FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Liu, YC Xu, HY Mu, R Henderson, DO Lu, YM Zhang, JY Shen, DZ Fan, XW White, CW AF Liu, YC Xu, HY Mu, R Henderson, DO Lu, YM Zhang, JY Shen, DZ Fan, XW White, CW TI Production, structure, and optical properties of ZnO nanocrystals embedded in CaF2 matrix SO APPLIED PHYSICS LETTERS LA English DT Article ID SEQUENTIAL ION-IMPLANTATION; MOLECULAR-BEAM EPITAXY; COLOR-CENTER; THIN-FILMS; ZINC-OXIDE; PHOTOLUMINESCENCE; GROWTH; GAAS; GE; SI AB High-quality ZnO nanocrystals have been fabricated by zinc ion implantation (160 keV, 1x10(17) ions/cm(2)) into a CaF2(111) single-crystal substrate followed by thermal annealing from 300 to 700 degreesC. X-ray diffraction results show that ZnO nanocrystals in CaF2(111) substrate have a (002) preferred orientation. The average grain size is ranging from 14 to 19 nm corresponding to the annealing temperatures from 500 to 700 degreesC. A very strong ultraviolet near-band edge emission is observed from 372 to 379 nm. The emission intensity is enhanced and linewidth is narrowed as the annealing temperature increases. The commonly observed visible green emission associated with deep-level defects in ZnO is suppressed. (C) 2003 American Institute of Physics. C1 Chinese Acad Sci, Changchun Inst Opt Fine Mech & Phys, Key Lab Excited State Proc, Changchun 130021, Peoples R China. NE Normal Univ, Adv Ctr Optoelect Funct Mat Res, Changchun 130024, Peoples R China. Fisk Univ, Dept Phys, Chem Phys Lab, Nashville, TN 37028 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Liu, YC (reprint author), Chinese Acad Sci, Changchun Inst Opt Fine Mech & Phys, Key Lab Excited State Proc, 140 Renmin St, Changchun 130021, Peoples R China. RI NENU, OE Lab/B-2417-2013; Xu, Haiyang/C-2920-2014; Liu, Yichun/E-4946-2017 OI Liu, Yichun/0000-0002-8628-6112 NR 18 TC 49 Z9 51 U1 0 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 AUG 11 PY 2003 VL 83 IS 6 BP 1210 EP 1212 DI 10.1063/1.1591248 PG 3 WC Physics, Applied SC Physics GA 708QV UT WOS:000184580600051 ER PT J AU Liu, SF Corbett, JD AF Liu, SF Corbett, JD TI Synthesis, structure, and properties of the new intermetallic compounds SrPdTI2 and SrPtTI2 SO INORGANIC CHEMISTRY LA English DT Article ID ZINTL PHASE; INDIUM CLUSTER; SOLID-STATE; THALLIUM; NETWORK; BOUNDARY; GALLIUM; LA3IN5 AB The title compounds have been synthesized and characterized structurally and through property measurements and electronic structure calculations. Single-crystal X-ray diffraction analyses reveal that the two compounds crystallize in an orthorhombic system, MgCuAl2 type (Cmcm, Z = 4, a = 4.486(2), 4.491(3) Angstrom, b = 10-991(5), 10.990(6) Angstrom, c = 8.154(1), 8.140(4) Angstrom for SrPdTI2, and SrPtTI2, respectively). The structure can be directly derived from that of hexagonal SrTI2 (Caln(2) type) in which four-bonded thallium atoms in shared puckered hexagons generate tunnels. The Pd or Pt is encapsulated (with symmetry reduction) on the side of each tunnel within a distorted trigonal prism. Band structure calculations (EHTB) on both SrTI2 and SrPdTl2 demonstrate the effects of the conversion, with strong Pd-Tl bonding and appreciable electron transfer from Tl to Pd. Property measurements show that SrPdTl2 is metallic, as expected. C1 Iowa State Univ, Ames Lab, Ames, IA 50010 USA. Iowa State Univ, Dept Chem, Ames, IA 50010 USA. RP Corbett, JD (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50010 USA. EM jdc@ameslab.gov NR 30 TC 11 Z9 11 U1 0 U2 4 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 AUG 11 PY 2003 VL 42 IS 16 BP 4898 EP 4901 DI 10.1021/ic030089k PG 4 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 709MY UT WOS:000184630000019 PM 12895113 ER PT J AU Corbett, JD Leon-Escamilla, EA AF Corbett, JD Leon-Escamilla, EA TI Role of hydrogen in stabilizing new hydride phases or altering old ones SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT 8th International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2002) CY SEP 02-06, 2002 CL ANNECY, FRANCE DE Zintl phases; hydrogen impurities; interstitial atoms; synthesis and structure; fluoride vs. hydride ID ZINTL PHASE; INTERMETALLIC COMPOUNDS; CR5B3-LIKE STRUCTURES; ALKALINE-EARTH; METALS; SR; EU; BA; IMPURITIES; BINARY AB The role of hydrogen impurities in many of the more active metals in the formation of ternary compounds has often not been considered or recognized when these reactants do not contain significant metal hydride phases. This is a particular problem because most phase identifications or structure determinations have traditionally depended on X-ray diffraction means. Extended investigations have established that the alkaline-earth metals, plus some other divalent metals, have evidently often contributed substantial amounts of hydrogen. and this feature has led to numerous erroneous reports of supposed binary phases that form with the main-group (p) elements. Methods of detection and some ready means to avoid these problems will be described. The particularly serious examples that occur among phases reported with beta-Yb5Sb3, Mn5Si3, and Cr5B3-type binary structures for pnictogen (As-Bi) and tetrel (Si-Pb) elements are detailed for 32 examples. Fluoride has proven to be useful as a stand-in for hydride in a variety of these systems. (C) 2002 Elsevier B.V. All rights reserved. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Corbett, JD (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. NR 19 TC 9 Z9 9 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD AUG 11 PY 2003 VL 356 BP 59 EP 64 DI 10.1016/S0925-8388(02)01215-X PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 711DU UT WOS:000184725000014 ER PT J AU Sadoc, A Majzoub, EH Huett, VT Kelton, KF AF Sadoc, A Majzoub, EH Huett, VT Kelton, KF TI Local structure in hydrogenated Ti-Zr-Ni quasicrystals and approximants SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT 8th International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2002) CY SEP 02-06, 2002 CL ANNECY, FRANCE DE hydrogen storage materials; liquid quenching; EXAFS; synchrotron radiation; X-ray spectroscopies ID ORDER AB We have investigated the influence of hydrogen on the local structure of Ti-Zr-Ni alloys, icosahedral quasicrystals or crystalline approximants, using extended X-ray absorption fine structure (EXAFS). With an increasing hydrogen-to-metal ratio from 0 to 1.7, a general increase of all the mean first distances was found except for the Zr-Ni (Ni-Zr) ones. The perturbation of the (quasi)lattice, induced by hydrogenation, is a maximum around the Ti and Zr atoms, which suggests that hydrogen atoms sit preferentially near titanium and zirconium atoms. (C) 2002 Elsevier B.V. All rights reserved. C1 Univ Cergy Pontoise, Lab Phys Mat & Surfaces, F-95031 Cergy Pontoise, France. CEA, CNRS, Lab Utilisat Rayonnement Electromagnet, MENESR, F-91898 Orsay, France. Sandia Natl Labs, Livermore, CA 95441 USA. Washington Univ, Dept Phys, St Louis, MO 63130 USA. RP Sadoc, A (reprint author), Univ Cergy Pontoise, Lab Phys Mat & Surfaces, Neuville Oise, F-95031 Cergy Pontoise, France. NR 8 TC 15 Z9 15 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD AUG 11 PY 2003 VL 356 BP 96 EP 99 DI 10.1016/S0925-8388(02)01218-5 PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 711DU UT WOS:000184725000022 ER PT J AU Barnes, RG Chang, CT Majer, G Kaess, U AF Barnes, RG Chang, CT Majer, G Kaess, U TI Electron density-of-states and the metal-insulator transition in LaHx SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT 8th International Symposium on Metal-Hydrogen Systems, Fundamentals and Applications (MH2002) CY SEP 02-06, 2002 CL ANNECY, FRANCE DE metal-insulator transition; lanthanum hydrides : electronic structure ID STOICHIOMETRIC LANTHANUM TRIHYDRIDE; MAGNETIC-RESONANCE; SYSTEM; RESISTIVITY; DIFFUSION; HYDRIDES; MOTION AB The temperature dependence of the Gd3+ impurity ion spin relaxation rate, tau(i)(-1), in lanthanum hydrides, LaHx (2.0less than or equal toxless than or equal to3.0), probes the metal-insulator (MI) transition in this system. Because Gd3+ is an S-state ion, tau(i)(-1) depends on interaction with conduction electrons in the metallic state, resulting in Korringa-type behavior, tau(i)T=constant, and (tau(i)T)(-1/2)proportional toN(E-F), the electronic den sity-of-states at the Fermi level. In the non-metallic state, weak phonon processes result in a temperature dependence, tau(i)(-1)proportional toT(n), with 3 2Delta) is governed by their anharmonicity. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Pohang Univ Sci & Technol, Dept Phys, Natl Creat Res Initiat Ctr Supercond, Pohang 790784, South Korea. RP Demsar, J (reprint author), Los Alamos Natl Lab, MS K764, Los Alamos, NM 87545 USA. EM jdemsar@lanl.gov RI Demsar, Jure/B-5578-2008; Demsar, Jure/F-7243-2016 OI Demsar, Jure/0000-0003-4551-7444; NR 23 TC 10 Z9 11 U1 1 U2 6 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-9792 EI 1793-6578 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD AUG 10 PY 2003 VL 17 IS 18-20 BP 3675 EP 3681 DI 10.1142/S0217979203021605 PN 2 PG 7 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 727AX UT WOS:000185634800044 ER PT J AU Downward, L Bridges, F Cao, D Neumeier, J Zhou, L AF Downward, L Bridges, F Cao, D Neumeier, J Zhou, L TI Evidence for a universal relationship between magnetization and changes in the local structure SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 4th International Conference on New Theories, Discoveries and Applications of Superconductors and Related Materials CY JAN 16-21, 2003 CL SAN DIEGO, CALIFORNIA DE XAFS; La0.79Ca0.21MnO3; CMR; polaron distortion ID LA1-XCAXMNO3; DISTORTIONS; MAGNETISM AB X-ray Absorption Fine Structure (XAFS) measurements of the colossal magnetoresistance (CMR) sample La0.79Ca0.21MnO3 at high fields indicate a decrease in the width parameter of the pair distribution function, sigma, as the applied magnetic field is increased for T near T-c. The change in sigma(2) from the disordered polaron state varies approximately exponentially with magnetization irrespective of whether the sample magnetization was achieved through a change in temperature or the application of an external magnetic field. This suggests a more universal relationship between local structure and the sample magnetization than was previously indicated. C1 Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. RP Downward, L (reprint author), Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. NR 9 TC 3 Z9 3 U1 1 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD AUG 10 PY 2003 VL 17 IS 18-20 BP 3726 EP 3728 DI 10.1142/S0217979203021691 PN 2 PG 3 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 727AX UT WOS:000185634800054 ER PT J AU Hewett, DW AF Hewett, DW TI Fragmentation, merging, and internal dynamics for PIC simulation with finite size particles SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID PLASMA SIMULATION; COLLIDING PLASMAS; COLLISION MODEL; FLOW; CODE AB Components of a new type of "smart PIC" algorithm, intended to bridge the gap between Eulerian fluid regimes and kinetic regimes, are developed. Enlarging the scope of PIC, the CPK method (Complex Particle Kinetic) concept uses an ensemble of small, fluid-like macro-particles to represent particle distributions in phase space. These macroparticles are Gaussian-shaped in both position and velocity compared to the phase-space delta functions used in standard PIC and the spatial "sugar cube" particles used in an early version of this model [1]. Time evolution is modeled by a combination of the Lagrangian motion and internal evolution within each individual macro-particle. An analytic term is added to each particle's shape that represents internal evolution consistent with the collisionless, free-streaming of each macro-particle. Collision-dominated, gamma-law gas internal evolution is also developed to define the opposite limit of collisionality. Similar to our initial effort, macro-particles are aggressively fragmented in phase space to probe for emerging kinetic features and aggressively merged, for economy, if interesting features fail to materialize. With CPK, fragmentation in both position and velocity space can be accomplished without loss of significant phase space information. Fragmentation preserves the kinetic capabilities of PIC; merging dramatically shrinks the number of particles in non-kinetic or collisional regions. In collision-dominated regimes, merging naturally produces a few Lagrangian particles that act much as nodes in Free-Lagrangian hydrodynamics. The only interaction between neutral particles is through merging; no mesh-dependent pressure gradients are needed. Finally, a linked-list data structure significantly reduces time spent "sorting" nearest neighbors for potential merging-and should lead to straightforward MPP operation. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, AX Div, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, AX Div, POB 5508, Livermore, CA 94550 USA. EM hewett1@llnl.gov NR 22 TC 15 Z9 15 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 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD AUG 10 PY 2003 VL 189 IS 2 BP 390 EP 426 DI 10.1016/S0021-9991(03)00225-0 PG 37 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 713ZW UT WOS:000184888700003 ER PT J AU Evans, TM Urbatsch, TJ Lichtenstein, H Morel, JE AF Evans, TM Urbatsch, TJ Lichtenstein, H Morel, JE TI A residual Monte Carlo method for discrete thermal radiative diffusion SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID TRANSPORT AB Residual Monte Carlo methods reduce statistical error at a rate of exp(-bN), where b is a positive constant and N is the number of particle histories. Contrast this convergence rate with 1/rootN, which is the rate of statistical error reduction for conventional Monte Carlo methods. Thus, residual Monte Carlo methods hold great promise for increased efficiency relative to conventional Monte Carlo methods. Previous research has shown that the application of residual Monte Carlo methods to the solution of continuum equations, such as the radiation transport equation, is problematic for all but the simplest of cases. However, the residual method readily applies to discrete systems as long as those systems are monotone, i.e., they produce positive solutions given positive sources. We develop a residual Monte Carlo method for solving a discrete ID non-linear thermal radiative equilibrium diffusion equation, and we compare its performance with that of the discrete conventional Monte Carlo method upon which it is based. We find that the residual method provides efficiency gains of many orders of magnitude. Part of the residual gain is due to the fact that we begin each timestep with an initial guess equal to the solution from the previous timestep. Moreover, fully consistent non-linear solutions can be obtained in a reasonable amount of time because of the effective lack of statistical noise. We conclude that the residual approach has great potential and that further research into such methods should be pursued for more general discrete and continuum systems. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Evans, TM (reprint author), Los Alamos Natl Lab, CCS-4,MS D409, Los Alamos, NM 87545 USA. NR 15 TC 2 Z9 2 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 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD AUG 10 PY 2003 VL 189 IS 2 BP 539 EP 556 DI 10.1016/S0021-9991(03)00233-X PG 18 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 713ZW UT WOS:000184888700011 ER PT J AU Mitsui, T Rose, MK Fomin, E Ogletree, DF Salmeron, M AF Mitsui, T Rose, MK Fomin, E Ogletree, DF Salmeron, M TI Hydrogen adsorption and diffusion on Pd(111) SO SURFACE SCIENCE LA English DT Article DE hydrogen molecule; hydrogen atom; palladium; scanning tunneling microscopy; surface structure, morphology, roughness, and topography; surface diffusion ID SCANNING TUNNELING MICROSCOPE; PALLADIUM; SURFACES; PT(111); ATOMS; H-2 AB The adsorption, diffusion and ordering of hydrogen on Pd(1 1 1) was studied by scanning tunneling microscopy in the temperature range of 37-90 K. At low coverage isolated hydrogen atoms were observed. They formed root3 x root3-1H islands as the coverage increased. Above 1/3 monolayer (ML) coverage areas of a new phase with root3 x root3-2H structure were formed, with both structures coexisting between 1/3 and 2/3 ML. Finally a 1 x 1 structure was formed after high exposures of hydrogen above 50 K, with a coverage close to 1 ML. Atomically resolved images reveal that H binds to fcc hollow sites. (C) 2003 Elsevier B.V. All rights reserved. C1 Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Salmeron, M (reprint author), Lawrence Berkeley Lab, Div Mat Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Ogletree, D Frank/D-9833-2016 OI Ogletree, D Frank/0000-0002-8159-0182 NR 22 TC 81 Z9 84 U1 9 U2 36 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD AUG 10 PY 2003 VL 540 IS 1 BP 5 EP 11 DI 10.1016/S0039-6028(03)00822-7 PG 7 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 709GP UT WOS:000184617700005 ER PT J AU Chen, LS Lee, L Kudlow, BA Dos Santos, HG Sletvold, O Shafeghati, Y Botha, EG Garg, A Hanson, NB Martin, GM Mian, IS Kennedy, BK Oshima, J AF Chen, LS Lee, L Kudlow, BA Dos Santos, HG Sletvold, O Shafeghati, Y Botha, EG Garg, A Hanson, NB Martin, GM Mian, IS Kennedy, BK Oshima, J TI LMNA mutations in atypical Werner's syndrome SO LANCET LA English DT Article ID HUTCHINSON-GILFORD PROGERIA; ENCODING LAMIN A/C; FAMILIAL PARTIAL LIPODYSTROPHY; DREIFUSS MUSCULAR-DYSTROPHY; MISSENSE MUTATIONS; NUCLEAR-ENVELOPE; GENE-EXPRESSION; ORGANIZATION; DISEASE; PROTEIN AB Background Werner's syndrome is a progeroid syndrome caused by mutations at the WRN helicase locus. Some features of this disorder are also present in laminopathies caused by mutant LMNA encoding nuclear lamin A/C. Because of this similarity, we sequenced LMNA in individuals with atypical Werner's syndrome (wild-type WRN). Methods Of 129 index patients referred to our international registry for molecular diagnosis of Werner's syndrome, 26 (20%) had wildtype WRN coding regions and were categorised as having atypical Werner's syndrome on the basis of molecular criteria. We sequenced all exons of LMNA in these individuals. Mutations were confirmed at the mRNA level by RT-PCR sequencing. In one patient in whom an LMNA mutation was detected and fibroblasts were available, we established nuclear morphology and subnuclear localisation. Findings In four (15%) of 26 patients with atypical Werner's syndrome, we noted heterozygosity for novel missense mutations in LMNA, specifically A57P, R133L (in two people), and L140R. The mutations altered relatively conserved residues within lamin A/C. Fibroblasts from the patient with the L140R mutation had a substantially enhanced proportion of nuclei with altered morphology and mislocalised lamins. Individuals with atypical Werner's syndrome with mutations in LMNA had a more severe phenotype than did those with the disorder due to mutant WRN. Interpretation Our findings indicate that Werner's syndrome is molecularly heterogeneous, and a subset of the disorder can be judged a laminopathy. C1 Univ Washington, Dept Pathol, Seattle, WA 98195 USA. Univ Washington, Dept Genome Sci, Seattle, WA 98195 USA. Univ Washington, Dept Biochem, Seattle, WA 98195 USA. Hosp Santa Maria, Med Genet Serv, Lisbon, Portugal. Norwegian Univ Sci & Technol, St Olav Hosp, Dept Neurosci, Sect Geriatr, N-7034 Trondheim, Norway. Univ Welf Sci & Rehabil, Tehran, Iran. Emory Univ, Sch Med, Atlanta, GA USA. Univ Texas, SW Med Ctr, Dept Internal Med, Dallas, TX USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Oshima, J (reprint author), Univ Washington, Dept Pathol, Box 357470,HSB K-543,1959 NE Pacific Ave, Seattle, WA 98195 USA. NR 30 TC 243 Z9 264 U1 0 U2 8 PU LANCET LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0140-6736 J9 LANCET JI Lancet PD AUG 9 PY 2003 VL 362 IS 9382 BP 440 EP 445 DI 10.1016/S0140-6736(03)14069-X PG 6 WC Medicine, General & Internal SC General & Internal Medicine GA 709XD UT WOS:000184651100011 PM 12927431 ER PT J AU Segal, SR Carrado, KA Marshall, CL Anderson, KB AF Segal, SR Carrado, KA Marshall, CL Anderson, KB TI Catalytic decomposition of alcohols, including ethanol, for in situ H-2 generation in a fuel stream using a layered double hydroxide-derived catalyst SO APPLIED CATALYSIS A-GENERAL LA English DT Article DE catalytic decomposition; fuel stream; layered double hydroxide; hydrogen generation ID INTERNAL-COMBUSTION ENGINES; ORGANIC-COMPOUNDS; BASIC PROPERTIES; OXIDE CATALYSTS; MIXED OXIDES; HYDROGEN; HYDROTALCITE; METHANOL; OXIDATION; AL AB Addition of small amounts of H-2 to the combustion chamber of spark ignition internal combustion (IC) engines can result in increased fuel efficiency and lower emissions. Hydrogen can be generated by decomposition of alcohols, which are now present in a large fraction of automobile fuels (reformulated gasoline). In the present study, in situ production of hydrogen by catalytic decomposition of ethanol and other alcohols over Cu/Al layered double hydroxide (LDH) derived catalysts has been investigated. Reactions were performed using both neat alcohols and alcohol/fuel mixtures at temperatures of 150-400degreesC and atmospheric pressure. Catalytic dehydrogenation of the neat alcohols to H-2 and their corresponding aldehyde appears to be the major mechanism occurring in the reactions. The active catalytic phase is derived from the initial Cu/Al LDH structure during the process. The onset of H-2 formation generally occurred at 200-230 degreesC, and is related to the formation of metallic Cu species formed during in situ modification of the initial LDH. In alcohol/fuel mixtures, dehydrogenation of the alcohols also appeared to be the major mechanism. Significant irreversible catalyst deactivation occurred above 350-360 degreesC. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem Engn, Argonne, IL 60439 USA. RP Anderson, KB (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Marshall, Christopher/D-1493-2015 OI Marshall, Christopher/0000-0002-1285-7648 NR 46 TC 18 Z9 18 U1 1 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-860X J9 APPL CATAL A-GEN JI Appl. Catal. A-Gen. PD AUG 8 PY 2003 VL 248 IS 1-2 BP 33 EP 45 DI 10.1016/S0926-860X(03)00132-7 PG 13 WC Chemistry, Physical; Environmental Sciences SC Chemistry; Environmental Sciences & Ecology GA 714BA UT WOS:000184891400004 ER PT J AU Mo, H Taub, H Volkmann, UG Pino, M Ehrlich, SN Hansen, FY Lu, E Miceli, P AF Mo, H Taub, H Volkmann, UG Pino, M Ehrlich, SN Hansen, FY Lu, E Miceli, P TI A novel growth mode of alkane films on a SiO2 surface SO CHEMICAL PHYSICS LETTERS LA English DT Article ID LIQUID NORMAL-ALKANES; MONOLAYER STRUCTURE; INTERFACES; GRAPHITE; TRIACONTANE; DIFFRACTION; MOLECULES AB Synchrotron X-ray specular scattering measurements confirm microscopically a structural model recently inferred by very-high-resolution ellipsometry of a solid dotriacontane (n-C32H66 or C32) film formed by adsorption from solution onto a SiO2 surface. Sequentially, one or two layers adsorb on the SiO2 surface with the long-axis of the C32 molecules oriented parallel to the interface followed by a C32 monolayer with the long-axis perpendicular to it. Finally, preferentially oriented bulk particles nucleate having two different crystal structures. This growth model differs from that found previously for shorter alkanes deposited from the vapor phase onto solid surfaces. (C) 2003 Elsevier B.V. All rights reserved. C1 Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Univ Missouri Res Reactor, Columbia, MO 65211 USA. Pontificia Univ Catolica Chile, Fac Fis, Santiago 22, Chile. Brookhaven Natl Lab, Upton, NY 11973 USA. Tech Univ Denmark, Dept Chem, DK-2800 Lyngby, Denmark. RP Taub, H (reprint author), Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. RI Volkmann, Ulrich/H-1802-2014 NR 23 TC 38 Z9 38 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD AUG 8 PY 2003 VL 377 IS 1-2 BP 99 EP 105 DI 10.1016/S0009-2614(03)01106-0 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 710KU UT WOS:000184680000017 ER PT J AU Dreuw, A Weisman, JL Head-Gordon, M AF Dreuw, A Weisman, JL Head-Gordon, M TI Long-range charge-transfer excited states in time-dependent density functional theory require non-local exchange SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CORRECT ASYMPTOTIC-BEHAVIOR; HARTREE-FOCK; APPROXIMATION; ENERGIES; MOLECULES AB The electrostatic attraction between the separated charges in long-range excited charge-transfer states originates from the non-local Hartree-Fock exchange potential and is, thus, a non-local property. Present-day time-dependent density functional theory employing local exchange-correlation functionals does not capture this effect and therefore fails to describe charge-transfer excited states correctly. A hybrid method that is qualitatively correct is described. (C) 2003 American Institute of Physics. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Dreuw, A (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 26 TC 942 Z9 943 U1 6 U2 95 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 AUG 8 PY 2003 VL 119 IS 6 BP 2943 EP 2946 DI 10.1063/1.1590951 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 704QE UT WOS:000184350300001 ER PT J AU Ho, TS Rabitz, H Aoiz, FJ Banares, L Vazquez, SA Harding, LB AF Ho, TS Rabitz, H Aoiz, FJ Banares, L Vazquez, SA Harding, LB TI Implementation of a fast analytic ground state potential energy surface for the N(D-2)+H-2 reaction SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID AB-INITIO DATA; CONSTRUCTION; DYNAMICS AB A new implementation is presented for the potential energy surface (PES) of the 1 (2)A(") state of the N(D-2)+H-2 system based on a set of 2715 ab initio points resulting from the multireference configuration interaction (MRCI) calculations. The implementation is carried out using the reproducing Kernel Hilbert Space interpolation method. Range parameters, via bond-order-like coordinates, are properly chosen to render a sufficiently short-range three-body interaction and a regularization procedure is invoked to yield a globally smooth PES. A fast algorithm, with the help of low-order spline reproducing kernels, is implemented for the computation of the PES and, particularly, its gradients, whose fast evaluation is essential for large scale quasi-classical trajectory calculations. It is found that the new PES can be evaluated more than ten times faster than that of an existing (old) PES based on a smaller number (1141) of data points resulting from the same MRCI calculations and a similar interpolation procedure. Although there is a general good correspondence between the two surfaces, the new PES is in much better agreement with the ab initio calculations, especially in key stationary point regions including the C-2v minimum, the C-2v transition state, and the N-H-H linear barrier. Moreover, the new PES is free of spurious small scale features. Analytic gradients are made available in the new PES code to further facilitate quasiclassical trajectory calculations, which have been performed and compared with the results based on the old surface. (C) 2003 American Institute of Physics. C1 Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Univ Complutense, Dept Quim Fis, Fac Quim, E-28040 Madrid, Spain. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Ho, TS (reprint author), Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. RI Banares, Luis/B-7922-2014; Vazquez, Saulo/A-2866-2015; Aoiz, F. Javier/G-8240-2015 OI Banares, Luis/0000-0002-0777-2375; Vazquez, Saulo/0000-0002-2473-4557; Aoiz, F. Javier/0000-0001-5718-5905 NR 20 TC 51 Z9 51 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD AUG 8 PY 2003 VL 119 IS 6 BP 3063 EP 3070 DI 10.1063/1.1588632 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 704QE UT WOS:000184350300013 ER PT J AU Kaledin, AL Miller, WH AF Kaledin, AL Miller, WH TI Time averaging the semiclassical initial value representation for the calculation of vibrational energy levels. II. Application to H2CO, NH3, CH4, CH2D2 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID QUARTIC FORCE-FIELD; MANY-MODE SYSTEMS; ROVIBRATIONAL ENERGIES; DYNAMICS; ISOTOPOMERS; MOLECULES; DIAGONALIZATION; FORMALDEHYDE; SPECTROSCOPY; AMMONIA AB A method recently developed for calculating vibrational spectral densities of molecules, previously tested successfully on H2O, is applied here to several larger molecules. The method relies on use of a time averaging procedure in the conventional semiclassical (SC) initial value representation (IVR) expression for the spectral density. The convergence of the SC-IVR average over the phase space of initial conditions (of classical trajectories) is greatly enhanced by time averaging and is generally achieved with as few as 1000 trajectories per degree of freedom. Furthermore, meaningful results can be obtained with only a single trajectory propagated for a long time. (For systems with chaotic dynamics, however, the phase space average converges more slowly.) Results for vibrational energy levels of H2CO, NH3, CH4, and CH2D2 are reported and compared with quantum mechanical calculations available in the literature. The accuracy of the time-averaged SC-IVR is very encouraging, with the vibrational energy levels consistently in agreement with the quantum results to a few parts in a thousand. (C) 2003 American Institute of Physics. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Kenneth S Pitzer Ctr Theoret Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Kaledin, AL (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 31 TC 30 Z9 30 U1 0 U2 5 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 AUG 8 PY 2003 VL 119 IS 6 BP 3078 EP 3084 DI 10.1063/1.1589477 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 704QE UT WOS:000184350300015 ER PT J AU Holmes, NC Chau, R AF Holmes, NC Chau, R TI Fast time-resolved spectroscopy in shock compressed matter SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RAMAN-SCATTERING; CARBON; PHASE AB A new analytical method for optical measurements used to determine time- and spatially-resolved effects in shocked materials is described. This method is quite general and may be applied to a variety of spectroscopic techniques. We apply this method to the interpretation of time-resolved Mie scattering spectroscopy in shocked benzene, showing the effects of nucleation of nanometer-size diamond particles as a separate condensed phase in the shock-reacted material. (C) 2003 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Chau, R (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 11 TC 4 Z9 4 U1 1 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD AUG 8 PY 2003 VL 119 IS 6 BP 3316 EP 3319 DI 10.1063/1.1589744 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 704QE UT WOS:000184350300037 ER PT J AU Li, JC Wang, Y Dong, SL Zhang, P Kolesnikov, AI AF Li, JC Wang, Y Dong, SL Zhang, P Kolesnikov, AI TI Defect hydrogen vibrations in various phases deuterium ice SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID INCOHERENT NEUTRON-SCATTERING; 2 KINDS; IH; PRESSURE; SPECTRA; D2O; IX AB The inelastic incoherent neutron scattering spectra of D2O mixed with a small amount of H2O (5% by weight) high density amorphous (hda) ice, ice-VIII, and ice-II have been measured on HET spectrometer at Rutherford Appleton Laboratory (UK). The hydrogen atom in D2O ice lattice has three distinguished vibrations: two modes normal to the O---H bond at lower frequency and a stretching mode along the O-H bond at higher frequency. For different ice phases these frequencies are different, it was found that the lower defect mode is at similar to97 meV for ice-II, at about 95 meV for hda-ice and ice-VIII, and they are all lower than the value of 105 meV for ice-Ih. The O-H stretching modes are at 415 meV for ice-II, at 418 meV for hda-ice, and at 425 meV for ice-VIII, which all are much larger than the value for ice-Ih, 406 meV. It was also found that O-D stretching modes in D2O ice-VIII is centered at similar to320 meV which is significantly higher than the corresponding value of similar to305 meV for ice-Ih. (C) 2003 American Institute of Physics. C1 UMIST, Dept Phys, Manchester M60 1QD, Lancs, England. Ocean Univ Qingdao, Dept Phys, Qingdao 266003, Peoples R China. Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. RP Li, JC (reprint author), UMIST, Dept Phys, POB 88, Manchester M60 1QD, Lancs, England. RI Kolesnikov, Alexander/I-9015-2012 OI Kolesnikov, Alexander/0000-0003-1940-4649 NR 18 TC 1 Z9 1 U1 0 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD AUG 8 PY 2003 VL 119 IS 6 BP 3332 EP 3335 DI 10.1063/1.1589748 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 704QE UT WOS:000184350300039 ER PT J AU Laskin, J Futrell, JH AF Laskin, J Futrell, JH TI Energy transfer in collisions of peptide ions with surfaces SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ASSEMBLED MONOLAYER SURFACES; RESONANCE MASS-SPECTROMETRY; FT-ICR MS; INDUCED DISSOCIATION; POLYATOMIC IONS; MOLECULAR-IONS; ORGANIC MONOLAYERS; LIQUID SURFACE; FRAGMENTATION; ENERGETICS AB Time- and energy-resolved surface induced dissociation (SID) of a singly protonated octapeptide des-Arg1-bradykinin was used to study the effect of physical properties of the SID target on the efficiency of translational to vibrational energy transfer (T-->V) in collisions of peptide ions with surfaces. Four SID targets of varying chemical composition and stiffness were examined in this work: self-assembled monolayers of 1-dodecane thiol (HSAM) and its fluorinated analog (CF3(CF2)(9)C2H4SH - FSAM) on gold, a 300 nm thick layer of lithium fluoride (LiF) on a polished titanium surface, and a 2 mum carbon vapor deposited diamond layer on a titanium surface. A RRKM-based modeling approach was utilized to extract internal energy distributions deposited into the precursor ion upon collisions with different surfaces. We found that the percent of T-->V transfer increases in the order: HSAM (10.1%), LiF (12.0%), diamond (19.2%), FSAM (20.5%). Furthermore, the width of the energy deposition function (EDF) is affected by the properties of the SID target. Collisions of peptide ions with the HSAM surface results in deposition of relatively narrow internal energy distributions with the width of the EDF increasing in the order: HSAMJ/psipi(0) decays using e(+)e(-) annihilation data collected with the BABAR detector at the Y(4S) resonance during the years 1999-2002 at the PEP-II asymmetric-energy B Factory at SLAC. Using approximately 88x10(6) B (B) over bar pairs, our results for the coefficients of the cosine and sine terms of the CP asymmetry are C-J/psipi(0)=0.38+/-0.41(stat)+/-0.09(syst) and S-J/psipi(0)=0.05+/-0.49(stat)+/-0.16(syst). C1 Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France. Univ Bari, Dipartmento Fis, I-70126 Bari, Italy. Ist Nazl Fis Nucl, I-70126 Bari, Italy. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Bergen, Dept Phys, N-5007 Bergen, Norway. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Ruhr Univ Bochum, Inst Expt Phys 1, D-44780 Bochum, Germany. Univ Bristol, Bristol BS8 1TL, Avon, England. Univ British Columbia, Vancouver, BC V6T 1Z1, Canada. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. CALTECH, Pasadena, CA 91125 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Colorado, Boulder, CO 80309 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Tech Univ Dresden, Inst Kern & Teilchenphys, D-01062 Dresden, Germany. Ecole Polytech, LLR, F-91128 Palaiseau, France. Univ Edinburgh, Edinburgh EH9 3JZ, Midlothian, Scotland. Univ Ferrara, Dipartmento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, I-44100 Ferrara, Italy. Florida A&M Univ, Tallahassee, FL 32307 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy. Ist Nazl Fis Nucl, I-16146 Genoa, Italy. Harvard Univ, Cambridge, MA 02138 USA. Univ Iowa, Iowa City, IA 52242 USA. Iowa State Univ, Ames, IA 50011 USA. Lab Accelerateur Lineaire, F-91898 Orsay, France. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. Univ London, Imperial Coll, London SW7 2BW, England. Univ London, Queen Mary, London E1 4NS, England. Univ London Royal Holloway & Bedford New Coll, Egham TW20 0EX, Surrey, England. Univ Louisville, Louisville, KY 40292 USA. Univ Manchester, Manchester M13 9PL, Lancs, England. Univ Maryland, College Pk, MD 20742 USA. Univ Massachusetts, Amherst, MA 01003 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. McGill Univ, Montreal, PQ H3A 2T8, Canada. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Ist Nazl Fis Nucl, I-20133 Milan, Italy. Univ Mississippi, University, MS 38677 USA. Univ Montreal, Lab Rene JA Levesque, Montreal, PQ H3C 3J7, Canada. Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Naples Federico II, Dipartimento Sci Fis, I-80126 Naples, Italy. Ist Nazl Fis Nucl, I-80126 Naples, Italy. Natl Inst Nucl & High Energy Phys, NIKHEF, NL-1009 DB Amsterdam, Netherlands. Univ Notre Dame, Notre Dame, IN 46556 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Padua, Dipartimento Fis, I-35131 Padua, Italy. Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Paris 06, F-75252 Paris, France. Univ Paris 07, Lab Phys Nucl HE, F-75252 Paris, France. Univ Pavia, Dipartimento Elettron, I-27100 Pavia, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Penn, Philadelphia, PA 19104 USA. Ist Nazl Fis Nucl, I-56010 Pisa, Italy. Univ Pisa, Dipartimento Fis, Scuola Normale Super, I-56010 Pisa, Italy. Prairie View A&M Univ, Prairie View, TX 77446 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Univ Rostock, D-18051 Rostock, Germany. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CEA Saclay, DAPNIA, F-91191 Gif Sur Yvette, France. Univ S Carolina, Columbia, SC 29208 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Stanford, CA 94305 USA. SUNY Albany, Albany, NY 12222 USA. Univ Tennessee, Knoxville, TN 37996 USA. Univ Texas, Austin, TX 78712 USA. Univ Texas, Richardson, TX 75083 USA. Univ Turin, Dipartimento Fis Sperimentale, I-10125 Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Trieste, Dipartmento Fis, I-34127 Trieste, Italy. Ist Nazl Fis Nucl, I-34127 Trieste, Italy. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Victoria, Victoria, BC V8W 3P6, Canada. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. Univ Perugia, I-06100 Perugia, Italy. Univ Basilicata, I-85100 Potenza, Italy. Univ Valencia, CSIC, Inst Fis Corpuscular, IFIC, Valencia, Spain. RP Aubert, B (reprint author), Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France. RI Martinez Vidal, F*/L-7563-2014; Kolomensky, Yury/I-3510-2015; Lo Vetere, Maurizio/J-5049-2012; Grancagnolo, Sergio/J-3957-2015; Lusiani, Alberto/N-2976-2015; Lusiani, Alberto/A-3329-2016; Morandin, Mauro/A-3308-2016; Della Ricca, Giuseppe/B-6826-2013; Calcaterra, Alessandro/P-5260-2015; Frey, Raymond/E-2830-2016; Peters, Klaus/C-2728-2008; Lista, Luca/C-5719-2008; Bellini, Fabio/D-1055-2009; Neri, Nicola/G-3991-2012; Forti, Francesco/H-3035-2011; Rotondo, Marcello/I-6043-2012; de Sangro, Riccardo/J-2901-2012; Sarti, Alessio/I-2833-2012; Cavallo, Nicola/F-8913-2012; Patrignani, Claudia/C-5223-2009; Monge, Maria Roberta/G-9127-2012; Kravchenko, Evgeniy/F-5457-2015; Mir, Lluisa-Maria/G-7212-2015 OI Martinez Vidal, F*/0000-0001-6841-6035; Kolomensky, Yury/0000-0001-8496-9975; Lo Vetere, Maurizio/0000-0002-6520-4480; Grancagnolo, Sergio/0000-0001-8490-8304; Lusiani, Alberto/0000-0002-6876-3288; Lusiani, Alberto/0000-0002-6876-3288; Morandin, Mauro/0000-0003-4708-4240; Della Ricca, Giuseppe/0000-0003-2831-6982; Calcaterra, Alessandro/0000-0003-2670-4826; Frey, Raymond/0000-0003-0341-2636; Peters, Klaus/0000-0001-7133-0662; Bellini, Fabio/0000-0002-2936-660X; Neri, Nicola/0000-0002-6106-3756; Forti, Francesco/0000-0001-6535-7965; Rotondo, Marcello/0000-0001-5704-6163; de Sangro, Riccardo/0000-0002-3808-5455; Sarti, Alessio/0000-0001-5419-7951; Patrignani, Claudia/0000-0002-5882-1747; Monge, Maria Roberta/0000-0003-1633-3195; Mir, Lluisa-Maria/0000-0002-4276-715X NR 15 TC 0 Z9 0 U1 0 U2 3 PU AMERICAN 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 AUG 8 PY 2003 VL 91 IS 6 AR 061802 DI 10.1103/PhysRevLett.91.061802 PG 7 WC Physics, Multidisciplinary SC Physics GA 710JZ UT WOS:000184678200012 ER PT J AU Bonev, SA Gygi, F Ogitsu, T Galli, G AF Bonev, SA Gygi, F Ogitsu, T Galli, G TI High-pressure molecular phases of solid carbon dioxide SO PHYSICAL REVIEW LETTERS LA English DT Article ID CRYSTAL-STRUCTURE; CO2; TEMPERATURES; STISHOVITE; TRANSITION; SIO2; GPA; SPECTROSCOPY; COMPRESSION; QUARTZ AB We present a theoretical study of solid CO2 up to 50 GPa and 1500 K using first-principles calculations. In this pressure-temperature range, interpretations of recent experiments have suggested the existence of CO2 phases which are intermediate between molecular and covalent-bonded solids. We reexamine the concept of intermediate phases in the CO2 phase diagram and propose instead molecular structures, which provide an excellent agreement with measurements. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Bonev, SA (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 32 TC 52 Z9 52 U1 1 U2 15 PU AMERICAN 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 AUG 8 PY 2003 VL 91 IS 6 AR 065501 DI 10.1103/PhysRevLett.91.065501 PG 4 WC Physics, Multidisciplinary SC Physics GA 710JZ UT WOS:000184678200028 PM 12935085 ER PT J AU Gurvitz, SA Fedichkin, L Mozyrsky, D Berman, GP AF Gurvitz, SA Fedichkin, L Mozyrsky, D Berman, GP TI Relaxation and the Zeno effect in qubit measurements SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUANTUM TRANSPORT; RATE-EQUATIONS; SYSTEM; DECAY AB We consider a qubit interacting with its environment and continuously monitored by a detector represented by a point contact. Bloch-type equations describing the entire system of the qubit, the environment, and the detector are derived. Using these equations we evaluate the detector current and its noise spectrum in terms of the decoherence and relaxation rates of the qubit. Simple expressions are obtained that show how these quantities can be accurately measured. We demonstrate that due to interaction with the environment, the measurement can never localize a qubit even for infinite decoherence rate. C1 Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Clarkson Univ, Dept Phys, Potsdam, NY 13699 USA. RP Gurvitz, SA (reprint author), Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. NR 20 TC 62 Z9 65 U1 0 U2 2 PU AMERICAN 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 AUG 8 PY 2003 VL 91 IS 6 AR 066801 DI 10.1103/PhysRevLett.91.066801 PG 4 WC Physics, Multidisciplinary SC Physics GA 710JZ UT WOS:000184678200042 PM 12935099 ER PT J AU Mielke, SL Peterson, KA Schwenke, DW Garrett, BC Truhlar, DG Michael, JV Su, MC Sutherland, JW AF Mielke, SL Peterson, KA Schwenke, DW Garrett, BC Truhlar, DG Michael, JV Su, MC Sutherland, JW TI H+H-2 thermal reaction: A convergence of theory and experiment SO PHYSICAL REVIEW LETTERS LA English DT Article ID POTENTIAL-ENERGY SURFACE; SHOCK TUBE TECHNIQUE; RATE CONSTANTS; TEMPERATURE-RANGE; CHEMICAL-KINETICS; HYDROGEN MOLECULE; ESR DETECTION; GROUND-STATE; H-3; PHOTOLYSIS AB New experimental and theoretical rate constants for two isotopologs of the simplest chemical reaction, H+H-2-->H-2+H, are presented. The theoretical results are obtained using accurate quantum dynamics with a converged Born-Oppenheimer potential energy surface and include non-Born-Oppenheimer corrections. The new experiments are carried out using a shock tube and complement earlier investigations over a very large T range, 167 to 2112 K. Experiment and theory now agree perfectly, within experimental error, bringing this 75-year-old scientific problem to completion. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Washington State Univ, Dept Chem, Pullman, WA 99164 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Mielke, SL (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Michael, Joe/E-3907-2010; Garrett, Bruce/F-8516-2011; Mielke, Steven/B-7533-2008; schwenke, david/I-3564-2013; Truhlar, Donald/G-7076-2015 OI Mielke, Steven/0000-0002-1938-7503; Truhlar, Donald/0000-0002-7742-7294 NR 53 TC 94 Z9 96 U1 2 U2 23 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 AUG 8 PY 2003 VL 91 IS 6 AR 063201 DI 10.1103/PhysRevLett.91.063201 PG 4 WC Physics, Multidisciplinary SC Physics GA 710JZ UT WOS:000184678200015 PM 12935072 ER PT J AU Schafer, J Sing, M Claessen, R Rotenberg, E Zhou, XJ Thorne, RE Kevan, SD AF Schafer, J Sing, M Claessen, R Rotenberg, E Zhou, XJ Thorne, RE Kevan, SD TI Unusual spectral behavior of charge-density waves with imperfect nesting in a quasi-one-dimensional metal SO PHYSICAL REVIEW LETTERS LA English DT Article ID SURFACE-STATE; NBSE3; PHOTOEMISSION; ENERGY AB Low-temperature electronic properties of the charge-density-wave system NbSe3 are reported from angle-resolved photoemission at 15 K. The effect of two instabilities q(1) and q(2) on the k-resolved spectral function is observed for the first time. With a pseudogap background, the gap spectra exhibit maxima at Delta(1)(*)similar to110 meV and Delta(2)(*)similar to45 meV. Imperfectly nested sections of the Fermi surface lack a Fermi-Dirac edge, and show the signature of a dispersion that is modified by self-energy effects. The energy scale is of the order of the effective gap 2Delta(2)(*). The effect disappears above T-2, suggesting a correlation with the charge-density-wave state. C1 Univ Augsburg, Inst Expt Phys, D-86135 Augsburg, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Cornell Univ, Atom & Solid State Phys Lab, Ithaca, NY 14853 USA. Univ Oregon, Dept Phys, Eugene, OR 97403 USA. RP Schafer, J (reprint author), Univ Augsburg, Inst Expt Phys, D-86135 Augsburg, Germany. RI Rotenberg, Eli/B-3700-2009; Kevan, Stephen/F-6415-2010; Claessen, Ralph/A-2045-2017 OI Rotenberg, Eli/0000-0002-3979-8844; Kevan, Stephen/0000-0002-4621-9142; Claessen, Ralph/0000-0003-3682-6325 NR 21 TC 44 Z9 44 U1 0 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD AUG 8 PY 2003 VL 91 IS 6 AR 066401 DI 10.1103/PhysRevLett.91.066401 PG 4 WC Physics, Multidisciplinary SC Physics GA 710JZ UT WOS:000184678200032 PM 12935089 ER PT J AU Uno, I Carmichael, GR Streets, DG Tang, Y Yienger, JJ Satake, S Wang, Z Woo, JH Guttikunda, S Uematsu, M Matsumoto, K Tanimoto, H Yoshioka, K Iida, T AF Uno, I Carmichael, GR Streets, DG Tang, Y Yienger, JJ Satake, S Wang, Z Woo, JH Guttikunda, S Uematsu, M Matsumoto, K Tanimoto, H Yoshioka, K Iida, T TI Regional chemical weather forecasting system CFORS: Model descriptions and analysis of surface observations at Japanese island stations during the ACE-Asia experiment SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE chemical transport model; dust; aerosol; ACE-Asia; observation; aerosol optical thickness ID TRANSPORT MODELS; DUST CYCLE; EAST-ASIA; AEROSOL; DISTRIBUTIONS; SIMULATION; ATMOSPHERE; DEPOSITION; SCHEME; RAMS AB [1] The Chemical Weather Forecast System (CFORS) is designed to aid in the design of field experiments and in the interpretation/postanalysis of observed data. The system integrates a regional chemical transport model with a multitracer, online system built within the Regional Atmospheric Modeling System ( RAMS)mesoscale model. CFORS was deployed in forecast and postanalysis modes during the NASA Global Tropospheric Experiment(GTE)-Transport and Chemical Evolution over the Pacific (TRACE-P), International Global Atmospheric Chemistry project (IGAC)-International Geosphere-Biosphere Programme (IGBP) Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia), and National Oceanic and Atmospheric Administration Intercontinental Transport and Chemical Transformation of Anthropogenic Pollution 2002 (ITCT 2K2) field studies. A description of the CFORS model system is presented. The model is used to help interpret the Variability of Maritime Aerosol Properties (VMAP) surface observation data. The CFORS model results help to explain the time variation of both anthropogenic pollutants ( sulfate, black carbon, and CO) and natural constituents including radon and mineral dust. Time series and time-height cross-section analysis of gases and aerosols are presented to help identify key processes. Synoptic-scale weather changes are found to play an important role in the continental-scale transport of pollution in the springtime in East Asia. The complex vertical and horizontal structure of pollutants in these outflow events is also presented and discussed. C1 Kyushu Univ, Appl Mech Res Inst, Fukuoka 8168580, Japan. Frontier Res Syst Global Change, IGAC Yokohama, Kanazawa Ku, Yokohama, Kanagawa 2360001, Japan. Univ Iowa, Ctr Global & Reg Environm Res, Iowa City, IA 52242 USA. Argonne Natl Lab, Argonne, IL 60439 USA. US Off, ICEI US, Cities Climate Protect Campaign, Berkeley, CA USA. Univ Tokyo, Ocean Res Inst, Nakano Ku, Tokyo 1648639, Japan. Natl Inst Environm Studies, Div Atmospher Environm, Tsukuba, Ibaraki 3058506, Japan. Shimane Prefectural Inst Publ Hlth & Environm Sci, Matsue, Shimane 6900122, Japan. Nagoya Univ, Grad Sch Engn, Chkusa Ku, Nagoya, Aichi 4648603, Japan. RP Kyushu Univ, Appl Mech Res Inst, Kasuga Pk 6-1, Fukuoka 8168580, Japan. EM iuno@riam.kyushu-u.ac.jp; gcarmich@icaen.uiowa.edu; dstreets@anl.gov; ytang@cgrer.uiowa.edu; jyienger@iclei.org; satake@riam.kyushu-u.ac.jp; zifawang@jamstec.go.jp; woojh21@cgrer.uiowa.edu; sguttiku@cgrer.uiowa.edu; uematsu@ori.u-tokyo.ac.jp; kiyoshi@ori.u-tokyo.ac.jp; tanimoto@nies.go.jp; yoshioka-katsuhiro@pref.shimane.jp; t-iida@nucl.nagoya-u.ac.jp RI Uno, Itsushi/B-5952-2011; Takemura, Toshihiko/C-2822-2009; Kyushu, RIAM/F-4018-2015; U-ID, Kyushu/C-5291-2016; Wang, Zifa/B-5192-2008; Wang, Zifa/B-5799-2011; Tanimoto, Hiroshi/E-6779-2010; Tang, Youhua/D-5205-2016 OI Takemura, Toshihiko/0000-0002-2859-6067; Tanimoto, Hiroshi/0000-0002-5424-9923; Tang, Youhua/0000-0001-7089-7915 NR 43 TC 168 Z9 175 U1 7 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD AUG 7 PY 2003 VL 108 IS D23 AR 8668 DI 10.1029/2002JD002845 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 713EG UT WOS:000184843500001 ER PT J AU Gianotto, AK Hodges, BDM Benson, MT Harrington, PD Appelhans, AD Olson, JE Groenewold, GS AF Gianotto, AK Hodges, BDM Benson, MT Harrington, PD Appelhans, AD Olson, JE Groenewold, GS TI Ion-molecule reactions of gas-phase chromium oxyanions: CrxOyHz-+H2O SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID MICROPROBE MASS-SPECTROMETRY; TRANSITION-METAL OXIDE; ALKALINE-EARTH CHROMATE; CLUSTER IONS; LASER ABLATION/IONIZATION; ELECTRONIC-STRUCTURE; SPECIATION ANALYSIS; SODIUM-NITRATE; TRAP; COMPLEXES AB Chromium oxyanions having the general formula CrxOyHz- play a key role in many industrial, environmental, and analytical processes, which motivated investigations of their intrinsic reactivity. Reactions with water are perhaps the most significant, and were studied by generating CrxOyHz- in the gas phase using a quadrupole ion trap secondary ion mass spectrometer. Of the ions in the Cr1OyHz envelope (y = 2, 3, 4; z = 0, 1), only CrO2- was observed to react with H2O, producing the hydrated CrO3H2- at a slow rate (similar to0.07% of the ion-molecule collision constant at 310 K). CrO3-, CrO4-, and CrO4H- were unreactive. In contrast, Cr2O4-, Cr2O5-, and Cr2O5H2- displayed a considerable tendency to react with H2O. Cr2O4- underwent sequential reactions with H2O, initially producing Cr2O5H2- at a rate that was similar to7% efficient. Cr2O5H2- then reacted with a second H2O by addition to form Cr2O6H4- (1.8% efficient) and by OH abstraction to form Cr2O6H3- (0.6% efficient). The reactions of Cr2O5- were similar to those of Cr2O5H2-: Cr2O5- underwent addition to form Cr2O6H2- (3% efficient) and OH abstraction to form Cr2O6H- (<1% efficient). By comparison, Cr2O6- was unreactive with H2O, and in fact, no further H2O addition could be observed for any of the Cr2O6Hz- anions. Hartree-Fock ab initio calculations showed that reactive CrxOyHz- species underwent nucleophilic attack by the incoming H20 molecules, which produced an initially formed adduct in which the water 0 was bound to a Cr center. The experimental and computational studies suggested that Cr2OyHz- species that have bi- or tricoordinated Cr centers are susceptible to attack by H20; however, when the metal becomes tetracoordinate, reactivity stops. For the Cr2OyHz- anions the lowest energy structures all contained rhombic Cr2O2 rings with pendant O atoms and/or OH groups. The initially formed [Cr2Oy- + H2O] adducts underwent H rearrangement to a gem O atom to produce stable dihydroxy structures. The calculations indicated that rearrangement did not occur in the [Cr2O5H2- + H2O] adduct, possibly because the rearranged product could not accommodate the negative charge. