Branch, Bethesda, MD 20892 USA. Univ London Imperial Coll Sci Technol & Med, London, England. GlaxoSmithKline Inc, London, England. CEA, DSV, SHF, Orsay, France. Univ Aarhus, Aarhus, Denmark. Univ Oxford, London, England. Univ Wisconsin, Madison, WI USA. Univ Toronto, Toronto, ON, Canada. Ctr Addict & Mental Hlth, Toronto, ON, Canada. Univ Calif Los Angeles, Sch Med, Los Angeles, CA USA. Columbia Univ, New York, NY USA. Natl Cardiovasc Ctr, Res Inst, Suita, Osaka 565, Japan. Tokyo Metropolitan Inst Gerontol, Tokyo, Japan. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Copenhagen Hosp, Rigshosp, DK-2100 Copenhagen, Denmark. Turku PET Ctr, Turku, Finland. Vrije Univ Amsterdam Med Ctr, Amsterdam, Netherlands. Brookhaven Natl Lab, Upton, NY 11973 USA. Pfizer Global R&D, Groton, CT USA. Washington Univ, Sch Med, St Louis, MO USA. Indiana Univ Purdue Univ, Indianapolis, IN 46202 USA. Univ Pittsburgh, Pittsburgh, PA USA. Univ British Columbia, Vancouver, BC V5Z 1M9, Canada. Emory Univ, Atlanta, GA 30322 USA. Johns Hopkins Univ, Sch Med, Baltimore, MD USA. Yale Univ, New Haven, CT USA. Natl Inst Radiol Sci, Chiba 260, Japan. RP Innis, RB (reprint author), NIMH, Mol Imaging Branch, 31 Ctr Dr MSC 2035,Bldg 31,Room B2B37, Bethesda, MD 20892 USA. EM robert.innis@iiih.gov RI Bonefeld, Birgit/B-7936-2010; Kimura, Yuichi/B-3045-2008; Carson, Richard/H-3250-2011; Gunn, Roger/H-1666-2012; Iida, Hidehiro/D-4582-2011; Knudsen, Gitte/C-1368-2013 OI Carson, Richard/0000-0002-9338-7966; Gunn, Roger/0000-0003-1181-5769; Knudsen, Gitte/0000-0003-1508-6866 NR 12 TC 984 Z9 987 U1 7 U2 54 PU NATURE PUBLISHING GROUP PI NEW YORK PA 75 VARICK STREET, 9TH FLOOR, NEW YORK, NY 10013-1917 USA SN 0271-678X J9 J CEREBR BLOOD F MET JI J. Cereb. Blood Flow Metab. PD SEP PY 2007 VL 27 IS 9 BP 1533 EP 1539 DI 10.1038/sj.jcbfm.9600493 PG 7 WC Endocrinology & Metabolism; Hematology; Neurosciences SC Endocrinology & Metabolism; Hematology; Neurosciences & Neurology GA 202ZY UT WOS:000248946100001 PM 17519979 ER PT J AU Kassaee, MH Keffer, DJ Steele, WV AF Kassaee, Mohamad H. Keffer, David J. Steele, William V. TI Theoretical calculation of thermodynamic properties of naphthalene, methylnaphthalenes, and dimethylnaphthalenes SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID INTERNAL ROTATIONS; ENTROPIES AB For this work we performed quantum mechanical (QM) and statistical mechanical (SM) calculations to generate the entropy of 13 aromatic compounds-naphthalene, 2 methylnaphthalene isomers, and 10 dimethyinaphthalene isomers-in the ideal gas state. Density functional theory (DFT) was used to calculate the equilibrium structure and perform a full normal-mode analysis. The DFT level of theory used in this paper is B3LYP/6-31G(d,p). DFT has also been used to determine barriers for the internal rotation contribution to the entropy. For four compounds for which experimental data are available, the calculated entropies have been compared to the experimental values. The calculated entropies match experiment very well, with the percentage errors close to the experimental uncertainty, less than 0.4 %. The equilibrium distribution of dimethylnaphthalene isomers in the mixture is predicted using the calculated entropies and energies from QM and SM calculations in the 300 K to 740 K temperature range. C1 Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Nucl Sci & Technol Div, Oak Ridge, TN 37831 USA. RP Keffer, DJ (reprint author), Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. EM dkeffer@utk.edu RI Keffer, David/C-5133-2014 OI Keffer, David/0000-0002-6246-0286 NR 20 TC 5 Z9 5 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD SEP-OCT PY 2007 VL 52 IS 5 BP 1843 EP 1850 DI 10.1021/je700196j PG 8 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 211CH UT WOS:000249501400054 ER PT J AU Bonfils, C Duffy, PB Lobell, DB AF Bonfils, Celine Duffy, Philip B. Lobell, David B. TI Comments on "methodology and results of calculating central california surface temperature trends: Evidence of human-induced climate change?" SO JOURNAL OF CLIMATE LA English DT Editorial Material ID UNITED-STATES C1 Univ Calif Merced, Sch Nat Sci, Merced, CA USA. Lawrence Livermore Natl Lab, Energy & Environm Directorate, Livermore, CA USA. RP Bonfils, C (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. EM bonfils2@llnl.gov RI Bonfils, Celine/H-2356-2012 OI Bonfils, Celine/0000-0002-4674-5708 NR 10 TC 4 Z9 4 U1 2 U2 10 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD SEP 1 PY 2007 VL 20 IS 17 BP 4486 EP 4489 DI 10.1175/JCLI4247.1 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 207FT UT WOS:000249237700011 ER PT J AU Liu, X Penner, JE Ghan, SJ Wang, M AF Liu, Xiaohong Penner, Joyce E. Ghan, Steven J. Wang, Minghuai TI Inclusion of ice microphysics in the NCAR community atmospheric model version 3 (CAM3) SO JOURNAL OF CLIMATE LA English DT Review ID CIRRUS CLOUD FORMATION; GENERAL-CIRCULATION MODEL; LOWER TROPICAL STRATOSPHERE; CRYSTAL NUMBER DENSITIES; PHASE STRATIFORM CLOUDS; MINERAL DUST; EFFECTIVE RADIUS; (NH4)(2)SO4-H2O PARTICLES; CONTACT NUCLEATION; UPPER TROPOSPHERE AB A prognostic equation for ice crystal number concentration together with an ice nucleation scheme are implemented in the National Center for Atmospheric Research (NCAR) Community Atmospheric Model version 3 (CAM3) with the aim of studying the indirect effect of aerosols on cold clouds. The effective radius of ice crystals, which is used in the radiation and gravitational settlement calculations, is now calculated from model-predicted mass and number of ice crystals rather than diagnosed as a function of temperature. A water vapor deposition scheme is added to replace the condensation and evaporation (C-E) in the standard CAM3 for ice clouds. The repartitioning of total water into liquid and ice in mixed-phase clouds as a function of temperature is removed, and ice supersaturation is allowed. The predicted ice water content in the modified CAM3 is in better agreement with the Aura Microwave Limb Sounder (MLS) data than that in the standard CAM3. The cirrus cloud fraction near the tropical tropopause, which is underestimated in the standard CAM3 as revealed through comparison with the Stratospheric Aerosol and Gas Experiment II (SAGE II) data, is increased by 20%-30%, and the cold temperature bias there is reduced by 1-2 K. However, an increase in the cloud fraction in polar regions makes the underestimation ( by similar to 20 W m(-2)) of downwelling shortwave radiation in the standard CAM3 even worse. A sensitivity test reducing the threshold relative humidity with respect to ice (RHi) for heterogeneous ice nucleation from 120% to 105% (representing nearly perfect ice nuclei) increases the global cloud cover by 1.4%, temperature near the tropical tropopause by 4-5 K, and water vapor in the stratosphere by 50%-80%. C1 Pacific NW Natl Lab, Atmospher Sci & Global Change Div, Richland, WA 99352 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Liu, X (reprint author), Pacific NW Natl Lab, Atmospher Sci & Global Change Div, 3200 Q Ave, Richland, WA 99352 USA. EM Xiaohong.Liu@pnl.gov RI Wang, Minghuai/E-5390-2011; Penner, Joyce/J-1719-2012; Liu, Xiaohong/E-9304-2011; Ghan, Steven/H-4301-2011 OI Wang, Minghuai/0000-0002-9179-228X; Liu, Xiaohong/0000-0002-3994-5955; Ghan, Steven/0000-0001-8355-8699 NR 103 TC 93 Z9 94 U1 1 U2 8 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 EI 1520-0442 J9 J CLIMATE JI J. Clim. PD SEP PY 2007 VL 20 IS 18 BP 4526 EP 4547 DI 10.1175/JCLI4264.1 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 216NU UT WOS:000249885700002 ER PT J AU Steidl, U Steidl, C Ebralidze, A Chapuy, B Han, HJ Will, B Rosenbauer, F Becker, A Wagner, K Koschmieder, S Kobayashi, S Costa, DB Schuiz, T O'Brien, KB Verhaak, RGW Dawel, R Haase, D Trumper, L Krauter, J Kohwi-ShigematSU, T Griesinger, F Tenen, DG AF Steidl, Ulrich Steidl, Christian Ebralidze, Alexander Chapuy, Bjoen Han, Hye-Jung Will, Britta Rosenbauer, Frank Becker, Annegret Wagner, Katharina Koschmieder, Steffen Kobayashi, Susumu Costa, Daniel B. Schuiz, Thomas O'Brien, Karen B. Verhaak, Roel G. W. Dawel, Ruud Haase, Detlef Truemper, Lorenz Krauter, Juergen Kohwi-ShigematSU, Terumi Griesinger, Frank Tenen, Daniel G. TI A distal single nucleotide polymorphism alters long-range reguiavon of the PU-1 gene in acute myeloid leukemia SO JOURNAL OF CLINICAL INVESTIGATION LA English DT Article ID TRANSCRIPTION FACTOR PU.1; HEMATOPOIETIC STEM-CELLS; BINDING PROTEIN; EXPRESSION; SATB1; PROGENITORS; DIFFERENTIATION; CANCER; PROMOTER; ASTHMA AB Targeted disruption of a highly conserved distal enhancer reduces expression of the PU.1 transcription factor by 80% and leads to acute myeloid leukemia (AML) with frequent cytogenetic aberrations in mice. Here we identify a SNP within this element in humans that is more frequent in AML with a complex karyotype, leads to decreased enhancer activity, and reduces PU.1 expression in myeloid progenitors in a development-dependent manner. This SNP inhibits binding of the chromatin-remodeling transcriptional regulator special AT-rich sequence binding protein 1 (SATB1). Overexpression of SATB1 increased PU.1 expression, and siRNA inhibition of SATB1 downregulated PU.1 expression. Targeted disruption of the distal enhancer led to a loss of regulation of PU.1 by SATB1. Interestingly, disruption of SATB1 in mice led to a selective decrease of PU.1 RNA in specific progenitor types (granulocyte-macrophage and megakaryocyte-erythrocyte progenitors) and a similar effect was observed in AML samples harboring this SNP. Thus we have identified a SNP within a distal enhancer that is associated with a subtype of leukemia and exerts a deleterious effect through remote transcriptional dysregulation in specific progenitor subtypes. C1 Harvard Med Sch, Harvard Stem Cell Inst, Harvard Inst Med, Boston, MA USA. Univ Gottingen, Dept Hematol & Oncol, D-3400 Gottingen, Germany. British Columbia Canc Agcy, Dept Pathol, Vancouver, BC V5Z 4E6, Canada. Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA USA. Univ Freiburg, Dept Cell Biol, D-7800 Freiburg, Germany. Max Delbruck Ctr Mol Med, Berlin, Germany. Hannover Med Sch, Dept Hematol Hemostasis & Oncol, D-3000 Hannover, Germany. Univ Hosp, Dept Med Hematol & Oncol, Munster, Germany. Erasmus Univ, Med Ctr, Dept Hematol, Rotterdam, Netherlands. RP Tenen, DG (reprint author), Harvard Inst Med, HIM Bldg,Room 954,77 Ave Louis Pasteur, Boston, MA 02115 USA. EM dtenen@bidmc.harvard.edu FU NCI NIH HHS [CA41456, R01 CA041456] NR 51 TC 73 Z9 77 U1 0 U2 4 PU AMER SOC CLINICAL INVESTIGATION INC PI ANN ARBOR PA 35 RESEARCH DR, STE 300, ANN ARBOR, MI 48103 USA SN 0021-9738 J9 J CLIN INVEST JI J. Clin. Invest. PD SEP PY 2007 VL 117 IS 9 BP 2611 EP 2620 DI 10.1172/JCI30525 PG 10 WC Medicine, Research & Experimental SC Research & Experimental Medicine GA 209JK UT WOS:000249384600032 PM 17694175 ER PT J AU Cortis, A Ghezzehei, TA AF Cortis, Andrea Ghezzehei, Teamrat A. TI On the transport of emulsions in porous media SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE emulsion; porous media; colloidal transport; memory effects ID STABLE EMULSIONS; FILTRATION; MICROEMULSIONS; FLOW; COLUMNS; DILUTE; SANDS; WATER; MODEL AB Emulsions appear in many subsurface applications including bioremediation, surfactant-enhanced remediation, and enhanced oil-recovery. Modeling emulsion transport in porous media is particularly challenging because the theological and physical properties of emulsions are different from averages of the components. Current modeling approaches are based on filtration theories, which are not suited to adequately address the pore-scale permeability fluctuations and reduction of absolute permeability that are often encountered during emulsion transport. In this communication, we introduce a continuous time random walk based alternative approach that captures these unique features of emulsion transport. Calculations based on the proposed approach resulted in excellent match with experimental observations of emulsion breakthrough from the literature. Specifically, the new approach explains the slow late-time tailing behavior that could not be fitted using the standard approach. The theory presented in this paper also provides an important stepping stone toward a generalized self-consistent modeling of multiphase flow. Published by Elsevier Inc. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Cortis, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, 1 Cyclotron Rd,MS 90R1116, Berkeley, CA 94720 USA. EM acortis@lbl.gov RI Cortis, Andrea/A-3525-2008; Ghezzehei, Teamrat/G-7483-2011 OI Ghezzehei, Teamrat/0000-0002-0287-6212 NR 21 TC 14 Z9 14 U1 1 U2 11 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD SEP 1 PY 2007 VL 313 IS 1 BP 1 EP 4 DI 10.1016/j.jcis.2007.04.021 PG 4 WC Chemistry, Physical SC Chemistry GA 194NU UT WOS:000248351900001 PM 17493630 ER PT J AU Gilbert, B Lu, GP Kim, CS AF Gilbert, Benjamin Lu, Guoping Kim, Christopher S. TI Stable cluster formation in aqueous suspensions of iron oxyhydroxide nanoparticles SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE nanoparticles; clusters; aggregation; colloid transport; small-angle X-ray scattering; dynamic light scattering; photon correlation spectroscopy ID ANGLE NEUTRON-SCATTERING; POROUS-MEDIA; COLLOIDAL SUSPENSIONS; CONTAMINANT TRANSPORT; CRYSTAL-GROWTH; PARTICLES; AGGREGATION; SYSTEMS; PLUTONIUM; MIGRATION AB Metal oxide and oxyhydroxide nanoparticles are important components of natural aqueous systems and have application in photocatalysis. Uncoated (oxyhydr)oxide nanoparticles can form charge-stabilized colloids in water, but the precise regimes of dispersion and aggregation have been determined for very few nanomaterials. We studied the colloidal behavior of similar to 6 nm nanoparticles of iron oxyhydroxide (FeOOH), a common natural nanoscale colloid, and found that these nanoparticles formed stable suspended clusters under a range of aqueous conditions. Light and X-ray scattering methods show that suspended fractal nanoclusters are formed between pH 5 and 6.6 with well-defined maximum diameters that can be varied from 25 nm to approximately 1000 nm. The nanoclusters retain a very high surface area, and persist in suspension for at least 10 weeks in solution. The process is partially reversible because optically transparent suspensions are regained when nanoparticles that aggregated and settled at pH > 7 are adjusted to pH 4 without stirring. However, completely redispersed nanoparticles are not obtained even after one month. Because nanocluster formation is controlled predominantly by surface charge, we anticipate that many metal oxide and other inorganic nanoparticles will exhibit equivalent cluster-forming behavior. Our results indicate that natural nanoparticles could form stable nanoclusters in groundwater that are likely to be highly mobile, with implications for the long-range transport of surface sorbed contaminants. (c) 2007 Elsevier Inc. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. Chapman Univ, Dept Phys Sci, Orange, CA 92866 USA. RP Gilbert, B (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. EM bgilbert@lbl.gov RI Gilbert, Benjamin/E-3182-2010 NR 57 TC 76 Z9 79 U1 7 U2 48 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD SEP 1 PY 2007 VL 313 IS 1 BP 152 EP 159 DI 10.1016/j.jcis.2007.04.038 PG 8 WC Chemistry, Physical SC Chemistry GA 194NU UT WOS:000248351900020 PM 17511999 ER PT J AU Wang, W Gu, BH Liang, LY AF Wang, Wei Gu, Baohua Liang, Liyuan TI Effect of anionic surfactants on synthesis and self-assembly of silica colloidal nanoparticles SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE silica; surfactant; colloids; nanoparticles; photonic crystals; self-assembly; thin film ID SIO2 NANOPARTICLES; MICELLAR-SOLUTIONS; RAMAN-SCATTERING; POROUS SILICA; PARTICLES; ADSORPTION; SPHERES; DISPERSIONS; TEMPERATURE; FABRICATION AB Effects of the anionic surfactants, sodium dodecyl sulfate and sodium oleate, on the formation and properties of silica colloidal nanoparticles were investigated. At a concentration of similar to 1 x 10(-3) M, adsorption of anionic Surfactants increased particle size, monodispersity, and negative surface charge density of synthesized silica particles. As uniformity of particle size and particle-particle interactions increase, colloidal photonic crystals readily self-assemble without extensive washing of the synthesized silica nanoparticles. The photonic crystals diffract light in the visible region according to Bragg's law. The assembled colloidal particle arrays exhibit a face-centered cubic structure in dried thin films. This study offers a new approach for producing ordered colloidal silica thin films. (c) 2007 Elsevier Inc. All rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Wang, W (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. EM wangw@ornl.gov RI Wang, Wei/B-5924-2012; Gu, Baohua/B-9511-2012; Liang, Liyuan/O-7213-2014 OI Gu, Baohua/0000-0002-7299-2956; Liang, Liyuan/0000-0003-1338-0324 NR 25 TC 21 Z9 22 U1 6 U2 33 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD SEP 1 PY 2007 VL 313 IS 1 BP 169 EP 173 DI 10.1016/j.jcis.2007.04.042 PG 5 WC Chemistry, Physical SC Chemistry GA 194NU UT WOS:000248351900022 PM 17512000 ER PT J AU Revil, A Linde, N Cerepi, A Jougnot, D Matthai, S Finsterle, S AF Revil, A. Linde, N. Cerepi, A. Jougnot, D. Matthaei, S. Finsterle, S. TI Electrokinetic coupling in unsaturated porous media SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE electro-osmosis; streaming potential; Stokes equation; Nernst-Planck equation; porous media; clay; saturation; capillary pressure ID ELECTRICAL-RESISTIVITY; FLOW; PERMEABILITY; TRANSPORT; EQUATIONS; SOILS; MODEL; ZONE AB We consider a charged porous material that is saturated by two fluid phases that are immiscible and continuous on the scale of a representative elementary volume. The wetting phase for the grains is water and the nonwetting phase is assumed to be an electrically insulating viscous fluid. We use a volume-averaging approach to derive the linear constitutive equations for the electrical current density as well as the seepage velocities of the wetting and nonwetting phases on the scale of a representative elementary volume. These macroscopic constitutive equations are obtained by volume-averaging Ampere's law together with the Nernst-Planck equation and the Stokes equations. The material properties entering the macroscopic constitutive equations are explicitly described as functions of the saturation of the water phase, the electrical formation factor, and parameters that describe the capillary pressure function, the relative permeability functions, and the variation of electrical conductivity with saturation. New equations are derived for the streaming potential and electro-osmosis coupling coefficients. A primary drainage and imbibition experiment is simulated numerically to demonstrate that the relative streaming potential coupling coefficient depends not only on the water saturation, but also on the material properties of the sample, as well as the saturation history. We also compare the predicted streaming potential coupling coefficients with experimental data from four dolomite core samples. Measurements on these samples include electrical conductivity, capillary pressure, the streaming potential coupling coefficient at various levels of saturation, and the permeability at saturation of the rock samples. We found very good agreement between these experimental data and the model predictions. (c) 2007 Elsevier Inc. All rights reserved. C1 Univ Paul Cezanne, CNRS, CEREGE, IRD, Aix En Provence, France. Swiss Fed Inst Technol, Inst Geophys, Zurich, Switzerland. Univ Bordeaux 3, Inst EGID, Pessac, France. ANDRA, Chatenay Malabry, France. Univ London Imperial Coll Sci Technol & Med, Dept Earth Sci & Engn, London, England. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. CNRS, ANDRA, GDR, FORPRO 0788, F-75700 Paris, France. Colorado Sch Mines, Golden, CO 80401 USA. RP Revil, A (reprint author), Univ Paul Cezanne, CNRS, CEREGE, IRD, Aix En Provence, France. EM revil@cerege.fr RI Linde, Niklas/A-9440-2008; Finsterle, Stefan/A-8360-2009; Jougnot, Damien/D-9186-2011; Matthai, Stephan/D-4702-2015 OI Linde, Niklas/0000-0003-1613-353X; Finsterle, Stefan/0000-0002-4446-9906; Jougnot, Damien/0000-0003-4950-5766; Matthai, Stephan/0000-0001-7470-8026 NR 34 TC 101 Z9 105 U1 1 U2 22 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD SEP 1 PY 2007 VL 313 IS 1 BP 315 EP 327 DI 10.1016/j.jcis.2007.03.037 PG 13 WC Chemistry, Physical SC Chemistry GA 194NU UT WOS:000248351900040 PM 17509604 ER PT J AU Walsh, T Torres, M AF Walsh, Timothy Torres, Monica TI Finite element methods for nonlinear acoustics in fluids SO JOURNAL OF COMPUTATIONAL ACOUSTICS LA English DT Article DE Kuznetsov equation; nonlinear acoustics; finite elements; resonances; Newton method ID WAVE PROPAGATION; SOLID SYSTEMS; FLOW PROBLEMS; MOVING GRIDS; DISSIPATION; SIMULATION; AMPLITUDE; EQUATIONS AB In this paper, weak formulations and finite element discretizations of the governing partial differential equations of three-dimensional nonlinear acoustics in absorbing fluids are presented. The fluid equations are considered in an Eulerian framework, rather than a displacement framework, since in the latter case the corresponding finite element formulations suffer from spurious modes and numerical instabilities. When taken with the governing partial differential equations of a solid body and the continuity conditions, a coupled formulation is derived. The change in solid/fluid interface conditions when going from a linear acoustic fluid to a nonlinear acoustic fluid is demonstrated. Finite element discretizations of the coupled problem are then derived, and verification examples are presented that demonstrate the correctness of the implementations. We demonstrate that the time step size necessary to resolve the wave decreases as steepening occurs. Finally, simulation results are presented on a resonating acoustic cavity, and a coupled elastic/acoustic system consisting of a fluid-filled spherical tank. C1 [Walsh, Timothy] Sandia Natl Labs, Albuquerque, NM 87185 USA. [Torres, Monica] Purdue Univ, Dept Math, W Lafayette, IN 47907 USA. RP Walsh, T (reprint author), Sandia Natl Labs, POB 5800,MS 0380, Albuquerque, NM 87185 USA. NR 22 TC 8 Z9 8 U1 2 U2 5 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0218-396X J9 J COMPUT ACOUST JI J. Comput. Acoust. PD SEP PY 2007 VL 15 IS 3 BP 353 EP 375 DI 10.1142/S0218396X0700338X PG 23 WC Acoustics; Mathematics, Interdisciplinary Applications SC Acoustics; Mathematics GA 327XN UT WOS:000257761900005 ER PT J AU Bailey, DH Borwein, JM Crandall, RE AF Bailey, D. H. Borwein, J. M. Crandall, R. E. TI Box integrals SO JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS LA English DT Article DE box integrals; multi-dimensional integrals; high-precision quadrature ID TRANSFORMATION AB By a "box integral" we mean here an expectation where r runs over the unit n-cube, with (q) over right arrow and s fixed, explicitly: integral(1)(0) ... integral(1)(0) ((r(1) - q(1))(2) + ... + (r(n) -q(n))(2))(s/2) dr(1) ... dr(n). The study of box integrals leads one naturally into several disparate fields of analysis. While previous studies have focused upon symbolic evaluation and asymptotic analysis of special cases (notably s = 1), we work herein more generally-in interdisciplinary fashion-developing results such as: (1) analytic continuation (in complex s), (2) relevant combinatorial identities, (3) rapidly converging series, (4) statistical inferences, (5) connections to mathematical physics, and (6) extreme-precision quadrature techniques appropriate for these integrals. These intuitions and results open up avenues of experimental mathematics, with a view to new conjectures and theorems on integrals of this type. (c) 2006 Elsevier B.V. All rights reserved. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Dalhousie Univ, Fac Comp Sci, Halifax, NS B3H 2W5, Canada. Reed Coll, Ctr Adv Computat, Portland, OR 97202 USA. RP Bailey, DH (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. EM dhbailey@lbl.gov; jborwein@cs.dal.ca; crandall@reed.edu RI Borwein, Jonathan/A-6082-2009; OI Borwein, Jonathan/0000-0002-1263-0646 NR 16 TC 14 Z9 14 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0427 J9 J COMPUT APPL MATH JI J. Comput. Appl. Math. PD SEP 1 PY 2007 VL 206 IS 1 BP 196 EP 208 DI 10.1016/j.cam.2006.06.010 PG 13 WC Mathematics, Applied SC Mathematics GA 185JE UT WOS:000247706500015 ER PT J AU Jung, YS Shao, YH Head-Gordon, M AF Jung, Yousung Shao, Yihan Head-Gordon, Martin TI Fast evaluation of scaled opposite spin second-order Moller-Plesset correlation energies using auxiliary basis expansions and exploiting sparsity SO JOURNAL OF COMPUTATIONAL CHEMISTRY LA English DT Article DE auxiliary basis expansions; locality; sparsity; natural blocking; SOS-MP2 ID ELECTRONIC-STRUCTURE CALCULATIONS; LINEAR SCALING COMPUTATION; PERTURBATION-THEORY; HARTREE-FOCK; MOLECULAR-SYSTEMS; LOCAL TRIATOMICS; BASIS-SETS; MATRIX; MP2; RESOLUTION AB The scaled opposite spin Moller-Plesset method (SOS-MP2) is an economical way of obtaining correlation energies that are computationally cheaper, and yet, in a statistical sense, of higher quality than standard MP2 theory, by introducing one empirical parameter. But SOS-MP2 still has a fourth-order scaling step that makes the method inapplicable to very large molecular systems. We reduce the scaling of SOS-MP2 by exploiting the sparsity of expansion coefficients and local integral matrices, by performing local auxiliary basis expansions for the occupied-virtual product distributions. To exploit sparsity of 3-index local quantities, we use a blocking scheme in which entire zero-rows and columns, for a given third global index, are deleted by comparison against a numerical threshold. This approach minimizes sparse matrix book-keeping overhead, and also provides sufficiently large submatrices after blocking, to allow efficient matrix-matrix multiplies. The resulting algorithm is formally cubic scaling, and requires only moderate computational resources (quadratic memory and disk space) and, in favorable cases, is shown to yield effective quadratic scaling behavior in the size regime we can apply it to. Errors associated with local fitting using the attenuated Coulomb metric and numerical thresholds in the blocking procedure are found to be insignificant in terms of the predicted relative energies. A diverse set of test calculations shows that the size of system where significant computational savings can be achieved depends strongly on the dimensionality of the system, and the extent of localizability of the molecular orbitals. (c) 2007 Wiley Periodicals, Inc. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Head-Gordon, M (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM mhg@cchem.berkeley.edu RI Jung, Yousung/D-1676-2010 OI Jung, Yousung/0000-0003-2615-8394 NR 47 TC 31 Z9 32 U1 0 U2 7 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0192-8651 J9 J COMPUT CHEM JI J. Comput. Chem. PD SEP PY 2007 VL 28 IS 12 BP 1953 EP 1964 DI 10.1002/jcc.20590 PG 12 WC Chemistry, Multidisciplinary SC Chemistry GA 191DA UT WOS:000248108900004 PM 17447248 ER PT J AU Evans, MH Caussanel, M Schrimpf, RD Pantelides, ST AF Evans, M. H. Caussanel, M. Schrimpf, R. D. Pantelides, Sokrates T. TI First-principles calculations of mobilities in ultrathin double-gate MOSFETs SO JOURNAL OF COMPUTATIONAL ELECTRONICS LA English DT Article DE Mobilities; Double-gate MOSFETs; Atomic-scale roughness AB For several decades, electron and hole mobilities have been adequately modeled using a semiclassical approximation of the Boltzamnn equation, using either an effective-mass expression or the bulk energy bands of Si to describe the carriers' kinetic energy. The Si-SiO2 interface is modeled by an infinite potential wall. Scattering mechanisms are described using phenomenological models. In recent years, with the advent of new materials and device structures (strained Si, alternate dielectrics, double-gate MOSFETs), the existing methods lack the necessary predictive power. Here we give an overview of a recently developed method to calculate mobilities from "first principles" using atomic-scale models of the interface and employing state-of-the-art density functional theory to construct scattering potentials and to compute mobilities without any adjustable parameters. Several examples are used to illustrate the method. C1 [Evans, M. H.; Pantelides, Sokrates T.] Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. [Caussanel, M.; Schrimpf, R. D.] Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN USA. [Pantelides, Sokrates T.] Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Evans, MH (reprint author), Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. EM mhevans@alum.mit.edu; m.caussanel@vanderbilt.edu; ron.schrimpf@vanderbilt.edu; pantelides@vanderbilt.edu RI Schrimpf, Ronald/L-5549-2013 OI Schrimpf, Ronald/0000-0001-7419-2701 NR 9 TC 1 Z9 1 U1 3 U2 9 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1569-8025 J9 J COMPUT ELECTRON JI J. Comput. Electron. PD SEP PY 2007 VL 6 IS 1-3 SI SI BP 85 EP 88 DI 10.1007/s10825-006-0070-1 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA V25JF UT WOS:000208473600020 ER PT J AU Sun, XH Byna, S Chen, Y AF Sun, Xian-He Byna, Surendra Chen, Yong TI Server-based data push architecture for multi-processor environments SO JOURNAL OF COMPUTER SCIENCE AND TECHNOLOGY LA English DT Article DE performance measurement; evaluation; modeling; simulation of multiple-processor system; cache memory ID SHARED-MEMORY MULTIPROCESSORS AB Data access delay is a major bottleneck in utilizing current high-end computing (HEC) machines. Prefetching, where data is fetched before CPU demands for it, has been considered as an effective solution to masking data access delay. However, current client-initiated prefetching strategies, where a computing processor initiates prefetching instructions, have many limitations. They do not work well for applications with complex, non-contiguous data access patterns. While technology advances continue to increase the gap between computing and data access performance, trading computing power for reducing data access delay has become a natural choice. In this paper, we present a server-based data-push approach and discuss its associated implementation mechanisms. In the server-push architecture, a dedicated server called Data Push Server (DPS) initiates and proactively pushes data closer to the client in time. Issues, such as what data to fetch, when to fetch, and how to push are studied. The SimpleScalar simulator is modified with a dedicated prefetching engine that pushes data for another processor to test DPS based prefetching. Simulation results show that L1 Cache miss rate can be reduced by up to 97% (71% on average) over a superscalar processor for SPEC CPU2000 benchmarks that have high cache miss rates. C1 IIT, Dept Comp Sci, Chicago, IL 60616 USA. Fermilab Natl Accelerator Lab, Comp Div, Batavia, IL 60510 USA. RP Sun, XH (reprint author), IIT, Dept Comp Sci, Chicago, IL 60616 USA. EM sun@iit.edu; sbyna@iit.edu; chenyon1@iit.edu RI Byna, Surendra/G-1622-2012; OI Byna, Surendra/0000-0003-3048-3448 NR 38 TC 4 Z9 6 U1 0 U2 1 PU SCIENCE PRESS PI BEIJING PA 16 DONGHUANGCHENGGEN NORTH ST, BEIJING 100717, PEOPLES R CHINA SN 1000-9000 EI 1860-4749 J9 J COMPUT SCI TECH-CH JI J. Comput. Sci. Technol. PD SEP PY 2007 VL 22 IS 5 BP 641 EP 652 DI 10.1007/s11390-007-9090-y PG 12 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA 218IN UT WOS:000250009300001 ER PT J AU Sullivan, S Cooray, A Holz, DE AF Sullivan, Scott Cooray, Asantha Holz, Daniel E. TI Narrowing constraints with type Ia supernovae: converging on a cosmological constant SO JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS LA English DT Article DE dark energy theory; cosmological constant experiments ID EQUATION-OF-STATE; HUBBLE-SPACE-TELESCOPE; QUINTESSENCE; PROBE AB We apply a parameterization-independent approach to fitting the dark energy equation-of-state (EOS). Utilizing the latest type Ia supernova data, combined with results from the cosmic microwave background and baryon acoustic oscillations, we find that the dark energy is consistent with a cosmological constant. We establish independent estimates of the evolution of the dark energy EOS by diagonalizing the covariance matrix. We find three independent constraints, which taken together imply that the equation of state is more negative than -0.2 at the 68% confidence level in the redshift range 0 < z < 1.8, independent of the. at universe assumption. Our estimates argue against previous claims of dark energy 'metamorphosis', where the EOS was found to be strongly varying at low redshifts. Our results are inconsistent with extreme models of dynamical dark energy, both in the form of 'freezing' models where the dark energy EOS begins with a value greater than -0.2 at z > 1.2 and rolls to a value of -1 today, and 'thawing' models where the EOS is near -1 at high redshifts, but rapidly evolves to values greater than -0.85 at z < 0.2. Finally, we propose a parameterization-independent figure of merit (FOM), to help assess the ability of future surveys to constrain dark energy. While the more common FOM presumes a specific dark energy parameterization with two parameters, we suggest a binning approach to evaluate dark energy constraints with a minimum number of assumptions. C1 Univ Calif Irvine, Ctr Cosm, Dept Phys, Irvine, CA 92697 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. RP Sullivan, S (reprint author), Univ Calif Irvine, Ctr Cosm, Dept Phys, Irvine, CA 92697 USA. EM ssulliva@uci.edu; acooray@uci.edu; deholz@kicp.uchicago.edu NR 45 TC 32 Z9 32 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 1475-7516 J9 J COSMOL ASTROPART P JI J. Cosmol. Astropart. Phys. PD SEP PY 2007 IS 9 AR 004 DI 10.1088/1475-7516/2007/09/004 PG 16 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 215LX UT WOS:000249811000018 ER PT J AU Cederberg, JG AF Cederberg, J. G. TI Self-assembled quantum dot formation during the growth of In0.4Ga0.6As on GaAS(001) by metal-organic vapor phase epitaxy: The role of In segregation SO JOURNAL OF CRYSTAL GROWTH LA English DT Article DE low-dimensional structures; nanostructures; segregation; metal-organic vapor phase epitaxy; semiconducting ternary compounds ID MOLECULAR-BEAM EPITAXY; SURFACE SEGREGATION; INGAAS; GAAS; SEMICONDUCTORS; TEMPERATURE; RELAXATION; TRANSITION; DEPOSITION; LAYERS AB The stabilization of planar In0.4Ga0.6As on GaAs, above thickness typically reported to undergo spontaneous island formation, has been observed. The effect of growth temperature, AsH3 partial pressure, and In0.4Ga0.6As thickness on island size and density was evaluated. Planar films are stabilized by low growth temperatures and high AsH3 partial pressures. Spontaneous island formation is enhanced by high growth temperatures and low AsH3 partial pressures. The results presented are interpreted within the phenomenology of In segregation to the surface, which has been identified previously for the InGaAs/GaAs system. Based on equilibrium models for the critical thickness for island formation, the critical segregation layer thickness for island formation is predicted to be 0.6 nm. Published by Elsevier B.V. C1 Sandia Natl Labs, Albuquerque, NM 87123 USA. RP Cederberg, JG (reprint author), Sandia Natl Labs, 1515 Eubank Blvd SE, Albuquerque, NM 87123 USA. EM jgceder@sandia.gov NR 26 TC 8 Z9 8 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD SEP 1 PY 2007 VL 307 IS 1 BP 44 EP 50 DI 10.1016/j.jcrysgro.2007.05.019 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 215IJ UT WOS:000249801600009 ER PT J AU Habelitz, S Rodriguez, BJ Marshall, SJ Marshall, GW Kalinin, SV Gruverman, A AF Habelitz, S. Rodriguez, B. J. Marshall, S. J. Marshall, G. W. Kalinin, S. V. Gruverman, A. TI Peritubular dentin lacks piezoelectricity SO JOURNAL OF DENTAL RESEARCH LA English DT Article DE atomic force microscopy; piezoelectricity; dentin; collagen ID COLLAGEN FIBRILS; FORCE MICROSCOPY; CONSTITUENTS; MATRIX AB Dentin is a mesenchymal tissue, and, as such, is based on a collagenous matrix that is reinforced by apatite mineral. Collagen fibrils show piezoelectricity, a phenomenon that is used by piezoresponse force microscopy ( PFM) to obtain high-resolution images. We applied PFM to image human dentin with 10-nm resolution, and to test the hypothesis that zones of piezoactivity, indicating the presence of collagen fibrils, can be distinguished in dentin. Piezoelectricity was observed by PFM in the dentin intertubular matrix, while the peritubular dentin remained without response. High-resolution imaging of chemically treated intertubular dentin attributed the piezoelectric effect to individual collagen fibrils that differed in the signal strength, depending on the fibril orientation. This study supports the hypothesis that peritubular dentin is a non-collagenous tissue and is thus an exception among mineralized tissues that derive from the mesenchyme. C1 Univ Calif San Francisco, Dept Prevent & Restorat Dent Sci, San Francisco, CA 94143 USA. Oak Ridge Natl Lab, Condensed Matter Sci Div, Oak Ridge, TN 37831 USA. N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. RP Habelitz, S (reprint author), Univ Calif San Francisco, Dept Prevent & Restorat Dent Sci, Box 0758,707 Parnassus Ave, San Francisco, CA 94143 USA. EM Stefan.habelitz@ucsf.edu RI Kalinin, Sergei/I-9096-2012; Rodriguez, Brian/A-6253-2009; Gruverman, alexei/P-3537-2014 OI Kalinin, Sergei/0000-0001-5354-6152; Rodriguez, Brian/0000-0001-9419-2717; Gruverman, alexei/0000-0003-0492-2750 FU NIDCR NIH HHS [P01 DE09859, P01 DE009859, R01 DE016849, R01 DE016849-01A1] NR 21 TC 22 Z9 22 U1 0 U2 7 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0022-0345 EI 1544-0591 J9 J DENT RES JI J. Dent. Res. PD SEP PY 2007 VL 86 IS 9 BP 908 EP 911 PG 4 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 203ZS UT WOS:000249013200020 PM 17720865 ER PT J AU Erdin, S Lin, Y Halley, JW Zapol, P Redfern, P Curtiss, L AF Erdin, Serkan Lin, You Halley, J. W. Zapol, Peter Redfern, Paul Curtiss, Larry TI Self-consistent tight binding molecular dynamics study of TiO2 nanoclusters in water SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Article DE rutile; anatase; water; nanocrystals; simulation ID TITANIUM-DIOXIDE; ELECTRONIC-STRUCTURE; SURFACE; NANOPARTICLES; ANATASE; REACTIVITY; MODEL AB Self-consistent tight binding molecular dynamics studies of TiO2, anatase and rutile nanoclusters in dissociable water are reported. It is found that the structure of the particle expands as a result of interaction between the particle's surface and water. Water molecules dissociate at the nanoparticle surface during simulation. (c) 2007 Elsevier B.V. All rights reserved. C1 No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ S Florida, Dept Phys, Tampa, FL 33620 USA. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Argonne Natl Lab, Ctr Nanoscale Mat, Div Mat & Chem Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Halley, JW (reprint author), No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. EM woods@woods1.spa.umn.edu RI Zapol, Peter/G-1810-2012; Erdin, Serkan/B-4988-2008 OI Zapol, Peter/0000-0003-0570-9169; Erdin, Serkan/0000-0001-6587-2625 NR 30 TC 10 Z9 10 U1 1 U2 10 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 1572-6657 EI 1873-2569 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD SEP 1 PY 2007 VL 607 IS 1-2 BP 147 EP 157 DI 10.1016/j.jelechem.2007.03.016 PG 11 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA 206IM UT WOS:000249177100019 ER PT J AU Illindala, M Siddiqui, A Venkataramanan, G Marnay, C AF Illindala, Mahesh Siddiqui, Afzal Venkataramanan, Giri Marnay, Chris TI Localized aggregation of diverse energy sources for rural electrification using microgrids SO JOURNAL OF ENERGY ENGINEERING-ASCE LA English DT Article AB Extension of electrical service to large rural populations in developing nations is a key requirement to realize human development goals set forth by international agencies. This paper presents the case for distributed generation in the form of microgrids, which should be the preferred path towards rural electrification in developing communities and a vital complement to expensive centralized grid expansion. The technical features of frequency and voltage control for distributed generation devices in a microgrid are discussed along with a presentation of their stability attributes. Computer simulation results and experimental results from a laboratory scale microgrid are also presented. C1 Caterpillar Inc, Peoria, IL 61656 USA. UCL, Dept Stat Sci, London WC1E 6BT, England. Univ Wisconsin, Dept Elect & Comp Engn, Madison, WI 54706 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Illindala, M (reprint author), Caterpillar Inc, Tech Ctr Bldg G,41-TC G 855, Peoria, IL 61656 USA. EM illindala_mahesh_s@cat.com; afzal@stats.ucl.ac.uk; giri@engr.wisc.edu; c_marnay@lbl.gov RI Illindala, Mahesh/B-2822-2013 OI Illindala, Mahesh/0000-0002-2015-1338 NR 44 TC 6 Z9 6 U1 0 U2 8 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-9402 J9 J ENERG ENG-ASCE JI J. Energy Eng.-ASCE PD SEP PY 2007 VL 133 IS 3 BP 121 EP 131 DI 10.1061/(ASCE)0733-9402(2007)133:3(121) PG 11 WC Energy & Fuels; Engineering, Civil SC Energy & Fuels; Engineering GA 203JN UT WOS:000248971000003 ER PT J AU Siddiqui, AS Marnay, C Firestone, RM Zhou, N AF Siddiqui, Afzal S. Marnay, Chris Firestone, Ryan M. Zhou, Nan TI Distributed generation with heat recovery and storage SO JOURNAL OF ENERGY ENGINEERING-ASCE LA English DT Article AB Electricity produced by distributed energy resources (DER) located close to end-use loads has the potential to meet consumer requirements more efficiently than the existing centralized grid. Installation of DER allows consumers to circumvent the costs associated with transmission congestion and other nonenergy costs of electricity delivery and potentially to take advantage of market opportunities to purchase energy when attractive. On-site, single-cycle thermal power generation is typically less efficient than central station generation, but by avoiding nonfuel costs of grid power and by utilizing combined heat and power applications, i.e., recovering heat from small-scale on-site thermal generation to displace fuel purchases, DER can become attractive to a strictly cost-minimizing consumer. In previous efforts, the decisions facing typical commercial consumers have been addressed using a mixed-integer linear program, the DER customer adoption model (DER-CAM). Given the site's energy loads, utility tariff structure, and information (both technical and financial) on candidate DER technologies, DER-CAM minimizes the overall energy cost for a test year by selecting the units to install and determining their hourly operating schedules. In this paper, the capabilities of DER-CAM are enhanced by the inclusion of the option to store recovered low-grade heat. By being able to keep an inventory of heat for use in subsequent periods, sites are able to lower costs even further by reducing lucrative peak-shaving generation, while relying on storage to meet heat loads. This and other effects of storage are demonstrated by analysis of five typical commercial buildings in San Francisco, California, in the United States, and an estimate of the cost per unit capacity of heat storage is calculated. C1 UCL, Dept Stat Sci, London WC1E 6BT, England. Univ Coll Dublin, Michael Smurfit Grad Sch Business, Dublin 2, Ireland. Ernest Orlando Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Siddiqui, AS (reprint author), UCL, Dept Stat Sci, London WC1E 6BT, England. EM afzal@stats.ucl.ac.uk; c_marnay@lbl.gov; rmfirestone@lbl.gov; nzhou@lbl.gov NR 22 TC 20 Z9 20 U1 0 U2 18 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-9402 J9 J ENERG ENG-ASCE JI J. Energy Eng.-ASCE PD SEP PY 2007 VL 133 IS 3 BP 181 EP 210 DI 10.1061/(ASCE)0733-9402(2007)133:3(181) PG 30 WC Energy & Fuels; Engineering, Civil SC Energy & Fuels; Engineering GA 203JN UT WOS:000248971000009 ER PT J AU Hendricks, TJ AF Hendricks, Terry J. TI Thermal system interactions in thermoelectric energy recovery systems ontimizing advanced SO JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB Energy recovery is gaining importance in various transportation and industrial process applications because of rising energy costs and geopolitical uncertainties impacting basic energy supplies. Various advanced thermoelectric (TE) materials have properties that are inherently advantageous for particular TE energy recovery applications. Skutterudites, zero- and one-dimensional quantum-well materials, and thin-film superlattice materials are providing enhanced opportunities for advanced TE energy recovery in transportation and industrial processes. This work demonstrates (1) the potential for advanced thermoelectric systems in vehicle energy recovery and (2) the inherently complex interaction between thermal system performance and thermoelectric device optimization in energy recovery. Potential power generation at specific exhaust temperature levels and for various heat exchanger performance levels is presented showing the current design sensitivities using different TE material sets. Mathematical relationships inherently linking optimum TE design variables and the thermal systems design (i.e., heat exchangers and required mass flow rates) are also investigated and characterized. C1 Pacific NW Natl Lab, Energy Sci & Technol Directorate, Richland, WA 99352 USA. RP Hendricks, TJ (reprint author), Pacific NW Natl Lab, Energy Sci & Technol Directorate, 902 Battelle Blvd, Richland, WA 99352 USA. NR 16 TC 24 Z9 24 U1 0 U2 7 PU ASME PI NEW YORK PA TWO PARK AVE, NEW YORK, NY 10016-5990 USA SN 0195-0738 J9 J ENERG RESOUR-ASME JI J. Energy Resour. Technol.-Trans. ASME PD SEP PY 2007 VL 129 IS 3 BP 223 EP 231 DI 10.1115/1.2751504 PG 9 WC Energy & Fuels SC Energy & Fuels GA 206HT UT WOS:000249175200006 ER PT J AU Canan, B Olhoeft, GR Smith, WA AF Canan, Birsen Olhoeft, Gary R. Smith, William A. TI Experimental monitoring of Cr(VI) bio-reduction using electrochemical geophysics SO JOURNAL OF ENVIRONMENTAL AND ENGINEERING GEOPHYSICS LA English DT Article ID HEXAVALENT CHROMIUM; SOILS; CHEMISTRY; FATE AB Many Department of Energy (DOE) sites are contaminated with highly carcinogenic hexavalent chromium (Cr(VI)). In this research, we explore the feasibility of applying complex resistivity to the detection and monitoring of microbially-induced reduction of hexavalent chromium (Cr(VI)) to a less toxic form (Cr(III)). We hope to measure the change in ionic concentration that occurs during this reduction reaction. This form of reduction promises to be an attractive alternative to more expensive remedial treatment methods. The specific goal of this research is to define the minimum and maximum concentration of the chemical and biological compounds in contaminated samples for which the Cr(VI) - Cr(III) reduction processes could be detected via complex resistivity. There are three sets of experiments, each comprised of three sample columns. The first experiment compares three concentrations of Cr(VI) at the same bacterial cell concentration. The second experiment establishes background samples with, and without, Cr(VI) and bacterial cells. The third experiment examines the influence of three different bacterial cell counts on the same concentration of Cr(VI). A polarization relaxation mechanism was observed between 10 and 50 Hz. The polarization mechanism, unfortunately, was not unique to bio-chemically active samples. Spectral analysis of complex resistivity data, however, showed that the frequency where the phase minimum occurred was not constant for bio-chemically active samples throughout the experiment. Significant shift in phase minima occurred between 10 to 20 Hz from the initiation to completion of Cr(VI) reduction. This phenomenon was quantified using the Cole-Cole model and the Marquardt-Levenberg nonlinear least square minimization method. The data suggest that the relaxation time and the time constant of this relaxation are the Cole-Cole parameters most sensitive to changes in biologically-induced reduction of Cr(VI). C1 TDM Consulting, Boise, ID 83717 USA. Colorado Sch Mines, Dept Geophys, Golden, CO 80401 USA. Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Canan, B (reprint author), TDM Consulting, POB 170077, Boise, ID 83717 USA. EM BirsenCanan@yahoo.com NR 34 TC 1 Z9 1 U1 0 U2 2 PU ENVIRONMENTAL ENGINEERING GEOPHYSICAL SOC PI DENVER PA 1720 SOUTH BELLAIRE, STE 110, DENVER, CO 80222-433 USA SN 1083-1363 J9 J ENVIRON ENG GEOPH JI J. Environ. Eng. Geophys. PD SEP PY 2007 VL 12 IS 3 BP 255 EP 266 DI 10.2113/JEEG12.3.255 PG 12 WC Geochemistry & Geophysics; Engineering, Geological SC Geochemistry & Geophysics; Engineering GA 213KS UT WOS:000249666400002 ER PT J AU Granite, EJ Freeman, MC Hargis, RA O'Dowd, WJ Pennline, HW AF Granite, Evan J. Freeman, Mark C. Hargis, Richard A. O'Dowd, William J. Pennline, Henry W. TI The thief process for mercury removal from flue gas SO JOURNAL OF ENVIRONMENTAL MANAGEMENT LA English DT Article DE mercury; flue gas; sorbent; activated carbon; thief process ID CATALYSTS AB The Thief Process is a cost-effective variation to activated carbon injection (ACI) for removal of mercury from flue gas. In this scheme, partially combusted coal from the furnace of a pulverized coal power generation plant is extracted by a lance and then re-injected into the ductwork downstream of the air preheater. Recent results on a 500-lb/h pilot-scale combustion facility show similar removals of mercury for both the Thief Process and ACI The tests conducted to date at laboratory, bench, and pilot-scales demonstrate that the Thief sorbents exhibit capacities for mercury from flue gas streams that are comparable to those exhibited by commercially available activated carbons. A patent for the process was issued in February 2003. The Thief sorbents are cheaper than commercially-available activated carbons; exhibit excellent capacities for mercury; and the overall process holds great potential for reducing the cost of mercury removal from flue gas. The Thief Process was licensed to Mobotec USA, Inc. in May of 2005. (c) 2006 Elsevier Ltd. All rights reserved. C1 US DOE, Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. RP Granite, EJ (reprint author), US DOE, Natl Energy Technol Lab, POB 10940 MS 58-106, Pittsburgh, PA 15236 USA. EM evan.granite@net1.doe.gov NR 16 TC 52 Z9 55 U1 0 U2 16 PU ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0301-4797 EI 1095-8630 J9 J ENVIRON MANAGE JI J. Environ. Manage. PD SEP PY 2007 VL 84 IS 4 BP 628 EP 634 DI 10.1016/j.jenvman.2006.06.022 PG 7 WC Environmental Sciences SC Environmental Sciences & Ecology GA 196UW UT WOS:000248508700022 PM 16959396 ER PT J AU Wargacki, SP Lewis, LA Dadmun, MD AF Wargacki, Stephen P. Lewis, Linda A. Dadmun, Mark D. TI Understanding the chemistry of the development of latent fingerprints by superglue fuming SO JOURNAL OF FORENSIC SCIENCES LA English DT Article DE forensic science; cyanoacrylates; fingerprints; polymerization; initiation ID ANIONIC-POLYMERIZATION; BUTYL CYANOACRYLATE; TETRABUTYLAMMONIUM SALTS; INITIATION PROCESSES; RATE CONSTANTS; ACIDS AB Cyanoacrylate fuming is a widely used forensic tool for the development of latent fingerprints, however the mechanistic details of the reaction between the fingerprint residue and the cyanoacrylate vapor are not well understood. Here the polymerization of ethyl-cyanoacrylate vapor by sodium lactate or alanine solutions, two of the major components in fingerprint residue, has been examined by monitoring the time dependence of the mass uptake and resultant polymer molecular weight characteristics. This data provides insight into the molecular level actions in the efficient development of latent fingerprints by superglue fuming. The results show that the carboxylate moiety is the primary initiator of the polymerization process and that a basic environment inhibits chain termination while an acidic environment promotes it. The results also indicate that water cannot be the primary initiator in this forensic technique. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. RP Dadmun, MD (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. EM dad@utk.edu OI Dadmun, Mark/0000-0003-4304-6087 NR 24 TC 32 Z9 32 U1 8 U2 55 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD SEP PY 2007 VL 52 IS 5 BP 1057 EP 1062 DI 10.1111/j.1556-4029.2007.00527.x PG 6 WC Medicine, Legal SC Legal Medicine GA 208LT UT WOS:000249321500008 PM 17680999 ER PT J AU Straatman, AG Gallego, NC Yu, Q Betchen, L AF Straatman, A. G. Gallego, N. C. Yu, Q. Betchen, L. TI Forced convection heat transfer and hydraulic losses in graphitic foam SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE graphitic foam; forced convection; thermal non-equilibrium; thermal dispersion ID THERMAL-CONDUCTIVITY; CARBON FOAMS; METAL FOAMS; MODEL; FLOW AB Experiments and computations are presented to quantify the convective heat transfer and the hydraulic loss that is obtained by forcing water through blocks of graphitic foam (GF) heated from one side. Experiments have been conducted in a small-scale water tunnel instrumented to measure the pressure drop and the temperature rise of water passing through the foam and the base temperature and heat flux into the foam block. The experimental data were then used to calibrate a thermal non-equilibrium finite-volume model to facilitate comparisons between GF and aluminum foam. Comparisons of the pressure drop indicate that both normal and compressed aluminum foams are significantly more permeable than GF. Results of the heat transfer indicate that the maximum possible heat dissipation from a given surface is reached using very thin layers of aluminum foam due to the inability of the foam to entrain heat into its internal structure. In contrast, graphitic foam is able to entrain heat deep into the foam structure due to its high extended surface efficiency and thus much more heat can be transferred from a given surface area. The higher extended surface efficiency is mainly due to the combination of moderate porosity and higher solid-phase conductivity. C1 Univ Western Ontario, Dept Mech & Mat Engn, London, ON N6A 5B9, Canada. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Thermalcentr Inc, London, ON N6J 3J5, Canada. RP Straatman, AG (reprint author), Univ Western Ontario, Dept Mech & Mat Engn, London, ON N6A 5B9, Canada. OI Gallego, Nidia/0000-0002-8252-0194 NR 12 TC 16 Z9 16 U1 0 U2 4 PU ASME PI NEW YORK PA TWO PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 EI 1528-8943 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD SEP PY 2007 VL 129 IS 9 BP 1237 EP 1245 DI 10.1115/1.2739621 PG 9 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 217TY UT WOS:000249971400015 ER PT J AU Aharony, O Kachru, S AF Aharony, Ofer Kachru, Shamit TI Stringy instantons and cascading quivers SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE supersymmetric gauge theory; D-branes; brane dynamics in gauge theories; nonperturbative effects ID CONFORMAL FIELD-THEORIES; GAUGE-THEORIES; SUPERPOTENTIALS; VACUA AB D-brane instantons can perturb the quantum field theories on space-time filling D-branes by interesting operators. In some cases, these D-brane instantons are novel "stringy" effects (not interpretable directly as instanton effects in the low-energy quantum field theory), while in others the D-brane instantons can be directly interpreted as field theory effects. In this note, we describe a situation where both perspectives are available, by studying stringy instantons in quivers which arise at simple Calabi-Yau singularities. We show that a stringy instanton which wraps an unoccupied node of the quiver, and gives rise to a non-perturbative mass in the space-time field theory, can be reinterpreted as a conventional gauge theory effect by going up in an appropriate renormalization group cascade. Interestingly, in the cascade, the contribution of the stringy instanton does not come from gauge theory instantons but from strong coupling dynamics. C1 Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, SLAC, Stanford, CA 94305 USA. RP Aharony, O (reprint author), Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. EM Ofer.Aharony@weizmann.ac.il; skachru@stanford.edu NR 41 TC 26 Z9 26 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD SEP PY 2007 IS 9 AR 060 PG 15 WC Physics, Particles & Fields SC Physics GA 215DP UT WOS:000249788800069 ER PT J AU Jackson, MG AF Jackson, Mark G. TI Interactions of cosmic superstrings SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE string theory and cosmic strings; flux compactifications ID MACROSCOPIC FUNDAMENTAL STRINGS; COLLISIONS AB We develop methods by which cosmic superstring interactions can be studied in detail. These include the reconnection probability and emission of radiation such as gravitons or small string loops. Loop corrections to these are discussed, as well as relations hips to (p,q)-strings. These tools should allow a phenomenological study of string models in anticipation of up coming experiments sensitive to cosmic string radiation. C1 Fermilab Natl Accelerator Lab, Ctr Particle Astrophys, Batavia, IL 60510 USA. RP Jackson, MG (reprint author), Fermilab Natl Accelerator Lab, Ctr Particle Astrophys, POB 500, Batavia, IL 60510 USA. EM markj@fnal.gov NR 40 TC 14 Z9 14 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD SEP PY 2007 IS 9 AR 035 PG 19 WC Physics, Particles & Fields SC Physics GA 215DP UT WOS:000249788800094 ER PT J AU Lunghi, E Soni, A AF Lunghi, Enrico Soni, Amarjit TI Footprints of the beyond in flavor physics: possible role of the top two Higgs doublet model SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Review DE CP violation; beyond standard model; B-physics; rare decays ID CP ASYMMETRIES; STANDARD MODEL; B-DECAYS; QCD FACTORIZATION; SYMMETRY-BREAKING; MAGNETIC-MOMENTS; MATRIX-ELEMENTS; MESON DECAYS; QUARK; OPERATORS AB The B-factories results provide an impressive confirmation of the Standard Model (SM) description of flavor and CP violation. Nevertheless, as more data were accumulated, deviations in the 2.5-3.5 sigma range have emerged pointing to the exciting possibility of new CP-odd phase(s) and flavor violating parameters in B-decays. Primarily this seems to be the case in the time dependent CP asymmetries in penguin dominated modes (e.g. B --> phi(eta')K-s).We discuss these and other deviations from the SM and, as an illustration of possible new physics scenarios, we examine the role of the Top Two Higgs Doublet Model. This is a simple extension of the SM obtained by adding second Higgs doubletin which the Yukawa interactions of the two Higgs doublets areas signed in order to naturally account for the large top-quark mass. Of course, many other extensions of the Standard Model could also account for these experimental deviations. Clearly if one takes these deviations seriously then some new particles in the approximate to 300 GeV to approximate to few TeV range with associated new CP-odd phase(s) are needed. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Lunghi, E (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM lunghi@fnal.gov; soni@quark.phy.bnl.gov NR 108 TC 29 Z9 29 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD SEP PY 2007 IS 9 AR 053 DI 10.1088/1126-6708/2007/09/053 PG 39 WC Physics, Particles & Fields SC Physics GA 215DP UT WOS:000249788800076 ER PT J AU Schael, S Barate, R Bruneliere, R Bonis, I Decamp, D Goy, C Jezequel, S Lees, JP Martin, F Merele, E Minard, MN Pietrzyk, B Trocme, B Bravo, S Casado, MP Chmeissani, M Crespo, JM Fernandez, E Fernandez-Bosman, M Garrido, L Martinez, M Pacheco, A Ruiz, H Colaleo, A Creanza, D De Filippis, N de Palma, M Iaselli, G Maggi, G Maggi, M Nuzzo, S Ranieri, A Raso, G Ruggieri, F Selvaggi, G Silvestris, L Tempesta, P Tricomi, A Zito, G Huang, X Lin, J Ouyang, Q Wang, T Xie, Y Xu, R Xue, S Zhang, J Zhang, L Zhao, W Abbaneo, D Barklow, T Buchmuller, O Cattaneo, M Clerbaux, B Drevermann, H Forty, RW Frank, M Gianotti, F Hansen, JB Harvey, J Hutchcroft, DE Janot, P Jost, B Kado, M Mato, P Moutoussi, A Ranjard, F Rolandi, L Schlatter, D Teubert, F Valassi, A Videau, I Badaud, F Dessagne, S Falvard, A Fayolle, D Gay, P Jousset, J Michel, B Monteil, S Pallin, D Pascolo, JM Perret, P Hansen, JD Hansen, JR Hansen, PH Kraan, AC Nilsson, BS Kyriakis, A Markou, C Simopoulou, E Vayaki, A Zachariadou, K Blondel, A Brient, JC Machefert, F Rougee, A Videau, H Ciulli, V Focardi, E Parrini, G Antonelli, A Antonelli, M Bencivenni, G Bossi, F Capon, G Cerutti, F Chiarella, V Laurelli, P Mannocchi, G Murtas, GP Passalacqua, L Kennedy, J Lynch, JG Negus, P O'Shea, V Thompson, AS Wasserbaech, S Cavanaugh, R Dhamotharan, S Geweniger, C Hanke, P Hepp, V Kluge, EE Putzer, A Stenzel, H Tittel, K Wunsch, M Beuselinck, R Cameron, W Davies, G Dornan, PJ Girone, M Marinelli, N Nowell, J Rutherford, SA Sedgbeer, JK Thompson, JC White, R Ghete, VM Girtler, P Kneringer, E Kuhn, D Rudolph, G Bouhova-Thacker, E Bowdery, CK Clarke, DP Ellis, G Finch, AJ Foster, F Hughes, G Jones, RWL Pearson, MR Robertson, NA Sloan, T Smizanska, M van der Aa, O Delaere, C Leibenguth, G Lemaitre, V Blumenschein, U Holldorfer, F Jakobs, K Kayser, F Muller, AS Renk, B Sander, HG Schmeling, S Wachsmuth, H Zeitnitz, C Ziegler, T Bonissent, A Coyle, P Curtil, C Ealet, A Fouchez, D Payre, P Tilquin, A Ragusa, F David, A Dietl, H Ganis, G Huttmann, K Lutjens, G Manner, W Moser, HG Settles, R Villegas, M Wolf, G Boucrot, J Callot, O Davier, M Duflot, L Grivaz, JF Heusse, P Jacholkowska, A Serin, L Veillet, JJ Azzurri, P Bagliesi, G Boccali, T Foa, L Giammanco, A Giassi, A Ligabue, F Messineo, A Palla, F Sanguinetti, G Sciaba, A Sguazzoni, G Spagnolo, P Tenchini, R Venturi, A Verdini, P Awunor, O Blair, GA Cowan, G Garcia-Bellido, A Green, MG Medcalf, T Misiejuk, A Strong, JA Teixeira-Dias, P Clifft, RW Edgecock, TR Norton, PR Tomalin, IR Ward, JJ Bloch-Devaux, B Boumediene, D Colas, P Fabbro, B Lancon, E Lemaire, MC Locci, E Perez, P Rander, J Tuchming, B Vallage, B Litke, AM Taylor, G Booth, CN Cartwright, S Combley, F Hodgson, PN Lehto, M Thompson, LF Bohrer, A Brandt, S Grupen, C Hess, J Ngac, A Prange, G Borean, C Giannini, G He, H Putz, J Rothberg, J Armstrong, SR Berkelman, K Cranmer, K Ferguson, DPS Gao, Y Gonzalez, S Hayes, OJ Hu, H Jin, S Kile, J McNamara, PA Nielsen, J Pan, YB von Wimmersperg-Toeller, JH Wiedenmann, W Wu, J Wu, SL Wu, X Zobernig, G Dissertori, G AF Schael, S. Barate, R. Bruneliere, R. De Bonis, I. Decamp, D. Goy, C. Jezequel, S. Lees, J.