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Groenewold, GS (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RI Benson, Michael/B-8855-2017; OI Benson, Michael/0000-0003-4927-614X; Harrington, Peter/0000-0003-0268-8630 NR 77 TC 16 Z9 16 U1 1 U2 10 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 AUG 7 PY 2003 VL 107 IS 31 BP 5948 EP 5955 DI 10.1021/jp027083l PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 708DE UT WOS:000184551200009 ER PT J AU Tam, CN Cowan, JA Schultz, AJ Young, VG Trouw, FR Sykes, AG AF Tam, CN Cowan, JA Schultz, AJ Young, VG Trouw, FR Sykes, AG TI Neutron and X-ray diffraction, inelastic neutron scattering, and solid-state C-13 NMR investigations of polymorphic-p-chlorophenylformamide: Absence of proton transfer along the intermolecular N-H center dot center dot center dot O hydrogen bond SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID CRYSTAL-STRUCTURE; ACETANILIDE; SPECTROSCOPY; FORMAMIDES; MECHANISM; SOLITONS AB Neutron and X-ray crystal structures of p-chlorophenylformamide (ClC6H4NHCHO, 1) have been determined after recrystallization from methanol and acetone solvents. Acetone and methanol grown samples are polymorphic, where the central layer of a three layer asymmetric unit is partially (0.37:0.63) reversed within the acetone grown crystal. All structures reveal that the formamide group is essentially coplanar with the chlorophenyl ring. The possibility of hydrogen atom transfer between amide and iminol tautomers has been ruled out on the basis of crystallographic results and additional C-13 CPMAS NMR and inelastic neutron scattering investigations. Only infinite chains of hydrogen-bonded formamide units are found in the crystal. Compound 1 crystallizes from methanol in the orthorhombic space group P2(1)2(1)2(1) (Mo Kalpha radiation; 173 K; Z = 4; a = 6.1356(2) Angstrom, b = 9.5362(3) Angstrom, c = 11.8990(4) Angstrom; V = 696.2 Angstrom(3)) and (neutron radiation; 20 K; Z = 4. a = 6.0873(10) Angstrom, b = 9.5095(15) Angstrom, c = 11.814(5) Angstrom; V = 683.9 Angstrom(3)). From acetone, a supercell is observed for crystalline 1, where 3a = c (P2(1)2(1)2(1); Mo Kalpha radiation; 173 K; Z = 12; a = 9.5704(2) Angstrom, b = 11.9479(1) Angstrom, c = 18.4555(2) Angstrom; V = 2110.3 Angstrom(3)). C1 Univ S Dakota, Dept Chem, Vermillion, SD 57069 USA. Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Sykes, AG (reprint author), Univ S Dakota, Dept Chem, Vermillion, SD 57069 USA. NR 28 TC 10 Z9 10 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD AUG 7 PY 2003 VL 107 IS 31 BP 7601 EP 7606 DI 10.1021/jp034271i PG 6 WC Chemistry, Physical SC Chemistry GA 708DF UT WOS:000184551300015 ER PT J AU Doshi, DA Gibaud, A Liu, NG Sturmayr, D Malanoski, AP Dunphy, DR Chen, HJ Narayanan, S MacPhee, A Wang, J Reed, ST Hurd, AJ van Swol, F Brinker, CJ AF Doshi, DA Gibaud, A Liu, NG Sturmayr, D Malanoski, AP Dunphy, DR Chen, HJ Narayanan, S MacPhee, A Wang, J Reed, ST Hurd, AJ van Swol, F Brinker, CJ TI In-situ X-ray scattering study of continuous silica-surfactant self-assembly during steady-state dip coating SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID THIN-FILMS; MESOPOROUS SILICA; MESOSTRUCTURED MATERIALS; PORE STRUCTURES; LAMELLAR; NANOSTRUCTURES; MECHANISM AB Inorganic mesoporous thin-films are important for applications such as membranes, sensors, low-dielectric-constant insulators (so-called low kappa dielectrics), and fluidic devices. Over the past five years, several research groups have demonstrated the efficacy of using evaporation accompanying conventional coating operations such as spin- and dip-coating as an efficient means of driving the self-assembly of homogeneous solutions into highly ordered, oriented, mesostructured films. Understanding such evaporation-induced self-assembly (EISA) processes is of interest for both fundamental and technological reasons. Here, we use spatially resolved 2D grazing incidence X-ray scattering in combination with optical interferometry during steady-state dip-coating of surfactant-templated silica thin-films to structurally and compositionally characterize the EISA process. We report the evolution of a hexagonal (p6 mm) thin-film mesophase from a homogeneous precursor solution and its further structural development during drying and calcination. Monte Carlo simulations of water/ethanol/surfactant bulk phase behavior are used to investigate the role of ethanol in the self-assembly process, and we propose a mechanism to explain the observed dilation in unit cell dimensions during solvent evaporation. C1 Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. Univ New Mexico, Ctr Microengn Mat, Albuquerque, NM 87131 USA. Univ Maine, Fac Sci, UMR 6087, CNRS 72085, Le Mans 09, France. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Vienna Tech Univ, Inst Mat Chem, Vienna, Austria. RP Brinker, CJ (reprint author), Adv Mat Lab, 1001 Univ SE, Albuquerque, NM 87106 USA. RI Malanoski, Anthony/C-7814-2011 OI Malanoski, Anthony/0000-0001-6192-888X NR 37 TC 44 Z9 44 U1 1 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD AUG 7 PY 2003 VL 107 IS 31 BP 7683 EP 7688 DI 10.1021/jp027214i PG 6 WC Chemistry, Physical SC Chemistry GA 708DF UT WOS:000184551300025 ER PT J AU Benkstein, KD Kopidakis, N van de Lagemaat, J Frank, AJ AF Benkstein, KD Kopidakis, N van de Lagemaat, J Frank, AJ TI Influence of the percolation network geometry on electron transport in dye-sensitized titanium dioxide solar cells SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MODULATED PHOTOCURRENT SPECTROSCOPY; COLLOIDAL TIO2 FILMS; POTENTIAL DISTRIBUTION; AMBIPOLAR DIFFUSION; CHARGE-TRANSPORT; NANOPOROUS TIO2; POROUS TIO2; CONDUCTIVITY; EFFICIENCY; ANATASE AB Percolation theory is applied to understand the influence of network geometry on the electron transport dynamics in dye-sensitized nanocrystalline TiO2 solar cells, and the predicted results are compared with those measured by transient photocurrent. The porosity of the films was varied experimentally from 52 to 71%. Electron transport was modeled using simulated mesoporous TiO2 films, consisting of a random nanoparticle network, and the random-walk approach. The electron transport pathway through the network was correlated with the film porosity and the coordination numbers of the particles in the film. The experimental measurements and random-walk simulations were in quantitative agreement with percolation theory, which predicts a power-law dependence of the electron diffusion coefficient D on the film porosity as described by the relation: D proportional to \P - P-c\(u). The critical porosity P-c (percolation threshold) and the conductivity exponent mu were found to be 0.76 +/- 0.01 and 0.82 +/- 0.05, respectively. The fractal dimension of the nanoparticle films was estimated from the simulations to be 2.28, which is in quantitative agreement with gas-sorption measurements. It is shown that as the porosity increases, the distribution of the coordination numbers of the particles shifts from an emphasis on high coordination numbers to low ones, causing the electron transport pathway to become more tortuous and electron transport to slow. Another consequence of increasing the porosity is that the fraction of terminating particles (dead ends) in the TiO2 film increases markedly, from less than 1% for a 50% porous film to 3 1% for a 75% porous film. It is estimated that during their respective transit through 50 and 75% porous 10-mum thick films, the average number of particles visited by electrons increases by 10-fold, from 10(6) to 10(7). This study provides the first clear evidence that network topology has a strong influence on the electron transport dynamics in mesoporous TiO2 films. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Frank, AJ (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI van de Lagemaat, Jao/J-9431-2012; Kopidakis, Nikos/N-4777-2015 NR 43 TC 382 Z9 393 U1 5 U2 100 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD AUG 7 PY 2003 VL 107 IS 31 BP 7759 EP 7767 DI 10.1021/jp0226811 PG 9 WC Chemistry, Physical SC Chemistry GA 708DF UT WOS:000184551300035 ER PT J AU Haranczyk, M Bachorz, R Rak, J Gutowski, M Radisic, D Stokes, ST Nilles, JM Bowen, KH AF Haranczyk, M Bachorz, R Rak, J Gutowski, M Radisic, D Stokes, ST Nilles, JM Bowen, KH TI Excess electron attachment induces barrier-free proton transfer in binary complexes of uracil with H2Se and H2S but not with H2O SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID AB-INITIO CALCULATIONS; DENSITY-FUNCTIONAL THEORY; MOLECULAR-ORBITAL METHODS; GAUSSIAN-TYPE BASIS; GAS-PHASE; PHOTOELECTRON-SPECTROSCOPY; ORGANIC-MOLECULES; BASE-PAIRS; WATER; TAUTOMERS AB The photoelectron spectrum of the uracil-H2S anionic complex (UH2S)(-) has been recorded with 2.540 eV photons. Unlike the (uracil-H2O)(-) spectrum, which displays a broad feature with maximum at about 0.9 eV, the (UH2S)(-) spectrum reveals a broad feature with a maximum between 1.7 and 2.1 eV. The latter vertical detachment energy value is too large to be attributed to an (UH2S)(-) complex in which an intact uracil anion is solvated by H2S. The effects of electron attachment to the UH(2)A complexes (A = Se, S, O) have been studied at the density functional theory level with the B3LYP and MPW1K exchange correlation functionals as well as at the second-order Moller-Plesset perturbation theory level. The three acids cover a broad range of acidity with calculated gas-phase deprotonation enthalpies being equal to 14.8, 15.1, and 16.9 eV for H2Se. H2S, and H2O, respectively. In the case of H2Se and H2S, electron attachment is predicted to induce a barrier-free proton transfer (BFPT) from the acid to the O8 atom of uracil, with the product being the radical of hydrogenated uracil bound to AH(-). No BFPT is predicted for the anion of uracil with H2O. Critical factors for the occurrence of BFPT have been analyzed, and the role of the stabilizing interaction between the hydrogenated uracil and the deprotonated acid has been discussed. Four structures have been considered for every UH(2)A complex, and their relative stabilities are different for the neutral and anionic species. The increased stabilities of anionic complexes that undergo BFPT can be related to the properties of the second hydrogen bond (C5H...A or N1(3)H...A). In comparison with the case of neutral structures, this bond is weakened for anionic structures without BFPT and strengthened for those with BFPT. C1 Pacific NW Natl Lab, Div Chem Sci, Richland, WA 99352 USA. Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. Adam Mickiewicz Univ, Dept Chem, Quantum Chem Grp, Poznan, Poland. Johns Hopkins Univ, Dept Chem, Baltimore, MD 21218 USA. RP Pacific NW Natl Lab, Div Chem Sci, Richland, WA 99352 USA. RI Haranczyk, Maciej/A-6380-2014 OI Haranczyk, Maciej/0000-0001-7146-9568 NR 58 TC 44 Z9 44 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD AUG 7 PY 2003 VL 107 IS 31 BP 7889 EP 7895 DI 10.1021/jp034640a PG 7 WC Chemistry, Physical SC Chemistry GA 708DF UT WOS:000184551300051 ER PT J AU Vaswani, HM Hsu, CP Head-Gordon, M Fleming, GR AF Vaswani, HM Hsu, CP Head-Gordon, M Fleming, GR TI Quantum chemical evidence for an intramolecular charge-transfer state in the carotenoid peridinin of peridinin-chlorophyll-protein SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID DENSITY-FUNCTIONAL THEORY; DONOR-ACCEPTOR SYSTEMS; LIGHT-HARVESTING COMPLEXES; RAMAN EXCITATION PROFILES; TRANSFER EXCITED-STATE; ENERGY-TRANSFER; PURPLE BACTERIA; AMPHIDINIUM-CARTERAE; ABSORPTION-SPECTRA; BETA-CAROTENE AB We present theoretical confirmation of an intramolecular charge-transfer (CT) state in peridinin in agreement with experimental results of Frank and co-workers (J. Phys. Chem. B 1999, 103, 8751 and J. Phys. Chem. B 2000, 104, 4569). Quantum chemical calculations using time-dependent density functional theory under the Tamm-Dancoff approximation were made on two structures: fully optimized peridinin and a molecule from the crystal structure of peridinin-chlorophyll-protein. The CT state appears as the third and second excited singlet state, respectively, for the two structures. A dipole-in-a-sphere model is used to estimate the solvation stabilization energies of each state in a variety of solvents. The energy of the CT state is shown to decrease dramatically in solvents of increasing polarity while the energy of the dark S-1 (Ag--like) state remains comparatively constant. C1 Univ Calif Berkeley, Dept Chem, Phys Biosci Div, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. Acad Sinica, Inst Chem, Taipei 115, Taiwan. RP Fleming, GR (reprint author), Univ Calif Berkeley, Dept Chem, Phys Biosci Div, Berkeley, CA 94720 USA. RI Hsu, Chao-Ping/E-1303-2011 OI Hsu, Chao-Ping/0000-0002-7187-427X NR 50 TC 123 Z9 124 U1 2 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD AUG 7 PY 2003 VL 107 IS 31 BP 7940 EP 7946 DI 10.1021/jp030086t PG 7 WC Chemistry, Physical SC Chemistry GA 708DF UT WOS:000184551300057 ER PT J AU Chen, Y Hu, DH Vorpagel, ER Lu, HP AF Chen, Y Hu, DH Vorpagel, ER Lu, HP TI Probing single-molecule T4 lysozyme conformational dynamics by intramolecular fluorescence energy transfer SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ENZYMATIC DYNAMICS; ALKALINE-PHOSPHATASE; CAVITY MUTANT; PROTEIN; SPECTROSCOPY; NMR; MOTIONS; SUBSTRATE; FLEXIBILITY; F-1-ATPASE AB We demonstrate the use of single-molecule spectroscopy to study enzyme conformational motions of T4 lysozyme under hydrolysis reaction of the polysaccharide walls of E. coli B cells. By attaching a donor-acceptor pair of dye molecules site-specifically to noninterfering sites on the enzyme, the hinge-bending motions of the enzyme are measured by monitoring the donor-acceptor emission intensity as a function of time. The overall enzymatic reaction rate constants are found to vary widely from molecule to molecule. The dominant contribution to this static inhomogeneity is attributed to enzyme searching for reactive sites on the substrate. We have also applied molecular dynamics simulation and a random-walk model to analyze the enzyme-substrate complex formation dynamics, revealing multiple intermediate conformational states in the chemical reaction process. This approach provides information about the microscopic conformational change drifting velocity, diffusion coefficient, friction coefficient, energy consumed by friction along the reaction coordinate, and energy landscape. C1 Pacific NW Natl Lab, Fundamental Sci Div, Richland, WA 99352 USA. RP Lu, HP (reprint author), Pacific NW Natl Lab, Fundamental Sci Div, POB 999, Richland, WA 99352 USA. RI Hu, Dehong/B-4650-2010 OI Hu, Dehong/0000-0002-3974-2963 NR 55 TC 68 Z9 69 U1 2 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD AUG 7 PY 2003 VL 107 IS 31 BP 7947 EP 7956 DI 10.1021/jp022406z PG 10 WC Chemistry, Physical SC Chemistry GA 708DF UT WOS:000184551300058 ER PT J AU Chakrabarti, S Bhattacharya, P Stiff-Roberts, AD Lin, YY Singh, J Lei, Y Browning, N AF Chakrabarti, S Bhattacharya, P Stiff-Roberts, AD Lin, YY Singh, J Lei, Y Browning, N TI Intersubband absorption in annealed InAs/GaAs quantum dots: a case for polarization-sensitive infrared detection SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID EMISSION; PHOTOCONDUCTIVITY; TEMPERATURE AB We have studied the characteristics of intersubband absorption of polarized infrared (IR) radiation in as-grown and annealed self-organized InAs/GaAs quantum dots. It is observed that with the increase of annealing time and temperature, the dots tend to flatten and behave more like quantum wells. As a result, their sensitivity to TE (in-plane)-polarized light decreases and that to TM (out-of-plane)-polarized light increases. The effect could be utilized for the realization of polarization-sensitive IR detectors. C1 Univ Michigan, Dept Elect Engn & Comp Sci, Ann Arbor, MI 48109 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Chakrabarti, S (reprint author), Univ Michigan, Dept Elect Engn & Comp Sci, Ann Arbor, MI 48109 USA. OI Browning, Nigel/0000-0003-0491-251X NR 14 TC 12 Z9 12 U1 0 U2 1 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 AUG 7 PY 2003 VL 36 IS 15 BP 1794 EP 1797 AR PII S0022-3727(03)63351-6 DI 10.1088/0022-3727/36/15/308 PG 4 WC Physics, Applied SC Physics GA 718NR UT WOS:000185153600009 ER PT J AU McDonald, RD Klehe, AK Singleton, J Hayes, W AF McDonald, RD Klehe, AK Singleton, J Hayes, W TI The pressure dependence of many-body interactions in the organic superconductor kappa-(BEDT-TTF)(2)Cu(SCN)(2) (BEDT-TTF bis(ethylene-dithio)tetrathiafulvalene): a comparison of high-pressure infrared reflectivity and Raman scattering experiments SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID CHARGE-TRANSFER SALTS; HIGH MAGNETIC-FIELDS; OPTICAL-PROPERTIES; DENSITY WAVES; CONDUCTIVITY; TEMPERATURE; CONDUCTORS; BIS(ETHYLENEDITHIO)TETRATHIAFULVALENE; SPECTROSCOPY; CONSTANTS AB We determine the pressure dependence of the electron-phonon coupling in kappa-(BEDT-TTF)(2)Cu(SCN)(2) by comparison of high-pressure Raman scattering and high-pressure infrared (IR) reflectivity measurements. The Raman active molecular vibrations of the BEDT-TTF dimers stiffen by 0.1-1% GPa(-1). In contrast, the corresponding modes in the IR spectrum are observed at lower frequency,with a pressure dependence of 0.5-5.5% GPa(-1), due to the influence of the electron-phonon interaction. Both dimer charge-oscillation and phase-phonon models are employed to extract the pressure dependence of the electron-molecular vibration coupling for these modes. Analysis of our data suggests that the reduction of electron-phonon coupling under pressure does not account for the previously observed suppression of superconductivity under pressure and that electron-electron interactions may contribute significantly to the pairing mechanism. C1 Los Alamos Natl Lab, NHMFL, Los Alamos, NM 87545 USA. Clarendon Lab, Dept Phys, Oxford OX1 3PU, England. RP McDonald, RD (reprint author), Los Alamos Natl Lab, NHMFL, MS-E536, Los Alamos, NM 87545 USA. RI McDonald, Ross/H-3783-2013 OI McDonald, Ross/0000-0002-0188-1087 NR 49 TC 4 Z9 4 U1 3 U2 8 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 AUG 6 PY 2003 VL 15 IS 30 BP 5315 EP 5332 AR PII S0953-8984(03)63148-6 DI 10.1088/0953-8984/15/30/313 PG 18 WC Physics, Condensed Matter SC Physics GA 718PT UT WOS:000185156200017 ER PT J AU Hastings, CA Lee, SY Cho, HS Yan, DL Kustu, S Wemmer, DE AF Hastings, CA Lee, SY Cho, HS Yan, DL Kustu, S Wemmer, DE TI High-resolution solution structure of the beryllofluoride-activated NtrC receiver domain SO BIOCHEMISTRY LA English DT Article ID HETERONUCLEAR NMR-SPECTROSCOPY; PULSED-FIELD GRADIENTS; NITROGEN REGULATOR-I; BINDING PROTEIN NTRC; ESCHERICHIA-COLI; SIGNAL-TRANSDUCTION; BACKBONE DYNAMICS; TRANSCRIPTIONAL ACTIVATION; CONFORMATIONAL-CHANGE; CRYSTAL-STRUCTURE AB Bacterial receiver domains mediate the cellular response to environmental changes through conformational changes induced by phosphorylation of a conserved aspartate residue. While the structures of several activated receiver domains have recently been determined, there is substantial variation in the conformational changes occurring upon activation. Here we present the high-resolution structure of the activated NtrC receiver domain (BeF3--NtrCr Complex) determined using NMR data, including residual dipolar couplings, yielding a family of structures with a backbone rmsd of 0.57 +/- 0.08 Angstrom, which is compared with the previous lower-resolution structure of the phosphorylated protein. Both phosphorylation and beryllofluoride addition induce a shift in register and an axial rotation of alpha-helix 4. In this high-resolution structure, we are able to observe a concerted change in the positions of Thr82 and Tyr101; this correlated change in two conserved residues (termed Y-T coupling) has been considered a general feature of the conformational change in receiver domains upon activation. In NtrC, this correlated side chain shift, leading to the helix reorientation, is distinctly different from the smaller reorganization seen in other activated receiver domains, and involves numerous other residues which do not participate in conformational changes seen in the other systems. Titration of the activated receiver domain with peptides from the NtrC ATPase domain provides direct evidence for interactions on the rearranged face of the receiver domain, which are likely to be responsible for enabling assembly into the active aggregate. Analysis of the active structure also suggests that His84 may play a role in controlling the phosphate hydrolysis rate. C1 Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Grad Grp Biophys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Plant & Microbial Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Wemmer, DE (reprint author), Lawrence Berkeley Lab, Phys Biosci Div, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [GM 38361, GM 62163] NR 59 TC 48 Z9 48 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD AUG 5 PY 2003 VL 42 IS 30 BP 9081 EP 9090 DI 10.1021/bi0273866 PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 707FE UT WOS:000184499000018 PM 12885241 ER PT J AU Lewis, EB Pfeiffer, BD Mathog, DR Celniker, SE AF Lewis, EB Pfeiffer, BD Mathog, DR Celniker, SE TI Evolution of the homeobox complex in the Diptera SO CURRENT BIOLOGY LA English DT Letter ID ANOPHELES-GAMBIAE; BITHORAX COMPLEX; GENE-COMPLEX; HOX GENES; DROSOPHILA; MOSQUITO; CLUSTER C1 CALTECH, Div Biol, Pasadena, CA 91125 USA. Lawrence Berkeley Natl Lab, Dept Genome Sci, Berkeley Drosophila Genome Project, Berkeley, CA 94720 USA. RP Lewis, EB (reprint author), CALTECH, Div Biol, Pasadena, CA 91125 USA. FU NICHD NIH HHS [HD06331] NR 19 TC 24 Z9 24 U1 0 U2 4 PU CELL PRESS PI CAMBRIDGE PA 1100 MASSACHUSETTS AVE, CAMBRIDGE, MA 02138 USA SN 0960-9822 J9 CURR BIOL JI Curr. Biol. PD AUG 5 PY 2003 VL 13 IS 15 BP R587 EP R588 DI 10.1016/S0960-9822(03)00520-7 PG 2 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 709PJ UT WOS:000184633300010 PM 12906807 ER PT J AU Knize, MG Salmon, CP Felton, JS AF Knize, MG Salmon, CP Felton, JS TI Mutagenic activity and heterocyclic amine carcinogens in commercial pet foods SO MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS LA English DT Article DE heterocyclic amine; mutagen; carcinogen; diet; pet food; companion animal ID FRIED GROUND-BEEF; 2-AMINO-1-METHYL-6-PHENYLIMIDAZO<4,5-B>PYRIDINE PHIP; MEAT-PRODUCTS; CANCER; DOGS; DIET; TEMPERATURE; HUMANS; CELLS; RISK AB Twenty-five commercial pet foods were analyzed for mutagenic activity using the Ames/Salmonella test with strain TA98 and added metabolic activation. All but one gave a positive mutagenic response. Fourteen of these samples were analyzed for heterocyclic amine mutagens/carcinogens and all but one contained 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MelQx) and 10 of 14 contained 2-amino-1-methyl-6-phenylimdazo[4,5-b]pyridine (PhIP) as analyzed by HPLC and confirmed by photodiode array peak matching. From these findings it is hypothesized that there is a connection between dietary heterocyclic amines and cancer in animals consuming these foods. (C) 2003 Elsevier B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Knize, MG (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. NR 31 TC 6 Z9 6 U1 3 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1383-5718 J9 MUTAT RES-GEN TOX EN JI Mutat. Res. Genet. Toxicol. Environ. Mutagen. PD AUG 5 PY 2003 VL 539 IS 1-2 BP 195 EP 201 DI 10.1016/S1383-5718(03)00164-5 PG 7 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 720EE UT WOS:000185247900020 PM 12948828 ER PT J AU Vocadlo, DJ Hang, HC Kim, EJ Hanover, JA Bertozzi, CR AF Vocadlo, DJ Hang, HC Kim, EJ Hanover, JA Bertozzi, CR TI A chemical approach for identifying O-GlcNAc-modified proteins in cells SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID LINKED N-ACETYLGLUCOSAMINE; NUCLEAR-PORE; TETRATRICOPEPTIDE REPEATS; INSULIN-RESISTANCE; SIALIC-ACID; UDP-GLCNAC; IN-VIVO; GLYCOSYLATION; TRANSFERASE; GLYCOPROTEINS AB The glycosylation of serine and threonine residues with a single GlcNAc moiety is a dynamic posttranslational modification of many nuclear and cytoplasmic proteins. We describe a chemical strategy directed toward identifying O-GlcNAc-modified proteins from living cells or proteins modified in vitro. We demonstrate, in vitro, that each enzyme in the hexosamine salvage pathway, and the enzymes that affect this dynamic modification (UDP-Glc-NAc:polypeptidtyltransferase and O-GlcNAcase), tolerate analogues of their natural substrates in which the N-acyl side chain has been modified to bear a bio-orthogonal azide moiety. Accordingly, treatment of cells with N-azidoacetylglucosamine results in the metabolic incorporation of the azido sugar into nuclear and cytoplasmic proteins. These O-azidoacetylglucosamine-modified proteins can be covalently derivatized with various biochemical probes at the site of protein glycosylation by using the Staudinger ligation. The approach was validated by metabolic labeling of nuclear pore protein p62, which is known to be posttranslationally modified with O-GlcNAc. This strategy will prove useful for both the identification of O-GlcNAc-modified proteins and the elucidation of the specific residues that bear this saccharide. C1 Lawrence Berkeley Natl Lab, Dept Chem, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Dept Mol & Cell Biol, Mat Sci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. NIDDKD, NIH, Bethesda, MD 20892 USA. RP Bertozzi, CR (reprint author), Lawrence Berkeley Natl Lab, Dept Chem, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. RI Vocadlo, David/E-5508-2014 OI Vocadlo, David/0000-0001-6897-5558 FU NIGMS NIH HHS [GM066047, R01 GM066047] NR 43 TC 294 Z9 302 U1 13 U2 69 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 AUG 5 PY 2003 VL 100 IS 16 BP 9116 EP 9121 DI 10.1073/pnas.1632821100 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 709HP UT WOS:000184620000006 PM 12874386 ER PT J AU Moule, AJ Spence, MM Han, SI Seeley, JA Pierce, KL Saxena, S Pines, A AF Moule, AJ Spence, MM Han, SI Seeley, JA Pierce, KL Saxena, S Pines, A TI Amplification of xenon NMR and MRI by remote detection SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; MULTIPLE-QUANTUM NMR; NOBLE-GAS; POLARIZATION; XE-129; FIELD AB A technique is proposed in which an NMR spectrum or MRI is encoded and stored as spin polarization and is then moved to a different physical location to be detected. Remote detection allows the separate optimization of the encoding and detection steps, permitting the independent choice of experimental conditions and excitation and detection methodologies. In the initial experimental demonstration of this technique, we show that taking dilute Xe-129 from a porous sample placed inside a large encoding coil and concentrating it into a smaller detection coil can amplify NMR signal. In general, the study of NMR active molecules at low concentration that have low physical filling factor is facilitated by remote detection. In the second experimental demonstration, MRI information encoded in a very low-field magnet (4-7 mT) is transferred to a high-field magnet (4.2 T) to be detected under optimized conditions. Furthermore, remote detection allows the utilization of ultrasensitive optical or superconducting quantum interference device detection techniques, which broadens the horizon of NMR experimentation. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. ETH, Chem Phys Lab, CH-8093 Zurich, Switzerland. Univ Pittsburgh, Dept Chem, Pittsburgh, PA 15260 USA. RP Pines, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Han, Songi/E-4723-2012; Moule, Adam/B-9484-2013; OI Han, Songi/0000-0001-6489-6246; Moule, Adam/0000-0003-1354-3517; Saxena, Sunil/0000-0001-9098-6114 NR 28 TC 84 Z9 85 U1 2 U2 19 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 AUG 5 PY 2003 VL 100 IS 16 BP 9122 EP 9127 DI 10.1073/pnas.1133497100 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 709HP UT WOS:000184620000007 PM 12876195 ER PT J AU Lichtenegger, HC Schoberl, T Ruokolainen, JT Cross, JO Heald, SM Birkedal, H Waite, JH Stucky, GD AF Lichtenegger, HC Schoberl, T Ruokolainen, JT Cross, JO Heald, SM Birkedal, H Waite, JH Stucky, GD TI Zinc and mechanical prowess in the jaws of Nereis, a marine worm SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID BINDING-SITES; CHITONS POLYPLACOPHORA; POLYCHAETE JAWS; MANDIBLES; METAL; TEETH; SCATTERING; HARDNESS; COMPONENT; MANGANESE AB Higher animals typically rely on calcification to harden certain tissues such as bones and teeth. Some notable exceptions can be found in invertebrates: The fangs, teeth, and mandibles of diverse arthropod species have been reported to contain high levels of zinc. Considerable quantities of zinc also occur in the jaws of the marine polychaete worm Nereis sp. High copper levels in the polychaete worm Glycera dibranchiata recently were attributed to a copper-based biomineral reinforcing the jaws. In the present article, we attempt to unravel the role of zinc in Nereis limbata jaws, using a combination of position-resolved state-of-the-art techniques. It is shown that the local hardness and stiffness of the jaws correlate with the local zinc concentration, pointing toward a structural role for zinc. Zinc always is detected in tight correlation with chlorine, suggesting the presence of a zinc-chlorine compound. No crystalline inorganic phase was found, however, and results from x-ray absorption spectroscopy further exclude the presence of simple inorganic zinc-chlorine compounds in amorphous form. The correlation of local histidine levels in the protein matrix and zinc concentration leads us to hypothesize a direct coordination of zinc and chlorine to the protein. A comparison of the role of the transition metals zinc and copper in the jaws of two polychaete worm species Nereis and Glycera, respectively, is presented. C1 Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Mol Cellular & Dev Biol, Santa Barbara, CA 93106 USA. Vienna Tech Univ, Dept Mat Sci & Testing, A-1040 Vienna, Austria. Austrian Acad Sci, Erich Schmid Inst Festkorperphys, A-8700 Leoben, Austria. Helsinki Univ Technol, Dept Engn Phys & Math, Opt & Mol Mat, Espoo 02015, Finland. Argonne Natl Lab, Adv Photon Source, Pacific NW Consortium Collaborat Access Team, Argonne, IL 60439 USA. RP Lichtenegger, HC (reprint author), Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA. RI Ruokolainen, Janne/F-6369-2010; OI Lichtenegger, Helga/0000-0002-6624-1419; Birkedal, Henrik/0000-0002-4201-2179 NR 32 TC 79 Z9 79 U1 3 U2 39 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 AUG 5 PY 2003 VL 100 IS 16 BP 9144 EP 9149 DI 10.1073/pnas.1632658100 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 709HP UT WOS:000184620000011 PM 12886017 ER PT J AU Mulichak, AM Losey, HC Lu, W Wawrzak, Z Walsh, CT Garavito, RM AF Mulichak, AM Losey, HC Lu, W Wawrzak, Z Walsh, CT Garavito, RM TI Structure of the TDP-epi-vancosaminyltransferase GtfA from the chloroeremomycin biosynthetic pathway SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID ESCHERICHIA-COLI MURG; CRYSTAL-STRUCTURE; GLYCOPEPTIDE ANTIBIOTICS; PEPTIDOGLYCAN BIOSYNTHESIS; STREPTOMYCES-ANTIBIOTICUS; BETA-GLUCOSYLTRANSFERASE; VANCOMYCIN; GLYCOSYLTRANSFERASES; MECHANISM; PURIFICATION AB During the biosynthesis of the vancomycin-class antibiotic chloroeremomycin, TDP-epi-vancosaminyltransferase GtfA catalyzes the attachment of 4-epi-vancosamine from a TDP donor to the beta-OH-Tyr-6 of the aglycone cosubstrate. Glycosyltransferases from this pathway are potential tools for the combinatorial design of new antibiotics that are effective against vancomycin-resistant bacterial strains. These enzymes are members of the GT-B glycosyltransferase superfamily, which share a homologous bidomain topology. We present the 2.8-Angstrom crystal structures of GtfA complexes with vancomycin and the natural monoglycosylated peptide substrate, representing the first direct observation of acceptor substrate binding among closely related glycosyltransferases. The acceptor substrates bind to the N-terminal domain such that the aglycone substrate's reactive hydroxyl group hydrogen bonds to the side chains of Ser-10 and Asp-13, thus identifying these as residues of potential catalytic importance. As well as an open form of the enzyme, the crystal structures have revealed a,closed form in which a TDP ligand is bound at a donor substrate site in the interdomain cleft, thereby illustrating not only binding interactions, but the conformational changes in the enzyme that accompany substrate binding. C1 Michigan State Univ, Dept Biochem & Mol Biol, E Lansing, MI 48824 USA. Harvard Univ, Sch Med, Dept Biol Chem & Mol Pharmacol, Boston, MA 02115 USA. Argonne Natl Lab, DuPont NW Dow Collaborat Access Team, Argonne, IL 60439 USA. RP Garavito, RM (reprint author), Michigan State Univ, Dept Biochem & Mol Biol, E Lansing, MI 48824 USA. FU PHS HHS [49338] NR 30 TC 112 Z9 119 U1 2 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 AUG 5 PY 2003 VL 100 IS 16 BP 9238 EP 9243 DI 10.1073/pnas.1233577100 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 709HP UT WOS:000184620000027 PM 12874381 ER PT J AU Dumas, P Miller, L AF Dumas, P Miller, L TI The use of synchrotron infrared microspectroscopy in biological and biomedical investigations SO VIBRATIONAL SPECTROSCOPY LA English DT Article; Proceedings Paper CT 2nd Conference on Shedding New Light on Disease CY JUN 23-27, 2002 CL REIMS, FRANCE DE synchrotron; infrared; microscopy; hair; skin; cells ID MODEL STRATUM-CORNEUM; HUMAN TISSUE; HUMAN HAIR; SPECTROSCOPY; RADIATION; MICROSCOPY; CELLS; SKIN; MIXTURES; PHASES AB Synchrotron radiation is a bright source of infrared (IR) photons. It has been exploited in microscopy, where much smaller areas can be probed. with sizes close to the diffraction limit. The experiments have been performed at two beamlines, one at the National Synchrotron Light Source (USA) and one at SuperACO, LURE (France). The potentiality of this microanalytical synchrotron-based technique is particularly well documented in the study of individual cells: functional groups imaging representing biochemical changes have been obtained at various states of mitosis and apoptosis. The higher spatial resolution and spectral quality achieved allows investigating biological tissues in more detail. In this work, this is exemplified in the study of human hair and skin, where, in both cases, highly localized compounds have been evidenced in specific areas of the analyzed tissues: high lipid concentration inside the hair medulla, and inside the Stratum Corneum (SC) of skin. Moreover, the lineshape and frequency position of the CH2 stretching mode indicates a highly ordered phase extending over almost all the Stratum Comeum. The penetration pathway of an external agent has been also studied for both hair and skin. It is clear that synchrotron-based infrared microspectroscopy is an extremely valuable analytical tool when determining the spatially resolved chemical composition of biological and biomedical samples. In the future, the combination of infrared microspectroscopy with other synchrotron-based microscopic techniques, such as X-ray microscopy, at the same sample location is discussed. (C) 2003 Elsevier B.V. All rights reserved. C1 Ctr Univ Paris Sud, LURE, F-91898 Orsay, France. Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. RP Dumas, P (reprint author), Ctr Univ Paris Sud, LURE, Bat 209D, F-91898 Orsay, France. NR 50 TC 124 Z9 124 U1 2 U2 23 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-2031 J9 VIB SPECTROSC JI Vib. Spectrosc. PD AUG 5 PY 2003 VL 32 IS 1 BP 3 EP 21 DI 10.1016/S0924-2031(03)00043-2 PG 19 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 707ME UT WOS:000184513800002 ER PT J AU Tardio, M Ramirez, R Gonzalez, R Chen, Y Kokta, MR AF Tardio, M Ramirez, R Gonzalez, R Chen, Y Kokta, MR TI Photochromic effect in magnesium-doped alpha-Al2O3 single crystals SO APPLIED PHYSICS LETTERS LA English DT Article ID ELECTRON-SPIN-RESONANCE; HIGH-TEMPERATURE; TRAPPED-HOLE; MGO; CONDUCTIVITY; DEFECTS; SRTIO3; LI AB A reversible photochromic effect was investigated in Mg-doped alpha-Al2O3 single crystals oxidized at elevated temperatures. Alternate illumination with blue and UV light at Tless than or equal to210 K results in reversible disappearance and reappearance of a gray-purple coloration, respectively. The coloration can also be fully rejuvenated by warming the crystal to Tgreater than or equal to215 K. (C) 2003 American Institute of Physics. C1 Univ Carlos III Madrid, Dept Fis, Escuela Politecn Super, Madrid 28911, Spain. US DOE, Div Mat Sci, Off Basic Energy Sci, Germantown, MD 20874 USA. St Gobain Crystals & Detectors, Washougal, WA 98671 USA. RP Tardio, M (reprint author), Univ Carlos III Madrid, Dept Fis, Escuela Politecn Super, Avda Univ 30, Madrid 28911, Spain. RI Ramirez Jimenez, Rafael/I-1769-2015; TARDIO LOPEZ, MIGUEL M./G-3177-2016 OI TARDIO LOPEZ, MIGUEL M./0000-0001-7413-0009 NR 21 TC 7 Z9 7 U1 0 U2 2 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 AUG 4 PY 2003 VL 83 IS 5 BP 881 EP 883 DI 10.1063/1.1597963 PG 3 WC Physics, Applied SC Physics GA 706UT UT WOS:000184474000023 ER PT J AU Johnston, SW Crandall, RS Yelon, A AF Johnston, SW Crandall, RS Yelon, A TI Evidence of the Meyer-Neldel rule in InGaAsN alloys and the problem of determining trap capture cross sections SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; DEEP-LEVEL DEFECTS; P-TYPE; TRANSIENT SPECTROSCOPY; SOLAR-CELLS; GAINNAS; GAAS; SEMICONDUCTORS; ENERGY; ORIGIN AB Deep-level transient spectroscopy measurements have been performed on the quaternary semiconductor InGaAsN. A series of as-grown and annealed metalorganic chemical-vapor-deposited and molecular-beam-epitaxy samples with varying composition were studied. We observed a deep hole trap with activation energy ranging between 0.5 and 0.8 eV in all samples. The data clearly obey the Meyer-Neldel rule (MNR) with an isokinetic temperature of 350 K. We show that great care must be used in extracting capture cross sections (sigma) from materials that obey the MNR. In fact, we argue that it is probably not possible to determine sigma from the detrapping rate alone. One must measure both trapping and detrapping rates. (C) 2003 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Ecole Polytech Montreal, Montreal, PQ H3C 3A7, Canada. RP Johnston, SW (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 29 TC 13 Z9 13 U1 1 U2 2 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 AUG 4 PY 2003 VL 83 IS 5 BP 908 EP 910 DI 10.1063/1.1596713 PG 3 WC Physics, Applied SC Physics GA 706UT UT WOS:000184474000032 ER PT J AU Baikalov, A Wang, YQ Shen, B Lorenz, B Tsui, S Sun, YY Xue, YY Chu, CW AF Baikalov, A Wang, YQ Shen, B Lorenz, B Tsui, S Sun, YY Xue, YY Chu, CW TI Field-driven hysteretic and reversible resistive switch at the Ag-Pr0.7Ca0.3MnO3 interface SO APPLIED PHYSICS LETTERS LA English DT Article ID DOPED LAMNO3; THIN-FILMS; MANGANITES; TRANSPORT; MAGNETORESISTANCE; HETEROSTRUCTURES AB The hysteretic and reversible polarity-dependent resistive switch driven by electric pulses is studied in both Ag/Pr0.7Ca0.3MnO3/YBa2Cu3O7 sandwiches and single-layer Pr0.7Ca0.3MnO3 strips. The data demonstrate that the switch takes place at the Ag-Pr0.7Ca0.3MnO3 interface. A model, which describes the data well, is proposed. We further suggest that electrochemical migration is the cause for the switch. (C) 2003 American Institute of Physics. C1 Univ Houston, Dept Phys, Houston Sci Ctr 202, Houston, TX 77204 USA. Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Hong Kong Univ Sci & Technol, Hong Kong, Hong Kong, Peoples R China. RP Baikalov, A (reprint author), Univ Houston, Dept Phys, Houston Sci Ctr 202, Houston, TX 77204 USA. NR 16 TC 345 Z9 353 U1 5 U2 57 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 AUG 4 PY 2003 VL 83 IS 5 BP 957 EP 959 DI 10.1063/1.1590741 PG 3 WC Physics, Applied SC Physics GA 706UT UT WOS:000184474000049 ER PT J AU Maher, K DePaolo, DJ Conrad, ME Serne, RJ AF Maher, K DePaolo, DJ Conrad, ME Serne, RJ TI Vadose zone infiltration rate at Hanford, Washington, inferred from Sr isotope measurements SO WATER RESOURCES RESEARCH LA English DT Article DE infiltration rate; vadose; Sr isotopes; Hanford ID SOIL CHRONOSEQUENCE; GROUNDWATER SYSTEMS; WEATHERING RATE; YUCCA-MOUNTAIN; SURFACE-AREA; CONSTRAINTS; DISSOLUTION; EVOLUTION; RATIOS; MODEL AB Sr isotope ratios were measured in the pore water, acid extracts, and sediments of a 70-m vadose zone core to obtain estimates of the long-term infiltration flux for a site in the Hanford/DOE complex in eastern Washington State. The Sr-87/Sr-86 values for the pore waters decrease systematically with depth, from a high value of 0.721 near the surface toward the bulk sediment average value of 0.711. Estimates of the bulk weathering rate combined with Sr isotopic data were used to constrain the long-term (century to millenial scale) natural diffuse infiltration flux for the site given both steady state and nonsteady state conditions. The models suggest that the infiltration flux for the site is 7 +/- 3 mm/yr. The method shows potential for providing long-term in situ estimates of infiltration rates for deep heterogeneous vadose zones. C1 Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Maher, K (reprint author), Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. RI Conrad, Mark/G-2767-2010; Maher, Kate/B-3489-2010 OI Maher, Kate/0000-0002-5982-6064 NR 40 TC 15 Z9 15 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD AUG 2 PY 2003 VL 39 IS 8 AR 1204 DI 10.1029/2002WR001742 PG 14 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 710ZJ UT WOS:000184712400003 ER PT J AU Schlueter, JA Geiser, U AF Schlueter, JA Geiser, U TI Potassium dicyanoargentate(I) 1,4,7,10,13,16-hexaoxacyclooctadecane SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID COMPLEXES AB The crystal structure of the title compound, K[Ag(CN)(2)].-C12H24O6, conventionally denoted K(18-crown-6)Ag(CN)(2), where 18-crown-6 is 1,4,7,10,13,16-hexaoxacyclooctadecane, is characterized by closely packed linear chains formed by the coordination of the nitrile N atoms of the [Ag(CN)(2)](-). anions to the K+ cations. The K atoms lie on centers of inversion and are additionally bound to the six O atoms of the crown ether. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Schlueter, JA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 17 TC 4 Z9 4 U1 0 U2 0 PU BLACKWELL MUNKSGAARD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD AUG PY 2003 VL 59 BP M325 EP M327 DI 10.1107/S0108270103014318 PN 8 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 708CP UT WOS:000184549800016 PM 12909757 ER PT J AU Collis, GE Burrell, AK John, KD Plieger, PG AF Collis, GE Burrell, AK John, KD Plieger, PG TI 7-bromoquinolin-8-ol SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID CMAP-OXINE; CRYSTAL; BROMINATION; PHENOLS AB Structure analysis of the title compound, C9H6BrNO, has established that bromination of an 8-hydroxyquinoline derivative occurred in the 7-position. Intermolecular and weak intramolecular O-H...N hydrogen bonds are present, the former causing the molecules to pack as hydrogen-bonded dimers in the solid state. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Burrell, AK (reprint author), Los Alamos Natl Lab, MS J514, Los Alamos, NM 87545 USA. RI Collis, Gavin/D-6343-2011; OI John, Kevin/0000-0002-6181-9330 NR 18 TC 4 Z9 4 U1 0 U2 2 PU BLACKWELL MUNKSGAARD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD AUG PY 2003 VL 59 BP O443 EP O444 DI 10.1107/S0108270103013714 PN 8 PG 2 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 708CP UT WOS:000184549800032 PM 12909773 ER PT J AU Rodriguez, MA Bunge, SD AF Rodriguez, MA Bunge, SD TI Diphenylamine SO ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE LA English DT Article ID REACTIVITY; AMIDES AB In the title compound, C12H11N, two phenyl rings are bound to a central N atom. These rings are rotated with respect to one another by an average dihedral angle of 43 (5)degrees. There are eight unique molecules in the asymmetric unit and a total of 16 molecules in the unit cell. The compound displays an interesting packing structure, where phenyl rings display both layered packing to nearest neighbors as well as rotation of phenyl rings to pack perpendicular to one other. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Rodriguez, MA (reprint author), Sandia Natl Labs, POB 5800,MS 1411, Albuquerque, NM 87185 USA. NR 6 TC 14 Z9 14 U1 0 U2 6 PU BLACKWELL MUNKSGAARD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 1600-5368 J9 ACTA CRYSTALLOGR E JI Acta Crystallogr. Sect. E.-Struct Rep. Online PD AUG PY 2003 VL 59 BP O1123 EP O1125 DI 10.1107/S1600536803014788 PN 8 PG 3 WC Crystallography SC Crystallography GA 706UV UT WOS:000184474200072 ER PT J AU Zhang, XF Yang, Q De Jonghe, LC AF Zhang, XF Yang, Q De Jonghe, LC TI Microstructure development in hot-pressed silicon carbide: effects of aluminum, boron, and carbon additives SO ACTA MATERIALIA LA English DT Article DE silicon carbides; microstructure; phase transformations; grain boundary structure; TEM ID CRACK DEFLECTION PROCESSES; GRAIN-BOUNDARIES; HEAT-TREATMENT; C-ADDITIONS; WEIGHT-LOSS; BEHAVIOR; GROWTH; PHASE; AL; TRANSFORMATION AB SiC was hot-pressed with aluminum, boron, and carbon additives. The Al content was modified either to obtain SiC samples containing a continuous Al gradient, or to vary the average Al content. In both cases, it was found that increasing Al content resulted in decreased number density but dramatically enhanced aspect ratio of the elongated SiC grains. Amorphous-to-crystalline transformation was also confirmed in grain boundary films when Al content exceeded 4 wt%. In addition, increasing Al decreased the degree of cubic-to-hexagonal SiC phase transformation. Similar processing and characterization were done with modified boron and carbon average contents. The systematic experiments demonstrated that boron and carbon promoted formation of elongated grains through promoting 3C-to-4H SiC phase transformation during hot pressing. The experiments also clarified the mechanical property responses to microstructural modification. Tailoring of the SiC microstructure to suit different applications would be possible. Published by Elsevier Science Ltd on behalf of Acta Materialia Inc. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Zhang, XF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. NR 51 TC 35 Z9 38 U1 3 U2 15 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 AUG 1 PY 2003 VL 51 IS 13 BP 3849 EP 3860 DI 10.1016/S1359-6454(03)00209-X PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 704XC UT WOS:000184366100016 ER PT J AU Hill, MR DeWald, AT Demma, AG Hackel, LA Chen, HL Dane, CB Specht, RC Harris, FB AF Hill, MR DeWald, AT Demma, AG Hackel, LA Chen, HL Dane, CB Specht, RC Harris, FB TI Laser peening technology SO ADVANCED MATERIALS & PROCESSES LA English DT Article C1 Univ Calif Davis, Dept Mech & Aeronaut Engn, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Laser Sci & Technol Program, Livermore, CA 94550 USA. Metal Improvement Co, Livermore, CA USA. RP Hill, MR (reprint author), Univ Calif Davis, Dept Mech & Aeronaut Engn, 1 Shields Ave, Davis, CA 95616 USA. RI Hill, Michael/A-2525-2016 OI Hill, Michael/0000-0002-9168-211X NR 0 TC 16 Z9 17 U1 0 U2 10 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 0882-7958 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD AUG PY 2003 VL 161 IS 8 BP 65 EP 67 PG 3 WC Materials Science, Multidisciplinary SC Materials Science GA 711CR UT WOS:000184722100007 ER PT J AU Bryant, SL Paruchuri, RK Saripalli, KP AF Bryant, SL Paruchuri, RK Saripalli, KP TI Flow and solute transport around injection wells through a single, growing fracture SO ADVANCES IN WATER RESOURCES LA English DT Article DE injection wells; growing fracture; elliptical flow field; solute transport ID CONTAMINANT TRANSPORT; MATRIX DIFFUSION; POROUS-MEDIA; MIGRATION; ROCK AB During deep-well injection of liquids, the formation around an injection well is often fractured due to an imbalance between the injection pressure and the minimum horizontal rock stress opposing fracturing. The resulting fractures can grow during injection, which may span over several months to years. Earlier studies reported on solute transport in a single fracture in low permeability fractured media, assuming that transport into the formation perpendicular to the face of the fracture is mediated by diffusion alone. This may be valid for flow under natural gradients through fractured formations of low permeability. In contrast, due to the high rates of injection through a fractured injection well, both advection and dispersion play an important role in the spread of contaminants around a fractured injection well. We present a model for the flow and reactive solute transport profiles around fractured injection wells, through a single, two-winged vertical fracture created by injection at high rates and/or pressures and growing with time. The fracture, of constant height and infinite conductivity, serves as a line source injecting fluids into the formation perpendicular to its face via a uniform leak-off, resulting in an elliptical water flood front confocal with the fracture. Flow and solute transport within the elliptical flow domain is formulated as a planar (two-dimensional) transport problem, described by the advection-dispersion equation in elliptical coordinates including retardation and 1 st order radioactive nuclear decay processes. Results indicate that transport at early times depends strongly on location relative to the fracture. Retardation has a more pronounced influence on transport for the cases where advection is significant; whereas 1 st order radioactive nuclear decay process is independent of advective velocity. Flow and transport around an injection well with a vertical fracture exhibits important differences from radial transport that neglects the presence of the fracture, and also from transport from a fracture of constant length. The model and findings presented have applications in the calculation of the fate and transport of contaminants around fractured injectors and modeling the resulting contaminant plumes down stream of the wells. Further, the model also serves as a basis for modeling enhanced remediation of contaminated rock via injection well fracturing, a recently demonstrated technology. (C) 2003 Elsevier Ltd. All rights reserved. C1 Univ Texas, Dept Petr & Geosyst Engn, Austin, TX 78712 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bryant, SL (reprint author), Univ Texas, Dept Petr & Geosyst Engn, Austin, TX 78712 USA. NR 26 TC 1 Z9 3 U1 0 U2 5 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 AUG PY 2003 VL 26 IS 8 BP 803 EP 813 DI 10.1016/S0309-1708(03)00065-4 PG 11 WC Water Resources SC Water Resources GA 702QV UT WOS:000184235300001 ER PT J AU Farthing, MW Kees, CE Coffey, TS Kelley, CT Miller, CT AF Farthing, MW Kees, CE Coffey, TS Kelley, CT Miller, CT TI Efficient steady-state solution techniques for variably saturated groundwater flow SO ADVANCES IN WATER RESOURCES LA English DT Article DE Richards' equation; steady-state; pseudo-transient continuation ID CONSERVATIVE NUMERICAL-SOLUTION; FINITE-ELEMENT METHOD; RICHARDS EQUATION; POROUS-MEDIA; HYDRAULIC CONDUCTIVITY; UNSATURATED FLOW; MULTIPHASE FLOW; SOILS; FORM; INFILTRATION AB We consider the simulation of steady-state variably saturated groundwater flow using Richards' equation (RE). The difficulties associated with solving RE numerically are well known. Most discretization approaches for RE lead to nonlinear systems that are large and difficult to solve. The solution of nonlinear systems for steady-state problems can be particularly challenging, since a good initial guess for the steady-state solution is often hard to obtain, and the resulting linear systems may be poorly scaled. Common approaches like Picard iteration or variations of Newton's method have their advantages but perform poorly with standard globalization techniques under certain conditions. Pseudo-transient continuation has been used in computational fluid dynamics for some time to obtain steady-state solutions for problems in which Newton's method with standard line-search strategies fails. Here, we examine the use of pseudo-transient continuation as well as Newton's method combined with standard globalization techniques for steady-state problems in heterogeneous domains. We investigate the methods' performance with direct and preconditioned Krylov iterative linear solvers. We then make recommendations for robust and efficient approaches to obtain steady-state solutions for RE under a range of conditions. Published by Elsevier Ltd. C1 Univ N Carolina, Ctr Adv Study Environm, Dept Environm Sci & Engn, Chapel Hill, NC 27599 USA. N Carolina State Univ, Dept Math, Ctr Res Sci Computat, Raleigh, NC 27695 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Farthing, MW (reprint author), Univ N Carolina, Ctr Adv Study Environm, Dept Environm Sci & Engn, Chapel Hill, NC 27599 USA. RI Kelley, Carl/A-4549-2008; Miller, Cass T./I-6613-2012 OI Miller, Cass T./0000-0001-6082-9273 NR 40 TC 25 Z9 25 U1 0 U2 4 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 AUG PY 2003 VL 26 IS 8 BP 833 EP 849 DI 10.1016/S0309-1708(03)00076-9 PG 17 WC Water Resources SC Water Resources GA 702QV UT WOS:000184235300003 ER PT J AU Chen, LS Huang, SR Lee, L Davalos, A Schiestl, RH Campisi, J Oshima, J AF Chen, LS Huang, SR Lee, L Davalos, A Schiestl, RH Campisi, J Oshima, J TI WRN, the protein deficient in Werner syndrome, plays a critical structural role in optimizing DNA repair SO AGING CELL LA English DT Article DE DNA; double-strand break; human; recombination; Werner ID RECQ FAMILY HELICASES; V(D)J RECOMBINATION; BLOOMS-SYNDROME; FUNCTIONAL INTERACTION; HOLLIDAY JUNCTIONS; SYNDROME GENE; REPLICATION; EXONUCLEASE; COLOCALIZES; COMPLEX AB Werner syndrome (WS) predisposes patients to cancer and premature aging, owing to mutations in WRN. The WRN protein is a RECQ-Iike helicase and is thought to participate in DNA double-strand break (DSB) repair by non-homologous end joining (NHEJ) or homologous recombination (HR). It has been previously shown that non-homologous DNA ends develop extensive deletions during repair in WS cells, and that this WS phenotype was complemented by wild-type (wt) WRN. WRN possesses both 3' --> 5' exonuclease and 3'--> 5' helicase activities. To determine the relative contributions of each of these distinct enzymatic activities to DSB repair, we examined NHEJ and HR in WS cells (WRN-/-) complemented with either wtWRN, exonuclease-defective WRN (E-), helicase-defective WRN (H-) or exonuclease/helicase-defective WRN (E-H-). The single E-and H- mutants each partially complemented the NHEJ abnormality of WRN-/- cells. Strikingly, the E-H- double mutant complemented the WS deficiency nearly as efficiently as did wtWRN. Similarly, the double mutant complemented the moderate HR deficiency of WS cells nearly as well as did wtWRN, whereas the E- and H- single mutants increased HR to levels higher than those restored by either E-H- or wtWRN. These results suggest that balanced exonuclease and helicase activities of WRN are required for optimal HR. Moreover, WRN appears to play a structural role, independent of its enzymatic activities, in optimizing HR and efficient NHEJ repair. Another human RECQ helicase, BLM, suppressed HR but had little or no effect on NHEJ, suggesting that mammalian RECQ helicases have distinct functions that can finely regulate recombination events. C1 Univ Washington, Dept Pathol, Seattle, WA 98195 USA. Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Los Angeles, Dept Pathol, Los Angeles, CA 90095 USA. RP Oshima, J (reprint author), Univ Washington, Dept Pathol, Box 357470, Seattle, WA 98195 USA. FU NCI NIH HHS [CA78088]; NIA NIH HHS [AG11658, AG14446] NR 44 TC 77 Z9 78 U1 1 U2 5 PU BLACKWELL PUBL LTD PI OXFORD PA 108 COWLEY RD, OXFORD OX4 1JF, OXON, ENGLAND SN 1474-9718 J9 AGING CELL JI Aging Cell PD AUG PY 2003 VL 2 IS 4 BP 191 EP 199 DI 10.1046/j.1474-9728.2003.00052.x PG 9 WC Cell Biology; Geriatrics & Gerontology SC Cell Biology; Geriatrics & Gerontology GA 709WJ UT WOS:000184649300001 PM 12934712 ER PT J AU Tsouris, C Culbertson, CT DePaoli, DW Jacobson, SC de Almeida, VF Ramsey, JM AF Tsouris, C Culbertson, CT DePaoli, DW Jacobson, SC de Almeida, VF Ramsey, JM TI Electrohydrodynamic mixing in microchannels SO AICHE JOURNAL LA English DT Article ID CAPILLARY-ELECTROPHORESIS; PCR AMPLIFICATION; POSTCOLUMN REACTOR; ANALYSIS SYSTEMS; MICROCHIP; LIQUIDS; DEVICES; CHIPS AB Electrohydrodynamic flow generated by the motion of charge carriers in an electric field was investigated for rapid mixing in microchannel devices. A "tee" geometry of channels ranging from 40 to 110 mum in width and 30 to 60 mum in depth was used to contact two miscible fluids, such as alcohols. A fluorescent dye (Rhodamine B) was used to quantify mixing. A potential difference ranging from 0 to 900 V was applied between two electrodes separated by a distance of 450 mum, resulting in field strengths ranging from 0 to 2 x 10(6) V/m. Results show that when no electric field is applied, mixing of the two streams is driven by diffusion and is, therefore, slow. The mixing length, at which the concentration across the channel becomes essentially uniform, decrease significantly as the applied voltage was increased. There seems to be a threshold of applied voltage below which mixing is not enhanced by the electric field under the conditions studied. In strong electric fields, the mixing length was less than 150 mum, while in the absence of an electric field, the mixing length was greater than 5, 000 mum. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tsouris, C (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Tsouris, Costas/C-2544-2016; de Almeida, Valmor/P-5498-2016 OI Tsouris, Costas/0000-0002-0522-1027; de Almeida, Valmor/0000-0003-0899-695X NR 34 TC 19 Z9 19 U1 1 U2 8 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 3 PARK AVE, NEW YORK, NY 10016-5901 USA SN 0001-1541 J9 AICHE J JI AICHE J. PD AUG PY 2003 VL 49 IS 8 BP 2181 EP 2186 DI 10.1002/aic.690490825 PG 6 WC Engineering, Chemical SC Engineering GA 712JX UT WOS:000184795500024 ER PT J AU Zheng, JJ Yeung, ES AF Zheng, JJ Yeung, ES TI Mechanism for the separation of large molecules based on radial migration in capillary electrophoresis SO ANALYTICAL CHEMISTRY LA English DT Article ID FIELD-FLOW FRACTIONATION; SINGLE-DNA-MOLECULES; GEL-ELECTROPHORESIS; RESTRICTION FRAGMENTS; POROUS-MEDIA; PLASMID DNA; COMBINATION; STRENGTH AB We demonstrate a novel separation mechanism for large molecules based on their radial migration in capillary electrophoresis with applied hydrodynamic flow (HDF). The direction of radial migration depends on the direction of the applied HDF relative to the electric field. The radial migration velocities are size-dependent, which could be attributed to the different degree of deformation under shear flow. Analytical separation was demonstrated on a sample plug containing;. DNA (48 502 bp) and phiX174 RF DNA (5386 bp) with baseline separation. Alternatively, this separation mode can be performed continuously and is thus applicable to preparative separations. Without the need for gel/polymer or complex instrumentation, this separation technique is complementary to capillary gel electrophoresis and field-flow fractionation. Although large DNA molecules were used to demonstrate the separation mechanism here, these protocols could also be applied to the separation of proteins, cells, or particles based on size, shape, or deformability. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Yeung, ES (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. NR 27 TC 35 Z9 35 U1 1 U2 7 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 AUG 1 PY 2003 VL 75 IS 15 BP 3675 EP 3680 DI 10.1021/ac034430u PG 6 WC Chemistry, Analytical SC Chemistry GA 709WV UT WOS:000184650300006 PM 14572029 ER PT J AU Moxom, J Reilly, PTA Whitten, WB Ramsey, M AF Moxom, J Reilly, PTA Whitten, WB Ramsey, M TI Analysis of volatile organic compounds in air with a micro ion trap mass analyzer SO ANALYTICAL CHEMISTRY LA English DT Article ID PER-TRILLION LEVELS; SPECTROMETRY; IONIZATION; WATER AB Analysis of several volatile organic compounds in air has been demonstrated with a micro ion trap mass analyzer equipped with a semipermeable membrane sampling inlet MS/MS of selected compounds was also shown to be feasible with the miniature ion trap and could be used to improve sensitivity by reducing background noise. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Whitten, WB (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 19 TC 26 Z9 26 U1 1 U2 11 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 AUG 1 PY 2003 VL 75 IS 15 BP 3739 EP 3743 DI 10.1021/ac034043k PG 5 WC Chemistry, Analytical SC Chemistry GA 709WV UT WOS:000184650300015 PM 14572038 ER PT J AU Ramsey, JD Jacobson, SC Culbertson, CT Ramsey, JM AF Ramsey, JD Jacobson, SC Culbertson, CT Ramsey, JM TI High-efficiency, two-dimensional separations of protein digests on microfluidic devices SO ANALYTICAL CHEMISTRY LA English DT Article ID CAPILLARY-ZONE-ELECTROPHORESIS; TOTAL ANALYSIS SYSTEMS; LIQUID-CHROMATOGRAPHY; MICROCHIP ELECTROPHORESIS; GEL-ELECTROPHORESIS; HIGH-RESOLUTION; PEPTIDES; PERFORMANCE; TECHNOLOGY; GEOMETRIES AB High-efficiency, two-dimensional separations of tryptic digests were achieved using glass microfluidic devices. Following micellar electroldnetic chromatography (MEKC) separations in a 19.6-cm-long serpentine channel, the peptides were rapidly sampled into a 1.3-cm-long second-dimension channel, where they were separated by capillary electrophoresis (CE). The turns in the serpentine channel were asymmetrically tapered to minimize geometrical contributions to band broadening and to provide ample channel length for high-efficiency chromatographic separations. Analysis of rhodamine B injections routinely produced plate numbers of 230 000 and 40 000 in the first (MEKC) and second (CE) dimensions, respectively, corresponding to plate heights of 0.9 and 0.3 mum. The electric field strengths were 200 V/cm for MEKC and 2400 V/cm for CE. In analysis times less than 15 min, two-dimensional separation of bovine serum albumin tryptic digest produced a peak capacity of 4200 (110 in the first dimension and 38 in the second dimension). The system was used to identify a peptide from a tryptic digest of ovalbumin using standard addition and to distinguish between tryptic digests of human and bovine hemoglobin. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ramsey, JM (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. OI Culbertson, Christopher/0000-0002-6833-3237 FU NCI NIH HHS [R33CA83238] NR 39 TC 166 Z9 168 U1 1 U2 39 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 AUG 1 PY 2003 VL 75 IS 15 BP 3758 EP 3764 DI 10.1021/ac0264574 PG 7 WC Chemistry, Analytical SC Chemistry GA 709WV UT WOS:000184650300018 PM 14572041 ER PT J AU Twining, BS Baines, SB Fisher, NS Maser, J Vogt, S Jacobsen, C Tovar-Sanchez, A Sanudo-Wilhelmy, SA AF Twining, BS Baines, SB Fisher, NS Maser, J Vogt, S Jacobsen, C Tovar-Sanchez, A Sanudo-Wilhelmy, SA TI Quantifying trace elements in individual aquatic protist cells with a synchrotron X-ray fluorescence microprobe SO ANALYTICAL CHEMISTRY LA English DT Article ID MARINE-PHYTOPLANKTON; PARTICULATE MATTER; ZONE PLATES; IRON; METALS; LIMITATION; PLANKTON; NUTRIENT; DIATOMS; SAMPLES AB The study of trace metal cycling by aquatic protists is limited by current analytical techniques. Standard "bulk" element analysis techniques that rely on physical separations to concentrate cells for analysis cannot separate cells from co-occurring detrital material or other cells of differing taxonomy or trophic function. Here we demonstrate the ability of a synchrotron-based X-ray fluorescence (SXRF) microprobe to quantify the elements Si, Mn, Fe, Ni, and Zn in individual aquatic protist cells. 'Ibis technique distinguishes between different types of cells in an assemblage and between cells and other particulate matter. Under typical operating conditions, the minimum detection limits are 7.0 x 10(-16) mol mum(-2) for Si and between 5.0 x 10(-20) and 3.9 x 10(-19) mol mum(-2) for Mn, Fe, Ni, and Zn; this sensitivity is sufficient to detect these elements in cells from even the most pristine waters as demonstrated in phytoplankton cells collected from remote areas of the Southern Ocean. Replicate analyses of single cells produced variations of <5% for Si, Mn, Fe, and Zn and <10% for Ni. Comparative analyses of cultured phytoplankton cells generally show no significant differences in cellular metal concentrations measured with SXRF and standard bulk techniques (spectrophotometry and graphite furnace atomic absorption spectrometry). SXRF also produces two-dimensional maps of element distributions in cells, thereby providing information not available with other analytical approaches. This technique enables the accurate and precise measurement of trace metals in individual aquatic protists collected from natural environments. C1 SUNY Stony Brook, Marine Sci Res Ctr, Stony Brook, NY 11794 USA. SUNY Stony Brook, Ctr Environm Mol Sci, Stony Brook, NY 11794 USA. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Argonne Natl Lab, Adv Photon Source, Expt Facil Div, Argonne, IL 60439 USA. RP Twining, BS (reprint author), SUNY Stony Brook, Marine Sci Res Ctr, Stony Brook, NY 11794 USA. RI Tovar-Sanchez, Antonio/B-8003-2010; Maser, Jorg/K-6817-2013; Jacobsen, Chris/E-2827-2015; Vogt, Stefan/B-9547-2009; Vogt, Stefan/J-7937-2013; OI Tovar-Sanchez, Antonio/0000-0003-4375-1982; Jacobsen, Chris/0000-0001-8562-0353; Vogt, Stefan/0000-0002-8034-5513; Vogt, Stefan/0000-0002-8034-5513; Twining, Benjamin/0000-0002-1365-9192 NR 41 TC 131 Z9 137 U1 1 U2 34 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 AUG 1 PY 2003 VL 75 IS 15 BP 3806 EP 3816 DI 10.1021/ac034227z PG 11 WC Chemistry, Analytical SC Chemistry GA 709WV UT WOS:000184650300024 PM 14572047 ER PT J AU Zalk, DM AF Zalk, DM TI IOHA/ICOH Declaration on Occupational Hygiene SO ANNALS OF OCCUPATIONAL HYGIENE LA English DT Letter C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Zalk, DM (reprint author), Lawrence Livermore Natl Lab, POB 808,L-373, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0003-4878 J9 ANN OCCUP HYG JI Ann. Occup. Hyg. PD AUG PY 2003 VL 47 IS 6 BP 519 EP 519 DI 10.1093/annhyg/meg065 PG 1 WC Public, Environmental & Occupational Health; Toxicology SC Public, Environmental & Occupational Health; Toxicology GA 712LC UT WOS:000184798300009 PM 12931719 ER PT J AU Brim, H Venkateswaran, A Kostandarithes, HM Fredrickson, JK Daly, MJ AF Brim, H Venkateswaran, A Kostandarithes, HM Fredrickson, JK Daly, MJ TI Engineering Deinococcus geothermalis for bioremediation of high-temperature radioactive waste environments SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID EXTREMELY RADIATION-RESISTANT; DUPLICATION INSERTION; IONIZING-RADIATION; ESCHERICHIA-COLI; RADIODURANS R1; RECOMBINATION; DETERMINANTS; GENOME; REAGENT AB Deinococcus geothermalis is an extremely radiation-resistant thermophilic bacterium closely related to the mesophile Deinococcus radiodurans, which is being engineered for in situ bioremediation of radioactive wastes. We report that D. geothermalis is transformable with plasmids designed for D. radiodurans and have generated a Hg(II)-resistant D. geothermalis strain capable of reducing Hg(II) at elevated temperatures and in the presence of 50 Gy/h. Additionally, D. geothermalis is capable of reducing Fe(III)-nitrilotriacetic acid, U(VI), and Cr(VI). These characteristics support the prospective development of this thermophilic radiophile for bioremediation of radioactive mixed waste environments with temperatures as high as 55degreesC. C1 Uniformed Serv Univ Hlth Sci, Dept Pathol, Bethesda, MD 20814 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Daly, MJ (reprint author), Uniformed Serv Univ Hlth Sci, Dept Pathol, 4301 Jones Bridge Rd,Rm B3153, Bethesda, MD 20814 USA. NR 33 TC 56 Z9 60 U1 0 U2 13 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 AUG PY 2003 VL 69 IS 8 BP 4575 EP 4582 DI 10.1128/AEM.69.8.4575-4582.2003 PG 8 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 710GM UT WOS:000184672500032 PM 12902245 ER PT J AU Newby, DT Hadfield, TL Roberto, FF AF Newby, DT Hadfield, TL Roberto, FF TI Real-time PCR detection of Brucella abortus: a comparative study of SYBR green 1,5 '-exonuclease, and hybridization probe assays SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID POLYMERASE-CHAIN-REACTION; DNA AMPLIFICATION; GENUS BRUCELLA; AMOS PCR; DIFFERENTIATION; MELITENSIS; MILK; IDENTIFICATION; STRAINS; BLOOD AB Real-time PCR provides a means of detecting and quantifying DNA targets by monitoring PCR product accumulation during cycling as indicated by increased fluorescence. A number of different approaches can be used to generate the fluorescence signal. Three approaches-SYBR Green I (a double-stranded DNA intercalating dye), 5'-exonuclease (enzymatically released fluors), and hybridization probes (fluorescence resonance energy transfer)-were evaluated for use in a real-time PCR assay to detect Brucella abortus. The three assays utilized the same amplification primers to produce an identical amplicon. This amplicon spans a region of the B. abortus genome that includes portions of the alkB gene and the IS711 insertion element. All three assays were of comparable sensitivity, providing a linear assay over 7 orders of magnitude (from 7.5 ng down to 7.5 fg). However, the greatest specificity was achieved with the hybridization probe assay. C1 Idaho Natl Engn & Environm Lab, Dept Biotechnol, Idaho Falls, ID 83415 USA. Armed Forces Inst Pathol, Washington, DC 20306 USA. RP Newby, DT (reprint author), Idaho Natl Engn & Environm Lab, Dept Biotechnol, POB 1625, Idaho Falls, ID 83415 USA. NR 31 TC 57 Z9 63 U1 0 U2 5 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 AUG PY 2003 VL 69 IS 8 BP 4753 EP 4759 DI 10.1128/AEM.69.8.4753-4759.2003 PG 7 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 710GM UT WOS:000184672500055 PM 12902268 ER PT J AU Sebat, JL Colwell, FS Crawford, RL AF Sebat, JL Colwell, FS Crawford, RL TI Metagenomic profiling: Microarray analysis of an environmental genomic library SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID RIBOSOMAL-RNA GENES; SOIL DNA LIBRARIES; ESCHERICHIA-COLI; ALCALIGENES-EUTROPHUS; PCR; AMPLIFICATION; EXPRESSION; IDENTIFICATION; HYBRIDIZATION; PHOTOTROPHY AB Genomic libraries derived from environmental DNA (metagenomic libraries) are useful for characterizing uncultured microorganisms. However, conventional library-screening techniques permit characterization of relatively few environmental clones. Here we describe a novel approach for characterization of a metagenomic library by hybridizing the library with DNA from a set of groundwater isolates, reference strains, and communities. A cosmid library derived from a microcosm of groundwater microorganisms was used to construct a microarray (COSMO) containing similar to1-kb PCR products amplified from the inserts of 672 cosmids plus a set of 16S ribosomal DNA controls. COSMO was hybridized with Cy5-labeled genomic DNA from each bacterial strain, and the results were compared with the results for a common Cy3-labeled reference DNA sample consisting of a composite of genomic DNA from multiple species. The accuracy of the results was confirmed by the preferential hybridization of each strain to its corresponding rDNA probe. Cosmid clones were identified that hybridized specifically to each of 10 microcosm isolates, and other clones produced positive results with multiple related species, which is indicative of conserved genes. Many clones did not hybridize to any microcosm isolate; however, some of these clones hybridized to community genomic DNA, suggesting that they were derived from microbes that we failed to isolate in pure culture. Based on identification of genes by end sequencing of 17 such clones, DNA could be assigned to functions that have potential ecological importance, including hydrogen oxidation, nitrate reduction, and transposition. Metagenomic profiling offers an effective approach for rapidly characterizing many clones and identifying the clones corresponding to unidentified species of microorganisms. C1 Univ Idaho, Environm Res Inst, Moscow, ID 83844 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Crawford, RL (reprint author), Univ Idaho, Environm Res Inst, Moscow, ID 83844 USA. OI Sebat, Jonathan/0000-0002-9087-526X FU NCRR NIH HHS [P20 RR16454, P20 RR016454] NR 45 TC 88 Z9 109 U1 0 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 AUG PY 2003 VL 69 IS 8 BP 4927 EP 4934 DI 10.1128/AEM.69.8.4927-4934.2003 PG 8 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 710GM UT WOS:000184672500075 PM 12902288 ER PT J AU Engelhardt, I Finsterle, S AF Engelhardt, I Finsterle, S TI Thermal-hydraulic experiments with bentonite/crushed rock mixtures and estimation of effective parameters by inverse modeling SO APPLIED CLAY SCIENCE LA English DT Article; Proceedings Paper CT Workshop on Clay Microstructure CY OCT 15-17, 2002 CL LUND, SWEDEN DE bentonite; backfill; inverse modeling; specific heat; thermal conductivity AB The permeability and thermal conductivity of bentonite/crushed rock mixtures used as backfill for a nuclear waste repository have an important impact on the maximum radioactive load of the waste canister that can be embedded. Our research pursues useful methods for estimating the permeability, thermal conductivity, and specific heat of various bentonite/crushed rock mixtures for the conditions expected to prevail at the Aspo Hard Rock Laboratory (ASPO HRL). We conducted laboratory experiments and employed inverse modeling techniques to estimate effective thermal and hydraulic parameters suitable for predictive modeling of non-isothermal flow and transport from a nuclear waste repository. Thermal parameters are often calculated based on empirical relationships developed for homogeneous clays, i.e., they are not necessarily valid for mixtures. The applicability of these methods to model thermal-hydraulic processes within the bentonite/crushed rock mixtures in a deep repository needs to be assessed. All experiments were conducted with mixtures containing sodium- (SPV Volclay) or calcium-bentonite (Calcigel) and we used water from Aspo. Hydraulic column experiments were carried out with a specially designed permeameter and Darcy's law was applied to determine the hydraulic conductivity, which followed a lognormal distribution with mean values of 1.64 x 10(-11) and 4.93 x 10(-9) m/s for the two bentonite/crushed rock mixtures studied. The thermal laboratory experiments were analyzed using inverse modeling techniques. The simulated temperature distribution matched the measured data very well at all locations along the column and for all times. The inversely estimated thermal conductivity ranged from 1.6 to 2.2 W/mK, and the specific heat from 810 to 1020 J/kg K, both consistent with the predictions of the empirical relationships. However, the calculation of the effective parameters was very sensitive to heat loss through the insulation. The newly developed experimental setup in combination with inverse modeling allows the identification of key parameters governing the hydraulic and thermal processes of bentonite/crushed rock mixtures under repository conditions. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Fed Inst Geosci & Nat Resources, BGR, D-30655 Hannover, Germany. Univ Calif Berkeley, LBNL, Berkeley, CA 94720 USA. RP Engelhardt, I (reprint author), Fed Inst Geosci & Nat Resources, BGR, Stilleweg 2, D-30655 Hannover, Germany. RI Finsterle, Stefan/A-8360-2009 OI Finsterle, Stefan/0000-0002-4446-9906 NR 19 TC 13 Z9 15 U1 2 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-1317 J9 APPL CLAY SCI JI Appl. Clay Sci. PD AUG PY 2003 VL 23 IS 1-4 BP 111 EP 120 DI 10.1016/S0169-1317(03)00093-0 PG 10 WC Chemistry, Physical; Materials Science, Multidisciplinary; Mineralogy SC Chemistry; Materials Science; Mineralogy GA 735BX UT WOS:000186093500014 ER PT J AU Keegan, RP Gehrke, RJ AF Keegan, RP Gehrke, RJ TI A method to determine the time since last purification of weapons grade plutonium SO APPLIED RADIATION AND ISOTOPES LA English DT Article DE decay series; Pu-241; age determination; Bateman equations; weapons grade plutonium; non-destructive AB A non-destructive technique to determine the time since last purification of weapons grade plutonium based on the Pu-241 decay series has been developed and demonstrated to provide results that are consistent with our historical and process knowledge. This method is based or, the use of the Bateman equations and the decay chain Pu-241-->U-237 & Am-241-->Np-237-->Pa-233. Secular equilibrium is assumed between the (2.1 X 10(6) year) Np-237 and the (27 day) Pa-233. The proposed method is dependent upon the efficiency of the plutonium separation process but makes no assumption about the relative abundance of Pu-241 in Pu-239. Even though the technique was developed for weapons grade plutonium, it is expected to apply to almost any material that contains plutonium. (C) 2003 Elsevier Ltd. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Keegan, RP (reprint author), Idaho Natl Engn & Environm Lab, Mail Stop 2114,POB 1625, Idaho Falls, ID 83415 USA. NR 5 TC 14 Z9 15 U1 0 U2 6 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 AUG-SEP PY 2003 VL 59 IS 2-3 BP 137 EP 143 DI 10.1016/S0969-8043(03)00149-0 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 720RB UT WOS:000185272800007 PM 12941503 ER PT J AU Shores, EF Mueller, GE Schlapper, GA AF Shores, EF Mueller, GE Schlapper, GA TI A new Be-9(alpha,n) cross-section evaluation for use in the SOURCES computer code SO APPLIED RADIATION AND ISOTOPES LA English DT Article DE beryllium; breakup reaction; alpha decay; neutron production; branching fraction ID NEUTRON-SPECTRUM; ALPHA-PARTICLES; N) SOURCE; CM-242-BE; AVERAGE AB Experimental breakup reaction data was the basis for choosing a set of alpha optical potential parameters for calculating the cross section from the Be-9(alpha, alpha'n) reaction with the GNASH code. Although not in complete agreement with experimental values, the promising results suggest additional work and continued research for optimal parameters. Accommodating modifications in the SOURCES code system required improved data and an approximation for the three-body reaction branching fractions is presented as a temporary solution. Experimental spectra from AcBe, CmBe, and simulated AmBe neutron sources are compared to SOURCES calculations using the new branching fractions and serve as benchmarks for this new version of the code. (C) 2003 Elsevier Ltd. All rights reserved. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Missouri, Dept Nucl Engn, Rolla, MO 65401 USA. Natl Nucl Secur Adm, Los Alamos Site Off, Los Alamos, NM 87544 USA. RP Shores, EF (reprint author), Los Alamos Natl Lab, Mail Stop K483, Los Alamos, NM 87545 USA. OI Mueller, Gary/0000-0001-5963-9026 NR 27 TC 1 Z9 2 U1 1 U2 1 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 AUG-SEP PY 2003 VL 59 IS 2-3 BP 151 EP 158 DI 10.1016/S0969-8043(03)00157-X 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 720RB UT WOS:000185272800009 PM 12941505 ER PT J AU Thompson, SE Foster, NS Johnson, TJ Valentine, NB Amonette, JE AF Thompson, SE Foster, NS Johnson, TJ Valentine, NB Amonette, JE TI Identification of bacterial spores using statistical analysis of Fourier transform infrared photoacoustic spectroscopy data SO APPLIED SPECTROSCOPY LA English DT Article DE spores; photoacoustic; Fourier transform infrared spectroscopy; FT-IR; bacteria; bacillus; classification and regression trees; CART; spectroscopy; statistical analysis ID ARTIFICIAL NEURAL-NETWORKS; FLIGHT MASS-SPECTROMETRY; RESONANCE RAMAN-SPECTRA; FT-IR SPECTROSCOPY; BACILLUS-SUBTILIS; RAPID IDENTIFICATION; BIOLOGICAL WEAPONS; AIRBORNE BIOSENSOR; AGENT-DETECTION; FIELD DETECTION AB Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) has been applied for the first time to the identification and speciation of bacterial spores. A total of forty specimens representing five strains of Bacillus spores (Bacillus subtilis ATCC 49760, Bacillus atrophaeus ATCC 49337, Bacillus subtilis 6051, Bacillus thuringiensis subsp. kurstaki, and Bacillus globigii Dugway) were analyzed. Spores were deposited, with minimal preparation, into the photoacoustic sample cup and their spectra recorded. Principal component analysis (PCA), classification and regression trees (CART), and Mahalanobis distance calculations were used on this spectral library to develop algorithms for step-wise classification at three levels: (1) bacterial/nonbacterial, (2) membership within the spore library, and (3) bacterial strain. Internal cross-validation studies on library spectra yielded classification success rates of 87% or better at each of these three levels. Analysis of fifteen blind samples, which included five samples of spores already in the spectral library, two samples of closely related Bacillus globigii 01 spores not in the library, and eight samples of nonbacterial materials, yielded 100% accuracy in distinguishing among bacterial/nonbacterial samples, membership in the library, and bacterial strains within the library. Index Headings: Spores; Photoacoustic; Fourier transform infrared spectroscopy; FT-IR; Bacteria; Bacillus; Classification and regression trees; CART; Spectroscopy; Statistical analysis. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, POB 999,MS K8-96, Richland, WA 99352 USA. EM nancy.foster@pnl.gov NR 77 TC 42 Z9 42 U1 0 U2 14 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0003-7028 EI 1943-3530 J9 APPL SPECTROSC JI Appl. Spectrosc. PD AUG PY 2003 VL 57 IS 8 BP 893 EP 899 DI 10.1366/000370203322258832 PG 7 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 709ZE UT WOS:000184655800001 PM 14661830 ER PT J AU Bryan, AL Hopkins, WA Baionno, JA Jackson, BP AF Bryan, AL Hopkins, WA Baionno, JA Jackson, BP TI Maternal transfer of contaminants to eggs in common grackles (Quiscalus quiscala) nesting on coal fly ash basins SO ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY LA English DT Article ID TRACE-ELEMENT CONCENTRATIONS; STANDARD METABOLIC-RATE; COMBUSTION WASTE; BROOD REDUCTION; SELENIUM; REPRODUCTION; TOXICITY; BIRDS; DEPOSITION; RESIDUES AB Coal combustion is a major source of trace elements to the environment. Aquatic disposal of wastes from this process can result in reproductive failure in many wildlife species, but little is known regarding impacts on avian fauna. Individual eggs were collected from common grackles (Quiscalus quiscala) nesting in association with coal fly ash settling basins and a reference site to determine if females from the contaminated site transfered trace elements to their eggs. Whole clutches were also collected from both sites to examine inter- and intra-clutch variability of maternally transferred contaminants. Selenium was the only trace element found in significantly higher concentrations in ash basin eggs ((x) over bar = 5.88 +/- 0.44 mug/g DW) than in reference eggs ((x) over bar = 2.69 +/- 0.13 mug/g DW). Selenium concentrations in eggs from the ash basins were above background levels, but did not exceed higher proposed Se toxicity thresholds. Inter- and intra-clutch variation was higher for ash basin clutches than reference clutches. The relationship between selenium concentrations and laying order (estimated by egg mass) was not statistically significant, but increased Se concentration in the second egg of most ash basin clutches followed by declining concentrations in subsequent eggs suggested that further examination of this pattern might be warranted. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Bryan, AL (reprint author), Univ Georgia, Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. NR 29 TC 21 Z9 21 U1 2 U2 8 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0090-4341 J9 ARCH ENVIRON CON TOX JI Arch. Environ. Contam. Toxicol. PD AUG PY 2003 VL 45 IS 2 BP 273 EP 277 DI 10.1007/s00244-002-0212-9 PG 5 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 703QC UT WOS:000184291600016 PM 14565586 ER PT J AU Dieckmann, J Roth, KW Brodrick, J AF Dieckmann, J Roth, KW Brodrick, J TI Air-to-air energy recovery heat exchangers SO ASHRAE JOURNAL LA English DT Article AB This is the sixth article covering a new energy-saving technology evaluated in a recent U.S. Department of Energy report, which is available at iwww.eren.doe.gov/buildings/documents. C1 TIAX, HVAC & Refrigerat Technol Sector, Cambridge, MA USA. TIAX, Appliance & Bldg Technol Sector, Cambridge, MA USA. US DOE, Bldg Technol Program, Washington, DC USA. RP Dieckmann, J (reprint author), TIAX, HVAC & Refrigerat Technol Sector, Cambridge, MA USA. NR 2 TC 17 Z9 18 U1 1 U2 3 PU AMER SOC HEATING REFRIGERATING AIR-CONDITIONING ENG, INC, PI ATLANTA PA 1791 TULLIE CIRCLE NE, ATLANTA, GA 30329 USA SN 0001-2491 EI 1943-6637 J9 ASHRAE J JI ASHRAE J. PD AUG PY 2003 VL 45 IS 8 BP 57 EP 58 PG 2 WC Thermodynamics; Construction & Building Technology; Engineering, Mechanical SC Thermodynamics; Construction & Building Technology; Engineering GA 708TV UT WOS:000184586200019 ER PT J AU Inada, N Becker, RH Burles, S Castander, FJ Eisenstein, D Hall, PB Johnston, DE Pindor, B Richards, GT Schechter, PL Sekiguchi, M White, RL Brinkmann, J Frieman, JA Kleinman, SJ Krzesinski, J Long, DC Neilsn, EH Newman, PR Nitta, A Schneider, DP Snedden, S York, DG AF Inada, N Becker, RH Burles, S Castander, FJ Eisenstein, D Hall, PB Johnston, DE Pindor, B Richards, GT Schechter, PL Sekiguchi, M White, RL Brinkmann, J Frieman, JA Kleinman, SJ Krzesinski, J Long, DC Neilsn, EH Newman, PR Nitta, A Schneider, DP Snedden, S York, DG TI SDSS J092455.87+021924.9: An interesting gravitationally lensed quasar from the Sloan Digital Sky Survey SO ASTRONOMICAL JOURNAL LA English DT Article DE gravitational lensing; quasars : individual (SDSS J092455.87+021924.9) ID EARLY DATA RELEASE; COSMOLOGICAL CONSTANT; CROSS-SECTIONS; DARK-MATTER; GALAXIES; DISTRIBUTIONS; SUBSTRUCTURE; VARIABILITY; STATISTICS; SELECTION AB We report the discovery of a new gravitationally lensed quasar from the Sloan Digital Sky Survey, SDSS J092455.87+021924.9 (SDSS J0924+0219). This object was selected from among known SDSS quasars by an algorithm that was designed to select another known SDSS lensed quasar (SDSS J1226-0006A,B). Five separate components, three of which are unresolved, are identified in photometric follow-up observations obtained with the Magellan Consortium's 6.5 m Walter Baade Telescope at Las Campanas Observatory. Two of the unresolved components (designated A and B) are confirmed to be quasars with z = 1.524; the velocity difference is less than 100 km s(-1) according to spectra taken with the W. M. Keck Observatory's Keck II Telescope at Mauna Kea, Hawaii. A third stellar component, designated C, has the colors of a quasar with redshift similar to components A and B. The maximum separation of the point sources is 1."78. The other two sources, designated G and D, are resolved. Component G appears to be the best candidate for the lensing galaxy. Although component D is near the expected position of the fourth lensed component in a four-image lens system, its properties are not consistent with being the image of a quasar at z similar to 1.5. Nevertheless, the identical redshifts of components A and B and the presence of component C strongly suggest that this object is a gravitational lens. Our observations support the idea that a foreground object reddens the fourth lensed component and that another unmodeled effect (such as micro- or millilensing) demagnifies it, but we cannot rule out the possibility that SDSS J0924+0219 is an example of the relatively rare class of "three-component'' lens systems. C1 Univ Tokyo, Inst Cosm Ray Res, Kashiwa, Chiba 2778582, Japan. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. Univ Chile, Dept Astron, Santiago, Chile. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Santiago 22, Chile. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Inst Adv Study, Princeton, NJ 08540 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Apache Point Observ, Sunspot, NM 88349 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Akad Pedag Krakowie, Obserwatorium Astron Suhorze, PL-30084 Krakow, Poland. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Inada, N (reprint author), Univ Tokyo, Inst Cosm Ray Res, 5-1-5 Kashiwa, Kashiwa, Chiba 2778582, Japan. OI PINDOR, BARTOSZ/0000-0003-3240-2437 NR 39 TC 60 Z9 60 U1 0 U2 3 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 AUG PY 2003 VL 126 IS 2 BP 666 EP 674 DI 10.1086/375906 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 706GU UT WOS:000184446600005 ER PT J AU Morgan, ND Gregg, MD Wisotzki, L Becker, R Maza, J Schechter, PL White, RL AF Morgan, ND Gregg, MD Wisotzki, L Becker, R Maza, J Schechter, PL White, RL TI CTQ 327: A new gravitational lens SO ASTRONOMICAL JOURNAL LA English DT Article DE gravitational lensing; quasars : individual (CTQ 327) ID HUBBLE-SPACE-TELESCOPE; EARLY-TYPE GALAXIES; DIGITAL SKY SURVEY; COSMOLOGICAL CONSTANT; IMAGING SPECTROGRAPH; FUNDAMENTAL PLANE; BRIGHT QSOS; PHOTOMETRY; STARS; PERFORMANCE AB We present the second gravitationally lensed quasar discovered during the course of a Hubble Space Telescope Space Telescope Imaging Spectrograph snapshot survey for small-separation gravitational lenses. CTQ 327 is a double quasar with an image separation of 1."22 and a g-band flux ratio of roughly 5 to 1. Spectra reveal both components to be z = 1.37 quasars, and the lensing galaxy is clearly visible after point-spread function subtraction of the two quasar components. The light pro. le of the lensing galaxy is well modeled by an r(1/4) law, indicative of an early-type elliptical galaxy. An estimate of the lens galaxy redshift is z similar to 0.4-0.6, based on the Faber-Jackson relationship and photometric considerations, although values outside this range are still consistent with the present data. Resolved spectra of the two quasars show similar, but not identical, continuum and emission-line features.component A exhibits weaker emission lines with respect to the continuum than does component B, and there is evidence of intrinsic differences in the emission-line profiles between the two components. Optical monitoring of the quasar pair also shows a change in the g-band flux ratio of 0.14 mag over a 3 month period. These spectral and photometric differences may be due to microlensing fluctuations from stars in the lensing galaxy, intrinsic quasar variability coupled with the system's differential time delay, or some combination of the two. The observed variability makes CTQ 327 an attractive target for future flux monitoring, aimed at time-delay or microlensing studies. C1 Yale Univ, Ctr Astron & Astrophys, New Haven, CT 06520 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Astrophys Inst Potsdam, D-14482 Potsdam, Germany. Univ Chile, Dept Astron, Santiago, Chile. MIT, Dept Phys, Cambridge, MA 02139 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. RP Morgan, ND (reprint author), Yale Univ, Ctr Astron & Astrophys, New Haven, CT 06520 USA. EM nicholas.morgan@yale.edu; gregg@igpp.llnl.gov; lutz@aip.de; bob@igpp.llnl.gov; jmaza@das.uchile.cl; schech@space.mit.edu; rlw@stsci.edu RI White, Richard/A-8143-2012; Maza, Jose/I-5722-2016 OI Maza, Jose/0000-0003-2068-1328 NR 43 TC 14 Z9 14 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD AUG PY 2003 VL 126 IS 2 BP 696 EP 705 DI 10.1086/376470 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 706GU UT WOS:000184446600008 ER PT J AU White, RL Helfand, DJ Becker, RH Gregg, MD Postman, M Lauer, TR Oegerle, W AF White, RL Helfand, DJ Becker, RH Gregg, MD Postman, M Lauer, TR Oegerle, W TI An I-band-selected sample of radio-emitting quasars: Evidence for a large population of red quasars SO ASTRONOMICAL JOURNAL LA English DT Article DE catalogs; galaxies : clusters : general; quasars : general; surveys ID QSO REDSHIFT SURVEY; DIGITAL SKY SURVEY; 1ST SURVEY; REDDEST QUASARS; SOURCE CATALOG; SPECTRA; IDENTIFICATIONS; ENVIRONMENTS; EXTINCTION; DISCOVERY AB We have constructed a sample of quasar candidates by comparing the FIRST radio survey with the 16 deg(2) Deeprange I-band survey carried out by Postman and coworkers. Spectroscopic follow-up of this magnitude-limited sample [I < 20.5, F-v (20 cm) > 1 mJy] has revealed 35 quasars, all but two of which are reported here for the first time. This sample contains some unusual broad absorption line (BAL) quasars, including the first radio-loud FR II BAL previously reported by Gregg and coworkers. Comparison of this sample with the FIRST Bright Quasar survey samples selected in a somewhat bluer band and with brighter magnitude limits reveals that the I-band-selected sample is redder by 0.25-0.5 mag in B-R and that the color difference is not explained by the higher mean redshift of this sample but must be intrinsic. Our small sample contains five quasars with unusually red colors, including three that appear very heavily reddened. Our data are fitted well with normal blue quasar spectra attenuated by more than 2.5 mag of extinction in the I band. These red quasars are only seen at low redshifts (z < 1.3). Even with a magnitude limit I < 20.5, our survey is deep enough to detect only the most luminous of these red quasars at z less than or similar to 1; similar objects at higher redshifts would fall below our I- band limit. Indeed, the five most luminous objects (using dereddened magnitudes) with z < 1.3 are all red. Our data strongly support the hypothesis that radio quasars are dominated by a previously undetected population of red, heavily obscured objects. Unless highly reddened quasars are preferentially also highly luminous, there must be an even larger, as yet undiscovered, population of red quasars at lower luminosity. We are likely to be finding only the most luminous tip of the red quasar iceberg. A comparison of the positions of the objects in our sample with the catalog of Deeprange cluster candidates reveals that five of our six z < 1 quasars are associated with cluster candidates of similar estimated redshifts. This association is very unlikely to be the result of chance. It has some surprising implications, including the possibility that up to half of the Deeprange clusters at z similar to 1 have associated quasars. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Columbia Univ, Dept Astron, New York, NY 10027 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. Natl Opt Astron Observ, Tucson, AZ 85726 USA. NASA, Astron & Solar Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP White, RL (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. RI Oegerle, William/C-9070-2012; OI Postman, Marc/0000-0002-9365-7989 NR 51 TC 45 Z9 45 U1 0 U2 1 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 AUG PY 2003 VL 126 IS 2 BP 706 EP 722 DI 10.1086/376597 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 706GU UT WOS:000184446600009 ER PT J AU Harris, HC Liebert, J Kleinman, SJ Nitta, A Anderson, SF Knapp, GR Krzesinski, J Schmidt, G Strauss, MA Berk, DV Eisenstein, D Hawley, S Margon, B Munn, JA Silvestri, NM Smith, JA Szkody, P Collinge, MJ Dahn, CC Fan, XH Hall, PB Schneider, DP Brinkmann, J Burles, S Gunn, JE Hennessy, GS Hindsley, R Ivezic, Z Kent, S Lamb, DQ Lupton, RH Nichol, RC Pier, JR Schlegel, DJ SubbaRao, M Uomoto, A Yanny, B York, DG AF Harris, HC Liebert, J Kleinman, SJ Nitta, A Anderson, SF Knapp, GR Krzesinski, J Schmidt, G Strauss, MA Berk, DV Eisenstein, D Hawley, S Margon, B Munn, JA Silvestri, NM Smith, JA Szkody, P Collinge, MJ Dahn, CC Fan, XH Hall, PB Schneider, DP Brinkmann, J Burles, S Gunn, JE Hennessy, GS Hindsley, R Ivezic, Z Kent, S Lamb, DQ Lupton, RH Nichol, RC Pier, JR Schlegel, DJ SubbaRao, M Uomoto, A Yanny, B York, DG TI An initial survey of white dwarfs in the Sloan Digital Sky Survey SO ASTRONOMICAL JOURNAL LA English DT Article DE stars : chemically peculiar; stars : magnetic fields; surveys; white dwarfs ID EARLY DATA RELEASE; HAMBURG/ESO SURVEY; STELLAR OBJECTS; HYDROGEN-RICH; STARS; SYSTEM; SPECTRA; DISCOVERY; CATALOG; CARBON AB An initial assessment is made of white dwarf and hot subdwarf stars observed in the Sloan Digital Sky Survey. In a small area of sky ( 190 square degrees), observed much like the full survey will be, 269 white dwarfs (WDs) and 56 hot subdwarfs are identified spectroscopically where only 44 white dwarfs and five hot subdwarfs were known previously. Most are ordinary DA ( hydrogen atmosphere) and DB ( helium) types. In addition, in the full survey to date, a number of WDs have been found with uncommon spectral types. Among these are blue DQ stars displaying lines of atomic carbon; red DQ stars showing molecular bands of C-2 with a wide variety of strengths; DZ stars where Ca and occasionally Mg, Na, and/or Fe lines are detected; and magnetic WDs with a wide range of magnetic field strengths in DA, DB, DQ, and ( probably) DZ spectral types. Photometry alone allows identification of stars hotter than 12,000 K, and the density of these stars for 15 < g < 20 is found to be similar to2.2 deg(-2) at Galactic latitudes of 29degrees - 62degrees. Spectra are obtained for roughly half of these hot stars. The spectra show that for 15 < g < 17, 40% of hot stars are WDs, and the fraction of WDs rises to similar to90% at g = 20. The remainder are hot sdB and sdO stars. C1 USN Observ, Flagstaff, AZ 86002 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Apache Point Observ, Sunspot, NM 88349 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Obserwatorium Astron Suhorze, Akad Pedag Krakowie, PL-30084 Krakow, Poland. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. Pontificia Univ Catolica Chile, Fac Fis, Dept Astron & Astrofis, Santiago 22, Chile. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. USN Observ, Washington, DC 20392 USA. USN, Res Lab, Remote Sensing Div, Washington, DC 20375 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15232 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Harris, HC (reprint author), USN Observ, POB 1149, Flagstaff, AZ 86002 USA. RI Margon, Bruce/B-5913-2012 NR 67 TC 72 Z9 72 U1 0 U2 2 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 AUG PY 2003 VL 126 IS 2 BP 1023 EP 1040 DI 10.1086/376842 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 706GU UT WOS:000184446600034 ER PT J AU Kaufl, HU Koller, J Kerber, F AF Kaufl, HU Koller, J Kerber, F TI The evolution of V4334 Sgr (Sakurai's object) in the Mid-Infrared SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE stars : AGB and post-AGB; stars : evolution; circumstellar matter; planetary nebulae : individual : Sakurai's Object (V4334 Sgr) ID FINAL HELIUM FLASH; INTERSTELLAR GRAINS; DUST; STAR; SHELL; SGR AB Since Sakurai's object (V4334 Sgr) underwent a late helium flash in 1995, its fast evolution has been monitored with great effort. We present TIMMI and TIMMI 2 photometric observations covering a spectral range from 5 to 20 mum with a total of 8 filters. We found drastic changes in the spectral energy distribution indicating a drop of temperature in the dust envelope from 1000 to 600 K in half a year only. Combined with optical observations reported elsewhere, we conclude that the phase of dust formation has probably stopped in mid-2001 and that the dusty envelope has been expanding only, ever since. An expansion velocity of about 1000 km s(-1) is required to explain the rapid cooling. Other optical and near-infrared observations support the existence of such high velocity flows in the envelope of V4334 Sgr. An estimate for the bolometric luminosity of approximate to 2000 L-. is derived for a distance of 1 kpc. Taking into account theoretical models a distance of 2 +/- 1 kpc to V4334 Sgr is suggested. As a consequence of its fast final helium flash evolution, Sakurai's object may start to destroy its surrounding dust in the not too distant future. C1 European So Observ, D-85748 Garching, Germany. Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Space Telescope European Coordinating Facil, D-85748 Garching, Germany. RP Kaufl, HU (reprint author), European So Observ, Karl Schwarzschild Str 2, D-85748 Garching, Germany. RI Koller, Josef/C-5591-2009 OI Koller, Josef/0000-0002-6770-4980 NR 36 TC 7 Z9 7 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD AUG PY 2003 VL 406 IS 3 BP 981 EP 985 DI 10.1051/0004-6361:20030828 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 704BL UT WOS:000184317800022 ER PT J AU Reuland, M van Breugel, W Rottgering, H de Vries, W Stanford, SA Dey, A Lacy, M Bland-Hawthorn, J Dopita, M Miley, G AF Reuland, M van Breugel, W Rottgering, H de Vries, W Stanford, SA Dey, A Lacy, M Bland-Hawthorn, J Dopita, M Miley, G TI Giant Ly alpha nebulae associated with high-redshift radio galaxies SO ASTROPHYSICAL JOURNAL LA English DT Review DE galaxies : formation; galaxies : high-redshift; quasars : emission lines; stars : formation ID EMISSION-LINE GAS; JET-CLOUD INTERACTIONS; 4C 41.17; STAR-FORMATION; INFRARED OBSERVATIONS; DEEP SPECTROSCOPY; GALACTIC SUPERWINDS; COOLING RADIATION; FORMING GALAXIES; PROTO-CLUSTER AB We report deep, Keck narrowband Lyalpha images of the luminous z > 3 radio galaxies 4C 41.17, 4C 60.07, and B2 0902+ 34. The images show giant, 100 - 200 kpc scale, emission-line nebulae, centered on these galaxies, that exhibit a wealth of morphological structure, including extended low surface brightness emission in the outer regions, radially directed. laments, cone-shaped structures and ( indirect) evidence for extended Lyalpha absorption. We discuss these features within a general scenario in which the nebular gas cools gravitationally in large cold dark matter halos, forming stars and multiple stellar systems. Merging of these "building blocks'' triggers large-scale starbursts, forming the stellar bulges of massive radio galaxy hosts, and feeds supermassive black holes, which produce the powerful radio jets and lobes. The radio sources, starburst superwinds, and radiation pressure from active galactic nucleus then disrupt the accretion process, limiting galaxy and black hole growth, and imprint the observed. lamentary and cone-shaped structures of the Lyalpha nebulae. C1 Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. Leiden Observ, NL-2300 RA Leiden, Netherlands. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Kitt Peak Natl Observ, Natl Opt Astron Observ, Tucson, AZ 85726 USA. CALTECH, SIRTF Sci Ctr, Pasadena, CA 91125 USA. Anglo Australian Observ, Epping, NSW 2121, Australia. Australian Natl Univ, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. RP Reuland, M (reprint author), Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, L-413,POB 808, Livermore, CA 94551 USA. RI Dopita, Michael/P-5413-2014 OI Dopita, Michael/0000-0003-0922-4986 NR 102 TC 98 Z9 99 U1 0 U2 1 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 AUG 1 PY 2003 VL 592 IS 2 BP 755 EP 766 DI 10.1086/375619 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 705RG UT WOS:000184408100009 ER PT J AU Salmonson, JD AF Salmonson, JD TI Perspective on afterglows: Numerically computed views, light curves, and the analysis of homogeneous and structured jets with lateral expansion SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; gamma rays : theory ID GAMMA-RAY BURSTS; CONTINUOUS ENERGY INJECTION; RELATIVISTIC JETS; PARAMETERS; SIGNATURE; RESERVOIR; DYNAMICS; EMISSION; SPECTRA; ANGLE AB Herein I present numerical calculations of light curves of homogeneous and structured afterglows with various lateral expansion rates as seen from any vantage point. Such calculations allow for direct simulation of observable quantities for complex afterglows with arbitrary energy distributions and lateral expansion paradigms. A simple, causal model is suggested for lateral expansion of the jet as it evolves: namely, that the lateral expansion kinetic energy derives from the forward kinetic energy. As such, the homogeneous jet model shows that lateral expansion is important at all times in the afterglow evolution and that analytical scaling laws do a poor job at describing the afterglow decay before and after the break. In particular, I find that lateral expansion does not cause a break in the light curve as had been predicted. A primary purpose of this paper is to study structured afterglows, which do a good job of reproducing global relationships and correlations in the data and thus suggest the possibility of a universal afterglow model. Simulations of structured jets show a general trend in which jet breaks become more pronounced with increasing viewing angle with respect to the jet axis. In fact, under certain conditions a bump can occur in the light curve at the jet-break time. I derive scaling relations for this bump and suggest that it may be a source of some bumps in observed light curves such as that of GRB 000301C. A couple of lateral expansion models are tested over a range of efficiencies and viewing angles, and it is found that lateral expansion can, in some cases, substantially sharpen the jet break. I show flux surface contour maps and simulated images of the afterglows that give insight into how they evolve and determine their light curves. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Salmonson, JD (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 30 TC 35 Z9 35 U1 0 U2 1 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 AUG 1 PY 2003 VL 592 IS 2 BP 1002 EP 1017 DI 10.1086/375580 PN 1 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 705RG UT WOS:000184408100027 ER PT J AU Sion, EM Gansicke, BT Long, KS Szkody, P Cheng, FH Howell, SB Godon, P Welsh, WF Starrfield, S Knigge, C Sparks, WM AF Sion, EM Gansicke, BT Long, KS Szkody, P Cheng, FH Howell, SB Godon, P Welsh, WF Starrfield, S Knigge, C Sparks, WM TI Hubble Space Telescope Spectroscopy of the unexpected 2001 July outburst of the dwarf nova WZ Sagittae SO ASTROPHYSICAL JOURNAL LA English DT Article DE novae, cataclysmic variables; stars : individual (WZ Sagittae); white dwarfs ID VW HYDRI; ACCRETION DISK; FOS SPECTROSCOPY; WHITE-DWARF; SUPEROUTBURST; QUIESCENCE; ATMOSPHERES; STAR AB We present Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph E140M spectra of the dwarf nova WZ Sge, following the early superoutburst of 2001 July. Our four far-ultraviolet (FUV) spectra, obtained over a time span of 4 months, monitor changes in the hot component of the system during the decline phase. The spectra cover the wavelength interval 1150-1708 Angstrom. They reveal Stark-broadened Lyalpha and He II (1640) absorption and absorption lines due to metals (Si, C, N, Al) from a range of ionization states. Single-temperature white dwarf models provide reasonable qualitative agreement with the HST spectra. We find that the white dwarf appears to dominate the spectra from October through December. However, it is not clear that the absorption lines of metals form in the white dwarf photosphere. Therefore, the derived abundances and rotational velocity must be viewed with caution. Only a modest improvement in the fits to the data results when an accretion belt component is included. If the FUV spectra arise from the white dwarf alone, then we measure a cooling in response to the outburst of at least 11,000 K (29,000-18,000 K). The absence of broad underlying absorption features due to metals at this stage suggests slow rotation (similar to200 km s(-1)). It is possible that the white dwarf envelope has expanded due to the heating by the outburst or that the relatively narrow absorption features we observe are forming in an inflated disk atmosphere or curtain associated with the outburst. C1 Villanova Univ, Dept Astron & Astrophys, Villanova, PA 19085 USA. Univ Southampton, Dept Phys & Astron, Southampton SO17 1BJ, Hants, England. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Univ Sci & Technol China, Ctr Astrophys, Hefei 230026, Anhui, Peoples R China. Univ Calif Riverside, Dept Geophys & Planetary Phys, Riverside, CA 92521 USA. San Diego State Univ, Dept Astron, San Diego, CA 92182 USA. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. Los Alamos Natl Lab, XNH, Los Alamos, NM 87545 USA. RP Sion, EM (reprint author), Villanova Univ, Dept Astron & Astrophys, 800 Lancaster Ave, Villanova, PA 19085 USA. RI Gaensicke, Boris/A-9421-2012 OI Gaensicke, Boris/0000-0002-2761-3005 NR 23 TC 19 Z9 19 U1 0 U2 2 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 AUG 1 PY 2003 VL 592 IS 2 BP 1137 EP 1150 DI 10.1086/375855 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 705RG UT WOS:000184408100039 ER PT J AU Erskine, DJ Edelstein, J Feuerstein, WM Welsh, B AF Erskine, DJ Edelstein, J Feuerstein, WM Welsh, B TI High-resolution broadband spectroscopy using an externally dispersed interferometer SO ASTROPHYSICAL JOURNAL LA English DT Article DE instrumentation : interferometers; instrumentation : spectrographs; techniques : interferometric ID RADIAL VELOCIMETRY; SPECTROMETER AB An externally dispersed interferometer (EDI) is a series combination of a fixed delay interferometer and an external grating spectrograph. We describe how the EDI can boost the effective resolving power of an echelle or linear grating spectrograph by a factor of 2 - 3 or more over the spectrograph's full bandwidth. The interferometer produces spectral fringes over the entire spectrograph's bandwidth. The fringes heterodyne with spectral features to provide a low spatial frequency moire pattern. The heterodyning is numerically reversed to recover highly detailed spectral information unattainable by the spectrograph alone. We demonstrate resolution boosting for stellar and solar measurements of two-dimensional echelle and linear grating spectra. An effective spectral resolution of similar to 100,000 has been obtained from the similar to 50,000 resolution Lick Observatory two-dimensional echelle spectrograph, and that of similar to 50,000 from an similar to 20,000 resolution linear grating spectrograph. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RP Erskine, DJ (reprint author), Lawrence Livermore Natl Lab, Mail Stop L-479, Livermore, CA 94550 USA. NR 14 TC 22 Z9 23 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 AUG 1 PY 2003 VL 592 IS 2 BP L103 EP L106 DI 10.1086/377703 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 705RJ UT WOS:000184408300013 ER PT J AU Savin, DW Kahn, SM Gwinner, G Grieser, M Repnow, R Saathoff, G Schwalm, D Wolf, A Muller, A Schippers, D Zavodszky, PA Chen, MH Gorczyca, TW Zatsarinny, O Gu, MF AF Savin, DW Kahn, SM Gwinner, G Grieser, M Repnow, R Saathoff, G Schwalm, D Wolf, A Muller, A Schippers, D Zavodszky, PA Chen, MH Gorczyca, TW Zatsarinny, O Gu, MF TI Dielectronic recombination of Fe XXI and Fe XXII via N=2 -> N '=2 core excitations SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE atomic data; atomic processes; methods : laboratory ID HIGH-RESOLUTION MEASUREMENT; LABORATORY MEASUREMENTS; IONIZATION EQUILIBRIUM; THEORETICAL CALCULATIONS; PHOTOIONIZED GAS; IONS; COEFFICIENTS; XVIII; RATES; XIX AB We have measured dielectronic recombination (DR) resonance strengths and energies for carbon-like Fe XXI forming Fe XX and for boron-like Fe XXII forming Fe XXI via N = 2 --> N' = 2 core excitations. All measurements were carried out using the heavy-ion Test Storage Ring at the Max-Planck-Institute for Nuclear Physics in Heidelberg, Germany. We have also calculated these resonance strengths and energies using three independent, state-of-the-art perturbative techniques: a multiconfiguration Breit-Pauli (MCBP) method using the code AUTOSTRUCTURE, a multiconfiguration Dirac-Fock (MCDF) method, and a relativistic configuration interaction method using the Flexible Atomic Code (FAC). Overall, reasonable agreement is found between our experimental results and our theoretical calculations. The most notable discrepancies tend to occur for relative collision energies less than or similar to 3 eV. We have used our measured 2 --> 2 results to produce Maxwellian-averaged rate coefficients for Fe XXI and Fe XXII. Our experimentally derived rate coefficients are estimated to be accurate to better than approximate to 20% both for Fe XXI at k(B)T(e) > 0.5 eV and for Fe XXII at k(B)T(e) > 0.001 eV. For these results, we provide fits that are accurate to better than 0.5% for Fe XXI at 0.001 eV less than or equal to k(B)T(e) less than or equal to 10, 000 eV and for Fe XXII at 0.02 eV less than or similar to k(B)T(e) less than or equal to 10, 000 eV. Our fitted rate coefficients are suitable for ionization balance calculations involving Fe XXI and Fe XXII in photoionized plasmas. Previous published Burgess formula and LS-coupling calculations are in poor agreement with our experimentally derived rate coefficients. None of these published calculations reliably reproduce the magnitude or temperature dependence of our experimental results. Our previously published Fe XXI MCDF results are in good agreement with our experimental results for k(B)T(e) greater than or similar to 0.07 eV. For both ions in this temperature range our new MCBP, MCDF, and FAC results are in excellent agreement with our experimentally derived rate coefficient. C1 Columbia Univ, Astrophys Lab, New York, NY 10027 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. Max Planck Inst Kernphys, D-69117 Heidelberg, Germany. Univ Giessen, Inst Kernphys, D-35392 Giessen, Germany. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. MIT, Ctr Space Res, Cambridge, MA 02139 USA. RP Savin, DW (reprint author), Columbia Univ, Astrophys Lab, New York, NY 10027 USA. RI Saathoff, Guido/B-1234-2009; Muller, Alfred/A-3548-2009; Savin, Daniel/B-9576-2012; Schippers, Stefan/A-7786-2008 OI Muller, Alfred/0000-0002-0030-6929; Savin, Daniel/0000-0002-1111-6610; Schippers, Stefan/0000-0002-6166-7138 NR 33 TC 31 Z9 31 U1 1 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD AUG PY 2003 VL 147 IS 2 BP 421 EP 435 DI 10.1086/375688 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 704BY UT WOS:000184318900010 ER PT J AU Marshall, JD Riley, WJ McKone, TE Nazaroff, WW AF Marshall, JD Riley, WJ McKone, TE Nazaroff, WW TI Intake fraction of primary pollutants: motor vehicle emissions in the South Coast Air Basin SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE exposure assessment; microenvironment; carbon monoxide; benzene ID VOLATILE ORGANIC-COMPOUNDS; CALIFORNIA REFORMULATED GASOLINE; CARBON-MONOXIDE; IN-VEHICLE; LOS-ANGELES; PASSENGER COMPARTMENT; EXPOSURE EFFICIENCY; PERSONAL EXPOSURE; BENZENE EXPOSURE; MEXICO-CITY AB The intake fraction is defined for a specific species and emission source as the ratio of attributable population intake to total emissions. Focusing on California's South Coast Air Basin (SoCAB) as a case study, we combine ambient monitoring data with time-activity patterns to estimate the population intake of carbon monoxide and benzene emitted from motor vehicles during 1996-1999. In addition to exposures to ambient concentrations, three microenvironments are considered in which the exposure concentration of motor vehicle emissions is higher than in ambient air: in and near vehicles, inside a building that is near a freeway, and inside a residence with an attached garage. Incorporating data on motor vehicle emissions estimated by the EMFAC2000 model, we estimate that the 15 million people in the SoCAB inhale 0.003-0.009% (34 85 per million, with a best estimate of 47 per million) of primary, nonreactive compounds emitted into the basin by motor vehicles. This population intake of primary motor vehicle emissions is approximately 50% higher than the average ambient concentration times the average breathing rate, owing to higher concentrations in the three microenviromments and also to the temporal and spatial correlation among breathing rates, concentrations, and population densities. The approach demonstrated here can inform policy decisions requiring a metric of population exposure to airborne pollutants. (C) 2003 Elsevier Ltd. All rights reserved. C1 Lawrence Berkeley Natl Lab, Indoor Environm Dept, Berkeley, CA 94720 USA. Univ Calif Berkeley, Energy & Resources Grp, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. RP Nazaroff, WW (reprint author), Lawrence Berkeley Natl Lab, Indoor Environm Dept, Berkeley, CA 94720 USA. RI Nazaroff, William/C-4106-2008; Marshall, Julian/B-2998-2012; Riley, William/D-3345-2015 OI Nazaroff, William/0000-0001-5645-3357; Riley, William/0000-0002-4615-2304 NR 67 TC 60 Z9 64 U1 1 U2 9 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 AUG PY 2003 VL 37 IS 24 BP 3455 EP 3468 DI 10.1016/S1352-2310(03)00269-3 PG 14 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 702RM UT WOS:000184237200013 ER PT J AU Villasenor, R Magdaleno, M Quintanar, A Gallardo, JC Lopez, MT Jurado, R Miranda, A Aguilar, M Melgarejo, LA Palmerin, E Vallejo, CJ Barchet, WR AF Villasenor, R Magdaleno, M Quintanar, A Gallardo, JC Lopez, MT Jurado, R Miranda, A Aguilar, M Melgarejo, LA Palmerin, E Vallejo, CJ Barchet, WR TI An air quality emission inventory of offshore operations for the exploration and production of petroleum by the Mexican oil industry SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE emission inventory; emission factors; marine platforms; Gulf of Mexico; air quality modeling AB An air quality screening study was performed to assess the impacts of emissions from the offshore operations of the oil and gas exploration and production by Mexican industry in the Campeche Sound, which includes the states of Tabasco and Campeche in southeast Mexico. The major goal of this study was the compilation of an emission inventory (EI) for elevated, boom and ground level flares, processes, internal combustion engines and fugitive emissions. This inventory is so far the most comprehensive emission register that has ever been developed for the Mexican petroleum industry in this area. The El considered 174 offshore platforms, the compression station at Atasta, and the Maritime Ports at Dos Bocas and Cayo Areas. The offshore facilities identified as potential emitters in the area were the following: (1) trans-shipment stations, (2) a maritime floating port terminal, (3) drilling platforms, (4) crude oil recovering platforms, (5) crude oil production platforms, (6) linking platforms, (7) water injection platforms, (8) pumping platforms, (9) shelter platforms, (10) telecommunication platforms, (11) crude oil measurement platforms, and (12) flaring platforms. Crude oil storage tanks, helicopters and marine ship tankers were also considered to have an El accurate enough for air quality regulations and mesoscale modeling of atmospheric pollutants. Historical ambient data measure at two onshore petroleum facilities were analyzed to measure air quality impacts on nearby inhabited coastal areas, and a source-receptor relationship for flares at the Ixtoc marine complex was performed to investigate health-based standards for offshore workers. A preliminary air quality model simulation was performed to observe the transport and dispersion patterns Of SO2, which is the main pollutant emitted from the offshore platforms. The meteorological wind and temperature fields were generated with CALMET, a diagnostic meteorological model that used surface observations and upper air soundings from a 4-day field campaign conducted in February of 1999. The CALMET meteorological output and the generated El drove the transport and dispersion model, CALPUFF. Model results were compared with SO2 measurements taken from the monitoring network at Dos Bocas. (C) 2003 Elsevier Ltd. All rights reserved. C1 Inst Mexicano Petr, Mexico City 07730, DF, Mexico. Battelle Mem Inst, Pacific NW Div, Richland, WA USA. RP Villasenor, R (reprint author), Av Platanales 252-5 Col Nueva Santa Maria, Mexico City 02800, DF, Mexico. EM rvillase@imp.mx NR 15 TC 17 Z9 21 U1 3 U2 17 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 AUG PY 2003 VL 37 IS 26 BP 3713 EP 3729 DI 10.1016/S1352-2310(03)00445-X PG 17 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 704RH UT WOS:000184353300011 ER PT J AU Bailey, VL Smith, JL Bolton, H AF Bailey, VL Smith, JL Bolton, H TI Novel antibiotics as inhibitors for the selective respiratory inhibition method of measuring fungal : bacterial ratios in soil SO BIOLOGY AND FERTILITY OF SOILS LA English DT Article DE novel antibiotics; respiratory inhibition method; fungal : bacterial ratio; bactericide; fungicide ID SUBSTRATE-INDUCED RESPIRATION; MICROBIAL BIOMASS; FOREST SOILS; FUNGICIDES; GRASSLAND; NITROGEN; DECOMPOSITION; ERGOSTEROL; MANAGEMENT; COMMUNITY AB The use of the selective inhibition (Sl) method for measuring fungal:bacterial ratios may be limited due to biocide selectivity and the overlap of antibiotic activity. This study evaluated novel pairs of antibiotics for their specificity in soils of different origins and their potential reduction in inhibition of non-target organisms. Four soils selected for this study were from a semi-arid shrub-steppe, a loblolly pine forest and two grassland sites (restored and farmed prairie plots). Three bactericides were tested: oxytetracycline hydrochloride, streptomycin sulphate, and bronopol. Three fungicides were tested: captan, ketoconazole, and nystatin. The inhibitor additivity ratio and fungal:bacterial ratios were calculated from control and treated soils where inhibition was measured as CO2 respiration reduction with biocides. We were able to minimize non-target inhibition by the antibiotics to <5% and thus calculate reliable fungal: bacterial ratios using captan to inhibit fungi in all four soils, and bronopol to inhibit bacteria in three of the four soils. The most successful bactericide in the restored prairie was oxytetracycline-HCl. Our results demonstrate that application of novel antibiotics is not uniformly successful in soils of different origin and that the Sl technique requires more than just optimization of antibiotic concentration; it also requires optimization of antibiotic selection. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. ARS, USDA, Pullman, WA USA. RP Bailey, VL (reprint author), Pacific NW Natl Lab, MSIN P7-50,902 Battelle Blvd, Richland, WA 99352 USA. EM vanessa.bailey@pnl.gov RI Bolton, Harvey/E-5583-2011; OI Bailey, Vanessa/0000-0002-2248-8890 NR 27 TC 36 Z9 41 U1 1 U2 28 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0178-2762 J9 BIOL FERT SOILS JI Biol. Fertil. Soils PD AUG PY 2003 VL 38 IS 3 BP 154 EP 160 DI 10.1007/s00374-003-0620-7 PG 7 WC Soil Science SC Agriculture GA 767FL UT WOS:000188429500004 ER PT J AU Tran, NL Colvin, ME Gronert, S Wu, WM AF Tran, NL Colvin, ME Gronert, S Wu, WM TI Catalysis of decarboxylation by an adjacent negative charge: A theoretical approach SO BIOORGANIC CHEMISTRY LA English DT Article ID OROTIDINE 5'-MONOPHOSPHATE DECARBOXYLASE; PHYSICAL ORGANIC-CHEMISTRY; PROFICIENT ENZYME; MONOPHOSPHATE DECARBOXYLASE; RATE ACCELERATION; MECHANISM; DESTABILIZATION; BENZISOXAZOLES; STABILIZATION AB We have calculated the rate acceleration in decarboxylation reactions that can be accomplished by charge-charge repulsion between the substrate carboxylate and an adjacent negative charge in media of various dielectric constants. It has been shown that a full negative charge or surrounding partial negative charges will have the same effect. It is concluded that the rate of decarboxylation could be greatly accelerated by the presence of a negative charge nearby. For example, in media with dielectric constants from 5.62 to 20.7, a 10(8)-fold rate acceleration could be achieved by a negative charge placed 3.77 Angstrom away from the substrate carboxylate group. However, pK(a) perturbation on two carboxylate groups at close proximity may limit the extent of catalysis. It should also be noted that the extent of catalysis does not change much when the dielectric constant varies from 5.62 to 20.7. (C) 2003 Elsevier Science (USA). All rights reserved. C1 San Francisco State Univ, Dept Chem & Biochem, San Francisco, CA 94132 USA. Lawrence Livermore Natl Lab, Phys Biosci Inst, Div Computat & Syst Biol, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Wu, WM (reprint author), San Francisco State Univ, Dept Chem & Biochem, 1600 Holloway Ave, San Francisco, CA 94132 USA. RI Gronert, Scott/C-2304-2016 OI Gronert, Scott/0000-0002-0408-9765 FU NIGMS NIH HHS [S06 GM52588] NR 19 TC 8 Z9 8 U1 0 U2 7 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0045-2068 J9 BIOORG CHEM JI Bioorganic Chem. PD AUG PY 2003 VL 31 IS 4 BP 271 EP 277 DI 10.1016/S0045-2068(03)00028-2 PG 7 WC Biochemistry & Molecular Biology; Chemistry, Organic SC Biochemistry & Molecular Biology; Chemistry GA 707JM UT WOS:000184507600001 PM 12877877 ER PT J AU Kulkarni, RV Slepoy, A Singh, RRP Cox, DL Pazmandi, F AF Kulkarni, RV Slepoy, A Singh, RRP Cox, DL Pazmandi, F TI Theoretical modeling of prion disease incubation SO BIOPHYSICAL JOURNAL LA English DT Article ID SCRAPIE AGENT; TRANSMISSION DYNAMICS; HAMSTER SCRAPIE; PROTEIN; BSE; PATHOGENESIS; MICE; EPIDEMIOLOGY; REPLICATION; PARAMETERS AB We apply a theoretical aggregation model to laboratory and epidemiological prion disease incubation time data. In our model, slow growth of misfolded protein aggregates from small initial seeds controls the latent or lag phase; aggregate fissioning and subsequent spreading leads to an exponential growth phase. Our model accounts for the striking reproducibility of incubation times for high dose inoculation of lab animals. In particular, low dose yields broad incubation time distributions, and increasing dose narrows distributions and yields sharply defined onset times. We also explore how incubation time statistics depend upon aggregate morphology. We apply our model to fit the experimental dose-incubation curves for distinct strains of scrapie, and explain logarithmic variation at high dose and deviations from logarithmic behavior at low dose. We use this to make testable predictions for infectivity time-course experiments. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP NEC Labs Amer, 4 Independence Way, Princeton, NJ 08540 USA. EM kulkarni@physics.ucdavis.edu NR 37 TC 11 Z9 12 U1 0 U2 1 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 EI 1542-0086 J9 BIOPHYS J JI Biophys. J. PD AUG PY 2003 VL 85 IS 2 BP 707 EP 718 DI 10.1016/S0006-3495(03)74514-7 PG 12 WC Biophysics SC Biophysics GA 705ZZ UT WOS:000184428300004 PM 12885622 ER PT J AU Resat, H Ewald, JA Dixon, DA Wiley, HS AF Resat, H Ewald, JA Dixon, DA Wiley, HS TI An integrated model of epidermal growth factor receptor trafficking and signal transduction SO BIOPHYSICAL JOURNAL LA English DT Article ID INTRACELLULAR TRAFFICKING; POSTENDOCYTIC TRAFFICKING; MITOGENIC POTENCIES; KINASE ACTIVATION; TYROSINE KINASES; KINETIC-ANALYSIS; EGF RECEPTORS; ENDOCYTOSIS; INTERNALIZATION; PROTEIN AB Endocytic trafficking of many types of receptors can have profound effects on subsequent signaling events. Quantitative models of these processes, however, have usually considered trafficking and signaling independently. Here, we present an integrated model of both the trafficking and signaling pathway of the epidermal growth factor receptor (EGFR) using a probability weighted-dynamic Monte Carlo simulation. Our model consists of hundreds of distinct endocytic compartments and; 13,000 reactions/events that occur over a broad spatio-temporal range. By using a realistic multicompartment model, we can investigate the distribution of the receptors among cellular compartments as well as their potential signal transduction characteristics. Our new model also allows the incorporation of physiochemical aspects of ligand-receptor interactions, such as pH-dependent binding in different endosomal compartments. To determine the utility of this approach, we simulated the differential activation of the EGFR by two of its ligands, epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha). Our simulations predict that when EGFR is activated with TGF-alpha, receptor activation is biased toward the cell surface whereas EGF produces a signaling bias toward the endosomal compartment. Experiments confirm these predictions from our model and simulations. Our model accurately predicts the kinetics and extent of receptor downregulation induced by either EGF or TGF-alpha. Our results suggest that receptor trafficking controls the compartmental bias of signal transduction, rather than simply modulating signal magnitude. Our model provides a new approach to evaluating the complex effect of receptor trafficking on signal transduction. Importantly, the stochastic and compartmental nature of the simulation allows these models to be directly tested by high-throughput approaches, such as quantitative image analysis. C1 Pacific NW Natl Lab, Div Biol Sci, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Resat, H (reprint author), Pacific NW Natl Lab, Div Biol Sci, POB 999,Mail Stop K1-92, Richland, WA 99352 USA. RI Ewald, Jonathan/D-6698-2012; OI Wiley, Steven/0000-0003-0232-6867 NR 49 TC 109 Z9 111 U1 0 U2 8 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD AUG PY 2003 VL 85 IS 2 BP 730 EP 743 DI 10.1016/S0006-3495(03)74516-0 PG 14 WC Biophysics SC Biophysics GA 705ZZ UT WOS:000184428300006 PM 12885624 ER PT J AU Sorin, EJ Rhee, YM Nakatani, BJ Pande, VS AF Sorin, EJ Rhee, YM Nakatani, BJ Pande, VS TI Insights into nucleic acid conformational dynamics from massively parallel stochastic simulations SO BIOPHYSICAL JOURNAL LA English DT Article ID EXCHANGE MOLECULAR-DYNAMICS; STATISTICAL-MECHANICAL MODEL; POISSON-BOLTZMANN EQUATION; DNA HAIRPIN-LOOP; BETA-HAIRPIN; SECONDARY STRUCTURE; RNA HAIRPIN; NATIVE TOPOLOGY; FOLDING SIMULATIONS; CONTINUUM SOLVENT AB The helical hairpin is one of the most ubiquitous and elementary secondary structural motifs in nucleic acids, capable of serving functional roles and participating in long-range tertiary contacts. Yet the self-assembly of these structures has not been well-characterized at the atomic level. With this in mind, the dynamics of nucleic acid hairpin formation and disruption have been studied using a novel computational tool: large-scale, parallel, atomistic molecular dynamics simulation employing an inhomogeneous distributed computer consisting of more than 40,000 processors. Using multiple methodologies, over 500 mus of atomistic simulation time has been collected for a large ensemble of hairpins (sequence 5'-GGGC[GCAA]GCCU-3'), allowing characterization of rare events not previously observable in simulation. From uncoupled ensemble dynamics simulations in unperturbed folding conditions, we report on 1), competing pathways between the folded and unfolded regions of the conformational space; 2), observed nonnative stacking and basepairing traps; and 3), a helix unwinding-rewinding mode that is differentiated from the unfolding and folding dynamics. A heterogeneous transition state ensemble is characterized structurally through calculations of conformer-specific folding probabilities and a multiplexed replica exchange stochastic dynamics algorithm is used to derive an approximate folding landscape. A comparison between the observed folding mechanism and that of a peptide beta-hairpin analog suggests that although native topology defines the character of the folding landscape, the statistical weighting of potential folding pathways is determined by the chemical nature of the polymer. C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Stanford Univ, Dept Biophys, Stanford, CA 94305 USA. Stanford Univ, Dept Biol Struct, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. RP Pande, VS (reprint author), Stanford Univ, Dept Chem, Stanford, CA 94305 USA. RI Rhee, Young/E-9940-2012 FU NIGMS NIH HHS [1P20 GM64782-01] NR 76 TC 71 Z9 72 U1 3 U2 32 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD AUG PY 2003 VL 85 IS 2 BP 790 EP 803 DI 10.1016/S0006-3495(03)74520-2 PG 14 WC Biophysics SC Biophysics GA 705ZZ UT WOS:000184428300010 PM 12885628 ER PT J AU Korneev, VA Nadeau, RM McEvilly, TV AF Korneev, VA Nadeau, RM McEvilly, TV TI Seismological studies at Parkfield IX: Fault-zone imaging using guided wave attenuation SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID SAN-ANDREAS FAULT; CALIFORNIA; LANDERS; MICROEARTHQUAKES; PROPAGATION; RECURRENCE; PARAMETERS; DEPTH; RATES AB Numerical modeling studies and a growing number of observations have argued for the propagation of fault-zone guided waves (FZGWs) within a San Andreas Fault (SAF) zone that is 100-200 in wide at seismogenic depths and with 20%-40% lower shear-wave velocity than the adjacent unfaulted rock. Thousands of microearthquakes have been recorded since 1987 by the borehole High-Resolution Seismic Network at Parkfield, California, and they provide a comprehensive data set for characterizing wave propagation in the SAF zone. Using microearthquakes we confirm that FZGWs at Parkfield are generated within the fault zone (FZ) and that they are most prominent late in the coda of S. Numerical waveform, modeling and guided-wave amplitude tomographic inversion show clearly that FZGWs are significantly less attenuated in a well-defined region of the FZ. This region plunges to the northwest along the northwest boundary of the region of highest moment release and separates locked and slipping sections of the SAF at depth, as determined independently from geodesy, seismicity, and the recurrence rates of characteristically repeating microearthquakes. We interpret this localized zone of strong FZGW propagation to be the northwest edge of the M 6 asperity at Parkfield. The mechanism for low FZGW attenuation in the zone is possibly due to dewatering by fracture closure and/or fault-normal compression or changes in fracture orientation due to a complex stress or strain field at the boundary between creeping and locked zones of the SAF. C1 Lawrence Berkeley Natl Lab, Div Earth Sci, Ctr Computat Seismol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley Seismol Lab, Berkeley, CA 94720 USA. RP Korneev, VA (reprint author), Lawrence Berkeley Natl Lab, Div Earth Sci, Ctr Computat Seismol, Berkeley, CA 94720 USA. NR 23 TC 30 Z9 30 U1 0 U2 0 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 USA SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD AUG PY 2003 VL 93 IS 4 BP 1415 EP 1426 DI 10.1785/0120020114 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 721NP UT WOS:000185322700001 ER PT J AU Lewandowski, JLV AF Lewandowski, JLV TI Numerical loading of a Maxwellian probability distribution function SO CANADIAN JOURNAL OF PHYSICS LA English DT Article ID SCHEME AB A renormalization procedure for the numerical loading of a Maxwellian probability distribution function (PDF) is formulated. The procedure, which involves the solution of three coupled nonlinear equations, yields a numerically loaded PDF with improved properties for higher velocity moments. This method is particularly useful for low-noise particle-in-cell simulations with electron dynamics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Lewandowski, JLV (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 2 Z9 2 U1 0 U2 0 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0008-4204 J9 CAN J PHYS JI Can. J. Phys. PD AUG PY 2003 VL 81 IS 8 BP 989 EP 996 DI 10.1139/P03-080 PG 8 WC Physics, Multidisciplinary SC Physics GA 731TE UT WOS:000185901900002 ER PT J AU Talon, C Cuello, GJ Gonzalez, MA Bermejo, FJ Cabrillo, C Connatser, R AF Talon, C Cuello, GJ Gonzalez, MA Bermejo, FJ Cabrillo, C Connatser, R TI A comparative study of the low-frequency dynamics of the two isomers of propanol SO CHEMICAL PHYSICS LA English DT Article; Proceedings Paper CT Conference on Quasielastic Neutron Scattering (QENS) CY SEP, 2002 CL POTSDAM, GERMANY ID GLASSES; HEAT AB The low-temperature specific heat of the two isomers of propanol reveals significant differences between the temperature coefficients of both samples. The low- and intermediate-frequency regions of the generalised spectrum (densities of states) have been measured for both samples in glass and crystal states by means of neutron scattering. Assignment of the most prominent spectral features is facilitated by comparison with results from computer molecular dynamics simulations carried out using transferable potentials that include all the relevant molecular degrees of freedom. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. Univ Autonoma Madrid, Dept Fis Mat Condensada, E-28049 Madrid, Spain. Univ Basque Country, Dept Elect & Elect, E-48080 Leioa, Spain. CSIC, E-28006 Madrid, Spain. Argonne Natl Lab, Argonne, IL 60439 USA. RP Cuello, GJ (reprint author), Inst Max Von Laue Paul Langevin, BP 156, F-38042 Grenoble, France. RI Cuello, Gabriel/C-5831-2009; Gonzalez, Miguel/R-8330-2016 OI Cuello, Gabriel/0000-0003-3844-0602; Gonzalez, Miguel/0000-0002-3478-0215 NR 12 TC 5 Z9 5 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD AUG 1 PY 2003 VL 292 IS 2-3 BP 263 EP 271 DI 10.1016/S0301-0104(03)00053-3 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 707LB UT WOS:000184511200016 ER PT J AU Maira-Vidal, A Gonzalez, MA Cabrillo, C Bermejo, FJ Jimenez-Ruiz, M Saboungi, ML Otomo, T Fayon, F Enciso, E Price, DL AF Maira-Vidal, A Gonzalez, MA Cabrillo, C Bermejo, FJ Jimenez-Ruiz, M Saboungi, ML Otomo, T Fayon, F Enciso, E Price, DL TI Neutron scattering on a re-entrant binary liquid mixture SO CHEMICAL PHYSICS LA English DT Article; Proceedings Paper CT Conference on Quasielastic Neutron Scattering (QENS) CY SEP, 2002 CL POTSDAM, GERMANY DE re-entrant mixture; neutron scattering; SANS; QENS ID CRITICAL-POINT; HEAVY-WATER; BEHAVIOR; 3-METHYLPYRIDINE AB Small-angle and quasielastic neutron scattering measurements have been carried out on mixtures of 3-methylpyridine/heavy water (3MP/HW). Depending upon the relative concentration these mixtures are fully miscible or show a closed-loop phase diagram. Two mixtures corresponding to the fully miscible composition as well as a phase-separating sample are studied together with neat 3MP liquid. The SANS results show relatively large coherence lengths even for the miscible binary liquid. Quasielastic neutron scattering reveals a significant slowing down of the 3MP dynamics within the mixture as compared to that of pure 3MP. As the phase-separation line is approached from below the translational diffusion coefficients show a clear signature of critical slowing down that mimics the behavior of the shear viscosity. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. CSIC, E-28006 Madrid, Spain. Univ Basque Country, Dept Elect & Elect, Bilbao 48080, Spain. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Orleans, CNRS, F-45071 Orleans 2, France. KEK, Neutron Sci Lab, Tsukuba, Ibaraki 3050801, Japan. Univ Complutense Madrid, Dept Quim Fis 1, Madrid 28040, Spain. RP Gonzalez, MA (reprint author), Inst Max Von Laue Paul Langevin, BP 156,6 Rue Jules Horowitz, F-38042 Grenoble 9, France. RI Fayon, Franck/C-1835-2008; Price, David Long/A-8468-2013; Saboungi, Marie-Louise/C-5920-2013; Otomo, Toshiya/C-6178-2013; Gonzalez, Miguel/R-8330-2016 OI Saboungi, Marie-Louise/0000-0002-0607-4815; Otomo, Toshiya/0000-0002-7210-8374; Gonzalez, Miguel/0000-0002-3478-0215 NR 24 TC 4 Z9 4 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD AUG 1 PY 2003 VL 292 IS 2-3 BP 273 EP 281 DI 10.1016/S0301-0104(03)00081-8 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 707LB UT WOS:000184511200017 ER PT J AU Russina, M Russina, O Mezei, F AF Russina, M Russina, O Mezei, F TI Heterogeneous large amplitude atomic motion in supercooled liquids SO CHEMICAL PHYSICS LA English DT Article; Proceedings Paper CT Conference on Quasielastic Neutron Scattering (QENS) CY SEP, 2002 CL POTSDAM, GERMANY ID GLASS-TRANSITION; ZINC-CHLORIDE; SCATTERING; RELAXATION; DYNAMICS; INTENSITY; BRILLOUIN; ZNCL2 AB One of the central questions in glass physics is the dynamic nature of the glass transition. Essential issues are the type of atomic motions involved and their homogeneity or heterogeneity. Previous experimental studies of the dynamic heterogeneity performed by special NMR techniques for times >10(-6) s and by incoherent neutron scattering were restricted to the alpha-relaxation process. Here we review the results of neutron scattering studies focused on the picosecond time domain showing that fast beta-process corresponds to large amplitude cluster like heterogeneous motion. (C) 2003 Published by Elsevier Science B.V. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Hahn Meitner Inst Berlin GmbH, D-14109 Berlin, Germany. RP Los Alamos Natl Lab, POB 1663,MS H805, Los Alamos, NM 87545 USA. EM russina@lanl.gov RI Russina, Olga/G-9780-2012; Russina, Margarita/E-9886-2016 OI Russina, Margarita/0000-0003-2067-606X NR 26 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 EI 1873-4421 J9 CHEM PHYS JI Chem. Phys. PD AUG 1 PY 2003 VL 292 IS 2-3 BP 325 EP 331 DI 10.1016/S0301-0104(03)00256-8 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 707LB UT WOS:000184511200022 ER PT J AU Marchetti, AA Knize, MG Chiarappa-Zucca, ML Pletcher, RJ Layton, DW AF Marchetti, AA Knize, MG Chiarappa-Zucca, ML Pletcher, RJ Layton, DW TI Biodegradation of potential diesel oxygenate additives: dibutyl maleate (DBM), and tripropylene glycol methyl ether (TGME) SO CHEMOSPHERE LA English DT Article DE fuel; biotransformation; aerobic; recalcitrant; MTBE; benzene AB The addition of oxygen-bearing compounds to diesel fuel considerably reduces particulate emissions. TGME and DBM have been identified as possible diesel additives based on their physicochemical characteristics and performance in engine tests. Although these compounds will reduce particulate emissions, their potential environmental impacts are unknown. As a means of characterizing their persistence in environmental media such as soil and groundwater, we conducted a series of biodegradation tests of DBM and TGME. Benzene and methyl tertiary butyl ether (MTBE) were also tested as reference compounds. Primary degradation of DBM fully occurred within 3 days, while TGME presented a lag phase of approximately 8 days and was not completely degraded by day 28. Benzene primary degradation occurred completely by day 3 and MTBE did not degrade at all. The total mineralized fractions of DBM and TGME achieved constant values as a function of time of similar to65% and similar to40%, respectively. Transport predictions show that, released to the environment, DBM and TGME would concentrate mostly in soils and waters with minimal impact to air. From an environmental standpoint, these results combined with the transport predictions indicate that DBM is a better choice than TGME as a diesel additive. Published by Elsevier Science Ltd. C1 Lawrence Livermore Natl Lab, Div Environm Sci, Livermore, CA 94550 USA. RP Marchetti, AA (reprint author), Lawrence Livermore Natl Lab, Div Environm Sci, 7000 E Ave,L-396, Livermore, CA 94550 USA. NR 15 TC 18 Z9 18 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-6535 J9 CHEMOSPHERE JI Chemosphere PD AUG PY 2003 VL 52 IS 5 BP 861 EP 868 DI 10.1016/S0045-6535(03)00293-5 PG 8 WC Environmental Sciences SC Environmental Sciences & Ecology GA 693UT UT WOS:000183737300009 PM 12757787 ER PT J AU Bickmore, BR Rosso, KM Nagy, KL Cygan, RT Tadanier, CJ AF Bickmore, BR Rosso, KM Nagy, KL Cygan, RT Tadanier, CJ TI Ab initio determination of edge surface structures for dioctahedral 2 : 1 phyllosilicates: Implications for acid-base reactivity SO CLAYS AND CLAY MINERALS LA English DT Article DE ab initio; clay edge surfaces; density functional theory; dissolution kinetics; MUSIC; pyrophyllite; surface structure ID TOTAL-ENERGY CALCULATIONS; ATOMIC-FORCE MICROSCOPY; ELECTRICAL DOUBLE-LAYER; CLAY MINERAL PARTICLE; DISSOLUTION KINETICS; MOLECULAR-DYNAMICS; AQUEOUS-SOLUTIONS; IN-SITU; KAOLINITE; CRYSTALS AB The atomic structure of dioctahedral 2:1 phyllosilicate edge surfaces was calculated using pseudopotential planewave density functional theory. Bulk structures of pyrophyllite and ferripyrophyllite were optimized using periodic boundary conditions, after which crystal chemical methods were used to obtain initial terminations for ideal (110)- and (010)-type edge surfaces. The edge surfaces were protonated using various schemes to neutralize the surface charge, and total minimized energies were compared to identify which schemes are the most energetically favorable. The calculations show that significant surface relaxation should occur on the (110)-type faces, as well as in response to different protonation schemes on both surface types. This result is consistent with atomic force microscopy observations of phyllosilicate dissolution behavior. Bond-valence methods incorporating bond lengths from calculated structures can be used to predict intrinsic acidity constants for surface functional groups on (110)- and (010)-type edge surfaces. However, the occurrence of surface relaxation poses problems for applying current bond-valence methods. An alternative method is proposed that considers bond relaxation, and accounts for the energetics of various protonation schemes on phyllosilicate edges. C1 Brigham Young Univ, Dept Geol, Provo, UT 84602 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Illinois, Dept Earth & Environm Sci, Chicago, IL 60607 USA. Sandia Natl Labs, Dept Geochem, Albuquerque, NM 87185 USA. Virginia Tech, Dept Geol Sci, Blacksburg, VA 24061 USA. Virginia Tech, Charles E Via Dept Civil & Environm Engn, Blacksburg, VA 24061 USA. RP Bickmore, BR (reprint author), Brigham Young Univ, Dept Geol, Provo, UT 84602 USA. NR 49 TC 92 Z9 93 U1 4 U2 35 PU CLAY MINERALS SOCIETY PI AURORA PA PO BOX 460130, AURORA, CO 80046-0130 USA SN 0009-8604 J9 CLAY CLAY MINER JI Clay Clay Min. PD AUG PY 2003 VL 51 IS 4 BP 359 EP 371 DI 10.1346/CCMN.2003.0510401 PG 13 WC Chemistry, Physical; Geosciences, Multidisciplinary; Mineralogy; Soil Science SC Chemistry; Geology; Mineralogy; Agriculture GA 711PK UT WOS:000184750100001 ER PT J AU Herzog, H Caldeira, K Reilly, J AF Herzog, H Caldeira, K Reilly, J TI An issue of permanence: Assessing the effectiveness of temporary carbon storage SO CLIMATIC CHANGE LA English DT Article ID GREENHOUSE-GAS EMISSIONS; THERMODYNAMICS; DISSOCIATION; RADIOCARBON; SEAWATER; OCEAN; ACID AB In this paper, we present a method to quantify the effectiveness of carbon mitigation options taking into account the 'permanence' of the emissions reduction. While the issue of permanence is most commonly associated with a 'leaky' carbon sequestration reservoir, we argue that this is an issue that applies to just about all carbon mitigation options. The appropriate formulation of this problem is to ask 'what is the value of temporary storage?' Valuing temporary storage can be represented as a familiar economic problem, with explicitly stated assumptions about carbon prices and the discount rate. To illustrate the methodology, we calculate the sequestration effectiveness for injecting CO2 at various depths in the ocean. Analysis is performed for three limiting carbon price assumptions: constant carbon prices ( assumes constant marginal damages), carbon prices rise at the discount rate ( assumes efficient allocation of a cumulative emissions cap without a backstop technology), and carbon prices first rise at the discount rate but become constant after a given time ( assumes introduction of a backstop technology). Our results show that the value of relatively deep ocean carbon sequestration can be nearly equivalent to permanent sequestration if marginal damages ( i.e., carbon prices) remain constant or if there is a backstop technology that caps the abatement cost in the not too distant future. On the other hand, if climate damages are such as to require a fixed cumulative emissions limit and there is no backstop, then a storage option with even very slow leakage has limited value relative to a permanent storage option. C1 MIT, Lab Energy & Environm, Cambridge, MA 02139 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. MIT, Joint Program Sci & Policy Global Change, Cambridge, MA 02139 USA. RP Herzog, H (reprint author), MIT, Lab Energy & Environm, 77 Massachusetts Ave,Bldg E40-471, Cambridge, MA 02139 USA. RI Caldeira, Ken/E-7914-2011 NR 38 TC 75 Z9 76 U1 1 U2 9 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0165-0009 J9 CLIMATIC CHANGE JI Clim. Change PD AUG PY 2003 VL 59 IS 3 BP 293 EP 310 DI 10.1023/A:1024801618900 PG 18 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 704CH UT WOS:000184319800002 ER PT J AU Echekki, T Chen, JH AF Echekki, T Chen, JH TI Direct numerical simulation of autoignition in non-homogeneous hydrogen-air mixtures SO COMBUSTION AND FLAME LA English DT Article DE autoignition; hydrogen oxidation; DNS; turbulent combustion ID NONPREMIXED COUNTERFLOWING HYDROGEN; DIFFUSION FLAMES; ASYMPTOTIC ANALYSIS; IGNITION LIMITS; HEATED AIR; EXTINCTION; CHEMISTRY; STREAMS; OXYGEN AB The autoignition of spatially non-homogeneous hydrogen-air mixtures in 2-D random turbulence and mixture fraction fields is studied using the Direct Numerical Simulation (DNS) approach coupled with detailed kinetics. The coupling between chemistry and the unsteady scalar dissipation rate field is investigated over a wide range of different autoignition scenarios. The simulations show that autoignition is initiated at discrete spatially localized sites, referred to as kernels, by radical build-up in high-temperature, fuel-lean mixtures, and at relatively low dissipation rates. Detailed analysis of the dominant chemistry and the relative roles of reaction and diffusion is implemented by tracking the evolution of four representative kernels that characterize the range of ignition behaviors observed in the simulation. This evolution yields different autoignition delay scenarios as well as extinction at the different sites based on the local dissipation rates and their temporal histories. Where significant autoignition delay and extinction are observed, a shift in the relative roles of dominant reactions that contribute to radical production and consumption during this induction phase is observed. This shift is particularly characterized by an increased role of termination reactions during the intermediate stages of the induction period, which results in extinction in approximately two thirds of the ignition kernels in the computational domain. The fate of the different kernels is associated with: (1) the dissipation of heat that contributes to a slowdown in chemical reactions and a shift in the balance between chain-branching and chain-termination reactions; (2) the dissipation of mass that keeps the radical pool growth in check, and that is promoted by slower reaction rates; and (3) counter to the effects of dissipation of heat and intermediate species, the preferential diffusion of H-2 relative to both heat and its diluent, N-2, that promotes ignition. Ultimately, the balance between radical production and dissipation determines the success or failure of a given kernel to ignite. A new criterion for unsteady ignition is presented based on the instantaneous balance between radical production and dissipation. A Damkohler number, so defined, must remain above a critical value of unity at all times during the induction period if the kernel is to eventually ignite. Inherent in a multi-step kinetic description of ignition phenomena is the disparate time scales associated with different elementary reactions that, coupled with the characteristic scales of heat and mass dissipation, may yield different dominant chemistries at different stages of the induction process for a given kernel. To capture the strong history effects associated with radical build-up, new ignition progress variables based on key radical species are investigated. (C) 2003 The Combustion Institute. All rights reserved. C1 N Carolina State Univ, Dept Mech & Aerosp Engn, Raleigh, NC 27695 USA. Sandia Natl Labs, Combust Res Facil, MS 9051, Livermore, CA 94551 USA. RP Echekki, T (reprint author), N Carolina State Univ, Dept Mech & Aerosp Engn, Raleigh, NC 27695 USA. RI Echekki, Tarek/C-7394-2009; OI Echekki, Tarek/0000-0002-0146-7994 NR 25 TC 106 Z9 108 U1 0 U2 19 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 AUG PY 2003 VL 134 IS 3 BP 169 EP 191 DI 10.1016/S0010-2180(03)00088-9 PG 23 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 721ED UT WOS:000185303300002 ER PT J AU Ali, AN Son, SF Asay, BW Decroix, ME Brewster, MQ AF Ali, AN Son, SF Asay, BW Decroix, ME Brewster, MQ TI High-irradiance laser ignition of explosives SO COMBUSTION SCIENCE AND TECHNOLOGY LA English DT Article DE ignition; laser; explosives; HMX; TATB; DDT ID AMMONIUM PERCHLORATE PROPELLANTS; ENERGETIC MATERIALS; SURFACE EXOTHERM; DETONATION; ZONE; RDX AB A current issue important to high explosive safety is deflagration-to-detonation transitions (DDTs) in accident scenarios. In order to better understand the reactive mechanisms involved in DDT and to begin to approach the fast ignition and heating rates seen in DDT, high-irradiance (less than or equal to800W/cm 2 ) CO 2 laser ignition experiments were performed on the common high explosives octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Reported data include time to ignition as a function of laser irradiance, energy, and ignition temperature. A simple dual ignition criteria model (DICM) was used to interpret the HMX results. The DICM requires two basic criteria for ignition: (1) a minimum surface temperature must be reached and (2) a minimum energy concentration must exist within the solid. The DICM sucessfully predicted the slope transition trend and the critical ignition energy for HMX to within 10% of the measured values. TATB had a single dependence on irradiance over the entire range of heating rates. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Univ Illinois, Champaign, IL 61820 USA. RP Son, SF (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. OI Son, Steven/0000-0001-7498-2922 NR 37 TC 25 Z9 27 U1 4 U2 21 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0010-2202 J9 COMBUST SCI TECHNOL JI Combust. Sci. Technol. PD AUG PY 2003 VL 175 IS 8 BP 1551 EP 1571 DI 10.1080/00102200390219416 PG 21 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Energy & Fuels; Engineering GA 707BX UT WOS:000184490500006 ER PT J AU Qiao, ZJ AF Qiao, ZJ TI The Camassa-Holm hierarchy, N-dimensional integrable systems, and algebro-geometric solution on a symplectic submanifold SO COMMUNICATIONS IN MATHEMATICAL PHYSICS LA English DT Article ID R-MATRIX; EVOLUTION-EQUATIONS; PEAKED SOLITONS; SHALLOW-WATER; LATTICE; PEAKONS; PDES AB This paper shows that the Camassa-Holm (CH) spectral problem yields two different integrable hierarchies of nonlinear evolution equations (NLEEs), one is of negative order CH hierachy while the other one is of positive order CH hierarchy. The two CH hierarchies possess the zero curvature representations through solving a key matrix equation. We see that the well-known CH equation is included in the negative order CH hierarchy while the Dym type equation is included in the positive order CH hierarchy. Furthermore, under two constraint conditions between the potentials and the eigenfunctions, the CH spectral problem is cast in: 1. a new Neumann-like N-dimensional system when it is restricted into a symplectic submanifold of R-2N which is proven to be integrable by using the Dirac-Poisson bracket and the r-matrix process; and 2. a new Bargmann-like N-dimensional system when it is considered in the whole (2N) which is proven to be integrable by using the standard Poisson bracket and the r-matrix process. C1 Los Alamos Natl Lab, T 7, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, CNLS, Los Alamos, NM 87545 USA. Fudan Univ, Inst Math, Shanghai 200433, Peoples R China. RP Qiao, ZJ (reprint author), Los Alamos Natl Lab, T 7, MS B-284, Los Alamos, NM 87545 USA. NR 22 TC 110 Z9 116 U1 0 U2 1 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0010-3616 J9 COMMUN MATH PHYS JI Commun. Math. Phys. PD AUG PY 2003 VL 239 IS 1-2 BP 309 EP 341 DI 10.1007/s00220-003-0880-y PG 33 WC Physics, Mathematical SC Physics GA 707GY UT WOS:000184503900012 ER PT J AU Wakefield, LM Thordarson, G Nieto, AI Shyamala, G Galvez, JJ Anver, MR Cardiff, RD AF Wakefield, LM Thordarson, G Nieto, AI Shyamala, G Galvez, JJ Anver, MR Cardiff, RD TI Spontaneous pituitary abnormalities and mammary hyperplasia in FVB/NCr mice: Implications for mouse modeling SO COMPARATIVE MEDICINE LA English DT Article ID GLAND DEVELOPMENT; PLASMA-PROLACTIN; TRANSGENIC MICE; BREAST-CANCER; GROWTH; TUMORIGENESIS; RECEPTOR AB The FVB/N mouse strain is widely used in the generation of transgenic mouse models. We have observed that mammary glands of wild-type virgin female FVB/NCr mice frequently have the morphologic and histologic appearance of a gland during pregnancy. By 13 months of age, the mammary glands of more than 40% of the mice examined had lobuloalveolar hyperplasia that was characterized by the presence of secretory alveoli and distended ducts apparently containing secretory material. The prevalence of this phenotype further increased with age. The mammary phenotype was highly correlated with the presence of proliferative, prolactin-secreting lesions in the pituitary gland. In mice aged 18 to 23 months, hyperplasia of the pars distalis was seen in 11 of 21 mice (52%), and a further 4 of 21 mice (19%) had pituitary adenomas. Pituitary hyperplasia was already evident in some mice as young as nine months. The pituitary phenotype was also associated with high prevalence (4/6 mice) of spontaneous mammary tumors in aged multiparous, but not virgin FVB/NCr mice. This high prevalence of pituitary abnormalities and their effects on the mammary gland have important consequences for the interpretation of new phenotypes generated in transgenic models using this mouse substrain. C1 Univ Calif Davis, Dept Med Pathol, Davis, CA 95616 USA. Univ Calif Davis, Ctr Comparat Med, Davis, CA 95616 USA. NCI, Lab Cell Regulat & Carcinogenesis, Bethesda, MD 20892 USA. Univ Calif Santa Cruz, Sinsheimer Labs, Santa Cruz, CA 95064 USA. Univ Complutense Madrid, Fac Vet, Dept Patol Anim 2, E-28040 Madrid, Spain. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. NCI, Sci Applicat Int Corp, Pathol Histotechnol Lab, Frederick, MD 21702 USA. RP Cardiff, RD (reprint author), Univ Calif Davis, Dept Med Pathol, 98 Cty Rd & Hutchison Dr, Davis, CA 95616 USA. FU PHS HHS [N01-C0-12400] NR 24 TC 25 Z9 26 U1 0 U2 1 PU AMER ASSOC LABORATORY ANIMAL SCIENCE PI MEMPHIS PA 9190 CRESTWYN HILLS DR, MEMPHIS, TN 38125 USA SN 1532-0820 J9 COMPARATIVE MED JI Comparative Med. PD AUG PY 2003 VL 53 IS 4 BP 424 EP 432 PG 9 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 721FD UT WOS:000185305600012 PM 14524419 ER PT J AU Nieto, AI Shyamala, G Galvez, JJ Thordarson, G Wakefield, LM Cardiff, RD AF Nieto, AI Shyamala, G Galvez, JJ Thordarson, G Wakefield, LM Cardiff, RD TI Persistent mammary hyperplasia in FVB/N mice SO COMPARATIVE MEDICINE LA English DT Article ID GLAND INVOLUTION; CELL-DEATH; MOUSE AB The inbred FVB/N mouse strain is widely used for creating transgenic mice. Over the past decade, persistent mammary hyperplasia has been detected in many multiparous FVB/N female mice sent to the University of California, Davis (UCD) Mutant Mouse Pathology Laboratory (MMPL) by a number of different laboratories. However, the experimental details concerning most specimens were not always available. To confirm these empiric findings, experiments were carried out to evaluate the mammary glands of FVB/N mice under controlled conditions. Persistent mammary hyperplasia that related to parity was found. Weeks after their first to fourth pregnancy, 10 FVB/N female mice from the Lawrence Berkeley National Laboratory (LBNL) colony were studied and the mammary glands were evaluated. The percentage of fat pad filled was estimated, using image analysis. Serum samples and the pituitary gland from other FVB/N mice from the LBNL were assayed for prolactin concentration. Multiparous FVB/N females consistently had persistent mammary hyperplasia. Four of seven females in the LBNL colony had hyperplasia after three pregnancies. A few foci of squamous nodules and sporadic carcinomas also were observed. Thus, some FVB/N females may have persistent mammary hyperplasia after three pregnancies without detectable pituitary abnormalities. Mammary carcinomas also may develop sporadically. These background phenotypes must be considered when interpreting the effect of genetic manipulation in FVB/N mice. C1 Univ Calif Davis, Dept Med Pathol, Davis, CA 95616 USA. Univ Calif Davis, Ctr Comparat Med, Davis, CA 95616 USA. Univ Complutense Madrid, Fac Vet, Dept Patol Anim 2, E-28040 Madrid, Spain. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Santa Cruz, Sinsheimer Labs, Santa Cruz, CA 95064 USA. NCI, Lab Cell Regulat & Carcinogenesis, Bethesda, MD 20892 USA. RP Cardiff, RD (reprint author), Univ Calif Davis, Dept Med Pathol, 98 Cty Rd & Hutchison Dr, Davis, CA 95616 USA. FU NCI NIH HHS [CA 66541]; NCRR NIH HHS [U42-RR14905]; PHS HHS [N01-C0-12400] NR 12 TC 19 Z9 20 U1 0 U2 1 PU AMER ASSOC LABORATORY ANIMAL SCIENCE PI MEMPHIS PA 9190 CRESTWYN HILLS DR, MEMPHIS, TN 38125 USA SN 1532-0820 J9 COMPARATIVE MED JI Comparative Med. PD AUG PY 2003 VL 53 IS 4 BP 433 EP 438 PG 6 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 721FD UT WOS:000185305600013 PM 14524420 ER PT J AU Chang, SL Zhou, CQ AF Chang, SL Zhou, CQ TI Simulation of FCC riser flow with multiphase heat transfer and cracking reactions SO COMPUTATIONAL MECHANICS LA English DT Article DE multiphase flow; heat transfer; fluid catalytic cracking; CFD ID CATALYTIC-CRACKING; REACTORS; INJECTION; MODELS; MASS AB A validated Computational Fluid Dynamics (CFD) code ICRKFLO was developed for simulations of three-dimensional three-phase reacting flows in Fluid Catalytic Cracking (FCC) riser reactors. It calculates the product yields based on local flow properties by solving the fundamental conservation principles of mass, momentum, and energy for the flow properties associated with the gas, liquid, and solid phases. Unique phenomenological models and numerical techniques were developed specifically for the FCC flow simulation. The models include a spray vaporization model, a particle-solid interaction model, and an interfacial heat transfer model. The numerical techniques include a time-integral approach to overcome numerical stiffness problems in chemical kinetics rate calculations and a hybrid hydrodynamic-kinetic treatment to facilitate detailed kinetics calculations of cracking reactions. ICRKFLO has been validated with extensive test data from two pilot and one commercial FCC units. It is proven to be useful for advanced development of FCC riser reactors. C1 Purdue Univ Calumet, Dept Engn, Hammond, IN 46321 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Zhou, CQ (reprint author), Purdue Univ Calumet, Dept Engn, Hammond, IN 46321 USA. NR 23 TC 19 Z9 20 U1 4 U2 10 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0178-7675 J9 COMPUT MECH JI Comput. Mech. PD AUG PY 2003 VL 31 IS 6 BP 519 EP 532 DI 10.1007/s00466-003-0459-7 PG 14 WC Mathematics, Interdisciplinary Applications; Mechanics SC Mathematics; Mechanics GA 721FH UT WOS:000185306000008 ER PT J AU Rubinstein, R Zhou, Y AF Rubinstein, R Zhou, Y TI Schiestel's derivation of the Epsilon equation and two-equation modelling of rotating turbulence SO COMPUTERS & MATHEMATICS WITH APPLICATIONS LA English DT Article DE dissipation rate equation; rotating turbulence; two-equation turbulence models; multiple-scale turbulence models ID COMPUTATION; FLOWS AB As part of a more general program of developing multiple-scale models of turbulence, Schiestel suggested a derivation of the homogeneous part of the dissipation rate transport equation. Schiestel's approach is generalized to rotating turbulence. The resulting model reproduces the main features observed in decaying rotating turbulence. (C) 2003 Elsevier Ltd. All rights reserved. C1 NASA, Langley Res Ctr, ICASE, Hampton, VA 23681 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Rubinstein, R (reprint author), NASA, Langley Res Ctr, ICASE, Hampton, VA 23681 USA. NR 11 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0898-1221 J9 COMPUT MATH APPL JI Comput. Math. Appl. PD AUG PY 2003 VL 46 IS 4 BP 633 EP 638 DI 10.1016/S0898-1221(03)00247-5 PG 6 WC Computer Science, Interdisciplinary Applications; Mathematics, Applied SC Computer Science; Mathematics GA 724RB UT WOS:000185499600009 ER PT J AU King, JW Williams, LL AF King, JW Williams, LL TI Utilization of critical fluids in processing semiconductors and their related materials SO CURRENT OPINION IN SOLID STATE & MATERIALS SCIENCE LA English DT Review DE carbon dioxide; cleaning; critical fluid; drying; particulate removal; photoresist; semiconductors ID SUPERCRITICAL CARBON-DIOXIDE; TRANSPORT-CHEMICAL-DEPOSITION; PATTERN COLLAPSE; REACTIVE DEPOSITION; DIELECTRIC FILMS; PALLADIUM FILMS; CO2 FLUID; POLYMERS; REMOVAL; MICROELECTRONICS AB The use of carbon dioxide in its various states: supercritical (SC-CO2), liquid (L-CO2) or pellet form (snow-CO2) for processing and cleaning in semiconductor fabrication and related electronic devices is assessed in this review. An understanding of the fundamental mechanisms responsible for carbon dioxide-based processing, as in surface cleaning, is lacking. Although carbon dioxide is an excellent solvent for removing non-polar contaminants from a variety of surfaces, other CO2-based cleaning and surface modification processes are based on mechanical or morphological-induced changes in the interfacial region. The extremely low surface tension of CO2 is a favorable property in terms of its rapid and complete removal from the substrate after a treatment has been affected, and this characteristic of CO2 also accounts for its negligible effect on the morphology of the substrate, as utilized in the microelectronic industry. Applications of critical fluids in integrated circuit manufacturing operations, such as wafer cleaning, film deposition, photoresist stripping, drying, and particulate removal are noted. (C) 2004 Published by Elsevier Ltd. C1 Los Alamos Natl Lab, Supercrit Fluid Facil, C ACT Grp, Div Chem, Los Alamos, NM 87545 USA. RP King, JW (reprint author), Los Alamos Natl Lab, Supercrit Fluid Facil, C ACT Grp, Div Chem, Mail Stop E-537, Los Alamos, NM 87545 USA. EM kingjw@lanl.gov; williamsl@lanl.gov NR 66 TC 51 Z9 53 U1 1 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-0286 J9 CURR OPIN SOLID ST M JI Curr. Opin. Solid State Mat. Sci. PD AUG-OCT PY 2003 VL 7 IS 4-5 BP 413 EP 424 DI 10.1016/j.cossms.2004.02.002 PG 12 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 817YR UT WOS:000221213300019 ER PT J AU Alexander, RA Hanson, SW McClenahan, RL Worland, VP AF Alexander, RA Hanson, SW McClenahan, RL Worland, VP TI Using "fresh" to determine a source SO DESALINATION LA English DT Article; Proceedings Paper CT European Conference on Desalination and the Environment CY MAY 04-08, 2003 CL MALTA DE matrix; weighting factors; value factors; IWTF; BDAT AB Water scarcity is a problem facing the arid southwest portion of the United States. Compounding the scarcity issue is the fact that much of the water is also of poor quality. In recent years, the quest for sources of fresh water has intensified as the realization of the potential for long-term water shortages becomes a reality. This paper examines the definition of "fresh" water as a function of the end use of the water, i.e. human consumption, environmental release, or reuse for industrial or municipal applications. It is within this context that a discussion of the term "fresh" is evaluated as a defining criterion for potential sources. The technology to produce good quality water from poor quality sources exists. However, factors other than technology often control the decision making as to whether to treat a water source of poor quality, or continue to look for a source of higher quality. Some of these factors are: public acceptance, environmental impact, regulations, economics, human health risks, regional issues, political issues. The specific case discussed here uses a wastewater source that is highly controversial by its very nature, as it contains radionuclides and other industrial contaminants. The factors leading to this source being considered are as follows: (1) the municipal water production wells are 1500-2000 ft. (457.5-610 m) below the surface making production costly; (2) the groundwater quantity is limited and recharge is extremely slow; and, (3) the groundwater has a high level of naturally occurring silica (80-120 mg/l). The case facility, located in western portion of the United States, treats an average of 15,000 gpd (57 m(3)/d) through the use of chemical precipitation, sand filtration, ultrafiltration, ion exchange and reverse osmosis. The secondary waste (reject or concentrate) from this treatment process is further treated with electrodialysis-reversal and mechanical evaporation. The product from this facility is currently discharged, by regulatory permit, to the environment. The product water is being considered for reuse primarily for industrial applications. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Alexander, RA (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 2 TC 1 Z9 1 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0011-9164 J9 DESALINATION JI Desalination PD AUG 1 PY 2003 VL 156 IS 1-3 SI SI BP 209 EP 217 AR PII S0011-9164(03)00343-6 DI 10.1016/S0011-9164(03)00343-6 PG 9 WC Engineering, Chemical; Water Resources SC Engineering; Water Resources GA 696CE UT WOS:000183867400025 ER PT J AU Monteiro, OR Liu, HB AF Monteiro, OR Liu, HB TI Nucleation and growth of CVD diamond films on patterned substrates SO DIAMOND AND RELATED MATERIALS LA English DT Article DE diamond; nucleation; diamond-like carbon ID DEPOSITION; SILICON; FABRICATION; DEVICES/; FIELD AB The interest in using CVD diamond in the fabrication of microelectro-mechanical components has steadily increased over the C last few years. Typical technology for manufacturing such components involves the use of molds patterned in silicon or silicon dioxide. which are filled by diamond deposition. The degree of conformality of the CVD film and the characteristics of the diamond-substrate interface becomes critical for the successful fabrication and performance of such devices. We have investigated the growth of CVD diamond films on patterned substrates using a microwave plasma assisted deposition reactor. In particular, the use of seed layers to enhance nucleation on horizontal and vertical walls as well as to promote complete filling of narrow trenches is investigated. Scanning electron microscopy is used to characterize the nucleation and growth of the diamond films. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Gen Nanotechnol, Berkeley, CA 94708 USA. RP Monteiro, OR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 13 TC 13 Z9 13 U1 4 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD AUG PY 2003 VL 12 IS 8 BP 1357 EP 1361 DI 10.1016/S0925-9635(03)00106-7 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 704AG UT WOS:000184315100012 ER PT J AU Casadel, M Dietrich, WE Miller, NL AF Casadel, M Dietrich, WE Miller, NL TI Testing a model for predicting the timing and location of shallow landslide initiation in soil-mantled landscapes SO EARTH SURFACE PROCESSES AND LANDFORMS LA English DT Article DE shallow landslides; slope stability; hydrology; digital terrain modelling ID HYDROLOGIC RESPONSE; RAINFALL THRESHOLDS; EROSION THRESHOLDS; HAZARD EVALUATION; SLOPE STABILITY; EL-NINO; FLOW; STEEP; MORPHOLOGY; INTENSITY AB The growing availability of digital topographic data and the increased reliability of precipitation forecasts invite modelling efforts to predict the timing and location of shallow landslides in hilly and mountainous areas in order to reduce risk to an ever-expanding human population. Here, we exploit a rare data set to develop and test such a model. In a 1.7 km(2) catchment a near-annual aerial photographic coverage records just three single storm events over a 45 year period that produced multiple landslides. Such data enable us to test model performance by running the entire rainfall time series and determine whether just those three storms are correctly detected. To do this, we link a dynamic and spatially distributed shallow subsurface runoff model (similar to TOPMODEL) to an infinite slope model to predict the spatial distribution of shallow landsliding. The spatial distribution of soil depth, a strong control on local landsliding, is predicted from a process-based model. Because of its common availability, daily rainfall data were used to drive the model. Topographic data were derived from digitized 1 : 24 000 US Geological Survey contour maps. Analysis of the landslides shows that 97 occurred in 1955, 37 in 1982 and five in 1998, although the heaviest rainfall was in 1982. Furthermore, intensity-duration analysis of available daily and hourly rainfall from the closest raingauges does not discriminate those three storms from others that did not generate failures. We explore the question of whether a mechanistic modelling approach is better able to identify landslide-producing storms. Landslide and soil production parameters were fixed from studies elsewhere. Four hydrologic parameters characterizing the saturated hydraulic conductivity of the soil and underlying bedrock and its decline with depth were first calibrated on the 1955 landslide record. Success was characterized as the most number of actual landslides predicted with the least amount of total area predicted to be unstable. Because landslide area was consistently overpredicted, a threshold catchment area of predicted slope instability was used to define whether a rainstorm was a significant landslide producer. Many combinations of the four hydrological parameters performed equally well I-or the 1955 event, but only one combination successfully identified the 1982 storm as the only landslide-producing storm during the period 1980-86. Application of this parameter combination to the entire 45 year record successfully identified the three events, but also predicted that two other landslide-producing events should have occurred. This performance is significantly better than the empirical intensity-duration threshold approach, but requires considerable calibration effort. Overprediction of instability, both for storms that produced landslides and for non-producing storms, appears to arise from at least four causes: (1) coarse rainfall data time scale and inability to document short rainfall bursts and predict pressure wave response; (2) absence of local rainfall data; (3) legacy effect of previous landslides; and (4) inaccurate topographic and soil property data. Greater resolution of spatial and rainfall data, as well as topographic data, coupled with systematic documentation of landslides to create time series to test models, should lead to significant improvements in shallow landslides forecasting. Copyright (C) 2003 John Wiley Sons, Ltd. C1 Univ Calif Berkeley, Dept Earth & Planetary Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Reg Climate Ctr, Berkeley, CA 94720 USA. RP Dietrich, WE (reprint author), Univ Calif Berkeley, Dept Earth & Planetary Sci, 383 McCone Hall, Berkeley, CA 94720 USA. RI Miller, Norman/E-6897-2010 NR 90 TC 109 Z9 119 U1 2 U2 40 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0197-9337 J9 EARTH SURF PROC LAND JI Earth Surf. Process. Landf. PD AUG PY 2003 VL 28 IS 9 BP 925 EP 950 DI 10.1002/esp.470 PG 26 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 719VD UT WOS:000185225000001 ER PT J AU Lillard, RS AF Lillard, RS TI Relationships between metal-metal bonding and crystallographic pitting in hcp metals SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article ID ELECTRON-DENSITY DISTRIBUTION; MAXIMUM-ENTROPY METHOD; BERYLLIUM; PASSIVATION; DIFFRACTION; ALLOYS; ZINC AB The orientation dependence of pit propagation in single-crystal beryllium (Be) is compared to observations for single-crystal zinc (Zn). Pits formed on the prism planes of both Be and Zn were characterized by interiors which had crystallographically oriented, parallel plates of unattacked material. In Be, the orientation of the unattacked material had a 90degrees asymmetry with respect to those formed in Zn. To explain this difference, the electron density distribution for low index planes in Be and Zn was analyzed. A conceptual model for crystallographic pit propagation that considers the role of orientation dependent metal-metal bonding is introduced. (C)' 2003 The Electrochemical Society. C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Mat Corros & Environm Effects Lab, Los Alamos, NM 87545 USA. RP Lillard, RS (reprint author), Los Alamos Natl Lab, Div Mat Sci & Technol, Mat Corros & Environm Effects Lab, POB 1663, Los Alamos, NM 87545 USA. NR 11 TC 14 Z9 14 U1 1 U2 2 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 1099-0062 J9 ELECTROCHEM SOLID ST JI Electrochem. Solid State Lett. PD AUG PY 2003 VL 6 IS 8 BP B29 EP B31 DI 10.1149/1.1588113 PG 3 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 696KN UT WOS:000183886200007 ER PT J AU Mendes, N Winkelmann, FC Lamberts, R Philippi, PC AF Mendes, N Winkelmann, FC Lamberts, R Philippi, PC TI Moisture effects on conduction loads SO ENERGY AND BUILDINGS LA English DT Article DE conduction; hygroscopic; moisture AB The effects of moisture on sensible and latent conduction loads are shown by using a heat and mass transfer model with variable material properties, under varying boundary conditions. This model was then simplified to reduce calculation time and used to predict conduction peak load (CPL) and yearly integrated wall conduction heat flux (YHF) in three different cities: Singapore (hot/humid), Seattle (cold/humid) and Phoenix (hot/dry). The room air temperature and relative humidity were calculated with the building energy simulation program DOE-2.1E. The materials studied were aerated cellular concrete (ACC), brick (BRK), lime mortar (LMT) and wood. It is shown that the effects of moisture can be very significant and that simplified mathematical models can reduce the calculation time with varying effects on accuracy. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Pontificial Catolic Univ Parana, Dept Mech Engn, Thermal Syst Lab, BR-80215901 Curitiba, Parana, Brazil. Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Simulat Res Grp, Berkeley, CA 94720 USA. Univ Fed Santa Catarina, BR-88040900 Florianopolis, SC, Brazil. RP Mendes, N (reprint author), Pontificial Catolic Univ Parana, Dept Mech Engn, Thermal Syst Lab, BR-80215901 Curitiba, Parana, Brazil. RI Lamberts, Roberto/F-9756-2013; Philippi, Paulo/I-4972-2014 OI Lamberts, Roberto/0000-0001-6801-671X; Philippi, Paulo/0000-0003-2945-3356 NR 21 TC 55 Z9 59 U1 2 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7788 J9 ENERG BUILDINGS JI Energy Build. PD AUG PY 2003 VL 35 IS 7 BP 631 EP 644 AR PII S0378-7788(02)00171-8 PG 14 WC Construction & Building Technology; Energy & Fuels; Engineering, Civil SC Construction & Building Technology; Energy & Fuels; Engineering GA 691CQ UT WOS:000183587600001 ER PT J AU Shaughnessy, DA Nitsche, H Booth, CH Shuh, DK Waychunas, GA Wilson, RE Gill, H Cantrell, KJ Serne, RJ AF Shaughnessy, DA Nitsche, H Booth, CH Shuh, DK Waychunas, GA Wilson, RE Gill, H Cantrell, KJ Serne, RJ TI Molecular interfacial reactions between Pu(VI) and manganese oxide minerals manganite and hausmannite SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID FINE-STRUCTURE SPECTROSCOPY; SURFACE COMPLEXATION MODEL; PLUTONIUM IONS; ADSORPTION; SORPTION; HEMATITE; URANIUM(VI); KINETICS; FERRIHYDRITE; CHEMISTRY AB The sorption of Pu(VI) onto manganite (MnOOH) and hausmannite (Mn3O4) was studied as a function of time, solution pH, and initial plutonium concentration. Kinetic experiments indicate that the surface complexation of plutonium occurs over the first 24 h of contact with the mineral surface. The sorption increases with pH beginning at pH 3 until it reaches a maximum value of 100% at pH 8 (0.0011-0.84 mumol of Pu/m(2) of manganite and 0.98-1.2 2 mumol of Pu/m(2) of hausmannite) and then decreases over the pH range from 8 to 10. The ratio of solid to solution was 10 mg/mL for manganite experiments and 4 mg/mL for hausmannite samples. Carbonate was not excluded from the experiments. The amount of plutonium removed from the solution by the minerals is determined by a combination of factors including the plutonium solution species,the surface charge of the mineral, and the mineral surface area. X-ray absorption fine structure taken at the Pu L-III edge were compared to plutonium standard spectra and showed that Pu(VI) was reduced to Pu(IV) after contact with the minerals. Plutonium sorption to the mineral surface is consistent with an inner-sphere configuration, and PuO2 evidence of PuO2 precipitation is observed. The reduction and complexation of Pu(VI) by manganese minerals has direct implications on possible migration of Pu(VI) species in the environment. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Nitsche, H (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. EM hnitsche@lbl.gov RI Wilson, Richard/H-1763-2011; Booth, Corwin/A-7877-2008 OI Wilson, Richard/0000-0001-8618-5680; NR 50 TC 46 Z9 53 U1 6 U2 55 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X EI 1520-5851 J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD AUG 1 PY 2003 VL 37 IS 15 BP 3367 EP 3374 DI 10.1021/es025989z PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 707GF UT WOS:000184501900042 PM 12966983 ER PT J AU Borde, AB Thom, RM Rumrill, S Miller, LM AF Borde, AB Thom, RM Rumrill, S Miller, LM TI Geospatial habitat change analysis in Pacific Northwest Coastal estuaries SO ESTUARIES LA English DT Article ID ZOSTERA-JAPONICA ASCHERS; SALT-MARSHES; WILLAPA BAY; WASHINGTON; MANAGEMENT; ACCRETION; PATTERNS; MEADOWS; OREGON; FUTURE AB We assessed historical changes in the location and amount of potential estuarine habitat in three of the four largest coastal estuaries in the United States Pacific Northwest (Grays Harbor, Willapa Bay, and Coos Bay) as part of the Pacific Northwest Coastal Ecosystem Regional Study (PNCERS). To accomplish the historical assessment, navigation charts, hydrographic survey data, maps, and published descriptions were used to gain information on the location of the shoreline, bathymetry, and vegetated habitats, which were then digitized and subjected to geospatial analysis using a geographic information system (GIS). We used present-day elevational boundaries for marshes, flats, and eelgrass meadows to help define habitat areas where they were not indicated on historical maps. The analysis showed that tidal flats have decreased in all study areas, potential eelgrass, Zostera marina L., habitat has increased in Grays Harbor and Willapa Bay and decreased slightly in Coos Bay, tidal wetland area has declined in all three coastal estuaries with increases in localized areas due to filling and sedimentation, and dramatic changes have occurred at the mouths of Grays Harbor and Willapa Bay. These data illustrate that direct physical alteration (filling and diking) has resulted in large changes to habitats. Forest practices in the watershed, as well as variation in climatic factors and oceanographic processes, may also have contributed to changes. The information provides more evidence for managing estuarine habitats in the region and employing historical templates to plan habitat restoration in the future. C1 Battelle Marine Sci Lab, Sequim, WA 98382 USA. S Slough Natl Estuarine Res Reserve, Charleston, OR 97420 USA. RP Borde, AB (reprint author), Battelle Marine Sci Lab, 1529 W Sequim Bay Rd, Sequim, WA 98382 USA. EM amy.borde@pnl.gov NR 64 TC 33 Z9 33 U1 4 U2 26 PU ESTUARINE RESEARCH FEDERATION PI PORT REPUBLIC PA 2018 DAFFODIL, PO BOX 510, PORT REPUBLIC, MD 20676 USA SN 0160-8347 J9 ESTUARIES JI Estuaries PD AUG PY 2003 VL 26 IS 4B BP 1104 EP 1116 DI 10.1007/BF02803367 PG 13 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 732JB UT WOS:000185936100010 ER PT J AU Thom, RM Borde, AB Rumrill, S Woodruff, DL Williams, GD Southard, JA Sargeant, SL AF Thom, RM Borde, AB Rumrill, S Woodruff, DL Williams, GD Southard, JA Sargeant, SL TI Factors influencing spatial and annual variability in eelgrass (Zostera marina L.) meadows in Willapa Bay, Washington, and Coos Bay, Oregon, estuaries SO ESTUARIES LA English DT Article ID SUBMERSED AQUATIC VEGETATION; PACIFIC-NORTHWEST ESTUARIES; CENTRAL-PUGET-SOUND; TEMPORAL PATTERNS; STANDING-STOCK; SEAGRASS BEDS; HABITAT; COASTAL; US; PHOTOSYNTHESIS AB Environmental factors that influence annual variability and spatial differences (within and between estuaries) in eelgrass meadows (Zostera marina L.) were examined within Willapa Bay, Washington, and Coos Bay, Oregon, over a period of 4 years (1998-2001). A suite of eelgrass metrics were recorded annually at field sites that spanned the estuarine gradient from the marine-dominated to mesohaline region of each estuary. Plant density (shoots m(-2)) of eelgrass was positively correlated with summer estuarine salinity and inversely correlated with water temperature gradients in the estuaries. Eelgrass density, biomass, and the incidence of flowering plants all increased substantially in Willapa Bay, and less so in Coos Bay, over the duration of the study. Warmer winters and cooler summers associated with the transition from El Nino to La Nina ocean conditions during the study period corresponded with this increase in eelgrass abundance and flowering. Large-scale changes in climate and nearshore ocean conditions may exert a strong regional influence on eelgrass abundance that can vary annually by as much as 700% in Willapa Bay. Lower levels of annual variability observed in Coos Bay may be due to the stronger and more direct influence of the nearshore Pacific Ocean on the Coos Bay study sites. The results suggest profound effects of climate variation on the abundance and flowering of eelgrass in Pacific Northwest coastal estuaries. C1 Battelle Marine Sci Lab, Sequim, WA 98382 USA. S Slough Natl Estuarine Res Reserve, Charleston, OR 97420 USA. RP Thom, RM (reprint author), Battelle Marine Sci Lab, 1529 W Sequim Bay Rd, Sequim, WA 98382 USA. EM ron.thom@pnl.gov NR 59 TC 37 Z9 37 U1 1 U2 27 PU ESTUARINE RESEARCH FEDERATION PI PORT REPUBLIC PA 2018 DAFFODIL, PO BOX 510, PORT REPUBLIC, MD 20676 USA SN 0160-8347 J9 ESTUARIES JI Estuaries PD AUG PY 2003 VL 26 IS 4B BP 1117 EP 1129 DI 10.1007/BF02803368 PG 13 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 732JB UT WOS:000185936100011 ER PT J AU Ding, HF Wulfhekel, W Schlickum, U Kirschner, J AF Ding, HF Wulfhekel, W Schlickum, U Kirschner, J TI Spin-polarized vacuum tunneling at small gap widths SO EUROPHYSICS LETTERS LA English DT Article ID CLOSURE DOMAIN PATTERN; HIGH-RESOLUTION; JUNCTIONS; MAGNETORESISTANCE; MICROSCOPY; FERROMAGNETS; DEPENDENCE; ELECTRONS; BARRIER; SURFACE AB We studied spin-polarized tunneling through a vacuum barrier using spin-polarized scanning tunneling microscopy on Co(0001). By varying the tip-to-sample distance in a controlled way, the tunneling magnetoresistance, i.e., the tunneling current asymmetry for parallel and antiparallel configuration of tip and sample magnetization, was measured as a function of the gap width. At large gap widths the asymmetry is constant. At gap widths below approximate to 4.5 Angstrom, a drop of the asymmetry was found in contrast to predictions of the Julliere model. The drop of the current asymmetry in spin-polarized tunneling is found to correlate with drop of the imaginary electron momentum inside the barrier and we compare our experimental results with the predictions of the Slonczewski model. C1 Max Planck Inst Mikrostrukturphys, D-06120 Halle Saale, Germany. RP Ding, HF (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Wulfhekel, Wulf/E-2533-2011; Ding, haifeng/B-4221-2010 OI Wulfhekel, Wulf/0000-0001-6890-643X; Ding, haifeng/0000-0001-7524-0779 NR 39 TC 8 Z9 8 U1 0 U2 3 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD AUG PY 2003 VL 63 IS 3 BP 419 EP 425 DI 10.1209/epl/i2003-00549-4 PG 7 WC Physics, Multidisciplinary SC Physics GA 706CV UT WOS:000184435200016 ER PT J AU Cavadini, N Schneider, M Allenspach, P Canfield, PC Bourges, P AF Cavadini, N Schneider, M Allenspach, P Canfield, PC Bourges, P TI Magnetic-field dependence of the magnetic excitations in ordered HoNi2B2C SO EUROPHYSICS LETTERS LA English DT Article ID SUPERCONDUCTING GAP; CRYSTAL-FIELD; BOROCARBIDES; STATE; SPECTROSCOPY; TRANSITIONS; MODEL AB The effect of an external magnetic field H on the magnetic excitations in ordered HoNi2B2C is investigated by inelastic neutron scattering on single crystals for the first time. A Zeeman-like renormalization of the magnetic excitations is observed at fixed T = 2 K and H parallel to [1, 1, 0] up to H = 5 T. Above H similar to 1.1 T the renormalization occurs linearly, following the expectation for the Ho3+ crystal electric-field levels at finite fields. However, in the range 0 < H < 1.1 T clear discontinuities mark the successive metamagnetic transitions reported for the ground state of the title compound. The comparison of the magnetic excitations between the antiferromagnetic (H < 0.4 T), helicoidal (0.4 &LE; H < 1.1 T) and ferromagnetic (H greater than or equal to 1.1 T) ground state allows, by first principles, the determination of the leading exchange interactions between the rare-earth ions. The quantitative results are put into the context of recent theoretical models. C1 Swiss Fed Inst Technol, Neutron Scattering Lab, CH-5232 Villigen, Switzerland. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Iowa State Univ Sci & Technol, Ames Lab, Dept Phys & Astron, Ames, IA 50011 USA. CEA Saclay, CNRS, Lab Leon Brillouin, F-91191 Gif Sur Yvette, France. RP Cavadini, N (reprint author), Swiss Fed Inst Technol, Neutron Scattering Lab, CH-5232 Villigen, Switzerland. RI Canfield, Paul/H-2698-2014 NR 24 TC 1 Z9 1 U1 1 U2 3 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD AUG PY 2003 VL 63 IS 4 BP 597 EP 602 DI 10.1209/epl/i2003-00568-7 PG 6 WC Physics, Multidisciplinary SC Physics GA 709GU UT WOS:000184618100019 ER PT J AU Webster, JR Mulholland, PJ Tank, JL Valett, HM Dodds, WK Peterson, BJ Bowden, WB Dahm, CN Findlay, S Gregory, SV Grimm, NB Hamilton, SK Johnson, SL Marti, E McDowell, WH Meyer, JL Morrall, DD Thomas, SA Wollheim, WM AF Webster, JR Mulholland, PJ Tank, JL Valett, HM Dodds, WK Peterson, BJ Bowden, WB Dahm, CN Findlay, S Gregory, SV Grimm, NB Hamilton, SK Johnson, SL Marti, E McDowell, WH Meyer, JL Morrall, DD Thomas, SA Wollheim, WM TI Factors affecting ammonium uptake in streams - an inter-biome perspective SO FRESHWATER BIOLOGY LA English DT Review DE biome; metabolism; nitrogen; stable isotope; transient storage ID DISSOLVED ORGANIC NITROGEN; TRANSIENT STORAGE MODEL; OXYGEN CHANGE TECHNIQUE; DESERT STREAM; HEADWATER STREAMS; SOLUTE TRANSPORT; HYPORHEIC ZONE; SURFACE-WATER; FOREST STREAM; UPTAKE LENGTH AB 1. The Lotic Intersite Nitrogen eXperiment (LINX) was a coordinated study of the relationships between North American biomes and factors governing ammonium uptake in streams. Our objective was to relate inter-biome variability of ammonium uptake to physical, chemical and biological processes. 2. Data were collected from 11 streams ranging from arctic to tropical and from desert to rainforest. Measurements at each site included physical, hydraulic and chemical characteristics, biological parameters, whole-stream metabolism and ammonium uptake. Ammonium uptake was measured by injection of N-15-ammonium and downstream measurements of N-15-ammonium concentration. 3. We found no general, statistically significant relationships that explained the variability in ammonium uptake among sites. However, this approach does not account for the multiple mechanisms of ammonium uptake in streams. When we estimated biological demand for inorganic nitrogen based on our measurements of in-stream metabolism, we found good correspondence between calculated nitrogen demand and measured assimilative nitrogen uptake. 4. Nitrogen uptake varied little among sites, reflecting metabolic compensation in streams in a variety of distinctly different biomes (autotrophic production is high where allochthonous inputs are relatively low and vice versa). 5. Both autotrophic and heterotrophic metabolism require nitrogen and these biotic processes dominate inorganic nitrogen retention in streams. Factors that affect the relative balance of autotrophic and heterotrophic metabolism indirectly control inorganic nitrogen uptake. C1 Virginia Polytech Inst & State Univ, Dept Biol, Blacksburg, VA 24061 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Notre Dame, Dept Biol Sci, Notre Dame, IN 46556 USA. Kansas State Univ, Div Biol, Manhattan, KS 66506 USA. Marine Biol Lab, Ctr Ecosyst, Woods Hole, MA 02543 USA. Univ Vermont, Sch Nat Resources, Burlington, VT 05405 USA. Univ New Mexico, Dept Biol, Albuquerque, NM 87131 USA. Inst Ecosyst Studies, Millbrook, NY 12545 USA. Oregon State Univ, Dept Fisheries & Wildlife, Corvallis, OR 97331 USA. Arizona State Univ, Dept Biol, Tempe, AZ USA. Michigan State Univ, Kellogg Biol Stn, Hickory Corners, MI 49060 USA. US Forest Serv, USDA, PNW Res Stn, Corvallis, OR USA. CSIC, Ctr Estudis Avancats Blanes, Blanes, Girona, Spain. Univ New Hampshire, Dept Nat Resources, Durham, NH 03824 USA. Univ Georgia, Inst Ecol, Athens, GA 30602 USA. Procter & Gamble Co, Dept Environm Sci, Cincinnati, OH USA. EcoMetr Inc, Pendleton, OR USA. Univ New Hampshire, Complex Syst Res Ctr, Durham, NH 03824 USA. RP Webster, JR (reprint author), Virginia Polytech Inst & State Univ, Dept Biol, Blacksburg, VA 24061 USA. EM jwebster@vt.edu RI McDowell, William/E-9767-2010; Mulholland, Patrick/C-3142-2012; Grimm, Nancy/D-2840-2009; Marti, Eugenia/J-9146-2012; Bowden, William/J-9219-2014; Hamilton, Stephen/N-2979-2014 OI McDowell, William/0000-0002-8739-9047; Grimm, Nancy/0000-0001-9374-660X; Marti, Eugenia/0000-0002-6910-4874; Hamilton, Stephen/0000-0002-4702-9017 NR 101 TC 154 Z9 163 U1 6 U2 70 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0046-5070 EI 1365-2427 J9 FRESHWATER BIOL JI Freshw. Biol. PD AUG PY 2003 VL 48 IS 8 BP 1329 EP 1352 DI 10.1046/j.1365-2427.2003.01094.x PG 24 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 702AY UT WOS:000184203500004 ER PT J AU Cottrell, RL Antony, A Logg, C Navratil, J AF Cottrell, RL Antony, A Logg, C Navratil, J TI iGrid2002 demonstration: bandwidth from the low lands SO FUTURE GENERATION COMPUTER SYSTEMS LA English DT Article; Proceedings Paper CT 3rd Biennial International Grid Application-Driven Testbed Conference (iGrid 2002) CY SEP 23-26, 2002 CL AMSTERDAM, NETHERLANDS DE iGrid2002; high-throughput; measurement tools; monitoring; networks; tuning; TCP AB We report on a demonstration of several complementary high-performance end-to-end active network throughput measurement tools. These include: the PingWorld Java applet that displays the Round Trip Time (RTT) and losses to sites around the world from the user's host; the multi-path analysis tool that visualizes common paths from traceroutes to selected hosts; the IEPM high-performance BandWidth monitoring toolkit which gives achievable throughput for several types of TCP data transfer applications; and the Available Bandwidth Estimation (ABWE) tool that reports in real-time the available bandwidth to several paths within the range from Mbits/s to Gbits/s. We also demonstrated sending high-speed data from 4 hosts at iGrid2002 to over 30 hosts in 10 countries to simulate a high energy physics experiment distributing data to collaborators. The demonstration utilized the high-speed, long latency, trans-Atlantic network set up for iGrid2002 in Amsterdam during September 2002. Published by Elsevier Science B.V. C1 Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. Natl Inst Nucl & High Energy Phys, NIKHEF, NL-1009 SJ Amsterdam, Netherlands. RP Cottrell, RL (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. 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 0167-739X J9 FUTURE GENER COMP SY JI Futur. Gener. Comp. Syst. PD AUG PY 2003 VL 19 IS 6 BP 825 EP 837 DI 10.1016/S0167-739X(03)00063-3 PG 13 WC Computer Science, Theory & Methods SC Computer Science GA 709ZR UT WOS:000184656900004 ER PT J AU Breckenridge, A Pierson, L Sanielevici, S Welling, J Keller, R Woessner, U Schulze, J AF Breckenridge, A Pierson, L Sanielevici, S Welling, J Keller, R Woessner, U Schulze, J TI Distributed, on-demand, data-intensive and collaborative simulation analysis SO FUTURE GENERATION COMPUTER SYSTEMS LA English DT Article; Proceedings Paper CT 3rd Biennial International Grid Application-Driven Testbed Conference (iGrid 2002) CY SEP 23-26, 2002 CL AMSTERDAM, NETHERLANDS DE compute; visualize; collaborate; data-intensive; simulation analysis; bioinformatics applications AB Distributed, on-demand, data-intensive, and collaborative simulation analysis tools are being developed by an international team to solve real problems such as bioinformatics applications. The project consists of three distinct focuses: compute, visualize, and collaborate. Each component utilizes software and hardware that performs across the International Grid. Computers in North America, Asia, and Europe are working on a common simulation programs. The results are visualized in a multi-way 3D visualization collaboration session where additional compute requests can be submitted in real-time. Navigation controls and data replication issues are addressed and solved with a scalable solution. Published by Elsevier B.V. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Pittsburgh Supercomp Ctr, Pittsburgh, PA USA. Ctr High Performance Comp, Stuttgart, Germany. RP Breckenridge, A (reprint author), Sandia Natl Labs, Albuquerque, NM 87185 USA. NR 9 TC 11 Z9 12 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-739X J9 FUTURE GENER COMP SY JI Futur. Gener. Comp. Syst. PD AUG PY 2003 VL 19 IS 6 BP 849 EP 859 DI 10.1016/S0167-739X(03)00065-7 PG 11 WC Computer Science, Theory & Methods SC Computer Science GA 709ZR UT WOS:000184656900006 ER PT J AU Karonis, NT Papka, ME Binns, J Bresnahan, J Insley, JA Jones, D Link, JM AF Karonis, NT Papka, ME Binns, J Bresnahan, J Insley, JA Jones, D Link, JM TI High-resolution remote rendering of large datasets in a collaborative environment SO FUTURE GENERATION COMPUTER SYSTEMS-THE INTERNATIONAL JOURNAL OF ESCIENCE LA English DT Article; Proceedings Paper CT 3rd Biennial International Grid Application-Driven Testbed Conference (iGrid 2002) CY SEP 23-26, 2002 CL AMSTERDAM, NETHERLANDS DE MPI; Globus Toolkit; GridFTP; Access Grid; MPICH-G2 AB In a time when computational and data resources are distributed around the globe, users need to interact with these resources and each other easily and efficient. The Grid, by definition, represents a connection of distributed resources that can be used regardless of the user's location. We have built a prototype visualization system using the Globus Toolkit, MPICH-G2, and the Access Grid in order to explore how future scientific collaborations may occur over the Grid. We describe our experience in demonstrating our system at iGrid2002, where the United States and the Netherlands were connected via a high-latency, high-bandwidth network. In particular, we focus on issues related to a Grid-based application that couples a collaboration component (including a user interface to the Access Grid) with a high-resolution remote rendering component. Published by Elsevier Science B.V. C1 No Illinois Univ, Dept Comp Sci, De Kalb, IL 60115 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Univ Chicago, Dept Comp Sci, Chicago, IL 60637 USA. RP No Illinois Univ, Dept Comp Sci, De Kalb, IL 60115 USA. EM karonis@niu.edu; papka@mcs.anl.gov NR 11 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-739X EI 1872-7115 J9 FUTURE GENER COMP SY JI Futur. Gener. Comp. Syst. PD AUG PY 2003 VL 19 IS 6 BP 909 EP 917 DI 10.1016/S0167-739X(03)00070-0 PG 9 WC Computer Science, Theory & Methods SC Computer Science GA 709ZR UT WOS:000184656900011 ER PT J AU Allcock, W Bresnahan, J Bunn, J Hegde, S Insley, J Kettimuthu, R Newman, H Ravot, S Rimovsky, T Steenberg, C Winkler, L AF Allcock, W Bresnahan, J Bunn, J Hegde, S Insley, J Kettimuthu, R Newman, H Ravot, S Rimovsky, T Steenberg, C Winkler, L TI Grid-enabled particle physics event analysis: experiences using a 10 Gb, high-latency network for a high-energy physics application SO FUTURE GENERATION COMPUTER SYSTEMS-THE INTERNATIONAL JOURNAL OF ESCIENCE LA English DT Article; Proceedings Paper CT 3rd Biennial International Grid Application-Driven Testbed Conference (iGrid 2002) CY SEP 23-26, 2002 CL AMSTERDAM, NETHERLANDS DE networks; DataGrid; congestion avoidance; 10 GigE; Web100 AB This paper examines issues encountered attempting to exploit a high-bandwidth, high-latency link in support of a high-energy physics (HEP) analysis application. The primary issue was that the TCP additive increase/multiplicative decrease (AIMD) algorithm is not suitable for "long fat networks". While this is a known problem, the magnitude of the impact on application performance was much greater than anticipated. We were able to overcome much of the impact, by altering the AIMD coefficients. Such an approach, of course, is non-TCP compliant, and there was insufficient time to test the network friendliness of these modifications. Published by Elsevier Science B.V. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. CALTECH, Pasadena, CA 91125 USA. Natl Ctr Supercomp Applicat, Urbana, IL USA. IIT, Chicago, IL 60616 USA. Ohio State Univ, Columbus, OH 43210 USA. RP Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. EM allcock@mcs.anl.gov NR 16 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-739X EI 1872-7115 J9 FUTURE GENER COMP SY JI Futur. Gener. Comp. Syst. PD AUG PY 2003 VL 19 IS 6 BP 983 EP 997 DI 10.1016/S0167-739X(03)00076-1 PG 15 WC Computer Science, Theory & Methods SC Computer Science GA 709ZR UT WOS:000184656900017 ER PT J AU Fischle, W Wang, YM Jacobs, SA Kim, YC Allis, CD Khorasanizadeh, S AF Fischle, W Wang, YM Jacobs, SA Kim, YC Allis, CD Khorasanizadeh, S TI Molecular basis for the discrimination of repressive methyl-lysine marks in histone H3 bv Polvcomb and HP1 chromodomains SO GENES & DEVELOPMENT LA English DT Article DE polycomb; HP1; heterochromatin; histone H3; lysine methylation; epigenetic ID POLYCOMB GROUP PROTEINS; CHROMO DOMAIN; METHYLTRANSFERASE ACTIVITY; GROUP-COMPLEXES; IN-VIVO; DROSOPHILA; HETEROCHROMATIN; BINDING; ENHANCER; ESTABLISHMENT AB On the histone H3 tail, Lys 9 and Lys 27 are both methylation sites associated with epigenetic repression, and reside within a highly related sequence motif ARKS. Here we show that the chromodomain proteins Polycomb (Pc) and HP1 (heterochromatin protein 1) are highly discriminatory for binding to these sites in vivo and in vitro. In Drosophila S2 cells, and on polytene chromosomes, methyl-Lys 27 and Pc are both excluded from areas that are enriched in methyl-Lys 9 and HP1. Swapping of the chromodomain regions of Pc and HP1 is sufficient for switching the nuclear localization patterns of these factors, indicating a role for their chromodomains in both target site binding and discrimination. To better understand the molecular basis for the selection of methyl-lysine binding sites, we solved the 1.8 Angstrom structure of the Pc chromodomain in complex with a H3 peptide bearing trimethyl-Lys 27, and compared it with our previously determined structure of the HP1 chromodomain in complex with a H3 peptide bearing trimethyl-Lys 9. The Pc chromodomain distinguishes its methylation target on the H3 tail via an extended recognition groove that binds five additional residues preceding the ARKS motif. C1 Univ Virginia Hlth Syst, Dept Biochem & Mol Genet, Charlottesville, VA 22908 USA. Rockefeller Univ, Lab Chromatin Biol, New York, NY 10021 USA. Argonne Natl Lab, Struct Biol Ctr, Biosci Div, Argonne, IL 60439 USA. RP Fischle, W (reprint author), Univ Virginia Hlth Syst, Dept Biochem & Mol Genet, Charlottesville, VA 22908 USA. FU NIGMS NIH HHS [GM53512, GM63959, R01 GM063959, R37 GM053512] NR 49 TC 604 Z9 622 U1 0 U2 18 PU COLD SPRING HARBOR LAB PRESS, PUBLICATIONS DEPT PI WOODBURY PA 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2924 USA SN 0890-9369 J9 GENE DEV JI Genes Dev. PD AUG 1 PY 2003 VL 17 IS 15 BP 1870 EP 1881 DI 10.1101/gad.110503 PG 12 WC Cell Biology; Developmental Biology; Genetics & Heredity SC Cell Biology; Developmental Biology; Genetics & Heredity GA 707VX UT WOS:000184531500009 PM 12897054 ER PT J AU Brown, GR Bassoni, DL Gill, GP Fontana, JR Wheeler, NC Megraw, RA Davis, MF Sewell, MM Tuskan, GA Neale, DB AF Brown, GR Bassoni, DL Gill, GP Fontana, JR Wheeler, NC Megraw, RA Davis, MF Sewell, MM Tuskan, GA Neale, DB TI Identification of quantitative trait loci influencing wood property traits in loblolly pine (Pinus taeda L.). III. QTL verification and candidate gene mapping SO GENETICS LA English DT Article ID OUTBRED PEDIGREE; ARABINOGALACTAN-PROTEIN; LINKAGE MAPS; FRUIT SIZE; POPULATION; TOMATO; XYLEM; CONSTRUCTION; MARKERS; SAMPLES AB A long-term series of experiments to map QTL influencing wood property traits in loblolly pine has been completed. These experiments were designed to identify and subsequently verify QTL in multiple genetic backgrounds, environments, and growing seasons. Verification of QTL is necessary to substantiate a biological basis for observed marker-trait associations, to provide precise estimates of the magnitude of QTL effects, and to predict QTL expression at a given age or in a particular environment. Verification was based on the repeated detection of QTL among populations, as well as among multiple growing seasons for each population. Temporal stability of QTL was moderate, with approximately half being detected in multiple seasons. Fewer QTL were common to different populations, but the results are nonetheless encouraging for restricted applications of marker-assisted selection. QTL from larger populations accounted for less phenotypic variation than QTL detected in smaller populations, emphasizing the need for experiments employing much larger families. Additionally, 18 candidate genes related to lignin biosynthesis and cell wall structure were mapped genetically. Several candidate genes colocated with wood property QTL; however, these relationships Must be verified in future experiments. C1 Univ Calif Davis, Dept Environm Hort, USDA Forest Serv, Pacific SW Res Stn, Davis, CA 95616 USA. USDA Forest Serv, Pacific SW Res Stn, Inst Forest Genet, Davis, CA 95616 USA. Weyerhaeuser Co, Weyerhaeuser Tech Ctr, Tacoma, WA 98477 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Oak Ridge Natl Lab, Environm Sci Div, Oak Ridge, TN 37831 USA. RP Neale, DB (reprint author), Univ Calif Davis, Dept Environm Hort, USDA Forest Serv, Pacific SW Res Stn, 1 Shields Ave, Davis, CA 95616 USA. RI Tuskan, Gerald/A-6225-2011; OI Tuskan, Gerald/0000-0003-0106-1289; davis, mark/0000-0003-4541-9852 NR 39 TC 73 Z9 83 U1 2 U2 11 PU GENETICS PI BALTIMORE PA 428 EAST PRESTON ST, BALTIMORE, MD 21202 USA SN 0016-6731 J9 GENETICS JI Genetics PD AUG PY 2003 VL 164 IS 4 BP 1537 EP 1546 PG 10 WC Genetics & Heredity SC Genetics & Heredity GA 720EF UT WOS:000185248000026 PM 12930758 ER PT J AU Lacape, JM Nguyen, TB Thibivilliers, S Bojinov, B Courtois, B Cantrell, RG Burr, B Hau, B AF Lacape, JM Nguyen, TB Thibivilliers, S Bojinov, B Courtois, B Cantrell, RG Burr, B Hau, B TI A combined RFLP-SSR-AFLP map of tetraploid cotton based on a Gossypium hirsutum x Gossypium barbadense backcross population SO GENOME LA English DT Article DE cotton; genetic mapping; RFLP; microsatellite; AFLP ID THEOBROMA-CACAO L; LINKAGE MAP; ALLOTETRAPLOID COTTON; LYCOPERSICON-ESCULENTUM; POLYPLOID FORMATION; REPETITIVE DNA; MARKERS; INTROGRESSION; CHROMOSOMES; SEGREGATION AB An interspecific Gossypium hirsutum x Gossypium barbadense backcross population of 75 BC1 plants was evaluated for 1014 markers. The map consists of 888 loci, including 465 AFLPs, 229 SSRs, 192 RFLPs, and 2 morphological markers, ordered in 37 linkage groups that represent most if not all of the 26 chromosomes, altogether spanning 4400 cM Loci were not evenly distributed over linkage groups, and 18 of the 26 long groups had a single dense region. This paper proposes a partially revised list of the 13 pairs of homoeologous A/D chromosomes of the 2n = 4x = 52 tetraploid cotton genome. The major revisions, which involve the c3-c17, c4-c22, c5-D08, and c10-c20 homocologous pairs, are based on the mapping of 68 SSR and RFLP loci with a known chromosome assignment, as well as on comparative alignments with previously published G. hirsutum x G. barbadense maps. The overall congruency in the locus orders and distances of common SSR and RFLP loci in these maps allows for an estimation of the consensus length that reaches a minimum of 5500 cM, and is encouraging for future efforts aimed at developing an integrated map of cultivated cotton. The present map also provides a firm framework for precision mapping of Mendelian components of quantitative traits in cotton. C1 CIRAD, F-34398 Montpellier 5, France. Agr Univ Plovdiv, Dept Genet & Plant Breeding, Plovdiv 4000, Bulgaria. Cotton Inc, Cary, NC 27513 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Lacape, JM (reprint author), CIRAD, TA 70-03,Ave Agropolis, F-34398 Montpellier 5, France. RI Courtois, Brigitte/A-4004-2009; Lacape, Jean-Marc/B-4326-2008; Bojinov, Bojin/H-7820-2016 OI Courtois, Brigitte/0000-0003-2118-7102; Bojinov, Bojin/0000-0002-5497-5757 NR 58 TC 147 Z9 188 U1 0 U2 16 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0831-2796 J9 GENOME JI Genome PD AUG PY 2003 VL 46 IS 4 BP 612 EP 626 DI 10.1139/G03-050 PG 15 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 711RR UT WOS:000184755300011 PM 12897870 ER PT J AU Gu, BH Brooks, SC Roh, Y Jardine, PM AF Gu, BH Brooks, SC Roh, Y Jardine, PM TI Geochemical reactions and dynamics during titration of a contaminated groundwater with high uranium, aluminum, and calcium SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID LASER-INDUCED FLUORESCENCE; MAGNESIAN CALCITES; AQUEOUS-SOLUTIONS; SORPTION; ADSORPTION; HYDROXIDE; URANYL; IRON; DISSOLUTION; SYSTEM AB This study investigated possible geochemical reactions during titration of a contaminated groundwater with a low pH but high concentrations of aluminum, calcium, magnesium, manganese, and trace contaminant metals/radionuclides such as uranium, technetium, nickel, and cobalt. Both Na-carbonate and hydroxide were used as titrants, and a geochemical equilibrium reaction path model was employed to predict aqueous species and mineral precipitation during titration. Although the model appeared to be adequate to describe the concentration profiles of some metal cations, solution pH, and mineral precipitates, it failed to describe the concentrations of U during titration and its precipitation. Most U (as uranyl, UO22+) as well as Tc (as pertechnetate, TcO4-) were found to be sorbed and coprecipitated with amorphous Al and Fe oxyhydroxides at pH below similar to5.5, but slow desorption or dissolution of U and Tc occurred at higher pH values when Na2CO3 was used as the titrant. In general, the precipitation of major cationic species followed the order of Fe(OH)(3) and/or FeCo0.1(OH)(3.2), Al-4(OH)(10)SO4, MnCO3, CaCO3, conversion of Al-4(OH)(10)SO4 to Al(OH)(3,am), Mn(OH)(2), Mg(OH)(2), MgCO3, and Ca(OH)(2). The formation of mixed or double hydroxide phases of Ni and Co with Al and Fe oxyhydroxides was thought to be responsible for the removal of Ni and Co in solution. Results of this study indicate that, although the hydrolysis and precipitation of a single cation are known, complex reactions such as sorption/desorption, coprecipitation of mixed mineral phases, and their dissolution could occur simultaneously. These processes as well as the kinetic constraints must be considered in the design of the remediation strategies and modeling to better predict the activities of various metal species and solid precipitates during pre- and post-groundwater treatment practices. Copyright (C) 2003 Elsevier Ltd. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Gu, BH (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Brooks, Scott/B-9439-2012; Gu, Baohua/B-9511-2012 OI Brooks, Scott/0000-0002-8437-9788; Gu, Baohua/0000-0002-7299-2956 NR 59 TC 41 Z9 42 U1 4 U2 28 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 AUG PY 2003 VL 67 IS 15 BP 2749 EP 2761 DI 10.1016/S0016-7037(03)00097-8 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 705WD UT WOS:000184418200004 ER PT J AU Liu, CX Zachara, JM Smith, SC McKinley, JP Ainsworth, CC AF Liu, CX Zachara, JM Smith, SC McKinley, JP Ainsworth, CC TI Desorption kinetics of radiocesium from subsurface sediments at Hanford Site, USA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID CLAY-MINERALS; SELECTIVE SORPTION; CESIUM SORPTION; ILLITE; FIXATION; REVERSIBILITY; ADSORPTION; RETENTION; CATIONS; CS-137 AB The desorption of Cs-137(+) was investigated on sediments from the United States Hanford site. Pristine sediments and ones that were contaminated by the accidental release of alkaline Cs-137(+)-containing high level nuclear wastes (HLW, 2 x 10(6) to 6 x 10(6) pCi Cs-137(+)/g) were studied. The desorption of Cs-137(+), was measured in Na+, K+, Rb+, and NH(4)(+)electrolytes of variable concentration and pH, and in presence of a strong Cs+-specific sorbent (self-assembled monolayer on a mesoporous support, SAMMS). Cs-137(+) desorption from the HLW-contaminated Hanford sediments exhibited two distinct phases: an initial instantaneous release followed by a slow kinetic process. The extent of Cs-137(+) desorption increased with increasing electrolyte concentration and followed a trend of Rb+ greater than or equal to K+ > Na+ at circumneutral pH. This trend followed the respective selectivities of these cations for the sediment. The extent and rate of Cs-137(+) desorption was influenced by surface armoring, intraparticle diffusion, and the collapse of edge-interlayer sites in solutions containing K+, Rb+, or NH4+ Scanning electron microscopic analysis revealed HLW-induced precipitation of secondary aluminosilicates on the edges and basal planes of micaceous minerals that were primary Cs+ sorbents. The removal of these precipitates by acidified ammonium oxalate extraction significantly increased the long-term desorption rate and extent. X-ray microprobe analyses of Cs+-sorbed micas showed that the Cs-137(+) distributed not only on mica edges, but also within internal channels parallel to the basal plane, implying intraparticle diffusive migration of Cs-137(+). Controlled desorption experiments using Cs+-spiked pristine sediment indicated that the Cs-137(+) diffusion rate was fast in Na+-electrolyte, but much slower in the presence of K+ or Rb+, suggesting an effect of edge-interlayer collapse. An intraparticle diffusion model coupled with a two-site cation exchange model was used to interpret the experimental results. Model simulations suggested that about 40% of total sorbed Cs-137(+) was exchangeable, including equilibrium and kinetic desorbable pools. At pH 3, this ratio increased to 60-80%. The remainder of the sorbed Cs-137(+) was fixed or desorbed at much slower rate than our experiments could detect. Copyright (C) 2003 Elsevier Ltd. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Liu, CX (reprint author), Pacific NW Natl Lab, POB 999,MSIN K8-96, Richland, WA 99352 USA. RI Liu, Chongxuan/C-5580-2009 NR 35 TC 64 Z9 64 U1 3 U2 43 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 AUG PY 2003 VL 67 IS 16 BP 2893 EP 2912 DI 10.1016/S0016-7037(00)00267-9 PG 20 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 709DK UT WOS:000184609300001 ER PT J AU Hansel, CM Benner, SG Neiss, J Dohnalkova, A Kukkadapu, RK Fendorf, S AF Hansel, CM Benner, SG Neiss, J Dohnalkova, A Kukkadapu, RK Fendorf, S TI Secondary mineralization pathways induced by dissimilatory iron reduction of ferrihydrite under advective flow SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID CRYSTALLINE IRON(III) OXIDES; INSOLUBLE FE(III) OXIDE; HYDROUS FERRIC-OXIDE; MICROBIAL REDUCTION; SHEWANELLA-PUTREFACIENS; REDUCING BACTERIUM; AQUATIC SEDIMENTS; MAGNETITE FE3O4; TRANSFORMATION; DISSOLUTION AB Iron(hydr)oxides not only serve as potent sorbents and repositories for nutrients and contaminants but also provide a terminal electron acceptor for microbial respiration. The microbial reduction of Fe (hydr)oxides and the subsequent secondary solid-phase transformations will, therefore, have a profound influence on the biogeochemical cycling of Fe as well as associated metals. Here we elucidate the pathways and mechanisms of secondary mineralization during dissimilatory iron reduction by a common iron-reducing bacterium, Shewanella putrefaciens (strain CN32), of 2-line ferrihydrite under advective flow conditions. Secondary mineralization of ferrihydrite occurs via a coupled, biotic-abiotic pathway primarily resulting in the production of magnetite and goethite with minor amounts of green rust. Operating mineralization pathways are driven by competing abiotic reactions of bacterially generated ferrous iron with the ferrihydrite surface. Subsequent to the initial sorption of ferrous iron on ferrihydrite, goethite (via dissolution/reprecipitation) and/or magnetite (via solid-state conversion) precipitation ensues resulting in the spatial coupling of both goethite and magnetite with the ferrihydrite surface. The distribution of goethite and magnetite within the column is dictated, in large part, by flow-induced ferrous Fe profiles. While goethite precipitation occurs over a large Fe(II) concentration range, magnetite accumulation is only observed at concentrations exceeding 0.3 mmol/L (equivalent to 0.5 mmol Fe[II]/g ferrihydrite) following 16 d of reaction. Consequently, transport-regulated ferrous Fe profiles result in a progression of magnetite levels downgradient within the column. Declining microbial reduction over time results in lower Fe(II) concentrations and a subsequent shift in magnetite precipitation mechanisms from nucleation to crystal growth. While the initial precipitation rate of goethite exceeds that of magnetite, continued growth is inhibited by magnetite formation, potentially a result of lower Fe(III) activity. Conversely, the presence of lower initial Fe(II) concentrations followed by higher concentrations promotes goethite accumulation and inhibits magnetite precipitation even when Fe(II) concentrations later increase, thus revealing the importance of both the rate of Fe(II) generation and flow-induced Fe(II) profiles. As such, the operating secondary mineralization pathways following reductive dissolution of ferrihydrite at a given pH are governed principally by flow-regulated Fe(H) concentration, which drives mineral precipitation kinetics and selection of competing mineral pathways. Copyright (C) 2003 Elsevier Ltd. C1 Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Hansel, CM (reprint author), Stanford Univ, Dept Geol & Environm Sci, Braun Hall,Bldg 320,Room 118, Stanford, CA 94305 USA. RI Benner, Shawn/A-2557-2012 OI Benner, Shawn/0000-0003-4024-5777 NR 51 TC 281 Z9 292 U1 13 U2 133 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 AUG PY 2003 VL 67 IS 16 BP 2977 EP 2992 DI 10.1016/S0016-7037(03)00276-X PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 709DK UT WOS:000184609300006 ER PT J AU Spycher, N Pruess, K Ennis-King, J AF Spycher, N Pruess, K Ennis-King, J TI CO2-H2O mixtures in the geological sequestration of CO2. I. Assessment and calculation of mutual solubilities from 12 to 100 degrees C and up to 600 bar SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID CARBON-DIOXIDE-WATER; PHASE-EQUILIBRIA; THERMODYNAMIC PROPERTIES; THEORETICAL PREDICTION; AQUEOUS-ELECTROLYTES; LIQUID-EQUILIBRIUM; HYDRATE FORMATION; HYDROGEN-SULFIDE; H2O-CO2 MIXTURES; HIGH-PRESSURES AB Evaluating the feasibility of CO2 geologic sequestration requires the use of pressure-temperature-composition (P-T-X) data for mixtures of CO2 and H2O at moderate pressures and temperatures (typically below 500 bar and below 100degreesC). For this purpose, published experimental P-T-X data in this temperature and pressure range are reviewed. These data cover the two-phase region where a CO2-rich phase (generally gas) and an H2O-rich liquid coexist and are reported as the mutual solubilities of H2O and CO, in the two coexisting phases. For the most part, mutual solubilities reported from various sources are in good agreement. In this paper, a noniterative procedure is presented to calculate the composition of the compressed CO2 and liquid H2O phases at equilibrium, based on equating chemical potentials and using the Redlich-Kwong equation of state to express departure from ideal behavior. The procedure is an extension of that used by King et al. (1992), covering a broader range of temperatures and experimental data than those authors, and is readily expandable to a nonideal liquid phase. The calculation method and formulation are kept as simple as possible to avoid degrading the performance of numerical models of water-CO2 flows for which they are intended. The method is implemented in a computer routine, and inverse modeling is used to determine, simultaneously, (1) new Redlich-Kwong parameters for the CO2-H2O mixture, and (2) aqueous solubility constants for gaseous and liquid CO2 as a function of temperature. In doing so, mutual solubilities of H2O from 15 to 100degreesC and CO2 from 12 to 110degreesC and up to 600 bar are generally reproduced within a few percent of experimental values. Fugacity coefficients of pure CO2 are reproduced mostly within one percent of published reference data. Copyright (C) 2003 Elsevier Ltd. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. CSIRO Petr, Glen Waverley 3150, Australia. RP Spycher, N (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS 90-1116,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Spycher, Nicolas/E-6899-2010 NR 51 TC 390 Z9 403 U1 8 U2 116 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 AUG PY 2003 VL 67 IS 16 BP 3015 EP 3031 DI 10.1016/S0016-7037(03)00273-4 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 709DK UT WOS:000184609300009 ER PT J AU Owen, LA Finkel, RC Minnich, RA Perez, AE AF Owen, LA Finkel, RC Minnich, RA Perez, AE TI Extreme southwestern margin of late Quaternary glaciation in North America: Timing and controls SO GEOLOGY LA English DT Article DE cosmogenic radionuclide dating; glaciation; San Bernardino Mountains; Last Glacial Maximum; Younger Dryas ID SIERRA-NEVADA; SNOWLINE RECONSTRUCTIONS; YOUNGER DRYAS; CALIFORNIA; GLACIERS; MOUNTAINS; FLUCTUATIONS; ENVIRONMENTS; EVENTS AB Well-preserved latero-frontal moraines in the eastern San Bernardino Mountains of southern California provide evidence for several glacial advances during the late Quaternary and mark the southwesternmost limit of glaciation in the Western Cordillera. Using geomorphology and Be-10 cosmogenic radionuclide dating, a succession of moraines from three glaciated valleys is dated to 18-20 ka (Last Glacial Maximum), 15-16 ka (Heinrich Event 1), 12-13 ka (Younger Dryas Stade), and 5-9 ka (early-middle Holocene). These ages substantiate the view that glaciation throughout the American Cordilleras was synchronous during the late Quaternary. Furthermore, these data show that glacial advances in southern California occur when a significant decrease in summer temperature is coupled with an increase in moisture flux producing high winter snowfall. This allows for perennial snow accumulation that may, under appropriate conditions, persist to form glacial ice. C1 Univ Calif Riverside, Dept Earth Sci, Riverside, CA 92521 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. RP Owen, LA (reprint author), Univ Calif Riverside, Dept Earth Sci, Riverside, CA 92521 USA. NR 30 TC 72 Z9 72 U1 0 U2 7 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD AUG PY 2003 VL 31 IS 8 BP 729 EP 732 DI 10.1130/G19561.1 PG 4 WC Geology SC Geology GA 710AJ UT WOS:000184658400019 ER PT J AU Tenma, N Yasukawa, K Zyvoloski, G AF Tenma, N Yasukawa, K Zyvoloski, G TI Model study of the thermal storage system by FEHM code SO GEOTHERMICS LA English DT Article; Proceedings Paper CT European Geothermal Conference (EGC 2003) CY MAY 25-30, 2003 CL SZEGED, HUNGARY DE thermal storage system; model study; open system; FEHM AB The use of low-temperature geothermal resources is important from the viewpoint of global warming. In order to evaluate various underground projects that use low-temperature geothermal resources, we have estimated the parameters of a typical underground system using the two-well model. By changing the parameters of the system, six different heat extraction scenarios have been studied. One of these six scenarios is recommended because of its small energy loss. (C) 2003 CNR. Published by Elsevier Ltd. All rights reserved. C1 Natl Inst AIST, Tsukuba, Ibaraki 3058569, Japan. Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. RP Tenma, N (reprint author), Natl Inst AIST, 16-1 Onogawa, Tsukuba, Ibaraki 3058569, Japan. NR 2 TC 17 Z9 21 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0375-6505 J9 GEOTHERMICS JI Geothermics PD AUG-DEC PY 2003 VL 32 IS 4-6 BP 603 EP 607 DI 10.1016/S0375-6505(03)00073-7 PG 5 WC Energy & Fuels; Geosciences, Multidisciplinary SC Energy & Fuels; Geology GA 741ED UT WOS:000186445000027 ER PT J AU Simpkins, AA Hamby, DA AF Simpkins, AA Hamby, DA TI Uncertainty in transport factors used to calculate historical dose from I-131 releases at the savannah river site SO HEALTH PHYSICS LA English DT Article DE I-131; dose assessment; computer calculations; ingestion AB During the 1950's, atmospheric release of I-131 was one of the largest contributors to offsite dose at the Savannah River Site. Computer models used to estimate offsite dose involve the use of many parameters with wide ranges of uncertainty. The overall uncertainty in dose can be estimated by propagating the uncertainty of each parameter through the model. A major component of the calculational model can be solved for a given release scenario and condensed into a transport factor, which, when multiplied by the air concentration (or deposition) and the appropriate dose conversion factor, can be used to estimate a specific pathway dose. Uncertainties are estimated for the period of 1955-1961 for all parameters contributing to the I-131 transport factor for each pathway. The overall transport factor including all pathways has ranges characterized by maximum-to-minimum ratios (95% to 5%) of about 40. The parameter shown to have the greatest impact on the transport factor calculation was the fraction of elemental iodine released. C1 Westinghouse Savannah River Co, Aiken, SC 29808 USA. Nucl Engn & Radiat Hlth Phys, Radiat Ctr 130, Corvallis, OR 97331 USA. RP Simpkins, AA (reprint author), Westinghouse Savannah River Co, Savannah River Site, Aiken, SC 29808 USA. EM ali.simpkins@srs.gov FU ODCDC CDC HHS [R32/CCR018377] NR 30 TC 2 Z9 2 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 AUG PY 2003 VL 85 IS 2 BP 194 EP 203 DI 10.1097/00004032-200308000-00008 PG 10 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 702JY UT WOS:000184221800008 PM 12938966 ER PT J AU Cox, M Hoover, MD Grivaud, L Johnson, M Newton, GJ AF Cox, M Hoover, MD Grivaud, L Johnson, M Newton, GJ TI Standards for measuring airborne radioactivity SO HEALTH PHYSICS LA English DT Letter ID AEROSOLS C1 NIOSH, Ctr Dis Control & Prevent, Morgantown, WV 26505 USA. SERAC, DPEA, IRSN, F-91192 Gif Sur Yvette, France. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Cox, M (reprint author), 2501 W Zia Rd 3102, Santa Fe, NM 87505 USA. RI Hoover, Mark/I-4201-2012 OI Hoover, Mark/0000-0002-8726-8127 NR 10 TC 0 Z9 0 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 AUG PY 2003 VL 85 IS 2 BP 236 EP 241 DI 10.1097/00004032-200308000-00016 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 702JY UT WOS:000184221800016 PM 12938973 ER PT J AU Colson, RG Auman, LE AF Colson, RG Auman, LE TI TRU waste absorbent addition project at the Idaho National Engineering and Environmental Laboratory SO HEALTH PHYSICS LA English DT Article DE operational topic; waste management; waste storage; radiation protection AB In order to meet a commitment to ship 3,100 m(3) or transuranic waste to the Waste Isolation Pilot Plant (WIPP), the Idaho National Engineering anti Environmental Laboratory (INEEL) developed a process to add absorbent to TRU waste drums that did not meet WIPP waste acceptance criteria. The development, implementation, and sate completion of this project contributed to the INEEL's success in meeting the commitment three months early. C1 INEEL Radiol Engn, Idaho Falls, ID 83415 USA. RP Colson, RG (reprint author), INEEL Radiol Engn, POB 1625, Idaho Falls, ID 83415 USA. NR 1 TC 0 Z9 0 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 AUG PY 2003 VL 85 IS 2 SU S BP S56 EP S64 DI 10.1097/00004032-200308001-00016 PG 9 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 703WL UT WOS:000184304900013 PM 12865753 ER PT J AU Klemic, GA Bailey, P Elcock, D AF Klemic, GA Bailey, P Elcock, D TI A new tool for analysis of cleanup criteria decisions SO HEALTH PHYSICS LA English DT Article DE operational topic; contamination; environmental; standards; radionuclides AB Radionuclides and other hazardous materials resulting from processes used in nuclear weapons production contaminate soil, groundwater, and buildings around the United States. Cleanup criteria for environmental contaminants are agreed on prior to remediation and underpin the scope and legacy of the cleanup process. Analysis of cleanup criteria call be relevant for future agreements and may also provide insight into a complex decision making process where science and policy issues converge. All Internet accessible database has been established to summarize cleanup criteria and related factors involved in U.S. Department of Energy remediation decisions. This paper reports oil a new user interface for the database that is designed to integrate related information into graphic displays and tables with interactive features that allow exploratory data analysis of cleanup criteria. Analysis of Cs-137 in surface soil is presented as air example. C1 US Dept Homeland Secur, Environm Measurements Lab, New York, NY 10014 USA. Argonne Natl Lab, Environm Assessment Div, Washington, DC 20024 USA. RP Klemic, GA (reprint author), US Dept Homeland Secur, Environm Measurements Lab, 201 Varick St,5th Floor, New York, NY 10014 USA. EM gladys.klemic@eml.doe.gov NR 5 TC 0 Z9 0 U1 1 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 AUG PY 2003 VL 85 IS 2 SU S BP S25 EP S30 DI 10.1097/00004032-200308001-00009 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 703WL UT WOS:000184304900006 PM 12865746 ER PT J AU Ribeiro, RM Layden-Almer, J Powers, KA Layden, TJ Perelson, AS AF Ribeiro, RM Layden-Almer, J Powers, KA Layden, TJ Perelson, AS TI Dynamics of alanine aminotransferase during hepatitis C virus treatment SO HEPATOLOGY LA English DT Article ID CHRONIC LIVER-DISEASE; VIRAL DYNAMICS; INTERFERON-ALFA; UNITED-STATES; ALT LEVELS; IN-VIVO; TRANSAMINASE; THERAPY; INFECTION; RNA AB Studies of the kinetics of hepatitis C virus (HCV) decline during interferon (IFN)-based therapy have led to insights into treatment efficacy. However, the kinetics of serum alanine aminotransferase (ALT), an enzyme used as a surrogate of liver damage, have not been closely monitored, and it is not known if they correlate with those of HCV RNA. Here we describe the associations between ALT and HCV dynamics. We analyzed 35 patients treated daily with 10 mIU IFN-alpha2b with or without ribavarin for 28 days followed by standard IFN/ribavirin therapy. Patients exhibited 4 patterns of ALT change: (1) exponential decay of ALT, (2) transient increase in ALT followed by a decrease to pretreatment or normal levels, (3) increase in ALT to a new level, and (4) no significant change. By simultaneously modeling HCV and ALT dynamics, we successfully fit the observed changes. We found ALT decays with t(1/2) = 12.7 hours. The transient increase in ALT observed in some patients suggested a mild hepatotoxic effect of IFN. However, patients with a smaller initial ALT increase achieved higher rates of viral negativity by week 72 (P = .02). The week-4 ALT decline correlated with the HCV log drop (P = .006) and the efficacy of therapy (P = .025). In conclusion, our results suggest the use of ALT as a surrogate marker for treatment effect in patients with elevated ALT. C1 Los Alamos Natl Lab, Theoret Biol & Biophys Grp, Los Alamos, NM 87545 USA. Univ Illinois, Dept Med, Chicago, IL USA. RP Perelson, AS (reprint author), Los Alamos Natl Lab, Theoret Biol & Biophys Grp, MS K710, Los Alamos, NM 87545 USA. FU NCRR NIH HHS [M01 RR13987, RR06555-12]; NIDDK NIH HHS [DK58320-01] NR 37 TC 34 Z9 37 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0270-9139 J9 HEPATOLOGY JI Hepatology PD AUG PY 2003 VL 38 IS 2 BP 509 EP 517 DI 10.1053/jhep.2003.50344 PG 9 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 707VV UT WOS:000184531300027 PM 12883496 ER PT J AU Zhang, Z Zhu, SJ Hamilton, JH Ramayya, AV Hwang, JK Xu, RQ Jiang, Z Xiao, SD Lee, IY Rasmussen, JO Ma, WC AF Zhang, Z Zhu, SJ Hamilton, JH Ramayya, AV Hwang, JK Xu, RQ Jiang, Z Xiao, SD Lee, IY Rasmussen, JO Ma, WC TI Identification of collective bands in neutron-rich Ru-113 nucleus SO HIGH ENERGY PHYSICS AND NUCLEAR PHYSICS-CHINESE EDITION LA Chinese DT Article DE nuclear structure; collective band; spontaneous fission ID ISOTOPES AB Through measuring high-fold prompt gamma-ray coincidence events following the spontaneous fission of Cf-252 with the Gammasphere detector array, new level scheme in the very neutron-rich odd-A Ru-113 nucleus has been established. An intruder collective band based on 11/2(-) level has been identified with spin up to 31/2 h and excitation energy 3.6 MeV. This band most probably originates from nuh(11/2) intruder orbital. Another collective band probably built on 9/2(-) level is also observed. Some important characteristics of the collective bands have been systematically discussed. C1 Tsinghua Univ, Dept Phys, Beijing 100084, Peoples R China. Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Mississippi State Univ, Dept Phys, Mississippi State, MS 39762 USA. RP Tsinghua Univ, Dept Phys, Beijing 100084, Peoples R China. EM zhushj@mail.tsinghua.edu.cn RI Jiang, Zhuo/E-3110-2010 NR 11 TC 2 Z9 2 U1 0 U2 1 PU SCIENCE PRESS PI BEIJING PA 16 DONGHUANGCHENGGEN NORTH ST, BEIJING 100717, PEOPLES R CHINA SN 0254-3052 J9 HIGH ENERG PHYS NUC JI High Energy Phys. Nucl. Phys.-Chin. Ed. PD AUG PY 2003 VL 27 IS 8 BP 688 EP 691 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 711GG UT WOS:000184730800007 ER PT J AU Kosteski, T Kherani, NP Stradins, P Gaspari, F Shmayda, WT Sidhu, LS Zukotynski, S AF Kosteski, T Kherani, NP Stradins, P Gaspari, F Shmayda, WT Sidhu, LS Zukotynski, S TI Tritiated amorphous silicon betavoltaic devices SO IEE PROCEEDINGS-CIRCUITS DEVICES AND SYSTEMS LA English DT Article ID A-SI-H; METASTABLE DEFECTS; RELAXATION; SATURATION; HYDROGEN; SPECTRA AB The introduction of tritium into hydrogenated amorphous silicon has given rise to a novel material with interesting physical properties and potential applications. Tritium undergoes radioactive decay, transforming into He-3(+) and emitting an electron with average energy 5.7 keV, at a rate equivalent to a half-life of 12.3 years. The decay of tritium results in the creation of electron-hole pairs and in the formation of dangling bonds. Infrared spectroscopy and effusion measurements were used to analyse tritium bonding in the silicon network. Electron spin resonance and photoluminescence of tritiated amorphous silicon were examined as a function of time to study the evolution of dangling bonds. Thermal annealing was used to study metastability of dangling bonds in the material. Electrical characteristics of pin diodes containing tritium in the intrinsic layer were investigated. The application of tritiated-hydrogenated amorphous silicon in betavoltaic devices is presented. C1 Univ Toronto, Dept Elect & Comp Engn, Toronto, ON M5S 3G4, Canada. Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. Univ Waterloo, Waterloo, ON N2L 3G1, Canada. RP Kosteski, T (reprint author), Univ Toronto, Dept Elect & Comp Engn, 10 Kings Coll Rd, Toronto, ON M5S 3G4, Canada. NR 30 TC 26 Z9 27 U1 5 U2 10 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1350-2409 J9 IEE P-CIRC DEV SYST JI IEE Proc.-Circuit Device Syst. PD AUG PY 2003 VL 150 IS 4 BP 274 EP 281 DI 10.1049/ip-cds:20030628 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA 734AT UT WOS:000186033600006 ER PT J AU Magri, R Zunger, A AF Magri, R Zunger, A TI Theory of optical properties of segregated InAs/GaSb superlattices SO IEE PROCEEDINGS-OPTOELECTRONICS LA English DT Article; Proceedings Paper CT 5th International Conference on Mid-Infrared Optoelectronics Materials and Devices CY SEP 08-11, 2002 CL ANNOPOLIS, MARYLAND ID COMMON-ATOM; SEMICONDUCTORS; INTERFACE; LASERS; PSEUDOPOTENTIALS; HETEROSTRUCTURES; PARAMETERS; ENERGY; GROWTH; ALLOYS AB The authors study the effects of interfacial atomic segregation on the electronic and optical properties of InAs/GaSb superlattices. They describe their atomistic empirical pseudo-potential method and test its performance against the available experimental data. They show its ability to predict the band structure dependence on the detailed atomic configuration, and thus to properly account for the effects of interfacial atomic segregation and structural disorder. They also show how their method avoids the approximations underlying the pseudopotential method of Dente and Tilton, which gives different results. The application of the proposed method to the InAs/GaSb superlattices allows the explanation of some observed experimental results, such as: the bandgap difference between (InAs)(8)/(GaSb)(8) superlattices with almost pure InSb-like or GaAs-like interfaces; the large blue shift of the bandgap when the growth temperature of the superlattice increases; and the blue shift of the bandgap of (InAs)8/(GaSb)(n) superlattices with increasing GaSb period n. They present a detailed comparison of their predicted blue shift with that obtained by other theories. C1 Ist Nazl Fis Mat, Modena, Italy. Univ Modena Reggio Emilia, Dipartimento Fis, Modena, Italy. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Magri, R (reprint author), Ist Nazl Fis Mat, Via Campi 213-A, Modena, Italy. RI Zunger, Alex/A-6733-2013; Magri, Rita/O-5267-2016 OI Magri, Rita/0000-0003-2945-0374 NR 30 TC 7 Z9 7 U1 0 U2 8 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 1350-2433 J9 IEE P-OPTOELECTRON JI IEE Proc.-Optoelectron. PD AUG PY 2003 VL 150 IS 4 BP 409 EP 414 DI 10.1049/ip-opt:20030843 PG 6 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA 744KN UT WOS:000186628700029 ER PT J AU Tarman, TD Witzke, EL Pierson, LG Campbell, PL AF Tarman, TD Witzke, EL Pierson, LG Campbell, PL TI Enforced isolation processes and data SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB This paper highlights the problem of run-time execution correctness of high consequence applications in conventional Von Neumann computer architectures. It proposes an approach - trusted objects - in which the application program and data are cryptographically encapsulated in their own environment. The remainder of this paper is organized as follows: after the authors present a description of trusted objects, their creation, and their execution, their potential applications are described. Finally, issues and problems requiring further research are discussed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Tarman, TD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 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 AUG PY 2003 VL 18 IS 8 BP 9 EP 12 DI 10.1109/MAES.2003.1224966 PG 4 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 714AW UT WOS:000184891000004 ER PT J AU Mesnier, M Ganger, GR Riedel, E AF Mesnier, M Ganger, GR Riedel, E TI Object-based storage SO IEEE COMMUNICATIONS MAGAZINE LA English DT Article AB Storage technology has enjoyed considerable growth since the first disk drive was introduced nearly 50 years ago, in part facilitated by the slow and steady evolution of storage interfaces (SCSI and ATA/IDE). The stability of these interfaces has allowed continual advances in both storage devices and applications, without frequent changes to the standards. However, the interface ultimately determines the functionality supported by the devices, and current interfaces are holding system designers back. Storage technology has progressed to the point that a change in the device interface is needed. Object-based storage is an emerging standard designed to address this problem. In this article we describe object-based storage, stressing how it improves data sharing, security, and device intelligence. We also discuss some industry applications of object-based storage and academic research using objects as a foundation for building,even more intelligent storage systems. C1 Carnegie Mellon Univ, Parallel Data Lab, Pittsburgh, PA 15213 USA. Intel Corp, Santa Clara, CA 95051 USA. Seagate Res, Interfaces & Architecture Dept, Pittsburgh, PA USA. Carnegie Mellon Univ, ECE Dept, Pittsburgh, PA 15213 USA. Argonne Natl Lab, NEOS Project, Argonne, IL 60439 USA. RP Mesnier, M (reprint author), Carnegie Mellon Univ, Parallel Data Lab, Pittsburgh, PA 15213 USA. NR 14 TC 95 Z9 117 U1 2 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0163-6804 J9 IEEE COMMUN MAG JI IEEE Commun. Mag. PD AUG PY 2003 VL 41 IS 8 BP 84 EP 90 DI 10.1109/MCOM.2003.1222722 PG 7 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 709RM UT WOS:000184638200010 ER PT J AU Hsu, A Chuang, SL AF Hsu, A Chuang, SL TI Wavelength conversion by dual-pump four-wave mixing in an integrated laser modulator SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE distributed-feedback (DFB) laser; electroabsorption modulator; four-wave mixing (FWM) ID SEMICONDUCTOR OPTICAL AMPLIFIER AB Dual-pump four-wave mixing for wavelength conversion is demonstrated using a distributed-feedback laser integrated with two electroabsorption modulators. The device acts as both the conversion medium and the dual-pump source. For a given input probe signal, output conjugate signal-to-noise ratio values of greater than 10 dB were measured over probe wavelengths ranging from 1557 to 1564 nm for a probe-conjugate detuning of 0.5 nm. C1 Univ Illinois, Dept Elect & Comp Engn, Urbana, IL 61801 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hsu, A (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 5 Z9 5 U1 0 U2 2 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 AUG PY 2003 VL 15 IS 8 BP 1120 EP 1122 DI 10.1109/LPT.2003.815325 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 704YX UT WOS:000184370500034 ER PT J AU Jordan, GB Strait, LD Binkley, JS AF Jordan, GB Strait, LD Binkley, JS TI The dream lab SO IEEE POTENTIALS LA English DT Editorial Material ID ORGANIZATIONS C1 US DOE, Off Sci, Washington, DC 20585 USA. Sandia Natl Labs, Washington, DC USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0278-6648 J9 IEEE POTENTIALS JI IEEE Potentials PD AUG-SEP PY 2003 VL 22 IS 3 BP 8 EP 12 DI 10.1109/MP.2003.1232306 PG 5 GA 716QB UT WOS:000185038900003 ER PT J AU Wirthlin, MJ McMurtrey, B AF Wirthlin, MJ McMurtrey, B TI Web-based IP evaluation and distribution using applets SO IEEE TRANSACTIONS ON COMPUTER-AIDED DESIGN OF INTEGRATED CIRCUITS AND SYSTEMS LA English DT Article; Proceedings Paper CT 39th Design Automation Conference (DAC) CY JUN 10-14, 2002 CL NEW ORLEANS, LA SP IEEE DE applets; intellectual propery; JHDL ID JAVA APPLETS AB This paper introduces an IP evaluation and delivery framework that operates within Java applets. The use of such applets; allows circuit designers to create, evaluate, test, and obtain FPGA circuits directly within a web browser. Based on the JHDL design tool, these applets allow structural viewing, circuit simulation, and netlist generation of application-specific circuits. An important component of this framework is the ability to deliver black-box simulation models as executable Java applets. These applet-based simulation models can be tied to third-party simulation tools using network sockets. Several techniques for interfacing black-box applet models to external simulators are described. C1 Brigham Young Univ, Dept Elect & Comp Engn, Provo, UT 84602 USA. Sandia Natl Labs, Albuquerque, NM 87123 USA. RP Brigham Young Univ, Dept Elect & Comp Engn, Provo, UT 84602 USA. EM wirthlin@ee.byu.edu NR 23 TC 3 Z9 3 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0278-0070 EI 1937-4151 J9 IEEE T COMPUT AID D JI IEEE Trans. Comput-Aided Des. Integr. Circuits Syst. PD AUG PY 2003 VL 22 IS 8 BP 985 EP 994 DI 10.1109/TCAD.2003.814946 PG 10 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 704YY UT WOS:000184370600004 ER PT J AU Aykac, D Hoffman, EA McLennan, G Reinhardt, JM AF Aykac, D Hoffman, EA McLennan, G Reinhardt, JM TI Segmentation and analysis of the human airway tree from three-dimensional X-ray CT images SO IEEE TRANSACTIONS ON MEDICAL IMAGING LA English DT Article DE airway segmentation; pulmonary imaging; volumetric imaging; X-ray CT ID LUNG AB The lungs exchange air with the external environment via the pulmonary airways. Computed tomography (CT) scanning can be used to obtain detailed images of the pulmonary anatomy, including the airways. These images have been used to measure airway geometry, study airway reactivity, and guide surgical interventions. Prior to these applications, airway segmentation can be used to identify the airway lumen in the CT images. Airway tree segmentation can be performed manually by an image analyst, but the complexity of the tree makes manual segmentation tedious and extremely time-consuming. We describe a fully automatic technique for segmenting the airway tree in three-dimensional (3-D) CT images of the thorax. We use grayscale morphological reconstruction to identify candidate airways on CT slices and then reconstruct a connected 3-D airway tree. After segmentation, we estimate airway branchpoints based on connectivity changes in the reconstructed tree. Compared to manual analysis on 3-mm-thick electron-beam CT images, the automatic approach has an overall airway branch detection sensitivity of approximately 73%. C1 Univ Iowa, Dept Biomed Engn, Iowa City, IA 52242 USA. Oak Ridge Natl Lab, Engn Sci & Technol Div, Oak Ridge, TN 37831 USA. Univ Iowa, Dept Radiol, Iowa City, IA 52242 USA. Univ Iowa, Dept Internal Med, Iowa City, IA 52242 USA. RP Reinhardt, JM (reprint author), Univ Iowa, Dept Biomed Engn, Iowa City, IA 52242 USA. FU NHLBI NIH HHS [HL64368-01, HL60158-02] NR 22 TC 118 Z9 121 U1 2 U2 13 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0278-0062 J9 IEEE T MED IMAGING JI IEEE Trans. Med. Imaging PD AUG PY 2003 VL 22 IS 8 BP 940 EP 950 DI 10.1109/TMI.2003.815905 PG 11 WC Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging SC Computer Science; Engineering; Imaging Science & Photographic Technology; Radiology, Nuclear Medicine & Medical Imaging GA 708KY UT WOS:000184567100003 PM 12906248 ER PT J AU Young, JL Sterbentz, JW AF Young, JL Sterbentz, JW TI The circular homogeneous-ferrite microwave cirulator - An asypmtotic Green's function and impedance analysis SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE asymptotic analysis; circulator; ferrite; Green's function ID JUNCTION CIRCULATOR; STRIPLINE; OPERATION; LOSSES AB A detailed analysis of the circular, homogeneous ferrite microwave circulator is provided. Particular emphasis is on the circulator's Green's function and the impact of the asymptotic term within the Green's function on convergence, data quality, and design methodology. The asymptotic term is shown to be logarithmic, which suggests that the Green's function is weakly singular when the source and observation points occupy the same location. With the Green's function properly understood, two techniques-one analytical and one numerical-are then offered to integrate that function in order to obtain Z-parameter data and, subsequently, S-parameter data. Data are provided to show rapid convergence of all parameters of interest. A small coupling angle. approximation is then given for the Z-parameters and, from that approximation, a first-order design equation is obtained that relates the coupling angle to circulator radius. A circulator design example is presented and compared to a design associated with the Wu and Rosenbaum method; the comparison substantiates the small coupling angle approximation and design formula. C1 Univ Idaho, Dept Elect & Comp Engn, Moscow, ID 83844 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Young, JL (reprint author), Univ Idaho, Dept Elect & Comp Engn, Moscow, ID 83844 USA. RI Young, Jeffrey/B-1591-2017 OI Young, Jeffrey/0000-0001-6647-4303 NR 20 TC 4 Z9 4 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD AUG PY 2003 VL 51 IS 8 BP 1939 EP 1945 DI 10.1109/TMTT.2003.815268 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 705BG UT WOS:000184375900006 ER PT J AU Valentine, JD AF Valentine, JD TI A report from the Editor for Nuclear Science Symposium contributions to IEEE Transactions on Nuclear Science SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Editorial Material C1 Lawrence Livermore Natl Lab, Def Sci Engn Div, Livermore, CA 94550 USA. RP Valentine, JD (reprint author), Lawrence Livermore Natl Lab, Def Sci Engn Div, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 750 EP 750 DI 10.1109/TNS.2003.815810 PN 1 PG 1 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000001 ER PT J AU Hollerman, WA Allison, SW Goedeke, SM Boudreaux, P Guidry, R Gates, E AF Hollerman, WA Allison, SW Goedeke, SM Boudreaux, P Guidry, R Gates, E TI Comparison of fluorescence properties for single crystal and polycrystalline YAG : Ce SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE half brightness dose; phosphors; radiation damage; YAG : Ce ID FLUOR MATERIALS AB For more than a century, materials that emit visible light when exposed to ionizing radiation, or "fluors," have been used for a variety of scientific and engineering purposes. The Term "half brightness dose" (N-1/2) was developed as a consistent figure of merit to evaluate the effectiveness of a material to emit fluorescence as a function of radiation exposure. Research indicates that certain properties, such as half brightness dose, fluorescence intensity, and prompt decay time, could depend on crystalline structure. The average 3 MeV proton N-1/2 for a polycrystalline YAG:Ce paint was found to be 1.28 x 10(14) mm(-2), which is consistent with earlier research. The 3 MeV proton N-1/2 for the virgin YAG:Ce crystal was found to be 3.1 times larger than was measured for the polycrystalline paint. Subsequent N-1/2 measurements with the crystal were slightly lower than the virgin data and larger than was obtained from the polycrystalline PPMS paint. C1 Univ Louisiana, Dept Phys, Lafayette, LA 70504 USA. Oak Ridge Natl Lab, Engn Sci & Technol Div, Oak Ridge, TN 37831 USA. RP Hollerman, WA (reprint author), Univ Louisiana, Dept Phys, Lafayette, LA 70504 USA. RI Hollerman, William/F-5943-2011; OI Allison, Stephen/0000-0002-5887-5403 NR 8 TC 30 Z9 30 U1 0 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 754 EP 757 DI 10.1109/TNS.2003.814535 PN 1 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000003 ER PT J AU Engels, R Kemmerling, G Cooper, R Schelten, J AF Engels, R Kemmerling, G Cooper, R Schelten, J TI Detection properties of a neutron counter based on scintillator, wavelength shifter, and photomultiplier SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VA DE detector; neutron; photomultiplier; scintillator; wavelength shifter AB A simple neutron counter based on a scintillator strip, a wavelength shifter rod, and a photomultiplier was constructed in order to compare the properties of such a detector to a commercially available (3)He counter. A calculation of the number of photons per absorbed neutron shows that with the bright (6)Li (158)Gd ((11)BO(3))(3) scintillator, light levels should be sufficient to perform pulse height discrimination. This has been experimentally demonstrated. Furthermore, the performance of this scintillation neutron counter has been measured in time-of-flight experiments where simultaneously the neutron spectra we. re recorded with a (3)He proportional counter. C1 Forschungszentrum Julich, Zent Lab Elektron, D-52425 Julich, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Forschungszentrum Julich, Inst Schicht & Ionentech, D-52425 Julich, Germany. RP Engels, R (reprint author), Forschungszentrum Julich, Zent Lab Elektron, D-52425 Julich, Germany. EM r.engels@fz-juelich.de; g.kemmerling@fz-juelich.de; cooperrg@sns.gov; j.schelten@fz-juelich.de RI Engels, Rutger/A-5984-2010 NR 2 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 758 EP 761 DI 10.1109/TNS.2003.814546 PG 4 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000004 ER PT J AU Yu, B Radeka, V Smith, GC Woody, CL Smirnoff, NN AF Yu, B Radeka, V Smith, GC Woody, CL Smirnoff, NN TI Study of GEM characteristics for application in a microTPC SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE gas electron multiplier; interpolating pad/strip readout; micro pattern gaseous detector; time projection chamber ID GAS ELECTRON MULTIPLIER; AMPLIFICATION; READOUT; CHAMBER; MWPC AB The gas electron multiplier (GEM) may provide a convenient method for obtaining significant electron multiplication over large detector areas. An important potential application of the GEM is in microTPCs. We are conducting a study of a multi-GEM structure with particular emphasis on the following characteristics: gain uniformity/stability, ion feedback, and position readout. In particular, we present the first experimental results of interpolating anode pad readout. Initial results provide encouragement that the GEM application in microTPCs may be realized. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Yale Univ, New Haven, CT 06520 USA. RP Yu, B (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 10 TC 14 Z9 14 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 836 EP 841 DI 10.1109/TNS.2003.814586 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000018 ER PT J AU Rapisarda, SM Wilcer, NG Olsen, JT AF Rapisarda, SM Wilcer, NG Olsen, JT TI Real-time data reorganizer for the D0 central fiber tracker trigger system at Fermilab SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE crosspoint switch; data communication; data handling; data processing; digital systems; field programmable gate arrays (FPGAs); real time systems; scintillation detectors; spreadsheet programs; synchronization; time division multiplexing AB A custom digital data mixer system has been designed to reorganize, in real time, the data produced by the Fermilab DO scintillating Fiber Detector. The data are used for the Level 1 and Level 2 trigger decisions. The, mixer system receives the data from the front-end digitization electronics over 320 low voltage differential signaling (LVDS) links running at 371 MHz. The input data are de-serialized down to 53 MHz by the LVDS receivers, clock/frame re-synchronized and multiplexed in field programmable gate arrays (FPGAs). The data are then re-serialized at 371 MHz by LVDS transmitters over 320 LVDS output links and sent to the electronics responsible for Level 1 and Level 2 trigger decisions. The data mixer system processes 311 gigabits per second of data with an input to output delay of 200 ns. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Rapisarda, SM (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 9 TC 4 Z9 4 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 878 EP 884 DI 10.1109/TNS.2003.815163 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000025 ER PT J AU De Geronimo, G O'Connor, P Beuttenmuller, RH Li, Z Kuczewski, AJ Siddons, DP AF De Geronimo, G O'Connor, P Beuttenmuller, RH Li, Z Kuczewski, AJ Siddons, DP TI Development of a high-rate high-resolution detector for EXAFS experiments SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE EXAFS; readout ASIC; SI pixel sensor ID READOUT ASICS AB A new detector for EXAFS experiments is being developed. It is based on a multi-element Si sensor and dedicated readout application specific integrated circuit (ASIC). The sensor is composed of 384 pixels, each having 1 mm 2 area, arranged in four quadrants of 12 x 8 elements and it is wire-bonded to 32-channel ASICs. Each channel implements low-noise preamplification with self-adaptive continuous reset, high-order shaper, bandgap referenced baseline stabilizer, one threshold comparator, and two digital-analog converter (DAC) adjustable window comparators, each followed by a 24-bit counter. Fabricated in 0.35 mum CMOS, the ASIC dissipates about 8 mW per channel. First measurements show at room temperature a resolution of 14 e(-) rms without the detector and 40 e(-s) rms (340 eV) with the detector connected and biased. Cooling to -35 C a full width at half maximum (FWHM) of 205 eV (167 eV from electronics) was measured at the Mn-Kalpha line. A resolution of about 300 eV was measured for rates approaching 100 kc/s per channel, corresponding to an overall rate in excess of 10 Mc/s/cm(2). Channel-to channel threshold dispersion after DAC adjustment 2.5 was e(-) root mean square. C1 Brookhaven Natl Lab, Div Instrumentat, Upton, NY 11973 USA. Brookhaven Natl Lab, Natl Synchrotoron Light Source, Upton, NY 11973 USA. RP De Geronimo, G (reprint author), Brookhaven Natl Lab, Div Instrumentat, Upton, NY 11973 USA. NR 7 TC 34 Z9 34 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 885 EP 891 DI 10.1109/TNS.2003.814540 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000026 ER PT J AU O'Connor, P De Geronimo, G Kandasamy, A AF O'Connor, P De Geronimo, G Kandasamy, A TI Amplitude and time measurement ASIC with analog derandomization: First results SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE analog memory; derandomizer; peak detector; spectroscopy ID SILICON STRIP DETECTORS; LOW-NOISE; READOUT; SYSTEM AB We describe a new amplitude specific integrated circuit (ASIC) for accurate and efficient processing of high-rate pulse signals from highly segmented detectors. In contrast to conventional approaches, this circuit affords a dramatic reduction in data volume through the use of analog techniques (precision peak detectors and time-to-amplitude converters) together with fast arbitration and sequencing logic to concentrate the data before digitization. In operation the circuit functions like a data-driven analog first-in, first-out (FIFO) memory between the preamplifiers and the analog-to-digital converter (ADC). Peak amplitudes of pulses arriving at any one of the 32 inputs are sampled, stored, and queued for readout and digitization through a single output port. Hit timing, pulse risetime, and channel address are also available at the output. Prototype chips have been fabricated in 0.35 micron CMOS and tested; First results indicate proper functionality for pulses down to 30 ns peaking time and random input rates up to 1.6 MHz on a single channel. Amplitude accuracy of the peak detect and hold circuit is 0.3% (absolute). TAC accuracy is within 0.3% of full scale. Power consumption is less than 2 mW/channel at the maximum counting rate. Compared with conventional techniques such as track-and-hold and analog memory; this new ASIC will enable efficient pulse height measurement at 20 to 300 times higher rates. C1 Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP O'Connor, P (reprint author), Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. NR 12 TC 14 Z9 14 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 892 EP 897 DI 10.1109/TNS.2003.814541 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000027 ER PT J AU Weng, M Mandelli, E Moses, WW Derenzo, SE AF Weng, M Mandelli, E Moses, WW Derenzo, SE TI A high-speed low-noise CMOS 16-channel charge-sensitive preamplifier ASIC for APD-based PET detectors SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE ASIC; avalanche photodiode; positron emission tomography(PET); preamplifier ID HIGH-RESOLUTION PET; AVALANCHE PHOTODIODES; WIDE-BAND; ARRAYS; MODULE; LSO AB A high-speed low-noise 16-channel amplifier integrated circuit (IC) has been fabricated in a 0.5 mum CMOS process. It is a prototype for use with a PET detector that uses a 4 x 4 avalanche photodiode (APD) array having 3 pF of capacitance and 75 nA of leakage current per pixel. The preamplifier, must have a fast rise time (a few ns) in order to generate an accurate timing signal, low noise in order to accurately measure the energy of the incident gamma radiation, and high density in order to read out. 2-D arrays of small (2 mm) pixels. A single channel consists of a charge-sensitive preamplifier followed by a pad-driving buffer. The preamplifier is reset by an NMOS transistor in the triode region which is controlled by an externally supplied, current. The IC has 16 different gain settings ranging from 2.1 mV/fC to 10.7 mV/fC. The gain is determined by four switched capacitors in the feedback loop. The switch state is set using a 64-bit shift register. A preamplifier 10%-90% rise time as low as 2.7 ns, with no external input load and 3.6 ns with a load of 5.8 pF was achieved. For the maximum gain setting and purely capacitive (5.8 pF) input load, the amplifier had 400 electrons root mean square (rms) noise at a peaking time of 0.7 mus. When loaded with an APD pixel (similar to3 PF capacitance, 125 nA leakage current), a noise minimum of 1550 electrons rms at a peaking time of 0.1 mus Is achieved. The IC is powered by a +3.3 V supply drawing 60 mA. C1 Micrel Semicond, San Jose, CA 95131 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Weng, M (reprint author), Micrel Semicond, San Jose, CA 95131 USA. NR 11 TC 13 Z9 13 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 898 EP 902 DI 10.1109/TNS.2003.814565 PN 1 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000028 ER PT J AU Macri, JR Wintenberg, AL Widholm, M Jagadish, U Ledoux, J McConnell, ML Frank, SS Cutlip, H AF Macri, JR Wintenberg, AL Widholm, M Jagadish, U Ledoux, J McConnell, ML Frank, SS Cutlip, H TI Readout of scintillating plastic fibers with an APD array and prototype ASIC SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE Application-specific integrated circuit (ASIC); avalanche photodiode (APD); complimentary metal-oxide-semiconductor; low power; scintillating fiber AB We report on the development of custom front-end electronics for use with avalanche photodiode (APD) arrays as part of a NASA, technology study for the readout of scintillating plastic fibers. APD arrays featuring. 64 1 mm square pixels are used. We demonstrate that a pixel of these APD arrays coupled to relatively thin (0.25 mm). and short (15 cm) scintillating. plastic fibers can be used to detect and measure the tracks of even minimum ionizing particles. An application-specific integrated circuit (ASIC) implementation of the electronics is required to produce a detector sufficiently compact for practical use in a space flight experiment featuring many thousands of channels. This paper briefly describes the detector concept and performance and presents the design and performance of a four-channel prototype ASIC fabricated using the 0.35 mu Taiwan Semiconductor Manu facturing Company (TSMC) process. C1 Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Raytheon Santa Barbara Remote Sensing, Goleta, CA 93117 USA. RP Macri, JR (reprint author), Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA. NR 5 TC 2 Z9 2 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 928 EP 935 DI 10.1109/TNS.2003.815108 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000033 ER PT J AU Ericson, MN Britton, CL Rochelle, JM Blalock, BJ Binkley, DM Wintenberg, AL Williamson, BD AF Ericson, MN Britton, CL Rochelle, JM Blalock, BJ Binkley, DM Wintenberg, AL Williamson, BD TI Flicker noise behavior of MOSFETs fabricated in 0.5 mu m fully depleted (FD) silicon-on-sapphire (SOS) CMOS in weak, moderate, and strong inversion SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE CMOSFETs; flicker noise; inversion coefficient; noise measurement; silicon on insulator technology ID LHC EXPERIMENTS; RADIATION; CIRCUITS; DETECTOR; TECHNOLOGIES; DESIGN AB This paper presents a summary of the measured noise behavior of CMOS MOSFET's fabricated in the Peregrine 0.5 mum fully depleted (FD) silicon-on-sapphire (SOS) process. SOS, CMOS technology provides an alternative to standard bulk CMOS processes for high-density detector front-end electronics due to its inherent radiation tolerance. In this paper, the flicker noise behavior of SOS devices will be presented and discussed with reference to device inversion coefficient (IC). The concept of inversion coefficient will be introduced and the results of SOS device noise measurements in weak, moderate, and strong inversion will be presented and compared for devices with gate lengths of 0.5 mum to 4 mum. Details of the noise measurement system will be provided including specifics of the measurement approach and custom circuits used for device biasing. This work will provide a thorough presentation of measured SOS device flicker noise as a function of inversion coefficient. In addition, strategies for device biasing and sizing to obtain optimum flicker noise performance will be presented encouraging more widespread use of SOS integrated circuits in high-density detector applications. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Concorde Microsyst Inc, Knoxville, TN 37932 USA. Univ Tennessee, Knoxville, TN 37966 USA. Univ N Carolina, Charlotte, NC 28223 USA. RP Ericson, MN (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 16 TC 7 Z9 7 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 963 EP 968 DI 10.1109/TNS.2003.815146 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000038 ER PT J AU Matis, HS Bieser, F Kleinfelder, S Rai, G Retiere, F Ritter, HG Singh, K Wurzel, SE Wieman, H Yamamoto, E AF Matis, HS Bieser, F Kleinfelder, S Rai, G Retiere, F Ritter, HG Singh, K Wurzel, SE Wieman, H Yamamoto, E TI Charged particle detection using a CMOS active pixel sensor SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE active pixel sensor; CMOS integrated circuit; heavy ions; particle tracking; proton radiation effects; semiconductor device radiation effects; semiconductor radiation detectors; vertex detectors; X-ray image sensor ID VERTEX DETECTOR; TRACKING AB Active pixel sensor (APS) is a promising technology for next-generation vertex detectors. This paper discusses the design and testing of two generations of APS chips. Both are arrays of 128 by 128 pixels, each 20 by 20 mum. Each array is divided into subarrays in which different sensor structures (4 in the first version and 16 in the second) and/or readout circuits are employed. Measurements of several of these structures, under Fe-55 exposure are reported. The sensors have also been irradiated by 55 MeV protons to test for radiation damage. The radiation increases the noise and reduces the signal. The noise can be explained by shot noise from the increased leakage current, and the reduction in signal is due to charge being trapped in the epi layer. Nevertheless, the radiation effect is small for the expected exposures at RHIC and RHIC II. Finally, we describe our conception for mechanically supporting a thin silicon wafer in an actual detector. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Irvine, Dept Elect & Comp Engn, Irvine, CA 96297 USA. RP Matis, HS (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 15 TC 49 Z9 48 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 1020 EP 1025 DI 10.1109/TNS.2003.815159 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000048 ER PT J AU Mitani, T Nakamura, H Uno, S Takahashi, T Nakazawa, K Watanabe, S Tajima, H Nomachi, M Fukazawa, Y Kubo, S Kuroda, Y Onishi, M Ohno, R AF Mitani, T Nakamura, H Uno, S Takahashi, T Nakazawa, K Watanabe, S Tajima, H Nomachi, M Fukazawa, Y Kubo, S Kuroda, Y Onishi, M Ohno, R TI Large area gamma-ray imaging detector based on high-resolution CdTe diode SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VA DE CdTe; gamma camera; gamma-ray ID SPECTROSCOPY; PERFORMANCE; READOUT AB We are developing a-large array detector composed of 1024 individual CdTe diodes. Each detector has the dimensions of 1.2 nun x 5.0 mm and a thickness of 1.2 nun. An edge-on geometry is used for the injection of gamma-rays, to obtain a cross-section thickness of 5 mm. With this geometry, the distance between the two electrodes can be kept small, and we can therefore apply the high electric field which is necessary to achieve a high energy resolution (by reducing the low energy tail) and also to sustain the long-term stability of the CdTe diode. Signals from each detector element are fed into newly developed low noise ASICs. We use 32 chips for the readout of 1024 elements. In this paper, we report the basic characteristics of the individual detectors and the overall performance of the gamma-camera. Design of the readout electronics system is also described. C1 Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Univ Tokyo, Dept Phys, Tokyo 1130033, Japan. Osaka Univ, Nucl Studies Lab, Toyonaka, Osaka 5600043, Japan. Hiroshima Univ, Dept Phys, Hiroshima 7398526, Japan. Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. Clear Pulse Ltd, Tokyo 1430024, Japan. Mitsubishi Heavy Ind Co Ltd, Nagoya Guidance & Propuls Syst Works, Aichi 4858561, Japan. Daiichi Syst Engn Co Ltd, Aichi 4858561, Japan. RP Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. EM mitani@astro.isas.ac.jp NR 11 TC 14 Z9 14 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9499 EI 1558-1578 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 1048 EP 1052 DI 10.1109/TNS.2003.815320 PN 1 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000054 ER PT J AU Kim, JG Dardin, SM Kadel, RW Kadyk, JA Jackson, KH Peskov, V Wenzel, WA Joo, KS AF Kim, JG Dardin, SM Kadel, RW Kadyk, JA Jackson, KH Peskov, V Wenzel, WA Joo, KS TI Further studies of electron avalanche gain in liquid argon SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE electron avalanche; liquid argon; liquid xenon ID XENON; EMISSION; FIELD AB Previously, we showed how small admixtures of xenon (Xe) stabilize electron avalanches in liquid Argon (LAr). In the present work, we have measured the positive charge carrier mobility in LAr with small admixtures of Xe to be 6.4 x 10(-3) cm(2) /Vs, in approximate agreement with the mobility measured in pure LAr and consistent with holes as charge carriers. We have measured the concentration of Xe actually dissolved in the liquid and compared the results with expectations based on the amount of Xe gas added to the LAr. We also have tested LAr doped with krypton to investigate the mechanism of avalanche stabilization. C1 Lawrence Berkeley Natl Lab, Div Phys, Berkeley, CA 94720 USA. Myongli Univ, Dept Phys, Young In 449728, South Korea. Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Royal Inst Technol, Stockholm, Sweden. RP Kim, JG (reprint author), Lawrence Berkeley Natl Lab, Div Phys, Berkeley, CA 94720 USA. NR 11 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 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 1073 EP 1077 DI 10.1109/TNS.2003.815139 PN 1 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000058 ER PT J AU Zwaska, RM Hall, J Kopp, SE Proga, M Erwin, AR Ping, HC Velissaris, C Harris, DA Naples, D McDonald, J Northacker, D Diwan, M Viren, B AF Zwaska, RM Hall, J Kopp, SE Proga, M Erwin, AR Ping, HC Velissaris, C Harris, DA Naples, D McDonald, J Northacker, D Diwan, M Viren, B TI Beam tests of ionization chambers for the NuMI neutrino beam SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE ionization chambers; ionizing radiation; multiplication; neutrinos; particle beam measurements; space charge AB We have conducted tests at the Fermilab Booster of ionization chambers to be used as monitors of the NuMI neutrino beamline. The chambers were exposed to proton fluxes of up to 10(12) particles/cm(2)/1.56 mus. We studied space charge effects which can reduce signal collection from the chambers at large charged particle beam intensities. C1 Univ Texas, Dept Phys, Austin, TX 78712 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Pittsburgh, Dept Phys, Pittsburgh, PA 15260 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Zwaska, RM (reprint author), Univ Texas, Dept Phys, Austin, TX 78712 USA. NR 19 TC 8 Z9 8 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 1129 EP 1135 DI 10.1109/TNS.2003.815148 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000066 ER PT J AU Coluccia, MR Appel, JA Chiodini, G Christian, DC Cihangir, S Kwan, SW Sellberg, G AF Coluccia, MR Appel, JA Chiodini, G Christian, DC Cihangir, S Kwan, SW Sellberg, G TI Electrical characterization of irradiated prototype silicon pixel sensors for BTeV SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE BTeV; radiation effects; silicon pixel detector ID READOUT CHIP; RADIATION; DETECTOR; DAMAGE; ATLAS AB The pixel detector in the BTeV experiment at the Tevatron (Fermilab) provides high-resolution tracking and vertex identification. For this task, the hybrid pixel detector has to work in a very harsh radiation environment with 1014 minimum ionizing particles/cm(2)/year. Radiation hardness of prototype n(+)/n/p(+) silicon pixel sensors has been investigated. We present electrical characterization curves for irradiated prototype n(+)/n/p(+) sensors, intended for use in the BTeV experiment. We tested pixel sensors from various vendors and with two pixel isolation techniques: p-stop and p-spray. Results are based on irradiation with 200 MeV protons up to 6 x 10(14) protons/cm(2). C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Coluccia, MR (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 19 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 1136 EP 1141 DI 10.1109/TNS.2003.815315 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000067 ER PT J AU Cardona, J Peggs, S Kewisch, J AF Cardona, J Peggs, S Kewisch, J TI Optical design of the rapid cycling medical synchrotron SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE FODO; optics; protons; synchrotron AB The optical design of the rapid cycling medical synchrotron (RCMS) is based on the strong focusing principle. Several advantages arise from this choice of design, including smaller beam sizes and more optimization possibilities. In this paper, a detailed description of the optical design of all beam lines of the facility is presented with the methods that have been used to optimize such beam lines. In particular, we describe a method to match beam lines optimally in one step using as input parameters the beta functions at the matching point. This method eliminates the need of doing repeated simulations varying several parameters of the matching elements until the match is finally achieved. Comparisons between old designs and the most recent design are presented making special emphasis on cost savings between them. Comparisons with other accelerators and technologies is also presented. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. SUNY Stony Brook, Stony Brook, NY 11790 USA. RP Cardona, J (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 10 TC 4 Z9 4 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 1147 EP 1152 DI 10.1009/TNS.2003.815103 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000069 ER PT J AU Dombeck, TW AF Dombeck, TW TI A possible water calorimeter based on radiation-induced conductivity SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE accelerator; calorimetry; dosimetry; ionization; radiation detectors; safety ID ABSORPTION SPECTRA; IRRADIATED WATER; ELECTRON-BEAMS; DOSIMETRY; CALIBRATION; EQUIVALENT; TRACKS AB A calorimeter is proposed that measures the delivered dosage of radiation by the induced electrical conductivity in water through the production of long-lived ions. The device is being developed for use in providing real-time measurements of beam losses in particle accelerators. It promises to be a simple, reliable, and accurate device with a linear response,from a fraction of a gray up to a megagray, with potential application in industry and medical clinics. A theoretical model of the physical processes that produce the long-lived ions based on delta rays is presented in this paper and compared with the existing data. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Dombeck, TW (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 25 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 1153 EP 1160 DI 10.1109/TNS.2003.815104 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000070 ER PT J AU Hahn, S Elphic, R Murphy, T Hodgson, M Byrd, R Longmire, J Lawrence, D Barraclough, B Fuller, K Prettyman, T Meier, M Dors, E Funsten, H Belian, R Patrick, D Moore, T Sweet, M Burczyk, L Williford, R Clanton, C AF Hahn, S Elphic, R Murphy, T Hodgson, M Byrd, R Longmire, J Lawrence, D Barraclough, B Fuller, K Prettyman, T Meier, M Dors, E Funsten, H Belian, R Patrick, D Moore, T Sweet, M Burczyk, L Williford, R Clanton, C TI A validation payload for space and atmospheric nuclear event detection SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE gamma-ray detectors; nuclear explosions; nuclear measurements; particle measurements AB We describe an experimental flight validation payload for detecting atmospheric and space nuclear events with a planned launch date in 2004. The five detector subsystems in the payload employ 27 sensors including Si, CdZnTe, gas proportional counter tubes, photomultiplier tubes, channel electron multipliers, and photodiodes. Detection of events is based on simultaneous measurements of gamma rays, neutrons, and charged particles with wide dynamic ranges of deposited energy and count rates. The sensors and electronics are housed in one package with approximate mass and power consumption of 27 kg and 50 watts, respectively. The instrument uses sophisticated on-board digital signal processing and multilayer triggering algorithms to detect and assess the validity of small signals in a large background radiation environment. This paper presents system configuration and preliminary test data from the first of the two units in development. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hahn, S (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Murphy, Thomas/F-3101-2014; Funsten, Herbert/A-5702-2015; Lawrence, David/E-7463-2015 OI Murphy, Thomas/0000-0002-6137-9873; Prettyman, Thomas/0000-0003-0072-2831; Funsten, Herbert/0000-0002-6817-1039; Lawrence, David/0000-0002-7696-6667 NR 5 TC 4 Z9 4 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 1175 EP 1181 DI 10.1109/TNS.2003.815125 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000074 ER PT J AU Prettyman, TH Feldman, WC Ameduri, FP Barraclough, BL Cascio, EW Fuller, KR Funsten, HO Lawrence, DJ McKinney, GW Russell, CT Soldner, SA Storms, SA Szeles, C Tokar, RL AF Prettyman, TH Feldman, WC Ameduri, FP Barraclough, BL Cascio, EW Fuller, KR Funsten, HO Lawrence, DJ McKinney, GW Russell, CT Soldner, SA Storms, SA Szeles, C Tokar, RL TI Gamma-ray and neutron spectrometer for the dawn mission to 1 Ceres and 4 Vesta SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT Nuclear Science Symposium (NSS)/Symposium on Nuclear Power Systems (SNPS) CY NOV 10-16, 2002 CL NORFOLK, VIRGINIA DE gamma-ray spectroscopy; planets; neutron spectroscopy; semiconductor device radiation effects ID RADIATION-DAMAGE; LUNAR PROSPECTOR; MARS ODYSSEY; DETECTORS; CDZNTE; PERFORMANCE; SPECTRA; SURFACE AB We present the design of the gamma-ray and neutron spectrometer (GR/NS) for Dawn, which is a NASA Discovery-class mission to explore two of the largest main-belt asteroids, 1 Ceres and 4 Vesta, who se accretion is believed to have been interrupted by the early formation of Jupiter. Dawn will determine the composition and structure of these protoplanetary bodies, providing context for a large number of primitive meteorites in our sample collection and a better understanding of processes occurring shortly after the onset of condensation of the solar nebula. The Dawn GR/NS design draws on experience from the successful Lunar Prospector and Mars Odyssey missions to enable accurate mapping of the surface composition and stratigraphy of major elements, radioactive elements, and hydrogen at both asteroids. Here, we describe the overall design of the GR/NS and compare the expected performance of the neutron spectrometer subsystem to the neutron spectrometer on Mars Odyssey. We also describe radiation damage studies carried out on CdZnTe detectors, which will be components of the primary gamma-ray spectrometer on Dawn. We conclude that provisions for annealing at moderate temperatures (40degreesC to 60degreesC) must be made to ensure that the spectrometer will function optimally over the nine-year mission. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Massachusetts Gen Hosp, NE Proton Therapy Ctr, Boston, MA 02114 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA. eV Prod, Saxonburg, PA 16056 USA. RP Prettyman, TH (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Funsten, Herbert/A-5702-2015; Lawrence, David/E-7463-2015; OI Funsten, Herbert/0000-0002-6817-1039; Lawrence, David/0000-0002-7696-6667; Prettyman, Thomas/0000-0003-0072-2831; Russell, Christopher/0000-0003-1639-8298 NR 26 TC 28 Z9 28 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD AUG PY 2003 VL 50 IS 4 BP 1190 EP 1197 DI 10.1109/TNS.2003.815156 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 712GE UT WOS:000184789000076 ER PT J AU Kim, D Economou, DJ Woodworth, JR Miller, PA Shul, RJ Aragon, BP Hamilton, TW Willison, CG AF Kim, D Economou, DJ Woodworth, JR Miller, PA Shul, RJ Aragon, BP Hamilton, TW Willison, CG TI Plasma molding over surface topography: Simulation and measurement of ion fluxes, energies and angular distributions over trenches in RF high density plasmas SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE ion angular distribution; ion energy distribution (IED); ion flow in trenches; Monte Carlo (MC) simulation; plasma molding; two-dimensional (2-D) plasma sheath ID RADIO-FREQUENCY DISCHARGES; CORRECTED TRANSPORT; PROFILE EVOLUTION; REFERENCE CELL; BIASED WAFERS; SHEATH; DYNAMICS; MODEL; SCATTERING; ELECTRODES AB A two-dimensional (2-D) fluid/Monte Carlo (MC) simulation model was developed to study plasma "molding" over a trench. The radio frequency sheath potential evolution and ion density and flux profiles over-the surface were predicted with a self-consistent fluid simulation. The trajectories of ions and energetic neutrals (resulting by ion neutralization on surfaces or charge exchange collisions in the gas phase) were then followed with a MC simulation.. For sheath thickness L-sh comparable to the trench width D, ions were, strongly deflected toward the trench sidewall, and the ion flux along the trench surface contour was highly nonuniform. Irrespective of the trench depth, the normalized spatially-average ion flux at the trench mouth showed a minimum at L-sh/D similar to 1.0. The normalized spatially-average ion flux at the trench bottom decreased with increasing trench depth or aspect ratio) As the trench sidewall was approached, the energy spread DeltaE of the ion energy distributions (IEDs) at the trench bottom decreased for a thin sheath, but increased for a thick sheath. At the trench bottom, the neutral flux was comparable to the ion flux over the entire range of. sheath thickness studied. Simulation results were in good agreement with experimental data on ion flux, IEDs, and ion angular distributions at the trench bottom. C1 Univ Houston, Dept Chem Engn, Plasma Proc Lab, Houston, TX 77204 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. L & M Technol, Albuquerque, NM 87109 USA. RP Univ Houston, Dept Chem Engn, Plasma Proc Lab, Houston, TX 77204 USA. EM economou@uh.edu NR 43 TC 17 Z9 18 U1 1 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0093-3813 EI 1939-9375 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD AUG PY 2003 VL 31 IS 4 BP 691 EP 702 DI 10.1109/TPS.2003.815248 PN 1 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 713AW UT WOS:000184833400025 ER PT J AU Apte, SV Mahesh, K Moin, P Oefelein, JC AF Apte, SV Mahesh, K Moin, P Oefelein, JC TI Large-eddy simulation of swirling particle-laden flows in a coaxial-jet combustor SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Article DE particle-laden flows; LES; unstructured grids; swirling flows ID TURBULENT FLOWS; SCHEMES; GRIDS AB Large-eddy simulation (LES) of particle-laden, swirling flow in a coaxial-jet combustor is performed. A mixture of air and lightly loaded, spherical, glass-particles with a prescribed size-distribution enters the primary jet, while a swirling stream of air flows through the annulus. The incompressible, spatially filtered Navier-Stokes equations are solved on unstructured grids to compute the turbulent gas-phase. A Lagrangian formulation and an efficient particle-tracking scheme on unstructured meshes is developed to compute the dispersed phase. The particles are treated as point sources and influence the gas phase only through momentum-exchange terms. The particle-dispersion characteristics are examined in detail; in particular, the dependence of particle trajectories and residence times upon particle sizes is emphasized. The mean and turbulent quantities for the gas and particle phases are compared to experimental data and good agreement is obtained. The LES results are significantly more accurate than the Reynolds-averaged Navier-Stokes equation (RANS) predictions of the same problem. Insight into the two-phase swirling flows is obtained through the residence-times and particle velocity-diameter correlations. (C) 2003 Elsevier Ltd. All rights reserved. C1 Stanford Univ, Dept Mech Engn, Stanford, CA 94305 USA. Univ Minnesota, Minneapolis, MN 55455 USA. Stanford Univ, Ctr Turbulence Res, Stanford, CA 94305 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Apte, SV (reprint author), Stanford Univ, Dept Mech Engn, Bldg 500,ME-FPC,488 Escondido Mall, Stanford, CA 94305 USA. NR 23 TC 132 Z9 136 U1 1 U2 28 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD AUG PY 2003 VL 29 IS 8 BP 1311 EP 1331 DI 10.1016/S0301-9322(03)00104-6 PG 21 WC Mechanics SC Mechanics GA 710HR UT WOS:000184675200007 ER PT J AU Graham, RL Choi, SE Daniel, DJ Desai, NN Minnich, RG Rasmussen, CE Risinger, LD Sukalski, MW AF Graham, RL Choi, SE Daniel, DJ Desai, NN Minnich, RG Rasmussen, CE Risinger, LD Sukalski, MW TI A network-failure-tolerant message-passing system for terascale clusters SO INTERNATIONAL JOURNAL OF PARALLEL PROGRAMMING LA English DT Article AB The Los Alamos Message Passing Interface (LA-MPI) is an end-to-end network-failure-tolerant message-passing system designed for terascale clusters. LA-MPI is a standard-compliant implementation of MPI designed to tolerate network-related failures including I/O bus errors, network card errors, and wire-transmission errors. This paper details the distinguishing features of LA-MPI, including support for concurrent use of multiple types of network interface, and reliable message transmission utilizing multiple network paths and routes between a given source and destination. In addition, performance measurements on production-grade platforms are presented. C1 Los Alamos Natl Lab, Adv Comp Lab, Los Alamos, NM 87545 USA. RP Graham, RL (reprint author), Los Alamos Natl Lab, Adv Comp Lab, MS-B287, Los Alamos, NM 87545 USA. NR 16 TC 13 Z9 13 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0885-7458 J9 INT J PARALLEL PROG JI Int. J. Parallel Program. PD AUG PY 2003 VL 31 IS 4 BP 285 EP 303 DI 10.1023/A:1024504726988 PG 19 WC Computer Science, Theory & Methods SC Computer Science GA 696UJ UT WOS:000183905700002 ER PT J AU Rubin, MB Lomov, I AF Rubin, MB Lomov, I TI A thermodynamically consistent large deformation elastic-viscoplastic model with directional tensile failure SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article DE directional; porosity; tensile failure; thermomechanical; viscoplastic ID PLASTICITY THEORY; POROUS MATERIALS; 2ND LAW; GROWTH; METALS; MEDIA AB The main objective of this paper is to develop a continuum model for directional tensile failure that can simulate weakening and void formation due to tensile failure. Directionality in the model allows simulation of weakening to tension applied in one direction, without weakening to subsequent tension applied in perpendicular directions. The model is developed within the context of a properly invariant non-linear thermomechanical theory. Specifically, it is shown how the model can be combined with general constitutive equations for porous compaction and dilation, as well as viscoplasticity. The thermoelastic response is hyperelastic, with the stress being determined by derivatives of the Helmholtz free energy, and the material is considered to be elastically isotropic. In particular, it is assumed that the rate of inelasticity due to tensile failure is coaxial with the tensor measure of elastic deformation (and hence stress). This causes the rate of dissipation to take a particularly simple form which can be shown to satisfy the second law of thermodynamics. A numerical procedure for integrating these evolution equations is proposed and a number of examples are considered to explore the response of the model to different loading histories. (C) 2003 Elsevier Ltd. All rights reserved. C1 Technion Israel Inst Technol, Fac Mech Engn, IL-32000 Haifa, Israel. Lawrence Livermore Natl Lab, Geophys & Global Secur Div, Livermore, CA 94550 USA. RP Rubin, MB (reprint author), Technion Israel Inst Technol, Fac Mech Engn, IL-32000 Haifa, Israel. NR 39 TC 7 Z9 7 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD AUG PY 2003 VL 40 IS 17 BP 4299 EP 4318 DI 10.1016/S0020-7683(03)00242-7 PG 20 WC Mechanics SC Mechanics GA 700RP UT WOS:000184125200001 ER PT J AU Sabbaj, S Bansal, A Ritter, GD Perkins, C Edwards, BH Gough, E Tang, JM Szinger, JJ Korber, B Wilson, CM Kaslow, RA Mulligan, MJ Goepfert, PA AF Sabbaj, S Bansal, A Ritter, GD Perkins, C Edwards, BH Gough, E Tang, JM Szinger, JJ Korber, B Wilson, CM Kaslow, RA Mulligan, MJ Goepfert, PA TI Cross-reactive CD8(+) T cell epitopes identified in US adolescent minorities SO JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES LA English DT Article DE CTL epitopes; HIV vaccine; class I restriction; CTL vaccines; CD8 T cell responses ID HUMAN-IMMUNODEFICIENCY-VIRUS; ACTIVE ANTIRETROVIRAL THERAPY; ACUTE HIV-1 INFECTION; TYPE-1 SUBTYPE-C; LYMPHOCYTE-RESPONSES; VIRAL LOAD; IMMUNE-RESPONSES; RHESUS-MONKEYS; CTL RESPONSES; HLA-A AB Vaccines designed to bring forth CD8(+) T cell responses in different racial and ethnic groups will require inclusion of T cell epitopes presented by various MHC class I molecules. This study was designed to identify new CD8(+) T cell epitopes in HIV-infected African American and Hispanic youth as well as to determine the frequency of responses to both novel and previously described HIV-1 epitopes in a cohort of racially and ethnically diverse individuals. We found 8 MHC class I-restricted CD8(+) T cell epitopes that had not been previously described, another 8 epitopes that were restricted by class I alleles not previously associated with these epitopes, and 8 additional epitopes that have been described previously. In a larger cohort, we demonstrated that 11 (69%) of these 16 newly described immunogens were recognized by individuals of different race or ethnicity. Most HIV-1-specific CD8(+) T cell epitopes identified were either novel or restricted by alternative MHC class I alleles. Frequent recognition of several of these CTL epitopes in persons of diverse racial backgrounds bodes well for the development of a broadly reactive HIV-1 vaccine. C1 Univ Alabama, Dept Med, Div Infect Dis, Birmingham, AL 35294 USA. Univ Alabama, Dept Microbiol, Birmingham, AL 35294 USA. Univ Alabama, Dept Epidemiol, Birmingham, AL 35294 USA. Univ Alabama, Dept Pediat, Birmingham, AL 35294 USA. Los Alamos Natl Lab, Los Alamos, NM USA. RP Sabbaj, S (reprint author), Univ Alabama, Dept Med, Div Infect Dis, 908 20th St S,CCB 362, Birmingham, AL 35294 USA. OI Tang, Jianming/0000-0003-0137-7486; Sabbaj, Steffanie/0000-0003-4052-6819 FU NIAID NIH HHS [AI 41951, AI 49126]; NICHD NIH HHS [U01 HD32824] NR 74 TC 27 Z9 29 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1525-4135 J9 JAIDS-J ACQ IMM DEF JI JAIDS PD AUG 1 PY 2003 VL 33 IS 4 BP 426 EP 438 PG 13 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA 703LA UT WOS:000184279800003 PM 12869831 ER PT J AU Yoshida, M Hasegawa, J Kwan, JW Oguri, Y Nakajima, M Horioka, K Ogawa, M AF Yoshida, M Hasegawa, J Kwan, JW Oguri, Y Nakajima, M Horioka, K Ogawa, M TI Grid-controlled extraction of low-charged ions from a laser ion source SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article DE laser ion source; grid-control; KrF excimer laser; heavy ion fusion ID INDUCTION ACCELERATORS; FUSION; BEAMS; CERN AB We developed a grid-controlled laser ion source using a KrF excimer laser and investigated the effects of grid-controlled extraction on beam current waveform and beam quality. By using grid-controlled extraction in the over-dense regime, the beam current waveform was found to be stabilized. The beam current increased in proportion to V-3/2, where V is the extraction voltage, which proves that the grid control worked properly and that the ion beam was extracted in a one-dimensional space-charge-limited mode. Beam quality measurement using a pepper-pot imaging method revealed that the beam optics was strongly disturbed by the grid potential in the source-limit regime. Conversely, in the over-dense regime there were no deleterious effects of the grid bias on the beam patterns. This result indicated that the virtual anode in the gap acted as a kind of momentum filter and improved the beam quality. C1 Tokyo Inst Technol, Nucl Reactors Res Lab, Meguro Ku, Tokyo 1528550, Japan. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Tokyo Inst Technol, Dept Energy Sci, Midori Ku, Yokohama, Kanagawa 2268502, Japan. RP Yoshida, M (reprint author), Tokyo Inst Technol, Nucl Reactors Res Lab, Meguro Ku, 2-12-1 Ookayama, Tokyo 1528550, Japan. RI Horioka, Kazuhiko/B-9844-2015 OI Horioka, Kazuhiko/0000-0002-4524-0775 NR 11 TC 7 Z9 7 U1 0 U2 0 PU INST PURE APPLIED PHYSICS PI TOKYO PA TOYOKAIJI BLDG NO. 12, 6-9-6 SHINBASHI, MINATO-KU, TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PD AUG PY 2003 VL 42 IS 8 BP 5367 EP 5371 DI 10.1143/JJAP.42.5367 PG 5 WC Physics, Applied SC Physics GA 723FY UT WOS:000185422900098 ER PT J AU Rosen, J Anders, A Hultman, L Schneider, JM AF Rosen, J Anders, A Hultman, L Schneider, JM TI Temporal development of the composition of Zr and Cr cathodic arc plasma streams in a N-2 environment SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ION ENERGY-DISTRIBUTIONS; VACUUM ARCS; MAGNETIC-FIELD; GAS; SPOTS AB We describe the temporal development of the plasma composition in a pulsed plasma stream generated by cathodic arc. Cathodes of Zr and Cr were operated at various nitrogen pressures. The time-resolved plasma composition for the cathode materials was analyzed with time-of-flight charge-to-mass spectrometry, and was found to be a strong function of the nitrogen pressure. Large plasma composition gradients were detected within the first 60 mus of the pulse, the nitrogen ion concentration increasing with increasing pressure. The results are explained by the formation and erosion of a compound layer formed at the cathode surface in the presence of a reactive gas. The average charge state was also found to be affected by the reactive gas pressure as well as by the time after ignition. The charge states were highest in the beginning of the pulse at low nitrogen pressure, decreasing to a steady-state value at higher pressure. These results are of importance for reactive plasma processing and for controlling the evolution of thin film composition and microstructure. (C) 2003 American Institute of Physics. C1 Linkoping Univ, Dept Phys, SE-58183 Linkoping, Sweden. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Rhein Westfal TH Aachen, D-52056 Aachen, Germany. RP Linkoping Univ, Dept Phys, SE-58183 Linkoping, Sweden. EM johro@ifm.liu.se RI Schneider, Jochen/A-4701-2012; Rosen, Johanna/M-9284-2014; Anders, Andre/B-8580-2009 OI Anders, Andre/0000-0002-5313-6505 NR 28 TC 16 Z9 16 U1 1 U2 3 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 AUG 1 PY 2003 VL 94 IS 3 BP 1414 EP 1419 DI 10.1063/1.1591079 PG 6 WC Physics, Applied SC Physics GA 705ND UT WOS:000184400400020 ER PT J AU Aubertine, DB Ozguven, N McIntyre, PC Brennan, S AF Aubertine, DB Ozguven, N McIntyre, PC Brennan, S TI Analysis of x-ray diffraction as a probe of interdiffusion in Si/SiGe heterostructures SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SELF-DIFFUSION; ALLOYS; GE; SUPERLATTICES; LAYERS; MULTILAYERS; RELAXATION; STABILITY; MOBILITY; STRAIN AB We investigate numerical simulations that utilize a nonlinear interdiffusion solver and dynamical x-ray diffraction calculations to predict the local composition evolution in low Ge concentration Si/SiGe superlattices and their diffraction patterns during annealing. Superlattice satellite peak decay rates are compared with experimentally measured values and simulated diffraction patterns are matched directly to data with good success. The simulations are used to test the sensitivity of x-ray diffraction to various uncertainties commonly encountered when measuring interdiffusion at Si/SiGe interfaces. It is found that the most serious errors result from variations in the Ge content across the surface of the wafer. For example, the resolution limit of most experimental techniques used to measure Ge concentration in a SiGe film is +/-1 at. %, for a film with 11% mean Ge concentration annealed for 5 h at 870degreesC, this level of error will cause the observed interdiffusivity values to deviate by -25% or +50%. The simulations are further used to show that for Si/SiGe interdiffusion, superlattice diffraction produces valid measurements when applied to 004 superlattice satellite peaks and square wave composition modulations even though it is only exactly applicable to satellite peaks about 000 reflections and to sinusoidal composition modulations. Finally, we show that proper interpretation of x-ray scattering data to extract Si/SiGe interdiffusivity values must account for the strong dependence of the interdiffusivity on Ge concentration. (C) 2003 American Institute of Physics. C1 Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. RP Aubertine, DB (reprint author), Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. NR 23 TC 22 Z9 22 U1 1 U2 6 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 AUG 1 PY 2003 VL 94 IS 3 BP 1557 EP 1564 DI 10.1063/1.1589600 PG 8 WC Physics, Applied SC Physics GA 705ND UT WOS:000184400400042 ER PT J AU Vandersall, KS Thadhani, NN AF Vandersall, KS Thadhani, NN TI Time-resolved measurements of the shock-compression response of Mo+2Si elemental powder mixtures SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INDUCED CHEMICAL-REACTIONS; PRESSURE; SILICIDES; SI AB The shock-compression response of Mo+2Si elemental powder mixtures was investigated using instrumented experiments in the velocity range of 500 m/s to 1 km/s. The experiments employed polyvinyl difluoride stress gauges placed at the front and rear surfaces of the powder mixtures to determine the crush strength, densification history, and shock-induced reaction initiation characteristics. Experiments performed on similar to58% dense Mo+2Si powder mixtures at input stresses less than 4 GPa showed characteristics of powder densification and dispersed propagated wave stress profiles with rise time > similar to40 ns. At input stress between 4 and 6 GPa, the powder mixtures showed a shock-compression response following the Hugoniot of the solid-density mixture. In the stress regime of 6-7 GPa, shock-induced melting of silicon was observed, which appears to inhibit a shock-induced chemical reaction on the time scale of the time-resolved measurements. The results of the present work on Mo-Si, taken in conjunction with prior work on the Nb-Si and Ti-Si systems, illustrate that premature melting of silicon and its capillary flow can limit the deformation and mixing between reactants, thereby inhibiting the initiation of "shock-induced" chemical reactions. (C) 2003 American Institute of Physics. C1 Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Thadhani, NN (reprint author), Georgia Inst Technol, Sch Mat Sci & Engn, 771 Ferst Dr, Atlanta, GA 30332 USA. NR 37 TC 24 Z9 24 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD AUG 1 PY 2003 VL 94 IS 3 BP 1575 EP 1583 DI 10.1063/1.1586968 PG 9 WC Physics, Applied SC Physics GA 705ND UT WOS:000184400400044 ER PT J AU Gfroerer, TH Priestley, LP Fairley, MF Wanlass, MW AF Gfroerer, TH Priestley, LP Fairley, MF Wanlass, MW TI Temperature dependence of nonradiative recombination in low-band gap InxGa1-xAs/InAsyP1-y double heterostructures grown on InP substrates SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID AUGER RECOMBINATION; INGAAS; TRANSITIONS AB We have used photoexcitation-dependent radiative efficiency measurements to investigate the rates of defect-related, radiative, and Auger recombination in lattice-matched InxGa1-xAs/InAsyP1-y double heterostructures on InP substrates. Temperature dependence is used to discern the underlying mechanisms responsible for the nonradiative recombination processes. We find that defect-related recombination decreases with an increase in the temperature when the epistructure is lattice matched to the substrate (x = 0.53). In contrast, when the epistructure is lattice mismatched to the substrate, defect-related recombination increases slowly with the temperature. The difference between the lattice-matched and mismatched cases is related to fundamental changes in the defect-related density of states function. The temperature dependence in the lattice-mismatched structures is attributed to two competing effects: wider carrier diffusion, which augments the capture rate, and thermally activated escape, which reduces the occupation of shallow traps. The band gap and temperature dependence of the Auger rate demonstrate that the conduction to heavy hole band/splitoff to heavy hole band mechanism generally dominates Auger recombination in undoped low-band gap InxGa1-xAs. With this interpretation, our results give a spin-orbit valence split-off band effective mass of m(so) = (0.12 +/- 0.02) m(0). (C) 2003 American Institute of Physics. C1 Davidson Coll, Dept Phys, Davidson, NC 28035 USA. Spelman Coll, Atlanta, GA 30314 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Gfroerer, TH (reprint author), Davidson Coll, Dept Phys, Davidson, NC 28035 USA. NR 25 TC 26 Z9 28 U1 1 U2 6 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 AUG 1 PY 2003 VL 94 IS 3 BP 1738 EP 1743 DI 10.1063/1.1586468 PG 6 WC Physics, Applied SC Physics GA 705ND UT WOS:000184400400064 ER PT J AU Thorat, SD Phillips, PJ Semenov, V Gakh, A AF Thorat, SD Phillips, PJ Semenov, V Gakh, A TI Physical properties of aliphatic polycarbonates made from CO2 and epoxides SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE aliphatic polycarbonates; physical properties; glass-transition temperature; thermal degradation; epoxides AB A homologous series of aliphatic polycarbonates with different side-chain lengths was synthesized by ring-opening polymerization of terminal epoxides with CO2 using zinc adipionate as catalyst [patented process of Empower Materials (formerly PAC Polymers Inc.)]