-P. Martin, F. Merele, E. Minard, M.-N. Pietrzyk, B. Trocme, B. Bravo, S. Casado, M. P. Chmeissani, M. Crespo, J. M. Fernandez, E. Fernandez-Bosman, M. Garrido, Ll. Martinez, M. Pacheco, A. Ruiz, H. Colaleo, A. Creanza, D. De Filippis, N. de Palma, M. Iaselli, G. Maggi, G. Maggi, M. Nuzzo, S. Ranieri, A. Raso, G. Ruggieri, F. Selvaggi, G. Silvestris, L. Tempesta, P. Tricomi, A. Zito, G. Huang, X. Lin, J. Ouyang, Q. Wang, T. Xie, Y. Xu, R. Xue, S. Zhang, J. Zhang, L. Zhao, W. Abbaneo, D. Barklow, T. Buchmueller, O. Cattaneo, M. Clerbaux, B. Drevermann, H. Forty, R. W. Frank, M. Gianotti, F. Hansen, J. B. Harvey, J. Hutchcroft, D. E. Janot, P. Jost, B. Kado, M. Mato, P. Moutoussi, A. Ranjard, F. Rolandi, L. Schlatter, D. Teubert, F. Valassi, A. Videau, I. Badaud, F. Dessagne, S. Falvard, A. Fayolle, D. Gay, P. Jousset, J. Michel, B. Monteil, S. Pallin, D. Pascolo, J. M. Perret, P. Hansen, J. D. Hansen, J. R. Hansen, P. H. Kraan, A. C. Nilsson, B. S. Kyriakis, A. Markou, C. Simopoulou, E. Vayaki, A. Zachariadou, K. Blondel, A. Brient, J.-C. Machefert, F. Rouge, A. Videau, H. Ciulli, V. Focardi, E. Parrini, G. Antonelli, A. Antonelli, M. Bencivenni, G. Bossi, F. Capon, G. Cerutti, F. Chiarella, V. Laurelli, P. Mannocchi, G. Murtas, G. P. Passalacqua, L. Kennedy, J. Lynch, J. G. Negus, P. O'Shea, V. Thompson, A. S. Wasserbaech, S. Cavanaugh, R. Dhamotharan, S. Geweniger, C. Hanke, P. Hepp, V. Kluge, E. E. Putzer, A. Stenzel, H. Tittel, K. Wunsch, M. Beuselinck, R. Cameron, W. Davies, G. Dornan, P. J. Girone, M. Marinelli, N. Nowell, J. Rutherford, S. A. Sedgbeer, J. K. Thompson, J. C. White, R. Ghete, V. M. Girtler, P. Kneringer, E. Kuhn, D. Rudolph, G. Bouhova-Thacker, E. Bowdery, C. K. Clarke, D. P. Ellis, G. Finch, A. J. Foster, F. Hughes, G. Jones, R. W. L. Pearson, M. R. Robertson, N. A. Sloan, T. Smizanska, M. van der Aa, O. Delaere, C. Leibenguth, G. Lemaitre, V. Blumenschein, U. Hoelldorfer, F. Jakobs, K. Kayser, F. Mueller, A.-S. Renk, B. Sander, H.-G. Schmeling, S. Wachsmuth, H. Zeitnitz, C. Ziegler, T. Bonissent, A. Coyle, P. Curtil, C. Ealet, A. Fouchez, D. Payre, P. Tilquin, A. Ragusa, F. David, A. Dietl, H. Ganis, G. Huettmann, K. Luetjens, G. Maenner, W. Moser, H.-G. Settles, R. Villegas, M. Wolf, G. Boucrot, J. Callot, O. Davier, M. Duflot, L. Grivaz, J.-F. Heusse, Ph. Jacholkowska, A. Serin, L. Veillet, J.-J. Azzurri, P. Bagliesi, G. Boccali, T. Foa, L. Giammanco, A. Giassi, A. Ligabue, F. Messineo, A. Palla, F. Sanguinetti, G. Sciaba, A. Sguazzoni, G. Spagnolo, P. Tenchini, R. Venturi, A. Verdini, P. G. Awunor, O. Blair, G. A. Cowan, G. Garcia-Bellido, A. Green, M. G. Medcalf, T. Misiejuk, A. Strong, J. A. Teixeira-Dias, P. Clifft, R. W. Edgecock, T. R. Norton, P. R. Tomalin, I. R. Ward, J. J. Bloch-Devaux, B. Boumediene, D. Colas, P. Fabbro, B. Lancon, E. Lemaire, M.-C. Locci, E. Perez, P. Rander, J. Tuchming, B. Vallage, B. Litke, A. M. Taylor, G. Booth, C. N. Cartwright, S. Combley, F. Hodgson, P. N. Lehto, M. Thompson, L. F. Bohrer, A. Brandt, S. Grupen, C. Hess, J. Ngac, A. Prange, G. Borean, C. Giannini, G. He, H. Putz, J. Rothberg, J. Armstrong, S. R. Berkelman, K. Cranmer, K. Ferguson, D. P. S. Gao, Y. Gonzalez, S. Hayes, O. J. Hu, H. Jin, S. Kile, J. McNamara, P. A., III Nielsen, J. Pan, Y. B. von Wimmersperg-Toeller, J. H. Wiedenmann, W. Wu, J. Wu, Sau Lan Wu, X. Zobernig, G. Dissertori, G. CA ALEPH Collaboration TI Measurement of the cross section for open b-quark production in two-photon interactions at LEP SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE e plus -e- experiments ID INCLUSIVE D-ASTERISK(+/-) PRODUCTION; PHOTON-PHOTON COLLISIONS; CARLO EVENT GENERATOR; MONTE-CARLO; DISCRIMINANT-ANALYSIS; JET PRODUCTION; DETECTOR; ALEPH; PHYSICS; SEARCH AB Inclusive b-quark production in two-photon collisions has been measured at LEP using an integrated luminosity of 698 pb(-1) collected by the ALEPH detector with root s between 130 and 209 GeV. The b quarks were identified using lifetime information. The cross section is found to be sigma(e(+)e -> e(+)e(-) bb(-)X) = (5.4 +/- 0.8(stat) +/- 0.8(syst)) pb, which is consistent with Next-to-Leading Order QCD. C1 Univ Barcelona, E-08208 Barcelona, Spain. Univ Montpellier 2, Grp Astroparticules Montpellier, F-34095 Montpellier, France. BNP Paribas, D-60325 Frankfurt, Germany. Univ Libre Bruxelles, Inst Inter Univ Hautes Energies, B-1050 Brussels, Belgium. Univ Palermo, Dipartimento Fis Tecnol Relative, Palermo, Italy. SLAC, Stanford, CA 94309 USA. CERN, CH-1211 Geneva 23, Switzerland. Univ Liverpool, Liverpool L697ZE, Merseyside, England. Polish Acad Sci, Henryk Niewodnicznski Inst Nucl Phys, Krakow, Poland. RP Schael, S (reprint author), Univ Barcelona, E-08208 Barcelona, Spain. RI Passalacqua, Luca/F-5127-2011; Focardi, Ettore/E-7376-2012; Bosman, Martine/J-9917-2014; Venturi, Andrea/J-1877-2012; Valassi, Andrea/K-7506-2012; Rolandi, Luigi (Gigi)/E-8563-2013; Colas, Paul/F-2876-2013; Ruiz, Hugo/H-4141-2013; Chmeissani, Mokhtar/G-4346-2015; Jones, Roger/H-5578-2011; Sguazzoni, Giacomo/J-4620-2015; O'Shea, Val/G-1279-2010; Fernandez, Enrique/L-5387-2014; Booth, Christopher/B-5263-2016; Casado, Pilar/H-1484-2015 OI Focardi, Ettore/0000-0002-3763-5267; Bosman, Martine/0000-0002-7290-643X; Valassi, Andrea/0000-0001-9322-9565; Rolandi, Luigi (Gigi)/0000-0002-0635-274X; Chmeissani, Mokhtar/0000-0002-2287-4791; Jones, Roger/0000-0002-6427-3513; Sguazzoni, Giacomo/0000-0002-0791-3350; O'Shea, Val/0000-0001-7183-1205; Fernandez, Enrique/0000-0002-6405-9488; Booth, Christopher/0000-0002-6051-2847; Casado, Pilar/0000-0002-0394-5646 NR 32 TC 3 Z9 3 U1 1 U2 10 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD SEP PY 2007 IS 9 AR 102 PG 20 WC Physics, Particles & Fields SC Physics GA 215DP UT WOS:000249788800027 ER PT J AU Pandrea, IV Gautam, R Ribeiro, RM Brenchley, JM Butler, IF Pattison, M Rasmussen, T Marx, PA Silvestri, G Lackner, AA Perelson, AS Douek, DC Veazey, RS Apetrei, C AF Pandrea, Ivona V. Gautam, Rajeev Ribeiro, Ruy M. Brenchley, Jason M. Butler, Isolde F. Pattison, Melissa Rasmussen, Terri Marx, Preston A. Silvestri, Guido Lackner, Andrew A. Perelson, Alan S. Douek, Daniel C. Veazey, Ronald S. Apetrei, Cristian TI Acute loss of intestinal CD4(+) T cells is not predictive of simian immunodeficiency virus virulence SO JOURNAL OF IMMUNOLOGY LA English DT Article ID AFRICAN-GREEN MONKEYS; IN-VIVO REPLICATION; HIV-1 INFECTION; VIRAL-LOAD; SIV INFECTION; GASTROINTESTINAL-TRACT; IMMUNE ACTIVATION; TYPE-1 INFECTION; RHESUS MACAQUE; MANDRILLUS-SPHINX AB The predictive value of acute gut-associated lymphoid tissue (GALT) CD4(+) T cell depletion in lentiviral infections was assessed by comparing three animal models illustrative of the outcomes of SIV infection: pathogenic infection (SIVsmm infection of rhesus macaques (Rh)), persistent nonprogressive infection (SIVagm infection of African green monkeys (AGM)), and transient, controlled infection (SIVagm infection of Rh). Massive acute depletion of GALT CD4(+) T cells was a common feature of acute SIV infection in all three models. The outcome of this mucosal CD4(+) T cell depletion, however, differed substantially between the three models: in SIVsmm-infected Rh, the acute GALT CD4(+) T cell depletion was persistent and continued with disease progression; in SIVagm, intestinal CD4(+) T cells were partially restored during chronic infection in the context of normal levels of apoptosis and immune activation and absence of damage to the mucosal immunologic barrier; in SIVagm-infected Rh, complete control of viral replication resulted in restoration of the mucosal barrier and immune restoration. Therefore, our data support a revised paradigm wherein severe GALT CD4(+) T cell depletion during acute pathogenic HIV and SIV infections of humans and Rh is necessary but neither sufficient nor predictive of disease progression, with levels of immune activation, proliferation and apoptosis being key factors involved in determining progression to AIDS. C1 Tulane Natl Primate Res Ctr, Covington, LA 70433 USA. Tulane Univ, Sch Publ Hlth, Dept Trop Med, New Orleans, LA 70112 USA. Tulane Univ, Sch Med, Dept Microbiol & Immunol, New Orleans, LA 70112 USA. Tulane Univ, Sch Med, Dept Pathol, New Orleans, LA 70112 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NIAID, Human Immunol Sect, Vaccine Res Ctr, NIH, Bethesda, MD 20892 USA. Univ Penn, Sch Med, Dept Pathol, Philadelphia, PA 19107 USA. RP Pandrea, IV (reprint author), Tulane Natl Primate Res Ctr, 18703 3 Rivers Rd, Covington, LA 70433 USA. EM ipandrea@tulanc.edu FU Intramural NIH HHS [Z99 AI999999, ZIA AI001029-02]; NCRR NIH HHS [P20 RR 020159, P20 RR020159, P51 RR 000164, P51 RR000164, R01 RR006555, RR 06555, RR 18745]; NIAID NIH HHS [AI 28433, R01 AI 064066, R01 AI 065325, R01 AI 49080, R01 AI028433, R01 AI049080, R01 AI064066, R01 AI065325, R21 AI 069935, R21 AI069935, R37 AI028433] NR 59 TC 164 Z9 164 U1 1 U2 6 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD SEP 1 PY 2007 VL 179 IS 5 BP 3035 EP 3046 PG 12 WC Immunology SC Immunology GA 203RN UT WOS:000248991800044 PM 17709518 ER PT J AU Hadley, GR AF Hadley, G. Ronald TI Slanted-wall beam propagation SO JOURNAL OF LIGHTWAVE TECHNOLOGY LA English DT Article DE beam propagation; diffractive optics; finite difference method ID OBLIQUE COORDINATE SYSTEM AB We present a new algorithm for wide-angle propagation through a general class of optical-waveguide structures defined by dielectric interfaces that may be slanted with respect to the direction of propagation. No regularity of the structure shapes is assumed, no coordinate transformations are employed, and the movement of each grid point between propagation steps is arbitrary within modest angular limitations. When used with an appropriate grid-generation algorithm, this method allows the modeling of an extremely wide variety of high-index-contrast waveguide structures, including meanders and tapers, with good phase accuracy and energy conservation. C1 Sandia Natl Labs, Albuquerque, NM 87131 USA. RP Hadley, GR (reprint author), Sandia Natl Labs, Albuquerque, NM 87131 USA. NR 13 TC 3 Z9 3 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0733-8724 J9 J LIGHTWAVE TECHNOL JI J. Lightwave Technol. PD SEP PY 2007 VL 25 IS 9 BP 2367 EP 2375 DI 10.1109/JLT.2007.901522 PG 9 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA 208WN UT WOS:000249350000011 ER PT J AU Qian, CQ Pines, A Martin, RW AF Qian, Chunqi Pines, Alex Martin, Rachel W. TI Design and construction of a contactless mobile RF coil for double resonance variable angle spinning NMR SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE liquid crystal NMR spectroscopy; variable angle spinning; NMR probe; resonator; capacitive coupling ID HIGH-RESOLUTION NMR; LIQUID-CRYSTALS; PROBE DESIGN; SOLIDS; FIELD; MAGNETISM AB Variable angle spinning (VAS) experiments can be used to measure long-range dipolar couplings and provide structural information about molecules in oriented media. We present a probe design for this type of experiment using a contactless resonator. In this circuit, RF power is transmitted wirelessly via coaxial capacitive coupling where the coupling efficiency is improved by replacing the ordinary sample coil with a double frequency resonator. Our probe constructed out of this design principle has shown favorable properties at variable angle conditions. Moreover, a switched angle spinning correlation experiment is performed to demonstrate the probe's capability to resolve dipolar couplings in strongly aligned molecules. (c) 2007 Elsevier Inc. All rights reserved. C1 Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Martin, RW (reprint author), Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. EM rwmartin@uci.edu RI Qian, Chunqi/A-7481-2012 NR 16 TC 8 Z9 8 U1 1 U2 10 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD SEP PY 2007 VL 188 IS 1 BP 183 EP 189 DI 10.1016/j.jmr.2007.06.006 PG 7 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 214PO UT WOS:000249750800020 PM 17638585 ER PT J AU Heyderman, LJ Czekaj, S Nolting, F Kim, DH Fischer, P AF Heyderman, L. J. Czekaj, S. Nolting, F. Kim, D.-H. Fischer, P. TI Cobalt antidot arrays on membranes: Fabrication and investigation with transmission X-ray microscopy SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT Joint European Magnetic Symposia (JEMS 06) CY JUN 26-29, 2006 CL San Sebastian, SPAIN SP Natl Advisory Comm ID PHOTOEMISSION ELECTRON-MICROSCOPY; MAGNETIC-PROPERTIES; STORAGE; FILM AB We have developed a method to fabricate ferromagnetic antidot arrays on silicon nitride membrane substrates for electron or soft X-ray microscopy with antidot periods ranging from 2 mu m down to 200 nm. Observations of cobalt antidot arrays with magnetic soft X-ray microscopy show that for large periods, flux closure states occur between the antidots in the as-grown state and on application of a magnetic field, domain chains are created which show a spin configuration at the chain ends comprising four 90 degrees walls. Pinning of the domain chain ends plays an important role in the magnetization reversal, determining the length of the chains and resulting in preservation of the domain chain configuration on reducing of the applied magnetic field to zero. (C) 2007 Elsevier B. V. All rights reserved. C1 Paul Scherrer Inst, CH-5232 Villigen, Switzerland. LBNL, CXRO, Berkeley, CA 94720 USA. RP Heyderman, LJ (reprint author), Paul Scherrer Inst, CH-5232 Villigen, Switzerland. EM laura.heyderman@psi.ch RI Fischer, Peter/A-3020-2010; Kim, Dong-Hyun/F-7195-2012; MSD, Nanomag/F-6438-2012; Heyderman, Laura/E-7959-2015 OI Fischer, Peter/0000-0002-9824-9343; NR 15 TC 9 Z9 9 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD SEP PY 2007 VL 316 IS 2 BP 99 EP 102 DI 10.1016/j.jmmm.2007.02.010 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 191RQ UT WOS:000248150000003 ER PT J AU Cambel, V Karapetrov, G Novosad, V Bartolome, E Gregusova, D Fedor, J Kudela, R Soltys, J AF Cambel, Vladimir Karapetrov, Goran Novosad, Valentyn Bartolome, Elena Gregusova, Dagmar Fedor, Jan Kudela, Robert Soltys, Jan TI Novel Hall sensors developed for magnetic field imaging systems SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT Joint European Magnetic Symposia (JEMS 06) CY JUN 26-29, 2006 CL San Sebastian, SPAIN SP Natl Advisory Comm DE Hall sensor; semiconductor heterostructure; magnetic domain structure; scanning hall probe microscopy; YBCO superconducting tape ID SUPERCONDUCTORS AB We report here on the fabrication and application of novel planar Hall sensors based on shallow InGaP/AlGaAs/GaAs heterostructure with a two-dimensional electron gas (2DEG) as an active layer. The sensors are developed for two kinds of experiments. In the first one, magnetic samples are placed directly on the Hall sensor. Room temperature experiments of permalloy objects evaporated onto the sensor are presented. In the second experiment, the sensor scans close over a multigranular superconducting sample prepared on a YBCO thin film. Large-area and high-resolution scanning experiments were performed at 4.2 K with the Hall probe scanning system in a liquid helium flow cryostat. (C) 2007 Elsevier B.V. All rights reserved. C1 Slovak Acad Sci, Inst Elect Engn, Bratislava 84104, Slovakia. Argonne Natl Lab, Argonne, IL USA. Univ Autonoma Barcelona, Dept Fis, Grp Electromagnetisme, Bellaterra 08193, Spain. RP Cambel, V (reprint author), Slovak Acad Sci, Inst Elect Engn, Dubravska Cesta 9, Bratislava 84104, Slovakia. EM Vladimir.Cambel@savba.sk RI Novosad, Valentyn/C-2018-2014; Novosad, V /J-4843-2015; Karapetrov, Goran/C-2840-2008 OI Karapetrov, Goran/0000-0003-1113-0137 NR 8 TC 3 Z9 3 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD SEP PY 2007 VL 316 IS 2 BP 232 EP 235 DI 10.1016/j.jmmm.2007.02.104 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 191RQ UT WOS:000248150000037 ER PT J AU Herrero-Albillos, J Garcia, LM Bartolome, F Young, AT Funk, T AF Herrero-Albillos, J. Garcia, L. M. Bartolome, F. Young, A. T. Funk, T. TI Experimental evidence of intrinsic Co magnetic moment in paramagnetic ErCo2 SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT Joint European Magnetic Symposia (JEMS 06) CY JUN 26-29, 2006 CL San Sebastian, SPAIN SP Natl Advisory Comm DE Laves phase; X-ray magnetic circular dichroism; paramagnetic susceptibility ID VISCOSITY AB Magnetic AC susceptibility (chi(AC)) has been measured as a function of the temperature and the excitation frequency (omega) in order to study the nature of the Co 3d magnetic moment in the paramagnetic phase of ErCo2. The chi(AC) measurements show a small feature near 100 K, both as a function of omega and temperature, associated with a relaxation process of intrinsic Co moments. The calculated Co magnetic moment from those measurements is around 0: 20 mu(B). This result has been con. cofirmed by means of X- ray magnetic circular dichroism measurements above and below the magnetic transition of ErCo2, yielding to an intrinsic Co moment of 0: 19 mu(B) in paramagnetic phase. (c) 2007 Elsevier B. V. All rights reserved. C1 Univ Zaragoza, CSIC, Inst Ciencia Mat Aragon, Dept Fis Mat Condensada, E-50009 Zaragoza, Spain. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Calif San Francisco, Phys Res Lab, San Francisco, CA 94107 USA. RP Herrero-Albillos, J (reprint author), Univ Zaragoza, CSIC, Inst Ciencia Mat Aragon, Dept Fis Mat Condensada, Pedro Cerbuna 12, E-50009 Zaragoza, Spain. EM Julia.Herrero@unizar.es RI Herrero-Albillos, Julia/B-9837-2009; Herrero-Albillos, Julia/I-5462-2012; Bartolome, Fernando/K-1700-2014 OI Herrero-Albillos, Julia/0000-0002-0901-8341; Herrero-Albillos, Julia/0000-0002-0901-8341; Bartolome, Fernando/0000-0002-0047-1772 NR 13 TC 7 Z9 7 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD SEP PY 2007 VL 316 IS 2 BP E442 EP E445 DI 10.1016/j.jmmm.2007.02.176 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 191RQ UT WOS:000248150000218 ER PT J AU Pena, V Visani, C Bruno, F Garcia-Barriocanal, J Arias, D Rivera, A Sefrioui, Z Leon, C Velthuis, SGET Hoffmann, A Nemes, N Garcia-Hernandez, M Martinez, JL Santamaria, J AF Pena, V. Visani, C. Bruno, F. Garcia-Barriocanal, J. Arias, D. Rivera, A. Sefrioui, Z. Leon, C. Velthuis, S. G. E. Te Hoffmann, A. Nemes, N. Garcia-Hernandez, M. Martinez, J. L. Santamaria, J. TI Magnetoresistance in La0.7Ca0.3MnO3-YBa2Cu3O7F/S/F trilayers SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT 3rd Joint European Magnetic Symposia (JEMS 06) CY JUN 26-29, 2006 CL San Sebastian, SPAIN SP Natl Advisory Comm DE magnetoresistance-multilayers; superconductivity-high T-c; multilayers-metallic ID LA0.7CA0.3MNO3/YBA2CU3O7-DELTA SUPERLATTICES; SUPERCONDUCTIVITY; MULTILAYERS AB We report large magnetoresistance in ferromagnet/superconductor/ferromagnet structures made of La0.7Ca0.3MnO3 and YBa2Cu3O7 at temperatures along the resistive transition. We find that the magnetoresistance phenomenon is independent on the orientation of electric current versus field. Furthermore, the effect is also independent on the sweep rate of the magnetic field. This excludes interpretations in terms of spontaneous vortices or anisotropic magnetoresistance of the ferromagnetic layers and supports the view that the magnetoresistance phenomenon originates at the spin-dependent transport of quasiparticles transmitted from the ferromagnetic electrodes into the superconductor. (c) 2007 Published by Elsevier B.V. C1 Univ Complutense Madrid, Dept Fis Aplicada 3, GFMC, E-28040 Madrid, Spain. CSIC, Inst Ciencia Mat Madrid, E-28049 Madrid, Spain. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Santamaria, J (reprint author), Univ Complutense Madrid, Dept Fis Aplicada 3, GFMC, E-28040 Madrid, Spain. EM jacsan@fis.ucm.es RI Bruno, Flavio/C-7380-2008; Hoffmann, Axel/A-8152-2009; Leon, Carlos/A-5587-2008; Nemes, Norbert Marcel/B-6275-2009; Martinez, Jose/B-5371-2013; te Velthuis, Suzanne/I-6735-2013; Garcia-Hernandez, Mar/J-9520-2014; Santamaria, Jacobo/N-8783-2016; Sefrioui, Zouhair/C-2728-2017 OI Bruno, Flavio/0000-0002-3970-8837; Hoffmann, Axel/0000-0002-1808-2767; Leon, Carlos/0000-0002-3262-1843; Nemes, Norbert Marcel/0000-0002-7856-3642; Martinez, Jose/0000-0001-9046-8237; te Velthuis, Suzanne/0000-0002-1023-8384; Garcia-Hernandez, Mar/0000-0002-5987-0647; Santamaria, Jacobo/0000-0003-4594-2686; Sefrioui, Zouhair/0000-0002-6703-3339 NR 18 TC 1 Z9 1 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD SEP PY 2007 VL 316 IS 2 BP E745 EP E748 DI 10.1016/j.jmmm.2007.03.082 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 191RQ UT WOS:000248150000301 ER PT J AU Spichkin, YI Derkach, AV Tishin, AM Kuz'min, MD Chernyshov, AS Gschneidner, KA Pecharsky, VK AF Spichkin, Y. I. Derkach, A. V. Tishin, A. M. Kuz'min, M. D. Chernyshov, A. S. Gschneidner, K. A., Jr. Pecharsky, V. K. TI Thermodynamic features of magnetization and magnetocaloric effect near the magnetic ordering temperature of Gd SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT Joint European Magnetic Symposia (JEMS 06) CY JUN 26-29, 2006 CL San Sebastian, SPAIN SP Natl Advisory Comm DE magnetocaloric effect; magnetic phase transition; magnetization ID GADOLINIUM; REFRIGERATION AB The magnetic field and temperature dependences of the adiabatic temperature change (Delta T) were measured in single-crystalline and polycrystalline gadolinium (Gd) near the Curie point (T(C)) by a direct method while continuously changing magnetic field (H) at different rates and the more conventional stepping of the magnetic field from 0 to 1.2 T. The Delta T(H) behavior has a tendency towards saturation at high magnetic fields, which is similar for both the polycrystal and the single crystal (in the latter case, the magnetic field vectors was parallel to the c-axis of the crystal). The Curie temperature of Gd was determined from Belov-Goryaga (Arrott) plots using isothermal magnetization data and a similar technique using adiabatic temperature change isotherms. In the latter case, T(C) was about 9 K higher than in the first case. Possible reasons for the observed difference are discussed. (C) 2007 Published by Elsevier B.V. C1 Adv Magnet Technol & Consulting Ltd, Moscow 117393, Russia. Moscow MV Lomonosov State Univ, Fac Phys, Moscow 119992, Russia. IFW Dresden, Leibniz Inst Festkorper & Werkstofforsch, D-01171 Dresden, Germany. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Spichkin, YI (reprint author), Adv Magnet Technol & Consulting Ltd, Moscow 117393, Russia. EM spichkin@NdFeB.ru RI Tishin, Alexander/E-8705-2014; OI Tishin, Alexander/0000-0003-2252-7279; Spichkin, Yury/0000-0002-6088-5395 NR 16 TC 19 Z9 19 U1 1 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD SEP PY 2007 VL 316 IS 2 BP E555 EP E557 DI 10.1016/j.jmmm.2007.03.017 PG 3 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 191RQ UT WOS:000248150000249 ER PT J AU Varga, T Moats, JL Ushakov, SV Navrotsky, A AF Varga, Tamas Moats, Julianna L. Ushakov, Sergey V. Navrotsky, Alexandra TI Thermochemistry of A(2)M(3)O(12) negative thermal expansion materials SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID HIGH-TEMPERATURE CALORIMETRY; EARTH ION CONDUCTION; HIGH-PRESSURE; SCANDIUM MOLYBDATE; PHASE-TRANSITIONS; VIBRATIONAL PROPERTIES; POWDER DIFFRACTION; SOLID-SOLUTION; AL-2(WO4)(3); AMORPHIZATION AB The enthalpies of the monoclinic to orthorhombic transition for a series of A(2)M(3)O(12) (A = Al, Cr, Fe, In, and Sc; M = Mo or W) compounds were measured by differential scanning calorimetry, and entropies of transition were estimated. The enthalpies of formation from the binary oxides at 25 degrees C for several A(2)M(3)O(12) samples were obtained from drop solution calorimetry in molten 3Na(2)O center dot 4MoO(3) at 702 degrees C. The monoclinic and orthorhombic phases Of Sc2Mo3O12 and Sc2W3O12 are the only phases that are enthalpically stable under ambient conditions. The enthalpies of formation from the oxides (Delta H-f,H-ox) for orthorhombic Sc2Mo3O12 and Sc2W3O12 are -47.2 +/- 2.1 kJ/mol and -8.5 +/- 2.7 kJ/mol, respectively. For Fe2Mo3O12, In2Mo3O12, and In2W3O12, Delta H-f,H-ox values are 51.5 +/- 4.5, 7.4 +/- 2.9, and 44.5 +/- 2.3 kJ/mol, respectively. These phases are entropically stabilized and/or metastable. Enthalpies of formation for phases that could not be measured by calorimetry have been estimated from the enthalpies of transition or trends in the enthalpies of formation. In general, the monoclinic phase is slightly enthalpically stabilized over the orthorhombic phase, while transition to the orthorhombic phase is entropically favored. This confirms that the orthorhombic phase is stable at high temperatures, the monoclinic is stable at low temperatures, and the monoclinic to orthorhombic transition is reversible. C1 Univ Calif Davis, Fac Nanomat Environm Agr & Technol Organ Res Unit, Thermochem Facil, Davis, CA 95616 USA. RP Varga, T (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM tvarga@anl.gov RI Ushakov, Sergey/C-5501-2008; Ushakov, Sergey/I-7278-2012; OI Ushakov, Sergey/0000-0002-8184-8884 NR 61 TC 17 Z9 17 U1 4 U2 15 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD SEP PY 2007 VL 22 IS 9 BP 2512 EP 2521 DI 10.1557/JMR.2007.0311 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 206GA UT WOS:000249170700023 ER PT J AU Reedy, ED AF Reedy, E. D., Jr. TI Contact mechanics for coated spheres that includes the transition from weak to strong adhesion SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID JKR-DMT TRANSITION; SPHERICAL INDENTER; HALF-SPACE; FRICTION AB Recently published results for a rigid spherical indenter contacting a thin, linear elastic coating on a rigid planar substrate have been extended to include the case of two contacting spheres, where each sphere is rigid and coated with a thin, linear elastic material. This is done by using an appropriately chosen effective radius and coating modulus. The earlier work has also been extended to provide analytical results that span the transition between the previously derived Derjaguin-Muller-Toporov (DMT)-like (work of adhesion/coating-modulus ratio is small) and Johnson-Kendall-Roberts (JKR)-like (work of adhesion/coating-modulus ratio is large) limits. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Reedy, ED (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM edreedy@sandia.gov NR 18 TC 12 Z9 12 U1 1 U2 7 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD SEP PY 2007 VL 22 IS 9 BP 2617 EP 2622 DI 10.1557/JMR.2007.0329 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 206GA UT WOS:000249170700036 ER PT J AU Song, B Chen, W Lu, WY AF Song, B. Chen, W. Lu, W.-Y. TI Compressive mechanical response of a low-density epoxy foam at various strain rates SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID POLYMERIC FOAMS; BEHAVIOR; WAVES AB We experimentally obtained compressive stress-strain response of a low-density epoxy foam at various strain rates. In particular, compressive stress-strain behavior at intermediate strain rates that has not been previously well understood were characterized by using a modified MTS and a split Hopkinson pressure bar (SHPB). Strain rate effects on the modulus of elasticity and cell-collapse stress for this low-density epoxy foam were determined. C1 Purdue Univ, Sch Aeronaut & Astronaut, W Lafayette, IN 47907 USA. Purdue Univ, Sch Mat Engn, W Lafayette, IN 47907 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Chen, W (reprint author), Purdue Univ, Sch Aeronaut & Astronaut, 315 N Grant St, W Lafayette, IN 47907 USA. EM songb@purdue.edu RI Song, Bo/D-3945-2011 NR 18 TC 15 Z9 19 U1 2 U2 14 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2461 EI 1573-4803 J9 J MATER SCI JI J. Mater. Sci. PD SEP PY 2007 VL 42 IS 17 BP 7502 EP 7507 DI 10.1007/s10853-007-1612-z PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 188QQ UT WOS:000247934800064 ER PT J AU Christensen, RM AF Christensen, Richard M. TI A comparison of open cell and closed cell properties for low-density materials SO JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES LA English DT Article DE low density materials; open cell; closed cell ID COMPRESSIVE RESPONSE; ELASTIC PROPERTIES; FOAMS; MODELS AB The stiffness and strength properties for open cell and closed cell low-density materials are collected and compared. These are the theoretical predictions for the Kelvin cell type and the oct-tet cell type of open cell forms and of the closed cell form from the generalized self-consistent method. The strength properties considered are those for plastic collapse and elastic instability, under both uniaxial stress and dilatational stress conditions. C1 [Christensen, Richard M.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. [Christensen, Richard M.] Stanford Univ, Dept Aeronaut & Astronaut, Stanford, CA 94305 USA. RP Christensen, RM (reprint author), Lawrence Livermore Natl Lab, POB 808,L-356, Livermore, CA 94550 USA. EM christensen6@llnl.gov NR 14 TC 2 Z9 2 U1 0 U2 4 PU MATHEMATICAL SCIENCE PUBL PI BERKELEY PA UNIV CALIFORNIA, DEPT MATHEMATICS, BERKELEY, CA 94720-3840 USA SN 1559-3959 J9 J MECH MATER STRUCT JI J. Mech. Mater. Struct. PD SEP PY 2007 VL 2 IS 7 BP 1299 EP 1307 DI 10.2140/jomms.2007.2.1299 PG 9 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA 308RC UT WOS:000256406700007 ER PT J AU Morse, JD Upadhye, RS Graff, RT Spadaccini, C Park, HG Hart, EK AF Morse, J. D. Upadhye, R. S. Graff, R. T. Spadaccini, C. Park, H. G. Hart, E. K. TI A MEMS-based reformed methanol fuel cell for portable power SO JOURNAL OF MICROMECHANICS AND MICROENGINEERING LA English DT Article; Proceedings Paper CT 6th International Workshop on Micro and Nanotechnologies for Power Generation and Energy Conversion Applications CY 2006 CL Berkeley, CA ID PROTON-EXCHANGE MEMBRANE; PERFORMANCE; FABRICATION; ELECTRODES; SILICON; DESIGN AB A reformed methanol fuel cell system is described. The use of a microfluidic fuel processor enables component scaling and integration sufficient to achieve power sources in the 2-10 W regime that are competitive in size and energy density in comparison to alternative power sources. While carbon monoxide tolerance of proton conducting membranes has typically limited the performance of reformed methanol fuel cells, phosphoric-acid-doped polybenzimidazole (PBI) membranes have been tested that exhibit no degradation for carbon monoxide > 2% mole fraction. Further benefits of the PBI membrane include operating temperature of 150-200 degrees C, and no need for water to assist protonic conduction. As a result, a chemically and thermally robust fuel cell power source is realized. Results of methanol steam reforming and catalytic combustor heating elements formed in a silicon MEMS platform, and PBI membrane performance with reformate fuel feed will be discussed. C1 Lawrence Livermore Natl Lab, Ctr Meso Micro & Nano Technol, Livermore, CA 94550 USA. Stanford Univ, Dept Mat Sci, Stanford, CA 94305 USA. RP Morse, JD (reprint author), Lawrence Livermore Natl Lab, Ctr Meso Micro & Nano Technol, 7000 E Ave, Livermore, CA 94550 USA. EM morse3@llnl.gov RI Park, Hyung Gyu/F-3056-2013 OI Park, Hyung Gyu/0000-0001-8121-2344 NR 19 TC 11 Z9 11 U1 0 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0960-1317 J9 J MICROMECH MICROENG JI J. Micromech. Microeng. PD SEP PY 2007 VL 17 IS 9 BP S237 EP S242 DI 10.1088/0960-1317/17/9/S05 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Instruments & Instrumentation; Physics, Applied SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation; Physics GA 206ZW UT WOS:000249222400006 ER PT J AU Peterson, RB Paul, BK Palmer, T Wu, Q Jost, W Tseng, CHT Tiwari, S Patello, G Buck, EC Holladay, JD Shimskey, R Humble, P MacFarlan, P Wainright, J AF Peterson, Richard B. Paul, Brian K. Palmer, Todd Wu, Qiao Jost, William Tseng, Chih-Heng T. Tiwari, Santosh Patello, Gertrude Buck, Edgar C. Holladay, Jamelyn D. Shimskey, Rick Humble, Paul MacFarlan, Paul Wainright, Jesse TI Radiolytic microscale power generation based on single chamber fuel cell operation SO JOURNAL OF MICROMECHANICS AND MICROENGINEERING LA English DT Article; Proceedings Paper CT 6th International Workshop on Micro and Nanotechnologies for Power Generation and Energy Conversion Applications CY 2006 CL Berkeley, CA AB Proof-of-principle test results are presented for a nuclear-to-electric power generation technique utilizing closed-cycle fuel cell operation. The approach being developed is to first use the decay energy of a radioisotope to generate H-2 and O-2 from water, and then to utilize these species in a fuel cell to generate electricity. The principle of operation allows the device to regenerate its own reactants and operate continuously as a closed system for as long as the primary source of power, namely the radioisotope, is active. With micro engineering and fabrication techniques available today, a miniaturized integrated package of 1 cm(3) in size and producing power in the 10 mW range appears feasible in a mature design. Smaller devices producing less power would also be possible. For this project, a unique fuel cell capable of utilizing mixed reactants at room temperature has been developed. The efficiency of this early fuel cell design falls in the range between 10 and 20%. Measured power output from a radioisotope fueled test cell approached 0.45 mW for several hours with a radiation leakage rate estimated at 490 mrem yr(-1). C1 Oregon State Univ, Dept Mech Engn, Corvallis, OR 97331 USA. Oregon State Univ, Dept Ind & Mfg Engn, Corvallis, OR 97331 USA. Oregon State Univ, Dept Nucl Engn, Corvallis, OR 97331 USA. Battelle Pacific NW Div, Richland, WA USA. Case Western Reserve Univ, Cleveland, OH USA. RP Peterson, RB (reprint author), Oregon State Univ, Dept Mech Engn, Corvallis, OR 97331 USA. EM richard.peterson@oregonstate.edu RI Buck, Edgar/D-4288-2009; Humble, Paul/K-1961-2012; Buck, Edgar/N-7820-2013; Humble, Paul/E-4766-2015 OI Humble, Paul/0000-0002-2632-6557; Buck, Edgar/0000-0001-5101-9084; NR 15 TC 3 Z9 3 U1 1 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0960-1317 J9 J MICROMECH MICROENG JI J. Micromech. Microeng. PD SEP PY 2007 VL 17 IS 9 BP S250 EP S256 DI 10.1088/0960-1317/17/9/S07 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Instruments & Instrumentation; Physics, Applied SC Engineering; Science & Technology - Other Topics; Instruments & Instrumentation; Physics GA 206ZW UT WOS:000249222400008 ER PT J AU Frank, JH Elder, AD Swartling, J Venkitaraman, AR Jeyasekharan, AD Kaminski, CF AF Frank, J. H. Elder, A. D. Swartling, J. Venkitaraman, A. R. Jeyasekharan, A. D. Kaminski, C. F. TI A white light confocal microscope for spectrally resolved multidimensional imaging SO JOURNAL OF MICROSCOPY LA English DT Article DE confocal microscopy; fluorescence microscopy; photonic crystal fibre; supercontinuum ID PHOTONIC CRYSTAL FIBER; FLUORESCENCE MICROSCOPY; MULTIPHOTON MICROSCOPY; LASER SOURCE; EXCITATION; COLOCALIZATION; SPECTROSCOPY; PROTEINS; COLOR AB Spectrofluorometric imaging microscopy is demonstrated in a confocal microscope using a supercontinuum laser as an excitation source and a custom-built prism spectrometer for detection. This microscope system provides confocal imaging with spectrally resolved fluorescence excitation and detection from 450 to 700 nm. The supercontinuum laser provides a broad spectrum light source and is coupled with an acousto-optic tunable filter to provide continuously tunable fluorescence excitation with a 1-nm bandwidth. Eight different excitation wavelengths can be simultaneously selected. The prism spectrometer provides spectrally resolved detection with sensitivity comparable to a standard confocal system. This new microscope system enables optimal access to a multitude of fluorophores and provides fluorescence excitation and emission spectra for each location in a 3D confocal image. The speed of the spectral scans is suitable for spectrofluorometric imaging of live cells. Effects of chromatic aberration are modest and do not significantly limit the spatial resolution of the confocal measurements. C1 Sandia Natl Labs, Combust Res Facil, Oakland, CA 94611 USA. Univ Cambridge, Dept Chem Engn, Cambridge CB2 3RA, England. Hutchinson MRC, Res Ctr, MRC Canc Cell Unit, Cambridge, England. RP Frank, JH (reprint author), Sandia Natl Labs, Combust Res Facil, Oakland, CA 94611 USA. EM jhfrank@sandia.gov; cfk23@cam.ac.uk RI Kaminski, Clemens/G-7488-2016 FU Medical Research Council [G0600332, G0700651, G9900064, MC_U105359877] NR 34 TC 55 Z9 57 U1 2 U2 15 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0022-2720 EI 1365-2818 J9 J MICROSC-OXFORD JI J. Microsc.. PD SEP PY 2007 VL 227 IS 3 BP 203 EP 215 DI 10.1111/j.1365-2818.2007.01803.x PG 13 WC Microscopy SC Microscopy GA 210JD UT WOS:000249451600002 PM 17760615 ER PT J AU Carpenter, DA Pugh, JL Richardson, GD Mooney, LR AF Carpenter, D. A. Pugh, J. L. Richardson, G. D. Mooney, L. R. TI Determination of pattern centre in EBSD using the moving-screen technique SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article DE calibration; electron backscatter diffraction; moving-screen technique; scanning electron microscopy AB The 'moving-screen' or 'pattern magnification' method of calibration for electron backscatter diffraction (EBSD) was reformulated to develop a high-precision technique requiring no crystallographic knowledge of the specimen and no initial estimates of the calibration parameters. The technique depends upon the accurate displacement of the screen and camera assembly. Corresponding points are selected, interactively, from EBSD patterns. It is suggested that, as an alternative, the selection of points from the Hough transform could lead to a completely automated routine. C1 Technol Dev Org, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Carpenter, DA (reprint author), Technol Dev Org, Y-12 Natl Secur Complex, Oak Ridge, TN 37831 USA. EM carpenterda@y12.doe.gov NR 6 TC 9 Z9 9 U1 0 U2 3 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD SEP PY 2007 VL 227 IS 3 BP 246 EP 247 DI 10.1111/j.1365-2818.2007.01807.x PG 2 WC Microscopy SC Microscopy GA 210JD UT WOS:000249451600006 PM 17760619 ER PT J AU Blackledge, CW Szarko, JM Dupont, A Chan, GH Read, EL Leone, SR AF Blackledge, Charles W. Szarko, Jodi M. Dupont, Aurelie Chan, George H. Read, Elizabeth L. Leone, Stephen R. TI Zinc oxide nanorod growth on gold islands prepared by microsphere lithography on silicon and quartz SO JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY LA English DT Article DE ZnO nanorods; gold islands; microsphere lithography patterning ID PATTERNED GROWTH; ZNO NANOWIRES; ARRAYS; NANOSTRUCTURES; TRANSPORT; EMISSION AB Gold islands, vapor deposited on silicon and quartz by microsphere lithography patterning, are used to nucleate arrays of ZnO nanorods. ZnO is grown on similar to 0.32 mu m(2) Au islands by carbothermal reduction in a tube furnace. Scanning electron microscopy (SEM) and energy dispersive atomic X-ray spectroscopy (EDS) confirm that the gold effectively controls the sites of nucleation of ZnO. Atomic force microscopy (AFM) shows that similar to 30 nm diameter nanorods grow horizontally, along the surface. Alloy droplets that are characteristic of the vapor-liquid-solid (VLS) mechanism are observed at the tips of the nanorods. The spatial growth direction of VLS catalyzed ZnO nanorods is along the substrate when they nucleate from gold islands on silicon and quartz. The energy of adhesion of the VLS droplet to the surface can account for the horizontal growth. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem & Phys, Berkeley, CA 94720 USA. Univ Colorado, Dept Chem & Biochem, JILA, Boulder, CO 80309 USA. RP Blackledge, CW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem & Phys, Berkeley, CA 94720 USA. OI Szarko, Jodi/0000-0002-2181-9408 NR 22 TC 5 Z9 5 U1 0 U2 11 PU AMER SCIENTIFIC PUBLISHERS PI STEVENSON RANCH PA 25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA SN 1533-4880 J9 J NANOSCI NANOTECHNO JI J. Nanosci. Nanotechnol. PD SEP PY 2007 VL 7 IS 9 BP 3336 EP 3339 DI 10.1166/jnn.2007.652 PG 4 WC Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 223QW UT WOS:000250388400046 PM 18019171 ER PT J AU Suzuki, Y Nankawa, T Ozaki, T Ohnuki, T Francis, AJ Enokida, Y Yamamoto, I AF Suzuki, Yoshinori Nankawa, Takuya Ozaki, Takuo Ohnuki, Toshihiko Francis, Arokiasarny J. Enokida, Youichi Yamamoto, Ichiro TI Electrochemical studies on uranium in the presence of organic acids SO JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY LA English DT Article DE uranium organic complex; organic acid; redox reaction; electrochemistry; cyclic voltammetry; stability constant; uranium(V); disproportionation ID PLUTONIUM; CHEMISTRY; MECHANISM AB We examined electrochemical redox reactions of UO22+ in perchlorate and organic acid (oxalic, malonic, succinic, adipic, L-malic, and L-tartaric acids) solutions using cyclic voltammetry to reveal the effects of complex formation with organic acids on the redox behavior. In the perchlorate and organic acid solutions, a redox reaction of UO22+/UO2+ and an oxidation reaction of U(TV) produced by a disproportionation Of UO2+ were observed. The peak potentials of the UO22+ reduction showed a good linear relationship with the stability constants of 1:1 UO22+-organic complexes. In the presence of malonic acid, the redox potential for UO22+/UO2+ was constant at pH 1-2 and 5-6 while it decreased with an increase in pH from 2 to 5. Additionally, it was independent of inalonate concentration at 0.1-0.5 M while it decreased with an increase in the concentration from 0.005 to 0.1 M. Based on the experimental and the speciation calculation results, we determined the redox reactions Of UO22+-malonate complexes as a function of pH and malonate concentration. We also determined the redox reactions Of UO22+-oxalate complexes in the same way. C1 Nagoya Univ, Grad Sch Engn, Dept Mat Phys & Energy Engn, Chikusa Ku, Nagoya, Aichi 4648603, Japan. Japan Atom Energy Agcy, Adv Sci Res Ctr, Tokai, Ibaraki 3191195, Japan. Nagoya Univ, EcoTopia Sci Inst, Chikusa Ku, Nagoya, Aichi 4648603, Japan. Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. RP Suzuki, Y (reprint author), Nagoya Univ, Grad Sch Engn, Dept Mat Phys & Energy Engn, Chikusa Ku, Furo Cho, Nagoya, Aichi 4648603, Japan. EM suzuki.yoshinori@jaea.go.jp RI Yamamoto, Ichiro/I-4226-2012 NR 20 TC 6 Z9 6 U1 3 U2 22 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0022-3131 EI 1881-1248 J9 J NUCL SCI TECHNOL JI J. Nucl. Sci. Technol. PD SEP PY 2007 VL 44 IS 9 BP 1227 EP 1232 DI 10.3327/jnst.44.1227 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 230NF UT WOS:000250882500011 ER PT J AU Guven, K Cakmak, AO Caliskan, MD Gundogdu, TF Kafesaki, M Soukoulis, CM Ozbay, E AF Guven, K. Cakmak, A. O. Caliskan, M. D. Gundogdu, T. F. Kafesaki, M. Soukoulis, C. M. Ozbay, E. TI Bilayer metamaterial: analysis of left-handed transmission and retrieval of effective medium parameters SO JOURNAL OF OPTICS A-PURE AND APPLIED OPTICS LA English DT Article; Proceedings Paper CT 1st European Topical Meeting on Nanophotonics and Metamaterials CY JAN 08-11, 2007 CL Seefeld, AUSTRIA DE metamaterial; negative index; split-ring resonator; negative refraction ID NEGATIVE-INDEX; OPTICAL METAMATERIALS; WIRE PAIRS; REFRACTION AB We report an experimental and numerical analysis of a planar metamaterial designed for normal-to-plane propagation, and operating at microwave frequencies. The metamaterial consists of cutwire and wire patterns, which are arranged periodically on both sides of a dielectric layer, in the form of a bilayer. The left-handed transmission band of the metamaterial is demonstrated experimentally. The effective index of refraction retrieved from the S parameters is found to be negative within this transmission band. An independent negative refraction experiment supports the existence of the negative index of refraction for the metamaterial. C1 Bilkent Univ, Nanotechnol Res Ctr, TR-06800 Ankara, Turkey. Bilkent Univ, Dept Phys, TR-06800 Ankara, Turkey. Bilkent Univ, Dept Elect & Elect Engn, TR-06800 Ankara, Turkey. Fdn Res & Technol Hellas FORTH, GR-71110 Iraklion, Greece. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Guven, K (reprint author), Bilkent Univ, Nanotechnol Res Ctr, TR-06800 Ankara, Turkey. RI Soukoulis, Costas/A-5295-2008; Ozbay, Ekmel/B-9495-2008; Kafesaki, Maria/E-6843-2012 OI Kafesaki, Maria/0000-0002-9524-2576 NR 23 TC 9 Z9 9 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1464-4258 J9 J OPT A-PURE APPL OP JI J. Opt. A-Pure Appl. Opt. PD SEP PY 2007 VL 9 IS 9 SI SI BP S361 EP S365 DI 10.1088/1464-4258/9/9/S13 PG 5 WC Optics SC Optics GA 203CW UT WOS:000248953700014 ER PT J AU Ji, H Sakellariou, G Advincula, RC Smith, GD Kilbey, SM Dadmun, MD Mays, JW AF Ji, Haining Sakellariou, Georgios Advincula, Rigoberto C. Smith, Grant D. Kilbey, S. Michael, II Dadmun, Mark D. Mays, Jimmy W. TI Synthesis and characterization of well-defined [polystyrene-b-poly(2-vinylpyridine)]n star-block copolymers with poly(2-vinylpyridine) corona blocks SO JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY LA English DT Article DE anionic polymerization; block copolymers; divinylbenzene; polystyrene-b-poly(2-vinylpyridine); star polymers ID LIVING ANIONIC-POLYMERIZATION; DILUTE-SOLUTION PROPERTIES; MULTIBLOCK COPOLYMERS; POLYMERS; BRUSHES; COMPATIBILIZATION; ARCHITECTURE; POLYSTYRENE; BLENDS AB This article describes the synthesis and characterization of [polystyreneb-poly(2-vinylpyridine)](n) star-block copolymers with the poly(2-vinylpyridine) blocks at the periphery. A two-step living anionic polymerization method was used. Firstly, oligo(styryl)lithium grafted poly(divinylbenzene) cores were used as multifunctional initiators to initiate living anionic polymerization of styrene in benzene at room temperature. Secondly, vinylpyridine was polymerized at the periphery of these living (polystyrene), stars in tetrahydrofuran at -78 degrees C. The resulting copolymers were characterized using size exclusion chromatography, multiangle laser light scattering, H-1 NMR, elemental analysis, and intrinsic viscosity measurements. (C) 2007 Wiley Periodicals, Inc. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Houston, Dept Chem, Houston, TX 77204 USA. Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. Univ Utah, Dept Chem & Fuel Engn, Salt Lake City, UT 84112 USA. Clemson Univ, Dept Chem Engn, Clemson, SC 29634 USA. Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Ctr Nanophase Mat Sci, Oak Ridge, TN 37831 USA. RP Mays, JW (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. EM jimmymays@utk.edu RI Sakellariou, Georgios/B-1752-2014 NR 27 TC 4 Z9 4 U1 2 U2 12 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-624X J9 J POLYM SCI POL CHEM JI J. Polym. Sci. Pol. Chem. PD SEP 1 PY 2007 VL 45 IS 17 BP 3949 EP 3955 DI 10.1002/pola.22148 PG 7 WC Polymer Science SC Polymer Science GA 208IL UT WOS:000249312900016 ER PT J AU Braud, AM Gonthier, KA Decroix, ME AF Braud, Adam M. Gonthier, Keith A. Decroix, Michele E. TI System Modeling of explosively actuated valves SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID PERFORMANCE; MICROTHRUSTERS; PREDICTION; DESIGN AB A model is formulated to describe time-dependent operation of an explosively actuated valve. The model accounts for burning of solid explosive to form product gas within an actuator, transport of product gas from the actuator to an expansion chamber, and insertion of an initially tapered piston into a constant diameter bore by gas pressure within the expansion chamber. A cutter attached to the piston punctures a diaphragm enabling the desired gas flow. An important model feature is the coupling of combustion energy to piston-housing deformation resulting from gas pressure and geometric interference during piston insertion. The model is correlated with quasi-static compression tests, and combustion bomb data for the explosive HMX (C4H8N3O8), that provide estimates for the valve work requirements, and the pressure dependent burning rate, respectively. The model is then used to predict operation of a baseline valve configuration and to assess how variations in explosive mass and valve geometry affect performance. Predictions indicate that 150 mg of HMX routinely used with the baseline valve induces far greater piston kinetic energy than needed for successful operation. The appropriateness of key assumptions about stress and deformation fields within the piston and housing are examined based on a rate-independent; finite-element analysis. C1 Louisiana State Univ, Dept Mech Engn, Baton Rouge, LA 70803 USA. Los Alamos Natl Lab, Decis Applicat Div, Los Alamos, NM 87545 USA. RP Gonthier, KA (reprint author), Louisiana State Univ, Dept Mech Engn, Baton Rouge, LA 70803 USA. EM gonthier@me.lsu.edu NR 21 TC 4 Z9 4 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD SEP-OCT PY 2007 VL 23 IS 5 BP 1080 EP 1095 DI 10.2514/1.27414 PG 16 WC Engineering, Aerospace SC Engineering GA 213MH UT WOS:000249671200023 ER PT J AU Anderson, GA Tolic, N Tang, XT Zheng, CX Bruce, JE AF Anderson, Gordon A. Tolic, Nikola Tang, Xiaoting Zheng, Chunxiang Bruce, James E. TI Informatics strategies for large-scale novel cross-linking analysis SO JOURNAL OF PROTEOME RESEARCH LA English DT Article ID TANDEM MASS-SPECTROMETRY; PROTEIN-PROTEIN INTERACTIONS; IDENTIFICATION; DISSOCIATION; DATABASES; SPECTRA; POLYPEPTIDE; PROTEOMICS; LINKERS; REVERSE AB The detection of protein interactions in biological systems represents a significant challenge for today's technology. Chemical cross-linking provides the potential to impart new chemical bonds in a complex system that result in mass changes in a set of tryptic peptides detected by mass spectrometry. However, system complexity and cross-linking product heterogeneity have precluded widespread chemical cross-linking use for large-scale identification of protein-protein interactions. The development of mass spectrometry identifiable cross-linkers called protein interaction reporters (PIRs) has enabled on-cell chemical cross-linking experiments with product type differentiation. However, the complex datasets resultant from PIR experiments demand new informatics capabilities to allow interpretation. This manuscript details our efforts to develop such capabilities and describes the program X-links, which allows PIR product type differentiation. Furthermore, we also present the results from Monte Carlo simulation of PIR-type experiments to provide false discovery rate estimates for the PIR product type identification through observed precursor and released peptide masses. Our simulations also provide peptide identification calculations based on accurate masses and database complexity that can provide an estimation of false discovery rates for peptide identification. Overall, the calculations show a low rate of false discovery of PIR product types due to random mass matching of approximately 12% with 10 ppm mass measurement accuracy and spectral complexity resulting from 100 peptides. In addition, consideration of a reduced database resulting from stage 1 analysis of Shewanella oneidensis MR-1 containing 367 proteins resulted in a significant reduction of expected identification false discovery rate estimation compared to that from the entire Shewanella oneidensis MR-1 proteome. C1 Washington State Univ, Dept Chem, Pullman, WA 99164 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Bruce, JE (reprint author), Washington State Univ, Dept Chem, Pullman, WA 99164 USA. EM james_bruce@wsu.edu FU NCRR NIH HHS [R01 RR023334, R01 RR023334-01A1, S10 RR022538, S10 RR022538-01] NR 33 TC 32 Z9 33 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1535-3893 J9 J PROTEOME RES JI J. Proteome Res. PD SEP PY 2007 VL 6 IS 9 BP 3412 EP 3421 DI 10.1021/pr070035z PG 10 WC Biochemical Research Methods SC Biochemistry & Molecular Biology GA 209EE UT WOS:000249371000007 PM 17676784 ER PT J AU Jang, DL Guo, MQ Wang, DJ AF Jang, Deok-Lin Guo, Mingquan Wang, Daojing TI Proteomic and biochemical studies of calcium- and phosphorylation-dependent calmodulin complexes in mammalian cells SO JOURNAL OF PROTEOME RESEARCH LA English DT Article DE calmodulin; protein complexes; calcium-dependent; phosphorylation-dependent; inositol 1,4,5-triphosphate receptor type 1 (IP(3)R1); DEAD box protein 3 (DDX3); DEAD box protein 5 (DDX5); ubiquitin-protein ligase EDD1; phosphatase PP1; phosphorylation site ID INOSITOL 1,4,5-TRISPHOSPHATE RECEPTOR; PROTEIN-KINASE-C; RECONSTITUTED LIPID VESICLES; TYROSINE PHOSPHORYLATION; MASS-SPECTROMETRY; TRISPHOSPHATE RECEPTOR; BINDING DOMAIN; RNA HELICASE; IP3 RECEPTOR; CANCER-CELLS AB Protein conformational changes due to cofactor binding (e.g., metal ions, heme) and/or post-translational modifications (e.g., phosphorylation) modulate dynamic protein complexes. Calmodulin (CaM) plays an essential role in regulating calcium signaling and homeostasis. Herein, we report a straightforward and systematic approach to identify potential calcium- and phosphorylation-dependent CaM complexes in a proteome-wide manner. We have identified over 120 CaM-associated proteins encompassing four different classes of CaM binding in HeLa cells, namely, calcium-dependent and phosphorylation-dependent (e.g., EDD1), calcium-dependent and phosphorylation-independent (e.g., myosin IE), calcium-independent and phosphorylation-dependent (e.g., DDX3), and calcium-independent and phosphorylation-independent (e.g., DDX5). To demonstrate the utility of our method in understanding biological pathways, we showed that in vivo phosphorylation of inositol 1,4,5-triphosphate receptor type 1 (IP3-R1) at Ser1598 significantly reduced the affinity of its Ca2+-dependent CaM binding. However, phosphorylation of IP(3)R1 did not substantially affect its Ca2+-independent CaM binding. These results shed new lights on the mechanism underlying the marked increase of Ca2+ release due to IP(3)R1 phosphorylation. We further showed that staurosporine-sensitive kinase(s) and phosphatase PP1 play a critical role in modulating the phosphorylation-dependent CaM binding of IP(3)R1. Our method may serve as a general strategy to identify and characterize phosphorylation-dependent protein complexes, to pinpoint the phosphorylation sites and associated kinase(s) and phosphatase(s) involved in the protein-protein interactions, and to functionally characterize these complexes in mammalian cells. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Wang, DJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM djwang@lbl.gov NR 60 TC 11 Z9 11 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1535-3893 J9 J PROTEOME RES JI J. Proteome Res. PD SEP PY 2007 VL 6 IS 9 BP 3718 EP 3728 DI 10.1021/pr0703268 PG 11 WC Biochemical Research Methods SC Biochemistry & Molecular Biology GA 209EE UT WOS:000249371000036 PM 17696464 ER PT J AU Sharp, JL Anderson, KK Hurst, GB Daly, DS Pelletier, DA Cannon, WR Auberry, DL Schmoyer, DD McDonald, WH White, AM Hooker, BS Victry, KD Buchanan, MV Kery, V Wiley, HS AF Sharp, Julia L. Anderson, Kevin K. Hurst, Gregory B. Daly, Don S. Pelletier, Dale A. Cannon, William R. Auberry, Deanna L. Schmoyer, Denise D. McDonald, W. Hayes White, Amanda M. Hooker, Brian S. Victry, Kristin D. Buchanan, Michelle V. Kery, Vladimir Wiley, H. Steven TI Statistically inferring protein-protein associations with affinity isolation LC-MS/MS assays SO JOURNAL OF PROTEOME RESEARCH LA English DT Article DE protein-protein interaction; affinity isolation; LC-MS/MS; likelihood ratio test; Bayes' odds ID TANDEM MASS-SPECTROMETRY; ESCHERICHIA-COLI; SACCHAROMYCES-CEREVISIAE; DATA SETS; COMPLEXES; IDENTIFICATION; HOLOENZYME; PROTEOMICS; FRAMEWORK; DNA AB Affinity isolation of protein complexes followed by protein identification by LC-MS/MS is an increasingly popular approach for mapping protein interactions. However, systematic and random assay errors from multiple sources must be considered to confidently infer authentic protein-protein interactions. To address this issue, we developed a general, robust statistical method for inferring authentic interactions from protein prey-by-bait frequency tables using a binomial-based likelihood ratio test (LRT) coupled with Bayes' Odds estimation. We then applied our LRT-Bayes' algorithm experimentally using data from protein complexes isolated from Rhodopseudomonas palustris. Our algorithm, in conjunction with the experimental protocol, inferred with high confidence authentic interacting proteins from abundant, stable complexes, but few or no authentic interactions for lower-abundance complexes. The algorithm can discriminate against a background of prey proteins that are detected in association with a large number of baits as an artifact of the measurement. We conclude that the experimental protocol including the LRT-Bayes' algorithm produces results with high confidence but moderate sensitivity. We also found that Monte Carlo simulation is a feasible tool for checking modeling assumptions, estimating parameters, and evaluating the significance of results in protein association studies. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37837 USA. Clemson Univ, Clemson, SC 29634 USA. RP Sharp, JL (reprint author), Montana State Univ, Bozeman, MT 59717 USA. EM julia.1.sharp@gmail.com RI Pelletier, Dale/F-4154-2011; Cannon, William/K-8411-2014; McDonald, W. Hayes/B-4109-2016; OI Cannon, William/0000-0003-3789-7889; McDonald, W. Hayes/0000-0002-3510-426X; Anderson, Kevin/0000-0001-5613-5893; Hurst, Gregory/0000-0002-7650-8009; Wiley, Steven/0000-0003-0232-6867; Hooker, Brian/0000-0003-2010-1899 NR 30 TC 8 Z9 9 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1535-3893 J9 J PROTEOME RES JI J. Proteome Res. PD SEP PY 2007 VL 6 IS 9 BP 3788 EP 3795 DI 10.1021/pr0701106 PG 8 WC Biochemical Research Methods SC Biochemistry & Molecular Biology GA 209EE UT WOS:000249371000043 PM 17691832 ER PT J AU Snyder, SC Lassahn, GD Grandy, JD AF Snyder, S. C. Lassahn, G. D. Grandy, J. D. TI Direct determination of gas velocity and gas temperature in an atmospheric-pressure argon-hydrogen plasma jet SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE Thomson scattering; laser diagnostics of plasmas; plasma diagnostics; thermal plasma jets ID LASER-LIGHT SCATTERING; FREE-BURNING ARC; THOMSON; PROFILES; DENSITY AB Direct gas temperature and gas velocity measurements made in the exit plane of a subsonic argon-hydrogen thermal plasma jet from high-resolution lineshape analysis of laser light scattered by the plasma are reported. The lineshapes are in general a superposition of the ion feature of the Thomson-scattered light and the lineshape of Rayleigh scattered light. In the center of the jet Thomson scattering dominates while at larger radii Rayleigh scattering dominates. Because of the complexity of the lineshapes of light scattered by multicomponent plasmas, only those that are predominantly due to Thomson scattering can in practice be analyzed for gas temperature. Gas velocity can be determined from the Doppler shift of the lineshapes relative to the frequency of the incident laser if the velocity is greater than about 50 m s(-1). The maximum gas temperature measured was 14,500 K +/- 5%. The maximum gas velocity measured was 1100 m s(-1) +/- 3%. Temperature values and the radial velocity profile are compared with those previously obtained from a subsonic all-argon plasma jet operated under similar conditions. (c) 2007 Elsevier Ltd. All rights reserved. C1 Montana State Univ, Dept Biol & Phys Sci, Billings, MT 59101 USA. Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Snyder, SC (reprint author), Montana State Univ, Dept Biol & Phys Sci, 1500 Univ Dr, Billings, MT 59101 USA. EM ssnyder@msubillings.edu NR 17 TC 2 Z9 2 U1 2 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD SEP PY 2007 VL 107 IS 2 BP 217 EP 225 DI 10.1016/j.jqsrt.2007.02.003 PG 9 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 204PC UT WOS:000249055500002 ER PT J AU Shabanov, NV Huang, D Knjazikhin, Y Dickinson, RE Myneni, RB AF Shabanov, Nikolay V. Huang, D. Knjazikhin, Y. Dickinson, R. E. Myneni, Ranga B. TI Stochastic radiative transfer model for mixture of discontinuous vegetation canopies SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE radiative transfer; 3D effects; vegetation structure; mixture modeling ID LEAF-AREA INDEX; CLASSIFICATION AB Modeling of the radiation regime of a mixture of vegetation species is a fundamental problem of the Earth's land remote sensing and climate applications. The major existing approaches, including the linear mixture model and the turbid medium (TM) mixture radiative transfer model, provide only an approximate solution to this problem. In this study, we developed the stochastic mixture radiative transfer (SMRT) model, a mathematically exact tool to evaluate radiation regime in a natural canopy with spatially varying optical properties, that is, canopy, which exhibits a structured mixture of vegetation species and gaps. The model solves for the radiation quantities, direct input to the remote sensing/climate applications: mean radiation fluxes over whole mixture and over individual species. The canopy structure is parameterized in the SMRT model in terms of two stochastic moments: the probability of finding species and the conditional pair-correlation of species. The second moment is responsible for the 3D radiation effects, namely, radiation streaming through gaps without interaction with vegetation and variation of the radiation fluxes between different species. We performed analytical and numerical analysis of the radiation effects, simulated with the SMRT model for the three cases of canopy structure: (a) non-ordered mixture of species and gaps (TM); (b) ordered mixture of species without gaps; and (c) ordered mixture of species with gaps. The analysis indicates that the variation of radiation fluxes between different species is proportional to the variation of species optical properties (leaf albedo, density of foliage, etc.) Gaps introduce significant disturbance to the radiation regime in the canopy as their optical properties constitute major contrast to those of any vegetation species. The SMRT model resolves deficiencies of the major existing mixture models: ignorance of species radiation coupling via multiple scattering of photons (the linear mixture model) or overestimation of this coupling due to neglecting spatial clumping of species (the TM approach). Thus, based on the former experience with mixture modeling, this study establishes an advanced theoretical basis for future mixture applications. (c) 2007 Elsevier Ltd. All rights reserved. C1 Boston Univ, Dept Geog, Boston, MA 02215 USA. Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. Georgia Inst Technol, Sch Earth & Atmospher Sci, Atlanta, GA 30332 USA. RP Shabanov, NV (reprint author), Boston Univ, Dept Geog, 675 Commonwealth Ave, Boston, MA 02215 USA. EM shabanov@bu.edu RI Huang, Dong/H-7318-2014; Myneni, Ranga/F-5129-2012 OI Huang, Dong/0000-0001-9715-6922; NR 27 TC 13 Z9 14 U1 1 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD SEP PY 2007 VL 107 IS 2 BP 236 EP 262 DI 10.1016/j.jqsrt.2007.01.053 PG 27 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 204PC UT WOS:000249055500004 ER PT J AU Poston, TM Peterson, RE Cooper, AT AF Poston, T. M. Peterson, R. E. Cooper, A. T. TI Past radioactive particle contamination in the Columbia river at the Hanford site, USA SO JOURNAL OF RADIOLOGICAL PROTECTION LA English DT Article; Proceedings Paper CT 9th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems CY OCT 01-03, 2003 CL Anacapri, ITALY SP IEEE Comp Soc, Tech Comm Distributed Proc, IFIP WG 10 4, OMG, EOARD, Microsoft Corp, Ansaldo Segnalamento Ferroviario, Univ Naples Federico II AB One closed-loop and eight single-pass plutonium production reactors originally operated on the Columbia river. During the 26 years of single-pass reactor operations, small amounts of radioactive particles were released in liquid discharges to the Columbia river and were deposited in sediment and cobble along the shoreline and on islands in the river. Islands located adjacent to D island and immediately downstream of D island had the greatest density of particles. In 1979, the small particles contained between 63 and 890 kBq of cobalt-60 activity. Dose rates emanating from those particles ranged from 1 to 14 mu Gy h(-1). Because of the short half-life of cobalt-60 ( 5.3 y), the hotparticle problem at Hanford has taken care of itself through radiological decay. Some scientists have proposed that it is economically and environmentally advantageous to manage isolated low-level contaminated sites with institutional controls until the activity decays and the sites can be released rather than to pursue expensive clean-up options. C1 Battelle NW, Environm Technol Div, Richland, WA 99354 USA. RP Poston, TM (reprint author), Battelle NW, Environm Technol Div, Richland, WA 99354 USA. NR 9 TC 1 Z9 1 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0952-4746 J9 J RADIOL PROT JI J. Radiol. Prot. PD SEP PY 2007 VL 27 IS 3A SI SI BP A45 EP A50 DI 10.1088/0952-4746/27/3A/S06 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 219BA UT WOS:000250058500006 PM 17768318 ER PT J AU Moore, DS Lee, KY AF Moore, David S. Lee, Kien-Yin TI Raman spectroscopy as a tool for long-term energetic material stability studies SO JOURNAL OF RAMAN SPECTROSCOPY LA English DT Article DE Raman spectroscopy; chemical stability; polymorph stability; long-term stability ID SPECTRA AB Raman spectroscopy is shown to be useful as a tool for long-term stability studies. The stability of a novel submicron-size gamma-polymorph form of the explosive HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) was monitored up to 1 year using Raman spectroscopy. The preparation and characterization of this submicron HMX has been previously discussed. It is important to know the long-term stability of this submicron gamma-polymorph material under ambient conditions for its eventual utilization. This submicron HMX material has been found to be stable both chemically and polymorphically (to the order of 1% impurity level), even though HMX normally converts to the beta-polymorph at ambient conditions. Copyright (C) 2007 John Wiley & Sons, Ltd. C1 Los Alamos Natl Lab, Dynam & Energet Mat Div, Los Alamos, NM 87545 USA. RP Moore, DS (reprint author), Los Alamos Natl Lab, Dynam & Energet Mat Div, POB 1663, Los Alamos, NM 87545 USA. EM moored@lanl.gov RI Moore, David/C-8692-2013 NR 10 TC 8 Z9 8 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0377-0486 J9 J RAMAN SPECTROSC JI J. Raman Spectrosc. PD SEP PY 2007 VL 38 IS 9 BP 1221 EP 1224 DI 10.1002/jrs.1756 PG 4 WC Spectroscopy SC Spectroscopy GA 210QL UT WOS:000249470600020 ER PT J AU McFadden, GB Coriell, SR Gurski, KF Cotrell, DL AF McFadden, G. B. Coriell, S. R. Gurski, K. F. Cotrell, D. L. TI Convective instabilities in two liquid layers SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE Benard convection; benzenewater system; fluid bilayers; hydrodynamic stability; Marangoni convection; Rayleigh-Taylor convection AB We perform linear stability calculations for horizontal fluid bilayers, taking into account both buoyancy effects and thermocapillary effects in the presence of a vertical temperature gradient. To help understand the mechanisms driving the instability, we have performed both long- wavelength and short- wavelength analyses. The mechanism for the large wavelength instability is complicated, and the detailed form of the expansion is found to depend on the Crispation and Bond numbers. The system also allows a conventional Rayleigh- Taylor instability if heavier fluid overlies lighter fluid, and the long- wavelength analysis describes this case as well. In addition to the asymptotic analyses for large and small wavelengths, we have performed numerical calculations using materials parameters for a benzene- water system. C1 NIST, Math & Computat Sci Div, Informat Technol Lab, Gaithersburg, MD 20899 USA. George Washington Univ, Dept Math, Washington, DC 20052 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP McFadden, GB (reprint author), NIST, Math & Computat Sci Div, Informat Technol Lab, Gaithersburg, MD 20899 USA. EM mcfadden@nist.gov; sam.coriell@nist.gov; katharine.gurski@nist.gov; cotrell2@llnl.gov RI McFadden, Geoffrey/A-7920-2008; OI McFadden, Geoffrey/0000-0001-6723-2103; Gurski, Katharine/0000-0002-4589-8307 NR 16 TC 5 Z9 5 U1 0 U2 7 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD SEP-OCT PY 2007 VL 112 IS 5 BP 271 EP 281 DI 10.6028/jres.112.020 PG 11 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 229ES UT WOS:000250786400003 PM 27110470 ER PT J AU Jin, GB Choi, ES Guertin, RP Brooks, JS Booth, CH Albrecht-Schmitt, TE AF Jin, Geng Bang Choi, Eun Sang Guertin, Robert P. Brooks, James S. Booth, Corwin H. Albrecht-Schmitt, Thomas E. TI Syntheses, structure, magnetism, and optical properties of the partially ordered quaternary interlanthanide sulfides PrLnYb(2)S(6) (Ln = Tb, Dy) SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article DE interlanthanide sulfide; mixed-lanthanide sulfide ID CRYSTAL-STRUCTURE; YTTERBIUM SULFIDE; SCANDIUM SULFIDE; CERIUM; CHALCOGENIDES; ERBIUM; SE; REFINEMENT; YTTRIUM; CE AB Dark red single crystals of PrLnYb(2)S(6) (Ln = Pr/Yb, Tb, Dy) have been synthesized through the reactions of elemental rare earth metals and S using a Sb2S3 flux at 1000 degrees C. These isotypic compounds adopt the F-Ln(2)S(3) three-dimensional open-channel structure type. Eight-coordinate Pr3+ ions sit in the channels that are constructed from three different edge-shared double chains running down the b-axis that contain Yb(1)S-6 octahedra, Yb(2)S-6 octahedra, and LnS(7) monocapped trigonal prisms. Each double chain connects to four other neighbors by sharing vertices and edges. Considerable disordering in Lit positions was observed in single X-ray diffraction experiments only in the case of Pr/Yb. Least-squares refinements gave rise to the formulas of Pr1.34Yb2.66S6, of PrTbYb2S6, and PrDyYb2S6, which are confirmed by the elemental analysis and magnetic susceptibility measurements. Pr1.34Yb2.66S6, PrTbYb2S6, and PrDyYb2S6 are paramagnetic down to 2K, without any indications of long-range magnetic ordering. The optical transitions for Pr1.34Yb2.66S6, PrTbYb2S6, and PrDyYb2S6 are at approximately 1.6 eV. Crystallographic data are listed as an example for PrTbYb2S6: monoclinic, space group P2(1)/1m, a = 10.9496(10) angstrom, b = 3.9429(4)angstrom, c = 11.2206(10)angstrom, beta = 108.525(2)degrees, V = 459.33(7)angstrom(3), Z = 2. (c) 2007 Elsevier Inc. All rights reserved. C1 Auburn Univ, Dept Chem & Biochem, Auburn, AL 36849 USA. Auburn Univ, EC Leach Nucl Sci Ctr, Auburn, AL 36849 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32310 USA. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Tufts Univ, Dept Phys & Astron, Medford, MA 02155 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Albrecht-Schmitt, TE (reprint author), Auburn Univ, Dept Chem & Biochem, Auburn, AL 36849 USA. EM albreth@auburn.edu RI Booth, Corwin/A-7877-2008 NR 32 TC 3 Z9 4 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD SEP PY 2007 VL 180 IS 9 BP 2581 EP 2586 DI 10.1016/j.jssc.2007.06.032 PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 212JA UT WOS:000249591300023 ER PT J AU Stubben, C Milligan, B AF Stubben, Chris Milligan, Brook TI Estimating and analyzing demographic models using the popbio package in R SO JOURNAL OF STATISTICAL SOFTWARE LA English DT Article DE demography; matrix population model; projection matrix; vital rates; stochastic growth rate ID STAGE; AGE AB A complete assessment of population growth and viability from field census data often requires complex data manipulations, statistical routines, mathematical tools, programming environments, and graphical capabilities. We therefore designed an R package called popbio to facilitate both the construction and analysis of projection matrix models. The package consists primarily of the R translation of MATLAB code found in Caswell (2001) and Morris and Doak (2002) for the analysis of projection matrix models. The package also includes methods to estimate vital rates and construct projection matrix models from census data typically collected in plant demography studies. In these studies, vital rates can often be estimated directly from annual censuses of tagged individuals using transition frequency tables. Because the construction of projection matrix models requires careful management of census data, we describe the steps to construct a projection matrix in detail. C1 [Stubben, Chris] Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. [Milligan, Brook] New Mexico State Univ, Las Cruces, NM 88003 USA. RP Stubben, C (reprint author), Los Alamos Natl Lab, Biosci Div, POB 1663, Los Alamos, NM 87545 USA. NR 19 TC 108 Z9 109 U1 4 U2 36 PU JOURNAL STATISTICAL SOFTWARE PI LOS ANGELES PA UCLA DEPT STATISTICS, 8130 MATH SCIENCES BLDG, BOX 951554, LOS ANGELES, CA 90095-1554 USA SN 1548-7660 J9 J STAT SOFTW JI J. Stat. Softw. PD SEP PY 2007 VL 22 IS 11 BP 1 EP 23 PG 23 WC Computer Science, Interdisciplinary Applications; Statistics & Probability SC Computer Science; Mathematics GA 252EX UT WOS:000252430500001 ER PT J AU Hall, RJ Siridechadilok, B Nogales, E AF Hall, Richard. J. Siridechadilok, Bunpote Nogales, Eva TI Cross-correlation of common lines: A novel approach for single-particle reconstruction of a structure containing a flexible domain SO JOURNAL OF STRUCTURAL BIOLOGY LA English DT Article DE Cryo-EM; conformational flexibility; common lines; translation initiation ID ESCHERICHIA-COLI; CHAPERONIN GROEL; MACROMOLECULES; CLASSIFICATION; FLEXIBILITY; MICROSCOPY; SUBUNIT; IMAGES; STATES; RNA AB We describe a novel approach to sorting class averages of a structure in multiple conformational states in order to generate 3D reconstructions that account for conformational variability present in the sample. The method assumes that the relative Euler angles between class averages are known, then uses a common lines approach to match any given class against a set of distinct conformations from a selected view of the structure. We show the effectiveness of the method both on model data and on an experimental dataset for which the conformational variability is limited to a defined region within the structure. During our studies of hepatitis C virus (HCV) internal ribosome entry site (IRES) interaction with the human translation initiation factor eIF3, we observed that the IRES RNA included a flexible region holding multiple conformations. While current classification methods were used to produce two-dimensional averages of the complex showing these different conformations, no method existed for relating these averages in three dimensions. Our approach overcame these limitations, giving us structural insight that was previously not possible. (c) 2007 Elsevier Inc. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. RP Hall, RJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM RJHall@lbl.gov FU NIGMS NIH HHS [GM062989, P01 GM064692, P01 GM064692-05, R01 GM062989] NR 23 TC 10 Z9 10 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1047-8477 J9 J STRUCT BIOL JI J. Struct. Biol. PD SEP PY 2007 VL 159 IS 3 BP 474 EP 482 DI 10.1016/j.jsb.2007.05.007 PG 9 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 210RE UT WOS:000249472500015 PM 17646111 ER PT J AU Johansson, GA Tyliszczak, T Mitchell, GE Keefe, MH Hitchcock, AP AF Johansson, Goeran A. Tyliszczak, Tolek Mitchell, Gary E. Keefe, Melinda H. Hitchcock, Adam P. TI Three-dimensional chemical mapping by scanning transmission X-ray spectromicroscopy SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article DE three-dimensional chemical imaging; scanning transmission X-ray microscopy; NEXAFS spectroscopy; polystyrene microspheres; polyacrylates; tomography ID HOLLOW LATEX-PARTICLES; ADVANCED LIGHT-SOURCE; ELECTRON-MICROSCOPY; MICROBIAL BIOFILMS; TOMOGRAPHY; RESOLUTION; CELLS; RECONSTRUCTION AB Three-dimensional (3-d) chemical mapping using angle-scan tomography in a scanning transmission X-ray microscope is demonstrated. Apparatus, experimental procedures and data processing are presented and the 3-d spatial resolution is evaluated. The technique is illustrated using mapping of a low-density acrylate polyelectrolyte in and outside of polystyrene microspheres dispersed in water in a 4 mu m-diameter microcapillary. The 3-d chemical visualization provides information about the microstructure that had not previously been observed. C1 McMaster Univ, Dept Chem & BIMR, Hamilton, ON L8S 4M1, Canada. LBNL, Adv Light Source, Berkeley, CA 94720 USA. Dow Chem Co USA, Analyt Sci, Midland, MI 48667 USA. Dow Chem Co USA, Analyt Sci, Midland, MI 48667 USA. Dow Chem Co USA, Dow Latex, Midland, MI 48667 USA. RP Johansson, GA (reprint author), McMaster Univ, Dept Chem & BIMR, Hamilton, ON L8S 4M1, Canada. EM gajohansson@lbl.gov NR 42 TC 36 Z9 37 U1 0 U2 15 PU WILEY-BLACKWELL PUBLISHING, INC PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD SEP PY 2007 VL 14 BP 395 EP 402 DI 10.1107/S0909049507029962 PG 8 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 199IU UT WOS:000248690200001 PM 17717380 ER PT J AU Sanongraj, W Chen, YS Crittenden, JC Destaillats, H Hand, DW Perrarn, DL Taylor, R AF Sanongraj, Wipada Chen, Yongsheng Crittenden, John C. Destaillats, Hugo Hand, David W. Perrarn, David L. Taylor, Roy TI Mathematical model for photocatalytic destruction of organic contaminants in air SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID TIO2 FILM; OXIDATION; DEGRADATION; TRICHLOROETHYLENE; FORMALDEHYDE; PERFORMANCE; CATALYST; TOLUENE; UV AB Photocatalytic oxidation (PCO) was investigated in a bench-scale reactor for the abatement of two airborne organic contaminants: toluene and ethanol. A mathematical model that includes the impacts of light intensity, initial. contaminant concentration, catalyst thickness, and relative humidity (RH) on the degradation of organic contaminants in a photocatalytic reactor was developed to describe this process. The commercially available catalyst Degussa-PtTiO2 was selected to compare with the MTU-PtTiO2-350 catalyst, which was synthesized by the sol-gel process, platinized, and calcined at 350 degrees C. For toluene removal using the MTU-PtTiO2-350 catalyst, the degradation rate increased with increases in light intensity from 0.2 to 2.2 mW/cm(2) and in catalyst thickness from 0.00037 to 0.00361 cm. However, further increases in light intensity and catalyst thickness had only slight effect on the toluene degradation rate. Increasing the initial concentration from 6.29 to 127.9 mu g/L and the RH from 10 to 85% resulted in decreases in the toluene degradation rate. For ethanol removal using the MTU-PtTiO2-350 catalyst, the degradation rate increased more rapidly with an increase in RH from 17 to 56%; the RH had little effect on the ethanol degradation rate while it further increased from 56% to 82%. We discuss applicability of the model to estimate the influence of process variables and to evaluate photocatalyst performance. C1 Ubon Ratchathani Univ, Dept Chem Engn, Ubon Ratchathani, Thailand. Arizona State Univ, Dept Civil & Environm Engn, Tempe, AZ USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Indoor Environm Dept, Berkeley, CA 94720 USA. Michigan Technol Univ, Dept Civil & Environm Engn, Houghton, MI 49931 USA. Access Business Grp, Ada, MI USA. RP Crittenden, JC (reprint author), Ubon Ratchathani Univ, Dept Chem Engn, Ubon Ratchathani, Thailand. EM jcritt@asu.edu RI Destaillats, Hugo/B-7936-2013; Chen, Yongsheng/B-1541-2010 NR 26 TC 4 Z9 4 U1 0 U2 7 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA ONE GATEWAY CENTER, THIRD FL, PITTSBURGH, PA 15222 USA SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD SEP PY 2007 VL 57 IS 9 BP 1112 EP 1122 DI 10.3155/1047-3289.57.9.1112 PG 11 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 207BQ UT WOS:000249227000011 PM 17912930 ER PT J AU Wei, X Akincw, M AF Wei, Xiang Akincw, Mufit TI Crystal structure analysis of Si- and Zn-codoped tricalcium phosphate by neutron powder diffraction SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID STABILIZED CALCIUM PHOSPHATES; BONE-FORMATION; STRUCTURE REFINEMENT; TISSUE-CULTURE; ZINC; MAGNESIUM; SILICON; SOLUBILITY; HYDROXYAPATITE; BETA-CA3(PO4)2 AB Tricalcium phosphate (TCP) is a candidate for a temporary bone implant. Attempts were made to tune the resorption rate of implant for bone reforming by doping different levels of Si and Zn. In this paper, the crystal structure of Si- and Zn-codoped TCP (Si,Zn-Ca-3(PO4)(2) (Si,Zn-TCP)) was studied by using a time-of-flight neutron powder diffraction and the Rietveld analysis method. Si,Zn-TCP was confirmed to have a rhombohedral structure (space group R3c, Z=21), with the unit cell parameters a=b=10.3958(1) angstrom, c=37.3122(7) angstrom, alpha=beta=90 degrees, and gamma=120 degrees in the hexagonal setting. Of the five cation sites, Ca(1), Ca(2), and Ca(3) positions are still occupied by Ca with minor change in Ca-O bond distance compared with the pure beta-TCP. Whereas the Ca(5) site was totally occupied by Zn. Compared with the original Ca(5)...O distance, the shorter and more uniform Zn(5)...O bond distances show the smaller cation substitution effect and a more ideal octahedral geometry. The site Ca(4) was partially substituted by Zn and Ca,Zn(4)...O(9) bond distance is 2.808(5) angstrom, much shorter than the original 3.041(1). The Zn substitution content is calculated to be 10% of total Ca sites. A fraction of Si substitutes for P(1) sites and the substitution content is calculated to be 3.9% of total phosphorus sites. The bond valence sums of Ca,Zn(4) is 0.97, higher than 0.67 for Ca(4) in beta-TCP. Other Ca and Zn(5) sites are close to 2.0. C1 Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Akincw, M (reprint author), Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. EM makinc@iastate.edu NR 42 TC 10 Z9 10 U1 1 U2 5 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD SEP PY 2007 VL 90 IS 9 BP 2709 EP 2715 DI 10.1111/j.1551-2916.2007.01764.x PG 7 WC Materials Science, Ceramics SC Materials Science GA 207UO UT WOS:000249276800005 ER PT J AU Pappacena, KE Faber, KT Wang, H Porter, WD AF Pappacena, K. E. Faber, K. T. Wang, H. Porter, W. D. TI Thermal conductivity of porous silicon carbide derived from wood precursors SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID BIOMORPHOUS SISIC-CERAMICS; MECHANICAL-PROPERTIES; HEAT-CAPACITY; FLASH METHOD; MICROSTRUCTURE; DIFFUSIVITY; BEHAVIOR; INFILTRATION; COMPOSITES; SHOCK AB Biomorphic silicon carbide (bioSiC), a novel porous ceramic derived from natural wood precursors, has potential applicability at high temperatures, particularly when rapid temperature changes occur. The thermal conductivity of bioSiC from five different precursors was experimentally determined using flash diffusivity and specific heat measurements at temperatures ranging from room temperature to 1100 degrees C. The results were compared with values obtained from object-oriented finite-element analysis (OOF). OOF was also used to model and understand the heat-flow paths through the complex bioSiC microstructures. C1 Northwestern Univ, Robert R McCormick Sch Engn & Appl Sci, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Faber, KT (reprint author), Northwestern Univ, Robert R McCormick Sch Engn & Appl Sci, Dept Mat Sci & Engn, Evanston, IL 60208 USA. EM k-faber@northwestern.edu RI Faber, Katherine/B-6741-2009; Wang, Hsin/A-1942-2013 OI Wang, Hsin/0000-0003-2426-9867 NR 41 TC 28 Z9 28 U1 0 U2 18 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD SEP PY 2007 VL 90 IS 9 BP 2855 EP 2862 DI 10.1111/j.1551-2916.2007.01777.x PG 8 WC Materials Science, Ceramics SC Materials Science GA 207UO UT WOS:000249276800030 ER PT J AU Brennecka, GL Payne, DA Sarin, P Zuo, JM Kriven, WM Hellwig, H AF Brennecka, Geoff L. Payne, David A. Sarin, Pankaj Zuo, J.-M. Kriven, Waltraud M. Hellwig, Holger TI Phase transformations in the high-temperature form of pure and TiO2-stabilized Ta2O5 SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID TANTALUM OXIDE COATINGS; (TA2O5)(1-X)(TIO2)(X) CERAMICS; MICROSTRUCTURAL EVOLUTION; DIELECTRIC-PROPERTIES; SYSTEM TA2O5-TIO2; RESIDUAL-STRESS; ALPHA-TA2O5; PENTOXIDE; ADDITIONS; TIO2 AB The high-temperature forms of undoped tantalum pentoxide (H-100Ta(2)O(5)) and TiO2-modified Ta2O5 (H-92Ta(2)O(5)-8TiO(2)) were investigated by in situ synchrotron X-ray diffraction and Raman scattering measurements. Two unquenchable and reversible phase transformations were observed in pure H-Ta2O5, while only one was detected for TiO2-stabilized H-Ta2O5. Diffraction studies were consistent with displasive transformations, but hot-stage Raman spectroscopy indicated the existence of transient intermediate forms during the transformations. Use of complementary techniques enabled the reinterpretation of phase transformations in light of a newly proposed crystal structure model for H-Ta2O5, and emphasized the structural contributions of the oxygen sublattice. C1 Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Univ Illinois, Dept Geol, Urbana, IL 61801 USA. RP Brennecka, GL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM geoff.brennecka@gmail.com RI Brennecka, Geoff/J-9367-2012 OI Brennecka, Geoff/0000-0002-4476-7655 NR 30 TC 8 Z9 9 U1 2 U2 21 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD SEP PY 2007 VL 90 IS 9 BP 2947 EP 2953 DI 10.1111/j.1551-2916.2007.01790.x PG 7 WC Materials Science, Ceramics SC Materials Science GA 207UO UT WOS:000249276800044 ER PT J AU Page, JS Kelly, RT Tang, K Smith, RD AF Page, Jason S. Kelly, Ryan T. Tang, Keqi Smith, Richard D. TI Ionization and transmission efficiency in an electrospray ionization-mass spectrometry interface SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID ELECTRODYNAMIC ION FUNNEL; ATMOSPHERIC-PRESSURE; MULTICAPILLARY INLET; SENSITIVITY; PROTEOMICS; CAPILLARIES; EMITTERS; MS AB The ionization and transmission efficiencies of an electrospray ionization (ESI) interface were investigated to advance the understanding of how these factors affect mass spectrometry (MS) sensitivity. In addition, the effects of the ES emitter distance to the inlet, solution flow rate, and inlet temperature were characterized. Quantitative measurements of ES current loss throughout the ESI interface were accomplished by electrically isolating the front surface of the interface from the inner wall of the heated inlet capillary, enabling losses on the two surfaces to be distinguished. In addition, the ES current lost to the front surface of the ESI interface was spatially profiled with a linear array of 340-mu m-diameter electrodes placed adjacent to the inlet capillary entrance. Current transmitted as gas-phase ions was differentiated from charged droplets and solvent clusters by measuring sensitivity with a single quadrupole mass spectrometer. The study revealed a large sampling efficiency into the inlet capillary (> 90% at an emitter distance of I mm), a global rather than a local gas dynamic effect on the shape of the ES plume resulting from the gas flow conductance limit of the inlet capillary, a large (> 80%) loss of analyte ions after transmission through the inlet arising from incomplete desolvation at a solution flow rate of 1.0 mu L/min, and a decrease in analyte ions peak intensity at lower temperatures, despite a large increase in ES current transmission efficiency. C1 Pacific NW Natl Lab, Div Biol Sci, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Biol Syst Anal & Mass Spectrometry, 3335 Q Ave,PO Box 999,MS K8-98, Richland, WA 99352 USA. EM rds@pnl.gov RI Smith, Richard/J-3664-2012; Kelly, Ryan/B-2999-2008 OI Smith, Richard/0000-0002-2381-2349; Kelly, Ryan/0000-0002-3339-4443 FU NCI NIH HHS [R21 CA-126191]; NCRR NIH HHS [RR-18522]; NIAID NIH HHS [Y1-AI-4894-01] NR 40 TC 108 Z9 108 U1 3 U2 43 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD SEP PY 2007 VL 18 IS 9 BP 1582 EP 1590 DI 10.1016/j.jasms.2007.05.018 PG 9 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 210NF UT WOS:000249462200003 PM 17627841 ER PT J AU Cannon, WR Taasevigen, D Baxter, DJ Laskin, J AF Cannon, William R. Taasevigen, Danny Baxter, Douglas J. Laskin, Julia TI Evaluation of the influence of amino acid composition on the propensity for collision-induced dissociation of model peptides using molecular dynamics simulations SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID SURFACE-INDUCED DISSOCIATION; TANDEM MASS-SPECTROMETRY; FT-ICR MS; CHARGED TRYPTIC PEPTIDES; GAS-PHASE BASICITY; PROTEIN IDENTIFICATION; PROTONATED PEPTIDES; STATISTICAL CHARACTERIZATION; FRAGMENTATION ENERGETICS; SPECTRUM LIBRARIES AB The dynamical behavior of model peptides was evaluated with respect to their ability to form internal proton donor-acceptor pairs using molecular dynamics simulations. The proton donor-acceptor pairs are postulated to be prerequisites for peptide bond cleavage resulting in formation of b and y ions during low-energy collision-induced dissociation in tandem mass spectrometry (MS/MS). The simulations for the polyalanine pentamer Ala(5)H(+) were compared with experimental data from energy-resolved surface induced dissociation (SID) studies. The results of the simulation are insightful into the events that likely lead up to the fragmentation of peptides. Nine-mer polyalanine-based model peptides were used to examine the dynamical effect of each of the 20 common amino acids on the probability to form donor-acceptor pairs at labile peptide bonds. A range of probabilities was observed as a function of the substituted amino acid. However, the location of the peptide bond involved in the donor-acceptor pair plays a critical role in the dynamical behavior. This influence of position on the probability of forming a donor-acceptor pair would be hard to predict from statistical analyses on experimental spectra of aggregate, diverse peptides. In addition, the inclusion of basic side chains in the model peptides alters the probability of forming donor-acceptor pairs across the entire backbone. In this case, there are still more ionizing protons than basic residues, but the side chains of the basic amino acids form stable hydrogen bond networks with the peptide carbonyl oxygens and thus act to prevent free access of "mobile protons" to labile peptide bonds. It is clear from the work that the identification of peptides from low-energy CID using automated computational methods should consider the location of the fragmenting bond as well as the amino acid composition. C1 Pacific NW Natl Lab, Computat Biol & Bioinformat Grp, Computat & Informat Sci Directorate, Richland, WA 99352 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Mol Sci Comp Facil, Richland, WA 99352 USA. Pacific NW Natl Lab, Fundamental Sci Directorate, Chem Struct & Dynam Grp, Richland, WA 99352 USA. RP Cannon, WR (reprint author), Pacific NW Natl Lab, Computat Biol & Bioinformat Grp, Computat & Informat Sci Directorate, POB 999 MS K5-12, Richland, WA 99352 USA. EM william.cannon@pnl.gov RI Cannon, William/K-8411-2014; Laskin, Julia/H-9974-2012 OI Cannon, William/0000-0003-3789-7889; Laskin, Julia/0000-0002-4533-9644 NR 45 TC 8 Z9 8 U1 0 U2 7 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD SEP PY 2007 VL 18 IS 9 BP 1625 EP 1637 DI 10.1016/j.jasms.007.06.005 PG 13 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 210NF UT WOS:000249462200008 PM 17651984 ER PT J AU Shvartsburg, AA Smith, RD AF Shvartsburg, Alexandre A. Smith, Richard D. TI Scaling of the resolving power and sensitivity for planar FAIMS and mobility-based discrimination in flow- and field-driven analyzers SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID SPECTROMETRY-MASS-SPECTROMETRY; GAS-PHASE SEPARATIONS; ASYMMETRIC WAVE-FORMS; ION MOBILITY; DEGRADATION-PRODUCTS; MS; ELECTROSPRAY; CHROMATOGRAPHY; RESOLUTION; PEPTIDES AB Continuing development of the technology and applications of field asymmetric waveform ion mobility spectrometry (FAIMS) calls for better understanding of its limitations and factors that govern them. While key performance metrics such as resolution and ion transmission have been calculated for specific cases employing numerical simulations, the underlying physical trends remained obscure. Here we determine that the resolving power of planar FAIMS scales as the square root of separation time and sensitivity drops exponentially at the rate controlled by absolute ion mobility and several instrument parameters. A strong dependence of ion transmission on mobility severely discriminates against species with higher mobility, presenting particular problems for analyses of complex mixtures. While the time evolution of resolution and sensitivity is virtually identical in existing FAIMS systems using gas flow and proposed devices driven by electric field, the distributions of separation times are not. The inverse correlation between mobility (and thus diffusion speed) and residence time for ions in field-driven FAIMS greatly reduces the mobility-based discrimination and provides much more uniform separations. Under typical operating conditions, the spread of elimination rates for commonly analyzed ions is reduced from > 5 times in flow-driven to 1.6 times in field-driven FAIMS while the difference in resolving power decreases from similar to 60% to similar to 15%. C1 Pacific NW Natl Lab, Div Biol Sci, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Div Biol Sci, 3335 Q Ave K8-98,POB 999, Richland, WA 99352 USA. EM rds@pnl.gov RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 FU NCRR NIH HHS [RR 18522] NR 51 TC 30 Z9 30 U1 1 U2 8 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD SEP PY 2007 VL 18 IS 9 BP 1672 EP 1681 DI 10.1016/j.jasms.2007.06.013 PG 10 WC Biochemical Research Methods; Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Biochemistry & Molecular Biology; Chemistry; Spectroscopy GA 210NF UT WOS:000249462200013 PM 17723907 ER PT J AU Poyneer, LA Macintosh, BA Veran, JP AF Poyneer, Lisa A. Macintosh, Bruce A. Veran, Jean-Pierre TI Fourier transform wavefront control with adaptive prediction of the atmosphere SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID OPTICS; OPTIMIZATION AB Predictive Fourier control is a temporal power spectral density-based adaptive method for adaptive optics that predicts the atmosphere under the assumption of frozen flow. The predictive controller is based on Kalman filtering and a Fourier decomposition of atmospheric turbulence using the Fourier transform reconstructor. It provides a stable way to compensate for arbitrary numbers of atmospheric layers. For each Fourier mode, efficient and accurate algorithms estimate the necessary atmospheric parameters from closed-loop telemetry and determine the predictive filter, adjusting as conditions change. This prediction improves atmospheric rejection, leading to significant improvements in system performance. For a 48 x 48 actuator system operating at 2 kHz, five-layer prediction for all modes is achievable in under 2 x 10(9) floating-point operations/s. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Herzberg Inst Astrophys, Victoria, BC V9E 2E7, Canada. RP Poyneer, LA (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave, Livermore, CA 94550 USA. EM poyneer1@llnl.gov NR 23 TC 55 Z9 55 U1 0 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1084-7529 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD SEP PY 2007 VL 24 IS 9 BP 2645 EP 2660 DI 10.1364/JOSAA.24.002645 PG 16 WC Optics SC Optics GA 215MN UT WOS:000249813000017 PM 17767234 ER PT J AU Chowdhury, MH Gray, SK Pond, J Geddes, CD Aslan, K Lakowicz, JR AF Chowdhury, Mustafa H. Gray, Stephen K. Pond, James Geddes, Chris D. Aslan, Kadir Lakowicz, Joseph R. TI Computational study of fluorescence scattering by silver nanoparticles SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID METAL-ENHANCED FLUORESCENCE; DIFFERENCE TIME-DOMAIN; ISLAND FILMS; ELECTROMAGNETIC SCATTERING; MAXWELLS EQUATIONS; NUMERICAL-SOLUTION; LIGHT-SCATTERING; ICE CRYSTALS; MOLECULES; SURFACES AB We study the nature of fluorescence scattering by a radiating fluorophore placed near a metal nanoparticle with the finite-difference time-domain method. Angle-resolved light-scattering distributions are contrasted with those that result when ordinary plane waves are scattered by the nanoparticle. For certain sized nanoparticles and fluorophore dipoles oriented parallel to the metal surface, we find that the highest scattered fluorescence emission is directed back toward the fluorophore, which is very different from plane-wave scattering. The largest enhancements of far-field radiation are found when the dipole is oriented normal to the surface. We also examined the effect of the fluorophore on the near field around the particle. The fields can be enhanced or quenched compared to the isolated fluorophore and exhibit strong dependence on fluorophore orientation, as well as interesting spatial variations around the nanoparticle. (c) 2007 Optical Society of America. C1 Univ Maryland, Sch Med, Ctr Med Biotechnol, Ctr Fluorescence Spect, Baltimore, MD 21201 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA. Lumer Solut Inc, Vancouver, BC V6C 1H2, Canada. Univ Maryland, Maryland Biotechnol Inst, Ctr Med Biotechnol, Inst Fluorescence,Lab Adv Med Plasmon, Baltimore, MD 21201 USA. RP Lakowicz, JR (reprint author), Univ Maryland, Sch Med, Ctr Med Biotechnol, Ctr Fluorescence Spect, 725 W Lombard St, Baltimore, MD 21201 USA. EM lakowicz@cfs.umbi.umd.edu OI ASLAN, KADIR/0000-0002-7617-0175 FU NCRR NIH HHS [P41 RR008119]; NHGRI NIH HHS [R01 HG002655-01, R01 HG002655, R01 HG002655-02, R01 HG002655-03, R01 HG002655-04A1, R01 HG002655-05, R01 HG002655-06]; NIBIB NIH HHS [R01 EB000682, R01 EB000682-01, R01 EB000682-02, R01 EB000682-03, R01 EB000682-04, R01 EB000682-05, R01 EB006521, R01 EB006521-01A1, R01 EB006521-02, R01 EB006521-03]; NIGMS NIH HHS [R21 GM070929] NR 29 TC 35 Z9 35 U1 0 U2 11 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 EI 1520-8540 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD SEP PY 2007 VL 24 IS 9 BP 2259 EP 2267 DI 10.1364/JOSAB.24.002259 PG 9 WC Optics SC Optics GA 215XO UT WOS:000249842500032 PM 19777118 ER PT J AU Chi, W Sampath, S Wang, H AF Chi, Weiguang Sampath, Sanjay Wang, Hsin TI Comparison of the thermal transport property measurements of thermally sprayed coatings by the laser and xenon flash techniques SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Article DE laser flash; xenon flash; thermal diffusivity ID BARRIER COATINGS; MICROSTRUCTURE; DIFFUSIVITY AB Development of precise and reliable measurement methods is an important step in the study of the thermal transport property of inherently complex systems such as thermally sprayed coatings. In this study, the applicability and repeatability of both the laser and xenon flash techniques have been investigated through the measurements on the coatings made from ceramics, metals, alloys, and composites. For the four series of material systems, issues such as the effect of powder morphology, coating thickness, spraying technique, chemical composition, and oxidation on the thermal diffusivity as well as the corresponding measurement repeatability are assessed. This investigation provides information necessary for precise and reliable characterization of the thermal transport property of various thermally sprayed coatings. C1 SUNY Stony Brook, Ctr Thermal Spray Res, Stony Brook, NY 11794 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Chi, W (reprint author), SUNY Stony Brook, Ctr Thermal Spray Res, Stony Brook, NY 11794 USA. EM chi_weiguang@yahoo.com RI Wang, Hsin/A-1942-2013 OI Wang, Hsin/0000-0003-2426-9867 NR 17 TC 3 Z9 3 U1 0 U2 2 PU ASM INT PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD SEP PY 2007 VL 16 IS 3 BP 444 EP 448 DI 10.1007/s11666-007-9049-0 PG 5 WC Materials Science, Coatings & Films SC Materials Science GA 207MP UT WOS:000249255500017 ER PT J AU Sun, Y Liu, Z Pianetta, P AF Sun, Yun Liu, Zhi Pianetta, Piero TI Surface dipole formation and lowering of the Work function by Cs adsorption on InP(100) surface SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article ID GAAS(100) SURFACE; CESIUM; STATES; CHEMISORPTION; CS/GAAS(110); INTERFACES; MODEL; GAP; NA AB The Cs adsorption on InP(100) surface is studied with synchrotron radiation photoelectron spectroscopy. The charge transfer from Cs to the InP substrate is observed from the Cs induced In 4d and P 2p components, and this charge transfer results in surface dipole formation and lowering of the work function. The Cs 4d intensity saturates at coverage of 1 ML. However, a break point is observed at 0.5 ML, which coincides with the achievement of the minimum work function. This break point is due to the different vertical placements of the first and the second half monolayer of Cs atoms. Based on this information, a simple bilayer structure for the Cs layer is presented. This bilayer structure is consistent with the behavior of the charge transfer from the Cs to the InP substrate at different Cs coverages. This, in turn, explains why the work function decreases to a minimum at 0.5 ML of Cs and remains almost constant beyond this coverage. The depolarization of the surface dipoles is attributed to the saturation of charge transfer to the surface In atoms and the polarization of the Cs atoms in the second half monolayer induced by the positively charged Cs atoms in the first half monolayer. (c) 2007 American Vacuum Society. C1 Stanford Synchrotron Radiat Lab, Stanford, CA 94025 USA. RP Sun, Y (reprint author), Stanford Synchrotron Radiat Lab, Stanford, CA 94025 USA. EM ssun@slac.stanford.edu RI Liu, Zhi/B-3642-2009 OI Liu, Zhi/0000-0002-8973-6561 NR 27 TC 11 Z9 11 U1 1 U2 7 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD SEP-OCT PY 2007 VL 25 IS 5 BP 1351 EP 1356 DI 10.1116/1.2753845 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 213JZ UT WOS:000249664400004 ER PT J AU Naulleau, PP Cain, JP AF Naulleau, Patrick P. Cain, Jason P. TI Experimental and model-based study of the robustness of line-edge roughness metric extraction in the presence of noise SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article AB As critical dimensions shrink, line edge roughness (LER) and linewidth roughness (LWR) become of increasing concern. Crucial to the goal of reducing LER is its accurate characterization. LER has traditionally been represented as a single rms value. More recently, the use of power spectral density (PSD), height-height correlation (HHCF), and a versus length plots has been proposed in order to extract the additional spatial descriptors of correlation length and roughness exponent. Here, the authors perform a modeling-based noise-sensitivity study on the extraction of spatial descriptors from line-edge data as well as an experimental study of the robustness of these various descriptors using a large data set of recent extreme-ultraviolet exposure data. The results show that in the presence of noise and in the large data set limit, the PSD method provides higher accuracy in the extraction of the roughness exponent, whereas the HHCF method provides higher accuracy for the correlation length. On the other hand, when considering precision, the HHCF method is superior for both metrics. (C) 2007 American Vacuum Society. C1 Lawrence Berkeley Natl Lab, Ctr X Ray Opt, Berkeley, CA 94720 USA. Univ Calif Berkeley, EECS Dept, Berkeley, CA 94720 USA. RP Naulleau, PP (reprint author), Lawrence Berkeley Natl Lab, Ctr X Ray Opt, Berkeley, CA 94720 USA. EM pnaulleau@lbl.gov NR 10 TC 23 Z9 23 U1 0 U2 3 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD SEP-OCT PY 2007 VL 25 IS 5 BP 1647 EP 1657 DI 10.1116/1.2778697 PG 11 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 224FS UT WOS:000250433500019 ER PT J AU Grierson, DS Sumant, AV Konicek, AR Abrecht, M Birrell, J Auciello, O Carlisle, JA Scharf, TW Dugger, MT Gilbert, PUPA Carpick, RW AF Grierson, David S. Sumant, Anirudha V. Konicek, Andrew R. Abrecht, Mike Birrell, J. Auciello, Orlando Carlisle, John A. Scharf, Thomas W. Dugger, Michael T. Gilbert, P. U. P. A. Carpick, Robert W. TI Tribochemistry and material transfer for the ultrananocrystalline diamond-silicon nitride interface revealed by x-ray photoelectron emission spectromicroscopy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID PHOTOEMISSION ELECTRON-MICROSCOPY; THIN-FILMS; WEAR; CHEMISTRY; IDENTIFICATION; SPECTROSCOPY; ABSORPTION; FRICTION; YIELD; PEEM AB The authors report tribochemical changes due to sliding of a silicon nitride (Si3N4) ball against an ultrananocrystalline diamond (UNCD) thin film. Unidirectional sliding wear measurements were conducted for 2000 cycles using a ball-on-disk apparatus with a 3/16 in. diameter Si3N4 ball at a sliding speed of 3.3 mm/s and a normal load of 98.0 mN (nominal Hertzian stress of 0.6 GPa) in a nitrogen environment at 50% relative humidity at room temperature. The wear track produced on the UNCD film was analyzed by X-ray photoelectron emission spectromicroscopy (X-PEEM) combined with X-ray absorption near-edge structure (XANES) spectroscopy to identify and spatially resolve chemical changes inside the wear track, particularly rehybridization of carbon. XANES spectra show that SiOx complexes are deposited within the wear track. Very little rehybridization of the UNCD from its primarily sp(3) bonding configuration to sp(2) bonding is observed, and there is no observable oxidation of the UNCD, pointing to the impressive stability of the film under significant tribological loading conditions. Raman spectroscopy of the worn portion of the Si3N4 ball shows that disordered carbon is found on the worn surface. The authors attribute the formation of SiOx complexes within the wear track to wear of the ball and subsequent deposition into the track. The authors attribute the disordered carbon on the Si3N4 ball to removal of sp(2)-bonded carbon from the UNCD surface and subsequent accumulation onto the ball's surface. This work demonstrates the potential of X-PEEM for the study of tribochemical modifications of carbon-based thin film surfaces. (C) 2007 American Vacuum Society. C1 Univ Wisconsin, Dept Engn Phys, Madison, WI 53706 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Ctr Synchrotron Radiat, Stoughton, WI 53589 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Grierson, DS (reprint author), Univ Wisconsin, Dept Engn Phys, Madison, WI 53706 USA. RI Gilbert, Pupa/A-6299-2010 OI Gilbert, Pupa/0000-0002-0139-2099 NR 29 TC 12 Z9 12 U1 1 U2 5 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD SEP-OCT PY 2007 VL 25 IS 5 BP 1700 EP 1705 DI 10.1116/1.2782428 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 224FS UT WOS:000250433500026 ER PT J AU Rolandi, M Okawa, D Backer, SA Zettl, A Frechet, JMJ AF Rolandi, Marco Okawa, David Backer, Scott A. Zettl, Alex Frechet, Jean M. J. TI Fabrication of magnetic force microscopy probes via localized electrochemical deposition of cobalt SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Letter ID RESOLUTION; SENSORS AB Magnetic force microscopy probes were obtained via the solution phase electrochemical deposition of cobalt nanostructures at the probe apexes. Single tips were fabricated in an atomic force microscope fluid cell. Multiple tips were produced in a single batch with an alternating potential in an electrochemical cell. The probes achieve 50 nm spatial resolution. (C) 2007 American Vacuum Society. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Rolandi, M (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM frechet@berkeley.edu RI Zettl, Alex/O-4925-2016 OI Zettl, Alex/0000-0001-6330-136X NR 19 TC 2 Z9 2 U1 0 U2 1 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD SEP-OCT PY 2007 VL 25 IS 5 BP L39 EP L42 DI 10.1116/1.2766935 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 224FS UT WOS:000250433500001 ER PT J AU Fristachi, A Rice, G AF Fristachi, Anthony Rice, Glenn TI Estimation of the total daily oral intake of NDMA attributable to drinking water SO JOURNAL OF WATER AND HEALTH LA English DT Article DE DBPs; disinfection by-products; drinking water; exposure assessment; NDMA; N-Nitrosodimethylamine ID N-NITROSODIMETHYLAMINE NDMA; BY-PRODUCTS; LOGNORMAL DISTRIBUTIONS; NITROSO COMPOUNDS; NITROSAMINES; FOODS; BEVERAGES; SMOKE; BACON; RISK AB Disinfection with chlorine and chloramine leads to the formation of many disinfection by-products including N-Nitrosodimethylamine (NDMA). Because NDMA is a probable human carcinogen, public health officials are concerned with its occurrence in drinking water. The goal of this study was to estimate NDMA concentrations from exogenous (i.e., drinking water and food) and endogenous (i.e., formed in the human body) sources, calculate average daily doses for ingestion route exposures and estimate the proportional oral intake (POI) of NDMA attributable to the consumption of drinking water relative to other ingestion sources Of NDMA. The POI is predicted to be 0.02% relative to exogenous and enclogenous NDMA sources combined. when only exogenous sources are considered, the POI was predicted to be 2.7%. The exclusion of endogenously formed NDMA causes the POI to increase dramatically, reflecting its importance as a potentially major source of exposure and uncertainty in the model. Although concentrations of NDMA in foods are small and human exposure to NDMA from foods is quite low, the contribution from food is predicted to be high relative to that of drinking water. The mean concentration of NDMA in drinking water would need to increase from 2.1 X 10(-3) mu g/L to 0.10 mu g/L, a 47-fold increase, for the POI to reach 1%, relative to all sources of NDMA considered in our model, suggesting that drinking water consumption is most likely a minor source of NDMA exposure. C1 US EPA, Off Res & Dev, Natl Ctr Environm Assessment, Oak Ridge Inst Sci & Educ, Cincinnati, OH 45268 USA. RP Fristachi, A (reprint author), US EPA, Off Res & Dev, Natl Ctr Environm Assessment, Oak Ridge Inst Sci & Educ, 26 W,Martin Luther King Dr,MS-A110, Cincinnati, OH 45268 USA. EM afristac@jhsph.edu NR 55 TC 23 Z9 23 U1 1 U2 15 PU I W A PUBLISHING PI LONDON PA ALLIANCE HOUSE, 12 CAXTON ST, LONDON SW1H0QS, ENGLAND SN 1477-8920 J9 J WATER HEALTH JI J. Water Health PD SEP PY 2007 VL 5 IS 3 BP 341 EP 355 DI 10.2166/wh.2007.030 PG 15 WC Environmental Sciences; Public, Environmental & Occupational Health; Microbiology; Water Resources SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Microbiology; Water Resources GA 204EE UT WOS:000249025600002 PM 17878549 ER PT J AU Son, JT Cairns, E AF Son, Jong-Tae Cairns, Elton TI Structure and electrochemical characterization of LiNL0.3Co0.3Mn0.3Fe0.1O2 cathode for lithium secondary battery SO KOREAN JOURNAL OF CHEMICAL ENGINEERING LA English DT Article DE cathode material; LiNi0.3Co0.3Mn0.3Fe0.1O2; sol-gel; lithium ion battery ID INSERTION MATERIAL; ION BATTERIES; ELECTRODE MATERIALS; LIMNO2; LICO1/3NI1/3MN1/3O2; R(3)OVER-BAR-M; INTERCALATION AB A lithium insertion material having the composition LiNi0.3Co0.3Mn0.3Fe0.1O2 was synthesized by simple sol-gel method. The structural and electrochemical properties of the sample were investigated using X-ray diffraction spectroscopy (XRD) and the galvanostatic charge-discharge method. Rietvelt analysis of the XRD patterns shows that this compound can be classified as alpha-NaFeO2 structure type (R3m; a=2.8689(5) angstrom and 14.296(5) angstrom in hexagonal setting). Rietvelt fitting shows that a relatively large amount of Fe and Ni ion occupy the Li layer (3a site) and a relatively large amount of Li occupies the transition metal layer (3b site). LiN0.3Co0.3Mn0.3Fe0.1O2 when cycled in the voltage range 4.3-2.8 V gives an initial discharge capacity of 120 mAh/g, and stable cycling performance. LiNi0.3Co0.3Mn0.3Fe0.1O2 in the voltage range 2.8-4.5 V has a discharge capacity of 140 mAh/g, and exhibits a significant loss in capacity during cycling. Ex-situ XRD measurements were performed to study the structure changes of the samples after cycling between 2.8-4.3 V and 2.8-4.5 V for 20 cycles. The XRD and electrochemical results suggested that cation mixing in this layered structure oxide could be causing degradation of the cell capacity. C1 EO Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Son, JT (reprint author), EO Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. EM jtson@kaist.ac.kr RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 18 TC 9 Z9 9 U1 0 U2 12 PU KOREAN INST CHEM ENGINEERS PI SEOUL PA #307 REGENT RIVER VIEW OFFICE, 547-8 KUI-DONG SUNGDONG-KU, SEOUL 133-200, SOUTH KOREA SN 0256-1115 J9 KOREAN J CHEM ENG JI Korean J. Chem. Eng. PD SEP PY 2007 VL 24 IS 5 BP 888 EP 891 DI 10.1007/s11814-007-0060-4 PG 4 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 219IC UT WOS:000250077100029 ER PT J AU Gorelik, LY Kulinich, SI Shekhter, RI Jonson, M Vinokur, VM AF Gorelik, L. Y. Kulinich, S. I. Shekhter, R. I. Jonson, M. Vinokur, V. M. TI Giant super-Poissonian shot noise in spin-polarized SET structures SO LOW TEMPERATURE PHYSICS LA English DT Article; Proceedings Paper CT International Conference on Statistical Physics CY SEP 12-15, 2006 CL Kharkiv, UKRAINE AB We study transport of spin-polarized electrons through a magnetic single-electron transistor (SET) in the presence of an external magnetic field. Assuming the SET to have a nanometer-sized central island with a single electron level, we find that the zero-frequency shot noise diverges as the on-dot spin-flip rate goes to zero, provided the source and drain leads are completely polarized in the same direction. We present an analytical expression for the low-frequency super-Poissonian shot noise that allows one to specify the necessary conditions for the experimental observation of the phenomenon. (c) 2007 American Institute of Physics. C1 Chalmers, Dept Appl Phys, S-41296 Gothenburg, Sweden. Univ Gothenburg, Dept Phys, S-41296 Gothenburg, Sweden. BI Verkin Inst Low Temperature Phys & Engn, UA-61103 Kharkov, Ukraine. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RP Gorelik, LY (reprint author), Chalmers, Dept Appl Phys, S-41296 Gothenburg, Sweden. EM gorelik@fy.chalmers.se RI Jonson, Mats/D-6545-2011 NR 13 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1063-777X J9 LOW TEMP PHYS+ JI Low Temp. Phys. PD SEP PY 2007 VL 33 IS 9 BP 757 EP 761 DI 10.1063/1.2780168 PG 5 WC Physics, Applied SC Physics GA 213UL UT WOS:000249692500004 ER PT J AU Musial, W AF Musial, WaIt TI Offshore wind electricity: A viable energy option for the coastal united states SO MARINE TECHNOLOGY SOCIETY JOURNAL LA English DT Article AB U.S. offshore wind energy resources are abundant, indigenous, and broadly dispersed among the most expensive and highly constrained electricity load centers. Economic capacity expansion models developed at the National Renewable Energy Laboratory show that offshore wind energy can compete in future U.S. electric energy markets without major changes in the market variables or revolutionary technological breakthroughs. However, significant research, development, and deployment will be needed to bring the current technology through a course of cost reductions. To maximize the resource potential, these reductions need to be made along parallel technology paths that will expand the available resource by allowing wind turbines to be installed in deep water. Analysis shows that incremental technology improvements leading to moderate cost reductions, and reasonable increases in the cost of conventional energy will help offshore wind achieve cost competitiveness by 2030 and become a major contributor to the energy supply of the United States. This paper describes a wide range of technical research and development that can reduce costs and improve technology for deep water deployment. C1 Natl Renewable Energy Lab, Natl Wind Technol Ctr, Golden, CO 80401 USA. RP Musial, W (reprint author), Natl Renewable Energy Lab, Natl Wind Technol Ctr, Golden, CO 80401 USA. NR 49 TC 8 Z9 8 U1 5 U2 9 PU MARINE TECHNOLOGY SOC INC PI COLUMBIA PA 5565 STERRETT PLACE, STE 108, COLUMBIA, MD 21044 USA SN 0025-3324 J9 MAR TECHNOL SOC J JI Mar. Technol. Soc. J. PD FAL PY 2007 VL 41 IS 3 BP 32 EP 43 PG 12 WC Engineering, Ocean; Oceanography SC Engineering; Oceanography GA 231WJ UT WOS:000250979600005 ER PT J AU Trimm, M AF Trimm, Marvin TI From the President - A new season begins SO MATERIALS EVALUATION LA English DT Editorial Material C1 Savannah River Natl Lab, Aiken, SC 29801 USA. RP Trimm, M (reprint author), Savannah River Natl Lab, 730-A Room 102, Aiken, SC 29801 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC NONDESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 USA SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD SEP PY 2007 VL 65 IS 9 BP 859 EP 859 PG 1 WC Materials Science, Characterization & Testing SC Materials Science GA 207DB UT WOS:000249230700001 ER PT J AU Roach, D AF Roach, Dennis TI Sensors signal when damage is detected SO MATERIALS PERFORMANCE LA English DT News Item C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Roach, D (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NATL ASSOC CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 USA SN 0094-1492 J9 MATER PERFORMANCE JI Mater. Perform. PD SEP PY 2007 VL 46 IS 9 BP 18 EP 19 PG 2 WC Materials Science, Characterization & Testing SC Materials Science GA 208VL UT WOS:000249347200006 ER PT J AU Boitsov, IE Grishechkin, SK Glugla, MJ Kanashenko, SL Causey, RA Hassanein, AM Yukhimchuk, AA AF Boitsov, I. E. Grishechkin, S. K. Glugla, M. J. Kanashenko, S. L. Causey, R. A. Hassanein, A. M. Yukhimchuk, A. A. TI Effect of radiogenic (3)He and hydrogen on the mechanical properties and structure of 12Kh18N10T steel SO MATERIALS SCIENCE LA English DT Article AB We present some results of studying the influence of high-pressure hydrogen (80 MPa), radiogenic (3)He (with concentrations up to 130 appm), and their joint action on the mechanical properties and structure of 12Kh18N10T steel in the temperature range from 293 to 873 K. We describe the procedure of tests of specimens containing (3)He. It has been established that the joint action of hydrogen and (3)He affects slightly the ultimate strength of the specimens. Saturation of steel with radiogenic (3)He by the method of "tritium trick" increases its yield strength. Hardening of the steel caused by helium increases with temperature and (3)He concentration and, at 873 K, is accompanied by substantial embrittlement. We also present results of the fractographic analysis of specimens tested under different conditions. C1 [Boitsov, I. E.; Grishechkin, S. K.; Yukhimchuk, A. A.] All Russian Sci & Res Inst Expt Phys, Fed Nucl Ctr, Sarov, Russia. [Glugla, M. J.] Tritium Lab, Karlsruhe, Germany. [Kanashenko, S. L.] Russian Acad Sci, Frumkin Inst Phys Chem & Electrochem, Moscow, Russia. [Causey, R. A.] Sandia Natl Labs, Livermore, CA USA. [Hassanein, A. M.] Argonne Natl Lab, Argonne, IL 60439 USA. RP Boitsov, IE (reprint author), All Russian Sci & Res Inst Expt Phys, Fed Nucl Ctr, Sarov, Russia. NR 3 TC 0 Z9 0 U1 0 U2 1 PU CONSULTANTS BUREAU/SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1068-820X J9 MATER SCI+ JI Mater. Sci. PD SEP PY 2007 VL 43 IS 5 BP 646 EP 653 DI 10.1007/s11003-008-9000-7 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 335WK UT WOS:000258324000005 ER PT J AU Lu, ZP Liu, CT AF Lu, Z. P. Liu, C. T. TI A scheme to design multi-component bulk metallic glasses in Ideal glass-forming liquids SO MATERIALS TRANSACTIONS LA English DT Article DE bulk metallic glasses; deep eutectics; heat of mixing; zirconium-copper-iron-aluminum system ID AMORPHOUS-ALLOYS; CASTING METHOD; SYSTEMS; ABILITY; YTTRIUM; ZONE; CO; TI AB In this study, we have proposed to use binary eutectics, rather than individual constituent elements, as basic units for designing complex multi-component bulk metallic glasses (BMGs), based on a novel physical concept of "ideal" glass-forming liquids. An innovative approach to designing multi-component BMGs in these ideal liquids was thus established and the reliability and usefulness of the current approach of this strategy has been confirmed in the Zr-Fe-Cu-Al metallic systems. As a result, several new BMGs with superior GFA in this system were successfully developed. C1 Univ Sci & Technol Beijing, State Key Lab Adv Met & Mat, Beijing 100083, Peoples R China. Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. RP Lu, ZP (reprint author), Univ Sci & Technol Beijing, State Key Lab Adv Met & Mat, Beijing 100083, Peoples R China. EM luzp@skl.ustb.edu.cn RI Lu, Zhao-Ping/A-2718-2009 NR 28 TC 4 Z9 4 U1 1 U2 8 PU JAPAN INST METALS PI SENDAI PA 1-14-32, ICHIBANCHO, AOBA-KU, SENDAI, 980-8544, JAPAN SN 1345-9678 EI 1347-5320 J9 MATER TRANS JI Mater. Trans. PD SEP PY 2007 VL 48 IS 9 BP 2476 EP 2482 DI 10.2320/matertrans.MJ200762 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 220ZH UT WOS:000250195500044 ER PT J AU Lee, CS Kim, SG Ahn, SH DeJonghe, LC Thomas, G AF Lee, Caroline S. Kim, Sung-Geun Ahn, Sung-Hoon DeJonghe, Lutgard C. Thomas, Gareth TI Three dimensional analysis of thermal stress and prediction of failure of polytypoidally joined Si3N4-Al2O3 functionally graded material (FGM) SO MATERIALS TRANSACTIONS LA English DT Article DE functionally grade material; finite element analysis; sialon; silicon nitride; polytypoid ID SYSTEM AB Three-dimensional analysis methods to calculate residual stress for functionally graded material (FGM) sample using sialon polytypoids to join silicon nitride and Alumina are introduced in this paper. The various multilayered FGM samples with 3, 9, and 20 layers were sintered to fabricate a crack-free joining of heterogeneous ceramics. To calculate three-dimensional thermal stresses of those fabricated FGM samples, a finite element analysis tool, ALGOR, was used. The Von Mises failure criterion and the maximum stress criterion were applied to predict failures in the FGM samples. For each case, calculated strength of each FGM layer by rule of mixture was compared with predicted thermal residual stresses. The Von Mises failure criterion predicted the locations of cracks more precisely than the maximum stress criterion. Such analyses are especially useful for graded FGM samples where the residual stresses are very difficult to measure experimentally. C1 Hanyang Univ, Div Mat & Chem Engn, Kyonggi Do, South Korea. Seoul Natl Univ, Inst Adv Machinery & Design, Sch Mech & Aerosp Engn, Seoul, South Korea. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. RP Ahn, SH (reprint author), Hanyang Univ, Div Mat & Chem Engn, Kyonggi Do, South Korea. EM ahnsh@snu.ac.kr NR 12 TC 3 Z9 3 U1 0 U2 4 PU JAPAN INST METALS PI SENDAI PA 1-14-32, ICHIBANCHO, AOBA-KU, SENDAI, 980-8544, JAPAN SN 1345-9678 EI 1347-5320 J9 MATER TRANS JI Mater. Trans. PD SEP PY 2007 VL 48 IS 9 BP 2489 EP 2493 DI 10.2320/matertrans.MRA2007092 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 220ZH UT WOS:000250195500046 ER PT J AU Parks, ML Romero, LA AF Parks, Michael L. Romero, Louis A. TI Taylor-Aris dispersion in high aspect ratio columns of nearly rectangular cross section SO MATHEMATICAL AND COMPUTER MODELLING LA English DT Article DE Taylor-Aris dispersion; gas chromatography; high aspect ratio; end effects ID PRESSURE-DRIVEN; CONDUITS; CHANNELS; SOLUTE; FLOW AB We consider Taylor-Aris dispersion in columns of nearly rectangular cross section of large aspect ratio. We generalize the results of [P.C. Chatwin, P.J. Sullivan, The effect of aspect ratio on longitudinal diffusivity in rectangular channels, J. Fluid Mech. 120 (1982) 347-358] and [M.R. Doshi, P.M. Daiyai, W.N. Gill, Three dimensional laminar dispersion in open and closed rectangular conduits, Chem. Eng. Sci. 33 (1978) 795-804] who showed that the effective diffusion rate for perfectly rectangular cross sections is remarkably different than the diffusion rate between two parallel plates - as the aspect ratio goes to infinity, the effective diffusion rate does not approach the effective diffusion rate for two parallel plates. In particular, we examine columns of nearly rectangular cross section having both non-parallel walls and asymmetric ends of arbitrary shape. In particular, this includes geometries common to microfabricated gas chromatography columns. We develop an expression for the effective diffusivity showing the contributions from the walls and the ends, and the relative importance of each. We also discuss the large effect that a small nonuniformity in the middle of the cross section can have on the effective diffusion rate, and how the ends of the cross section can be modified to control the effective diffusion rate. (C) 2006 Elsevier Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Romero, LA (reprint author), Sandia Natl Labs, POB 5800,MS 1320, Albuquerque, NM 87185 USA. EM mlparks@sandia.gov; lromero@sandia.gov RI Parks, Michael/A-2878-2008 NR 19 TC 8 Z9 8 U1 1 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0895-7177 J9 MATH COMPUT MODEL JI Math. Comput. Model. PD SEP PY 2007 VL 46 IS 5-6 BP 699 EP 717 DI 10.1016/j.mcm.2006.11.029 PG 19 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA 187BY UT WOS:000247823500010 ER PT J AU Munson, T AF Munson, Todd TI Mesh shape-quality optimization using the inverse mean-ratio metric SO MATHEMATICAL PROGRAMMING LA English DT Article ID INTERIOR-POINT ALGORITHM; CONDITION NUMBER; JACOBIAN MATRIX; IMPROVEMENT; QUANTITIES; FRAMEWORK; NORM AB Meshes containing elements with bad quality can result in poorly conditioned systems of equations that must be solved when using a discretization method, such as the finite-element method, for solving a partial differential equation. Moreover, such meshes can lead to poor accuracy in the approximate solution computed. In this paper, we present a nonlinear fractional program that relocates the vertex coordinates of a given mesh to optimize the average element shape quality as measured by the inverse mean-ratio metric. To solve the resulting large-scale optimization problems, we apply an efficient implementation of an inexact Newton algorithm that uses the conjugate gradient method with a block Jacobi preconditioner to compute the direction. We show that the block Jacobi preconditioner is positive definite by proving a general theorem concerning the convexity of fractional functions, applying this result to components of the inverse mean-ratio metric, and showing that each block in the preconditioner is invertible. Numerical results obtained with this special-purpose code on several test meshes are presented and used to quantify the impact on solution time and memory requirements of using a modeling language and general-purpose algorithm to solve these problems. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Munson, T (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM tmunson@mcs.anl.gov NR 45 TC 22 Z9 25 U1 1 U2 5 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0025-5610 J9 MATH PROGRAM JI Math. Program. PD SEP PY 2007 VL 110 IS 3 BP 561 EP 590 DI 10.1007/s10107-006-0014-3 PG 30 WC Computer Science, Software Engineering; Operations Research & Management Science; Mathematics, Applied SC Computer Science; Operations Research & Management Science; Mathematics GA 180SV UT WOS:000247387100006 ER PT J AU Perricone, MJ Anderson, TD Robino, CV Dupont, JN Michael, JR AF Perricone, M. J. Anderson, T. D. Robino, C. V. Dupont, J. N. Michael, J. R. TI Effect of composition on the formation of sigma during single-pass welding of Mo-bearing stainless steels SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID HIGH-TEMPERATURE EXPOSURE; MICROSTRUCTURAL STABILITY; PHASE-TRANSFORMATIONS; CORROSION-RESISTANCE; PITTING CORROSION; DELTA-FERRITE; SOLIDIFICATION; PRECIPITATION; METAL; BEHAVIOR AB A series of 64 Mo-bearing stainless steel compositions ranging from 0 to 10 wt pet Mo and over a broad range of Ni and Cr contents were analyzed over a variety of cooling rates. Alloys were created using the arc button melting process, and laser welds were prepared on each alloy at constant power and travel speeds ranging from 4.2 to 42 mm/s. The presence of the sigma-sigma intermetallic was observed in several primary gamma-austenite alloys with Mo contents >= 2.5 wt pet Mo and in several primary delta-ferrite alloys with Mo contents >= 6 wt pct Mo. However, its formation cannot be explained by the eutectic solidification reaction previously explored in this class of materials by the present authors. Instead, a-sigma was determined to form by the eutectoid decomposition of delta-ferrite (delta -> gamma + sigma) in the as-solidified arc melt buttons in both primary gamma-austenite and primary delta-ferrite alloys. The high cooling rates in the laser welds (estimated to range from 10(4) degrees C/S to 10(5) degrees C/S) largely prevented this transformation from occurring, resulting in the retention of metastable delta-ferrite to room temperature. A correlation was observed between the composition of the delta-ferrite in the microstructure and the calculated onset temperature of sigma stability. By combining multicomponent liquidus projections and isothermal sections, a good correlation of delta-ferrite compositions that decompose to gamma-austenite + sigma-sigma upon cooling is presented. It is suggested that the absence of the chi (chi) phase, often observed in a similar composition range at high Mo contents, could be attributed to the extremely low carbon content in these alloys. C1 Sandia Natl Labs, Joining & Coatings Div, Albuquerque, NM 87185 USA. Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. RP Perricone, MJ (reprint author), Sandia Natl Labs, Joining & Coatings Div, POB 5800, Albuquerque, NM 87185 USA. EM mperricone@rjlg.com NR 76 TC 5 Z9 6 U1 1 U2 8 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 2007 VL 38A IS 9 BP 1976 EP 1990 DI 10.1007/s11661-007-9158-x PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 211QR UT WOS:000249538900014 ER PT J AU Lassila, DH Leblanc, MM Florando, JN AF Lassila, D. H. Leblanc, M. M. Florando, J. N. TI Zinc single-crystal deformation experiments using a "6 degrees of freedom" apparatus SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID ALUMINUM; DISTORTION; ALLOYS AB A new experimental technique to study crystallographic slip system activity in metallic single crystals deformed under a condition of uniaxial stress is applied to study the behavior of Zn single crystals. The experimental apparatus promotes unconstrained shape change of inherently anisotropic materials under a condition of uniaxial stress by allowing three translational and three rotational degrees of freedom during compression; hence, we have named the experiment "6 degrees of freedom" (6DOF). The experiments also use a three-dimensional (3-D) digital image correlation (IC) system to measure full-field displacements, which are used to calculate strain and make direct observations of slip system activity. We show that the experimental results associated with a pristine zinc single crystal are precisely consistent with the theoretical predicted shape change (sample distortion) assuming that the most favored slip system on the basal plane is the only one that is active. Another experiment was performed on a processed and annealed Zn single crystal to investigate slip that is inconsistent with the critical resolved shear stress (CRSS) theory. These experiments on zinc illustrate the ability of the 6DOF experiment, together with image correlation (IC) data, to measure slip system activity with a high degree of fidelity. C1 Lawrence Livermore Natl Lab, Engn Technol Engn Div, Livermore, CA 94550 USA. RP Lassila, DH (reprint author), Lawrence Livermore Natl Lab, Engn Technol Engn Div, Livermore, CA 94550 USA. EM lassila1@llnl.gov NR 22 TC 2 Z9 2 U1 3 U2 6 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 2007 VL 38A IS 9 BP 2024 EP 2032 DI 10.1007/s11661-007-9202-x PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 211QR UT WOS:000249538900019 ER PT J AU Bahr, D Moody, N Lucas, J AF Bahr, David Moody, Neville Lucas, James TI Deformation and fracture from nano to macro: Honoring W.W. Gerberich's 70th birthday - Foreword SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Editorial Material C1 Washington State Univ, Pullman, WA 99164 USA. Sandia Natl Labs, Livermore, CA USA. Michigan State Univ, E Lansing, MI 48824 USA. RP Bahr, D (reprint author), Washington State Univ, Pullman, WA 99164 USA. RI Bahr, David/A-6521-2012 OI Bahr, David/0000-0003-2893-967X NR 0 TC 0 Z9 0 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 2007 VL 38A IS 13 BP 2153 EP 2153 DI 10.1007/s11661-007-9313-4 PG 1 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 213OM UT WOS:000249677000001 ER PT J AU Cordill, MJ Hallman, DM Moody, NR Adams, DP Gerberich, WW AF Cordill, M. J. Hallman, D. M. Moody, N. R. Adams, D. P. Gerberich, W. W. TI Thickness effects on the plasticity of gold films SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Annual Meeting of the Minerals-Metals-and-Materials-Society CY 2006 CL San Antonio, TX SP Minerals Metals Materials Soc ID INDENTATION; STRAIN; HARDNESS AB An indentation size effect is a common occurrence during nanoindentation. Thin and thick gold films, deposited using sputter deposition and evaporation, illustrate this at depths less than 100 nm. The indentation size effect, however, has been observed to be independent of film thickness. It has been modeled using a combination of an indentation size effect model and a parabolic hardening model. At the near surface regime, the indentation size effect model is dominant, and at larger depths, the parabolic hardening model is dominant, taking into effect the film thickness. The described model, which is a combination of these two, fits the experimental data for the sputter-deposited films and the evaporated films. C1 Univ Minnesota, Chem Engn & Mat Sci Dept, Minneapolis, MN 55455 USA. MTS Syst, Eden Prairie, MN USA. Sandia Natl Labs, Livermore, CA 94550 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cordill, MJ (reprint author), Univ Minnesota, Chem Engn & Mat Sci Dept, Minneapolis, MN 55455 USA. EM cordill@cems.umn.edu OI Cordill, Megan/0000-0003-1142-8312 NR 14 TC 5 Z9 5 U1 0 U2 4 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 2007 VL 38A IS 13 BP 2154 EP 2159 DI 10.1007/s11661-006-9011-7 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 213OM UT WOS:000249677000002 ER PT J AU Steward, RV Wang, G Buchanan, RA Liaw, PK Saleh, TA Klarstrom, DL Meck, SN AF Steward, R. V. Wang, G. Buchanan, R. A. Liaw, P. K. Saleh, T. A. Klarstrom, D. L. Meck, S. N. TI In-situ electrochemical investigations of a nickel-based alloy subjected to fatigue SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Annual Meeting of the Minerals-Metals-and-Materials-Society CY 2006 CL San Antonio, TX SP Minerals Metals Materials Soc ID CORROSION-FATIGUE; CRACK INITIATION; CHROMIUM STEELS; STAINLESS-STEEL; BEHAVIOR; MODEL AB The HASTELLOY C2000 superalloy is a commercially designed superalloy manufactured to function in reducing and oxidizing corrosive solutions. The industrial applications have tremendous potential in automotive, structural, aviation, and storage components. Although C2000 demonstrates good reducing and oxidizing traits in extremely aggressive media (which are attractive features of its chemistry), changes in the mechanical properties are believed to be insignificant due to its strong propensity to passivate under corrosive conditions. The ductility behavior and corrosion properties of C2000 are superior to those of stainless steels. The objective of the present study is to examine the corrosion-fatigue behavior of C2000 in a 3.5 wt pct sodium-chloride (NaCl) solution. C2000 submerged in 3.5 wt pct NaCl at room temperature is not susceptible to localized corrosion, such as pitting, during fatigue. At an accelerated potential of 350 mV, the current responses show an increase in the current due to slip steps emerging to the surface as a result of fatigue. The crack-initiation site and the examination of the fracture morphology are discussed. C1 Univ Tennessee, Dept Mat Sci & Engn, Res Dev & Manufacturing, Sugar Land, TX USA. Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. Los Alamos Natl Lab, Los Alamos, NM USA. Haynes Int Inc, Res & Dev, Kokomo, IN 46904 USA. RP Steward, RV (reprint author), Univ Tennessee, Dept Mat Sci & Engn, Res Dev & Manufacturing, Sugar Land, TX USA. EM rsteward@slb.com RI Wang, Gongyao/C-4003-2011; OI Saleh, Tarik/0000-0003-2108-4293 NR 17 TC 1 Z9 1 U1 0 U2 12 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 2007 VL 38A IS 13 BP 2226 EP 2234 DI 10.1007/s11661-007-9231-5 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 213OM UT WOS:000249677000009 ER PT J AU Kennedy, MS Bahr, DF Moody, NR AF Kennedy, M. S. Bahr, D. F. Moody, N. R. TI The effect of nonuniform chemistry on interfacial fracture toughness SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Annual Meeting of the Minerals-Metals-and-Materials-Society CY 2006 CL San Antonio, TX SP Minerals Metals Materials Soc ID THIN-FILM ADHESION; SYSTEMS; GROWTH; COPPER AB The adhesion of metallic-ceramic interfaces is generally ascribed to the mixture of several mechanisms, including chemical bonding, texture, strain transfer, and plasticity. This study examines the impact of alterations in chemical bonding along an interface on the nanometer scale on the interfacial fracture energy. Using a well-characterized system of W/SiO2, small areas of the interface were masked with polymer tubes to prohibit the area from adhering well to the W film. This showed that the interfacial fracture energy was proportional to the area of higher adhesion. This finding was then used to study the growth of a Ti interlayer used for adhesion promotion in a Pt/SiO2 system. Because the adhesion energy slowly grew from values near the Pt/SiO2 to values typical of Ti/SiO2, the growth mechanism for DC magnetron sputtering of thin film Ti on SiO2 was inferred to be island growth instead of layer-by-layer growth. C1 Washington State Univ, Sch Mech & Mat Engn, Pullman, WA 99164 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Kennedy, MS (reprint author), Washington State Univ, Sch Mech & Mat Engn, Pullman, WA 99164 USA. EM kennedy2@mail.wsu.edu RI Bahr, David/A-6521-2012 OI Bahr, David/0000-0003-2893-967X NR 26 TC 4 Z9 4 U1 2 U2 4 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 2007 VL 38A IS 13 BP 2256 EP 2262 DI 10.1007/s11661-006-9082-5 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 213OM UT WOS:000249677000013 ER PT J AU Wu, L Stoica, GM Liao, HH Agnew, SR Payzant, EA Wang, GY Fielden, DE Chen, L Liaw, PK AF Wu, Liang Stoica, Grigoreta M. Liao, Hao-Hsiang Agnew, Sean R. Payzant, E. Andrew Wang, Gongyao Fielden, Douglas E. Chen, Lijia Liaw, Peter K. TI Fatigue-property enhancement of magnesium alloy, AZ31B, through equal-channel-angular pressing SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Annual Meeting of the Minerals-Metals-and-Materials-Society CY 2006 CL San Antonio, TX SP Minerals Metals Materials Soc ID SEVERE PLASTIC-DEFORMATION; TEXTURE EVOLUTION; EXTRUSION; DUCTILITY AB The fatigue behavior of magnesium-alloy, AZ31B, prestrained by equal-channel-angular pressing (ECAP) was studied as a function of the accumulated plastic-strain level and the orientation of the samples (along and perpendicular to the ECAP pressing direction). The material was processed via route B-C, at 200 degrees C, for 1, 2, and 8 passes, with and without a back pressure (BP) applied on the billet during ECAP. The low-cycle fatigue behavior of the AZ31B alloy is shown to be anisotropic and texture dependent. Due to the initial texture orientation, the specimens loaded parallel to the ECAP pressing direction have a longer fatigue life than the samples loaded perpendicular to it. The low-cycle fatigue life of the AZ31B alloy is enhanced by ECAP. The fatigue-property improvement is discussed in light of the grain-size refinement, enhanced ductility, and texture evolution. C1 Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22904 USA. Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. Shenyang Univ Technol, Sch Mat Sci & Engn, Shenyang, Peoples R China. RP Wu, L (reprint author), Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. EM LWU7@utk.edu RI Payzant, Edward/B-5449-2009; Wang, Gongyao/C-4003-2011 OI Payzant, Edward/0000-0002-3447-2060; NR 21 TC 18 Z9 19 U1 1 U2 9 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 2007 VL 38A IS 13 BP 2283 EP 2289 DI 10.1007/s11661-007-9123-8 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 213OM UT WOS:000249677000016 ER PT J AU Yang, Y Allameh, S Lou, J Imasogie, B Boyce, BL Soboyejo, WO AF Yang, Y. Allameh, S. Lou, J. Imasogie, B. Boyce, B. L. Soboyejo, W. O. TI Fatigue of LIGA Ni micro-electro-mechanical system thin films SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID POLYSILICON MEMS STRUCTURES; HIGH-ASPECT-RATIO; MECHANICAL-PROPERTIES; NICKEL; MICROSTRUCTURES; EVOLUTION; GAUGE AB This article presents the results of an experimental study of the mechanisms of fatigue in 270-mu m-thick LIGA (lithographic, galvanoformung, abformung) Ni micro-electro-mechanical systems (MEMS) thin films with columnar microstructure. Stress-life behavior is compared with the previously reported data for LIGA Ni MEMS films and bulk Ni. The LIGA Ni thin films are shown to have comparable fatigue lives to bulk annealed Ni. The underlying mechanisms of fatigue crack growth are elucidated rig scanning electron and focused ion beam (FIB) microscopy. Stress-driven recrystallization was revealed near the fatigue crack-tip using FIB microscopy. Microvoids were also found to form and coalesce in the recrystallized grains. This led to subsequent fatigue crack growth at the microscopic and macroscopic scales. The crack profiles revealed that fatigue crack growth was retarded by crack deflection and branching. The implications of the results are then discussed for the analyses of fatigue in nickel MEMS structures. C1 Princeton Inst Sci & Technol Mat, Princeton, NY USA. Princeton Univ, Dept Mech & Aerosp Engn, Princeton, NJ 08544 USA. No Kentucky Univ Lib, Dept Phys Geol, Highland Hts, KY 41099 USA. Rice Univ, Dept Mech Engn & Mat Sci, Houston, TX 77005 USA. Obafemi Awolowo Univ, Dept Met Engn & Mat Sci, Ife 220005, Nigeria. Sandia Natl Labs, Mat Proc Sci Ctr, Albuquerque, NM 87185 USA. RP Yang, Y (reprint author), Princeton Inst Sci & Technol Mat, Princeton, NY USA. EM soboyej@princeton.edu RI Boyce, Brad/H-5045-2012; Yang, Yong/G-9148-2011 OI Boyce, Brad/0000-0001-5994-1743; Yang, Yong/0000-0002-0491-8295 NR 50 TC 6 Z9 6 U1 1 U2 14 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD SEP PY 2007 VL 38A IS 13 BP 2340 EP 2348 DI 10.1007/s11661-007-9246-y PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 213OM UT WOS:000249677000022 ER PT J AU Bernardini, S Ishii, M Whittaker, E Hamilton, B Freeland, JW Poolton, NRJ De Gendt, S AF Bernardini, S. Ishii, M. Whittaker, E. Hamilton, B. Freeland, J. W. Poolton, N. R. J. De Gendt, S. TI Nanoscale imaging and X-ray spectroscopy of electrically active defects in ultra thin dielectrics on silicon SO MICROELECTRONIC ENGINEERING LA English DT Article; Proceedings Paper CT 15th Biennial Conference on Insulating Films on Semiconductors CY JUN 20-23, 2007 CL Glyfada Athens, GREECE SP IBM, Natl Ctr Sci Res Demokritos, Univ Athens, Natl Tech, Univ Ioannina, IEEE, Electron Devices Soc DE high K; atomic force microscopy; electric force microscopy; x-ray; synchrotron; photoionization; charge localization; local chemistry; x-ray absorption spectra ID FORCE MICROSCOPY AB This work concerns deeply bound charge centers in ultra thin high-k films. Non-contact Atomic Force Microscopy was used to simultaneously image topology and electric force data arising from unscreened fixed charges. These charges were produced using synchrotron radiation to pump Si L and K shell transitions. Defect charging then results from electron transfer between a defect state and a core hole state. We were able to demonstrate the local detection of x-ray absorption spectra using the probe tip. This enabled us to establish a possible link between film morphology, electronic defects and local stoichiometry in ultra thin high-k films on the nm scale. C1 Univ Manchester, Sch Elect & Elect Engn, Manchester M60 1QD, Lancs, England. NIMS, Tsukuba, Ibaraki 3050044, Japan. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Daresbury Lab, Synchrotron Radiat Dept, Warrington WA4 4AD, Cheshire, England. IMEC, B-3001 Louvain, Belgium. RP Hamilton, B (reprint author), Univ Manchester, Sch Elect & Elect Engn, Sackville St Bldg,POB 88, Manchester M60 1QD, Lancs, England. EM b.hamilton@manchester.ac.uk RI Hamilton, Bruce/H-2179-2011; BERNARDINI, Sandrine/D-3185-2012 OI BERNARDINI, Sandrine/0000-0001-9673-222X NR 8 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9317 J9 MICROELECTRON ENG JI Microelectron. Eng. PD SEP-OCT PY 2007 VL 84 IS 9-10 BP 2286 EP 2289 DI 10.1016/j.mee.2007.04.054 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Optics; Physics, Applied SC Engineering; Science & Technology - Other Topics; Optics; Physics GA 180PS UT WOS:000247378600104 ER PT J AU Tsetseris, L Fleetwood, DM Schrimpf, RD Zhou, XJ Batyrev, IG Pantelides, ST AF Tsetseris, L. Fleetwood, D. M. Schrimpf, R. D. Zhou, X. J. Batyrev, I. G. Pantelides, S. T. TI Hydrogen effects in MOS devices SO MICROELECTRONIC ENGINEERING LA English DT Article; Proceedings Paper CT 15th Biennial Conference on Insulating Films on Semiconductors CY JUN 20-23, 2007 CL Glyfada Athens, GREECE SP IBM, Natl Ctr Sci Res Demokritos, Univ Athens, Natl Tech, Univ Ioannina, IEEE, Electron Devices Soc DE hydrogen; first principles; bias temperature instability; interface; SiO2; metal gate; nanotubes; embedment ID BIAS TEMPERATURE INSTABILITY; DOSE-RATE SENSITIVITY; NEGATIVE BIAS; GATE DIELECTRICS; SILICON; SIO2; SEMICONDUCTORS; TRANSISTORS; DIFFUSION; INTERFACE AB Hydrogen has a dual effect in metal-oxide-semiconductor (MOS) devices, leading to improvement or degradation of their characteristics in many ways. Here, we present a review of results from first-principles calculations on key processes involving hydrogen in devices. We describe H reactions at the Si-SiO2 interface that create or annihilate carrier traps and various mechanisms of H trapping and release in the gate oxide, the substrate or the metal gate of a device. Our findings account for key features of well-known reliability phenomena, for example bias-temperature instability. We finally discuss the role of hydrogen in building devices with embedded carbon nanotubes. C1 Vanderbilt Univ, Nashville, TN USA. Aristotle Univ Thessaloniki, GR-54214 Thessaloniki, Greece. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Tsetseris, L (reprint author), Vanderbilt Univ, 221 Kirkland Hall, Nashville, TN USA. EM leonidas.tsetseris@vanderbilt.edu RI Schrimpf, Ronald/L-5549-2013 OI Schrimpf, Ronald/0000-0001-7419-2701 NR 29 TC 30 Z9 30 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9317 J9 MICROELECTRON ENG JI Microelectron. Eng. PD SEP-OCT PY 2007 VL 84 IS 9-10 BP 2344 EP 2349 DI 10.1016/j.mee.2007.04.076 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Optics; Physics, Applied SC Engineering; Science & Technology - Other Topics; Optics; Physics GA 180PS UT WOS:000247378600118 ER PT J AU Tanner, DM Parson, TB Corwin, AD Walraven, JA Wittwer, JW Boyce, BL Winzer, SR AF Tanner, D. M. Parson, T. B. Corwin, A. D. Walraven, J. A. Wittwer, J. W. Boyce, B. L. Winzer, S. R. TI Science-based MEMS reliability methodology SO MICROELECTRONICS RELIABILITY LA English DT Article; Proceedings Paper CT 18th European Symposium on Reliability of Electron Devices, Failure Physics and Analysis CY 2007 CL Arcachon, FRANCE SP IEEE Electron Devices Soc, EEE Reliabil Soc ID POLYCRYSTALLINE SILICON; FAILURE; LAYER AB In cases where device numbers are limited, large statistical studies to verify reliability are impractical. Instead, an approach incorporating a solid base of modelling, simulation, and material science into a standard reliability methodology makes more sense and leads to a science-based reliability methodology. The basic reliability method is (a) design, model and fabricate, (b) test structures and devices, (c) identify failure modes and mechanisms, (d) develop predictive reliability models (accelerated aging), and (e) develop qualification methods. At various points in these steps technical data is required on MEMS material properties (residual stress, fracture strength, fatigue, etc.), MEMS surface characterizabon (stiction, friction, adhesion, role of coatings, etc.) or MEMS modelling and simulation (finite element, analysis, uncertainty analysis, etc.). This methodology is discussed as it relates to reliability testing of a micro-mirror array consisting of 144-piston mirrors. In this case, 140 mirrors were cycled full stroke (1.5 mu m) 26 billion times with no failure. Using our technical science base, fatigue of the springs was eliminated as a mechanism of concern. Eliminating this wear-out mechanism allowed use of the exponential statistical model to predict lower bound confidence levels for failure rate in a "no-fail" condition. (C) 2007 Elsevier Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Lockheed Martin Corp, ATC, Palo Alto, CA 94304 USA. RP Tanner, DM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM tannerdm@sandia.gov RI Boyce, Brad/H-5045-2012 OI Boyce, Brad/0000-0001-5994-1743 NR 16 TC 15 Z9 17 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0026-2714 J9 MICROELECTRON RELIAB JI Microelectron. Reliab. PD SEP-NOV PY 2007 VL 47 IS 9-11 SI SI BP 1806 EP 1811 DI 10.1016/j.microrel.2007.07.061 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 226QW UT WOS:000250604600094 ER PT J AU Arsenlis, A Cai, W Tang, M Rhee, M Oppelstrup, T Hommes, G Pierce, TG Bulatov, VV AF Arsenlis, A. Cai, W. Tang, M. Rhee, M. Oppelstrup, T. Hommes, G. Pierce, T. G. Bulatov, V. V. TI Enabling strain hardening simulations with dislocation dynamics SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID PLASTIC-DEFORMATION; ELASTIC FIELD; FREE-SURFACE; FCC METALS; CRYSTALS AB Numerical algorithms for discrete dislocation dynamics simulations are investigated for the purpose of enabling strain hardening simulations of single crystals on massively parallel computers. The algorithms investigated include the O(N) calculation of forces, the equations of motion, time integration, adaptive mesh refinement, the treatment of dislocation core reactions and the dynamic distribution of data and work on parallel computers. A simulation integrating all these algorithmic elements using the Parallel Dislocation Simulator (ParaDiS) code is performed to understand their behaviour in concert and to evaluate the overall numerical performance of dislocation dynamics simulations and their ability to accumulate percent of plastic strain. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Stanford Univ, Dept Mech Engn, Stanford, CA 94305 USA. RP Arsenlis, A (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. EM arsenlis@llnl.gov OI Cai, Wei/0000-0001-5919-8734 NR 34 TC 160 Z9 161 U1 1 U2 47 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD SEP PY 2007 VL 15 IS 6 BP 553 EP 595 DI 10.1088/0965-0393/15/6/001 PG 43 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 209MO UT WOS:000249392800001 ER PT J AU Wang, ZQ Beyerlein, IJ Lesar, R AF Wang, Z. Q. Beyerlein, I. J. Lesar, R. TI The importance of cross-slip in high-rate deformation SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID 3D DISLOCATION DYNAMICS; EXTENDED DISLOCATIONS; ELASTIC FIELD; FCC METALS; STRESS; MOTION; SIMULATIONS; DEPENDENCE; CRYSTALS; VELOCITY AB We apply three-dimensional dislocation dynamics simulations to study the dynamic response of materials at high strain rates ( 104 to 106 s(-1)) with the focus on investigating the role of cross-slip in deformation. By comparing simulations with and without cross-slip, we find that cross-slip plays a role in the generation and annihilation of dislocations, leading to different dislocation velocities, density evolution and macroscale plastic response. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Wang, ZQ (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI LeSar, Richard/G-1609-2012; Beyerlein, Irene/A-4676-2011 NR 29 TC 34 Z9 34 U1 0 U2 12 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 EI 1361-651X J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD SEP PY 2007 VL 15 IS 6 BP 675 EP 690 DI 10.1088/0965-0393/15/6/006 PG 16 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 209MO UT WOS:000249392800006 ER PT J AU Fried, M Hixson, KK Anderson, L Ogata, Y Mutabingwa, TK Duffy, PE AF Fried, Michal Hixson, Kim K. Anderson, Lori Ogata, Yuko Mutabingwa, Theonest K. Duffy, Patrick E. TI The distinct proteome of placental malaria parasites SO MOLECULAR AND BIOCHEMICAL PARASITOLOGY LA English DT Article DE placental malaria; plastmodium falciparum; membrane-associated proteins; comparative proteomic ID CHONDROITIN SULFATE-A; PREGNANCY-ASSOCIATED MALARIA; PLASMODIUM-FALCIPARUM; INFECTED ERYTHROCYTES; ACCURATE MASS; TAG STRATEGY; GENE FAMILY; PROTEINS; EXPRESSION; VAR2CSA AB Malaria proteins expressed on the surface of Plasmodium falciparum infected erythrocytes (IE) mediate adhesion and are targeted by protective immune responses. During pregnancy, IE sequester in the placenta. Placental IE bind to the molecule chondroitin sulfate A (CSA) and preferentially transcribe the gene that encodes VAR2CSA, a member of the PfEMP1 variant surface antigen family. Over successive pregnancies women develop specific immunity to CSA-binding IE and antibodies to VAR2CSA. We used tandem mass spectrometry together with accurate mass and time tag technology to study IE membrane fractions of placental parasites. VAR2CSA pepticles were detected in placental IE and in IE from children, but the MC variant of VAR2CSA was specifically associated with placental IE. We identified six conserved hypothetical proteins with putative TM or signal peptides that were exclusively expressed by the placental IE, and 11 such proteins that were significantly more abundant in placental IE. One of these hypothetical proteins, PHI 1785w, is a 42 kDa molecule detected by Western blot in parasites infecting pregnant women but not those infecting children. (C) 2007 Elsevier B.V. All rights reserved. C1 Seattle Biomed Res Inst, Seattle, WA 98109 USA. Univ Washington, Seattle, WA 98195 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA USA. Natl Inst Med Res, Dar Es Salaam, Tanzania. RP Fried, M (reprint author), Seattle Biomed Res Inst, 4 Nickerson St,307 W Lake Ave N, Suite 500, Seattle, WA 98109 USA. EM michal.fried@sbri.org FU NIAID NIH HHS [AI52059] NR 34 TC 38 Z9 40 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-6851 J9 MOL BIOCHEM PARASIT JI Mol. Biochem. Parasitol. PD SEP PY 2007 VL 155 IS 1 BP 57 EP 65 DI 10.1016/j.molbiopara.2007.05.010 PG 9 WC Biochemistry & Molecular Biology; Parasitology SC Biochemistry & Molecular Biology; Parasitology GA 200CX UT WOS:000248742600007 PM 17618698 ER PT J AU Tsyusko, OV Peters, MB Hagen, C Tuberville, TD Mousseau, TA Moller, AP Glenn, TC AF Tsyusko, Olga V. Peters, Maureen B. Hagen, Cris Tuberville, Tracey D. Mousseau, Timothy A. Moller, Anders P. Glenn, Travis C. TI Microsatellite markers isolated from barn swallows (Hirundo rustica) SO MOLECULAR ECOLOGY NOTES LA English DT Article DE Hirundo rustica; microsatellites; mutation; PCR; primer; radiation ID AMPLIFICATION; LOCI AB Fifteen polymorphic microsatellite DNA loci were isolated from barn swallow (Hirundo rustica) and optimized for future studies of radiation-induced mutations in populations from Ukraine. The loci were screened for variability among 25 individuals from two populations. The primers amplified loci with relatively high numbers of alleles ranging from five to 32 alleles per locus and polymorphic information content from 0.481 to 0.951. Observed heterozygosity varied from 0.458 to 0.960. None of the loci showed deviations from Hardy-Weinberg equilibrium in either population. C1 Univ Georgia, Savannah River Ecol Lab, Inst Ecol, Aiken, SC 29802 USA. Univ S Carolina, Dept Biol Sci, Columbia, SC 29802 USA. Univ Paris 06, Lab Parasitol Evolut, FR-75252 Paris, France. RP Tsyusko, OV (reprint author), Univ Georgia, Savannah River Ecol Lab, Inst Ecol, PO Drawer E, Aiken, SC 29802 USA. EM tsyusko@srel.edu RI Glenn, Travis/A-2390-2008; OI Tsyusko, Olga/0000-0001-8196-1062 NR 8 TC 11 Z9 11 U1 0 U2 6 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 1471-8278 J9 MOL ECOL NOTES JI Mol. Ecol. Notes PD SEP PY 2007 VL 7 IS 5 BP 833 EP 835 DI 10.1111/j.1471-8286.2007.01719.x PG 3 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 206OO UT WOS:000249193000027 ER PT J AU Peters, MB Glenn, JL Svete, P Hagen, C Tsyusko, OV Decoursey, P Lieutenant-Gosselin, M Garant, D Glenn, TC AF Peters, Maureen B. Glenn, Julie L. Svete, Pam Hagen, Cris Tsyusko, Olga V. Decoursey, Patricia Lieutenant-Gosselin, Melissa Garant, Dany Glenn, Travis C. TI Development and characterization of microsatellite loci in the eastern chipmunk (Tamias striatus) SO MOLECULAR ECOLOGY NOTES LA English DT Article DE Eastern chipmunk; microsatellites; parentage analysis; PCR; population structure; Tamias striatus ID UNIVERSAL; DNA; PCR AB We isolated and characterized 16 microsatellite loci in the eastern chipmunk, Tamias striatus. The loci were screened across 25 individuals from one population and shown to be polymorphic with the number of alleles per locus ranging from two to 17. Polymorphic information content ranged from 0.212 to 0.887 and observed heterozygosity ranged from 0.200 to 0.960. Only two loci (Chip 10 and Chip 25) deviated from Hardy-Weinberg equilibrium. C1 Univ Georgia, Savannah River Ecol Lab, Inst Ecol, Aiken, SC 29802 USA. Univ S Carolina, Dept Biol Sci, Columbia, SC 29802 USA. Univ Sherbrooke, Fac Sci, Dept Biol, Sherbrooke, PQ J1K 2R1, Canada. RP Peters, MB (reprint author), Univ Georgia, Savannah River Ecol Lab, Inst Ecol, PO Drawer E, Aiken, SC 29802 USA. EM peters@srel.edu RI Glenn, Travis/A-2390-2008; Garant, Dany/D-7406-2013; OI Garant, Dany/0000-0002-8091-1044; Tsyusko, Olga/0000-0001-8196-1062 NR 8 TC 7 Z9 7 U1 0 U2 1 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 1471-8278 J9 MOL ECOL NOTES JI Mol. Ecol. Notes PD SEP PY 2007 VL 7 IS 5 BP 877 EP 879 DI 10.1111/j.1471-8286.2007.01735.x PG 3 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 206OO UT WOS:000249193000042 ER PT J AU Tsyusko, OV Peters, MB Tuberville, TD Hagen, C Eppley, SM Glenn, TC AF Tsyusko, Olga V. Peters, Maureen B. Tuberville, Tracey D. Hagen, Cris Eppley, Sarah M. Glenn, Travis C. TI Microsatellite markers isolated from saltgrass (Distichlis spicata) SO MOLECULAR ECOLOGY NOTES LA English DT Article DE breeding system; Distichlis spicata; microsatellites; mutation; PCR; primer ID SEXES; GRASS AB Twelve polymorphic microsatellite DNA loci were isolated from saltgrass (Distichlis spicata) and optimized for future studies of its breeding system. The loci were screened for variability among 24 individuals from two populations. The primers amplified loci with numbers of alleles ranging from four to 14 per locus and polymorphic information content from 0.481 to 0.951. Observed heterozygosity varied from 0.227 to 0.958. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Portland State Univ, Dept Biol, Portland, OR 97207 USA. Univ S Carolina, Dept Biol Sci, Columbia, SC 29802 USA. RP Tsyusko, OV (reprint author), Univ Georgia, Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. EM tsyusko@srel.edu RI Glenn, Travis/A-2390-2008; OI Tsyusko, Olga/0000-0001-8196-1062 NR 10 TC 0 Z9 0 U1 0 U2 2 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1471-8278 J9 MOL ECOL NOTES JI Mol. Ecol. Notes PD SEP PY 2007 VL 7 IS 5 BP 883 EP 885 DI 10.1111/j.1471-8286.2007.01737.x PG 3 WC Biochemistry & Molecular Biology; Ecology; Evolutionary Biology SC Biochemistry & Molecular Biology; Environmental Sciences & Ecology; Evolutionary Biology GA 206OO UT WOS:000249193000044 ER PT J AU Chen, B Kantowski, R Baron, E Knop, S Hauschildt, PH AF Chen, B. Kantowski, R. Baron, E. Knop, S. Hauschildt, P. H. TI Steps for solving the radiative transfer equation for arbitrary flows in stationary space-times SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE radiative transfer; relativity ID COMOVING-FRAME EQUATION; RELATIVISTIC FLOWS; TRANSPORT; COLLAPSE AB We derive the radiative transfer equation for arbitrary stationary relativistic flows in stationary space-times, i.e. for steady-state transfer problems. We show how the standard characteristics method of solution developed by Mihalas and used throughout the radiative transfer community can be adapted to multidimensional applications with isotropic sources. Because the characteristics always coincide with geodesics and can always be specified by constants, direct integration of the characteristics derived from the transfer equation as commonly done in 1D applications is not required. The characteristics are known for a specified metric from the geodesics. We give details in both flat and static spherically symmetric space-times. This work has direct application in 3D simulations of supernovae, gamma-ray bursts, and active galactic nuclei, as well as in modelling neutron star atmospheres. C1 Univ Oklahoma, Homer L Dodge Dept Phys & Astron, Norman, OK 73019 USA. Lawrence Berkeley Natl Lab, Computat Res Div, Berkeley, CA 94720 USA. Hamburger Sternwarte, D-21029 Hamburg, Germany. RP Chen, B (reprint author), Univ Oklahoma, Homer L Dodge Dept Phys & Astron, 440 W Brooks,Rm 100, Norman, OK 73019 USA. EM chen@nhn.ou.edu RI Baron, Edward/A-9041-2009; chen, bin/H-5989-2012 OI Baron, Edward/0000-0001-5393-1608; chen, bin/0000-0002-0799-2327 NR 23 TC 12 Z9 12 U1 0 U2 0 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD SEP 1 PY 2007 VL 380 IS 1 BP 104 EP 112 DI 10.1111/j.1365-2966.2007.11652.x PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 209YC UT WOS:000249422900027 ER PT J AU Panaitescu, A AF Panaitescu, A. TI Jet breaks in the X-ray light-curves of Swift gamma-ray burst afterglows SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE radiation mechanisms : non-thermal; shock waves; gamma-rays : bursts ID STRUCTURED OUTFLOWS; ENERGY INJECTION; ENERGETICS; EVOLUTION; REDSHIFT; MODELS; ERA AB In the set of 236 gamma-ray burst (GRB) afterglows observed by Swift between 2005 January and 2007 March, we identify 30 X-ray light-curves that have power-law fall-offs that exhibit a steepening ('break') at 0.1-10 d after they are triggered, to a decay steeper than t(-1.5). For most of these afterglows, the X-ray spectral slope and the decay indices before and after the break can be accommodated by the standard jet model although a different origin of the breaks cannot be ruled out. In addition, there are 27 other afterglows which have X-ray light-curves that may also exhibit a late break to a steep decay, but the evidence is not that compelling. The X-ray emissions of 38 afterglows decay slower than t(-1.5) until after 3 d, half of them exhibiting such a slow decay until after 10 d. Therefore, the fraction of well-monitored Swift afterglows with potential jet breaks is around 60 per cent, whether we count only the strongest cases for each type or all of them. This fraction is comparable to the 75 per cent of pre-Swift afterglows which have optical light-curves that displayed similar breaks at similar to 1 d. The peak energy of the GRB spectrum of Swift afterglows with light-curve breaks shows the same correlations with the burst isotropic output (Amati relation) and with the burst collimated output (Ghirlanda relation) as previously found for pre-Swift optical afterglows with light-curve breaks. However, we find that the Ghirlanda relation is largely a consequence of Amati's and that the use of the jet-break time leads to a stronger Ghirlanda correlation only when the few objects that do not satisfy the Amati relation are included. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Panaitescu, A (reprint author), Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. EM alin@lanl.gov NR 37 TC 42 Z9 42 U1 0 U2 0 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD SEP 1 PY 2007 VL 380 IS 1 BP 374 EP 380 DI 10.1111/j.1365-2966.2007.12084.x PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 209YC UT WOS:000249422900050 ER PT J AU Yoon, M Yang, SY Wang, E Zhang, ZY AF Yoon, Mina Yang, Shenyuan Wang, Enge Zhang, Zhenyu TI Charged fullerenes as high-capacity hydrogen storage media SO NANO LETTERS LA English DT Article ID WALLED CARBON NANOTUBES; AUGMENTED-WAVE METHOD; C-60; ENERGY; IONS; POLARIZABILITY; H-2 AB Using first-principles calculations within density functional theory, we explore systematically the capacity of charged carbon fullerenes C(n) (20 <= n <= 82) as hydrogen storage media. We find that the binding strength of molecular hydrogen on either positively or negatively charged fullerenes can be dramatically enhanced to 0.18-0.32 ell, a desirable range for potential room-temperature, near ambient applications. The enhanced binding is delocalized in nature, surrounding the whole surface of a charged fullerene, and is attributed to the polarization of the hydrogen molecules by the high electric field generated near the surface of the charged fullerene. At full hydrogen coverage, these charged fullerenes; can gain storage capacities of up to similar to 8.0 wt %. We also find that, contrary to intuitive expectation, fullerenes containing encapsulated metal atoms only exhibit negligible enhancement in the hydrogen binding strength, because the charge donated by the metal atoms is primarily confined inside the fullerene cages. These predictions may prove to be instrumental in searching for a new class of high-capacity hydrogen storage media. C1 Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Chinese Acad Sci, Int Ctr Quantum Struc, Inst Phys, Beijing 100080, Peoples R China. RP Yoon, M (reprint author), Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. RI Yoon, Mina/A-1965-2016 OI Yoon, Mina/0000-0002-1317-3301 NR 39 TC 131 Z9 134 U1 2 U2 26 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD SEP PY 2007 VL 7 IS 9 BP 2578 EP 2583 DI 10.1021/nl070809a PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 211CM UT WOS:000249501900007 PM 17718530 ER PT J AU Robinson, JT Ratto, F Moutanabbir, O Heun, S Locatelli, A Mentes, TO Aballe, L Dubon, OD AF Robinson, Jeremy T. Ratto, Fulvio Moutanabbir, Oussama Heun, Stefan Locatelli, Andrea Mentes, T. Onur Aballe, Lucia Dubon, Oscar D. TI Gold-catalyzed oxide nanopatterns for the directed assembly of Ge island arrays on Si SO NANO LETTERS LA English DT Article ID AU-PATTERNED SI; SEMICONDUCTOR NANOSTRUCTURES; SI(001) SURFACE; GROWTH; SILICON; INTERFACE; PYRAMIDS; METAL; TRANSITION; MICROSCOPY AB The heteroepitaxial growth of Ge on Au-patterned Si(001) is investigated using in situ spectromicroscopy. Patterning of a hydrogen-terminated Si surface with a square array of Au dots followed by brief exposure to air leads to the spontaneous, local oxidation of Si. The resulting oxide nanopattern limits the surface migration of Au during annealing up to 600 degrees C, resulting in complete preservation of the Au pattern. Subsequent deposition of Ge induces a redistribution of Au across the surface even as the oxide nanopattern persists. As a result, the oxide pattern drives the growth of Ge islands into an ordered assembly, while Au decorates the surfaces of the Ge islands and modifies their shape. C1 Univ Calif Berkeley, Dept Mat Sci & Engn, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Quebec, INRS EMT, Quebec City, PQ J3X 1S2, Canada. Keio Univ, Dept Appl Phys & Physico Informats, Kouhoku Ku, Yokohama, Kanagawa 223, Japan. CNR, INFM, Lab Nazl TASC, I-34012 Trieste, Italy. Sincrotrone Trieste, SCPA, I-34012 Trieste, Italy. Max Planck Inst Microstruct Phys, D-06120 Halle, Germany. CNR, IFM Scuola Normale Superiore Cavalieri, NEST, I-56126 Pisa, Italy. RP Dubon, OD (reprint author), Univ Calif Berkeley, Dept Mat Sci & Engn, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. EM oddubon@berkeley.edu RI Moutanabbir, Oussama/A-4001-2009; Heun, Stefan/B-4406-2011; Robinson, Jeremy/F-2748-2010 OI Mentes, Tevfik Onur/0000-0003-0413-9272; Locatelli, Andrea/0000-0002-8072-7343; Heun, Stefan/0000-0003-1989-5679; NR 32 TC 17 Z9 17 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD SEP PY 2007 VL 7 IS 9 BP 2655 EP 2659 DI 10.1021/nl071051y PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 211CM UT WOS:000249501900021 PM 17672506 ER PT J AU Tao, YF Zohar, H Olsen, BD Segalman, RA AF Tao, Yuefei Zohar, Hagar Olsen, Bradley D. Segalman, Rachel A. TI Hierarchical nanostructure control in rod-coil block copolymers with magnetic fields SO NANO LETTERS LA English DT Article ID DIBLOCK COPOLYMER; ELECTRIC-FIELDS; THIN-FILMS; ALIGNMENT; ORIENTATION; TRANSITION; MICROSTRUCTURE; PARALLEL AB Magnetic field alignment of rod-coil block copolymers is shown to proceed through coupling to the diamagnetic moment of individual rod blocks. Block copolymer self-assembly then leads to alignment of the interfaces perpendicular to the field lines and long range order on a 10 nm lengthscale. This is in contrast to previously demonstrated alignment techniques, which couple to the block copolymer interfaces rather than individual molecules. Furthermore, alignment occurs without direct physical contact to samples millimeters in size. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Segalman, RA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. EM segalman@berkeley.edu OI Segalman, Rachel/0000-0002-4292-5103; Olsen, Bradley/0000-0002-7272-7140 NR 26 TC 54 Z9 55 U1 3 U2 31 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD SEP PY 2007 VL 7 IS 9 BP 2742 EP 2746 DI 10.1021/nl0712320 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 211CM UT WOS:000249501900036 PM 17683154 ER PT J AU Yerushalmi, R Ho, JC Jacobson, ZA Javey, A AF Yerushalmi, Roie Ho, Johnny C. Jacobson, Zachery A. Javey, Ali TI Generic nanomaterial positioning by carrier and stationary phase design SO NANO LETTERS LA English DT Article ID WALLED CARBON NANOTUBES; METAL NANOPARTICLES; BLOCK-COPOLYMERS; FORCE MICROSCOPY; AQUEOUS-MEDIA; ADSORPTION; PARTICLES; ARRAYS; SCALE; STABILIZATION AB A generic approach for deploying various types of synthetic nanomaterials, including single-walled carbon nanotubes and nanoparticles, at well-defined locations on substrates is presented. The assembly is achieved through the complementary design of the stationary and carrier phases and utilizes the dewetting process during which polymer-encapsulated nanomaterials are delivered and positioned on predefined locations of substrates. Covalent modification of the nano-objects is not required for the building block positioning, therefore, preserving their intrinsic chemical and physical properties. The potency of this new approach is demonstrated for various synthetic nanomaterials, such as polystyrene, silica, and gold nanoparticles; as well as single-walled carbon nanotubes, showing highly specific and direct patterning of cm(2) areas using a generic assembly strategy. C1 Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Javey, A (reprint author), Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA. EM ajavey@eecs.berkeley.edu RI Ho, Johnny/K-5275-2012; Javey, Ali/B-4818-2013 OI Ho, Johnny/0000-0003-3000-8794; NR 36 TC 18 Z9 18 U1 2 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD SEP PY 2007 VL 7 IS 9 BP 2764 EP 2768 DI 10.1021/nl071271b PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 211CM UT WOS:000249501900040 PM 17661524 ER PT J AU Khanal, DR Wu, J AF Khanal, D. R. Wu, J. TI Gate coupling and charge distribution in nanowire field effect transistors SO NANO LETTERS LA English DT Article ID SEMICONDUCTOR NANOWIRES; HETEROSTRUCTURES; CAPACITANCE; OPTOELECTRONICS; ELECTROSTATICS; ELECTRONICS; DEVICES AB We have modeled the field and space charge distributions in back-gate and top-gate nanowire field effect transistors by solving the three-dimensional Poisson's equation numerically. It is found that the geometry of the gate oxide, the serniconductivity of the nanowire, and the finite length of the device profoundly affect both the total amount and the spatial distribution of induced charges in the nanowire, in stark contrast to the commonly accepted picture where metallic dielectric properties and infinite length are assumed for the nanowire and the specific geometry of the gate oxide is neglected. We provide a comprehensive set of numerical correction factors to the analytical capacitance formulas, as well as to numerical calculations that neglect the serniconductivity and finite length of the nanowire, that are frequently used for quantifying carrier transport in nanowire field effect transistors. C1 Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Wu, J (reprint author), Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. EM wuj@berkeley.edu RI Wu, Junqiao/G-7840-2011 OI Wu, Junqiao/0000-0002-1498-0148 NR 23 TC 89 Z9 89 U1 3 U2 23 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD SEP PY 2007 VL 7 IS 9 BP 2778 EP 2783 DI 10.1021/nl0713301 PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 211CM UT WOS:000249501900043 PM 17718588 ER PT J AU Trepagnier, EH Radenovic, A Sivak, D Geissler, P Liphardt, J AF Trepagnier, Eliane H. Radenovic, Aleksandra Sivak, David Geissler, Phillip Liphardt, Jan TI Controlling DNA capture and propagation through artificial nanopores SO NANO LETTERS LA English DT Article ID SOLID-STATE NANOPORE; TRANSLOCATION; MOLECULES AB Electrophorescing blopolymers across nanopores modulates the ionic current through the pore, revealing the polymer's diameter, length, and conformation. The rapidity of polymer translocation (similar to 30 000 bp/ms) in this geometry greatly limits the information that can be obtained for each base. Here we show that the translocation speed of lambda-DNA through artificial nanopores can be reduced using. optical tweezers. DNAs coupled to optically trapped beads were presented to nanopores. DNAs initially placed up to several micrometers from the pore could be captured. Subsequently, the optical tweezers reduced translocation speeds to 150 bp/ms, about 200-fold slower than free DNA. Moreover, the optical tweezers allowed us to "floss" single polymers back and forth through the pore. The combination of controlled sample presentation, greatly slowed translocation speeds, and repeated electrophoresis of single DNAs removes several barriers to using artificial nanopores for sequencing, haplotyping, and characterization of protein-DNA interactions. C1 Univ Calif Berkeley, Biophys Grad Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Coll Chem, Berkeley, CA 94720 USA. RP Liphardt, J (reprint author), Univ Calif Berkeley, Biophys Grad Grp, Berkeley, CA 94720 USA. EM Liphardt@physics.berkeley.edu RI Radenovic, Aleksandra/C-5350-2011; Liphardt, Jan/A-5906-2012; Sivak, David/A-1605-2012; OI Sivak, David/0000-0003-4815-4722; Liphardt, Jan/0000-0003-2835-5025 NR 23 TC 75 Z9 76 U1 0 U2 24 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD SEP PY 2007 VL 7 IS 9 BP 2824 EP 2830 DI 10.1021/nl0714334 PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 211CM UT WOS:000249501900051 PM 17705552 ER PT J AU Thurn, KT Brown, EMB Wu, A Vogt, S Lai, B Maser, J Paunesku, T Woloschak, GE AF Thurn, K. Ted Brown, Eric M. B. Wu, Aiguo Vogt, Stefan Lai, Barry Maser, Joerg Paunesku, Tatjana Woloschak, Gayle E. TI Nanoparticles for applications in cellular Imaging SO NANOSCALE RESEARCH LETTERS LA English DT Review DE nanoparticle; cellular uptake; quantum dots; titanium dioxide ID TITANIUM-DIOXIDE; QUANTUM DOTS; CELLS; ENDOCYTOSIS; CLATHRIN; INTERNALIZATION; PARTICLES; DELIVERY AB In the following review we discuss several types of nanoparticles (such as TiO2, quantum dots, and gold nanoparticles) and their impact on the ability to image biological components in fixed cells. The review also discusses factors influencing nanoparticle imaging and uptake in live cells in vitro. Due to their unique size-dependent properties nanoparticles offer numerous advantages over traditional dyes and proteins. For example, the photostability, narrow emission peak, and ability to rationally modify both the size and surface chemistry of Quantum Dots allow for simultaneous analyses of multiple targets within the same cell. On the other hand, the surface characteristics of nanometer sized TiO2 allow efficient conjugation to nucleic acids which enables their retention in specific subcellular compartments. We discuss cellular uptake mechanisms for the internalization of nanoparticles and studies showing the influence of nanoparticle size and charge and the cell type targeted on nanoparticle uptake. The predominant nanoparticle uptake mechanisms include clathrin-dependent mechanisms, macropinocytosis, and phagocytosis. C1 [Thurn, K. Ted; Brown, Eric M. B.; Wu, Aiguo; Paunesku, Tatjana; Woloschak, Gayle E.] Northwestern Univ, Dept Radiat Oncol, Robert E Lurie Canc Ctr, Feinberg Sch Med, Chicago, IL 60611 USA. [Vogt, Stefan; Lai, Barry] Argonne Natl Lab, Adv Photon Source, Xray Sci Div, Argonne, IL 60439 USA. [Maser, Joerg] Argonne Natl Lab, Adv Photon Source, Ctr Nanoscale Mat, Argonne, IL 60439 USA. [Paunesku, Tatjana; Woloschak, Gayle E.] Northwestern Univ, Dept Radiol, Robert E Lurie Canc Ctr, Feinberg Sch Med, Chicago, IL 60611 USA. [Woloschak, Gayle E.] Northwestern Univ, Dept Cell & Mol Biol, Robert E Lurie Canc Ctr, Feinberg Sch Med, Chicago, IL 60611 USA. RP Woloschak, GE (reprint author), Northwestern Univ, Dept Radiat Oncol, Robert E Lurie Canc Ctr, Feinberg Sch Med, 303 E Chicago Ave,Ward Bldg Room 13-007, Chicago, IL 60611 USA. EM g-woloschak@northwestern.edu RI Wu, Aiguo/C-1837-2015; Vogt, Stefan/B-9547-2009; Wu, Aiguo/A-5414-2008; Vogt, Stefan/J-7937-2013; Maser, Jorg/K-6817-2013; Paunesku, Tatjana/A-3488-2017; Woloschak, Gayle/A-3799-2017 OI Wu, Aiguo/0000-0001-7200-8923; Vogt, Stefan/0000-0002-8034-5513; Vogt, Stefan/0000-0002-8034-5513; Paunesku, Tatjana/0000-0001-8698-2938; Woloschak, Gayle/0000-0001-9209-8954 NR 115 TC 82 Z9 85 U1 4 U2 49 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1931-7573 J9 NANOSCALE RES LETT JI Nanoscale Res. Lett. PD SEP PY 2007 VL 2 IS 9 BP 430 EP 441 DI 10.1007/s11671-007-9081-5 PG 12 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Science & Technology - Other Topics; Materials Science; Physics GA 269NK UT WOS:000253655600002 PM 21794189 ER PT J AU Foltyn, SR Civale, L Macmanus-Driscoll, JL Jia, QX Maiorov, B Wang, H Maley, M AF Foltyn, S. R. Civale, L. Macmanus-Driscoll, J. L. Jia, Q. X. Maiorov, B. Wang, H. Maley, M. TI Materials science challenges for high-temperature superconducting wire SO NATURE MATERIALS LA English DT Review ID CRITICAL-CURRENT-DENSITY; YBCO-COATED CONDUCTORS; YBA2CU3O7-X THIN-FILMS; ARTIFICIAL PINNING CENTERS; PULSED-LASER DEPOSITION; SELF-ASSEMBLED NANODOTS; HIGH CRITICAL CURRENTS; COLUMNAR DEFECTS; RARE-EARTH; T-C AB Twenty years ago in a series of amazing discoveries it was found that a large family of ceramic cuprate materials exhibited superconductivity at temperatures above, and in some cases well above, that of liquid nitrogen. Imaginations were energized by the thought of applications for zero-resistance conductors cooled with an inexpensive and readily available cryogen. Early optimism, however, was soon tempered by the hard realities of these new materials: brittle ceramics are not easily formed into long flexible conductors; high current levels require near-perfect crystallinity; and-the downside of high transition temperature-performance drops rapidly in a magnetic field. Despite these formidable obstacles, thousands of kilometres of high-temperature superconducting wire have now been manufactured for demonstrations of transmission cables, motors and other electrical power components. The question is whether the advantages of superconducting wire, such as efficiency and compactness, can outweigh the disadvantage: cost. The remaining task for materials scientists is to return to the fundamentals and squeeze as much performance as possible from these wonderful and difficult materials. C1 Los Alamos Natl Lab, Superconductiv Technol Ctr, Los Alamos, NM 87545 USA. Univ Cambridge, Dept Mat Sci & Met, Cambridge CB2 3QZ, England. Texas A&M Univ, Dept Elect & Comp Engn, College Stn, TX 77843 USA. RP Foltyn, SR (reprint author), Los Alamos Natl Lab, Superconductiv Technol Ctr, POB 1663, Los Alamos, NM 87545 USA. EM sfoltyn@lanl.gov RI Jia, Q. X./C-5194-2008; Wang, Haiyan/P-3550-2014; OI Wang, Haiyan/0000-0002-7397-1209; Maiorov, Boris/0000-0003-1885-0436; Civale, Leonardo/0000-0003-0806-3113 NR 104 TC 378 Z9 384 U1 32 U2 231 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1476-1122 J9 NAT MATER JI Nat. Mater. PD SEP PY 2007 VL 6 IS 9 BP 631 EP 642 DI 10.1038/nmat1989 PG 12 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 207FE UT WOS:000249236200014 PM 17767181 ER PT J AU Polli, D Rini, M Wall, S Schoenlein, RW Tomioka, Y Tokura, Y Cerullo, G Cavalleri, A AF Polli, D. Rini, M. Wall, S. Schoenlein, R. W. Tomioka, Y. Tokura, Y. Cerullo, G. Cavalleri, A. TI Coherent orbital waves in the photo-induced insulator-metal dynamics of a magnetoresistive manganite SO NATURE MATERIALS LA English DT Article ID RAMAN-SCATTERING; LIGHT-PULSES; TRANSITION; PR0.7CA0.3MNO3; SPECTROSCOPY; DIFFRACTION; DRIVEN; LAMNO3; STATES; PHASE AB Photo-excitation can drive strongly correlated electron insulators into competing conducting phases(1,2,) resulting in giant and ultrafast changes of their electronic and magnetic properties. The underlying non-equilibrium dynamics involve many degrees of freedom at once, whereby sufficiently short optical pulses can trigger the corresponding collective modes of the solid along temporally coherent pathways. The characteristic frequencies of these modes range between the few GHz of acoustic vibrations(3) to the tens or even hundreds of THz for purely electronic excitations. Virtually all experiments so far have used 100 fs or longer pulses, detecting only comparatively slow lattice dynamics(4,5). Here, we use sub-10-fs optical pulses to study the photo-induced insulator-metal transition in the magnetoresistive manganite Pr0.7Ca0.3MnO3. At room temperature, we find that the time-dependent pathway towards the metallic phase is accompanied by coherent 31 THz oscillations of the optical reflectivity, significantly faster than all lattice vibrations. These high-frequency oscillations are suggestive of coherent orbital waves(6,7), crystal-field excitations triggered here by impulsive stimulated Raman scattering. Orbital waves are likely to be initially localized to the small polarons of this room-temperature manganite, coupling to other degrees of freedom at longer times, as photo-domains coalesce into a metallic phase. C1 Politecn Milan, Dipartimento Fis, ULTRAS INFM CNR, I-20133 Milan, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Correlated Electron Res Ctr, Tsukuba, Ibaraki 3058562, Japan. Rutherford Lab & Diamond Light Source, Cent Laser Facil, Chilton OX11 0DE, England. RP Cavalleri, A (reprint author), Politecn Milan, Dipartimento Fis, ULTRAS INFM CNR, I-20133 Milan, Italy. EM a.cavalleri1@physics.ox.ac.uk RI Polli, Dario/B-4809-2011; Tokura, Yoshinori/C-7352-2009; Cerullo, Giulio/F-6534-2011; Schoenlein, Robert/D-1301-2014; Wall, Simon/E-3771-2012; OI Polli, Dario/0000-0002-6960-5708; Schoenlein, Robert/0000-0002-6066-7566; Wall, Simon/0000-0002-6136-0224; Cerullo, Giulio/0000-0002-9534-2702 NR 35 TC 87 Z9 88 U1 6 U2 56 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1476-1122 J9 NAT MATER JI Nat. Mater. PD SEP PY 2007 VL 6 IS 9 BP 643 EP 647 DI 10.1038/nmat1979 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 207FE UT WOS:000249236200015 PM 17694062 ER PT J AU Mueggenburg, KE Lin, XM Goldsmith, RH Jaeger, HM AF Mueggenburg, Klara E. Lin, Xiao-Min Goldsmith, Rodney H. Jaeger, Heinrich M. TI Elastic membranes of close-packed nanoparticle arrays SO NATURE MATERIALS LA English DT Article ID THIN-FILMS; ASSEMBLIES; GOLD; NANOCRYSTALLITES; SUPERLATTICES; NANOMEMBRANES; PARTICLES AB Nanoparticle superlattices are hybrid materials composed of close-packed inorganic particles separated by short organic spacers. Most work so far has concentrated on the unique electronic, optical and magnetic behaviour of these systems(1-5). Here, we demonstrate that they also possess remarkable mechanical properties. We focus on two-dimensional arrays of close-packed nanoparticles(6,7) and show that they can be stretched across micrometre-size holes. The resulting freestanding monolayer membranes extend over hundreds of particle diameters without crosslinking of the ligands or further embedding in polymer. To characterize the membranes we measured elastic properties with force microscopy and determined the array structure using transmission electron microscopy. For dodecanethiol-ligated 6-nm-diameter gold nanocrystal monolayers, we find a Young's modulus of the order of several GPa. This remarkable strength is coupled with high flexibility, enabling the membranes to bend easily while draping over edges. The arrays remain intact and able to withstand tensile stresses up to temperatures around 370 K. The purely elastic response of these ultrathin membranes, coupled with exceptional robustness and resilience at high temperatures should make them excellent candidates for a wide range of sensor applications. C1 Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. Univ Chicago, Dept Phys, Chicago, IL 60637 USA. Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA. RP Jaeger, HM (reprint author), Univ Chicago, James Franck Inst, 929 E 57th St, Chicago, IL 60637 USA. EM h-jaeger@uchicago.edu NR 29 TC 253 Z9 253 U1 16 U2 148 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1476-1122 J9 NAT MATER JI Nat. Mater. PD SEP PY 2007 VL 6 IS 9 BP 656 EP 660 DI 10.1038/nmat1965 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 207FE UT WOS:000249236200018 PM 17643104 ER PT J AU Habas, SE Lee, H Radmilovic, V Somorjai, GA Yang, P AF Habas, Susan E. Lee, Hyunjoo Radmilovic, Velimir Somorjai, Gabor A. Yang, Peidong TI Shaping binary metal nanocrystals through epitaxial seeded growth SO NATURE MATERIALS LA English DT Article ID SILVER NANOWIRES; GOLD NANORODS; FORMIC-ACID; NANOPARTICLES; SIZE; NANOSTRUCTURES; HETERODIMERS; OXIDATION; HETEROSTRUCTURES; ELECTRODES AB Morphological control of nanocrystals has become increasingly important, as many of their physical and chemical properties are highly shape dependent. Nanocrystal shape control for both single- and multiple-material systems, however, remains empirical and challenging. New methods need to be explored for the rational synthetic design of heterostructures with controlled morphology. Overgrowth of a different material on well-faceted seeds, for example, allows for the use of the defined seed morphology to control nucleation and growth of the secondary structure. Here, we have used highly faceted cubic Pt seeds to direct the epitaxial overgrowth of a secondary metal. We demonstrate this concept with lattice-matched Pd to produce conformal shape-controlled core-shell particles, and then extend it to lattice-mismatched Au to give anisotropic growth. Seeding with faceted nanocrystals may have significant potential towards the development of shape-controlled heterostructures with defined interfaces. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Yang, P (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM p_yang@berkeley.edu RI Lee, Hyunjoo/G-8034-2012 OI Lee, Hyunjoo/0000-0002-4538-9086 NR 42 TC 750 Z9 755 U1 46 U2 466 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1476-1122 J9 NAT MATER JI Nat. Mater. PD SEP PY 2007 VL 6 IS 9 BP 692 EP 697 DI 10.1038/nmat1957 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 207FE UT WOS:000249236200025 PM 17618289 ER PT J AU Satishkumar, BC Brown, LO Gao, Y Wang, CC Wang, HL Doorn, SK AF Satishkumar, B. C. Brown, Leif O. Gao, Yuan Wang, Chun-Chih Wang, Hsing-Lin Doorn, Stephen K. TI Reversible fluorescence quenching in carbon nanotubes for biomolecular sensing SO NATURE NANOTECHNOLOGY LA English DT Article ID BIOSENSORS; BINDING; PROTEINS AB Biosensing applications of single-walled carbon nanotubes have been demonstrated in solid-state device structures(1-3). Bioanalyte sensing schemes based on coupling of reversible nanotube fluorescence quenching to redox reactions paired to enzymatic peroxide generation have also been pursued(4,5). Here we show a new approach to highly sensitive nanotube-based optical sensing. Single-walled carbon nanotubes interacting with dye ligand conjugates-a redox-active dye molecule that is covalently bound to a biological receptor ligand ( such as biotin in this case)-showed fluorescence quenching. Further interaction between the receptor ligand on the conjugates and target analytes ( avidin in this case) induced the recovery of the quenched fluorescence, forming the basis of the sensing scheme. Nanomolar sensitivity was attained with high specificity for the target analyte. This is a versatile approach because a wide range of conjugation possibilities exists between the potential receptors and redox quenchers. C1 Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP Satishkumar, BC (reprint author), Los Alamos Natl Lab, Div Chem, POB 1663, Los Alamos, NM 87545 USA. EM skdoorn@lanl.gov NR 18 TC 92 Z9 92 U1 4 U2 36 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1748-3387 J9 NAT NANOTECHNOL JI Nat. Nanotechnol. PD SEP PY 2007 VL 2 IS 9 BP 560 EP 564 DI 10.1038/nnano.2007.261 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Science & Technology - Other Topics; Materials Science GA 214HE UT WOS:000249727200015 PM 18654368 ER PT J AU Chen, Y Reeves, GD Friedel, RHW AF Chen, Yue Reeves, Geoffrey D. Friedel, Reiner H. W. TI The energization of relativistic electrons in the outer Van Allen radiation belt SO NATURE PHYSICS LA English DT Article ID PHASE-SPACE DENSITY; MAGNETIC-FIELD; GEOSYNCHRONOUS ORBIT; INNER MAGNETOSPHERE; ACCELERATION; PARTICLE; STORMS AB The origin and dynamics of the Van Allen radiation belts is one of the longest-standing questions of the space age, and one that is increasingly important for space applications as satellite systems become more sophisticated, smaller and more susceptible to radiation effects. The precise mechanism by which the Earth's magnetosphere is able to accelerate electrons from thermal to ultrarelativistic energies (E >> 0.5MeV) has been particularly difficult to definitively resolve. The traditional explanation is that large-scale, fluctuating electric and magnetic fields energize particles through radial diffusion. More recent theories(2,3) and observations(4,5) have suggested that gyro-resonant wave particle interactions may be comparable to or more important than radial diffusion. Using data collected simultaneously by multiple satellites passing through the magnetosphere at different distances from the Earth, we demonstrate that the latter of these is the dominant mechanism responsible for relativistic electron acceleration. Specifically, we identify frequent and persistent peaks in equatorial electron phase space density near or inside geosynchronous orbit that provide unambiguous evidence for local wave-particle acceleration. These observations represent an important step towards a more complete physical understanding of radiation belt dynamics and to the development of space-weather models. C1 Los Alamos Natl Lab, ISR Grp 1, Los Alamos, NM 87545 USA. RP Chen, Y (reprint author), Los Alamos Natl Lab, ISR Grp 1, POB 1663, Los Alamos, NM 87545 USA. EM cheny@lanl.gov RI Friedel, Reiner/D-1410-2012; Reeves, Geoffrey/E-8101-2011 OI Friedel, Reiner/0000-0002-5228-0281; Reeves, Geoffrey/0000-0002-7985-8098 NR 25 TC 141 Z9 145 U1 1 U2 7 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1745-2473 J9 NAT PHYS JI Nat. Phys. PD SEP PY 2007 VL 3 IS 9 BP 614 EP 617 DI 10.1038/nphys655 PG 4 WC Physics, Multidisciplinary SC Physics GA 217FL UT WOS:000249933700015 ER PT J AU Campisi, J di Fagagna, FD AF Campisi, Judith di Fagagna, Fabrizio d'Adda TI Cellular senescence: when bad things happen to good cells SO NATURE REVIEWS MOLECULAR CELL BIOLOGY LA English DT Review ID MAMMARY EPITHELIAL-CELLS; ONCOGENE-INDUCED SENESCENCE; NORMAL HUMAN FIBROBLASTS; DNA-DAMAGE RESPONSE; HISTONE DEACETYLASE INHIBITORS; LI-FRAUMENI-SYNDROME; RAS-INDUCED SENESCENCE; REPLICATIVE SENESCENCE; IN-VIVO; TUMOR SUPPRESSION AB Cells continually experience stress and damage from exogenous and endogenous sources, and their responses range from complete recovery to cell death. Proliferating cells can initiate an additional response by adopting a state of permanent cell-cycle arrest that is termed cellular senescence. Understanding the causes and consequences of cellular senescence has provided novel insights into how cells react to stress, especially genotoxic stress, and how this cellular response can affect complex organismal processes such as the development of cancer and ageing. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Buck Inst Age Res, Novato, CA 94945 USA. IFOM Fdn, FIRC Inst Mol Oncol, I-20139 Milan, Italy. RP Campisi, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM jcampisi@lbl.gov; fabrizio.dadda@ifom-ieo-campus.it OI DADDADIFAGAGNA, FABRIZIO/0000-0002-1976-3185 NR 157 TC 1445 Z9 1481 U1 47 U2 253 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1471-0072 J9 NAT REV MOL CELL BIO JI Nat. Rev. Mol. Cell Biol. PD SEP PY 2007 VL 8 IS 9 BP 729 EP 740 DI 10.1038/nrm2233 PG 12 WC Cell Biology SC Cell Biology GA 203ZP UT WOS:000249012900013 PM 17667954 ER PT J AU Reich, CW AF Reich, C. W. TI Nuclear data sheets for A=162 SO NUCLEAR DATA SHEETS LA English DT Review ID RARE-EARTH NUCLEI; HIGH-SPIN STATES; NEUTRON-DEFICIENT ISOTOPES; EVEN-EVEN NUCLEI; REDUCED TRANSITION-PROBABILITIES; ODD DEFORMED-NUCLEI; COLLECTIVE VIBRATIONAL STATES; MULTIPLE COULOMB-EXCITATION; ATOMIC-BEAM SPECTROSCOPY; INTERACTING BOSON MODEL AB The experimental results from the various reaction and radioactive decay studies leading to nuclides in the A=162 mass chain have been reviewed. These data are summarized and presented, together with adopted level schemes and properties, for the nuclides from Sm (Z=62) through Os (Z=76). This represents an update of the previous evaluation of the nuclear data on the A=162 nuclides (199911e2l) C1 Brookhaven Natl Lab, Natl Nucl Data Ctr, Upton, NY 11973 USA. RP Reich, CW (reprint author), Brookhaven Natl Lab, Natl Nucl Data Ctr, Upton, NY 11973 USA. NR 378 TC 17 Z9 17 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0090-3752 EI 1095-9904 J9 NUCL DATA SHEETS JI Nucl. Data Sheets PD SEP PY 2007 VL 108 IS 9 BP 1807 EP + DI 10.1016/j.nds.2007.07.002 PG 227 WC Physics, Nuclear SC Physics GA 216CJ UT WOS:000249855100001 ER PT J AU Zuber, N Rohatgi, US Wulff, W Catton, I AF Zuber, Novak Rohatgi, Upendra S. Wulff, Wolfgang Catton, Ivan TI Application of fractional scaling analysis (FSA) to loss of coolant accidents (LOCA) - Methodology development SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 11th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-11) CY OCT 02-06, 2005 CL Avignon, FRANCE AB A quantitative methodology is developed to (a) scale time-dependent evolution processes involving an aggregate of interacting modules and processes (such as a NPP) and (b) integrate and organize information and data of interest to NPP design and safety analyses. The methodology is based on two concepts: fractional scaling and hierarchy. Fractional scaling is used to provide a synthesis of experimental data to generate quantitative criteria for assessing the effects of various design and operating parameters on thermo-hydraulic processes in a NPP. The synthesis via fractional scaling is carried out at three hierarchical levels: process, component and system. The methodology is demonstrated by applying it to a LOCA. The fractional scaling analysis (FSA) identifies dominant processes, ranks them quantitatively according to their importance and provides thereby an objective basis for establishing phenomena identification and ranking tables (PIRT) as well as a basis for conducting uncertainty analyses. The paper also discusses the benefits to be realized by applying the methodology to presently operating NPP as well as to future design of NPP. 2007 Published by Elsevier B.V. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. RP Zuber, N (reprint author), 703 New Mark Esplanade, Rockville, MD 20850 USA. NR 16 TC 5 Z9 5 U1 1 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD SEP PY 2007 VL 237 IS 15-17 BP 1593 EP 1607 DI 10.1016/j.nucengdes.2007.01.017 PG 15 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 206AT UT WOS:000249157000004 ER PT J AU Kang, KH Park, RJ Kim, SB Suh, KY Cheung, FB Rempe, JL AF Kang, Kyoung-Ho Park, Rae-Joon Kim, Sang-Baik Suh, K. Y. Cheung, F. B. Rempe, J. L. TI Simulant melt experiments on performance of the in-vessel core catcher SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 11th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-11) CY OCT 02-06, 2005 CL Avignon, FRANCE ID CRITICAL HEAT-FLUX; RETENTION; SURFACE AB In order to enhance the feasibility of in-vessel retention (IVR) of molten core material during a severe accident for high-power reactors, an in-vessel core catcher (IVCC) was designed and evaluated as part of a joint United States-Korean International Nuclear Energy Research Initiative (INERI). The proposed IVCC is expected to increase the thermal margin for success of IVR by providing an "engineered gap" for heat transfer from materials that relocate during a severe accident and potentially serving as a sacrificial material under a severe accident. In this study, LAVA-GAP experiments were performed to investigate the thermal and mechanical performance of the IVCC using the alumina melt as simulant. The LAVA-GAP experiments aim to examine the feasibility and sustainability of the IVCC under the various test conditions using 1/8th scale hemispherical test sections. As a feasibility test of the proposed IVCC in this INERI project, the effects of IVCC base steel materials, internal coating materials, and gap size between the IVCC and the vessel lower head were examined. The test results indicated that the internally coated IVCC has high thermal performance compared with the uncoated IVCC. In terms of integrity of the base steel, carbon steel is superior to stainless steel and the effect of bond coat is found to be trivial for the tests performed in this study. The thermal load is mitigated via boiling heat removal in the gap between the IVCC and the vessel lower head. The current test results imply that gaps less than 10 mm are not enough to guarantee effective cooling induced by water ingression and steam venting there through. Selection of endurable material and pertinent gap size is needed to implement the proposed IVCC concept into advanced reactor designs. (c) 2007 Elsevier B.V. All rights reserved. C1 Korea Atom Energy Res Inst, Severe Accident Res Project, Thermal Hydraul Safety Res Div, Taejon 305353, South Korea. Seoul Natl Univ, Seoul, South Korea. Penn State Univ, University Pk, PA 16802 USA. Idaho Natl Lab, Idaho Falls, ID USA. RP Kang, KH (reprint author), Korea Atom Energy Res Inst, Severe Accident Res Project, Thermal Hydraul Safety Res Div, 150 Dukjin Dong, Taejon 305353, South Korea. EM khkang@kaeri.re.kr OI Rempe, Joy/0000-0001-5527-3549 NR 18 TC 6 Z9 6 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD SEP PY 2007 VL 237 IS 15-17 BP 1803 EP 1813 DI 10.1016/j.nucengdes.2007.03.017 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 206AT UT WOS:000249157000022 ER PT J AU Granetz, RS Hollmann, EM Whyte, DG Izzo, VA Antar, GY Bader, A Bakhtiari, M Biewer, T Boedo, JA Evans, TE Hutchinson, IH Jernigan, TC Gray, DS Groth, M Humphreys, DA Lasnier, CJ Moyer, RA Parks, PB Reinke, ML Rudakov, DL Strait, EJ Terry, JL Wesley, J West, WP Wurden, G Yu, J AF Granetz, R. S. Hollmann, E. M. Whyte, D. G. Izzo, V. A. Antar, G. Y. Bader, A. Bakhtiari, M. Biewer, T. Boedo, J. A. Evans, T. E. Hutchinson, I. H. Jernigan, T. C. Gray, D. S. Groth, M. Humphreys, D. A. Lasnier, C. J. Moyer, R. A. Parks, P. B. Reinke, M. L. Rudakov, D. L. Strait, E. J. Terry, J. L. Wesley, J. West, W. P. Wurden, G. Yu, J. TI Gas jet disruption mitigation studies on Alcator C-Mod and DIII-D SO NUCLEAR FUSION LA English DT Article ID INJECTION; IMPURITY AB High-pressure noble gas jet injection is a mitigation technique which potentially satisfies the requirements of fast response time and reliability, without degrading subsequent discharges. Previously reported gas jet experiments on DIII-D showed good success at reducing deleterious disruption effects. In this paper, results of recent gas jet disruption mitigation experiments on Alcator C-Mod and DIII-D are reported. Jointly, these experiments have greatly improved the understanding of gas jet dynamics and the processes involved in mitigating disruption effects. In both machines, the sequence of events following gas injection is observed to be quite similar: the jet neutrals stop near the plasma edge, the edge temperature collapses and large MHD modes are quickly destabilized, mixing the hot plasma core with the edge impurity ions and radiating away the plasma thermal energy. High radiated power fractions are achieved, thus reducing the conducted heat loads to the chamber walls and divertor. A significant (2x or more) reduction in halo current is also observed. Runaway electron generation is small or absent. These similar results in two quite different tokamaks are encouraging for the applicability of this disruption mitigation technique to ITER. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Univ Calif San Diego, FERP, La Jolla, CA 92093 USA. Univ Wisconsin, Dept Engn Phys, Madison, WI 53706 USA. Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Granetz, RS (reprint author), MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. EM granetz@mit.edu; ehollmann@ucsd.edu RI Hutchinson, Ian/D-1136-2009; Groth, Mathias/G-2227-2013; Wurden, Glen/A-1921-2017 OI Hutchinson, Ian/0000-0003-4276-6576; Wurden, Glen/0000-0003-2991-1484 NR 12 TC 49 Z9 49 U1 0 U2 5 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP 1086 EP 1091 DI 10.1088/0029-5515/47/9/003 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800006 ER PT J AU Garofalo, AM Jackson, GL La Haye, RJ Okabayashi, M Reimerdes, H Strait, EJ Ferron, JR Groebner, RJ In, Y Lanctot, MJ Matsunaga, G Navratil, GA Solomon, WM Takahashi, H Takechi, M Turnbull, AD AF Garofalo, A. M. Jackson, G. L. La Haye, R. J. Okabayashi, M. Reimerdes, H. Strait, E. J. Ferron, J. R. Groebner, R. J. In, Y. Lanctot, M. J. Matsunaga, G. Navratil, G. A. Solomon, W. M. Takahashi, H. Takechi, M. Turnbull, A. D. CA DIII-D Team TI Stability and control of resistive wall modes in high beta, low rotation DIII-D plasmas SO NUCLEAR FUSION LA English DT Article ID FEEDBACK STABILIZATION; ERROR-FIELD; TOKAMAKS; INSTABILITIES; DISCHARGES; LIMIT; COILS AB Recent high-beta DIII-D (Luxon J.L. 2002 Nucl. Fusion 42 64) experiments with the new capability of balanced neutral beam injection show that the resistive wall mode (RWM) remains stable when the plasma rotation is lowered to a fraction of a per cent of the Alfven frequency by reducing the injection of angular momentum in discharges with minimized magnetic field errors. Previous DIII-D experiments yielded a high plasma rotation threshold (of order a few per cent of the Alfven frequency) for RWM stabilization when resonant magnetic braking was applied to lower the plasma rotation. We propose that the previously observed rotation threshold can be explained as the entrance into a forbidden band of rotation that results from torque balance including the resonant field amplification by the stable RWM. Resonant braking can also occur naturally in a plasma subject to magnetic instabilities with a zero frequency component, such as edge localized modes. In DIII-D, robust RWM stabilization can be achieved using simultaneous feedback control of the two sets of non-axisymmetric coils. Slow feedback control of the external coils is used for dynamic error field correction; fast feedback control of the internal non-axisymmetric coils provides RWM stabilization during transient periods of low rotation. This method of active control of the n = I RWM has opened access to new regimes of high performance in DIII-D. Very high plasma pressure combined with elevated q(min) for high bootstrap current fraction, and internal transport barriers for high energy confinement, are sustained for almost 2 s, or 10 energy confinement times, suggesting a possible path to high fusion performance, steady-state tokamak scenarios. C1 Columbia Univ, New York, NY 10027 USA. Gen Atom Co, San Diego, CA 92186 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. FARTECH Inc, San Diego, CA 92121 USA. Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. RP Garofalo, AM (reprint author), Columbia Univ, New York, NY 10027 USA. EM garofalo@fusion.gat.com RI Lanctot, Matthew J/O-4979-2016; OI Lanctot, Matthew J/0000-0002-7396-3372; Solomon, Wayne/0000-0002-0902-9876 NR 38 TC 53 Z9 53 U1 0 U2 6 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP 1121 EP 1130 DI 10.1088/0029-5515/47/9/008 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800011 ER PT J AU Clark, DS Tabak, M AF Clark, D. S. Tabak, M. TI A self-similar isochoric implosion for fast ignition SO NUCLEAR FUSION LA English DT Article ID COLLAPSING CAVITIES; FUSION; TARGETS; COMPRESSION AB Various gain models have shown the potentially great advantages of fast ignition (FI) inertial confinement fusion (ICF) over its conventional hot spot ignition counterpart (e.g. Atzeni S. 1999 Phys. Plasmas 6 3316; Tabak M. et al 2006 Fusion Sci. Technol. 49 254). These gain models, however, all assume nearly uniform density fuel assemblies. In contrast, conventional ICF implosions yield hollowed fuel assemblies with a high-density shell of fuel surrounding a low-density, high-pressure hot spot. Hence, to realize fully the advantages of FI, an alternative implosion design must be found which yields nearly isochoric fuel assemblies without substantial hot spots. Here, it is shown that a self-similar spherical implosion of the type originally studied by Guderley (1942 Luffiahrtforschung 19 302) may be employed to yield precisely such quasi-isochoric imploded states. The difficulty remains, however, of accessing these self-similarly imploding configurations from initial conditions representing an actual ICF target, namely a uniform, solid-density shell at rest. Furthermore, these specialized implosions must be realized for practicable drive parameters and at the scales and energies of interest in ICE A direct-drive implosion scheme is presented which meets all of these requirements and reaches a nearly isochoric assembled density of 300 g cm(-3) and areal density of 2.4 g cm(-2) using 485 kJ of laser energy. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Clark, DS (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM clark90@llnl.gov NR 30 TC 21 Z9 21 U1 0 U2 5 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP 1147 EP 1156 DI 10.1088/0029-5515/47/9/011 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800014 ER PT J AU Lipschultz, B Bonnin, X Counsell, G Kallenbach, A Kukushkin, A Krieger, K Leonard, A Loarte, A Neu, R Pitts, RA Rognlien, T Roth, J Skinner, C Terry, JL Tsitrone, E Whyte, D Zweben, S Asakura, N Coster, D Doerner, R Dux, R Federici, G Fenstermacher, M Fundamenski, W Ghendrih, P Herrmann, A Hu, J Krasheninnikov, S Kirnev, G Kreter, A Kurnaev, V LaBombard, B Lisgo, S Nakano, T Ohno, N Pacher, HD Paley, J Pan, Y Pautasso, G Philipps, V Rohde, V Rudakov, D Stangeby, P Takamura, S Tanabe, T Yang, Y Zhu, S AF Lipschultz, B. Bonnin, X. Counsell, G. Kallenbach, A. Kukushkin, A. Krieger, K. Leonard, A. Loarte, A. Neu, R. Pitts, R. A. Rognlien, T. Roth, J. Skinner, C. Terry, J. L. Tsitrone, E. Whyte, D. Zweben, S. Asakura, N. Coster, D. Doerner, R. Dux, R. Federici, G. Fenstermacher, M. Fundamenski, W. Ghendrih, P. Herrmann, A. Hu, J. Krasheninnikov, S. Kirnev, G. Kreter, A. Kurnaev, V. LaBombard, B. Lisgo, S. Nakano, T. Ohno, N. Pacher, H. D. Paley, J. Pan, Y. Pautasso, G. Philipps, V. Rohde, V. Rudakov, D. Stangeby, P. Takamura, S. Tanabe, T. Yang, Y. Zhu, S. TI Plasma-surface interaction, scrape-off layer and divertor physics: implications for ITER SO NUCLEAR FUSION LA English DT Review ID ALCATOR C-MOD; DIII-D TOKAMAK; FUSION TEST REACTOR; ASDEX UPGRADE; EDGE PLASMA; I ELMS; DISRUPTION MITIGATION; CHEMICAL EROSION; HEAT LOADS; MAIN-WALL AB Recent research in scrape-off layer (SOL) and divertor physics is reviewed; new and existing data from a variety of experiments have been used to make cross-experiment comparisons with implications for further research and ITER. Studies of the region near the separatrix have addressed the relationship of profiles to turbulence as well as the scaling of the parallel power flow. Enhanced low-field side radial transport is implicated as driving parallel flows to the inboard side. The medium-n nature of edge localized modes (ELMs) has been elucidated and new measurements have determined that they carry similar to 10-20% of the ELM energy to the far SOL with implications for ITER limiters and the upper divertor. The predicted divertor power loads for ITER disruptions are reduced while those to main chamber plasma facing components (PFCs) increase. Disruption mitigation through massive gas puffing is successful at reducing PFC heat loads. New estimates of ITER tritium retention have shown tile sides to play a significant role; tritium cleanup may be necessary every few days to weeks. ITER's use of mixed materials gives rise to a reduction of surface melting temperatures and chemical sputtering. Advances in modelling of the ITER divertor and flows have enhanced the capability to match experimental data and predict ITER performance. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02319 USA. Univ Paris 13, CNRS, UPR 1311, LIMHP, F-93430 Villetaneuse, France. UKAEA Euratom Fus Assoc, Culham Sci Res Ctr, Abingdon 113, Oxon, England. ITER Int Team, Garching Working Site, D-85748 Garching, Germany. DIII D Natl Fus Facil, San Diego, CA 92186 USA. EFDA, Close Support Unit Garching, D-85748 Garching, Germany. Assoc Euratom Confederat Suisse, EPFL, CRPP, CH-1015 Lausanne, Switzerland. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. CEA Cadarache, DSM DRFC, EURATOM Assoc, F-12108 St Paul Les Durance, France. Japan Atom Energy Agcy, Ibaraki 3110193, Japan. Univ Calif San Diego, Energy Res Ctr, La Jolla, CA 92093 USA. Acad Sinica, Inst Plasma Phys, Hefei 230031, Peoples R China. RRC Kurchov Inst, Nucl Fus Inst, Moscow 123182, Russia. Forschungszentrum Julich, EURATOM Assoc, D-52425 Julich, Germany. Moscow Engn Phys Inst, Dubna 141980, Moscow Region, Russia. Univ Toronto, Inst Aerosp Studies, N York, ON M3H 5T6, Canada. Nagoya Univ, Grad Sch Engn, Dept Energy Engn & Sci, Nagoya, Aichi 4648603, Japan. INRS EMT, Varennes, PQ J3X 1S2, Canada. Southwestern Inst Plasma Phys, Chengdu, Peoples R China. Kyushu Univ, Dept Adv Energy Engn Sci, Fukuoka 8128581, Japan. RP Lipschultz, B (reprint author), MIT, Plasma Sci & Fus Ctr, 175 Albany St, Cambridge, MA 02319 USA. EM blip@psfe.mit.edu RI Lipschultz, Bruce/J-7726-2012; Coster, David/B-4311-2010; U-ID, Kyushu/C-5291-2016; Krieger, Karl/F-9762-2014; Kurnaev, Valery/S-3946-2016; Neu, Rudolf /B-4438-2010; OI Lipschultz, Bruce/0000-0001-5968-3684; Coster, David/0000-0002-2470-9706; Krieger, Karl/0000-0003-0427-8184; Neu, Rudolf /0000-0002-6062-1955; Bonnin, Xavier/0000-0002-6743-1062 NR 140 TC 89 Z9 90 U1 3 U2 52 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0029-5515 EI 1741-4326 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP 1189 EP 1205 DI 10.1088/0029-5515/47/9/016 PG 17 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800019 ER PT J AU Zhurovich, K Fiore, CL Ernst, DR Bonoli, PT Greenwald, MJ Hubbard, AE Hughes, JW Marmar, ES Mikkelsen, DR Phillips, P Rice, JE AF Zhurovich, K. Fiore, C. L. Ernst, D. R. Bonoli, P. T. Greenwald, M. J. Hubbard, A. E. Hughes, J. W. Marmar, E. S. Mikkelsen, D. R. Phillips, P. Rice, J. E. TI Microturbulent drift mode suppression as a trigger mechanism for internal transport barriers on Alcator C-Mod SO NUCLEAR FUSION LA English DT Article ID REVERSED MAGNETIC SHEAR; H-MODE; TOKAMAK; TURBULENCE; PLASMAS; CONFINEMENT; DISCHARGES; STABILITY; UPGRADE; PROFILE AB Internal transport barriers (ITBs) can be routinely produced in enhanced D-alpha (EDA) H-mode discharges on the Alcator C-Mod tokamak by putting the minority ion cyclotron resonance layer at |r/a| >= 0.5 during the current flat top phase of the discharge. These ITBs are characterized by density peaking at constant temperature and are therefore both particle and energy transport barriers. The ITB formation appears to result from widening the region near the magnetic axis in which toroidal drift modes are stable, allowing the Ware pinch to peak the density profile. Experimental evidence shows that shifting the ICRF resonance off-axis results in a local flattening of ion and electron temperature profiles. TRANSP calculations of ion temperature profiles support this experimentally observed trend. Stability analysis of ion temperature gradient (ITG) and electron temperature gradient modes at times before ITB formation is done using the linear gyrokinetic code GS2. These gyrokinetic calculations find that the most unstable modes in the C-Mod EDA H-mode core, prior to ITB onset, are the toroidal ITG driven type. These modes are suppressed in the ITB region through a temperature gradient reduction when the ICRF resonance is shifted off-axis. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Texas, Fus Res Ctr, Austin, TX 78712 USA. RP Zhurovich, K (reprint author), MIT, Plasma Sci & Fus Ctr, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Ernst, Darin/A-1487-2010; OI Ernst, Darin/0000-0002-9577-2809; Greenwald, Martin/0000-0002-4438-729X NR 42 TC 4 Z9 4 U1 0 U2 0 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP 1220 EP 1231 DI 10.1088/0029-5515/47/9/019 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800022 ER PT J AU Dinklage, A Maassberg, H Preuss, R Irkin, YA Yamada, H Ascasibar, E Beidler, CD Funaba, H Harris, JH Kus, A Murakami, S Okamura, S Sano, F Stroth, U Suzuki, Y Talmadge, J Tribaldos, V Watanabe, KY Werner, A Weller, A Yokoyama, M AF Dinklage, A. Maassberg, H. Preuss, R. Irkin, Yu. A. Yamada, H. Ascasibar, E. Beidler, C. D. Funaba, H. Harris, J. H. Kus, A. Murakami, S. Okamura, S. Sano, F. Stroth, U. Suzuki, Y. Talmadge, J. Tribaldos, V. Watanabe, K. Y. Werner, A. Weller, A. Yokoyama, M. TI Physical model assessment of the energy confinement time scaling in stellarators SO NUCLEAR FUSION LA English DT Article ID ELECTRON-ROOT FEATURE; WENDELSTEIN-7-AS STELLARATOR; W7-AS; TRANSPORT; DATABASE; PLASMAS; BETA; FIELD; LHD AB The International Stellarator Confinement Database (ISCDB) is a joint effort of the helical device community. It is publicly available at http://www.ipp.mpg.de/ISS and http://iscdb.nifs.ac.jp. The validity of physics models is investigated employing ISCDB data. Bayesian model comparison shows differences in the confinement scaling of data subgroups. Theory-based assessment of pure neoclassical transport regimes, however, indicates scalability which is supported by experimental results in specific W7-AS scenarios. Therefore, neoclassical simulations are employed for predictive purposes in W7-X, accounting for effects due to power deposition, plasma profiles and the ambipolar radial electric field. Neoclassical case studies for W7-X are presented as examples for the neoclassical predictions to be considered as an upper limit of plasma performance. C1 EURATOM, Max Planck Inst Plasma Phys, Greifswald, Germany. Natl Inst Fus Sci, Gifu 5095292, Japan. CIEMAT, EURATOM, Lab Nacl Fus, E-28040 Madrid, Spain. Australian Natl Univ, Canberra, ACT, Australia. Oak Ridge Natl Lab, Oak Ridge, TN USA. Kyoto Univ, Dept Nucl Engn, Kyoto 6068501, Japan. Kyoto Univ, Inst Adv Energy, Uji 6110011, Japan. Univ Stuttgart, Inst Plasmaforsch, D-7000 Stuttgart, Germany. Univ Wisconsin, Madison, WI USA. RP Dinklage, A (reprint author), EURATOM, Max Planck Inst Plasma Phys, Greifswald, Germany. EM dinklage@ipp.mpg.de RI Tribaldos, Victor/K-4299-2012; Murakami, Sadayoshi/A-2191-2016; Ascasibar, Enrique/B-7498-2014 OI Tribaldos, Victor/0000-0002-8683-9338; Murakami, Sadayoshi/0000-0002-2526-7137; Ascasibar, Enrique/0000-0001-8124-0994 NR 25 TC 16 Z9 16 U1 0 U2 5 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP 1265 EP 1273 DI 10.1088/0029-5515/47/9/025 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800028 ER PT J AU Kessel, CE Giruzzil, G Sips, ACC Budny, RV Artaud, JF Basiuk, V Imbeaux, F Joffrin, E Schneider, M Murakami, M Luce, T St John, H Oikawa, T Hayashi, N Takizuka, T Ozeki, T Na, YS Park, JM Garcia, J Tucillo, AA AF Kessel, C. E. Giruzzil, G. Sips, A. C. C. Budny, R. V. Artaud, J. F. Basiuk, V. Imbeaux, F. Joffrin, E. Schneider, M. Murakami, M. Luce, T. St John, Holger Oikawa, T. Hayashi, N. Takizuka, T. Ozeki, T. Na, Y.-S. Park, J. M. Garcia, J. Tucillo, A. A. TI Simulation of the hybrid and steady state advanced operating modes in ITER SO NUCLEAR FUSION LA English DT Article ID GENERAL AXISYMMETRICAL EQUILIBRIA; NEUTRAL BEAM INJECTION; PARTICLE SOURCE RATES; BOOTSTRAP CURRENT; CURRENT DRIVE; NEOCLASSICAL CONDUCTIVITY; ARBITRARY COLLISIONALITY; TRANSPORT BARRIERS; TOKAMAK PLASMA; CURRENT HOLE AB Integrated simulations are performed to establish a physics basis, in conjunction with present tokamak experiments, for the operating modes in the International Thermonuclear Experimental Reactor (ITER). Simulations of the hybrid mode are done using both fixed and free-boundary 1.5D transport evolution codes including CRONOS, ONETWO, TSC/TRANSP, TOPICS and ASTRA. The hybrid operating mode is simulated using the GLF23 and CDBM05 energy transport models. The injected powers are limited to the negative ion neutral beam, ion cyclotron and electron cyclotron heating systems. Several plasma parameters and source parameters are specified for the hybrid cases to provide a comparison of 1.5D core transport modelling assumptions, source physics modelling assumptions, as well as numerous peripheral physics modelling. Initial results indicate that very strict guidelines will need to be imposed on the application of GLF23, for example, to make useful comparisons. Some of the variations among the simulations are due to source models which vary widely among the codes used. In addition, there are a number of peripheral physics models that should be examined, some of which include fusion power production, bootstrap current, treatment of fast particles and treatment of impurities. The hybrid simulations project to fusion gains of 5.6-8.3, beta(N) values of 2.1-2.6 and fusion powers ranging from 350 to 500 MW, under the assumptions outlined in section 3. Simulations of the steady state operating mode are done with the same 1.5D transport evolution codes cited above, except the ASTRA code. In these cases the energy transport model is more difficult to prescribe, so that energy confinement models will range from theory based to empirically based. The injected powers include the same sources as used for the hybrid with the possible addition of lower hybrid. The simulations of the steady state mode project to fusion gains of 3.5-7, beta(N) Values of 2.31-3.0 and fusion powers of 290 to 415 MW, under the assumptions described in section 4. These simulations will be presented and compared with particular focus on the resulting temperature profiles, source profiles and peripheral physics profiles. The steady state simulations are at an early stage and are focused on developing a range of safety factor profiles with 100% non-inductive current. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. CEA Cadarache, EURATOM Assoc, St Paul Les Durance, France. Max Planck Inst Plasma Phys, EURATOM Assoc, D-85748 Garching, Germany. Oak Ridge Natl Lab, Oak Ridge, TN USA. Gen Atom Co, San Diego, CA USA. ITER Naka Joint Work Site, ITER Int Team, Naka, Ibaraki, Japan. Japan Atom Energy Agcy, Naka, Ibaraki, Japan. Natl Fus Res Ctr, Taejon 305333, South Korea. Univ Politecn Cataluna, Barcelona, Spain. CR ENEA Frascati, ENEA, EURATOM Assoc, Rome, Italy. RP Kessel, CE (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. EM ckessel@pppl.gov RI Schneider, Mireille/B-7821-2010; Artaud, Jean-Francois/G-8480-2011; Imbeaux, Frederic/A-7614-2013; Artaud, Jean-Francois/J-2068-2012 NR 58 TC 66 Z9 67 U1 4 U2 17 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP 1274 EP 1284 DI 10.1088/0029-5515/47/9/026 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800029 ER PT J AU Gao, QD Budny, RV Jiao, YM Indireshkumar, K AF Gao, Q. D. Budny, R. V. Jiao, Y. M. Indireshkumar, K. TI Current profile control and optimization under dominant electron heating in HL-2A SO NUCLEAR FUSION LA English DT Article ID INTERNAL TRANSPORT BARRIERS; H-MODE DISCHARGES; CURRENT DRIVE; ASDEX UPGRADE; DIII-D; JET; TOKAMAK; PLASMA; ITER; ION AB The establishment of the current profile as in the hybrid scenario is studied under the condition of dominant electron heating in HL-2A. The scenarios with injecting lower hybrid (LH) and electron cyclotron (EC) waves are under numerical study. Carefully adjusting the position of non-inductive current driven by two groups of gyrotron, an optimized q-profile was obtained with q(a) = 3.78 and a weak shear region extending to rho similar to 0.45 (where rho is the square-root of toroidal flux normalized to its value at the plasma boundary) in low-density discharges of (n) over bar (e) = 1.0 x 10(19) m(-3). When 0.5 MW LH power in the current drive mode and 0.95 MW EC power mainly for plasma heating are used to control the current profile, a hybrid discharge scenario with a weak magnetic shear region extended to rho = 0.6 and q(a) = 3.21 is established by controlling the EC absorption position. The mechanism of the LH wave absorption in the HL-2A plasma causes interplay of the distribution of the LH driven current with the modification of the plasma configuration, which constitutes non-linearity in the LH wave deposition. Due to the non-linearity the LH wave deposition position changes spontaneously or oscillates. The oscillatory behaviour caused by the non-linear effect of the LH wave deposition is analysed. C1 SW Inst Phys, Chengdu 610041, Peoples R China. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Gao, QD (reprint author), SW Inst Phys, POB 432, Chengdu 610041, Peoples R China. EM qgao@swip.ac.cn NR 29 TC 6 Z9 7 U1 0 U2 2 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP 1318 EP 1325 DI 10.1088/0029-5515/47/9/032 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800035 ER PT J AU Gates, DA Menard, J Maingi, R Kaye, S Sabbagh, SA Diem, S Wilson, JR Bell, MG Bell, RE Ferron, J Fredrickson, ED Kessel, CE LeBlanc, BP Levinton, F Manickam, J Mueller, D Ramad, R Stevenson, T Stutman, D Taylor, G Tritz, K Yu, H AF Gates, D. A. Menard, J. Maingi, R. Kaye, S. Sabbagh, S. A. Diem, S. Wilson, J. R. Bell, M. G. Bell, R. E. Ferron, J. Fredrickson, E. D. Kessel, C. E. LeBlanc, B. P. Levinton, F. Manickam, J. Mueller, D. Ramad, R. Stevenson, T. Stutman, D. Taylor, G. Tritz, K. Yu, H. CA NSTX Res Team TI Progress towards steady state at low aspect ratio on the National Spherical Torus Experiment (NSTX) SO NUCLEAR FUSION LA English DT Article ID TIME EQUILIBRIUM RECONSTRUCTION; CONTROL-SYSTEM; PLASMAS; TOKAMAK; REGIME; BETA; ST AB Modifications to the plasma control capabilities and poloidal field coils of the National Spherical Torus Experiment (NSTX) have enabled a significant enhancement in shaping capability which has led to the transient achievement of a record shape factor (S equivalent to q95 (I-p/a B-t)) of similar to 41 (MA m- I T- 1) simultaneous with a record plasma elongation of K bla similar to 3. This result was obtained using isoflux control and real-time equilibrium reconstruction. Achieving high shape factor together with tolerable divertor loading is an important result for future ST burning plasma experiments as exemplified by studies for future ST reactor concepts, as well as neutron producing devices, which rely on achieving high shape factors in order to achieve steady state operation while maintaining MHD stability. Statistical evidence is presented which demonstrates the expected correlation between increased shaping and improved plasma performance. Plasmas with high shape factor have been sustained for pulse lengths which correspond to tau(pulse),, = 1.6s similar to 50 tau(E) similar to 5 tau(CR), where tau(CR) is the current relaxation time and tau(E) is the energy confinement time. Plasmas with higher similar to 20% have been sustained for tau(pulse), = 1.2s similar to 25TE similar to 3TCR with non-inductive current fractions f(NI) similar to 50%, with similar to 40% pressure driven current and similar to 10% neutral beam driven current. An interesting feature of these discharges is the observation that the central value of the safety factor q (0) remains elevated and constant for several current diffusion times without sawteeth, similar to the 'hybrid mode'. Calculations of the profiles of inductive and non-inductive current are compared with measurements of the total current profile and are shown to be in quantitative agreement. Results are shown from experiments which investigate the applicability of high harmonic fast waves (HHFWs) and electron Bernstein waves (EBWs) as current drive and heating sources, and the possibility of LHCD for future ST devices is raised. A calculated scenario which provides 100% non-inductive current drive is described. NSTX operates with peak divertor heat fluxes which are in the same range as those expected for the ITER device, i.e. with P-heatmax similar to 10MW m(-2). High triangularity, high elongation plasmas on NSTX have been demonstrated to have reduced peak heat flux to the divertor plates to < 3 MW m(-2). C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Columbia Univ, Dept Appl Phys, New York, NY 10027 USA. Gen Atom Co, San Diego, CA USA. Nova Photon, Princeton, NJ USA. Univ Washington, Seattle, WA 98195 USA. Johns Hopkins Univ, Baltimore, MD USA. RP Gates, DA (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Sabbagh, Steven/C-7142-2011; Stutman, Dan/P-4048-2015; OI Menard, Jonathan/0000-0003-1292-3286 NR 32 TC 8 Z9 8 U1 0 U2 5 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP 1376 EP 1382 DI 10.1088/0029-5515/47/9/040 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800043 ER PT J AU Den Hartog, DJ Ahn, JW Almagri, AF Anderson, JK Beklemishev, AD Blair, AP Bonomo, F Borchardt, MT Brower, DL Burke, DR Cengher, M Chapman, BE Choi, S Clayton, DJ Cox, WA Combs, SK Craigi, D Cummings, HD Davydenko, VI Demers, DR Deng, BH Ding, WX Ebrahimi, F Ennis, DA Fiksel, G Foust, C Forest, CB Franz, P Frassinetti, L Gangadhara, S Goetz, JA Harvey, RW Holly, DJ Hudson, BF Ivanov, AA Kaufman, MC Kuritsyn, AV Lizunov, AA Lovell, TW Magee, RM Marrelli, L Martin, P McCollam, KJ Miller, MC Mirnov, VV Nonn, PD O'Connell, R Oliva, SP Piovesan, P Prager, SC Predebon, I Reusch, JA Sarff, JS Svidzinski, VA Tharp, TD Thomas, MA Tsidulko, YA Wyman, MD Yates, T AF Den Hartog, D. J. Ahn, J.-W. Almagri, A. F. Anderson, J. K. Beklemishev, A. D. Blair, A. P. Bonomo, F. Borchardt, M. T. Brower, D. L. Burke, D. R. Cengher, M. Chapman, B. E. Choi, S. Clayton, D. J. Cox, W. A. Combs, S. K. Craigi, D. Cummings, H. D. Davydenko, V. I. Demers, D. R. Deng, B. H. Ding, W. X. Ebrahimi, F. Ennis, D. A. Fiksel, G. Foust, C. Forest, C. B. Franz, P. Frassinetti, L. Gangadhara, S. Goetz, J. A. Harvey, R. W. Holly, D. J. Hudson, B. F. Ivanov, A. A. Kaufman, M. C. Kuritsyn, A. V. Lizunov, A. A. Lovell, T. W. Magee, R. M. Marrelli, L. Martin, P. McCollam, K. J. Miller, M. C. Mirnov, V. V. Nonn, P. D. O'Connell, R. Oliva, S. P. Piovesan, P. Prager, S. C. Predebon, I. Reusch, J. A. Sarff, J. S. Svidzinski, V. A. Tharp, T. D. Thomas, M. A. Tsidulko, Yu. A. Wyman, M. D. Yates, T. TI Recent improvements in confinement and beta in the MST reversed-field pinch SO NUCLEAR FUSION LA English DT Letter ID TOKAMAK-LIKE CONFINEMENT; TORUS AB In the general area of confinement improvement and concept advancement, recent results in the Madison Symmetric Torus (MST) reversed-field pinch (RFP) include good confinement of both thermal and large-orbit ions and near doubling of total beta to 26% with deuterium pellet injection. Current profile control enables MST to reduce stochastic transport and achieve tokamak-like confinement. In standard RFP operation, substantial MHD tearing mode activity results in stochastic transport and an energy confinement time of about I ms in MST. Application of inductive current profile control reduces MHD activity and accompanying stochasticity, improving confinement by about a factor of ten. Previous work concentrated on electron confinement in improved-confinement RFP operation. Recent work confirms that ions are also well confined, and that high beta and improved confinement can be achieved simultaneously. C1 Univ Wisconsin, Madison, WI 53706 USA. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Assoc EURATOM ENEA Fus, Consorzio RFX, Padua, Italy. Univ Calif Los Angeles, Los Angeles, CA USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Rensselaer Polytech Inst, Troy, NY USA. RP Den Hartog, DJ (reprint author), Univ Wisconsin, Madison, WI 53706 USA. EM djdenhar@wisc.edu RI Marrelli, Lionello/G-4451-2013; Beklemishev, Alexei/F-7301-2014; OI Marrelli, Lionello/0000-0001-5370-080X; Beklemishev, Alexei/0000-0001-6297-1337; Lizunov, Andrej/0000-0001-6332-4748; Ebrahimi, Fatima/0000-0003-3109-5367; Frassinetti, Lorenzo/0000-0002-9546-4494 NR 15 TC 6 Z9 6 U1 0 U2 4 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD SEP PY 2007 VL 47 IS 9 BP L17 EP L20 DI 10.1088/0029-5515/47/9/L01 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 217SY UT WOS:000249968800001 ER PT J AU Brau, JE Breidenbach, M Baltay, C Frey, RE Strom, DM AF Brau, James E. Breidenbach, Martin Baltay, Charles Frey, Raymond E. Strom, David M. TI Silicon detectors at the ILC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE silicon detectors; vertex detectors; calorimetry; linear collider AB Silicon detectors are being developed for several applications in ILC detectors. These include vertex detection, tracking, electromagnetic calorimetry, and forward detectors. The advantages of silicon detector technology have been incorporated into a full detector design, SiD (the Silicon Detector). A brief overview of this effort is presented. (c) 2007 Published by Elsevier B.V. C1 Univ Oregon, Eugene, OR 97405 USA. Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. Yale Univ, New Haven, CT 06520 USA. RP Brau, JE (reprint author), Univ Oregon, Eugene, OR 97405 USA. EM jimbrau@uoregon.edu RI Frey, Raymond/E-2830-2016 OI Frey, Raymond/0000-0003-0341-2636 NR 6 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 567 EP 571 DI 10.1016/j.nima.2007.05.247 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700004 ER PT J AU Cahn, RN AF Cahn, Robert N. TI The importance of the silicon tracker to the BaBar physics program SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA AB The silicon tracker, SVT, built for the BaBar detector has been essential to the execution of the experiment's primary goal: the measurement of time-dependent CP violation in B meson decays. Not only has it performed nearly perfectly, it has not even needed any parts replaced for radiation damage, and it has enabled the experiment to carry out a broader physics program than originally envisioned. We review briefly the SVT, its performance, and its key role in three measurements at BaBar: sin 2 beta in B J psi K-S, time-dependent CP violation in B -> K-s pi(0), and D-0-(D) over bar (0) mixing. (c) 2007 Published by Elsevier B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Cahn, RN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM rncahn@lbl.gov NR 9 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 575 EP 579 DI 10.1016/j.nima.2007.05.249 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700006 ER PT J AU Holland, SE Dawson, KS Palalo, NP Saha, J Roe, NA Wang, G AF Holland, S. E. Dawson, K. S. Palalo, N. P. Saha, J. Roe, N. A. Wang, G. TI Fabrication of back-illuminated, fully depleted charge-coupled devices SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE charge-coupled device; fully depleted; high-resistivity silicon; back illuminated; fabrication techniques ID SILICON AB We describe a fabrication strategy to produce fully depleted, back-illuminated charge-coupled devices (CCDs). Wafers are partially processed at a commercial foundry using standard processing techniques. The wafers are then thinned to the final desired thickness, and the processing steps necessary to produce back-illuminated devices are performed in our laboratory. The CCDs are then probed at wafer level, and we describe our techniques to screen for gate insulator flaws as well as defects on the back side of the wafer that are important for fully depleted devices. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Holland, SE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM seholland@lbl.gov RI Roe, Natalie/A-8798-2012; Holland, Stephen/H-7890-2013 NR 12 TC 16 Z9 16 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 653 EP 657 DI 10.1016/j.nima.2007.05.265 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700020 ER PT J AU Battaglia, M Contarato, D Glubilato, P Greiner, L Glesener, L Hooberman, B AF Battaglia, Marco Contarato, Devis Glubilato, Piero Greiner, Leo Glesener, Lindsay Hooberman, Benjamin TI A study of monolithic CMOS pixel sensors back-thinning and their application for a pixel beam telescope SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE ILC; monolithic pixel sensors ID PERFORMANCE AB This paper reports results of a detailed study of charge collection and signal-to-noise performance of CMOS monolithic pixel sensors before and after back-thinning to 50 and 40 mu m. This study shows that neither their noise nor their response to ionising particles has been degraded by the thinning process. The thinned chips have been used to build a pixel beam telescope for the ALS 1.5 GeV e(-) beam test facility. After alignment, an extrapolation resolution better than 9 mu m has been measured for a configuration of four equally spaced pixel detector planes. Published by Elsevier B.V. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Sez Padova, Ist Nazl Fis Nucl, Padua, Italy. RP Battaglia, M (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM MBattaglia@lbl.gov OI Giubilato, Piero/0000-0003-4358-5355 NR 11 TC 14 Z9 14 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 675 EP 679 DI 10.1016/j.nima.2007.05.276 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700024 ER PT J AU Stanic, S Aihara, H Barbero, M Bozek, A Browder, T Chang, P Hazumi, M Kennedy, J Martin, E Olsen, S Margan, E Mueller, J Palka, H Rosen, M Ruckman, L Trabelsi, K Tsuboyama, T Uchida, K Varner, G Yarema, R AF Stanic, S. Aihara, H. Barbero, M. Bozek, A. Browder, T. Chang, P. Hazumi, M. Kennedy, J. Martin, E. Olsen, S. Margan, E. Mueller, J. Palka, H. Rosen, M. Ruckman, L. Trabelsi, K. Tsuboyama, T. Uchida, K. Varner, G. Yarema, R. TI Recent progress in the development of a monolithic active pixel detector for a B factory SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE B factory; vertex detector; monolithic active pixel sensor; CMOS; radiation hard AB Monolithic Active Pixel Sensors (MAPS) may become the building blocks of vertex detectors at future high luminosity e(+)e(-) colliders. Requiring an active layer only a few tens of microns thick, MAPS can be thinned to similar to 50 mu m, which reduces the multiple scattering of primary particles. Deep sub-micron CMOS processes allow for small pixel size, needed for adequate single point resolution and low occupancy at a Super B factory. Major concerns with MAPS are readout speed and signal stability for large pixel arrays. Laser bench test results of a full size prototype (CAP3) with 118,784 readout pixels and a 5-deep correlated double sampling pipeline are presented. Lessons learned are applied to a design iteration and investigation of two new digital readout sensor designs, all included in the CAP4 prototype chip. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Nova Gorica, Nova Gorica 5000, Slovenia. Univ Tokyo, Bunkyo Ku, Tokyo 1130033, Japan. Univ Hawaii, Honolulu, HI 96822 USA. Polish Acad Sci, H Niewodniczanski Inst Nucl Phys, PL-31342 Krakow, Poland. Natl Taiwan Univ, Taipei 106, Taiwan. High Energy Accelerator Res Org, Tsukuba, Ibaraki, Japan. J Stefan Inst, Ljubljana 1000, Slovenia. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Stanic, S (reprint author), Univ Nova Gorica, Vipavska 13, Nova Gorica 5000, Slovenia. EM samo.stanic@p-ng.si RI Aihara, Hiroaki/F-3854-2010; OI Aihara, Hiroaki/0000-0002-1907-5964; Trabelsi, Karim/0000-0001-6567-3036 NR 9 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 680 EP 684 DI 10.1016/j.nima.2007.05.277 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700025 ER PT J AU Lipton, R AF Lipton, R. TI 3D-vertical integration of sensors and electronics SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE ILC sensors; pixel detectors; vertical integration; SOI AB Technologies are being developed which enable the vertical integration of sensors and electronics as well as multilayer electronic circuits. New thinning and wafer bonding techniques and the formation of small vias between resulting thin layers of electronics enable the design of dense integrated sensor/readout structures. We discuss candidate technologies based on SOI and bulk CMOS. A prototype 3D chip developed at Fermilab that incorporates three tiers of 0.18 mu m CMOS is described. (c) 2007 Published by Elsevier B.V. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Lipton, R (reprint author), Fermilab Natl Accelerator Lab, MS 357,POB 500, Batavia, IL 60510 USA. EM lipton@fnal.gov NR 9 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 690 EP 694 DI 10.1016/j.nima.2007.05.271 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700027 ER PT J AU Ikeda, H Arai, Y Hara, K Hayakawa, H Hirose, K Ikegami, Y Ishino, H Kasaba, Y Kawasaki, T Kohriki, T Martin, E Miyake, H Mochizuki, A Tajima, H Tajima, O Takahashi, T Takashima, T Terada, S Tomita, H Tsuboyama, T Unno, Y Ushiroda, H Varner, G AF Ikeda, H. Arai, Y. Hara, K. Hayakawa, H. Hirose, K. Ikegami, Y. Ishino, H. Kasaba, Y. Kawasaki, T. Kohriki, T. Martin, E. Miyake, H. Mochizuki, A. Tajima, H. Tajima, O. Takahashi, T. Takashima, T. Terada, S. Tomita, H. Tsuboyama, T. Unno, Y. Ushiroda, H. Varner, G. TI Deep sub-micron FD-SOI for front-end application SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE FD-SOI; deep sub-micron CMOS; CMOS analog; front-end; radiation effect AB In order to confirm benefits of a deep sub-micron FD-SOI and to identify possible issues concerning front-end circuits with the FD-SOI, we have submitted a small design to Oki Electric Industry Co., Ltd. via the multi-chip project service of VDEC, the University of Tokyo. The initial test results and future plans for development are presented. (c) 2007 Elsevier B.V. All rights reserved. C1 Japan Aerosp Explorat Agcy, ISAS, Kanagawa 2298510, Japan. High Energy Accelerator Res Org, IPNS, Tsukuba 3050801, Japan. Univ Tsukuba, Inst Pure & Appl Sci, Tsukuba 3058571, Japan. Tokyo Inst Technol, Dept Phys, Tokyo 1528551, Japan. Niigata Univ, Grad Sch Sci & Technol, Niigata 9502181, Japan. Univ Hawaii, Dept Phys & Astron, Honolulu, HI USA. Osaka Univ, Grad Sch Sci, Dept Phys, Osaka 5600043, Japan. Stanford Linear Accelerator Ctr, Stanford, CA 94307 USA. RP Ikeda, H (reprint author), Japan Aerosp Explorat Agcy, ISAS, Kanagawa 2298510, Japan. EM ikeda.hirokazu@jaxa.jp RI Ishino, Hirokazu/C-1994-2015 OI Ishino, Hirokazu/0000-0002-8623-4080 NR 5 TC 13 Z9 13 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 701 EP 705 DI 10.1016/j.nima.2007.05.280 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700029 ER PT J AU Johnson, M AF Johnson, M. CA D0 Collaboration TI Noise performance of the D0 layer 0 silicon detector SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE silicon tracker; carbon fiber; detector grounding ID READOUT AB A new inner detector called Layer 0 has been added to the existing silicon detector for the DZero colliding beams experiment [V.M. Abazoz et al., Nucl. Instr. and Meth. A 565 (2006) 463]. This detector has an all carbon fiber support structure that employs thin copper clad Kapton sheets embedded in the surface of the carbon fiber structure to improve the grounding of the structure and a readout system that fully isolates the local detector ground from the rest of the detector. Initial measurements show efficiencies greater than 90% and 0.3 ADC count (240 e) common mode contribution to the signal noise. The total detector capacitance is 24 pF so this corresponds to 2 mu V of common mode voltage. (c) 2007 Elsevier B.V. All rights reserved. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Johnson, M (reprint author), Fermilab Natl Accelerator Lab, MS 357,POB 500, Batavia, IL 60510 USA. EM mjohnson@fnal.gov NR 4 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 718 EP 722 DI 10.1016/j.nima.2007.05.281 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700032 ER PT J AU Maki, T AF Maki, Tuula CA CDF Collaboration TI Status and performance of the CDF Run II silicon detector SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE CDF; silicon detector ID EXPERIENCE AB The CDF silicon detector is one of the largest silicon detectors in operation. It has a total of 722,432 electronic channels, and it covers a sensor surface area of 6m(2). The detector has been operating reliably for five years, and it has recorded 1.5 fb(-1) of data. This article discusses experiences of operating such a large, complex system as well as the longevity of the detector. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Helsinki, Batavia, IL 60510 USA. Helsinki Inst Phys, Fermilab, Batavia, IL 60510 USA. RP Maki, T (reprint author), Univ Helsinki, MS 318,POB 500, Batavia, IL 60510 USA. EM tmaki@fnal.gov NR 12 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 723 EP 725 DI 10.1016/j.nima.2007.05.282 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700033 ER PT J AU Li, Z Abreu, M Anbinderis, P Anbinderis, T Ambrosio, NU de Boer, W Borchi, E Borer, K Bruzzi, M Buontempo, S Chen, W Cindro, V Dierlamm, A Eremin, V Gaubas, E Gorbatenko, V Grigoriev, E Hauler, F Heijne, E Heising, S Hempel, O Herzog, R Harkonen, J Ilyashenko, I Janos, S Jungermann, L Kalesinskas, V Kapturauskas, J Laiho, R Luukka, P Mandic, I De Masio, R Menichelli, D Mikuz, M Militaru, O Niinikosky, TO Shea, VO Pagano, S Paul, S Piotrzkowski, K Pretzl, K Mendes, PR Rouby, X Ruggiero, G Smith, K Sonderegger, P Sousa, P Tuominen, E Tuovinen, E Verbitskaya, E Vaitkus, J Wobst, E Zavrtanik, M AF Li, Zheng Abreu, M. Anbinderis, P. Anbinderis, T. Ambrosio, N. U. de Boer, W. Borchi, E. Borer, K. Bruzzi, M. Buontempo, S. Chen, W. Cindro, V. Dierlamm, A. Eremin, V. Gaubas, E. Gorbatenko, V. Grigoriev, E. Hauler, F. Heijne, E. Heising, S. Hempel, O. Herzog, R. Harkonen, J. Ilyashenko, I. Janos, S. Jungermann, L. Kalesinskas, V. Kapturauskas, J. Laiho, R. Luukka, P. Mandic, I. De Masio, Rita Menichelli, D. Mikuz, M. Militaru, O. Niinikosky, T. O. Shea, V. O'. Pagano, S. Paul, S. Piotrzkowski, K. Pretzl, K. Mendes, P. Rato Rouby, X. Ruggiero, G. Smith, K. Sonderegger, P. Sousa, P. Tuominen, E. Tuovinen, E. Verbitskaya, E. Vaitkus, J. Wobst, E. Zavrtanik, M. TI Cryogenic Si detectors for ultra radiation hardness in SLHC environment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE Si cryogenic detectors; CCE; current injection; trapping freeze-out; CID ID SILICON DETECTORS; TEMPERATURES; TIME AB Radiation hardness up to 10(16) n(eq)/cm(2) is required in the future HEP experiments for most inner detectors. However, 10(16) n(eq)/cm(2) fluence is well beyond the radiation tolerance of even the most advanced semiconductor detectors fabricated by commonly adopted technologies: the carrier trapping will limit the charge collection depth to an effective range of 20-30 mu m regardless of depletion depth. Significant improvement of the radiation hardness of silicon sensors has been taken place within RD39. Fortunately the cryogenic tool we have been using provides us a convenient way to solve the detector charge collection efficiency (CCE) problem at SLHC radiation level (10(16) n(eq)/cm(2)). There are two key approaches in our efforts: (1) use of the charge/current injection to manipulate the detector internal electric field in such a way that it can be depleted at a modest bias voltage at cryogenic temperature range (<= 230K); and (2) freezing out of the trapping centers that affects the CCE at cryogenic temperatures lower than that of the LN2 temperature. In our first approach, we have developed the advanced radiation hard detectors using charge or current injection, the current injected diodes (CID). In a CID, the electric field is controlled by injected current, which is limited by the space charge, yielding a nearly uniform electric field in the detector, independent of the radiation fluence. In our second approach, we have developed models of radiation-induced trapping levels and the physics of their freezing out at cryogenic temperatures. In this approach, we intend to study the trapping effect at temperatures below LN2 temperature. A freeze-out of trapping can certainly help in the development of ultra-radiation hard Si detectors for SLHC. A detector CCE measurement system using ultra-fast picosecond laser with a He cryostat has been built at CERN. This system can be used to find out the practical cryogenic temperature range that can be used to freeze out the radiation-induced trapping levels, and it is ready for measurements on extremely heavily irradiated silicon detectors. Initial data from this system will be presented. (c) 2007 Elsevier B.V. All rights reserved. C1 Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. LIP, P-1000 Lisbon, Portugal. Vilnius State Univ, Inst Mat Sci & Appl Res, LT-2040 Vilnius, Lithuania. Inst Cibernet E caianiello, I-80078 Pozzuoli, NA, Italy. Univ Karlsruhe, IEKP, D-76128 Karlsruhe, Germany. Univ Florence, Dipartimento Energet, I-50139 Florence, Italy. Univ Bern, Lab Hochenergiephys, CH-3012 Bern, Switzerland. CERN, CH-1211 Geneva, Switzerland. Brookhaven Natl Lab, Upton, NY 11973 USA. Jozef Stefan Inst, Expt Particle Phys Dept, Ljubljana 1001, Slovenia. Univ Geneva, Dept Radiol, CH-1211 Geneva, Switzerland. ILK Dresden, D-01309 Dresden, Germany. Univ Helsinki, Helsinki Inst Phys, FIN-00014 Helsinki, Finland. Univ Turku, Wihuri Phys Lab, FI-20014 Turku, Finland. Tech Univ Munich, Phys Dept E18, D-85748 Garching, Germany. Catholic Univ Louvain, B-1348 Louvain, Belgium. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. RP Li, Z (reprint author), Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. RI Zavrtanik, Marko/A-1524-2008; Rato Mendes, Pedro/F-8827-2010; Grigoriev, Eugene/K-6650-2013; Bruzzi, Mara/K-1326-2015; Pagano, Sergio/C-5332-2008; Paul, Stephan/F-7596-2015; O'Shea, Val/G-1279-2010; Verbitskaya, Elena/D-1521-2014; Paul, Stephan/K-9237-2016; Tuominen, Eija/A-5288-2017; OI Zavrtanik, Marko/0000-0001-5606-6912; Rato Mendes, Pedro/0000-0001-9929-0869; Grigoriev, Eugene/0000-0001-7235-9715; Bruzzi, Mara/0000-0001-7344-8365; Pagano, Sergio/0000-0001-6894-791X; Paul, Stephan/0000-0002-8813-0437; O'Shea, Val/0000-0001-7183-1205; Paul, Stephan/0000-0002-8813-0437; Tuominen, Eija/0000-0002-7073-7767; Abreu, Maria Conceicao/0000-0003-0093-7496; Luukka, Panja/0000-0003-2340-4641 NR 11 TC 6 Z9 6 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 EI 1872-9576 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 775 EP 781 DI 10.1016/j.nima.2007.05.296 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700044 ER PT J AU Kierstad, J Li, Z Lissauer, D Lynn, D Sernetzvidis, Y Baker, K MacFarlane, K Ely, RP Haber, C Gilchriese, M Miller, W Tuononen, A Villani, G Weber, M AF Kierstad, J. Li, Z. Lissauer, D. Lynn, D. Sernetzvidis, Y. Baker, K. MacFarlane, K. Ely, R. P. Haber, C. Gilchriese, M. Miller, W. Tuononen, Anu Villani, Giulio Weber, Marc TI Development of large area integrated silicon tracking elements for the LHC luminosity upgrade SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE tracking; position sensitive detectors; solid state detectors ID PERFORMANCE; DETECTORS; MODULES; DESIGN AB For tracking at a high luminosity upgrade of the LHC, detector granularity, scale, and radiation resistance must increase. Material burden, cost, and construction must be kept manageable. One configuration which may facilitate these requirements is to build large multi-module units referred to here as "staves". Design issues and prototyping results for staves are discussed. (c) 2007 Published by Elsevier B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Hampton Univ, Hampton, VA 23668 USA. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. RP Haber, C (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS 50B-5239,1 Cyclotron Rd, Berkeley, CA 94720 USA. EM chbaber@LBL.GOV NR 9 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 801 EP 805 DI 10.1016/j.nima.2007.05.310 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700048 ER PT J AU Metcalfe, J Dorfan, DE Grillo, AA Jones, A Martinez-McKinney, F Mekhedjian, P Mendoza, M Sadrozinski, HFW Saffier-Ewing, G Seiden, A Spencer, E Wilder, M Hackenburg, R Kierstead, J Rescia, S Cressler, JD Prakash, G Sutton, A AF Metcalfe, J. Dorfan, D. E. Grillo, A. A. Jones, A. Martinez-McKinney, F. Mekhedjian, P. Mendoza, M. Sadrozinski, H. F. -W. Saffier-Ewing, G. Seiden, A. Spencer, E. Wilder, M. Hackenburg, R. Kierstead, J. Rescia, S. Cressler, J. D. Prakash, G. Sutton, A. TI Evaluation of the radiation tolerance of several generations of SiGe heterojunction bipolar transistors under radiation exposure SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE silicon germanium; bipolar transistor; radiation effects; gain measurement ID SILICON STRIP DETECTORS; UPGRADE AB For the potential use in future high luminosity applications in high energy physics(HEP) (e.g., the large hadron collider (LHC) upgrade), we evaluated the radiation tolerance of several candidate technologies for the front-end of the readout application-specific integrated circuit (ASIC) for silicon strip detectors. The devices investigated were first, second and third-generation silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs). The DC current gain as a function of collector current was measured before and after irradiation with 24 GeV protons up to fluences of 10(16) p/cm(2) and with a Co-60 gamma source up to 100 Mrad. The analog section of an amplifier for silicon strip detectors typically has a special front transistor, chosen carefully to minimize noise and usually requiring a larger current than the other transistors, and a large number of additional transistors used in shaping sections and for signal-level discrimination. We discuss the behavior of the three generations of transistors under proton and gamma exposure, with a particular focus on issues of noise, power and radiation limitations. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, Santa Cruz, CA 95064 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA 30332 USA. RP Metcalfe, J (reprint author), Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, 1156 High Str, Santa Cruz, CA 95064 USA. EM metcalfe@unm.edu; rescia@bnl.gov; cressler@ece.gatech.edu RI Rescia, Sergio/D-8604-2011 OI Rescia, Sergio/0000-0003-2411-8903 NR 13 TC 16 Z9 17 U1 2 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 833 EP 838 DI 10.1016/j.nima.2007.05.328 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700054 ER PT J AU Bebek, C AF Bebek, Chris TI The SNAP space mission SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE SNAP; supernova; dark energy; weak lensing; CCD; HgCdTe ID PROTON RADIATION-DAMAGE; CCDS; SILICON AB The SNAP space mission concept is designed to explore dark energy with Type la supernova distance-luminosity measurements and with weak lensing angular distance correlation power spectrum. The supernova program uses photometric discovery and detailed follow-up observations of at least 2000 Type la supernovae with redshifts ranging from 0.3 to 1.7. The weak lensing program uses a deep small field survey and a shallower large field survey with photometry, position and shape measurement of several million galaxies. The instrument sits at the focus of a similar to 2-m diameter three-mirror anastigmat telescope with a 1.4 deg(2) field of view. It consists of an imager that instruments 0.7 deg(2) of the field of view, and a low-resolution spectrograph. Both the photometer and spectrograph use visible and near-infrared detectors to span the wavelength range 400-1700 nm. Wavelength is covered with two detector materials implemented with different readout architectures-CCDs for the visible and HgCdTe hybrid pixel detectors for the near-infrared. While these detector technologies are familiar in HEP experiments, they used in a very different manner, namely photon counting. The physics, architecture and characteristics of these detectors and how they are used will be presented. (c) 2007 Elsevier B.V. All rights reserved. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Bebek, C (reprint author), Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM cjbebek@lbl.gov NR 12 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 848 EP 852 DI 10.1016/j.nima.2007.05.291 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700057 ER PT J AU Takeda, S Watanabe, S Tanaka, T Nakazawa, K Takahashi, T Fukazawa, Y Yasuda, H Tajima, H Kuroda, Y Onishi, M Genba, K AF Takeda, Shin'ichiro Watanabe, Shin Tanaka, Takaaki Nakazawa, Kazuhiro Takahashi, Tadayuki Fukazawa, Yasushi Yasuda, Hajimu Tajima, Hiroyasu Kuroda, Yoshikatsu Onishi, Mitsunobu Genba, Kei TI Development of double-sided silicon strip detectors (DSSD) for a Compton telescope SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE silicon strip detector; Compton telescope; gamma-ray astronomy ID GAMMA-RAY TELESCOPE; POLARIZATION; RESOLUTION; CAMERA; ENERGY AB The low noise double-sided silicon strip detector (DSSD) technology is used to construct a next generation Compton telescope which is required to have both high-energy resolution and high-Compton reconstruction efficiency. In this paper, we present the result of a newly designed stacked DSSD module with high-energy resolution in highly packed mechanical structure. The system is designed to obtain good P-side and N-side noise performance by means of DC-coupled read-out. Since there are no decoupling capacitors in front-end electronics before the read-out ASICs, a high density stacked module with a pitch of 2 mm can be constructed. By using a prototype with four-layer of DSSDs with an area of 2.56 cm x 2.56 cm, we have succeeded to operate the system. The energy resolution at 59.5 keV is measured to be 1.6 keV (FWHM) for the P-side and 2.8 keV (FWHM) for the N-side, respectively. In addition to the DSSD used in the prototype, a 4 cm wide DSSD with a thickness of 300 mu m is also developed. With this device, an energy resolution of 1.5 keV (FWHM) was obtained. A method to model the detector energy response to properly handle split events is also discussed. (c) 2007 Published by Elsevier B.V. C1 Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Univ Tokyo, Bunkyo Ku, Tokyo 1130033, Japan. Hiroshima Univ, Higashihiroshima 7398526, Japan. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Mitsubishi Heavy Ind Co Ltd, Nagoya Guidance & Propuls Syst Works, Aichi 4858561, Japan. RP Takeda, S (reprint author), Inst Space & Astronaut Sci, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 2298510, Japan. EM takeda@astro.isas.jaxa.jp NR 16 TC 45 Z9 45 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 859 EP 865 DI 10.1016/j.nima.2007.05.305 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700059 ER PT J AU Watanabe, S Takeda, S Ishikawa, SN Odaka, H Ushio, M Tanaka, T Nakazawa, K Takahashi, T Tajima, H Fukazawa, Y Kuroda, Y Onishi, M AF Watanabe, Shin Takeda, Shin'ichiro Ishikawa, Shin-nosuke Odaka, Hirokazu Ushio, Masayoshi Tanaka, Takaaki Nakazawa, Kazuhiro Takahashi, Tadayuki Tajima, Hiroyasu Fukazawa, Yasushi Kuroda, Yoshikatsu Onishi, Mitsunobu TI Development of semiconductor imaging detectors for a Si/CdTe Compton camera SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE gamma-ray detector; Compton telescope; silicon strip detector; cadmium telluride (CdTe) ID SCHOTTKY CDTE DIODE; RAY AB Si and CdTe semiconductor imaging detectors have been developed for use in a Si/CdTe Compton camera. Based on a previous study using the first prototype of a Si/CdTe Compton camera, new detector modules have been designed to upgrade the performance of the Compton camera. As the scatter detector of the Compton camera, a stack of double-sided Si strip detector (DSSD) modules, which has four layers with a stack pitch of 2mm, was constructed. By using the stack DSSDs, an energy resolution of 1.5keV (FWHM) was achieved. For the absorber detector, the CdTe pixel detector modules were built and a CdTe pixel detector stack using these modules was also constructed. A high energy resolution (Delta E/E similar to 1%) was achieved. The improvement of the detection efficiency by stacking the modules has been confirmed by tests of the CdTe stack. Additionally, a large area CdTe imager is introduced as one application of the CdTe pixel detector module. (c) 2007 Elsevier B.V. All rights reserved. C1 Japna Aerosp Explorat Agcy, Inst Space & Astronaut Sci, Kanagawa 2298510, Japan. Univ Tokyo, Dept Phys, Tokyo 1130033, Japan. Stanford Linear Accelerator Ctr, Menlo Pk, CA USA. Hiroshima Univ, Dept Phys, Hiroshima, Japan. Mitsubishi Heavy Ind Co Ltd, Nagoya Guidance & Propuls Syst Works, Aichi 4858561, Japan. RP Watanabe, S (reprint author), Japna Aerosp Explorat Agcy, Inst Space & Astronaut Sci, 3-1-1 Yoshinodai, Kanagawa 2298510, Japan. EM watanabe@astro.isas.jaxa.jp RI Chang, Yong/B-3541-2009 NR 17 TC 14 Z9 14 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 871 EP 877 DI 10.1016/j.nima.2007.05.306 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700061 ER PT J AU Odaka, H Takeda, S Watanabe, S Ishikawa, SN Ushio, M Tanaka, T Nakazawa, K Takahashi, T Tajima, H Fukazawa, Y AF Odaka, Hirokazu Takeda, Shin'ichiro Watanabe, Shin Ishikawa, Shin-nosuke Ushio, Masayoshi Tanaka, Takaaki Nakazawa, Kazuhiro Takahashi, Tadayuki Tajima, Hiroyasu Fukazawa, Yasushi TI Performance study of Si/CdTe semiconductor Compton telescopes with Monte Carlo simulation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE gamma-ray detector; Compton telescope; Monte Carlo simulation ID GAMMA-RAY TELESCOPE; DETECTORS; ENERGY; RESOLUTION; MISSION; CAMERA AB A Compton telescope with high angular resolution and high energy resolution is a promising detector for the next generation of astrophysics space missions aiming at hard X-rays and sub-MeV/MeV gamma-rays. We have been working on a semiconductor Compton camera based on silicon and cadmium telluride (Si/CdTe Compton telescope). The soft gamma-ray detector (SGD) employs a Si/CdTe Compton camera combined with a well-type active shield. It will be mounted on the NeXT mission, proposed to be launched around 2012. One Compton camera module in the SGD will consist of 24 layers of double-sided silicon strip detectors and four layers of CdTe pixel detectors. We carried out Monte Carlo simulations to investigate the basic performance of the detector. Design parameters of devices required in the simulation, such as energy resolution and position resolution of the detector, are based on the results from our prototype detector. From the simulation using current design parameters, the detection efficiency is found to be higher than 10% at similar to 100keV and the angular resolution to be 9 degrees and 4.4 degrees at 120keV and 330keV, respectively. The effects of changing the design parameters are also discussed. (c) 2007 Published by Elsevier B.V. C1 JAXA, Inst Space & Astronaut Sci, Dept High Energy Astrophys, Sagamihara, Kanagawa 2298510, Japan. Univ Tokyo, Grad Sch Sci, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. Hiroshima Univ, Dept Phys Sci, Higashihiroshima 7398526, Japan. RP Odaka, H (reprint author), JAXA, Inst Space & Astronaut Sci, Dept High Energy Astrophys, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 2298510, Japan. EM odaka@astro.isas.jaxa.jp NR 20 TC 17 Z9 17 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 878 EP 885 DI 10.1016/j.nima.2007.05.293 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700062 ER PT J AU Amman, M Luke, PN Boggs, SE AF Amman, M. Luke, P. N. Boggs, S. E. TI Amorphous-semiconductor-contact germanium-based detectors for gamma-ray imaging and spectroscopy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE gamma-ray imaging; gamma-ray spectroscopy; Germanium detector; orthogonal strip; position sensing ID BLOCKING CONTACTS; STRIP DETECTORS; GE DETECTORS AB Germanium-based detectors are the standard technology used for gamma-ray spectroscopy when high efficiency and excellent energy resolution are desired. By dividing the electrical contacts on these detectors into segments, the locations of the gamma-ray interaction events within the detectors can be determined as well as the deposited energies. This enables simultaneous gamma-ray imaging and spectroscopy and leads to applications in the areas of astronomy, nuclear physics, environmental remediation, nuclear nonproliferation, and homeland security. Producing the fine-pitched electrode segmentation often required for imaging has been problematic in the past. To address this issue, we have developed an amorphous-semiconductor contact technology. Using this technology, fully passivated detectors with closely spaced contacts can be produced using a simple fabrication process. The current state of the amorphous-semiconductor contact technology and the challenges that remain are given in this paper. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Nat Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Amman, M (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Nat Lab, Berkeley, CA 94720 USA. EM Mark_Amman@lbl.gov RI Boggs, Steven/E-4170-2015 OI Boggs, Steven/0000-0001-9567-4224 NR 18 TC 26 Z9 26 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 886 EP 890 DI 10.1016/j.nima.2007.05.307 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700063 ER PT J AU Denes, P Bussat, JM Lee, Z Radmillovic, V AF Denes, P. Bussat, J.-M. Lee, Z. Radmillovic, V. TI Active Pixel Sensors for electron microscopy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE electron microscopy; Active Pixel Sensor ID DETECTOR AB The technology used for monolithic CMOS imagers, popular for cell phone cameras and other photographic applications, has been explored for charged particle tracking by the high-energy physics community for several years. This technology also lends itself to certain imaging detector applications in electron microscopy. We have been developing such detectors for several years at Lawrence Berkeley National Laboratory, and we and others have shown that this technology can offer excellent point-spread function, direct detection and high readout speed. In this paper, we describe some of the design constraints peculiar to electron microscopy and summarize where such detectors could play a useful role. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Denes, P (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Engn, Berkeley, CA 94720 USA. EM pdenes@lbl.gov RI Lee, Zonghoon/G-1474-2011 OI Lee, Zonghoon/0000-0003-3246-4072 NR 14 TC 16 Z9 16 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 891 EP 894 DI 10.1016/j.nima.2007.05.308 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700064 ER PT J AU Cornell, EW Fadeyev, V Haber, C Jin, J Nordmeyer, R Golden, M AF Cornell, E. W. Fadeyev, V. Haber, C. Jin, J. Nordmeyer, R. Golden, M. TI Using optical metrology to reconstruct sound recordings SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Symposium on Development and Application of Semiconductor Tracking Detectors CY SEP 11-15, 2006 CL Carmel, CA DE tracking; optical metrology; linage processing; audio records; sound restoration AB Prior to 1950 nearly all sound recordings were made on mechanical media such as wax, foil, shellac, lacquer, and plastic. Some of these older recordings contain material of great historical value or interest but are damaged, decaying, or now considered too delicate to play. Archives seek to preserve and also create broad access to their collections. An ongoing effort at Berkeley Lab has applied methods of optical metrology and image processing to reconstruct sound stored on these mechanical carriers. This approach was inspired by the use of precision optical metrology to align and fabricate silicon tracking arrays for high-energy physics experiments and by track finding and fitting data analysis methods. The technology has matured to the point that an optical metrology system for sound restoration has been designed and built for the Library of Congress. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Fadeyev, V (reprint author), Univ Calif Santa Cruz, SCIPP, 1156 High St, Santa Cruz, CA 95064 USA. EM vf@scipp.ucsc.edu NR 5 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD SEP 1 PY 2007 VL 579 IS 2 BP 901 EP 904 DI 10.1016/j.nima.2007.05.316 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 212NS UT WOS:000249604700066 ER PT J AU Grubel, G Stephenson, GB Gutt, C Sinn, H Tschentscher, T AF Gruebel, G. Stephenson, G. B. Gutt, C. Sinn, H. Tschentscher, Th. TI XPCS at the European X-ray free electron laser facility SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE x-ray photon correlation spectroscopy (XPCS); X-ray free electron laser (XFEL); X-ray Scattering; X-ray speckles; Time domain dynamics; Pump-probe studies ID INTENSITY FLUCTUATION SPECTROSCOPY; PHOTON-CORRELATION SPECTROSCOPY; LIQUID-GLASS TRANSITION; SMECTIC-A FILMS; LIGHT-SCATTERING; DYNAMICS; B2O3; SURFACES; RANGE AB The European X-ray free electron laser source (XFEL) will provide highly brilliant (B > 10(33) ph/s/mm(2)/mrad(2)/0.1% bw) and coherent X-ray beams. The pulse structure and the unprecedented brightness will allow one for the first time to study fast dynamics in the time domain, thus giving direct access to the dynamic response function S(Q, t), instead of S(Q, omega), which is of central importance for a variety of phenomena such as fast non-equilibrium dynamics initiated, e.g. by a short pump pulse. X-ray photon correlation spectroscopy (XPCS) measures the temporal changes in speckle patterns produced when coherent light is scattered by a disordered system and therefore allows to measure S(Q, t). This paper summarizes important aspects of the scientific case for an XPCS instrument at the planned XFEL. Novel XPCS set-ups are illustrated. (c) 2007 Elsevier B.V. All rights reserved. C1 Hasylab, DESY, D-22607 Hamburg, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. RP Grubel, G (reprint author), Hasylab, DESY, Notkerstr 85, D-22607 Hamburg, Germany. EM Gerhard.gruebel@desy.de RI Gutt, Christian/H-9846-2012; Gutt, Christian/F-6337-2013 NR 38 TC 47 Z9 47 U1 1 U2 26 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD SEP PY 2007 VL 262 IS 2 BP 357 EP 367 DI 10.1016/j.nimb.2007.05.015 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 211QE UT WOS:000249537600027 ER PT J AU Daniel, AV Goodin, C Li, K Ramayya, AV Stone, NJ Hwang, J Hamilton, JH Stone, JR Luo, Y Rasmussen, JO Stoyer, MA Zhu, SJ Ter-Akopian, GM Lee, IY AF Daniel, A. V. Goodin, C. Li, K. Ramayya, A. V. Stone, N. J. Hwang, Jx. Hamilton, J. H. Stone, J. R. Luo, Yx Rasmussen, J. O. Stoyer, M. A. Zhu, S. J. Ter-Akopian, G. M. Lee, I. Y. TI Technique for measuring angular correlations and g-factors of excited states with large multi-detector arrays: An application to neutron rich nuclei produced by the spontaneous fission of Cf-252 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE g-Factor; Cf-252; Angular correlation ID MAGNETIC-MOMENTS; GAMMA-RAYS; FRAGMENTS AB Triple coincidences between prompt gamma-rays emitted in the spontaneous fission of Cf-252 were measured with Gammasphere. These data are used to measure the angular correlation of cascades of gamma-rays from excited states of neutron rich fission fragments stopped in an unmagnetized iron foil. The hyperfine fields in the iron lattice cause attenuations of the angular correlations between gamma-rays emitted from the excited states which have sufficiently long lifetimes. This attenuation is measured and used to calculate the g-factors of excited states in many neutron rich nuclei. (c) 2007 Elsevier B.V. All rights reserved. C1 Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. JINR, Flerov Lab Nucl React, Dubna, Russia. Joint Inst Heavy Ion Res, Oak Ridge, TN 37830 USA. Univ Oxford, Dept Phys, Oxford OX1 3PU, England. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Tsing Hua Univ, Dept Phys, Beijing 100084, Peoples R China. RP Goodin, C (reprint author), Vanderbilt Univ, Dept Phys, 221 Kirkland Hall, Nashville, TN 37235 USA. EM christopher.tgoodin@vandderbilt.edu NR 15 TC 32 Z9 34 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD SEP PY 2007 VL 262 IS 2 BP 399 EP 406 DI 10.1016/j.nimb.2007.06.008 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 211QE UT WOS:000249537600032 ER PT J AU Iancu, E McLerran, L AF Iancu, E. McLerran, L. TI Liouville field theory for gluon saturation in QCD at high energy SO NUCLEAR PHYSICS A LA English DT Article ID COLOR GLASS CONDENSATE; SMALL-X; LARGE NUCLEI; RENORMALIZATION-GROUP; CONFORMAL-INVARIANCE; KOVCHEGOV EQUATION; FRONT PROPAGATION; MULTICOLOR QCD; POMERON LOOPS; WAVE-FUNCTION AB We argue that quantum Liouville field theory supplemented with a suitable source term is the effective theory which describes the short-range correlations of the gluon saturation momentum in the two-dimensional impact-parameter space, at sufficiently high energy and for a large number of colors. This is motivated by recent developments concerning the stochastic aspects of the high-energy evolution in QCD, together with the manifest scale invariance of the respective evolution equations and general considerations on the uncertainty principle. The source term explicitly breaks down the conformal symmetry of the (pure) Liouville action, thus introducing a physical mass scale in the problem which is identified with the average saturation momentum. We construct this source term for the case of a homogeneous distribution and show that this leads to an interesting theory: the relevant correlation functions are ultraviolet finite (and not just renormalizable) when computed in perturbation theory, due to mutual cancellations of the tadpole divergences. Possible generalizations to inhomogeneous source terms are briefly discussed. (C) 2007 Elsevier B.V. All rights reserved. C1 CEA Saclay, DSM, SPhT, Serv Phys Theor, F-91191 Gif Sur Yvette, France. RIKEN, Brookhaven Natl Lab, BNL Res Ctr, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Iancu, E (reprint author), CEA Saclay, DSM, SPhT, Serv Phys Theor, F-91191 Gif Sur Yvette, France. EM iancu@dsm-mail.cea.fr; mclerran@quark.phy.bnl.gov NR 75 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD SEP 1 PY 2007 VL 793 BP 96 EP 127 DI 10.1016/j.nuclphysa.2007.06.010 PG 32 WC Physics, Nuclear SC Physics GA 218OW UT WOS:000250025800007 ER PT J AU Schafer, A Wang, XN Zhang, BW AF Schaefer, Andreas Wang, Xin-Nian Zhang, Ben-Wei TI Multiple parton scattering in nuclei: Quark-quark scattering SO NUCLEAR PHYSICS A LA English DT Article DE jet quenching; modified fragmentation; parton energy loss ID RADIATIVE ENERGY-LOSS; MODIFIED FRAGMENTATION FUNCTIONS; GLUON PLASMA; QCD; COLLISIONS; BREMSSTRAHLUNG; DISTRIBUTIONS; ENVIRONMENT; OPACITY AB Modifications to quark and antiquark fragmentation functions due to quark-quark (antiquark) double scattering in nuclear medium are studied systematically up to order O(alpha(2)(s)) in deeply inelastic scattering (DIS) off nuclear targets. At the order O(alpha(2)(s)), twist-four contributions from quark-quark (antiquark) rescattering also exhibit the Landau-Pomeranchuk-Migdal (LPM) interference feature similar to gluon bremsstrahlung induced by multiple parton scattering. Compared to quark-gluon scattering, the modification, which is dominated by t-channel quark-quark (antiquark) scattering, is only smaller by a factor of C-F/C-A = 4/9 times the ratio of quark and gluon distributions in the medium. Such a modification is not negligible for realistic kinematics and finite medium size. The modifications to quark (antiquark) fragmentation functions from quark-antiquark annihilation processes are shown to be determined by the antiquark (quark) distribution density in the medium. The asymmetry in quark and antiquark distributions in nuclei will lead to different modifications of quark and antiquark fragmentation functions inside a nucleus, which qualitatively explains the experimentally observed flavor dependence of the leading hadron suppression in semi-inclusive DIS off nuclear targets. The quark-antiquark annihilation processes also mix quark and gluon fragmentation functions in the large fractional momentum region, leading to a flavor dependence of jet quenching in heavy-ion collisions. (C) 2007 Elsevier B.V. All rights reserved. C1 Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Texas A&M Univ, Cyclotron Inst, Dept Phys, College Stn, TX 77843 USA. Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China. RP Wang, XN (reprint author), Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany. EM xnwang@lbl.gov OI Wang, Xin-Nian/0000-0002-9734-9967 NR 53 TC 18 Z9 18 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 EI 1873-1554 J9 NUCL PHYS A JI Nucl. Phys. A PD SEP 1 PY 2007 VL 793 BP 128 EP 170 DI 10.1016/j.nuclphysa.2007.06.009 PG 43 WC Physics, Nuclear SC Physics GA 218OW UT WOS:000250025800008 ER PT J AU Kloosterman, JL Ougouag, AA AF Kloosterman, J. L. Ougouag, A. A. TI Comparison and extension of Dancoff factors for pebble-bed reactors SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID SIMULATION; SPHERES AB A method is developed for the computation of infinite-medium Dancoff factors for spherical kernels with a stochastic packing as used in high- temperature reactors. The method is used to compute Dancoff factors that are then compared to those obtained by four preexisting methods from the literature. The older methods assume either infinitesimally small kernels with a random distribution, or finite kernels with some assumptions. In the new method, the infinite-medium Dancoff factor is calculated rigorously by numerically integrating the Dancoff factor of two adjacent finite-size kernels over their surfaces and relative positions. It turns out that for practical pebble-bed fuel designs, as currently envisioned, all four methods give results accurate (i.e., compatible with one another) within 2%, but that larger deviations are observed for extreme cases (either at high or low dilution). A Monte Carlo program, named INTRAPEB, was written to calculate the average value and the space dependency of the Dancoff factor of one single fuel pebble, as well as the angular distribution of neutrons escaping the pebble. For the Dancoff factor, the analytical results from literature agree very well with the new computational approach. However, for a cubic packing of particles, as is usually modeled in MCNP calculations, a larger Dancoff factor is found for the pebble. The angular distribution of neutrons escaping from the moderator zone of a pebble is much more forwardly peaked than the cosine angular distribution assumed in the derivation of the analytical methods. If the previously developed analytical methods need improvement, this could be achieved by using a more forwardly peaked neutron distribution. A second program, named PEBDAN, was written to calculate the average value and the space dependency of the interpebble Dancoff factor (the probability that a neutron escaping from the fuel zone of a pebble crosses a fuel particle in another pebble) and the pebble-pebble Dancoff factor (the probability that a neutron escaping from the fuel zone of a pebble crosses the fuel zone of another pebble). In this program, the coordinates of the pebbles in a randomly packed bed are determined, after which the Dancoff factors are calculated using a Monte Carlo ray-tracing method. The packing distribution obtained in this code reproduces the principal features of experimental data; however, the predicted radial porosity profile of the packed bed displays less-pronounced oscillations (i.e., lower peaks) and a slightly larger average porosity value. Because of the larger first-flight escape probability of neutrons, the Dancoff factors drop several tens of percent along the inner and outer reflector of the core. C1 Delft Univ Technol, NL-2629 JB Delft, Netherlands. Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Kloosterman, JL (reprint author), Delft Univ Technol, Mekelweg 15, NL-2629 JB Delft, Netherlands. EM J.L.Kloosterman@tudelft.nl RI Ougouag, Abderrafi/A-9499-2009 OI Ougouag, Abderrafi/0000-0003-4436-380X NR 25 TC 14 Z9 14 U1 0 U2 2 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD SEP PY 2007 VL 157 IS 1 BP 16 EP 29 PG 14 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 209ON UT WOS:000249398000002 ER PT J AU Dashdorj, D Mitchell, GE Becker, JA Agvaanluvsan, U Bernstein, LA Younes, W Garrett, PE Chadwick, MB Devlin, M Fotiades, N Kawano, T Nelson, RO AF Dashdorj, D. Mitchell, G. E. Becker, J. A. Agvaanluvsan, U. Bernstein, L. A. Younes, W. Garrett, P. E. Chadwick, M. B. Devlin, M. Fotiades, N. Kawano, T. Nelson, R. O. TI Gamma-ray production cross sections in multiple channels for neutron-induced reaction on (48)Ti for E(n)=1 to 200 MeV SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID MODEL AB Prompt gamma-ray production cross sections were measured on a (48)Ti sample for incident neutron energies from 1 to 200 MeV Partial gamma-ray cross sections for transitions in (45-48)Ti, (45-48)Sc, and (43-45)Ca were determined. The observation of about 130 transitions from 11 different isotopes in the present work provides a demanding test of reaction model calculations, and is the first study in this mass region to extract partial gamma-ray cross sections for many different reaction channels over a wide range of incident neutron energies. The neutrons were produced by the Los Alamos National Laboratory spallation neutron source located at the Los Alamos Neutron Science Center/Weapons Neutron Research facility. The prompt-reaction gamma rays were detected with the large-scale Compton-suppressed GErmanium Array for Neutron Induced Excitations (GEANIE). Event neutron energies were determined by the time-of-flight technique. The gamma-ray excitation functions were converted to partial gamma-ray cross sections and then compared with model calculations using the enhanced GNASH reaction code. Compound nuclear, preequilibrium emission, and direct reaction mechanisms are included. Overall, the model calculations of the partial gamma-ray cross sections are in good agreement with measured values. C1 N Carolina State Univ, Raleigh, NC 27695 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Triangle Univ Nucl Lab, Durham, NC 27708 USA. Univ Guelph, Guelph, ON N1G 2W1, Canada. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dashdorj, D (reprint author), N Carolina State Univ, Raleigh, NC 27695 USA. EM dashdorj1@llnl.gov RI Devlin, Matthew/B-5089-2013 OI Devlin, Matthew/0000-0002-6948-2154 NR 19 TC 7 Z9 7 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD SEP PY 2007 VL 157 IS 1 BP 65 EP 77 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 209ON UT WOS:000249398000005 ER PT J AU Longhurst, GR AF Longhurst, Glen R. TI Introduction to the beryllium technology special issue SO NUCLEAR TECHNOLOGY LA English DT Editorial Material C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Longhurst, GR (reprint author), Idaho Natl Lab, Idaho Falls, ID 83415 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD SEP PY 2007 VL 159 IS 3 BP 227 EP 227 PG 1 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 204RG UT WOS:000249061100001 ER PT J AU Matthern, GE Yancey, NA Knudson, DL Hanson, DI AF Matthern, Gretchen E. Yancey, Neal A. Knudson, Darrel L. Hanson, Duane I. TI Use of a paraffin-based grout to stabilize buried beryllium and other wastes SO NUCLEAR TECHNOLOGY LA English DT Article DE beryllium; WAXFIX; waste ID SOIL AB The long-term durability of WAXFIX, a paraffin-based grout, was evaluated for in situ grouting of activated beryllium wastes in the subsurface disposal area (SDA), a radioactive landfill at the Radioactive Waste Management Complex, part of the Idaho National Laboratory (INL). The evaluation considered radiological and biological mechanisms that could degrade the grout using data from an extensive literature search and previous tests of in situ grouting at the INL. Conservative radioactive doses for WAXFIX were calculated from the "hottest" (i.e., highest-activity) Advanced Test Reactor beryllium block in the SDA. These results indicate that WAXFIX would not experience extensive radiation damage for many hundreds of years. Calculation of radiation-induced hydrogen generation in WAXFIX indicated that grout physical performance should not be reduced beyond the effects of radiation dose on the molecular structure. Degradation of a paraffin-based grout by microorganisms in the SDA is possible and perhaps likely, but the rate of degradation will be at a slower rate than found in the literature reviewed. The calculations showed the outer 0.46-m (18-in.) layer of each monolith, which represents the minimum expected distance to the beryllium block, was calculated to require 1000 to 3600yr to be consumed. The existing data and estimations of biodegradation and radiolysis rates for WAXFIX/paraffin do not indicate any immediate problems with the use of WAXFIX for grouting beryllium or other wastes in the SDA. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Matthern, GE (reprint author), Idaho Natl Lab, POB 1625, Idaho Falls, ID 83415 USA. EM Gretchen.Matthem@inl.gov NR 28 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD SEP PY 2007 VL 159 IS 3 BP 250 EP 255 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 204RG UT WOS:000249061100006 ER PT J AU Hetmaniuk, U AF Hetmaniuk, U. TI A Rayleigh quotient minimization algorithm based on algebraic multigrid SO NUMERICAL LINEAR ALGEBRA WITH APPLICATIONS LA English DT Article DE symmetric generalized eigenvalue problem; preconditioned eigensolver; algebraic multigrid ID EIGENVALUE PROBLEMS; DAVIDSON AB This paper presents a new algebraic extension of the Rayleigh quotient multigrid (RQMG) minimization algorithm to compute the smallest eigenpairs of a symmetric positive definite pencil (A, M). Earlier versions of RQMG minimize the Rayleigh quotient over a hierarchy of geometric grids. We replace the geometric mesh information with the algebraic information defined by an algebraic multigrid preconditioner. At each level, we minimize the Rayleigh quotient with a block preconditioned algorithm. Numerical experiments illustrate the efficiency of this new algorithm to compute several eigenpairs. Copyright (c) 2007 John Wiley & Sons, Ltd. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hetmaniuk, U (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM ulhetma@sandia.gov NR 30 TC 7 Z9 7 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 1070-5325 J9 NUMER LINEAR ALGEBR JI Numer. Linear Algebr. Appl. PD SEP PY 2007 VL 14 IS 7 BP 563 EP 580 DI 10.1002/nla.545 PG 18 WC Mathematics, Applied; Mathematics SC Mathematics GA 210UC UT WOS:000249480100003 ER PT J AU Scott, DE Casey, ED Donovan, MF Lynch, TK AF Scott, David E. Casey, Erin D. Donovan, Michele F. Lynch, Tracy K. TI Amphibian lipid levels at metamorphosis correlate to post-metamorphic terrestrial survival SO OECOLOGIA LA English DT Article DE carryover effects; fitness correlates; lipids; postmetamorphic survival; trade-offs ID COMPLEX LIFE-CYCLES; ENERGY ALLOCATION; AMBYSTOMA-OPACUM; LARVAL DENSITY; JUVENILE PERFORMANCE; FIELD ENCLOSURES; WATER ECONOMY; MARINE MUSSEL; BODY-SIZE; HISTORY AB In organisms that have complex life cycles, factors in the larval environment may affect both larval and adult traits. For amphibians, the postmetamorphic transition from the aquatic environment to terrestrial habitat may be a period of high juvenile mortality. We hypothesized that lipid stores at metamorphosis may affect an animal's success during this critical transition period. We examined variation in total lipid levels among years and sites in recently metamorphosed individuals of two pond-breeding salamander species, the marbled salamander (Ambystoma opacum) and the mole salamander (A. talpoideum), with limited data for one anuran species (southern leopard frog, Rana sphenocephala). Lipid levels were allometrically related to body size and ranged from 1.9 to 23.8% of body dry mass. The two salamander species differed in lipid allocation patterns, with A. opacum apportioning a higher percentage of total lipid reserves into fat bodies than A. talpoideum. Species differences in lipid allocation patterns may primarily reflect that large metamorphs will mature as one-year olds, and, regardless of species, will alter lipid compartmentalization accordingly. We used mark-recapture data obtained at drift fences encircling breeding ponds for 13 A. opacum cohorts to estimate the proportion of postmetamorphic individuals that survived to breed (age 1-4) and the mean age at first reproduction. Regression models indicated that size-corrected lipid level at metamorphosis (i.e., lipid residuals), and to a lesser extent rainfall following metamorphosis, was positively related to adult survival. Snout-vent length at metamorphosis was negatively related to age at first reproduction. We suggest that lipid stores at metamorphosis are vital to juvenile survival in the months following the transition from aquatic to terrestrial habitat, and that a trade-off shaped by postmetamorphic selection in the terrestrial habitat exists between allocation to energy stores versus structural growth in the larval environment. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Scott, DE (reprint author), Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. EM scott@srel.edu NR 74 TC 53 Z9 54 U1 5 U2 32 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 0029-8549 J9 OECOLOGIA JI Oecologia PD SEP PY 2007 VL 153 IS 3 BP 521 EP 532 DI 10.1007/s00442-007-0755-6 PG 12 WC Ecology SC Environmental Sciences & Ecology GA 201DP UT WOS:000248812000003 PM 17530291 ER PT J AU Mozyrsky, D Martin, I AF Mozyrsky, D. Martin, I. TI Efficiency of thin film photocells SO OPTICS COMMUNICATIONS LA English DT Article AB We propose a new concept for the design of high-efficiency photocells based on ultra-thin (submicron) semiconductor films of controlled thickness. Using a microscopic model of a thin dielectric layer interacting with incident electromagnetic radiation we evaluate the efficiency of conversion of solar radiation into the electric power. We determine the optimal range of parameters which maximize the efficiency of such photovoltaic element. (c) 2007 Elsevier B.V. All rights reserved. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Mozyrsky, D (reprint author), Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. EM mozyrsky@lanl.gov OI Mozyrsky, Dima/0000-0001-5305-4617 NR 7 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 EI 1873-0310 J9 OPT COMMUN JI Opt. Commun. PD SEP 1 PY 2007 VL 277 IS 1 BP 109 EP 113 DI 10.1016/j.optcom.2007.04.062 PG 5 WC Optics SC Optics GA 197LE UT WOS:000248556100018 ER PT J AU Bouhelier, A Ignatovich, F Bruyant, A Huang, C Francs, GCD Weeber, JC Dereux, A Wiederrecht, GP Novotny, L AF Bouhelier, A. Ignatovich, F. Bruyant, A. Huang, C. Francs, G. Colas des Weeber, J.-C. Dereux, A. Wiederrecht, G. P. Novotny, L. TI Surface plasmon interference excited by tightly focused laser beams SO OPTICS LETTERS LA English DT Article ID POLARITONS; EXCITATION; FILMS AB We show that interfering surface plasmon polaritons can be excited with a focused laser beam at normal incidence to a plane metal film. No protrusions or holes are needed in this excitation scheme. Depending on the axial position of the focus, the intensity distribution on the metal surface is either dominated by interferences between counterpropagating plasmons or by a two-lobe pattern characteristic of localized surface plasmon excitation. Our experiments can be accurately explained by use of the angular spectrum representation and provide a simple means for locally exciting standing surface plasmon polaritons. (c) 2007 Optical Society of America. C1 Univ Bourgogne, CNRS, UMR, Inst Carnot Bourgogne, F-21078 Dijon, France. Univ Rochester, Inst Opt, Rochester, NY 14627 USA. Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA. RP Bouhelier, A (reprint author), Univ Bourgogne, CNRS, UMR, Inst Carnot Bourgogne, F-21078 Dijon, France. EM alexandre.bouhelier@u-bourgogne.fr RI Bouhelier, Alexandre/A-1960-2010; Colas des Francs, Gerard/C-9400-2009; Dereux, Alain/K-8754-2016 OI Colas des Francs, Gerard/0000-0002-5097-7317; Dereux, Alain/0000-0002-9009-114X NR 20 TC 85 Z9 87 U1 1 U2 15 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD SEP 1 PY 2007 VL 32 IS 17 BP 2535 EP 2537 DI 10.1364/OL.32.002535 PG 3 WC Optics SC Optics GA 216VV UT WOS:000249908000024 PM 17767296 ER PT J AU Xiong, YL AF Xiong, Yongliang TI Hydrothermal thallium mineralization up to 300 degrees C: A thermodynamic approach SO ORE GEOLOGY REVIEWS LA English DT Review DE thallium; thermodynamic proper-ties; hydrothermal; aqueous speciation; solubility; specific interaction theory; isocoulombic approach ID TL-AU DEPOSIT; CRYSTAL-STRUCTURE; NEW-ZEALAND; ELEVATED-TEMPERATURES; THEORETICAL PREDICTION; AQUEOUS-SOLUTION; EDENHARTERITE TLPBAS3S6; EQUILIBRIUM-CONSTANTS; HYDROXIDE COMPLEXES; BINNTAL SWITZERLAND AB Thermodynamic properties of solid and aqueous thallium species are essential in understanding of the hydrothermal thallium mineralization. However, these data are largely lacking. To remedy this situation, complete thermodynamic properties including entropy, heat capacity, enthalpy and free energy for a number of ternary and quaternary thallium-bearing sulfosalts, and secondary thallium minerals formed in supergene environments such as lanmuchangite, are estimated according to the revised estimation methods proposed in this study. The reliability of these estimation methods is demonstrated by the good agreement between the estimated values and the measured values for a number of sulfosalts with known thermodynamic properties. In the aspect of aqueous thallium species, the stability constants involving several thallium complexes including TIHCO degrees(3), TICO3-, TISO4-, TIHS degrees, 3 3 4 TIOH degrees and TlAc degrees at 25 degrees C are critically evaluated at first. Then, their stability constants at elevated temperatures up to 300 degrees C at vapor saturation pressures are obtained based on the isocoulombic approach. Using the data from these two aspects, one may be able to assess quantitatively the solubility of thallium-bearing minerals and the relative importance of various thallium aqueous species in transport of thallium up to 300 degrees C. In the relatively oxidizing environments where sulfate dominates, the results from this study suggest that free thallium ion (Tl+) is important at 100 degrees C from pH 1 to pH 9. At 200 degrees C, TI+ is the dominant species from pH 1 to pH 7. At 300 degrees C, TI+ and TICI degrees predominate from pH I to pH 5. At higher pHs, TISO4-, TIHCO degrees(3), TlCO3- and TIOH degrees become increasingly important. In the reducing environments where sulfide dominates, Tl+ is important in acidic pH region, whereas TIHS degrees is dominant in neutral to alkaline pH range, from 100 degrees C to 200 degrees C. At 300 degrees C, Tl+ and TICI degrees are dominant species in acidic pH region, and TIHS degrees predominates in the pH range from similar to 5.5 to similar to 9.5. At higher pHs, TICO3- and TIOH degrees are dominant. Thermodynamic calculations suggest that lorandite is the solubility-controlling phase in low temperature (similar to 100 degrees C to 200 degrees C) hydrothermal fluids. Thallium constituents in form of solid solutions in sulfides, for instance, as Tl0.5As0.5S2 in pyrite, may be the solubility-controlling phase for thallium in hydrothermal solutions up to 300 degrees C or higher rich in reduced sulfur. Solubilities of both carlinite alone and lorandite in equilibrium with orpiment have strong dependence on pH. Solubility calculations in combination with field observations provide insight into the formation of hydrothermal thallium mineralization, especially independent thallium deposits, and therefore may provide valuable guidance for exploration for thallium mineralization. The most favorable combination conditions for thallium mineralization are (1) leaching thallium from source rocks by acidic hydrothermal fluids at higher temperatures (up to 250 degrees C) at the early stage, and (2) subsequent neutralization of the acidic hydrothermal fluids by host rocks such as carbonate rocks at the late stage, resulting in the formation of thallium mineralization at low temperatures (around 100 degrees C). (c) 2006 Elsevier B.V. All rights reserved. C1 Univ Idaho, Dept Geol Sci, Moscow, ID 83844 USA. RP Xiong, YL (reprint author), Sandia Natl Labs, Carlsbad Programs Grp, 4100 Natl Parks Highway, Carlsbad, NM 88220 USA. EM yxiong@sandia.gov NR 144 TC 19 Z9 20 U1 2 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-1368 J9 ORE GEOL REV JI Ore Geol. Rev. PD SEP PY 2007 VL 32 IS 1-2 BP 291 EP 313 DI 10.1016/j.oregeorev.2006.10.003 PG 23 WC Geology; Mineralogy; Mining & Mineral Processing SC Geology; Mineralogy; Mining & Mineral Processing GA 216DU UT WOS:000249859200012 ER PT J AU Gropp, W Thakur, R AF Gropp, William Thakur, Rajeev TI Thread-safety in an MPI implementation: Requirements and analysis SO PARALLEL COMPUTING LA English DT Article; Proceedings Paper CT 13th EuroPVM/MPI Conference CY SEP 17-20, 2006 CL Bonn, GERMANY DE message-passing interface (MPI); thread-safety; MPI implementation; multithreaded programming AB The MPI-2 Standard has carefully specified the interaction between MPI and user-created threads. The goal of this specification is to allow users to write multithreaded MPI programs while also allowing MPI implementations to deliver high performance. However, a simple reading of the thread-safety specification does not reveal what its implications are for an implementation and what implementers must be aware (and careful) of. In this paper, we describe and analyze what the MPI Standard says about thread-safety and what it implies for an implementation. We classify the MPI functions based on their thread-safety requirements and discuss several issues to consider when implementing thread-safety in MPI. We use the example of generating new context ids (required for creating new communicators) to demonstrate how a simple solution for the single-threaded case does not naturally extend to the multithreaded case and how a naive thread-safe algorithm can be expensive. We then present an algorithm for generating context ids that works efficiently in both single-threaded and multithreaded cases. (C) 2007 Elsevier B.V. All rights reserved. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Gropp, W (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM gropp@mcs.anl.gov OI Gropp, William/0000-0003-2905-3029 NR 14 TC 14 Z9 15 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8191 J9 PARALLEL COMPUT JI Parallel Comput. PD SEP PY 2007 VL 33 IS 9 BP 595 EP 604 DI 10.1016/j.parco.2007.07.002 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA 223JK UT WOS:000250366000002 ER PT J AU Buntings, D Mercier, G Gropp, W AF Buntings, Darius Mercier, Guillaume Gropp, William TI Implementation and evaluation of shared-memory communication and synchronization operations in MPICH2 using the Nemesis communication subsystem SO PARALLEL COMPUTING LA English DT Article; Proceedings Paper CT 13th EuroPVM/MPI Conference CY SEP 17-20, 2006 CL Bonn, GERMANY DE parallel computing; message passing; MPI; MPI implementation; communication subsystem; shared-memory ID ALGORITHMS AB This paper presents the implementation of MPICH2 over the Nemesis communication subsystem and the evaluation of its shared-memory performance. We describe design issues as well as some of the optimization techniques we employed. We conducted a performance evaluation over shared memory using microbenchmarks. The evaluation shows that MPICH2 Nemesis has very low communication overhead, making it suitable for smaller-grained applications. (C) 2007 Elsevier B.V. All rights reserved. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Univ Bordeaux 1, INRIA Futurs, LaBRI, F-33405 Talence, France. RP Buntings, D (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM buntings@mcs.anl.gov; mercierg@mcs.anl.gov; gropp@mcs.anl.gov OI Gropp, William/0000-0003-2905-3029 NR 17 TC 25 Z9 25 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8191 J9 PARALLEL COMPUT JI Parallel Comput. PD SEP PY 2007 VL 33 IS 9 BP 634 EP 644 DI 10.1016/j.parco.2007.06.003 PG 11 WC Computer Science, Theory & Methods SC Computer Science GA 223JK UT WOS:000250366000006 ER PT J AU Tsap, LV Duchaineau, M Goldgof, DB Shin, MC AF Tsap, Leonid V. Duchaineau, Mark Goldgof, Dmitry B. Shin, Min C. TI Data-driven feature modeling, recognition and analysis in a discovery of supersonic cracks in multimillion-atom simulations SO PATTERN RECOGNITION LA English DT Article DE data-driven; feature modeling (analysis, extraction, recognition); image motion analysis; physics-based; supersonic cracks; molecular dynamics; atomic simulation; nanoscale analysis ID EDGE-DETECTION ALGORITHMS; EXTRACTION AB This paper presents a new, automated image- and feature-based pipeline of analysis algorithms to elucidate and quantify a discovery regarding supersonic cracks made using large-scale molecular dynamics computations. The first computational confirmation of supersonic cracks was made in recent years, along with the discovery of a two-step, discrete process of increasing crack velocity through the nucleation of a transonic daughter crack and the later nucleation of a supersonic granddaughter crack. This discovery was facilitated by the work presented here. The algorithm pipeline includes modeling, recognition and motion analysis of both the front most crack tips and the more subtle secondary wavefronts from the slower ancestor cracks. The algorithms employed include line extraction from Canny edge maps, feature modeling based on physical properties, and subsequent tracking of primary and secondary wavefronts. The model embeds anticipated propagation properties (physics-based framework) and adapts to changes in the data for unexpected aspects (data-driven modeling). This process is completely automated; it runs in real time on three different 834-frame sequences using 40 250 MHz processors. Results supporting the discovery of the two-step transition to supersonic crack propagation in bilayer materials are presented in terms of both feature tracking and velocity analysis. (c) 2007 Pattern Recognition Society. Published by Elsevier Ltd. All rights reserved. C1 Lawrence Livermore Natl Lab, Syst Res Grp, Dept Elect Engn, Livermore, CA 94551 USA. Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. Univ S Florida, Dept Comp Sci & Engn, Tampa, FL 33620 USA. Univ N Carolina, Dept Comp Sci, Charlotte, NC 28223 USA. RP Tsap, LV (reprint author), Lawrence Livermore Natl Lab, Syst Res Grp, Dept Elect Engn, POB 808,L-229, Livermore, CA 94551 USA. EM tsap@llnl.gov; duchaine@llnl.gov; goldgof@bigpine.csee.usf.edu; mcshin@uncc.edu NR 22 TC 0 Z9 0 U1 0 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0031-3203 EI 1873-5142 J9 PATTERN RECOGN JI Pattern Recognit. PD SEP PY 2007 VL 40 IS 9 BP 2400 EP 2407 DI 10.1016/j.patcog.2006.12.027 PG 8 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 174HG UT WOS:000246932200004 ER PT J AU Moreno, NO Thompson, JD Taylor, RD Sarrao, JL AF Moreno, N. O. Thompson, J. D. Taylor, R. D. Sarrao, J. L. TI Spin glass state in (Fe05Ni0.5TiO3)-Ni-. polycrystal SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT At the Frontiers of Condensed Matter III Workshop CY DEC 11-15, 2006 CL Buenos Aires, ARGENTINA SP CNEA, Phys Dept DE spin-glass; AC susceptibility; Fe0.5Ni0.5TiO3 AB The spin glass Fe0.5Ni0.5TiO3 has been studied by DC/AC susceptibility as well as Mossbauier spectroscopy measurements. The data show a transition front a paramagnetic to an anti ferromagnetic state at T-N = 116K and a reentrant spin-glass behavior is observed below T-RSG = 60 K. (c) 2007 Published by Elsevier B.V. C1 Univ Fed Sergipe, Dept Fis, BR-49100000 Sao Cristovao, SE, Brazil. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Moreno, NO (reprint author), Univ Fed Sergipe, Dept Fis, BR-49100000 Sao Cristovao, SE, Brazil. EM nomoreno@fisica.ufs.br RI Moreno, Nelson/H-1708-2012 OI Moreno, Nelson/0000-0002-1672-4340 NR 7 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD SEP 1 PY 2007 VL 398 IS 2 BP 245 EP 247 DI 10.1016/j.physb.2007.04.025 PG 3 WC Physics, Condensed Matter SC Physics GA 205XD UT WOS:000249147100018 ER PT J AU Duque, JGS Urbano, RR Venegas, PA Pagliuso, PG Rettori, C Fisk, Z Oseroff, SB AF Duque, J. G. S. Urbano, R. R. Venegas, P. A. Pagliuso, P. G. Rettori, C. Fisk, Z. Oseroff, S. B. TI Exchange interaction effects in the ESR spectra of Eu2+ in LaB6 SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT At the Frontiers of Condensed Matter III Workshop CY DEC 11-15, 2006 CL Buenos Aires, ARGENTINA SP CNEA, Phys Dept DE Eu2+; ESR; LaB6; Dysonian resonance ID ELECTRON-SPIN-RESONANCE; INTERMETALLIC COMPOUNDS; POLARIZATION; ABSORPTION; METALS; ND3+; GD3+ AB The electron spin resonance (ESR) spectra of Eu2+ (4f(7), S = 7/2) in LaB6 single crystal show a single Dysonian resonance for the localized Eu2+ magnetic moments. It is shown that the Eu2+ ions are covalent exchange coupled to the (B) 2p-like host conduction electrons. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Estadual Campinas, UNICAMP, Inst Fis, IFGW, BR-13083970 Campinas, SP, Brazil. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Estadual Paulista, Dept Fis, BR-17033360 Bauru, SP, Brazil. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. San Diego State Univ, San Diego, CA 92182 USA. RP Duque, JGS (reprint author), Univ Estadual Campinas, UNICAMP, Inst Fis, IFGW, CP 6165, BR-13083970 Campinas, SP, Brazil. EM jduque@ifi.unicamp.br RI Rettori, Carlos/C-3966-2012; Pagliuso, Pascoal/C-9169-2012; Urbano, Ricardo/F-5017-2012; Venegas, Pablo/J-2108-2012; Inst. of Physics, Gleb Wataghin/A-9780-2017 OI Rettori, Carlos/0000-0001-6692-7915; NR 18 TC 1 Z9 1 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD SEP 1 PY 2007 VL 398 IS 2 BP 424 EP 426 DI 10.1016/j.physb.2007.04.053 PG 3 WC Physics, Condensed Matter SC Physics GA 205XD UT WOS:000249147100061 ER PT J AU Abrikosov, AA AF Abrikosov, A. A. TI Theory of an unusual metal-insulator transition in layered high-T-c cuprates SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY AB A brief description of the theory of the metal-insulator transition in layered cuprates and some unusual phenomena in both phases is presented. (c) 2007 Published by Elsevier B.V. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RP Abrikosov, AA (reprint author), Argonne Natl Lab, Div Sci Mat, 9700 S Cass Ave, Argonne, IL 60439 USA. EM abrikosov@anl.gov NR 10 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 1 EP 2 DI 10.1016/j.physc.2007.03.009 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500003 ER PT J AU Maier, TA Jarrell, MS Scalapino, DJ AF Maier, T. A. Jarrell, M. S. Scalapino, D. J. TI Understanding high-temperature superconductors with quantum cluster theories SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY ID CORRELATED ELECTRON-SYSTEMS; PARTICLE INTERACTION; HUBBARD-MODEL; STATE AB Quantum cluster theories are a set of approaches for the theory of correlated and disordered lattice systems, which treat correlations within the cluster explicitly, and correlations at longer length scales either perturbatively or within a mean-field approximation. These methods become exact when the cluster size diverges, and most recover the corresponding (dynamical) mean-field approximation when the cluster size becomes one. Here we will review systematic dynamical cluster simulations of the two-dimensional Hubbard model, that display phenomena remarkably similar to those found in the cuprates, including antiferromagnetism, superconductivity and pseudogap behavior. We will then discuss results for the structure of the pairing mechanism in this model, obtained from a combination of dynamical cluster results and diagrammatic techniques. (c) 2007 Elsevier B.V. All rights reserved. C1 Ctr Nanophase Mat Sci, Comp Sci & Math Div, Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Cincinnati, Dept Phys, Cincinnati, OH 45221 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. RP Maier, TA (reprint author), Ctr Nanophase Mat Sci, Comp Sci & Math Div, Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM maierta@ornl.gov RI Maier, Thomas/F-6759-2012 OI Maier, Thomas/0000-0002-1424-9996 NR 25 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 13 EP 19 DI 10.1016/j.physc.2007.03.260 PN 1 PG 7 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500006 ER PT J AU Dai, P Wilson, SD Li, S AF Dai, Pengcheng Wilson, Stephen D. Li, Shiliang TI Evolution of spin excitations in electron-doped Pr0.88LaCe0.12CUO4-delta SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE electron-doped high-Tc superconductors; magnetic excitations ID TRANSITION-TEMPERATURE SUPERCONDUCTOR; MAGNETIC EXCITATIONS; YBA2CU3O6+X; STATE AB We briefly review results of recent neutron scattering experiments designed to probe the evolution of antiferromagnetic (AF) order and spin dynamics in the electron-doped Pr0.88LaCe0.12CuO4-delta as the system is tuned from its as-grown nonsuperconducting AF state into an optimally doped superconductor (T-c = 24 K) without static AF order. For under doped materials, a quasi-two-dimensional spin-density-wave was found to coexist with three-dimensional AF order and superconductivity. In addition, the low energy spin excitations follow Bose statistics. In the case of optimally doped material, we have discovered a magnetic resonance intimately related to superconductivity analogous to the resonance in hole-doped materials. On the other hand, the low energy spin excitations have very weak temperature dependence and do not follow Bose statistics, in sharp contrast to the as-grown nonsuperconducting materials. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Ctr Neutron Scattering, Oak Ridge, TN 37831 USA. RP Dai, P (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. EM daip@ornl.gov RI Li, Shiliang/B-9379-2009; Dai, Pengcheng /C-9171-2012 OI Dai, Pengcheng /0000-0002-6088-3170 NR 22 TC 0 Z9 0 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 52 EP 55 DI 10.1016/j.physc.2007.03.090 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500014 ER PT J AU Samuely, P Szabo, P Pribulova, Z Angst, M Bud'ko, SL Canfield, PC Klein, T Lyard, L Marcus, J Marcenat, C Kang, BW Kim, HJ Lee, HS Lee, HK Lee, SI AF Samuely, P. Szabo, P. Pribulova, Z. Angst, M. Bud'ko, S. L. Canfield, P. C. Klein, T. Lyard, L. Marcus, J. Marcenat, C. Kang, B. W. Kim, H.-J. Lee, H.-S. Lee, H.-K. Lee, S. I. TI Aluminum and carbon substitution in MgB2. Electron doping and scattering effects SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE two-band/two-gap superconductivity; electron doping; scattering effects AB The point-contact spectroscopy is used to address the evolution of two superconducting energy gaps in the Al- and C-doped magnesium diboride polycrystals and single crystals with T-c's from 39 to 22 K prepared by different techniques. The obtained evolution of two gaps does not show any anomalous behavior but can be consistently described by the combination of the (prevailing) band filling effect and a (minor) increased interband scattering as proposed by Kortus et al. [Kortus et al., Phys. Rev. Lett. 94 (2005) 027002]. The approaching of two gaps is stronger in the Al-doped systems but interband scattering is still not large enough to merge two gaps. The full merging can expected only for higher dopings with T-c's below 10-15 K. In-magnetic-field measurements are used to analyze the intraband scatterings introduced by these two substitutions. It is shown that the carbon doping introduces significant disorder mainly by decreasing the diffusion coefficient in the pi band while the Al substitution leaves the samples in the clean limit. (c) 2007 Elsevier B.V. All rights reserved. C1 Safarik Univ, Slovak Acad Sci, Ctr Low Temp Phys, IEP & FS,Ctr Excellence, SK-04001 Kosice, Slovakia. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. CNRS, Etud Proprietes Elect Solides Lab, F-38054 Grenoble, France. DRFMC, CEA, F-38054 Grenoble, France. Pohang Univ Sci & Technol, Pohang 790784, South Korea. RP Samuely, P (reprint author), Safarik Univ, Slovak Acad Sci, Ctr Low Temp Phys, IEP & FS,Ctr Excellence, Watsonova 47, SK-04001 Kosice, Slovakia. EM samuely@saske.sk RI Angst, Manuel/I-4380-2012; Canfield, Paul/H-2698-2014 OI Angst, Manuel/0000-0001-8892-7019; NR 18 TC 4 Z9 4 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 84 EP 88 DI 10.1016/j.physc.2007.03.161 PN 1 PG 5 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500024 ER PT J AU Lang, M de Souza, M Bruhl, A Strack, C Wolf, B Schlueter, JA Muller, J Schweitzer, D AF Lang, Michael de Souza, Mariano Bruehl, Andreas Strack, Christian Wolf, Bernd Schlueter, John A. Mueller, Jens Schweitzer, Dieter TI Comparative transport and thermal expansion studies on quasi-2D organic superconductors close to the metal-to-insulator transition SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE organic superconductors; Mott metal-insulator transition; thermal expansion; resistivity ID CONDUCTOR; PRESSURE AB A deuterated crystal Of kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Br has been studied by high-resolution thermal expansion and resistivity measurements. This crystal is found to be situated close to the critical pressure which marks the end point of the first-order metal-to-insulator transition in the generalized phase diagram of kappa-(BEDT-TTF)(2)X. The in-plane a-axis expansion coefficient reveals a distinct anomaly at 30 K which is attributed to the anomalous lattice response upon approaching the first-order metal-to-insulator transition. This feature is shown to be intimately related to the anomaly at T* approximate to 40 K for the hydrogenated salt. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Frankfurt, Inst Phys, D-60438 Frankfurt, Germany. Argonne Natl Lab, Chem & Mat Sci Div, Argonne, IL 60439 USA. Max Planck Inst Chem Phys Stoffe, D-01187 Dresden, Germany. Univ Stuttgart, Inst Phys, D-70550 Stuttgart, Germany. RP Lang, M (reprint author), Univ Frankfurt, Inst Phys, FOR 412, D-60438 Frankfurt, Germany. EM milang@physik.uni-frankfurt.de RI de Souza, Mariano/F-5219-2012 OI de Souza, Mariano/0000-0002-2466-3402 NR 15 TC 4 Z9 4 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 129 EP 132 DI 10.1016/j.physc.2007.03.167 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500036 ER PT J AU Park, T Sarrao, JL Thompson, JD AF Park, Tuson Sarrao, J. L. Thompson, J. D. TI New quantum phase in the heavy fermion superconductor CeRhIn5 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE quantum phase transition; CeRhIn5; heavy fermion superconductor; hidden magnetism ID ANTIFERROMAGNETIC ORDER; PRESSURE; FIELD AB Pressure dependence on the specific heat of CeRhIn5 has been studied for magnetic field perpendicular to the ab-plane. Similar to the field parallel to the ab-plane [T. Park et al., Nature 440 (2006) 65], magnetic field reveals hidden magnetism in the mixed superconducting state above 1.75 GPa where antiferromagnetism disappears at zero field. The specific heat anomaly at T-c is initially suppressed with increasing field, but becomes enhanced with further increasing field, indicating that the nature of the superconducting (SC) transition may have changed from second to first order. Together with the coexisting phase of the field-induced magnetism and superconductivity, the first-order like SC transition in CeRhIn5 may provide insight to the inhomogeneous SC state (or FFLO state) observed in CeCoIn5. (c) 2007 Elsevier B.V. All rights reserved. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Park, T (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM tuson@lanl.gov RI Park, Tuson/A-1520-2012 NR 16 TC 1 Z9 1 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 137 EP 140 DI 10.1016/j.physc.2007.04.138 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500038 ER PT J AU Wakimoto, S Yamada, K Tranquada, JM Frost, CD Swainson, I Birgeneau, RJ AF Wakimoto, S. Yamada, K. Tranquada, J. M. Frost, C. D. Swainson, I. Birgeneau, R. J. TI Magnetic excitations in overdoped La2-xSrxCuO4 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE high-T-c superconductivity; LSCO; spin excitation; neutron scattering ID HIGH-TEMPERATURE SUPERCONDUCTORS; TRANSITION-TEMPERATURE; PHASE-SEPARATION; STRIPES AB Spin excitations of overcloped La2-xSrxCuO4 (0.25 <= x <= 0.30) have been studied by neutron scattering utilizing triple-axis and time-of-flight spectrometers. Low-energy excitation spectra (omega <= 10 meV) for all of the superconducting samples show a maximum around omega = 6 meV with a maximum value of dynamic spin susceptibility chi ''(omega) that decreases linearly with T-c as doping increases. The magnetic scattering cross section finally disappears at x = 0.30, coincident with the disappearance of bulk superconductivity. Time-of-flight measurements for x = 0.25 and 0.30 show markedly suppressed magnetic scattering intensities at intermediate energies (20 <= omega <= 80 meV) in contrast to those of the stripe-ordered La1.875Ba0.125CuO4, which shows large spectral weight near the saddle point of the "hour-glass" shape dispersion. These facts imply a cooperative correlation between the dynamic incommensurate state and the superconductivity. (c) 2007 Elsevier B.V. All rights reserved. C1 Japan Atom Energy Agcy, Tokai, Ibaraki 3191195, Japan. Tohoku Univ, Mat Res Inst, Sendai, Miyagi 9808577, Japan. Condensed Matter Phys & Mat Sci Dept, Brookhaven Natl Lab, Upton, NY 11973 USA. Rutherford Appleton Lab, JSIS Facil, Didcot OX11 0QX, Oxon, England. CNR, Chalk River, ON K0J 1J0, Canada. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Yamada, K (reprint author), Japan Atom Energy Agcy, Tokai, Ibaraki 3191195, Japan. EM kyamada@imr.tohoku.ac.jp RI Tranquada, John/A-9832-2009; Yamada, Kazuyoshi/C-2728-2009 OI Tranquada, John/0000-0003-4984-8857; NR 19 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 166 EP 169 DI 10.1016/j.physc.2007.03.306 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500047 ER PT J AU Hucker, M Gu, GD Tranquada, JM von Zimmermann, M Klauss, HH Curro, NJ Braden, M Buchner, B AF Huecker, M. Gu, G. D. Tranquada, J. M. von Zimmermann, M. Klauss, H. -H. Curro, N. J. Braden, M. Buechner, B. TI Coupling of stripes to lattice distortions in cuprates and nickelates SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE superconductivity; stripe order; lattice symmetry ID COPPER-OXIDE SUPERCONDUCTORS; PHASE-DIAGRAM; ANTIFERROMAGNETIC ORDER; TRANSITION-TEMPERATURE; DOPED LA2-XSRXCUO4; EXCITATIONS; HOLES AB In recent X-ray diffraction experiments on orthorhombic nickelates, we have observed a significant coupling between the stripe correlations and the lattice distortion. In particular, the diagonal charge stripes of this insulating material exhibit a preferred orientation parallel to the orthorhombic a-axis, similar to the diagonal spin stripes in La2-xSrxCuO4 below the metal-insulator transition. In the light of this finding, we draw a comparison between the lightly doped parts of the phase diagrams of La2-xSrxCuO4 with low-temperature orthorhombic (LTO) structure, and La1.8-xEu0.2SrxCuO4 with low-temperature tetragonal (LT-F) structure. In La1.8-xEu0.2SrxCuO4, a local minimum in the Sr dependence of the LTO/LTT transition temperature, as well as reduced spin-glass transition temperatures, may be indicators for the presence of diagonal charge correlations. Above the metal-insulator transition the LTT phase is suited to pin parallel stripes, while below that transition the LTT phase seems instead to compete with the formation of diagonal stripes. (c) 2007 Elsevier B.V. All rights reserved. C1 Condensed Matter Phys & Mat Sci Dept, Brookhaven Natl Lab, Upton, NY 11973 USA. Hamburger Synchrontronstschlungslab HASYLAB, D-22603 Hamburg, Germany. TU Braunschweig, Inst Phys Kondensierten Mat, D-38106 Braunschweig, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Cologne, Inst Phys 2, D-50937 Cologne, Germany. Leibniz Inst Solid State & Mat Res, IFW Dresden, D-01171 Dresden, Germany. RP Hucker, M (reprint author), Condensed Matter Phys & Mat Sci Dept, Brookhaven Natl Lab, Upton, NY 11973 USA. EM huecker@bnl.gov RI Tranquada, John/A-9832-2009; Klauss, Hans-Henning/G-4743-2010; Gu, Genda/D-5410-2013; Buchner, Bernd/E-2437-2016; Curro, Nicholas/D-3413-2009 OI Tranquada, John/0000-0003-4984-8857; Gu, Genda/0000-0002-9886-3255; Buchner, Bernd/0000-0002-3886-2680; Curro, Nicholas/0000-0001-7829-0237 NR 35 TC 25 Z9 25 U1 2 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 170 EP 173 DI 10.1016/j.physc.2007.03.003 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500048 ER PT J AU Graf, J Gweon, GH Lanzara, A AF Graf, J. Gweon, G.-H. Lanzara, A. TI Universal waterfall-like feature in the spectral function of high temperature superconductors SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE cuprates; ARPES; strongly correlated electron systems; high temperature superconductors ID ANGLE-RESOLVED PHOTOEMISSION; CUPRATE SUPERCONDUCTORS; DISPERSION; SURFACE; ENERGY; OXIDES; STATE; HOLE AB By performing high resolution angle resolved photoemission spectroscopy (ARPES) experiments on four different families of p-type cuprates, over an energy range much bigger than investigated before, we report the discovery of a universal high energy anomaly in the spectral function. This anomaly is characterized by the presence of two new high energy scales E-1 = 0.35-0.45 eV and E-2 = 0.8-0.9 eV and the pinning of the main ARPES spectral function along the boundary of a diamond in the momentum space. This anomaly unveils a missing link between the doped oxygen holes and the quasiparticles, providing a full range of relevant interactions to the high T-c problem. Published by Elsevier B.V. C1 Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. RP Lanzara, A (reprint author), Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. EM alanzara@lbl.gov NR 37 TC 11 Z9 11 U1 1 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 194 EP 197 DI 10.1016/j.physc.2007.03.005 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500054 ER PT J AU Park, WK Greene, LH Sarrao, JL Thompson, JD AF Park, Wan Kyu Greene, Laura H. Sarrao, John L. Thompson, Joe D. TI Andreev reflection spectroscopy of the heavy-fermion superconductor CeCoIn5 along three different crystallographic orientations SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE heavy-fermion superconductor; CeCoIn5; andreev reflection; blonder-tinkham-klapwijk model; point-contact spectroscopy ID UNCONVENTIONAL SUPERCONDUCTIVITY; CUPRATE SUPERCONDUCTORS; SYMMETRY; STATE AB Andreev reflection spectroscopy has been performed on the heavy-fermion superconductor (HFS) CeCoIn5 single crystals along three different crystallographic orientations, (0 0 1), (1 1 0), and (1 0 0), using Au tips as counter-electrodes. Dynamic conductance spectra are reproducible over wide temperature ranges and consistent with each other, ensuring the spectroscopic nature. Features common to all directions are: (i) asymmetric behaviors of the background conductance, which we attribute to the emerging coherent heavy-fermion liquid; (ii) energy scales (similar to 1 meV) for conductance enhancement due to Andreev reflection; and (iii) magnitudes of enhanced zero-bias conductance (10-13%). These values are an order of magnitude smaller than the predicted value by the Blonder-Tinkham-Klapwijk (BTK) theory, but comparable to those for other HFSs. Using the d-wave BTK model, we obtain an energy gap of similar to 460 mu eV. However, it is found that extended BTK models considering the mismatch in Fermi surface parameters do not account for our data completely, which we attribute to the shift of spectral weight to low energy as well as to the suppressed Andreev reflection. A qualitative comparison of the conductance spectra with calculated curves shows a consistency with d(x2-y2) symmetry, providing the first spectroscopic evidence for the order parameter symmetry and resolving the controversy over the location of the line nodes. (C) 2007 Elsevier B.V. All rights reserved. C1 Univ Illinois, Dept Phys, Frederick Seitz Mat Res Lab, Urbana, IL 61801 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Park, WK (reprint author), Univ Illinois, Dept Phys, Frederick Seitz Mat Res Lab, Urbana, IL 61801 USA. EM wkpark@uiuc.edu NR 27 TC 9 Z9 9 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 206 EP 209 DI 10.1016/j.physc.2007.03.007 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500057 ER PT J AU Egami, T AF Egami, T. TI Lattice effects in cuprates SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE phonons; electron-phonon coupling; neutron scattering; charge inhomogeneity ID HIGH-TEMPERATURE SUPERCONDUCTORS AB We describe the fine details of the dependence of the dispersion of the Cu-O bond-stretching phonon in YBa2Cu3O6+x on temperature and composition, recently determined by inelastic neutron scattering. The results suggest the presence of a localized phonon mode above the pseudogap temperature, which softens at lower temperatures. Its implications and possible role in the mechanism of high-temperature superconductivity are discussed. (C) 2007 Elsevier B.V. All rights reserved. C1 Univ Tennessee, Dept Mat Sci & Engn, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37853 USA. RP Egami, T (reprint author), Univ Tennessee, Dept Mat Sci & Engn, Dept Phys & Astron, Knoxville, TN 37996 USA. EM egami@utk.edu NR 15 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 267 EP 270 DI 10.1016/j.physc.2007.03.086 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500074 ER PT J AU Matias, V Gibbons, BJ Feldmann, DM AF Matias, Vladimir Gibbons, Brady J. Feldmann, D. Matthew TI Coated conductors textured by ion-beam assisted deposition SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE high temperature superconductors; coated conductors; IBAD ID FILMS; MGO; TEMPLATES AB We review the progress on ion-beam assisted deposition (I BAD) textured superconducting tapes. Over the past 15 years there has been much work worldwide on Y2O3-stabilized ZrO2 (YSZ) textured templates for deposition of HTS. More recently Gd2Zr2O7 textured templates have replaced YSZ in Japan. -At Los Alamos National Laboratory in the USA we have developed a process for continuous texturing of MgO on metal tapes, with subsequent buffer layer deposition, and REBaCuO pulsed-laser deposition (PLD). We discuss the critical issues being researched in our coated conductor architecture. IBAD-MgO is an extremely fast process, but requires smooth surfaces over long lengths, which is achieved in our laboratory by electropolishing of metal alloy tapes. The progress to date has demonstrated that IBAD-MgO texture can develop in less than 1 s. Under optimized processing conditions the in-plane texture full-width half-maximum for the MgO is less than 5 degrees and less than 2 degrees for out-of-plane texture. In the YBCO layer this improves to an in-plane texture of less than 2 degrees and 1 degrees out-of-plane. At this level of alignment critical currents are no longer limited by the film grain boundaries. Critical currents for YBCO layers deposited continuously by PLD on the IBAD-MgO templates have been steadily increasing over the last five years, and have been demonstrated to exceed 500 A/cm-width. An important remaining issue for coated conductors is the decrease in J(c), with thickness of the HTS film. (C) 2007 Elsevier B.V. All rights reserved. C1 Los Alamos Natl Lab, Supercond Technol Ctr, Los Alamos, NM 87545 USA. Univ Wisconsin, Ctr Appl Superconduct, Madison, WI 53706 USA. RP Matias, V (reprint author), Los Alamos Natl Lab, Supercond Technol Ctr, Los Alamos, NM 87545 USA. EM vlado@lanl.gov NR 12 TC 22 Z9 22 U1 0 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 312 EP 315 DI 10.1016/j.physc.2007.03.357 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500086 ER PT J AU Logvenov, G Sveklo, I Bozovic, I AF Logvenov, G. Sveklo, I. Bozovic, I. TI Combinatorial molecular beam epitaxy of La2-xSrxCuO4+delta SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE molecular beam epitaxy; high temperature superconductors; combinatorial library ID THIN-FILMS; TEMPERATURE; STRAIN AB Using combinatorial molecular beam epitaxy (COMBE), we have deposited combinatorial libraries of La2-xSrxCuO4 (LSCO) single-crystal thin films with different Sr content. A study of these LSCO libraries allows for a systematic evaluation of the COMBE method. We have also developed and tested a multiple-probe set-up for transport measurements that allowed us to measure within one week the R(T) dependence in more than 2000 different samples (pixels in the ID combinatorial library of LSCO). We also studied in detail the dependence of the crystal structure (specifically, the c-axis lattice constant) on the Sr content and on the type of epitaxial strain (compressive versus tensile). For the films grown on LaSrAlO4 substrates, we found that the c-axis lattice constant of LSCO films decreased as Sr content was increased. This we attribute to the reduction in the epitaxial strain, since the in-plane lattice constant of LSCO decreases as Sr doping is increased. We also discuss the effect of the (small) nonlinearity of beam profile. Published by Elsevier B.V. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Bialystok, Inst Expt Phys, PL-15424 Bialystok, Poland. RP Logvenov, G (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. EM glogveno@bnl.gov NR 6 TC 4 Z9 5 U1 5 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 416 EP 419 DI 10.1016/j.physc.2007.03.408 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500125 ER PT J AU Nunner, TS Hirschfeld, PJ Andersen, BM Melikyan, A McElroy, K AF Nunner, T. S. Hirschfeld, P. J. Andersen, B. M. Melikyan, A. McElroy, K. TI Signatures of modulated pair interaction in cuprate superconductors SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE pair mechanism; d-wave superconductivity; disorder; STM; theory ID BI2SR2CACU2O8+DELTA AB Recent low-temperature scanning tunnelling spectroscopy experiments oil the surface of Bi2Sr2CaCu2O8+x have revealed a strong positive correlation between the position of localized resonances at -960 meV identified with interstitial oxygen dopants and the size of the local spectral gap. We review efforts to understand these correlations within a model where the dopants modulate the pair interaction on an atomic scale. We provide further evidence for this model by comparing the correlations between the dopants and the local density of states with experimental results. (C) 2007 Elsevier B.V. All rights reserved. C1 Free Univ Berlin, Inst Theoret Phys, D-1000 Berlin, Germany. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Nunner, TS (reprint author), Free Univ Berlin, Inst Theoret Phys, Arnimallee 14, D-1000 Berlin, Germany. EM nunner@physik.fu-berlin.de RI Hirschfeld, Peter /A-6402-2010; mcelroy, kyle/D-1816-2013; Andersen, Brian /M-4671-2014 OI Andersen, Brian /0000-0002-9786-7553 NR 13 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 446 EP 449 DI 10.1016/j.physc.2007.03.116 PN 1 PG 4 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500139 ER PT J AU Phillips, NE Oeschler, N Fisher, RA Gordon, JE Foo, ML Cava, RJ AF Phillips, N. E. Oeschler, N. Fisher, R. A. Gordon, J. E. Foo, M.-L. Cava, R. J. TI Specific-heat of Na0.35CoO2 center dot 1.3H(2)O: Effects of sample age and pair breaking on two-gap superconductivity SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE cobaltate; superconductivity; pair breaking; two-gap; sample-dependent AB Specific-heat measurements on Na0.35CoO2 center dot 1.3H(2)O show an evolution of the superconductivity, and its ultimate disappearance, with increasing sample age. An increase in pair breaking action, which occurs preferentially in an electron band with a small energy-gap, produces a shift in the relative contributions of two electron bands to the superconducting condensation. The similarity of the time scale for these changes to that recently reported for structural changes suggests a relation between the two effects and a basis for understanding the sample dependence of the properties of this material in general. Published by Elsevier B.V. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Amherst Coll, Dept Phys, Amherst, MA 01002 USA. Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. RP Phillips, NE (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. EM nephill@cchem.berkeley.edu RI Foo, Maw Lin/H-9273-2012 NR 3 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 473 EP 474 DI 10.1016/j.physc.2007.03.039 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500151 ER PT J AU Lorenz, B Perner, O Eckert, J Chu, CW AF Lorenz, B. Perner, O. Eckert, J. Chu, C. W. TI Superconducting gaps of nanocrystalline MgB2 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE nanocrystalline MgB2; superconducting gap structure; specific heat AB The superconducting gap structure of nanocrystalline MgB2 is investigated by heat capacity measurements. It is shown that the larger sigma-gap decreases as a consequence of defects and impurities introduced by the specifics of the high-energy ball milling synthesis process. This explains the reduction of the critical temperature. The smaller pi-gap slightly increases as compared to bulk MgB2 indicating an enhanced interband scattering in the nanocrystalline samples. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Houston, TCS, Dept Phys, Houston, TX 77205 USA. Inst Met Mat, IFW Dresden, D-01069 Dresden, Germany. Tech Univ Darmstadt, FB 11 Mat & Geowissenschaften, D-64287 Darmstadt, Germany. Lawrence Berkeley Natl Lab, Berkeley, CA 94702 USA. Hong Kong Univ Sci & Technol, Hong Kong, Peoples R China. RP Lorenz, B (reprint author), Univ Houston, TCS, Dept Phys, Houston, TX 77205 USA. EM blorenz@uh.edu NR 6 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 553 EP 554 DI 10.1016/j.physc.2007.03.253 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500189 ER PT J AU Ferrando, V Pallecchi, I Malagoll, A Putti, M Xi, XX Varlamov, AA Koshelev, AE Ferdeghini, C AF Ferrando, V. Pallecchi, I. Malagoll, A. Putti, M. Xi, X. X. Varlamov, A. A. Koshelev, A. E. Ferdeghini, C. TI Paraconductivity of MgB2 thin films SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY AB Paraconductivity of MgB2 has been measured in homogeneous thin films grown by Hybrid physical chemical vapor deposition. In order to reduce the possible effects of spatial inhomogeneities, stripes of different widths were cut on the films. We measured several samples with different resistivity values; after subtracting the normal state resistivity, paraconductivity appears to be of the same order of magnitude in all the samples. The dependence on the reduced temperature epsilon = ln(T/Tc) is discussed and compared with the existing models. (c) 2007 Elsevier B.V. All rights reserved. C1 CNR, INFM, LAMIA, I-16146 Genoa, Italy. Penn State Univ, University Pk, PA 16802 USA. CNR, INFM, I-00133 Rome, Italy. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Ferrando, V (reprint author), CNR, INFM, LAMIA, Via Dodecaneso 33, I-16146 Genoa, Italy. EM ferrandov@ge.infm.it RI Putti, Marina/N-2844-2014; Koshelev, Alexei/K-3971-2013; OI Putti, Marina/0000-0002-4529-1708; Koshelev, Alexei/0000-0002-1167-5906; FERDEGHINI, CARLO/0000-0003-0323-7719 NR 8 TC 1 Z9 1 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 608 EP 609 DI 10.1016/j.physc.2007.04.116 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500215 ER PT J AU Bergk, B Ignatchik, O Bianchi, AD Jaeckel, M Wosnitza, J Perenboom, J Canfield, PC AF Bergk, B. Ignatchik, O. Bianchi, A. D. Jaeckel, M. Wosnitza, J. Perenboom, J. Canfield, P. C. TI Determination of the superconducting gap of LuNi2B2C SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE borocarbides; de Haas-van Alphen effect; superconducting gap function ID YNI2B2C AB We present de Haas-van Alphen (dHvA) measurements of the nonmagnetic borocarbide LuNi2B2C. In the superconducting state below the upper critical field, B-c2, the dHvA signal shows an additional damping. For some field orientations we observe a very strong damping close to B-c2 and only a very weak effect at lower fields in the superconducting state. We discuss the origin of the different dampings and their relation to the superconducting gap. (c) 2007 Elsevier B.V. All rights reserved. C1 Tech Univ Dresden, Inst Festkorperphys, D-01062 Dresden, Germany. Forschungzentrum Dresden Rossendorf, Hochfeld Magnetlabor Dresden, D-01314 Dresden, Germany. Radboud Univ Nijmegen, Inst Mol & Mat, High Field Magnet Lab, NL-6525 ED Nijmegen, Netherlands. Iowa State Univ, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. RP Bergk, B (reprint author), Tech Univ Dresden, Inst Festkorperphys, D-01062 Dresden, Germany. EM b.bergk@fzd.de RI Canfield, Paul/H-2698-2014; Bianchi, Andrea/E-9779-2010 OI Bianchi, Andrea/0000-0001-9340-6971 NR 7 TC 9 Z9 9 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 630 EP 631 DI 10.1016/j.physc.2007.04.198 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500225 ER PT J AU Hagel, J Ignatchik, O Wosnitza, J Pfleiderer, C Schlueter, JA Davis, H Winter, R Gard, GL AF Hagel, J. Ignatchik, O. Wosnitza, J. Pfleiderer, C. Schlueter, J. A. Davis, H. Winter, R. Gard, G. L. TI Pressure dependence of the electronic properties of the quasi-two-dimensional organic superconductor beta ''-(ET)(2)SF5CH2CF2SO3 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE organic superconductors; Shubnikov-de Haas effect; electronic-transport properties AB We report on pressure-dependent superconducting and transport properties of the quasi-two-dimensional organic superconductor beta ''-(ET)(2)SF5CH2CF2SO3. With increasing pressure both the superconducting transition temperature, T-c, as well as the effective mass, m(c), decrease monotonously. By assuming a direct relationship between m(c) and the superconducting coupling parameter lambda, the pressure dependence of T-c can be well described by the modified McMillan equation. For all pressures in the metallic state the resistance follows p = p(0) + AT(2) at low temperatures. The coefficient A, however, is found to be not proportional to m(c)(2) as expected for a purely electronic origin of the T-2 behavior. (C) 2007 Elsevier B.V. All rights reserved. C1 Forschungszentrum Rossendorf EV, Hochfeld Magnetlab, D-01314 Dresden, Germany. Tech Univ Dresden, Inst Festkorperphys, D-01062 Dresden, Germany. Tech Univ Munich, Dept Phys, D-85748 Garching, Germany. Argonne Natl Lab, Mat Sci Div, Argonne, IL 60439 USA. Portland State Univ, Dept Chem, Portland, OR 97207 USA. RP Wosnitza, J (reprint author), Forschungszentrum Rossendorf EV, Hochfeld Magnetlab, D-01314 Dresden, Germany. EM j.wosnitza@fzd.de RI Pfleiderer, Christian/P-3575-2014 NR 6 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 639 EP 640 DI 10.1016/j.physc.2007.04.163 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500229 ER PT J AU Donath, JG Gegenwart, P Steglich, F Bauer, ED Sarrao, JL AF Donath, J. G. Gegenwart, P. Steglich, F. Bauer, E. D. Sarrao, J. L. TI Pressure effect on antiferromagnetism in CeRhIn5-xSnx studied by thermal expansion SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE CeRhIn5; heavy fermion system; quantum critical point; antiferromagnetism ID SUPERCONDUCTIVITY AB We present low-temperature thermal expansion measurements on the Sn-substituted heavy fermion antiferromagnet CeRhIn5-xSnx for 0 <= x <= 0.36 in which T-N(x) is linearly suppressed from 3.8 K at x = 0 to zero at x(c) approximate to 0.4. The application of the Ehrenfest relation allows to calculate the initial uniaxial and hydrostatic pressure dependences dT(N)/dP at various x. The observed non-linear variation with x is interpreted in terms of the Doniach diagram by an increase of the 4f-conduction electron hybridization induced by Sn-doping. As no traces of superconductivity are observed close to x(c), this system is ideally suited for the study of the magnetic quantum critical point. (C) 2007 Elsevier B.V. All rights reserved. C1 Max Planck Inst Chem Phys Solids, D-01187 Dresden, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Donath, JG (reprint author), Max Planck Inst Chem Phys Solids, D-01187 Dresden, Germany. EM donath@cpfs.mpg.de RI Bauer, Eric/D-7212-2011; Gegenwart, Philipp/A-7291-2017 NR 6 TC 4 Z9 4 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 661 EP 662 DI 10.1016/j.physc.2007.03.030 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500240 ER PT J AU Koitzsch, A Borisenko, S Inosov, D Geck, J Zabolotnyy, VB Shiozawa, H Knupfer, M Fink, J Buchner, B Bauer, ED Sarrao, JL Follath, R AF Koitzsch, A. Borisenko, Sn. Inosov, D. Geck, J. Zabolotnyy, V. B. Shiozawa, H. Knupfer, M. Fink, J. Buechner, B. Bauer, E. D. Sarrao, J. L. Follath, R. TI Observing the heavy fermions in CeCoIn5 by angle-resolved photoemission SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE heavy fermions; electronic structure; ARPES ID LATTICE AB We have investigated the low-energy electronic structure of the heavy fermion superconductor CeCoIn5 by angle-resolved photoemission. In particular, we study the role of the 4f electrons by Ce 4d-4f resonant photoemission spectroscopy. We observe a k-dependent hybridization and report on the temperature dependence of the f-states. (C) 2007 Elsevier B.V. All rights reserved. C1 IFW Dresden, D-01171 Dresden, Germany. TU Dresden, Inst Solid State Phys, D-01062 Dresden, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. BESSY, D-12489 Berlin, Germany. RP Koitzsch, A (reprint author), IFW Dresden, PO Box 270116, D-01171 Dresden, Germany. EM a.koitzsch@ifw-dresden.de RI Inosov, Dmytro/B-6781-2008; Bauer, Eric/D-7212-2011; Borisenko, Sergey/G-6743-2012; Fink, Joerg/A-6003-2012; Buchner, Bernd/E-2437-2016; Shiozawa, Hidetsugu/A-5206-2017; OI Borisenko, Sergey/0000-0002-5046-4829; Buchner, Bernd/0000-0002-3886-2680; Shiozawa, Hidetsugu/0000-0003-0603-2508; Bauer, Eric/0000-0003-0017-1937 NR 13 TC 2 Z9 2 U1 4 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 666 EP 667 DI 10.1016/j.physc.2007.03.290 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500242 ER PT J AU Ferreira, LM Bittar, EM Pagliuso, PG Hering, EN Ramos, SM Borges, HA Baggio-Saitovich, E Bauer, ED Thompson, JD Sarrao, JL AF Ferreira, L. Mendonca Bittar, E. M. Pagliuso, P. G. Hering, E. N. Ramos, S. M. Borges, H. A. Baggio-Saitovich, E. Bauer, E. D. Thompson, J. D. Sarrao, J. L. TI Pressure-temperature phase diagrams of in-plane doped CeRhIn5 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE heavy-fermion superconductors; antiferromagnetism; dilution; pressure-temperature phase diagrams AB In this work, we report a combined study about the effects of pressure and in-plane doping on the low temperature properties of AFM CeRhIn5. We have explored two different kinds of in-plane doping to perturb the AFM state of CeRhIn5. The La-doping in the Ce-site, which suppresses the AFM order simply by dilution and the Sn-doping in the In-sites, that suppresses the AFM order by increasing the Kondo-coupling. Electrical resistivity measurements under pressure were performed and the extracted pressure-temperature diagrams for these in-plane perturbed CcRhIn(5) single crystals are compared to the properties of the pure compound. (C) 2007 Elsevier B.V. All rights reserved. C1 Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. Pontificia Univ Catolica Rio de Janeiro, Dept Fis, BR-22453900 Rio De Janeiro, Brazil. Ctr Brasileiro Pesquisas Fis, BR-22290180 Rio De Janeiro, Brazil. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ferreira, LM (reprint author), Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. EM leticiem@ifi.unicamp.br RI Bauer, Eric/D-7212-2011; Ferreira, Leticie/C-4311-2012; Pagliuso, Pascoal/C-9169-2012; Bittar, Eduardo/B-6266-2008; Inst. of Physics, Gleb Wataghin/A-9780-2017; OI Bittar, Eduardo/0000-0002-2762-1312; Bauer, Eric/0000-0003-0017-1937 NR 7 TC 1 Z9 1 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 672 EP 673 DI 10.1016/j.physc.2007.03.077 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500245 ER PT J AU Ferreira, LM Pagliuso, PG Urbano, RR Gratens, X Oliveira, NF Movshovich, R Sarrao, JL Thompson, JD AF Ferreira, L. Mendonca Pagliuso, P. G. Urbano, R. R. Gratens, X. Oliveira, N. F., Jr. Movshovich, R. Sarrao, J. L. Thompson, J. D. TI High field phase diagram of CeCoIn5: A magnetization study SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE heavy-fermion superconduct; vortices dynamics; magnetization at high field AB We have performed magnetization and magnetic relaxation measurements on high-quality single crystals of CeCoIn5 at temperatures down to 28 mK and fields up to 17 T. The experiments were carried out by means of a force magnetometer operating in a plastic dilution refrigerator in a 18 T magnet. Data were collected with magnetic field applied both parallel and perpendicular to the ab-plane. For both orientations, pure magnetization signal reveals subtle changes in behavior in a very narrow field range near H-c2. The possible formation of the FFLO state in CeCoIn5 and how the vortices' dynamics evolve when crossing such state is discussed on the basis of our results. (C) 2007 Elsevier B.V. All rights reserved. C1 Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo, Brazil. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ferreira, LM (reprint author), Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. EM leticiem@ifi.unicamp.br RI Ferreira, Lydia/B-7511-2012; Ferreira, Leticie/C-4311-2012; Urbano, Ricardo/F-5017-2012; Inst. of Physics, Gleb Wataghin/A-9780-2017; Pagliuso, Pascoal/C-9169-2012 NR 7 TC 1 Z9 1 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 674 EP 675 DI 10.1016/j.physc.2007.03.079 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500246 ER PT J AU Onose, Y Ong, NP Petrovic, C AF Onose, Y. Ong, N. P. Petrovic, C. TI Thermal Hall conductivity and long-lived quasiparticles in CeCoIn5 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE quasiparticles; heavy fermion; thermal Hall effect ID SUPERCONDUCTIVITY; ENHANCEMENT AB In CeCoIn5, the thermal conductivity kappa(xx) and Hall conductivity kappa(xy) below T-c display large anomalies below T-c. The strong suppression of the anomalies in weak fields implies the existence of long-lived quasiparticles. We also discuss briefly the Wiedemann-Franz ratio and the existence of a strongly field-dependent spin-fluctuation heat current. (C) 2007 Elsevier B.V. All rights reserved. C1 Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Dept Phys, Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ong, NP (reprint author), Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. EM npo@prineeton.edu RI Petrovic, Cedomir/A-8789-2009; Onose, Yoshinori/F-1977-2010 OI Petrovic, Cedomir/0000-0001-6063-1881; NR 8 TC 0 Z9 0 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 676 EP 677 DI 10.1016/j.physc.2007.03.080 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500247 ER PT J AU Silhanek, AV Jaime, M Harrison, N Batista, CD Amitsuka, H Nakatsuji, S Balicas, L Kim, KH Mydosh, JA AF Silhanek, A. V. Jaime, M. Harrison, N. Batista, C. D. Amitsuka, H. Nakatsuji, S. Balicas, L. Kim, K. H. Mydosh, J. A. TI Field induced metastabilities in U(Ru0.96Rh0.04)(2)Si-2 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY AB U(Ru0.96Rh0.04)(2)Si-2 is an anisotropic itinerant 5f heavy electron system which exhibits a single field induced magnetic phase concealing a quantum critical point. We show that the boundary of this phase corresponds to a first order transition as revealed by (1) a large and symmetric specific heat anomaly, (2) an asymmetric magnetocaloric effect on entering and exiting this phase, and (3) a clear history and time-dependent specific heat. We explore the thermodynamic similarities with the mixed valence compound YbInCu4 and show that the out-of-equilibrium properties are analogous to those depicted by the critical state model for hard superconductors. (C) 2007 Elsevier B.V. All rights reserved. C1 Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Hokkaido Univ, Grad Sch Sci, Sapporo, Hokkaido 0600810, Japan. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Max Planck Inst Chem Phys Stoffe, D-01187 Dresden, Germany. RP Silhanek, AV (reprint author), Los Alamos Natl Lab, Natl High Magnet Field Lab, POB 1663,MS E536, Los Alamos, NM 87545 USA. EM alejandro.silhanek@fys.kuleuven.be RI Balicas, Luis/A-3110-2008; Amitsuka, Hiroshi/K-8539-2012; Jaime, Marcelo/F-3791-2015; Batista, Cristian/J-8008-2016 OI Jaime, Marcelo/0000-0001-5360-5220; NR 3 TC 0 Z9 0 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 682 EP 683 DI 10.1016/j.physc.2007.03.343 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500250 ER PT J AU Diener, P Rodiere, P Fletcher, JD Carrington, A Brison, JP Prozorov, R Olheiser, T Giannetta, RW AF Diener, P. Rodiere, P. Fletcher, J. D. Carrington, A. Brison, J. P. Prozorov, R. Olheiser, T. Giannetta, R. W. TI Anisotropic superconductivity in NbSe2 probed by magnetic penetration depth SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE NbSe2; penetration depth; superfluid density ID 2H-NBSE2 AB NbSe2 shows coexistence of a charge density wave (TCDW similar to 32 K) with a superconducting state below T = 7.2 K. Recent ARPES measurements revealed different values of the superconducting gap on the main sheets of the Fermi surface. These results suggest a multigap superconductivity such as in MgB2. The temperature dependence of the magnetic penetration depth (;.(T)) down to T,11 6 has been measured on high quality single crystals in the Meissner state. A strong increase of the in-plane penetration depth is observed, signaling the presence of low lying excitations. Given the relative contributions of each Fermi surface sheet, these measurements indicate that a reduced gap is not necessarily only found on the small Se sheet as suggested by the ARPES measurements. These results are discussed in a framework of multigap superconductivity. (C) 2007 Elsevier B.V. All rights reserved. C1 Univ Grenoble 1, Inst Neel, CNRS, F-38042 Grenoble, France. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Iowa State Univ, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. RP Diener, P (reprint author), Univ Grenoble 1, Inst Neel, CNRS, F-38042 Grenoble, France. EM pierre.rodiere@grenoble.cnrs.fr RI Prozorov, Ruslan/A-2487-2008; Fletcher, Jonathan/J-9023-2012 OI Prozorov, Ruslan/0000-0002-8088-6096; Fletcher, Jonathan/0000-0002-2386-9361 NR 5 TC 1 Z9 1 U1 2 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 700 EP 701 DI 10.1016/j.physc.2007.03.145 PN 1 PG 2 WC Physics, Applied SC Physics GA 216IA UT WOS:000249870500258 ER PT J AU Comes, R Izquierdo, M Megtert, S Albouy, PA Avila, J Valbuena, MA Gu, G Abell, JS Asensio, MC AF Comes, R. Izquierdo, M. Megtert, S. Albouy, P. A. Avila, J. Valbuena, M. A. Gu, G. Abell, J. S. Asensio, M. C. TI X-ray diffuse scattering experiments on bismuth based high T-c superconductors SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE diffuse scattering; Bi-based superconductors AB A detailed X-ray diffuse scattering study of the recently found two dimensional (2D) displacive short range order (SRO) superstructure, with doubled periodicity along the orthorhombic a direction from the high T, superconductors Bi2Sr2CaCu2O8+delta (BISCO-2212) is reported. The investigation has been extended to high and low temperatures for optimally doped crystals, to crystals with different doping levels and to the one layer compound Bi2Sr2Cu6+delta (BISCO-2201). The most striking feature is that both, the intensity of the diffuse scattering and the extent of the 2DSRO vary with doping as the critical temperature, T, These findings show that these short range ordering features are of importance for a better understanding of high T-c materials, at least those from the BISCO family. (c) 2007 Published by Elsevier B.V. C1 Ctr Univ Paris Sud, Synchrotron LURE, F-91898 Orsay, France. Synchrotron SOLEIL, F-91192 Gif Sur Yvette, France. Ctr Univ Paris Sud, Phys Solides Lab, F-91405 Orsay, France. Brookhaven Natl Lab, Dept Phys, Upton, NY 11975 USA. Univ Birmingham, Sch Met & Mat Sci, Birmingham B15 2TT, W Midlands, England. RP Comes, R (reprint author), Ctr Univ Paris Sud, Synchrotron LURE, Bat 209 D, F-91898 Orsay, France. EM Trebor.semoc@u-psud.fr NR 4 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 730 EP 731 DI 10.1016/j.physc.2007.03.154 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600007 ER PT J AU Chen, DX Bartolome, E Pardo, E Sanchez, A Bozzo, B Granados, X Puig, T Obradors, X Claus, H AF Chen, D.-X. Bartolome, E. Pardo, E. Sanchez, A. Bozzo, B. Granados, X. Puig, T. Obradors, X. Claus, H. TI AC susceptibility of half-half jointed melt-textured YBCO rings SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY ID COATED CONDUCTORS; YBA2CU3O7-DELTA AB Three half-half jointed melt-textured YBCO rings have been prepared and their ac susceptibility X has been measured at 77 K as a function of field amplitude H and frequency f. All the half rings have their c-axis along the ring axis and there is a nonzero a(b)-axis misalignment angle phi between the two jointed halves. It is found that chi(H-m) is consistent with the critical-state model for rings with 0 degrees and 8 degrees, whereas chi(H-m,f) is anomalous for the ring with phi = 14 degrees. (c) 2007 Elsevier B.V. All rights reserved. C1 UAB, Dept Fis, ICREA, Bellaterra 08193, Spain. UAB, Dept Fis, Grp Electromagnetisme, Bellaterra 08193, Spain. CSIC, Inst Ciencia Mat Barcelona, Bellaterra 08193, Spain. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Chen, DX (reprint author), UAB, Dept Fis, ICREA, Bellaterra 08193, Spain. EM chen@maxwell.uab.es RI Sanchez, Alvaro/C-7041-2008; Obradors, Xavier/A-8146-2012; Puig, Teresa/O-1077-2013; OI Puig, Teresa/0000-0002-1873-0488; Sanchez, Alvaro/0000-0002-2988-0289; Pardo, Enric/0000-0002-6375-4227 NR 10 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 770 EP 771 DI 10.1016/j.physc.2007.03.118 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600025 ER PT J AU Rydh, A Xie, R Zach, M Welp, U Kwok, WK Crabtree, GW Bending, S Milosevic, MV Peeters, FM AF Rydh, A. Xie, R. Zach, M. Welp, U. Kwok, W. K. Crabtree, G. W. Bending, S. Milosevic, M. V. Peeters, F. M. TI Magnetization of a few-fluxoid lead crystal SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE hall micro-probe; mesoscopic superconductivity; lead; single crystal; fluxoid quantization ID SUPERCONDUCTORS AB We experimentally study a triangular, micrometer-sized Pb single crystal through ballistic Hall micro-probe magnetometry. This mesoscopic system allows an easy adjustment of the maximum accomodated fluxoid state by tuning the temperature. Magnetization loops of the type-I superconductor were measured at various temperatures up to T-c = 7.18 K. We observe several novel features, including mestastable fluxoid states and changes in the normal-to-superconducting transition mechanism with temperature. (c) 2007 Elsevier B.V. All rights reserved. C1 Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Univ Bath, Dept Phys, Bath BA2 7AY, Avon, England. Univ Antwerp, Dept Fys, B-2020 Antwerp, Belgium. RP Rydh, A (reprint author), Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden. EM arydh@physto.se RI Zach, Michael/D-4160-2009; Milosevic, Milorad/H-9393-2012; Rydh, Andreas/A-7068-2012; CMT, UAntwerpen Group/A-5523-2016 OI Zach, Michael/0000-0002-4409-3419; Xie, Ruobing/0000-0003-0266-9122; Rydh, Andreas/0000-0001-6641-4861; NR 12 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 793 EP 794 DI 10.1016/j.physc.2007.04.042 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600036 ER PT J AU Born, D Stornaiuolo, D Tafuri, F Kirtley, JR Kogan, VG Medaglia, PG Orgiani, P Balestrino, G Bauch, T Lombardi, F AF Born, D. Stornaiuolo, D. Tafuri, F. Kirtley, J. R. Kogan, V. G. Medaglia, P. G. Orgiani, P. Balestrino, G. Bauch, T. Lombardi, F. TI Transport measurements on ultra-thin CaBaCuO films SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE thin film; HTS; Perl vortex dynamics; vortex quantum tunnelling ID PEARL VORTICES; DISSIPATION; SYSTEMS AB We investigated transport properties of ultra-thin CaBaCuO (CBCO) films, focusing on vortex dynamics. By measuring current-voltage characteristics we found evidence that at high temperatures the vortices are thermally activated at the edges of the bridge and pushed in, causing dissipation and power-law dependence of the voltage from the current. At lower temperatures, the experimental curves change shape. We compared these data with the predicted behaviour for vortex quantum tunnelling and found a very good agreement. Measurements performed at ultra-low temperatures (down to 60 mK) in a particular low noise environment provide additional evidence of the robustness of the observed effects. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Naples Federico 2, INFM, CNR, I-80126 Naples, Italy. Seconda Univ Naples, SUN, I-80125 Naples, Italy. IBM Corp, Thomas J Watson Res Ctr, Yorktown Hts, NY 10598 USA. US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Univ Roma Tor Vergata, INFM, CNR, Rome, Italy. Chalmers, Dept Microtechnol & Nanosci, Quantum Device Phys Lab, S-41296 Gothenburg, Sweden. RP Born, D (reprint author), Univ Naples Federico 2, INFM, CNR, I-80126 Naples, Italy. EM mail@d-born.de RI Orgiani, Pasquale/E-7146-2013; Bauch, Thilo/B-5756-2016; OI Orgiani, Pasquale/0000-0002-1082-9651; Bauch, Thilo/0000-0002-8918-4293; Tafuri, Francesco/0000-0003-0784-1454 NR 8 TC 0 Z9 0 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 845 EP 846 DI 10.1016/j.physc.2007.04.140 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600062 ER PT J AU Yoshida, T Zhou, XJ Hussain, Z Shen, ZX Fujimori, A Komiya, S Ando, Y Eisaki, H Uchinda, S AF Yoshida, T. Zhou, X. J. Hussain, Z. Shen, Z. X. Fujimori, A. Komiya, Seiki Ando, Yolchi Eisaki, H. Uchinda, S. TI Effects of Zn-impurity scattering in La2-xSrxCuO4 studied by angle-resolved photoemission spectroscopy SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE cuprates; impurity effect; ARPES ID HIGH-TEMPERATURE SUPERCONDUCTORS AB We have performed angle-resolved photoemission measurements on Zn-doped La2-xSrxCuO4 in order to investigate the effects of Zn impurities on the quasi-particle (QP) structure. The widths of the momentum distribution curves (MDCs) showed an energy-independent increased by the Zn substitution in the low energy scale (similar to 70 meV). The observed strong broadening of the MDC width was generally consistent with the dramatic increase of the residual resistivity by the Zn impurities. (c) 2007 Elsevier B.V. All rights reserved. C1 Univ Tokyo, Dept Complex Sci & Engn, Chiba 2778561, Japan. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Cent Res Inst Elect Power Ind, Tokyo 2018511, Japan. Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki 3058568, Japan. Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. RP Yoshida, T (reprint author), Univ Tokyo, Dept Complex Sci & Engn, Chiba 2778561, Japan. EM teppei@k.u-tokyo.ac.jp RI Ando, Yoichi/B-8163-2013 OI Ando, Yoichi/0000-0002-3553-3355 NR 7 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 872 EP 873 DI 10.1016/j.physc.2007.03.095 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600074 ER PT J AU Izquierdo, M Avila, J Roca, L Gu, G Li, ZZ Raffy, H Asensio, MC AF Izquierdo, M. Avila, J. Roca, Lydia Gu, G. Li, Z. Z. Raffy, Helene Asensio, M. C. TI Understanding the origin of the shadow bands of Bi-based superconductors with angle resolved photoemission SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE shadow bands; bi-based superconductors AB Angle resolved photoemission spectroscopy (ARPES) has been used to investigate the shadow bands (SB) present at the Fermi surface (FS) of bismuth based superconductors. Bi2Sr2CaCu2O8+delta (Bi-2212) single crystals and BiSr2CaCu2O8+delta (Bi-2201) thin films have been studied by momentum distribution curves (MDCs) along the Gamma Y high symmetry direction in two different Brillouin zones (BZ). The results show the ratio shadow bands/main band (SB/MB) to be constant as a function of both the doping level and the number of CuO2 planes, which discards the antiferromagnetic (AF) scenario to explain their origin. On the other hand, the SB and the main bands (MB) have different initial state symmetry, which implies that the orthorhombicity exhibited by these materials cannot be responsible for their emergence at the FS. An interpretation on the basis of a c(2 x 2) surface reconstruction, recently observed by LEED, becomes be only plausible explanation compatible with all experimental data. (c) 2007 Elsevier B.V. All rights reserved. C1 Ctr Univ Paris Sud, Synchroton LURE, F-91898 Orsay, France. L Orme Merisiers, Synchrotron SOLEIL, F-91192 Gif Sur Yvette, France. Dept Phys, Brookhaven Natl Lab, Upton, NY 11975 USA. Ctr Univ Paris Sud, Phys Solides Lab, F-91405 Orsay, France. RP Izquierdo, M (reprint author), Ctr Univ Paris Sud, Synchroton LURE, Bat 209 D, F-91898 Orsay, France. EM manuel.izquierdo@synchrotron-soleil.fr NR 3 TC 0 Z9 0 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 937 EP 938 DI 10.1016/j.physc.2007.03.309 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600103 ER PT J AU Lindroos, M Arpiainen, V Sahrakorpi, S Markiewicz, RS Zhou, XJ Yoshida, T Yang, WL Kakeshita, T Eisaki, H Uchida, S Fujimori, A Hussain, Z Shen, ZX Bansil, A AF Lindroos, M. Arpiainen, V. Sahrakorpi, S. Markiewicz, R. S. Zhou, X. J. Yoshida, T. Yang, W. L. Kakeshita, T. Eisaki, H. Uchida, S. Fujimori, A. Hussain, Z. Shen, Z.-X. Bansil, A. TI Existence of a quasiparticle remnant in angle-resolved photoemission spectrum of La2-xSrxCuO4 SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE La2-xSrxCuO4; electronic structure; fermi surface; ARPES ID CUPRATE SUPERCONDUCTORS AB We compare first-principles angle-resolved photoemission (ARPES) computations with the corresponding measurements from an underdoped single crystal of La2-xSrxCuO4 (LSCO) using an experimental geometry different from that employed in earlier work [S. Sahrakorpi et al., Phys. Rev. Lett. 95 (2005) 157601, T. Yoshida et al., Phys. Rev. B 74 (2006) 224510]. A high level of accord is found between theory and experiment extending over the first and higher Brillouin zones (BZs), further supporting the notion that a quasiparticle remnant persists in LSCO despite the presence of strong correlation effects in the system. (c) 2007 Elsevier B.V. All rights reserved. C1 Tampere Univ Technol, Inst Phys, FIN-33101 Tampere, Finland. Northeastern Univ, Dept Phys, Boston, MA 02115 USA. Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA. Stanford Univ, Dept Appl Phys, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Univ Tokyo, Dept Complex Sci & Engn, Chiba 277, Japan. ISTEC, Superconduct Res Lab, Tokyo 135, Japan. Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki 305, Japan. Univ Tokyo, Dept Phys, Tokyo 113, Japan. RP Lindroos, M (reprint author), Tampere Univ Technol, Inst Phys, PO Box 692, FIN-33101 Tampere, Finland. EM matti.lindroos@tut.fi RI Yang, Wanli/D-7183-2011 OI Yang, Wanli/0000-0003-0666-8063 NR 4 TC 0 Z9 0 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 941 EP 942 DI 10.1016/j.physc.2007.03.358 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600105 ER PT J AU Ozyuzer, L Ozdemir, M Kurter, C Hinks, DG Gray, KE AF Ozyuzer, L. Ozdemir, M. Kurter, C. Hinks, D. G. Gray, K. E. TI Effect of magnetic field on quasiparticle branches of intrinsic Josephson junctions with ferromagnetic layer SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE intrinsic josephson junctions; spin-polarized current; Tunneling spectroscopy ID SINGLE-CRYSTALS AB The interlayer tunneling spectroscopy has been performed on micron-sized mesa arrays of HgBr2 intercalated superconducting Bi2212 single crystals. A ferromagnetic multilayer (Au/Co/Au) is deposited on top of the mesas. The spin-polarized current is driven along the c-axis of the mesas through a ferromagnetic Co layer and the hysteretic quasiparticle branches are observed at 4.2 K. Magnetic field evolution of hysteretic quasiparticle branches is obtained to examine the effect of injected spin-polarized current on intrinsic Josephson junction characteristics. It is observed that there is a gradual distribution in quasiparticle branches with the application of magnetic field and increasing field reduces the switching current progressively. (c) 2007 Elsevier B.V. All rights reserved. C1 Inst Technol, Dept Phys, TR-35430 Izmir, Turkey. Div Mat Sci, Argonne Natl Lab, Argonne, IL 60439 USA. RP Ozyuzer, L (reprint author), Inst Technol, Dept Phys, TR-35430 Izmir, Turkey. EM ozyuzer@iyte.edu.tr RI Ozyuzer, Lutfi/H-3142-2011 NR 4 TC 1 Z9 1 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 950 EP 951 DI 10.1016/j.physc.2007.03.322 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600109 ER PT J AU Iavarone, M Karapetrov, G Fedor, J Rosenman, D Kwok, WK AF Iavarone, Maria Karapetrov, Goran Fedor, Jan Rosenman, Daniel Kwok, Wai-Kwong TI Vortex lattice transitions in artificially engineered NbSe2 single crystals observed by STM SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE superconductivity; STM; abrikosov vortices AB The direct imaging of vortices in heterostructures superconductor/normal metal on a sub-micron scale highlights a new breakthrough in exploring confinement effects in vortex dynamics. Using scanning tunneling microscopy and spectroscopy, we mapped the distribution of local density of states in a single crystal patterned with an array of sub-micron normal metal centers. The magnetic flux structure undergoes a series of phase transitions between different configurations. The patterning of the sample shows to have an important role on the system dynamics, producing vortex-chain states. Understanding and control of vortex dynamics in these systems could serve as a model to get better insight in the pinning mechanisms. (c) 2007 Elsevier B.V. All rights reserved. C1 Div Mat Sci, Argonne Natl Lab, Argonne, IL 60439 USA. RP Iavarone, M (reprint author), Div Mat Sci, Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM maria@anl.gov RI Iavarone, Maria/C-3628-2008; Karapetrov, Goran/C-2840-2008 OI Karapetrov, Goran/0000-0003-1113-0137 NR 5 TC 0 Z9 0 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 952 EP 953 DI 10.1016/j.physc.2007.03.323 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600110 ER PT J AU Kurter, C Mazur, D Ozyuzer, L Hinks, DG Gray, KE AF Kurter, C. Mazur, D. Ozyuzer, L. Hinks, D. G. Gray, K. E. TI Investigation of the tunneling spectra in HgBr2-intercalated Bi-2212 single crystals below and above T-c SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE high temperature superconductors; intrinsic Josephson junctions; tunneling spectroscopy; pseudogap ID PSEUDOGAP; BI2SR2CACU2O8+DELTA; FEATURES AB Interlayer tunneling spectroscopy measurements were performed on mesa arrays of Bi-2212 single crystals, intercalated with HgBr2, Tunneling conductances were obtained over a wide temperature range to examine the spectral features, especially the behavior of the quasiparticle peaks corresponding to superconducting energy gaps (SGs). Experimental spectra showed that gap-like features are still present even for the temperatures far above the transition temperature, T-c. This evidence is consistent with the idea that the SG evolves into a pseudogap above T-c for HgBr2-intercalated Bi-2212 single crystals. Published by Elsevier B.V. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Izmir Inst Technol, Dept Phys, TR-35430 Izmir, Turkey. RP Kurter, C (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM kurter@anl.gov RI Ozyuzer, Lutfi/H-3142-2011; Mazur, Daniel/B-8303-2014 OI Mazur, Daniel/0000-0003-2524-5226 NR 6 TC 0 Z9 0 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 1090 EP 1091 DI 10.1016/j.physc.2007.03.222 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600175 ER PT J AU Reichhardt, C Reichhardt, CJO Bishop, AR AF Reichhardt, C. Reichhardt, C. J. Olson Bishop, A. R. TI Commensurate and incommensurate checkerboard charge ordered states SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY ID TRANSITION-METAL OXIDES; LONG-RANGE INTERACTIONS AB We consider a system of charged particles interacting through Coulomb repulsion with an additional short range attraction to model charge ordering in cuprate superconductors. The particles move over a background periodic substrate. In the absence of the substrate, we find a checkerboard type ordering of the charges along with a variety of other crystalline states as the charge density is varied. In the presence of a substrate, there are additional commensurate-incommensurate grain boundary structures that form within the checkerboard state. We compare our results to recent scanning tunneling experiments. (c) 2007 Elsevier B.V. All rights reserved. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Reichhardt, C (reprint author), Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. EM charlesr@cnls.lanl.gov NR 4 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 1178 EP 1179 DI 10.1016/j.physc.2007.03.419 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600217 ER PT J AU Bel, G Li, DP Rosenstein, B Vinokur, V Zhuravlev, V AF Bel, G. Li, D. P. Rosenstein, B. Vinokur, V. Zhuravlev, V. TI Dynamics of disordered type-II superconductors: Peak effect and the I-V curves SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY DE type-II superconductor; glass transition; quenched disorder AB We quantitatively describe the competition between the thermal fluctuations and disorder by the Ginzburg-Landau approach using both the replica method in statics and the dynamical Martin-Siggia-Rose approach which allows generalization beyond linear response. The two methods are consistent in static, while the dynamical method allows calculation of the critical current as function of magnetic field and temperature. The surface in the J-B-T space defined by this function separates between a dissipative moving vortex matter regime and vortex glass. The non-Ohmic I-V curve is obtained. (c) 2007 Elsevier B.V. All rights reserved. C1 Natl Chiao Tung Univ, Dept Electrophys, Hsinchu 30050, Taiwan. Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA. Beijing Univ, Sch Phys, Beijing 100871, Peoples R China. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Rosenstein, B (reprint author), Natl Chiao Tung Univ, Dept Electrophys, Hsinchu 30050, Taiwan. EM vortexbar@yahoo.com RI Bel, Golan/C-6528-2008; BEL, GOLAN/F-1573-2012 OI Bel, Golan/0000-0002-3307-9478; BEL, GOLAN/0000-0002-3307-9478 NR 9 TC 2 Z9 2 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 1213 EP 1214 DI 10.1016/j.physc.2007.04.169 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600234 ER PT J AU Reichhardt, CJO Reichhardt, C AF Reichhardt, C. J. Olson Reichhardt, C. TI Probing vortex systems with individual vortex manipulation SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors CY JUL 09-14, 2006 CL Dresden, GERMANY AB We show that by manipulating individual vortices or small groups of vortices in a superconductor, such as with a magnetic force microscope tip, a number of interesting properties of the system can be extracted. For example, it should be possible to test directly whether vortices can entangle, to measure the properties of the vortex line tension across melting and disordering transitions, probe correlation behavior near depinning, and characterize the pinning landscape. (c) 2007 Elsevier B.V. All rights reserved. C1 Los Alamos Natl Lab, Ctr Nonlinear Studies, Div Theoret, Los Alamos, NM 87545 USA. RP Reichhardt, CJO (reprint author), Los Alamos Natl Lab, Ctr Nonlinear Studies, Div Theoret, Los Alamos, NM 87545 USA. EM cjrx@lanl.gov NR 4 TC 0 Z9 0 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD SEP 1 PY 2007 VL 460 BP 1284 EP 1285 DI 10.1016/j.physc.2007.03.315 PN 2 PG 2 WC Physics, Applied SC Physics GA 216IB UT WOS:000249870600268 ER PT J AU Villarreal, P De Lara-Castells, MP Prosmiti, R Delgado-Barrio, G Lopez-Duran, D Gianturco, FA Jellinek, J AF Villarreal, P. De lara-Castells, M. P. Prosmiti, R. Delgado-Barrio, G. Lopez-Duran, D. Gianturco, F. A. Jellinek, J. TI Spectral simulations of polar diatomic molecules immersed in He clusters: application to the ICl (X) molecule SO PHYSICA SCRIPTA LA English DT Article; Proceedings Paper CT 16th Biennial European Conference on Dynamics of Molecular (MOLEC) CY SEP, 2006 CL Levico, ITALY ID RESOLUTION INFRARED-SPECTRA; HELIUM CLUSTERS; VIBRATIONAL PREDISSOCIATION; SPECTROSCOPY; NANODROPLETS; DYNAMICS; DROPLETS; HF AB A recently developed quantum-chemistry-like methodology to study molecules solvated in atomic clusters is applied to the IC1 (iodine chloride) polar diatomic molecule immersed in clusters of He atoms. The atoms of the solvent clusters are treated as the `electrons' and the solvated molecule as a structured` nucleus' of the combined solvent-solute system. The helium-helium and helium-dopant interactions are represented by parametrized two-body and ab initio three-body potentials, respectively. The ground-state wavefunctions are used to compute the infrared (IR) spectra of the solvated molecule. In agreement with the experimental observations, the computed spectra exhibit considerable differences depending on whether the solvent cluster is comprised of bosonic (He-4) or fermionic (He-3) atoms. The source of these differences is attributed to the different spin-statistics of the solvent clusters. The bosonic versus fermionic nature of the solvent is reflected in the IR absorption selection rules. Only P and R branches with single state transitions appear in the spectrum when the molecule is solvated in a bosonic cluster. On the other hand, when the solvent represents a fermionic environment, quasi-degenerate multiplets of spin states contribute to each branch and, in addition, the Q-branch becomes also allowed. Combined, these two factors explain the more congested nature of the spectrum in the fermionic case. C1 CSIC, Inst Math & Phys Fundamental, E-28006 Madrid, Spain. Univ Rome, INFM, Dept Chem, I-00185 Rome, Italy. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Villarreal, P (reprint author), CSIC, Inst Math & Phys Fundamental, Serrano 123, E-28006 Madrid, Spain. EM p.villarreal@imaff.cfmac.csic RI de Lara-Castells, Maria Pilar/C-5846-2014; Villarreal, Pablo/K-2397-2014 OI de Lara-Castells, Maria Pilar/0000-0001-8697-5770; NR 44 TC 13 Z9 13 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-8949 J9 PHYS SCRIPTA JI Phys. Scr. PD SEP PY 2007 VL 76 IS 3 BP C96 EP C103 DI 10.1088/0031-8949/76/3/N15 PG 8 WC Physics, Multidisciplinary SC Physics GA 205FY UT WOS:000249100600025 ER PT J AU Michaelson, S Ternyak, O Akhvlediani, R Williams, OA Gruen, D Hoffman, A AF Michaelson, Sh. Ternyak, O. Akhvlediani, R. Williams, O. A. Gruen, D. Hoffman, A. TI Hydrogen concentration and bonding in nano-diamond films of varying grain sizes grown by different chemical vapor deposition methods SO PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT 12th Hasselt Diamond Workshop 2007 (SBDD XII) CY FEB 28-MAR 02, 2007 CL Hasselt Univ, Diepenbeek Hasselt, BELGIUM HO Hasselt Univ ID HYDROCARBON FILMS; AMORPHOUS-CARBON AB Hydrogen in a variety of forms (molecular hydrogen, atomic hydrogen, hydrocarbon radicals) is involved in diamond formation. The present work studies the incorporation of hydrogen and its bonding configuration in diamond films composed of diamond grains of varying size which were deposited by three different methods: hot filament (HF), micro wave (MW) and direct current glow discharge (dc GD) chemical vapor deposition (CVD). The size of diamond grains which constitute the films varies in the following way: hundreds of nm in the case of HF CVD (similar to 300 nm), tens nm in the case of MW CVD (3-30 nm) and a few nm in the case of dc GD CVD (similar to 5 nm). Raman spectroscopy, secondary ion mass spectroscopy (SIMS) and high resolution electron energy loss spectroscopy (HR-EELS) were applied to investigate the hydrogen trapping in the films. The retention of hydrogen in the films increases with decreasing grain size, indicating that most likely hydrogen is bonded and trapped in grain boundaries as well as on the films surfaces. Raman and HR-EELS analysis show that hydrogen is bonded to sp(2)- and sp(3)-hybridized carbon, giving rise to typical C-H vibration modes. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. C1 Technion Israel Inst Technol, Schulich Fac Chem, IL-32000 Haifa, Israel. Univ Hasselt, Inst Mat Res, B-3590 Diepenbeek, Belgium. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RP Hoffman, A (reprint author), Technion Israel Inst Technol, Schulich Fac Chem, IL-32000 Haifa, Israel. EM choffman@tx.technion.ac.il RI Williams, Oliver/B-2776-2009; OI Williams, Oliver/0000-0002-7210-3004 NR 24 TC 13 Z9 13 U1 1 U2 5 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 1862-6300 J9 PHYS STATUS SOLIDI A JI Phys. Status Solidi A-Appl. Mat. PD SEP PY 2007 VL 204 IS 9 BP 2860 EP 2867 DI 10.1002/pssa.200776302 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 213EJ UT WOS:000249648700005 ER PT J AU Achatz, P Garrido, JA Williams, OA Brun, P Gruen, DM Kromka, A Steinmuller, D Stutzmann, M AF Achatz, P. Garrido, J. A. Williams, O. A. Brun, P. Gruen, D. M. Kromka, A. Steinmueller, D. Stutzmann, M. TI Structural, optical, and electronic properties of nanocrystalline and ultrananocrystalline diamond thin films SO PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT 12th Hasselt Diamond Workshop 2007 (SBDD XII) CY FEB 28-MAR 02, 2007 CL Hasselt Univ, Diepenbeek-Hasselt, BELGIUM HO Hasselt Univ ID AMORPHOUS-CARBON; RAMAN-SPECTRA; GROWTH AB The structural, optical, and electronic properties of nanocrystalline diamond thin films grown from a hydrogen-rich CH4/H-2 gas phase via hot filament (HF) CVD and of ultrananocrystalline diamond thin films grown from an argon-rich sp(2) gas phase via microwave plasma enhanced (MPE) CVD have been studied. Depending on the growth conditions, these diamond films can have markedly different structural properties, as revealed by atomic force microscopy and Raman spectroscopy. Nevertheless, similarities in the electronic band structure can be seen from transport and optical measurements. In the case of nominally undoped films, both types of material show variable range hopping in localized states near the Fermi level in the whole temperaturerange from 300-650 K. Therefore, the overall density of states has to be the same for these two microstructures. Nitrogen incorporation in the ultrananocrystalline diamond films leads to changes in the optical absorption, which has been investigated using photothermal deflection and spectrally resolved photocurrent spectroscopy. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. C1 CNRS, Inst Neel, F-38042 Grenoble 09, France. CEA Grenoble, DRFMC, SPSMS, F-38054 Grenoble, France. Tech Univ Munich, Walter Schottky Inst, D-85748 Garching, Germany. Univ Hasselt, Inst Mat Res, B-3590 Diepenbeek, Belgium. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Hartstoffbeschichtungs GmbH, P BeSt Coating, A-6150 Steinach, Austria. RP Achatz, P (reprint author), CNRS, Inst Neel, BP 166, F-38042 Grenoble 09, France. EM philipp.achatz@grenoble.cnrs.fr RI Williams, Oliver/B-2776-2009; bruno, paola/G-5786-2011; Kromka, Alexander/G-9139-2014; Garrido, Jose A./K-7491-2015; Stutzmann, Martin/B-1480-2012; OI Kromka, Alexander/0000-0002-3531-6748; Garrido, Jose A./0000-0001-5621-1067; Williams, Oliver/0000-0002-7210-3004; Stutzmann, Martin/0000-0002-0068-3505 NR 27 TC 14 Z9 14 U1 1 U2 15 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0031-8965 J9 PHYS STATUS SOLIDI A JI Phys. Status Solidi A-Appl. Mat. PD SEP PY 2007 VL 204 IS 9 BP 2874 EP 2880 DI 10.1002/pssa.200776337 PG 7 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 213EJ UT WOS:000249648700007 ER PT J AU Berrah, N Bilodeau, RC Dumitriu, I Bozek, JD Gibson, ND Walter, CW Ackerman, GD Zatsarinny, O Gorczyca, TW AF Berrah, N. Bilodeau, R. C. Dumitriu, I. Bozek, J. D. Gibson, N. D. Walter, C. W. Ackerman, G. D. Zatsarinny, O. Gorczyca, T. W. TI Shape resonances in the absolute K-shell photodetachment of B- SO PHYSICAL REVIEW A LA English DT Article ID ATOMIC NEGATIVE-IONS; R-MATRIX CODES; ELECTRON-AFFINITY; POSTCOLLISION-INTERACTION; COLLISION-THEORY; HIGH-RESOLUTION; THRESHOLD; DETACHMENT; ENERGIES; DYNAMICS AB K-shell photodetachment of B- has been measured using the collinear photon-ion beamline at the Advanced Light Source, Lawrence Berkeley National Laboratory, as well as calculated using two separate R-matrix methods. The measurement of the absolute photodetachment cross section, as a function of photon energy, exhibits three near-threshold shape resonances due to the S-3, P-3, and D-3 final partial waves. A fit to the measured data using three resonance profiles shows good overall qualitative agreement with the three partial wave cross sections calculated using either R-matrix method. However, certain significant and unresolved quantitative discrepancies exist between the experimentally inferred and the calculated resonance profiles. C1 Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Denison Univ, Dept Phys & Astron, Granville, OH 43023 USA. RP Bilodeau, RC (reprint author), Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. EM rcbilodeau@lbl.gov RI Bozek, John/E-4689-2010; Bozek, John/E-9260-2010; OI Bozek, John/0000-0001-7486-7238; Bilodeau, Rene/0000-0001-8607-2328 NR 57 TC 12 Z9 12 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 2007 VL 76 IS 3 AR 032713 DI 10.1103/PhysRevA.76.032713 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 215CN UT WOS:000249786000095 ER PT J AU Hastings, MB AF Hastings, M. B. TI Random unitaries give quantum expanders SO PHYSICAL REVIEW A LA English DT Article ID GRAPHS AB We show that randomly choosing the matrices in a completely positive map from the unitary group gives a quantum expander. We consider Hermitian and non-Hermitian cases, and we provide asymptotically tight bounds in the Hermitian case on the typical value of the second largest eigenvalue. The key idea is the use of Schwinger-Dyson equations from lattice gauge theory to efficiently compute averages over the unitary group. C1 Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Hastings, MB (reprint author), Los Alamos Natl Lab, Ctr Nonlinear Studies, POB 1663, Los Alamos, NM 87545 USA. NR 20 TC 19 Z9 19 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 2007 VL 76 IS 3 AR 032315 DI 10.1103/PhysRevA.76.032315 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 215CN UT WOS:000249786000057 ER PT J AU Horner, DA Morales, F Rescigno, TN Martin, F McCurdy, CW AF Horner, D. A. Morales, F. Rescigno, T. N. Martin, F. McCurdy, C. W. TI Two-photon double ionization of helium above and below the threshold for sequential ionization SO PHYSICAL REVIEW A LA English DT Article ID ELECTRON CORRELATION; BREAKUP; HE AB We present accurate cross sections for two-photon double ionization of helium at photon energies above and below the threshold for sequential double ionization. Above this threshold (54.4 eV), sequential ionization competes with nonsequential ionization. Remarkably, even below 54.4 eV, sequential ionization leaves a clear signature in the magnitude and shape of both the total and energy-sharing cross sections-even though at these energies it is only a virtual process. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Autonoma Madrid, Dept Quim C9, E-28049 Madrid, Spain. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. RP Horner, DA (reprint author), Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. RI Martin, Fernando/C-3972-2014 OI Martin, Fernando/0000-0002-7529-925X NR 16 TC 90 Z9 91 U1 1 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 2007 VL 76 IS 3 AR 030701 DI 10.1103/PhysRevA.76.030701 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 215CN UT WOS:000249786000011 ER PT J AU Huang, XR Peng, RW Wang, Z Gao, F Jiang, SS AF Huang, X. R. Peng, R. W. Wang, Z. Gao, F. Jiang, S. S. TI Charge-oscillation-induced light transmission through subwavelength slits and holes SO PHYSICAL REVIEW A LA English DT Article ID SURFACE-PLASMONS; OPTICAL-TRANSMISSION; METALLIC GRATINGS; ARRAYS AB We present a concrete picture of spoof surface plasmons (SSPs) combined with cavity resonance to clarify the basic mechanism underlying extraordinary light transmission through metal films with subwavelength slits or holes. This picture may indicate a general mechanism of metallic nanostructure optics: When light is incident on a nonplanar conducting surface, the free electrons cannot move homogeneously in response to the incident electric field, i.e., their movement can be impeded at the rough parts, forming inhomogeneous charge distributions. The oscillating charges and dipoles then emit photons (similar to Thomson scattering of x rays by oscillating electrons), and the interference between the photons may give rise to anomalous transmission, reflection, or scattering. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Nanjing Univ, Natl Lab Solid State Microstruct, Nanjing 210093, Peoples R China. RP Huang, XR (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. EM xrhuang@aps.anl.gov NR 23 TC 42 Z9 42 U1 3 U2 16 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 2007 VL 76 IS 3 AR 035802 DI 10.1103/PhysRevA.76.035802 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 215CN UT WOS:000249786000190 ER PT J AU Rohringer, N Santra, R AF Rohringer, Nina Santra, Robin TI X-ray nonlinear optical processes using a self-amplified spontaneous emission free-electron laser SO PHYSICAL REVIEW A LA English DT Article ID MULTIPHOTON IONIZATION PROCESSES; MULTIPLE-PHOTON PROCESSES; 2-PHOTON ABSORPTION; COMPTON-SCATTERING; CROSS-SECTIONS; ATOM CLUSTERS; NEON ATOM; K-SHELL; COHERENCE; FIELD AB In contrast to the long-wavelength regime, x-ray nonlinear optical processes are characterized in general by sequential single-photon single-electron interactions. Despite this fact, the sequential absorption of multiple x-ray photons depends on the statistical properties of the radiation field. Treating the x rays generated by a self-amplified spontaneous emission free-electron laser as fully chaotic, a quantum-mechanical analysis of inner-shell two-photon absorption is performed. It is demonstrated that double-core-hole formation via x-ray two-photon absorption is enhanced by chaotic photon statistics. Numerical calculations using rate equations illustrate the impact of field chaoticity on x-ray nonlinear ionization of helium and neon for photon energies near 1 keV. In the case of neon, processes are discussed that involve up to seven photons. Assuming an x-ray coherence time of 2.6 fs, double-core-hole formation in neon is found to be statistically enhanced by about 30% at an intensity of 10(16) W/cm(2). C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Rohringer, N (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Rohringer, Nina/B-8030-2012; Santra, Robin/E-8332-2014; Rohringer, Nina/N-3238-2014 OI Santra, Robin/0000-0002-1442-9815; Rohringer, Nina/0000-0001-7905-3567 NR 68 TC 89 Z9 89 U1 3 U2 20 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 EI 1094-1622 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 2007 VL 76 IS 3 AR 033416 DI 10.1103/PhysRevA.76.033416 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 215CN UT WOS:000249786000119 ER PT J AU Savukov, IM AF Savukov, I. M. TI Quasicontinuum relativistic many-body perturbation theory photoionization cross sections of Na, K, Rb, and Cs SO PHYSICAL REVIEW A LA English DT Article ID CORRELATION-POTENTIAL METHOD; ALKALI-METAL ATOMS; HYPERFINE-STRUCTURE; ELECTRON; PHOTOABSORPTION; AMPLITUDES; SODIUM AB Calculations of photoionization cross sections for alkali-metal atoms are carried out in the framework of relativistic many-body perturbation theory (RMBPT) using quasicontinuum B-spline orbitals. All third-order terms are included, in contrast to previous calculations based on either random-phase approximation (RPA), Brueckner orbitals, or their combination. The particular advantage of quasicontinuum states is that high-order MBPT codes do not require modification for applications to the photoionization problem. The agreement with experiment is improved compared to RPA and Dirac-Hartree-Fock approximations. The results also exhibit close form invariance. The presented formalism can be extended to other photoionizing transitions. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Savukov, IM (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM isavukov@lanl.edu OI Savukov, Igor/0000-0003-4190-5335 NR 18 TC 7 Z9 7 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD SEP PY 2007 VL 76 IS 3 AR 032710 DI 10.1103/PhysRevA.76.032710 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 215CN UT WOS:000249786000092 ER PT J AU Adriano, C Lora-Serrano, R Giles, C de Bergevin, F Lang, JC Srajer, G Mazzoli, C Paolasini, L Pagliuso, PG AF Adriano, C. Lora-Serrano, R. Giles, C. de Bergevin, F. Lang, J. C. Srajer, G. Mazzoli, C. Paolasini, L. Pagliuso, P. G. TI Magnetic structure of Sm2IrIn8 determined by x-ray resonant magnetic scattering SO PHYSICAL REVIEW B LA English DT Article ID HEAVY-FERMION MATERIALS; EXCHANGE SCATTERING; POLARIZATION DEPENDENCE; SUPERCONDUCTIVITY; CERHIN5; ANTIFERROMAGNETS; INDIUM AB The magnetic structure of the intermetallic antiferromagnet Sm2IrIn8 was determined using x-ray resonant magnetic scattering. Below T-N=14.2 K, Sm2IrIn8 has a commensurate antiferromagnetic structure with a propagation vector eta=(1/2,0,0). The Sm magnetic moments lie in the ab plane and are rotated roughly 18 degrees away from the a axis. The magnetic structure of this compound was obtained by measuring the strong dipolar resonant peak whose enhancement was of over 2 orders of magnitude at the L-2 edge. At the L-3 edge, both quadrupolar and dipolar features were observed in the energy line shape. The magnetic structure and properties of Sm2IrIn8 are found to be consistent with the general trend already seen for the Nd-, Tb-, and the Ce-based compounds from the RmMnIn3m+2n family (R=rare earth; M=Rh or Ir; m=1,2; n=0,1), where the crystalline electrical field effects determine the direction of magnetic moments and the T-N evolution in the series. The measured Neel temperature for Sm2IrIn8 is slightly suppressed when compared to the T-N of the parent cubic compound SmIn3. C1 Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Adriano, C (reprint author), Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. EM cadriano@ifi.unicamp.br RI Pagliuso, Pascoal/C-9169-2012; Mazzoli, Claudio/J-4360-2012; Giles, Carlos/E-2878-2012; Lora Serrano, Raimundo/L-6307-2016; Inst. of Physics, Gleb Wataghin/A-9780-2017 OI Giles, Carlos/0000-0001-8373-7398; Lora Serrano, Raimundo/0000-0003-3777-2170; NR 55 TC 13 Z9 13 U1 1 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 104515 DI 10.1103/PhysRevB.76.104515 PG 8 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300098 ER PT J AU Alapati, SV Johnson, JK Sholl, DS AF Alapati, Sudhakar V. Johnson, J. Karl Sholl, David S. TI Stability analysis of doped materials for reversible hydrogen storage in destabilized metal hydrides SO PHYSICAL REVIEW B LA English DT Article ID N-H SYSTEM; MAGNESIUM HYDRIDE; LIBH4; DECOMPOSITION; AMIDE; MGH2; LIH AB Thermodynamic calculations with first principles density functional theory are carried out to estimate the free energies of various doped metal hydride systems. We consider doped destabilized hydride reactions of the form X1-xYxH2+2LiBH(4)-> X1-xYxB2+2LiH+4H(2), where X,Y=Mg, Sc, or Ti. We have evaluated the zero temperature enthalpies, without inclusion of zero point energies, for 18 different doped systems. Most systems are found to be unstable with respect to phase separation at 0 K. We have included configurational entropy to estimate the temperature at which the doped systems become stable. Most doped compounds are estimated to remain unstable with respect to phase segregation up to temperatures that are too high to be of practical interest. We have computed the phonon density of states for the X=Sc, Y=Ti system and find that this system is stable with respect to phase segregation at T>435 K. We have computed the van't Hoff plot for Sc7H16Ti+16LiBH(4)-> Sc7B16Ti+16LiH+32H(2) and compared this to the undoped reaction. Doping increases the vapor pressure at a given temperature, but only by a factor of 2-4. C1 Carnegie Mellon Univ, Dept Chem Engn, Pittsburgh, PA 15213 USA. Univ Pittsburgh, Dept Chem & Petr Engn, Pittsburgh, PA 15261 USA. Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. RP Sholl, DS (reprint author), Carnegie Mellon Univ, Dept Chem Engn, Pittsburgh, PA 15213 USA. EM sholl@andrew.cmu.edu RI Mahalingam, Arjun/G-8586-2011; Johnson, Karl/E-9733-2013 OI Johnson, Karl/0000-0002-3608-8003 NR 38 TC 24 Z9 24 U1 2 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 104108 DI 10.1103/PhysRevB.76.104108 PG 8 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300027 ER PT J AU Amara, H Latil, S Meunier, V Lambin, P Charlier, JC AF Amara, H. Latil, S. Meunier, V. Lambin, Ph. Charlier, J.-C. TI Scanning tunneling microscopy fingerprints of point defects in graphene: A theoretical prediction SO PHYSICAL REVIEW B LA English DT Article ID WALLED CARBON NANOTUBES; ELECTRONIC-STRUCTURE; GRAPHITE SURFACES; ION IRRADIATION; SIMULATION; ENERGETICS; STATES; CONDUCTANCE; COALESCENCE; COMPUTATION AB Scanning tunneling microscopy (STM) is one of the most appropriate techniques to investigate the atomic structure of carbon nanomaterials. However, the experimental identification of topological and nontopological modifications of the hexagonal network of sp(2) carbon nanostructures remains a great challenge. The goal of the present theoretical work is to predict the typical electronic features of a few defects that are likely to occur in sp(2) carbon nanostructures, such as atomic vacancy, divacancy, adatom, and Stone-Wales defect. The modifications induced by those defects in the electronic properties of the graphene sheet are investigated using first-principles calculations. In addition, computed constant-current STM images of these defects are calculated within a tight-binding approach in order to facilitate the interpretation of STM images of defected carbon nanostructures. C1 Fac Univ Notre Dame Paix, Phys Solide Lab, B-5000 Namur, Belgium. Catholic Univ Louvain, PCPM, B-1348 Louvain, Belgium. Catholic Univ Louvain, CERMIN, B-1348 Louvain, Belgium. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Amara, H (reprint author), Fac Univ Notre Dame Paix, Phys Solide Lab, Rue Bruxelles 61, B-5000 Namur, Belgium. RI Meunier, Vincent/F-9391-2010; Amara, Hakim/H-6923-2012; OI Meunier, Vincent/0000-0002-7013-179X; Lambin, Philippe/0000-0001-8051-042X NR 62 TC 92 Z9 92 U1 3 U2 69 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 11 AR 115423 DI 10.1103/PhysRevB.76.115423 PG 10 WC Physics, Condensed Matter SC Physics GA 215CR UT WOS:000249786400114 ER PT J AU Asti, G Ghidini, M Mulazzi, M Pellicelli, R Solzi, M Chesnel, K Marty, A AF Asti, G. Ghidini, M. Mulazzi, M. Pellicelli, R. Solzi, M. Chesnel, K. Marty, A. TI Nucleation of weak stripe domains: Determination of exchange and anisotropy thermal variation SO PHYSICAL REVIEW B LA English DT Article ID PERPENDICULAR MAGNETIC-ANISOTROPY; SPIN-WAVE RESONANCE; THIN-FILMS; TEMPERATURE AB The phenomenon of stripe domain nucleation is deeply investigated both theoretically and experimentally in FePd films by the rigorous micromagnetic theory of domain nucleation and x-ray resonant magnetic scattering. The critical domain width and the nucleation field are determined by measuring the magnetic satellite peak position and integrated intensities in a wide temperature interval up to 400 degrees C (0.9T(c)) at varying in-plane magnetic fields for each temperature value. We develop and demonstrate a procedure that allows us to determine directly from the micromagnetic treatment the exchange stiffness constant A and the first order anisotropy constant K-u as a function of temperature. The proposed procedure, based on linearized micromagnetic equations at the critical field, is valid for magnetic films with perpendicular magnetic anisotropy, and is therefore effective to measure A and K-u in a technologically relevant class of materials. C1 Univ Parma, CNISM, I-43100 Parma, Italy. Univ Parma, Dipartimento Fis, I-43100 Parma, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Ligh Source Div, Berkeley, CA 94720 USA. CEA, Dept Rech Fondamentale Matiere Condensee, Grenoble 9, France. RP Asti, G (reprint author), Univ Parma, CNISM, Viale GP Usberti 7-A, I-43100 Parma, Italy. RI Solzi, Massimo/C-5309-2008; Ghidini, Massimo/L-5848-2015; marty, alain/H-7941-2014 OI Solzi, Massimo/0000-0002-9912-4534; Ghidini, Massimo/0000-0002-1905-2455; marty, alain/0000-0001-5709-6945 NR 26 TC 4 Z9 4 U1 1 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 9 AR 094414 DI 10.1103/PhysRevB.76.094414 PG 8 WC Physics, Condensed Matter SC Physics GA 215CO UT WOS:000249786100060 ER PT J AU Bennett, PA Chobanian, J Flege, JI Sutter, E Sutter, P AF Bennett, P. A. Chobanian, J. Flege, J. I. Sutter, E. Sutter, P. TI Surface thermomigration of nanoscale Pt-Si droplets on stepped Si(100) SO PHYSICAL REVIEW B LA English DT Article ID STRAINED ISLANDS; GROWTH; MIGRATION; SILICON; SI(001); NANOWIRES AB The motion of Pt-Si liquid nanodroplets and their interaction with atomic steps on Si(100) has been studied using low-energy electron microscopy. Submicron droplets migrate across the surface in the direction of the lateral temperature gradient as demonstrated by overlain maps of migration velocity and sample temperature. The thermal migration motion is opposed by a drag force normal to substrate steps, which strongly deflects smaller droplets to move parallel to step edges but hardly affects larger ones. In addition, steps are dragged along by moving droplets before eventually depinning. The resulting curved steps can create "roadways" that collect droplets and guide their motion, resulting in a non-Ostwald coarsening process involving guided collision and coalescence. C1 Arizona State Univ, Dept Phys, Tempe, AZ 85287 USA. Arizona State Univ, Sch Mat, Tempe, AZ 85287 USA. Brookhaven Natl Lab, Ctr Funct Nanomat, Upton, NY 11973 USA. RP Bennett, PA (reprint author), Arizona State Univ, Dept Phys, Tempe, AZ 85287 USA. EM peter.bennett@asu.edu RI Flege, Jan Ingo/J-6354-2012 OI Flege, Jan Ingo/0000-0002-8346-6863 NR 21 TC 4 Z9 4 U1 1 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 12 AR 125410 DI 10.1103/PhysRevB.76.125410 PG 6 WC Physics, Condensed Matter SC Physics GA 215CS UT WOS:000249786500070 ER PT J AU Bridges, F Downs, C O'Brien, T Jeong, IK Kimura, T AF Bridges, F. Downs, C. O'Brien, T. Jeong, Il-K Kimura, T. TI Limitations on the extent of off-center displacements in TbMnO3 from EXAFS measurements SO PHYSICAL REVIEW B LA English DT Article AB We present extended x-ray-absorption fine structure (EXAFS) data at the Mn K and Tb L-3 edges that provide upper limits on the possible displacements of any atoms in TbMnO3. The displacements must be less than 0.005-0.01 angstrom for all atoms, which eliminates the possibility of moderate distortions (0.02 angstrom) with a small c-axis component, but for which the displacements in the ab plane average to zero. Assuming the polarization arises from a displacement of the O2 atoms along the c axis, the measured polarization then leads to an O2 displacement that is at least 6 x 10(-4) angstrom, well below our experimental limit. Thus, a combination of the EXAFS and the measured electrical polarization indicate that the atomic displacements likely lie in the range 6 x 10(-4)-5 x 10(-3) angstrom. C1 Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Pusan Natl Univ, Res Ctr Dielect & Adv Matter Phys, Pusan 609735, South Korea. RP Bridges, F (reprint author), Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. RI O'Brien, Travis/M-5250-2013 OI O'Brien, Travis/0000-0002-6643-1175 NR 3 TC 5 Z9 5 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 9 AR 092109 DI 10.1103/PhysRevB.76.092109 PG 4 WC Physics, Condensed Matter SC Physics GA 215CO UT WOS:000249786100009 ER PT J AU Chubukov, AV Tsvelik, AM AF Chubukov, A. V. Tsvelik, A. M. TI Spin-liquid model of the sharp drop in resistivity in superconducting La1.85Ba0.125CuO4 SO PHYSICAL REVIEW B LA English DT Article AB We use the phenomenological model proposed in our previous paper [Phys. Rev. Lett. 98, 237001 (2007)] to analyze the magnetic-field dependence of the onset temperature for two-dimensional fluctuating superconductivity T**(H). We demonstrate that the slope of T**(H) progressively goes down as H increases, such that the upper critical field progressively increases as T decreases. Quantitative agreement with the recent measurements of T**(H) in La1.85Ba0.125CuO4 is achieved for the same parameter value as was derived in our previous publication from the analysis of the electron self-energy. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Brookhaven Natl Lab, Dept Condensed Matter Phys & Mat Sci, Upton, NY 11973 USA. RP Chubukov, AV (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. NR 9 TC 10 Z9 10 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 100509 DI 10.1103/PhysRevB.76.100509 PG 4 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300019 ER PT J AU Diaz, J Monteiro, OR Hussain, Z AF Diaz, J. Monteiro, O. R. Hussain, Z. TI Structure of amorphous carbon from near-edge and extended x-ray absorption spectroscopy SO PHYSICAL REVIEW B LA English DT Article ID CATHODIC ARC DEPOSITION; DIAMOND-LIKE CARBON; AB-INITIO CALCULATION; ELECTRON-ENERGY-LOSS; FINE-STRUCTURE; MULTIPLE-SCATTERING; THIN-FILMS; GRAPHITE; VACUUM; STRESS AB Mechanically hard (ha-C) and soft (sa-C) amorphous carbon films of 2.9 and 2.2 g cm(-3) approximate densities were prepared by filtered cathodic arc deposition and analyzed by near-edge x-ray absorption spectroscopy (NEXAFS) and extended x-ray absorption spectroscopy (EXAFS) to determine their structure. The analysis observed an insignificant level of pi bond conjugation in both kind of films. EXAFS distinguished two types of atomic environments in them: one semiordered with well defined bond lengths, and the other with so strong bond disorder that its contribution to EXAFS was undetectable. The proportion of atoms in the semiordered atomic environments was of less than 40% in both films. Their bond lengths were similar to those of diamond in the ha-C films and to graphite in the sa-C. NEXAFS spectra analysis was based on the linear relation between sigma(*) energy and bond length. It served to quantify the proportion of sp(3) bonded atoms in a-C, to deduce the average bond length of the atoms undetected by EXAFS, and to determine the level of pi bond conjugation in the films. The sp(3) concentration estimated with the proposed method was of 44% in the ha-C films and 10% in the sa-C films. These values were consistent with the EXAFS results, but disagreed with those obtained based on the traditional pi(*)/sigma(*) intensity ratio method which overestimated sp(3) concentrations. Annealing of the ha-C films up to its almost complete graphitization caused a gradual reduction in bond length of the semiordered environments with no differentiation between two phases, diamondlike and graphitelike, at any temperature. This result support models that explain sp(3) bond promotion in a-C as caused by the high compressive stress attained by a strongly disordered sp(2) dense structure during film deposition. C1 Univ Oviedo, Dept Fis, E-33007 Oviedo, Spain. Lawrence Berkeley Natl Lab, Plasma Applicat Grp, Berkeley, CA 92740 USA. Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 92740 USA. RP Diaz, J (reprint author), Univ Oviedo, Dept Fis, Ave Calvo S-N, E-33007 Oviedo, Spain. EM javidiaz@condmat.uniovi.es RI Diaz, Javier/F-2381-2016 NR 48 TC 18 Z9 18 U1 1 U2 10 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 9 AR 094201 DI 10.1103/PhysRevB.76.094201 PG 12 WC Physics, Condensed Matter SC Physics GA 215CO UT WOS:000249786100042 ER PT J AU Duque, JGS Urbano, RR Venegas, PA Pagliuso, PG Rettori, C Fisk, Z Oseroff, SB AF Duque, J. G. S. Urbano, R. R. Venegas, P. A. Pagliuso, P. G. Rettori, C. Fisk, Z. Oseroff, S. B. TI Exchange and crystal field effects in the ESR spectra of Eu(2+) in LaB(6) SO PHYSICAL REVIEW B LA English DT Article ID ELECTRON-SPIN-RESONANCE; INTERMETALLIC COMPOUNDS; SINGLE-CRYSTALS; PARAMAGNETIC-RESONANCE; CONDUCTION ELECTRONS; RARE-EARTHS; VALENCE COMPOUND; NOBLE-METALS; GD3+; ALLOYS AB Electron spin resonance of Eu(2+) (4f(7), S=7/2) in a La hexaboride (LaB(6)) single crystal shows a single anisotropic Dysonian resonance. From the observed negative g shift of the resonance, it is inferred that the Eu(2+) ions are covalent exchange coupled to the B 2p-like host conduction electrons. From the anisotropy of the spectra (linewidth and field for resonance), we found that the S ground state of Eu(2+) ions experience a cubic crystal field of a negative fourth order crystal field parameter (CFP), b(4)=-11.5(2.0) Oe, in agreement with the negative fourth order CFP, A(4), found for the non-S ground state R hexaborides. These results support covalency as the dominant contribution to the fourth order CFP for the whole R hexaboride family. C1 Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Estadual Paulista, Dipartimento Fis, BR-17033360 Bauru, SP, Brazil. Univ Calif Irvine, Dept Phys, Irvine, CA 92697 USA. San Diego State Univ, San Diego, CA 92182 USA. RP Duque, JGS (reprint author), Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. RI Rettori, Carlos/C-3966-2012; Pagliuso, Pascoal/C-9169-2012; Urbano, Ricardo/F-5017-2012; Venegas, Pablo/J-2108-2012; Inst. of Physics, Gleb Wataghin/A-9780-2017 OI Rettori, Carlos/0000-0001-6692-7915; NR 68 TC 2 Z9 2 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 12 AR 125114 DI 10.1103/PhysRevB.76.125114 PG 6 WC Physics, Condensed Matter SC Physics GA 215CS UT WOS:000249786500023 ER PT J AU Essler, FHL Kuzmenko, T Zaliznyak, IA AF Essler, F. H. L. Kuzmenko, T. Zaliznyak, I. A. TI Luttinger liquid coupled to quantum spins: Flow equation approach to the Kondo necklace model SO PHYSICAL REVIEW B LA English DT Article ID RENORMALIZATION-GROUP; LATTICE MODEL; GAP-FORMATION; CHAIN; ANTIFERROMAGNET; HAMILTONIANS; DYNAMICS; PHASE; TRANSITIONS; IMPURITY AB We study a lattice realization of a Luttinger liquid interacting with quantum spins in terms of an antiferromagnetic S=1/2 Heisenberg chain, where each spin is also coupled to a sigma=1/2 Kondo spin degree of freedom. This model describes the low-energy spin dynamics in quasi-one-dimensional materials, where the electronic spins of the magnetic ions interact with those of impurities, nuclei, and possibly other spin species present in their environment. For large ferromagnetic and antiferromagnetic Kondo interaction J('), there are two phases corresponding to an effective spin-1 Heisenberg chain and a dimerized spin-1/2 ladder, respectively. For weak Kondo interaction, we establish that the Kondo interaction drives the system to a strong coupling regime. This suggests that J '=0 is the only critical point in the system. C1 Univ Oxford, Rudolf Peierls Ctr Theoret Phys, Oxford OX1 3NP, England. Brookhaven Natl Lab, CMPMSD, Upton, NY 11973 USA. RP Essler, FHL (reprint author), Univ Oxford, Rudolf Peierls Ctr Theoret Phys, 1 Keble Rd, Oxford OX1 3NP, England. RI Zaliznyak, Igor/E-8532-2014 OI Zaliznyak, Igor/0000-0002-9886-3255 NR 49 TC 4 Z9 4 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 11 AR 115108 DI 10.1103/PhysRevB.76.115108 PG 9 WC Physics, Condensed Matter SC Physics GA 215CR UT WOS:000249786400027 ER PT J AU Faleev, SV Leonard, F AF Faleev, Sergey V. Leonard, Francois TI Electron transport through pi-stacked molecular multilayers: Metal-semiconductor transition SO PHYSICAL REVIEW B LA English DT Article ID FIELD-EFFECT TRANSISTOR; ORGANIC ADSORBATES; CONDUCTANCE; OLIGOTHIOPHENES; POLYTHIOPHENE; LUMINESCENCE; AG(111); FILMS AB We present a theoretical study of electron transport in pi-stacked polythiophene multilayers (with varying number of layers L) sandwiched between Au(111) electrodes in a geometry of flat molecular layers lying parallel to the electrode surface, as suggested by recent experiments. We use a method based on the local density approximation of density functional theory and implemented in the framework of the tight-binding linear muffin-tin orbital approach in its atomic sphere approximation. A fully atomistic description of the electrodes and the nanosystem is used, and the self-consistent charge and electrostatic potential for the system under applied bias are calculated using the nonequilibrium Green's function approach. For a small number of layers, metal-induced gap states render the molecular film metallic, while for thicker films, the conductance decreases exponentially with the number of layers, sigma approximate to G(0) exp[-0.81(L-3.4)], indicating semiconductorlike behavior; the transition between these two regimes occurs at a film thickness of 20 A (L approximate to 6). This length scale originates from the decay length of the gap states (4.24 A) and the "band bending" in the multilayer. For L=1, the current depends linearly on applied voltage, while at L > 1, current is nonlinear, reflecting strong bias and energy dependence of the transmission function due to formation of the band gap near the Fermi energy. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Faleev, SV (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. EM sfaleev@sandia.gov NR 25 TC 1 Z9 1 U1 1 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 12 AR 125108 DI 10.1103/PhysRevB.76.125108 PG 6 WC Physics, Condensed Matter SC Physics GA 215CS UT WOS:000249786500017 ER PT J AU Herrero-Albillos, J Bartolome, F Garcia, LM Young, AT Funk, T Campo, J Cuello, GJ AF Herrero-Albillos, Julia Bartolome, Fernando Garcia, Luis M. Young, Anthony T. Funk, Tobias Campo, Javier Cuello, Gabriel J. TI Observation of a different magnetic disorder in ErCo2 SO PHYSICAL REVIEW B LA English DT Article ID ITINERANT-ELECTRON METAMAGNETISM; EARTH INTERMETALLIC COMPOUNDS; RCO2 LAVES PHASES; RARE-EARTH; CIRCULAR-DICHROISM; POLARIZED-NEUTRON; SUSCEPTIBILITY MAXIMUM; COBALT COMPOUNDS; HIGH-PRESSURE; TRANSITION AB X-ray magnetic circular dichroism (XMCD), small-angle neutron scattering (SANS), and ac magnetic susceptibility (chi(ac)) measurements as a function of temperature and magnetic field on the Laves phase compound ErCo2 are presented. The results allow one to investigate in detail the ErCo2 paramagnetic phase. The XMCD data reveal an extended region on the phase diagram where the net magnetization of the Er and Co sublattices are oriented in opposite directions at temperatures well above the ferrimagnetic ordering temperature. The complete characterization of the phenomenon by means of SANS and chi(ac) measurements allows us to propose the occurrence of short-range magnetic order, which we described and systematically studied and which we denote as parimagnetism. The origin of the parimagnetism is analyzed in terms of the different magnetic interactions present in the system. We conclude that parimagnetism in ErCo2 is driven by the formation of Co magnetic clusters which are ferromagnetically coupled within the paramagnetic phase. C1 Univ Zaragoza, CSIC, Inst Ciencia Mat Aragon, E-50009 Zaragoza, Spain. Univ Zaragoza, CSIC, Dept Fis Mat Condensada, E-50009 Zaragoza, Spain. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. UCSF, Phys Res Lab, San Francisco, CA 94107 USA. Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. RP Herrero-Albillos, J (reprint author), Univ Zaragoza, CSIC, Inst Ciencia Mat Aragon, Pedro Cerbuna 12, E-50009 Zaragoza, Spain. EM julia.herrero@unizar.es RI Herrero-Albillos, Julia/B-9837-2009; Cuello, Gabriel/C-5831-2009; D2B, Instrument/F-1072-2012; Herrero-Albillos, Julia/I-5462-2012; Bartolome, Fernando/K-1700-2014; Campo Ruiz, Jesus Javier/L-6558-2014 OI Herrero-Albillos, Julia/0000-0002-0901-8341; Cuello, Gabriel/0000-0003-3844-0602; Herrero-Albillos, Julia/0000-0002-0901-8341; Bartolome, Fernando/0000-0002-0047-1772; Campo Ruiz, Jesus Javier/0000-0002-3600-1721 NR 70 TC 33 Z9 33 U1 1 U2 24 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 9 AR 094409 DI 10.1103/PhysRevB.76.094409 PG 10 WC Physics, Condensed Matter SC Physics GA 215CO UT WOS:000249786100055 ER PT J AU Hoyt, JJ AF Hoyt, J. J. TI Molecular dynamics study of equilibrium concentration profiles and the gradient energy coefficient in Cu-Pb nanodroplets SO PHYSICAL REVIEW B LA English DT Article ID PHASE-FIELD MODEL; AL-ZN ALLOYS; SPINODAL DECOMPOSITION; SYNCHROTRON RADIATION; MELTING TEMPERATURE; SIZE DEPENDENCE; GOLD PARTICLES; CRITICAL-POINT; SOLIDIFICATION; SIMULATION AB Atomistic simulations were used to equilibrate the concentration profiles in 5.3 nm liquid droplets for an embedded atom method model of Cu-Pb. The strong tendency of Pb to surface segregate establishes a nonuniform profile, which decays over a length comparable to the particle radius. With the free energy vs composition determined from separate Monte Carlo simulations, the composition profile can be analyzed in terms of the Cahn-Hilliard diffuse interface model and the gradient energy coefficient, kappa, can be obtained. Results from three different temperatures indicate that kappa lies in the range 1.0-1.4x10(-10) J/m. In addition to the gradient energy coefficient, various aspects of phase equilibria at the nanoscale have been investigated. The critical point of the liquid-liquid miscibility was found to decrease by approximate to 50 K for the 5.3 nm particle size, the melting point of pure Cu is suppressed by approximate to 110 K, and the liquidus slope is shallower than that of the bulk system. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hoyt, JJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 46 TC 5 Z9 5 U1 3 U2 15 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 9 AR 094102 DI 10.1103/PhysRevB.76.094102 PG 7 WC Physics, Condensed Matter SC Physics GA 215CO UT WOS:000249786100029 ER PT J AU Hu, RW Mitrovic, VF Petrovic, C AF Hu, Rongwei Mitrovic, V. F. Petrovic, C. TI Anisotropy in the magnetic and electrical transport properties of Fe1-xCrxSb2 SO PHYSICAL REVIEW B LA English DT Article ID CRYSTAL-STRUCTURE; INSULATOR-TRANSITION; MARCASITE; FESB2 AB We have investigated anisotropy in magnetic and electrical transport properties of Fe1-xCrxSb2 (0 <= x <= 1) single crystals. The magnetic ground state of the system evolves from paramagnetic to antiferromagnetic with gradual substitution of Fe with Cr. Anisotropy in electrical transport diminishes with increased Cr substitution and fades away by x = 0.5. We find that the variable range hopping conduction mechanism dominates at low temperatures for 0.4 <= x <= 0.75. C1 Brookhaven Natl Lab, Dept Mat Sci, Upton, NY 11973 USA. Brown Univ, Dept Phys, Providence, RI 02912 USA. RP Hu, RW (reprint author), Brookhaven Natl Lab, Dept Mat Sci, Upton, NY 11973 USA. RI Petrovic, Cedomir/A-8789-2009; Hu, Rongwei/E-7128-2012 OI Petrovic, Cedomir/0000-0001-6063-1881; NR 19 TC 20 Z9 20 U1 1 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 11 AR 115105 DI 10.1103/PhysRevB.76.115105 PG 5 WC Physics, Condensed Matter SC Physics GA 215CR UT WOS:000249786400024 ER PT J AU Karaiskaj, D Mascarenhas, A Klem, JF Volz, K Stolz, W Adamcyk, M Tiedje, T AF Karaiskaj, D. Mascarenhas, A. Klem, J. F. Volz, K. Stolz, W. Adamcyk, M. Tiedje, T. TI Excitons bound to nitrogen pairs in GaAs as seen by photoluminescence of high spectral and spatial resolution SO PHYSICAL REVIEW B LA English DT Article ID GAP; LUMINESCENCE; GAAS1-XNX; ALLOY AB High resolution photoluminescence (PL) spectroscopy was performed on high quality bulk GaAs, lightly doped with the nitrogen isoelectronic impurity. The shallowest nitrogen pair bound exciton center labeled as X-1 revealed a total of six transitions. The photoluminescence lines from a small ensemble of nitrogen centers showed polarization dependent intensity. High spectral resolution PL spectroscopy was combined with confocal spectroscopy experiments performed on a GaAs:N/AlGaAs heterostructure. The high spatial resolution achieved by this technique enables us to localize and examine individual nitrogen bound excitons. Similar spectral structure and polarization dependence was observed for individual N-pair centers in GaAs. Both techniques support the C-2v symmetry of such isoelectronic impurity centers. The comparison between the PL spectra from an ensemble of nitrogen pairs and individual centers demonstrate the ability of the single impurity technique to lift the orientational degeneracy. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Marburg, Fachbereich Phys, D-35032 Marburg, Germany. Univ Marburg, Wissensch Zentrum Mat Wissensch, D-35032 Marburg, Germany. Univ British Columbia, Dept Phys & Astron, AMPEL, Vancouver, BC V6T 1Z4, Canada. RP Karaiskaj, D (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 20 TC 19 Z9 19 U1 0 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 12 AR 125209 DI 10.1103/PhysRevB.76.125209 PG 5 WC Physics, Condensed Matter SC Physics GA 215CS UT WOS:000249786500035 ER PT J AU Kim, C Park, SR Leem, CS Song, DJ Jin, HU Kim, HD Ronning, F Kim, C AF Kim, Chul Park, S. R. Leem, C. S. Song, D. J. Jin, H. U. Kim, H.-D. Ronning, F. Kim, C. TI Electron removal self-energy and its application to Ca2CuO2Cl2 SO PHYSICAL REVIEW B LA English DT Article ID ANGLE-RESOLVED PHOTOEMISSION; MEAN-FIELD THEORY; FERMION SYSTEMS; DISPERSION AB We propose using the self-energy defined for the electron removal Green's function. Starting from the electron removal Green's function, we obtained expressions for the electron removal self-energy Sigma(ER)(k,omega) that are applicable for nonquasiparticle photoemission spectral functions from a single band system. Our method does not assume momentum independence and produces the self-energy in the full k-omega space. The method is applied to the angle resolved photoemission data from Ca2CuO2Cl2, and the result is found to be compatible with the self-energy value from the peak width of sharp features. The self-energy is found to be only weakly k dependent. In addition, the Im Sigma shows a maximum at around 1 eV where the high energy kink is located. C1 Yonsei Univ, Inst Phys & Appl Phys, Seoul 120749, South Korea. POSTECH, Pohang Accelerator Lab, Beamline Res Div, Pohang 790784, South Korea. Los Alamos Natl Lab, MPA Div 10, Los Alamos, NM 87545 USA. RP Kim, C (reprint author), Yonsei Univ, Inst Phys & Appl Phys, Seoul 120749, South Korea. EM cykim@phya.yonsei.ac.kr OI Ronning, Filip/0000-0002-2679-7957 NR 30 TC 9 Z9 9 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 104505 DI 10.1103/PhysRevB.76.104505 PG 5 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300088 ER PT J AU Kolesnikov, AI Yang, HX Shi, YG Li, JQ Walton, RI Li, JC AF Kolesnikov, A. I. Yang, H. X. Shi, Y. G. Li, J. Q. Walton, R. I. Li, J. C. TI Observation of two O-H covalent bonds of water in the Na0.3CoO2 center dot 1.3H(2)O superconductor by inelastic neutron spectroscopy SO PHYSICAL REVIEW B LA English DT Article AB The vibrational dynamics of pure H2O and isotopically substituted HDO water in a Na0.3CoO2 center dot 1.3H(2)O layered compound was studied using neutron spectroscopy. The obtained results showed that water in the ab plane of the hexagonal structure exhibits intermolecular translational vibrations and intramolecular O-H stretching modes similar to those in bulk water, but the vibrations along the z direction are different-the corresponding hydrogen bond between the water molecule and the CoO2 layer is much weaker than between water molecules in the water layer. These data revealed two O-H covalent bonds for water in Na0.3CoO2 center dot 1.3H(2)O superconductor which differ in strength by about 18%. C1 Argonne Natl Lab, Intense Pulsed Neutron Source Div, Argonne, IL 60439 USA. Chinese Acad Sci, Inst Phys, Beijing Natl Lab Condensed Matter Phys, Beijing 100080, Peoples R China. Univ Warwick, Dept Chem, Coventry CV4 7AL, W Midlands, England. Univ Manchester, Dept Phys & Astron, Manchester M60 1QD, Lancs, England. RP Kolesnikov, AI (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source Div, 9700 S Cass Ave, Argonne, IL 60439 USA. EM akolesnikov@anl.gov RI Walton, Richard/C-2058-2009; Kolesnikov, Alexander/I-9015-2012 OI Kolesnikov, Alexander/0000-0003-1940-4649 NR 11 TC 1 Z9 1 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 9 AR 092302 DI 10.1103/PhysRevB.76.092302 PG 3 WC Physics, Condensed Matter SC Physics GA 215CO UT WOS:000249786100014 ER PT J AU Konik, RM Rice, TM AF Konik, R. M. Rice, T. M. TI Orbital dependence of quasiparticle lifetimes in Sr2RuO4 SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTOR SR2RUO4 AB Using a phenomenological Hamiltonian, we investigate the quasiparticle lifetimes and dispersions in the three low energy bands gamma, beta, and alpha of Sr2RuO4. Couplings in the Hamiltonian are fixed so as to produce the mass renormalization as measured in magneto-oscillation experiments. We thus find reasonable agreement in all bands between our computed lifetimes and those measured in angle resolved photoemission spectroscopy experiments by Kidd [Phys. Rev. Lett. 94, 107003 (2005)] and Ingle [Phys. Rev. B 72, 205114 (2005)]. In comparing the computed to measured quasiparticle dispersions, we, however, find good agreement in the alpha band alone. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. ETH, Inst Theoret Phys, CH-8093 Zurich, Switzerland. RP Konik, RM (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Konik, Robert/L-8076-2016 OI Konik, Robert/0000-0003-1209-6890 NR 17 TC 4 Z9 4 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 104501 DI 10.1103/PhysRevB.76.104501 PG 8 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300084 ER PT J AU Konstantinidis, NP AF Konstantinidis, N. P. TI Unconventional magnetic properties of the icosahedral symmetry antiferromagnetic Heisenberg model SO PHYSICAL REVIEW B LA English DT Article ID LATTICE; SUPERCONDUCTIVITY; FULLERENES; C-60 AB The antiferromagnetic Heisenberg model on icosahedral symmetry I-h fullerene clusters exhibits unconventional magnetic properties despite the lack of anisotropic interactions. At the classical level, and for number of sites n <= 720, the magnetization has two discontinuities in an external magnetic field, except from the dodecahedron where it has three, emphasizing the role of frustration introduced by the pentagons in the unusual magnetic properties. For spin magnitude s(i)=1/2, there is a discontinuity of quantum character close to saturation for n <= 80. This common magnetic behavior indicates that it is a generic feature of I-h fullerene clusters, irrespective of n. C1 Iowa State Univ, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. RP Konstantinidis, NP (reprint author), Iowa State Univ, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. NR 20 TC 16 Z9 16 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 104434 DI 10.1103/PhysRevB.76.104434 PG 5 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300079 ER PT J AU Kopnin, NB Galperin, YM Vinokur, V AF Kopnin, N. B. Galperin, Y. M. Vinokur, V. TI Low-voltage current noise in long quantum superconductor/insulator/normal-metal/insulator/superconductor junctions SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTING WEAK LINKS; POINT CONTACTS; GAP STRUCTURE; SUPERCURRENT; TRANSPORT AB The current noise in long superconductor/insulator/normal-metal/insulator/superconductor junctions at low temperatures is sensitive to the population of the subgap states, which is far from equilibrium even at low bias voltages. A nonequilibrium distribution is established due to an interplay between voltage-driven interlevel Landau-Zener transitions and intralevel inelastic relaxation. The Fano factor (the ratio of the zero-frequency noise to the dc current) is enhanced drastically, being proportional to the number of times which a particle flies along the Andreev trajectory before it escapes from the level due to inelastic scattering. For weak Landau-Zener transitions, the enhancement is even larger due to a smaller dc current. C1 Aalto Univ, Low Temp Lab, FIN-02015 Helsinki, Finland. LD Landau Theoret Phys Inst, Moscow 117940, Russia. Univ Oslo, Dept Phys, Ctr Adv Mat & Nanotechnol, N-0316 Oslo, Norway. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. Argonne Natl Lab, Argonne, IL 60439 USA. RP Kopnin, NB (reprint author), Aalto Univ, Low Temp Lab, PO Box 2200, FIN-02015 Helsinki, Finland. RI Galperin, Yuri/A-1851-2008 OI Galperin, Yuri/0000-0001-7281-9902 NR 23 TC 0 Z9 0 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 100504 DI 10.1103/PhysRevB.76.100504 PG 4 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300014 ER PT J AU Kramer, S Stern, R Horvatic, M Berthier, C Kimura, T Fisher, R AF Kraemer, S. Stern, R. Horvatic, M. Berthier, C. Kimura, T. Fisher, R. TI Nuclear magnetic resonance evidence for a strong modulation of the Bose-Einstein condensate in BaCuSi2O6 SO PHYSICAL REVIEW B LA English DT Article ID TLCUCL3; MAGNONS; PHASE; FIELD AB We present a Cu-63,Cu-65 and Si-29 NMR study of the quasi-2D coupled spin 1/2 dimer compound BaCuSi2O6 in the magnetic field range 13-26 T and at temperatures as low as 50 mK. NMR data in the gapped phase reveal that below 90 K different intradimer exchange couplings and different gaps (Delta(B)/Delta(A)=1.16) exist in every second plane along the c axis, in addition to a planar incommensurate (IC) modulation. Si-29 spectra in the field induced magnetic ordered phase reveal that close to the quantum critical point at H-c1=23.35 T the average boson densityn of the Bose-Einstein condensate is strongly modulated along the c axis with a density ratio for every second plane n(A)n(B)similar or equal to 5. An IC modulation of the local density is also present in each plane. C1 CNRS, Grenoble High Magnet Field Lab, F-38042 Grenoble, France. NICPB, EE-12618 Tallinn, Estonia. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Stanford Univ, Dept Appl Phys, Geballe Lab Adv Mat, Stanford, CA 94305 USA. RP Kramer, S (reprint author), CNRS, Grenoble High Magnet Field Lab, BP 166, F-38042 Grenoble, France. RI Berthier, Claude/D-9686-2011; Stern, Raivo/A-5387-2008 OI Berthier, Claude/0000-0001-6796-0506; Stern, Raivo/0000-0002-6724-9834 NR 17 TC 22 Z9 22 U1 1 U2 15 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 100406 DI 10.1103/PhysRevB.76.100406 PG 4 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300008 ER PT J AU Kruger, F Wilson, SD Shan, L Li, SL Huang, Y Wen, HH Zhang, SC Dai, PC Zaanen, J AF Kruger, F. Wilson, S. D. Shan, L. Li, Shiliang Huang, Y. Wen, H.-H. Zhang, S.-C. Dai, Pengcheng Zaanen, J. TI Magnetic fluctuations in n-type high-T-c superconductors reveal breakdown of fermiology: Experiments and Fermi-liquid/RPA calculations SO PHYSICAL REVIEW B LA English DT Article ID TRANSITION-TEMPERATURE SUPERCONDUCTOR; NEUTRON-SCATTERING; EXCITATION SPECTRUM; STRIPES; SYSTEM; ORDER AB By combining experimental measurements of the quasiparticle and dynamical magnetic properties of optimally electron-doped Pr0.88LaCe0.12CuO4 with theoretical calculations, we demonstrate that the conventional fermiology approach cannot possibly account for the magnetic fluctuations in these materials. In particular, we perform tunneling experiments on the very same sample for which a dynamical magnetic resonance has been reported recently and use photoemission data by others on a similar sample to characterize the fermionic quasiparticle excitations in great detail. We subsequently use this information to calculate the magnetic response within the conventional fermiology framework as applied in a large body of work for the hole-doped superconductors to find a profound disagreement between the theoretical expectations and the measurements: this approach predicts a steplike feature rather than a sharp resonance peak, it underestimates the intensity of the resonance by an order of magnitude, it suggests an unreasonable temperature dependence of the resonance, and most severely, it predicts that most of the spectral weight resides in incommensurate wings which are a key feature of the hole-doped cuprates but have never been observed in the electron-doped counterparts. Our findings strongly suggest that the magnetic fluctuations reflect the quantum-mechanical competition between antiferromagnetic and superconducting orders. C1 Leiden Univ, Inst Lorentz, NL-2300 RA Leiden, Netherlands. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Chinese Acad Sci, Inst Phys, Natl Lab Supercond, Beijing 100080, Peoples R China. Chinese Acad Sci, Inst Phys, Natl Lab Condensed Matter Phys, Beijing 100080, Peoples R China. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Oak Ridge Natl Lab, Neutron Scattering Sci Div, Oak Ridge, TN 37831 USA. RP Kruger, F (reprint author), Leiden Univ, Inst Lorentz, POB 9506, NL-2300 RA Leiden, Netherlands. RI Li, Shiliang/B-9379-2009; Zhang, Shou-Cheng/B-2794-2010; Dai, Pengcheng /C-9171-2012; Kruger, Frank/M-4076-2014 OI Dai, Pengcheng /0000-0002-6088-3170; Kruger, Frank/0000-0002-1009-6785 NR 44 TC 19 Z9 19 U1 0 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 9 AR 094506 DI 10.1103/PhysRevB.76.094506 PG 9 WC Physics, Condensed Matter SC Physics GA 215CO UT WOS:000249786100076 ER PT J AU Kusano, E Kawasaki, S Matano, K Zheng, GQ Meng, RL Cmaidalka, J Chu, CW AF Kusano, E. Kawasaki, S. Matano, K. Zheng, Guo-Qing Meng, R. L. Cmaidalka, J. Chu, C. W. TI Pressure dependence of the superconducting transition and electron correlations in NaxCoO2 center dot 1.3H(2)O SO PHYSICAL REVIEW B LA English DT Article ID NAXCOO2; MODEL AB We report T-c and Co-59 nuclear quadrupole resonance measurements on the cobalt oxide superconductor NaxCoO2 center dot 1.3H(2)O (T-c=4.8 K) under hydrostatic pressure (P) up to 2.36 GPa. T-c decreases with increasing pressure at an average rate of -0.49 +/- 0.09 K/GPa. At low pressures P <= 0.49 GPa, the decrease of T-c is accompanied by a weakening of the spin correlations at a finite wave vector and a reduction of the density of states (DOS) at the Fermi level. At high pressures above 1.93 GPa, however, the decrease of T-c is mainly due to a reduction of the DOS. These results indicate that the electronic and magnetic state of Co is primarily responsible for the superconductivity. The spin-lattice relaxation rate 1/T-1 at P=0.49 GPa shows a T-3 variation below T-c down to T similar to 0.12T(c), which provides compelling evidence for the presence of line nodes in the superconducting gap function. C1 Okayama Univ, Dept Phys, Okayama 700, Japan. Univ Houston, Dept Phys, TCSAM, Houston, TX 77204 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Hong Kong Univ Sci & Technol, Hong Kong, Peoples R China. RP Kusano, E (reprint author), Okayama Univ, Dept Phys, Okayama 700, Japan. RI KAWASAKI, Shinji/B-2586-2011; MATANO, Kazuaki/B-2629-2011; Zheng, Guo-qing/B-1524-2011 NR 19 TC 8 Z9 9 U1 2 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 100506 DI 10.1103/PhysRevB.76.100506 PG 4 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300016 ER PT J AU Liu, ACY Arenal, R Chen, XD AF Liu, A. C. Y. Arenal, R. Chen, Xidong TI Clustering in a highly hydrogenated diamondlike carbon determined using fluctuation electron microscopy and phenomenological atomistic simulations SO PHYSICAL REVIEW B LA English DT Article ID AMORPHOUS-CARBON; FILMS AB We compare fluctuation electron microscopy data to simulations from phenomenological atomic models and demonstrate a strong correspondence between some features in the experimental data and certain atomic configurations. This allows the nature of atomic clustering in a highly hydrogenated diamondlike carbon to be determined more closely. We compare the structural information garnered from fluctuation electron microscopy and Raman spectroscopy for a particular diamondlike carbon and find consistency between the two techniques in the region where their information overlaps. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Off Natl Etud & Rech Aerosp, CNRS, Lab Etud Microstruct, F-92322 Chatillon, France. Argonne Natl Lab, Ctr Electron Microscopy, Argonne, IL 60439 USA. Cedarville Univ, Cedarville, OH 45314 USA. RP Liu, ACY (reprint author), Argonne Natl Lab, Div Sci Mat, 9700 S Cass Ave, Argonne, IL 60439 USA. EM aliu@anl.gov RI Arenal, Raul/D-2065-2009 OI Arenal, Raul/0000-0002-2071-9093 NR 14 TC 7 Z9 7 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 12 AR 121401 DI 10.1103/PhysRevB.76.121401 PG 4 WC Physics, Condensed Matter SC Physics GA 215CS UT WOS:000249786500005 ER PT J AU Lorenz, B Wang, YQ Chu, CW AF Lorenz, Bernd Wang, Ya-Qi Chu, Ching-Wu TI Ferroelectricity in perovskite HoMnO3 and YMnO3 SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC-STRUCTURE AB Ferroelectricity is observed in orthorhombic HoMnO3 and YMnO3 at the magnetic lock-in transitions into an E-type structure or an incommensurate phase with a temperature independent wave vector, respectively. In HoMnO3, the ferroelectric polarization strongly depends on the external magnetic field, indicating the involvement of the rare earth moment order in this compound. The results are discussed within the framework of recent theoretical models, in particular, the double exchange driven polar displacements predicted for E-type magnetic structures. C1 Univ Houston, TCS, Dept Phys, Houston, TX 77204 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Hong Kong Univ Sci & Technol, Hong Kong, Peoples R China. RP Lorenz, B (reprint author), Univ Houston, TCS, Dept Phys, Houston, TX 77204 USA. NR 24 TC 134 Z9 136 U1 8 U2 47 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 J9 PHYS REV B JI Phys. Rev. B PD SEP PY 2007 VL 76 IS 10 AR 104405 DI 10.1103/PhysRevB.76.104405 PG 5 WC Physics, Condensed Matter SC Physics GA 215CQ UT WOS:000249786300050 ER EF