. Additionally, a polycarbonate was made having a cyclohexane unit in its backbone, together with a terpolymer having both cyclohexane and propylene units. After characterization of thermal properties the aliphatic polycarbonates were found to be completely amorphous. Polycarbonates derived from long-chain epoxides showed a glass-transition temperature (T,,) below room temperature, whereas polycarbonates derived from cyclohexene oxide showed a T-g of 105degreesC, the highest yet reported for this class of polymers. The initial decomposition temperature of the polymers in air and nitrogen atmospheres was found to be less than 300degreesC. The mechanical properties and the dynamic mechanical relaxation behavior of the polymers were also reported. The effect of the chemical structure on the physical properties of aliphatic polycarbonates was discussed. (C) 2003 Wiley Periodicals. C1 Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. ND Zelinskii Inst Organ Chem, Moscow 117913, Russia. US DOE, Lockheed Martin Energy Syst, Washington, DC USA. RP Phillips, PJ (reprint author), Univ Tennessee, Dept Mat Sci & Engn, Dougherty Engn Bldg, Knoxville, TN 37996 USA. NR 11 TC 52 Z9 59 U1 2 U2 26 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD AUG 1 PY 2003 VL 89 IS 5 BP 1163 EP 1176 DI 10.1002/app.12355 PG 14 WC Polymer Science SC Polymer Science GA 687BJ UT WOS:000183355700001 ER PT J AU Kim, J Ryba, ER Bai, JM AF Kim, J Ryba, ER Bai, JM TI Effect of the polyurethane crystalline interphase formed at an Al surface on water-vapor absorption SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE polyurethanes; interfaces; spherulites ID STRENGTH; JOINTS AB Water-vapor absorption of polyurethane/Al bonds was studied, and the weight gain of samples after water-vapor exposure was measured to examine the effect of the polyurethane crystalline interphase formed at the Al surface on water-vapor absorption. Water-vapor absorption was found to be independent of the crosslink density of the polyurethanes. Instead, it was found that the microstructural characteristics of the spherulitic interphase, a mixture of crystallites and amorphous material formed on the Al surface, strongly affects water-vapor absorption: As the area fraction and the size of spherulites for the films increases, the amount of absorbed water vapor initially increases rapidly and then remained constant. The water vapor absorbed and condensed at spherulite boundaries consisting of voids and defects was created due to volume contraction during polymer crystallization. (C) 2003 Wiley Periodicals, Inc. C1 Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Ryba, ER (reprint author), Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. RI Bai, Jianming/O-5005-2015 NR 9 TC 0 Z9 0 U1 0 U2 1 PU JOHN WILEY & SONS INC PI HOBOKEN PA 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD AUG 1 PY 2003 VL 89 IS 5 BP 1417 EP 1422 DI 10.1002/app.12264 PG 6 WC Polymer Science SC Polymer Science GA 687BJ UT WOS:000183355700035 ER PT J AU Hussain, NK Yamabhai, M Bhakar, AL Metzler, M Ferguson, SSG Hayden, MR McPherson, PS Kay, BK AF Hussain, NK Yamabhai, M Bhakar, AL Metzler, M Ferguson, SSG Hayden, MR McPherson, PS Kay, BK TI A role for epsin N-terminal homology/AP180 N-terminal homology (ENTH/ANTH) domains in tubulin binding SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID CLATHRIN-MEDIATED ENDOCYTOSIS; ENTH-DOMAIN; DEPENDENT DEPHOSPHORYLATION; INTERACTING PROTEIN; NEURITE OUTGROWTH; RAT HEPATOCYTES; COATED VESICLES; NERVE-TERMINALS; GROWTH; ACTIN AB The epsin N-terminal homology (ENTH) domain is a protein module of similar to150 amino acids found at the N terminus of a variety of proteins identified in yeast, plants, nematode, frog, and mammals. ENTH domains comprise multiple alpha-helices folded upon each other to form a compact globular structure that has been implicated in interactions with lipids and proteins. In characterizing this evolutionarily conserved domain, we isolated and identified tubulin as an ENTH domain-binding partner. The interaction, which is direct and has a dissociation constant of similar to1 muM, was observed with ENTH domains of proteins present in various species. Tubulin is co-immunoprecipitated from rat brain extracts with the ENTH domain-containing proteins, epsins 1 and 2, and punctate epsin staining is observed along the microtubule cytoskeleton of dissociated cortical neurons. Consistent with a role in microtubule processes, the over-expression of epsin ENTH domain in PC12 cells stimulates neurite outgrowth. These data demonstrate an evolutionarily conserved property of ENTH domains to interact with tubulin and microtubules. C1 McGill Univ, Dept Neurol & Neurosurg, Montreal Neurol Inst, Montreal, PQ H3A 2B4, Canada. Suranaree Univ Technol, Sch Biotechnol, Inst Agr Technol, Nakhon Ratchasima 30000, Thailand. Univ British Columbia, Ctr Mol Med & Therapeut, Ctr Med Genet, Vancouver, BC V5Z 4H4, Canada. Robarts Res Inst, Cell Biol Res Grp, London, ON N6A 5K8, Canada. Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. RP McPherson, PS (reprint author), McGill Univ, Dept Neurol & Neurosurg, Montreal Neurol Inst, 3801 Univ Ave, Montreal, PQ H3A 2B4, Canada. RI Hayden, Michael/D-8581-2011 OI Hayden, Michael/0000-0001-5159-1419 NR 62 TC 20 Z9 21 U1 0 U2 0 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD AUG 1 PY 2003 VL 278 IS 31 BP 28823 EP 28830 DI 10.1074/jbc.M300995200 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 705XC UT WOS:000184421100060 PM 12750376 ER PT J AU Fisher, RD Wang, B Alam, SL Higginson, DS Robinson, H Sundquist, WI Hill, CP AF Fisher, RD Wang, B Alam, SL Higginson, DS Robinson, H Sundquist, WI Hill, CP TI Structure and ubiquitin binding of the ubiquitin-interacting motif SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID RECEPTOR-MEDIATED ENDOCYTOSIS; PROTEASE SUBUNIT; MEMBRANE-FUSION; EARLY ENDOSOMES; UBA DOMAINS; PROTEINS; SURFACE; EPS15; CLATHRIN; PATHWAY AB Ubiquitylation is used to target proteins into a large number of different biological processes including proteasomal degradation, endocytosis, virus budding, and vacuolar protein sorting (Vps). Ubiquitylated proteins are typically recognized using one of several different conserved ubiquitin binding modules. Here, we report the crystal structure and ubiquitin binding properties of one such module, the ubiquitin-interacting motif (UIM). We found that UIM peptides from several proteins involved in endocytosis and vacuolar protein sorting including Hrs, Vps27p, Stam1, and Eps15 bound specifically, but with modest affinity (K-d = 0.1 - 1 mM), to free ubiquitin. Full affinity ubiquitin binding required the presence of conserved acidic patches at the N and C terminus of the UIM, as well as highly conserved central alanine and serine residues. NMR chemical shift perturbation mapping experiments demonstrated that all of these UIM peptides bind to the I44 surface of ubiquitin. The 1.45 Angstrom resolution crystal structure of the second yeast Vps27p UIM (Vps27p-2) revealed that the ubiquitin-interacting motif forms an amphipathic helix. Although Vps27p-2 is monomeric in solution, the motif unexpectedly crystallized as an antiparallel four-helix bundle, and the potential biological implications of UIM oligomerization are therefore discussed. C1 Univ Utah, Dept Biochem, Sch Med, Salt Lake City, UT 84132 USA. Brookhaven Natl Lab, Dept Biol 463, Upton, NY 11973 USA. RP Sundquist, WI (reprint author), Univ Utah, Dept Biochem, Sch Med, Salt Lake City, UT 84132 USA. NR 67 TC 137 Z9 138 U1 1 U2 11 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD AUG 1 PY 2003 VL 278 IS 31 BP 28976 EP 28984 DI 10.1074/jbc.M302596200 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 705XC UT WOS:000184421100078 PM 12750381 ER PT J AU Babikov, D Kendrick, BK Walker, RB Pack, RT Fleurat-Lesard, P Schinke, R AF Babikov, D Kendrick, BK Walker, RB Pack, RT Fleurat-Lesard, P Schinke, R TI Formation of ozone: Metastable states and anomalous isotope effect SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POTENTIAL-ENERGY SURFACE; RATE COEFFICIENTS; HEAVY OZONE; DISSOCIATION THRESHOLD; TEMPERATURE-DEPENDENCE; INTRAMOLECULAR THEORY; O-16-O-18 MIXTURES; FORMATION RATES; LOW-PRESSURES; FRACTIONATION AB A clear explanation for an anomalous isotope effect in ozone formation is given in terms of the energy transfer mechanism, where the metastable states of ozone are formed first, and then stabilized by collisions with other atoms. Unusual nonstatistical properties of metastable states spectra discovered earlier [J. Chem. Phys. 118, 6298 (2003)] are incorporated into the kinetics model, where different metastable states are treated as different species, and the stabilization step is treated approximately. The population of the ozone metastable states builds up and decays through three possible O-2+O channels. When different isotopes of oxygen are involved the three channels become open at different energies because of the differences in the quantum zero-point-energies (DeltaZPE) of the different O-2 molecules. The spectrum of metastable states is anomalously dense below the DeltaZPE threshold and these states are accessible only from the lower entrance channel. Also, these low-lying metastable states are stabilized very efficiently (by collisions with third body) because they are energetically close to the bound O-3 states. Such processes significantly enhance the formation rates of ozone isotopologues through the lower channels over the formation rates through the upper channels. Numerical results obtained for J=0 give isotope effects in the right direction and of the right order of magnitude. Consideration of J>0 should improve the comparison with experiment. (C) 2003 American Institute of Physics. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Max Planck Inst Stromungsforsch, D-37073 Gottingen, Germany. RP Babikov, D (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Fleurat-Lessard, Paul/C-9080-2009 OI Fleurat-Lessard, Paul/0000-0003-3114-2522 NR 42 TC 69 Z9 70 U1 1 U2 11 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 AUG 1 PY 2003 VL 119 IS 5 BP 2577 EP 2589 DI 10.1063/1.1587113 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 702UE UT WOS:000184242100011 ER PT J AU Asthagiri, D Pratt, LR Ashbaugh, HS AF Asthagiri, D Pratt, LR Ashbaugh, HS TI Absolute hydration free energies of ions, ion-water clusters, and quasichemical theory SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; STANDARD FREE-ENERGY; COMPUTER-SIMULATIONS; CHLORIDE-ION; LIQUID WATER; SOLVATION; POTENTIALS; SURFACE; EQUILIBRIUM; PHOTODETACHMENT AB Experimental studies of ion-water clusters have provided insights into the microscopic aspects of hydration phenomena. One common view is that extending those experimental studies to larger cluster sizes would give the single-ion absolute hydration free energies not obtainable by classical thermodynamic methods. This issue is reanalyzed in the context of recent computations and molecular theories of ion hydration, particularly considering the hydration of H+, Li+, Na+, and HO- ions, and thence the hydration of neutral ion pairs. The hydration free energies of neutral pairs computed here are in good agreement with experimental results, whereas the calculated absolute hydration free energies and the excess chemical potentials deviate consistently from some recently tabulated hydration free energies based on ion-water cluster data. We show how the single-ion absolute hydration free energies are not separated from the potential of the phase in recent analyses of ion-water cluster data, even in the limit of large cluster sizes. We conclude that naive calculations of ion-water clusters ought to agree with results obtained from experimental studies of ion-water clusters because both values include the contribution, somewhat extraneous to the local environment of the ion, from the potential of the phase. (C) 2003 American Institute of Physics. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Asthagiri, D (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Asthagiri, Dilipkumar/A-3383-2010; Pratt, Lawrence/H-7955-2012; Ashbaugh, Henry/C-9767-2011; Asthagiri, Dilipkumar/P-9450-2016 OI Pratt, Lawrence/0000-0003-2351-7451; Asthagiri, Dilipkumar/0000-0001-5869-0807 NR 62 TC 134 Z9 134 U1 4 U2 43 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 AUG 1 PY 2003 VL 119 IS 5 BP 2702 EP 2708 DI 10.1063/1.1587122 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 702UE UT WOS:000184242100025 ER PT J AU Steele, WV Chirico, RD Cowell, AB Nguyen, A Knipmeyer, SE AF Steele, WV Chirico, RD Cowell, AB Nguyen, A Knipmeyer, SE TI Possible precursors and products of deep hydrodesulfurization of gasoline and distillate fuels. Part 2. The thermodynamic properties of 2,3-dihydrobenzo[b]thiophene SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article DE enthalpy of combustion; heat capacity; vapor pressure; density; thermodynamic functions ID THERMOCHEMICAL BOND ENERGIES; 3RD VIRIAL-COEFFICIENT; TEMPERATURES 250 K; VAPOR-PRESSURE; XYLENE ISOMERIZATION; RECOMMENDED VALUES; HEAT-CAPACITIES; KINETICS; EQUILIBRIA; DENSITIES AB Measurements leading to the calculation of the standard thermodynamic properties for gaseous 2,3-dihydrobenzo[b]thiophene (Chemical Abstracts registry number [4565-32-6]) are reported. Experimental methods include combustion calorimetry, adiabatic heat-capacity calorimetry, vibrating-tube densitometry, comparative ebulliometry, inclined-piston gauge manometry, and differential-scanning calorimetry (d.s.c.). Critical properties are estimated for 2,3-dihydobenzo[b]thiophene. Standard molar entropies, standard molar enthalpies, and standard molar Gibbs free energies of formation are derived at selected temperatures between T = 298.15 K and T = 680 K. Crown Copyright (C) 2003 Published by Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Phys Propert Res Facil, Nucl Sci & Technol Div, Oak Ridge, TN 37831 USA. Natl Inst Stand & Technol, TRC, Phys & Chem Propert Div, Boulder, CO 80305 USA. BDM Petr Technol, Bartlesville Thermodynam Grp, Bartlesville, OK 74005 USA. RP Steele, WV (reprint author), Oak Ridge Natl Lab, Phys Propert Res Facil, Nucl Sci & Technol Div, POB 2008,Mail Stop 6273, Oak Ridge, TN 37831 USA. NR 81 TC 8 Z9 8 U1 0 U2 1 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0021-9614 J9 J CHEM THERMODYN JI J. Chem. Thermodyn. PD AUG PY 2003 VL 35 IS 8 BP 1253 EP 1276 DI 10.1016/S0021-9614(03)00063-6 PG 24 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA 714VB UT WOS:000184933200004 ER PT J AU Wise, BM Gallagher, NB Grate, JW AF Wise, BM Gallagher, NB Grate, JW TI Analysis of combined mass- and volume-transducing sensor arrays SO JOURNAL OF CHEMOMETRICS LA English DT Article; Proceedings Paper CT 3rd International Chemomtrics Research Meeting (ICRM2002) CY MAY 26-30, 2002 CL VELDHOVEN, NETHERLANDS DE sensor; acoustic wave; array; classical least squares ID WAVE VAPOR SENSORS; SORBENT COATINGS; RESPONSES; CLASSIFICATION; SOLUBILITY AB In prior work it was shown that both mass- and volume-transducing sensor arrays with polymer coatings can be modeled with a classical least squares (CLS)-type formulation. Given a response vector, this method allows one to solve simultaneously for the vapor descriptors and concentration, even for previously unseen analytes. It has also been shown that inverse least squares (ILS) models can be used in this system to estimate vapor descriptors. A more challenging task is to extract vapor descriptors from sensor arrays which respond to both mass and volume changes simultaneously. This problem is important because surface acoustic wave (SAW) sensors, and probably other types of sensors such as flexural plate wave (FPW) sensors, respond via both mass and volume mechanisms. In this work we show how a closed-form solution can be obtained to a slightly simplified mass- and volume-sensitive system. This solution can be further refined with direct optimization using the full modeling equations. Simulations are performed to evaluate the accuracy of the approximate and refined solutions. This is compared with the accuracy of the known descriptors. Copyright (C) 2003 John Wiley Sons, Ltd. C1 Eigenvector Res Inc, Manson, WA 98831 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Wise, BM (reprint author), Eigenvector Res Inc, 830 Wapato Lake Rd, Manson, WA 98831 USA. NR 14 TC 7 Z9 7 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0886-9383 J9 J CHEMOMETR JI J. Chemometr. PD AUG-SEP PY 2003 VL 17 IS 8-9 BP 463 EP 469 DI 10.1002/cem.792 PG 7 WC Automation & Control Systems; Chemistry, Analytical; Computer Science, Artificial Intelligence; Instruments & Instrumentation; Mathematics, Interdisciplinary Applications; Statistics & Probability SC Automation & Control Systems; Chemistry; Computer Science; Instruments & Instrumentation; Mathematics GA 736GL UT WOS:000186163000005 ER PT J AU Gritti, F Guiochon, G AF Gritti, F Guiochon, G TI Band splitting in overloaded isocratic elution chromatography I. The experimental evidence SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE band splitting; band profile; fraction collection; phenol ID PREPARATIVE LIQUID-CHROMATOGRAPHY; PROFILES; REPRODUCIBILITY; REPEATABILITY; ISOTHERMS AB A series of samples of increasing volume (from 0.001 to 4.0 cm(3)), containing the same constant concentration (40 g/l) of two simple compounds, ethylbenzoate and 4-tert.-butylphenol were injected on a Kromasil-C-18 column with methanol-water (62:38, v/v) as the mobile phase. Complex band profiles were observed when the volume of the sample became large enough and strong band interference took place. The analysis of the fractions collected during the elution of the mixed band demonstrates that, for samples larger than 2 cm(3), the band of 4-tert.-butylphenol is split into two separate bands, one eluted before and the other eluted after the band of ethylbenzoate. Such a phenomenon has never been observed yet in RPLC, under isocratic elution conditions. (C) 2003 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 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 17 TC 11 Z9 11 U1 0 U2 0 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 AUG 1 PY 2003 VL 1008 IS 1 BP 13 EP 21 DI 10.1016/S0021-9673(03)00972-5 PG 9 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 707TJ UT WOS:000184525700002 PM 12943247 ER PT J AU Gritti, F Guiochon, G AF Gritti, F Guiochon, G TI Band splitting in overloaded isocratic elution chromatography II. New competitive adsorption isotherms SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE band splitting; adsorption equilibrium; frontal analysis; adsorption energy distribution; ideal adsorbed solution theory; adsorption isotherms; mathematical modeling; toluene; ethylbenzene ID PHASE LIQUID-CHROMATOGRAPHY; MASS-TRANSFER KINETICS; REPRODUCIBILITY; THERMODYNAMICS; REPEATABILITY; PROFILES; SYSTEM; COLUMN AB The equations of two new binary competitive isotherms models are derived. The first of these models assumes that the isotherms of the two pure, single compounds have distinct monolayer capacities. Its derivation is based on kinetic arguments. The ideal adsorbed solution (IAS) framework was applied to derive the second model that is a thermodynamically consistent competitive isotherm. This second model predicts the competitive adsorption isotherm behavior of a mixture of two compounds that have single-component adsorption behavior following a BET and/or a Langmuir isotherms. Both models apply well to the binary adsorption of ethylbenzoate and 4-tert.-butylphenol on a Kromasil-C-18 column (with methanol-water, 62:38, v/v, as the mobile phase). The best single-solute adsorption isotherms of these two compounds are the liquid-solid extended multilayer BET and the Langmuir isotherms, respectively. The kinetic and thermodynamic new competitive models were compared, regarding the accuracy of their prediction of the elution band profiles of mixtures of these two compounds. A better agreement between experimental and calculated profiles was observed with the kinetic model. The IAS model failed because the behavior of the ethylbenzoate/4-tert.-butylphenol adsorbed phase mixture is probably non-ideal. The most striking result is the qualitative prediction by these models of the peak splitting of 4-tert.-butylphenol during its elution in presence of ethylbenzoate. (C) 2003 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, 552 Buehler Hall, Knoxville, TN 37996 USA. NR 31 TC 21 Z9 21 U1 0 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 AUG 1 PY 2003 VL 1008 IS 1 BP 23 EP 41 DI 10.1016/S0021-9673(03)00970-1 PG 19 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 707TJ UT WOS:000184525700003 PM 12943248 ER PT J AU Palmedo, H Manka-Waluch, A Albers, P Schmidt-Wolf, IGH Reinhardt, M Ezziddin, S Joe, A Roedel, R Fimmers, R Knapp, FF Guhlke, S Biersack, HJ AF Palmedo, H Manka-Waluch, A Albers, P Schmidt-Wolf, IGH Reinhardt, M Ezziddin, S Joe, A Roedel, R Fimmers, R Knapp, FF Guhlke, S Biersack, HJ TI Repeated bone-targeted therapy for hormone-refractory prostate carcinoma: Randomized phase II trial with the new, high-energy radiopharmaceutical rhenium-188 hydroxyethylidenediphosphonate SO JOURNAL OF CLINICAL ONCOLOGY LA English DT Article ID DOUBLE-BLIND CROSSOVER; RADIONUCLIDE THERAPY; OSSEOUS METASTASES; CLINICAL-TRIAL; SR-89 THERAPY; SKELETAL METASTASES; PAIN PALLIATION; CANCER PATIENTS; EFFICACY; DISEASE AB Purpose: We investigated the effect of repeated bone-targeted therapy with rhenium-188 hydroxyethylidene-diphosphonate (HEDP) in patients with progressive, hormone-resistant prostate carcinoma and bone pain. The aim of this study was to determine the pain palliation and the antitumor effect of rhenium-188 HEDP treatments. Patients and Methods: Sixty-four patients were randomly assigned to one of two groups for radionuclide therapy with rhenium-188 HEDP; patients of group A received a single injection, patients of group B received two injections (interval, 8 weeks). After therapy, patients were followed-up by assessment of pain palliation and clinical outcome until death. Results: In both groups, toxicity was low, with moderate thrombopenia and leukopenia (maximum common toxicity criteria grade of 2). The effectiveness of rhenium-188 HEDP for pain palliation was better in the repeated treatment group (group B), with a response rate and time of response of 92% and 5.66 months, respectively (P = .006 and P = .001). In group B, 11 (39%) of 28 patients had a prostate-specific antigen decrease of more than 50% for at least 8 weeks, compared with two (7%) of 30 patients in the sing le-injection group (group A). The median times to progression of group A and group B were 2.3 months (range, 0 to 12.2 months) and 7.0 months (range, 0 to 24.1 months), respectively (P = .0013), and the median overall survival times were 7.0 months (range, 1.3 to 36.7 months) and 12.7 months (range, 4.1 to 32.2 months), respectively (P = .043). Conclusion: Compared with single-injection therapy, repeated bone-targeted therapy with rhenium-188 HEDP administered to patients with advanced progressive hormone-refractory prostate carcinoma enhanced pain palliation and improved progression-free and overall survival. Larger studies are justified to further evaluate the use of rhenium-188 HEDP. C1 Univ Bonn, Dept Nucl Med, D-53127 Bonn, Germany. Univ Bonn, Dept Urol, D-53127 Bonn, Germany. Univ Bonn, Dept Internal Med Oncol, D-53127 Bonn, Germany. Univ Bonn, Dept Biostat, D-53127 Bonn, Germany. Oak Ridge Natl Lab, Nucl Med Grp, Oak Ridge, TN USA. RP Palmedo, H (reprint author), Univ Bonn, Dept Nucl Med, Siegmund Freud Str 25, D-53127 Bonn, Germany. NR 35 TC 86 Z9 93 U1 0 U2 4 PU AMER SOC CLINICAL ONCOLOGY PI ALEXANDRIA PA 330 JOHN CARLYLE ST, STE 300, ALEXANDRIA, VA 22314 USA SN 0732-183X J9 J CLIN ONCOL JI J. Clin. Oncol. PD AUG 1 PY 2003 VL 21 IS 15 BP 2869 EP 2875 DI 10.1200/JCO.2003.12.060 PG 7 WC Oncology SC Oncology GA 706PJ UT WOS:000184461800010 PM 12885803 ER PT J AU Gritti, F Guiochon, G AF Gritti, F Guiochon, G TI New thermodynamically consistent competitive adsorption isotherm in RPLC SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE adsorption equilibrium; frontal analysis; isotherm modeling; adsorption energy distribution; IAS theory; extended BET isotherm; competitive isotherm; RP-HPLC; toluene; ethylbenzene ID PHASE LIQUID-CHROMATOGRAPHY; BAND PROFILES; SYSTEMS; COLUMN AB A new equation of competitive isotherms was derived in the framework of the ideal adsorbed solution (IAS) that predicts multisolute adsorption isotherms from single-solute isotherms. The IAS theory makes this new isotherm thermodynamically consistent, whatever the saturation capacities of these single-component isotherms. On a Kromasil-C-18 column, with methanol-water (80/20 v/v) as the mobile phase, the best single-solute adsorption isotherm of both toluene and ethylbenzene is the liquid-solid extended multilayer BET isotherm. Despite a significant difference between the monolayer capacities of toluene (370 g/l) and ethylbenzene (170 g/l), the experimental adsorption data fit very well to single-component isotherms exhibiting the same capacities (200 g/l). The new competitive model was used for the modeling of the elution band profiles of mixtures of the two compounds. Excellent agreement between experimental and calculated profiles was observed, suggesting that the behavior of the toluene-ethylbenzene adsorbed phase on the stationary phase is close to ideal. For example, the concentrations measured for the intermediate plateau obtained in frontal analysis differ by less than 2% from those predicted by the IAS model. (C) 2003 Elsevier Inc. 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. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 37 TC 25 Z9 25 U1 2 U2 13 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 AUG 1 PY 2003 VL 264 IS 1 BP 43 EP 59 DI 10.1016/S0021-9797(03)00332-1 PG 17 WC Chemistry, Physical SC Chemistry GA 707TP UT WOS:000184526200007 PM 12885518 ER PT J AU Wakeland, P Khraishi, T Zubia, D AF Wakeland, P Khraishi, T Zubia, D TI An anisotropic elasticity model of strain partitioning in epitaxial thin layers SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 3rd International Conference on Alternative Substrate Technology (ICAST) CY SEP 15-19, 2002 CL CANCUN, MEXICO DE orthorhombic crystals; strain-energy density; misfit dislocations; lattice mismatch; crystal growth ID CRITICAL THICKNESS; PSEUDOMORPHIC STRUCTURES; MODULI AB This work focuses on an anisotropic elasticity treatment of strain partitioning in planar thin layers/films caused by heteroepitaxial crystal growth. In particular, orthotropic materials are considered here. Previous work mostly focused on isotropic elasticity. Here, under the assumption of plane stress and using Hooke's law for linear elasticity, equilibrium equations, and typical strain definitions, one obtains a solution for the strains, in the two planar directions, in the substrate and the epilayer. The strains in a particular layer are expressed as a function of the elastic constants, thicknesses, and lattice parameters of both layers. These results show that the anisotropic solution differs considerably from the isotropic treatment. The current results can also be used to predict the onset of misfit dislocation formation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. Univ Texas, Dept Elect & Comp Engn, El Paso, TX 79968 USA. RP Wakeland, P (reprint author), Sandia Natl Labs, Albuquerque, NM 87185 USA. NR 13 TC 4 Z9 4 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD AUG PY 2003 VL 32 IS 8 BP 836 EP 841 DI 10.1007/s11664-003-0197-9 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 709EB UT WOS:000184610800003 ER PT J AU Inoki, CK Kuan, TS Lee, CD Sagar, A Feenstra, RM Koleske, DD Diaz, DJ Bohn, PW Adesida, I AF Inoki, CK Kuan, TS Lee, CD Sagar, A Feenstra, RM Koleske, DD Diaz, DJ Bohn, PW Adesida, I TI Growth of GaN on porous SiC and GaN substrates SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 3rd International Conference on Alternative Substrate Technology (ICAST) CY SEP 15-19, 2002 CL CANCUN, MEXICO DE GaN; porous SiC; porous GaN; strain ID LAYERS; 6H-SIC(0001); SILICON AB We have studied the growth of GaN on porous SiC and GaN substrates, employing both plasma-assisted molecular-beam epitaxy (PAMBE) and metal-organic chemical-vapor deposition (MOCVD). For growth on porous SiC, transmission electron microscopy (TEM) observations indicate that the epitaxial-GaN growth initiates primarily from surface areas between pores, and the exposed surface pores tend to extend into GaN as open tubes and trap Ga droplets. The dislocation density in the GaN layers is similar to, or slightly less than, that observed in layers grown on nonporous substrates. For the case of GaN growth on porous GaN, the overgrown layer replicates the underlying dislocation structure (although considerable dislocation reduction can occur as this over-growth proceeds, independent of the presence of the porous layer). The GaN layers grown on a porous SiC substrate were found to be mechanically more relaxed than those grown on nonporous substrates; electron-diffraction patterns indicate that the former are free of misfit strain or are even in tension after cooling to room temperature. C1 SUNY Albany, Dept Phys, Albany, NY 12222 USA. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Sandia Natl Labs, Chem Proc Sci Dept, Albuquerque, NM 87185 USA. Univ Illinois, Beckman Inst, Urbana, IL 61801 USA. RP Inoki, CK (reprint author), SUNY Albany, Dept Phys, Albany, NY 12222 USA. RI Feenstra, Randall/P-2530-2014; OI Feenstra, Randall/0000-0001-7120-5685; Inoki, Carlos K./0000-0002-8536-1678 NR 17 TC 43 Z9 45 U1 0 U2 8 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD AUG PY 2003 VL 32 IS 8 BP 855 EP 860 DI 10.1007/s11664-003-0200-5 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 709EB UT WOS:000184610800006 ER PT J AU Guo, YJ Weitsman, YJ AF Guo, YJ Weitsman, YJ TI Closure to "Solution method for beams on nonuniform elastic foundations" by Ya-Jun Guo and Y. Jack Weitsman SO JOURNAL OF ENGINEERING MECHANICS LA English DT Editorial Material C1 Univ Tennessee, Dept Mech & Aerosp Engn & Engn Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Engn Technol, Oak Ridge, TN 37831 USA. RP Guo, YJ (reprint author), Univ Tennessee, Dept Mech & Aerosp Engn & Engn Sci, 307 Perkins Hall, Knoxville, TN 37996 USA. EM Weitsman@utk.edu NR 0 TC 0 Z9 0 U1 1 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-9399 EI 1943-7889 J9 J ENG MECH JI J. Eng. Mech. PD AUG PY 2003 VL 129 IS 8 BP 974 EP 974 DI 10.1061/(ASCE)0733-9399(2003)129:8(974.2) PG 1 WC Engineering, Mechanical SC Engineering GA 704DU UT WOS:000184323400015 ER PT J AU Zheng, Y Barlow, RS Gore, JP AF Zheng, Y Barlow, RS Gore, JP TI Measurements and calculations of spectral radiation intensities for turbulent non-premixed and partially premixed flames SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE combustion; heat transfer; modeling; radiation; turbulence ID NITRIC-OXIDE FORMATION; AIR DIFFUSION FLAMES; HEAT-TRANSFER; JET FLAMES AB Spectral radiation intensities leaving diametric and chord-like paths for six non-sooting flames were measured using an infrared array spectrometer. The spectral radiation intensities were also computed using the mean property approach and a time and space series simulation approach. Turbulence/radiation interactions (TRI) in these flames were investigated by comparing the two sets of computations to the experimental data. The effects of TRI are significant for regions away from the flame axis. The new data and findings are of value in the evaluation of radiation models, which are increasingly used in turbulent combustion calculations. C1 Purdue Univ, Sch Mech Engn, Maurice J Zucrow Labs, W Lafayette, IN 47907 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Zheng, Y (reprint author), Purdue Univ, Sch Mech Engn, Maurice J Zucrow Labs, W Lafayette, IN 47907 USA. NR 23 TC 27 Z9 27 U1 0 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD AUG PY 2003 VL 125 IS 4 BP 678 EP 686 DI 10.1115/1.1589502 PG 9 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 709DY UT WOS:000184610500022 ER PT J AU Davoudiasl, H Hewett, JL Rizzo, TG AF Davoudiasl, H Hewett, JL Rizzo, TG TI Brane localized curvature for warped gravitons. SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE extra large dimensions; beyond standard model ID EXTRA DIMENSIONS; GAUGE FIELD; PHENOMENOLOGY; HIERARCHY; MODULUS AB We study the effects of including brane localized curvature terms in the Randall-Sundrum (RS) model of the hierarchy. This leads to the existence of brane localized kinetic terms for the graviton. Such terms can be induced by brane and bulk quantum effects as well as Higgs-curvature mixing on the brane. We derive the modified spectrum of Kaluza-Klein (KK) gravitons and their couplings to 4-dimensional fields in the presence of these terms. We find that the masses and couplings of the KK gravitons have considerable dependence on the size of the brane localized terms; the weak-scale phenomenology of the model is consequently modified. In particular, the weak-scale spin-2 graviton resonances which generically appear in the RS model may be significantly lighter than previously assumed. However, they may avoid detection as their widths may be too narrow to be observable at colliders. In the contact interaction limit, for a certain range of parameters, the experimental reach for the scale of the theory is independent of the size of the boundary terms. C1 Inst Adv Study, Sch Nat Sci, Princeton, NJ 08540 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Inst Adv Study, Sch Nat Sci, Olden Lane, Princeton, NJ 08540 USA. EM hooman@ias.edu; hewett@slac.stanford.edu; rizzo@slac.stanford.edu NR 30 TC 24 Z9 24 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 AUG PY 2003 IS 8 AR 034 DI 10.1088/1126-6708/2003/08/034 PG 16 WC Physics, Particles & Fields SC Physics GA 737XR UT WOS:000186258100034 ER PT J AU Gimon, EG Hashimoto, A Lunin, O Hubeny, VE Rangamani, M AF Gimon, EG Hashimoto, A Lunin, O Hubeny, VE Rangamani, M TI Black strings in asymptotically plane wave geometries SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE black holes in string theory; Penrose limit and pp-wave background ID PP-WAVE; BACKGROUNDS; HOLES AB We present a class of black string spacetimes which asymptote to maximally symmetric plane wave geometries. Our construction will rely on a solution generating technique, the null Melvin twist, which deforms an asymptotically flat black string spacetime to an asymptotically plane wave black string spacetime while preserving the event horizon. C1 Inst Adv Study, Princeton, NJ 08540 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Inst Adv Study, Olden Lane, Princeton, NJ 08540 USA. EM gimon@ias.edu; aki@ias.edu; lunin@ias.edu; veronika@itp.stanford.edu; mukund@socrates.berkeley.edu NR 25 TC 57 Z9 57 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 AUG PY 2003 IS 8 AR 035 PG 15 WC Physics, Particles & Fields SC Physics GA 737XR UT WOS:000186258100035 ER PT J AU Hewett, JL Rizzo, TG AF Hewett, JL Rizzo, TG TI Shifts in the properties of the Higgs boson from radion mixing SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE extra large dimensions; beyond standard model; Higgs physics ID STABILIZED MODULUS; PHENOMENOLOGY; HIERARCHY; GRAVITY; MODEL; MASS; LHC AB We examine how mixing between the Standard Model Higgs boson, h, and the radion present in the Randall-Sundrum model of localized gravity modifies the expected properties of the Higgs boson. In particular, we demonstrate that the total and partial decay widths of the Higgs, as well as the h --> gg branching fraction, can be substantially altered from their Standard Model expectations. The remaining branching fractions are modified less than less than or similar to 5% for most of the parameter space volume. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM rizzo@slac.stanford.edu NR 28 TC 34 Z9 34 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 AUG PY 2003 IS 8 AR 028 DI 10.1088/1126-6708/2003/08/028 PG 11 WC Physics, Particles & Fields SC Physics GA 737XR UT WOS:000186258100028 ER PT J AU Rizzo, TG AF Rizzo, TG TI More transverse polarization signatures of extra dimensions at linear colliders SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE extra large dimensions; beyond standard model ID E+E-COLLISIONS; HIERARCHY; SIGNALS; PHENOMENOLOGY; LEPTOQUARKS; MILLIMETER; GRAVITY; LIMITS; MODEL; TEV AB Polarization of both electron and positron beams at a future linear collider (LC) allows for the measurement of transverse polarization asymmetries. These asymmetries have been shown to be particularly sensitive to graviton or other spin-2, s-channel exchanges in the process e(+)e(-) --> f (f) over bar (f not equal e) which allows for a doubling of the usual search reach. A question then arises as to whether other e(+)e(-) processes also show comparable sensitivity. Here we extend our previous analysis to the set of final states e(+)e(-), W+W-, 2gamma and 2Z as well as to the Moller scattering process e(-)e(-) --> e(-)e(-). We demonstrate that these reactions yield transverse polarization asymmetries which are somewhat less sensitive to graviton exchange than are those obtained in our earlier analysis for e(+)e(-) --> f (f) over bar. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM rizzo@slac.stanford.edu NR 47 TC 8 Z9 8 U1 0 U2 2 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 AUG PY 2003 IS 8 AR 051 PG 14 WC Physics, Particles & Fields SC Physics GA 737XR UT WOS:000186258100051 ER PT J AU Lemke, SL Dueker, SR Follett, JR Lin, YM Carkeet, C Buchholz, BA Vogel, JS Clifford, AJ AF Lemke, SL Dueker, SR Follett, JR Lin, YM Carkeet, C Buchholz, BA Vogel, JS Clifford, AJ TI Absorption and retinol equivalence of beta-carotene in humans is influenced by dietary vitamin A intake SO JOURNAL OF LIPID RESEARCH LA English DT Article DE accelerator mass spectrometry; isotope; kinetic ID ACCELERATOR MASS-SPECTROMETRY; 3 URINARY METABOLITES; INTESTINAL-ABSORPTION; EXCENTRIC CLEAVAGE; NUTRITIONAL-STATUS; ACID; RAT; BIOAVAILABILITY; CONVERSION; TISSUES AB The effect of vitamin A, supplements on metabolic behavior of an oral tracer dose of [C-14]beta-carotene was investigated in a longitudinal test-retest design in two adults. For the test, each subject ingested 1 nmol of [C-14]beta-carotene (100 nCi) in an emulsified olive oil-banana drink. Total urine and stool were collected for up to 30 days; concentration-time patterns of [C-14]beta-carotene, [C-14]retinyl esters, and [C-14]retinol were determined for 46 days. On Day 53, the subjects were placed on a daily vitamin A supplement (10,000 IU/day), and a second dose of [C-14]beta-carotene (retest) was given on Day 74. All C-14 determinations were made using accelerator mass spectrometry. In both subjects, the vitamin A supplementation was associated with three main effects: 1) increased apparent absorption: test versus retest values rose from 57% to 74% (Subject 1) and from 52% to 75% (Subject 2); 2) an similar to10-fold reduction in urinary excretion; and 3) a lower ratio of labeled retinyl ester/beta-carotene concentrations in the absorptive phase. The molar vitamin A value of the dose for the test was 0.62 mot (Subject 1) and 0.54 mot (Subject 2) vitamin A to 1 mot beta-carotene. Respective values for the retest were 0.85 and 0.74. jlr These results show that while less cleavage of beta-carotene occurred due to vitamin A supplementation, higher absorption resulted in larger molar vitamin A values. C1 Univ Calif Davis, Dept Nutr, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. RP Dueker, SR (reprint author), Univ Calif Davis, Dept Nutr, 1 Shields Ave, Davis, CA 95616 USA. RI Buchholz, Bruce/G-1356-2011 FU NCRR NIH HHS [P41 RR013461, RR-13461]; NIDDK NIH HHS [DK48307] NR 50 TC 42 Z9 45 U1 1 U2 8 PU LIPID RESEARCH INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0022-2275 J9 J LIPID RES JI J. Lipid Res. PD AUG PY 2003 VL 44 IS 8 BP 1591 EP 1600 DI 10.1194/jlr.M300116-JLR200 PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 709WX UT WOS:000184650500021 PM 12777466 ER PT J AU Narehood, DG Grube, N Dimeo, RM Brown, DW Sokol, PE AF Narehood, DG Grube, N Dimeo, RM Brown, DW Sokol, PE TI Inelastic neutron scattering of H-2 in xerogel SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article DE xerogel; inelastic neutron scattering; kinetic energy ID POROUS VYCOR GLASS; HE-4; HYDROGEN; LIQUID AB The properties of molecular hydrogen adsorbed in Britesorb were studied through inelastic neutron scattering. We have measured both the rotational energy levels and the momentum distribution at bilayer and nearly full pore fillings. Splitting of the J=1 rotational energy levels is observed for molecular hydrogen adsorbed on the surface, while the rotational properties of the hydrogen adsorbed after monolayer completion is consistent with behavior in the bulk. Additionally, the measurement of the momentum distribution showed that the mean kinetic energy of the molecules in the bilayer is 88 K +/- 7 K. The kinetic energy measured in the nearly full pore was 81 K +/- 6 K, which is consistent with a simple model in which the behavior of the monolayer is dominated by the interaction with the surface of the pore wall but H-2 adsorbed after monolayer completion is bulk like. C1 Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Penn State Univ, Inst Mat Res, University Pk, PA 16802 USA. Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. Los Alamos Natl Lab, Div Sci Mat, Los Alamos, NM 87545 USA. RP Narehood, DG (reprint author), Penn State Univ, Dept Phys, University Pk, PA 16802 USA. NR 22 TC 3 Z9 3 U1 1 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD AUG PY 2003 VL 132 IS 3-4 BP 223 EP 237 DI 10.1023/A:1024461601413 PG 15 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 693EP UT WOS:000183703700004 ER PT J AU van Lierop, J Schofield, MA Lewis, LH Gambino, RJ AF van Lierop, J Schofield, MA Lewis, LH Gambino, RJ TI Exchange bias in a thin film dispersion of MnO nanocrystallites in Co SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE exchange bias; thin film; nanocrystal ID ANTIFERROMAGNETIC RESONANCE; MAGNETIC-BEHAVIOR; ANISOTROPY; NIO AB Unusually large magnetization loops shifts along the field axis, of the same order as those observed in the archetypical exchange biased system Co/CoO, have been measured in a Co/MnO thin film made using reactive ion beam assisted deposition. These large loop shifts are unexpected for a system with an antiferromagnetic anisotropy that is two orders of magnitude less than that of CoO. This magnetic behavior is attributed to the nanoscale nature of the crystallites that constitute the film, where the surface area to volume ratio is large enough so that a sizable surface magnetic contribution provides the necessary antiferromagnet to ferromagnet coupling for the large measured exchange bias. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Mat Sci, Upton, NY 11973 USA. SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. RP van Lierop, J (reprint author), Univ Michigan, Dept Phys, 500 E Univ Ave, Ann Arbor, MI 48109 USA. NR 25 TC 13 Z9 13 U1 0 U2 4 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 AUG PY 2003 VL 264 IS 2-3 BP 146 EP 152 DI 10.1016/S0304-8853(03)00178-1 PG 7 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 711QV UT WOS:000184753300005 ER PT J AU Weston, JL Brisbin, IL AF Weston, JL Brisbin, IL TI Demographics of a protected population of gray foxes (Urocyon cinereoargenteus) in South Carolina SO JOURNAL OF MAMMALOGY LA English DT Article DE age structure; demographics; gray fox; reproduction; sex ratio; Urocyon cinereoargenteus ID AGE-DETERMINATION; HETEROGENEITY; MORTALITY; RACCOONS AB We studied demographics of a population of gray foxes (Urocyon cinereoargenteus) that has been protected for over 50 years on the United States Department of Energy's Savannah River Site, near Aiken, South Carolina. The percentages of individuals in the 10-, 22-, and greater than or equal to34-month-old age classes were 37.2, 10.3, and 52.6, respectively. This differed significantly from age structure at this same site in 1954-1956. Sex ratio was biased toward females (58.7%). Average litter size was 3.6 +/- 0.2 SE, and the barren rate was 11.1%. The greater proportion of females, however, resulted in an overall per capita reproductive rate that was still comparable with populations subject to harvest pressure. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Weston, JL (reprint author), Univ S Carolina, Peromyscus Genet Stock Ctr, Dept Biol Sci, Columbia, SC 29208 USA. NR 34 TC 6 Z9 6 U1 1 U2 11 PU ALLIANCE COMMUNICATIONS GROUP DIVISION ALLEN PRESS PI LAWRENCE PA 810 EAST 10TH STREET, LAWRENCE, KS 66044 USA SN 0022-2372 J9 J MAMMAL JI J. Mammal. PD AUG PY 2003 VL 84 IS 3 BP 996 EP 1005 DI 10.1644/BOS-037 PG 10 WC Zoology SC Zoology GA 718MC UT WOS:000185149300020 ER PT J AU Gao, F Weber, WJ AF Gao, F Weber, WJ TI Atomic-scale simulations of cascade overlap and damage evolution in silicon carbide SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID IRRADIATION-INDUCED AMORPHIZATION; SIC SINGLE-CRYSTALS; AMORPHOUS TRANSITION; TOPOLOGICAL DISORDER; DEFECT PRODUCTION; CERAMICS; RECRYSTALLIZATION; IMMOBILIZATION; RECOVERY AB In a previous computer-simulation experiment, the accumulation of damage in silicon carbide (SiC) from the overlap of 10 keV Si displacement cascades at 200 K was investigated, and the damage states produced following each cascade were archived for further analysis. In the current study, interstitial clustering, system energy, and volume changes are investigated as the damage states evolve due to cascade overlap. An amorphous state is achieved at a damage energy density of 27.5 eV/atom (0.28 displacements per atom). At low-dose levels, most defects are produced as isolated Frenkel pairs, with a small number of defect clusters involving only four to six atoms; however, after the overlap of five cascades (0.0125 displacements per atom), the size and number of interstitial clusters increases with increasing dose. The average energy per atom increases linearly with increasing short-range (or chemical) disorder. The volume change exhibits two regimes of linear dependence on system energy and increases more rapidly with dose than either the energy or the disorder, which indicates a significant contribution to swelling of isolated interstitials and antisite defects. The saturation volume change for the cascade-amorphized state in these simulations is 8.2%, which is in reasonable agreement with the experimental value of 10.8% in neutron-irradiated SiC. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gao, F (reprint author), Pacific NW Natl Lab, MS K8-93,POB 999, Richland, WA 99352 USA. EM fei.gao@pnl.gov RI Weber, William/A-4177-2008; Gao, Fei/H-3045-2012 OI Weber, William/0000-0002-9017-7365; NR 36 TC 17 Z9 17 U1 2 U2 10 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0884-2914 EI 2044-5326 J9 J MATER RES JI J. Mater. Res. PD AUG PY 2003 VL 18 IS 8 BP 1877 EP 1883 DI 10.1557/JMR.2003.0262 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 709EF UT WOS:000184611200023 ER PT J AU Zhu, YT Huang, JY Gubicza, J Ungar, T Wang, YM Ma, E Valiev, RZ AF Zhu, YT Huang, JY Gubicza, J Ungar, T Wang, YM Ma, E Valiev, RZ TI Nanostructures in Ti processed by severe plastic deformation SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID GRAIN-BOUNDARY STRUCTURE; CRYSTALLITE SIZE DISTRIBUTION; X-RAY-DIFFRACTION; MECHANICAL-BEHAVIOR; NANOCRYSTALLINE METALS; THERMAL-STABILITY; SINGLE-CRYSTALS; ALPHA-TITANIUM; PURE TI; AL-MG AB Metals and alloys processed by severe plastic deformation (SPD) can demonstrate superior mechanical properties, which are rendered by their unique defect structures. In this investigation, transmission electron microscopy and x-ray analysis were used to systematically study the defect structures, including grain and subgrain structures, dislocation cells, dislocation distributions, grain boundaries, and the hierarchy of these structural features, in nanostructured Ti produced by a two-step SPD procedure-warm equal channel angular pressing followed by cold rolling. The effects of these defect structures on the mechanical behaviors of nanostructured Ti are discussed. C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Eotvos Lorand Univ, Dept Gen Phys, H-1518 Budapest, Hungary. Johns Hopkins Univ, Dept Mat Sci & Engn, Baltimore, MD 21218 USA. Ufa State Aviat Tech Univ, Inst Phys Adv Mat, Ufa 450000, Russia. RP Zhu, YT (reprint author), Los Alamos Natl Lab, Div Mat Sci & Technol, MS G755, Los Alamos, NM 87545 USA. RI Zhu, Yuntian/B-3021-2008; Ma, En/A-3232-2010; Huang, Jianyu/C-5183-2008; Wang, Yinmin (Morris)/F-2249-2010 OI Zhu, Yuntian/0000-0002-5961-7422; Wang, Yinmin (Morris)/0000-0002-7161-2034 NR 59 TC 156 Z9 161 U1 5 U2 50 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD AUG PY 2003 VL 18 IS 8 BP 1908 EP 1917 DI 10.1557/JMR.2003.0267 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 709EF UT WOS:000184611200028 ER PT J AU Wang, XY Lee, BI Hu, MZ Payzant, EA Blom, DA AF Wang, XY Lee, BI Hu, MZ Payzant, EA Blom, DA TI Mechanism of nanocrystalline BaTiO3 particle formation by hydrothermal refluxing synthesis SO JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS LA English DT Article ID BARIUM-TITANATE POWDERS; AQUEOUS SYNTHESIS LTAS; TEMPERATURE SYNTHESIS; TETRAGONAL BATIO3; FINE PARTICLES; LTDS METHOD; CRYSTALLITES; METATITANATE; PRECURSORS; EVOLUTION AB The nanocrystal-formation mechanisms of barium titanate (BaTiO3) particles in a hydrothermal refluxing process have been studied. The refluxing method allows in situ sampling and requires ambient conditions (i.e., temperature below the boiling point of solvent and atmospheric pressure). It was found that the formation of BaTiO3 from the amorphous precursor was a very rapid process. BaTiO3 nuclei were formed at around 75degreesC, 15 min after the beginning of the hydrothermal reaction. Individual BaTiO3 particles with dimensions in the range of 70-130 nm were formed 5 min after the nucleation of nanocrystals. Further reaction for crystal growth proceeded by consumption of the remaining precursors and possible aggregation of BaTiO3 particles via Ostwald ripening. It is proposed on the basis of the microscopic observations that the in situ transformation mechanism, rather than dissolution-precipitation mechanism, is dominant in the early stage of BaTiO3 formation. (C) 2003 Kluwer Academic Publishers. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Clemson Univ, Sch Mat Sci & Engn, Clemson, SC 29634 USA. RP Hu, MZ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Payzant, Edward/B-5449-2009; OI Payzant, Edward/0000-0002-3447-2060; Hu, Michael/0000-0001-8461-9684 NR 44 TC 25 Z9 27 U1 1 U2 10 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0957-4522 J9 J MATER SCI-MATER EL JI J. Mater. Sci.-Mater. Electron. PD AUG PY 2003 VL 14 IS 8 BP 495 EP 500 DI 10.1023/A:1023920902217 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA 684KJ UT WOS:000183205600006 ER PT J AU Goldhaber, AS AF Goldhaber, AS TI Fractional charge definitions and conditions SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Article ID MASSIVE GAUGE-THEORIES; EFFECT QUASI-PARTICLES; HALF-INTEGRAL CHARGE; TOPOLOGICAL CHARGES; VACUUM POLARIZATION; MAGNETIC MONOPOLES; LOCAL CHARGE; FIELD-THEORY; Q-BALLS; SOLITONS AB The phenomenon of fractional charge has come to prominence in recent decades through theoretical and experimental discoveries of isolable objects which carry fractions of familiar charge units-electric charge Q, spin S, baryon number B and lepton number L. It is shown here on the basis of a few simple assumptions that all these effects may be described using a generalized version of charge renormalization for locally conserved charges, in which many-body correlations can produce familiar adiabatic, continuous renormalization, and in some circumstances nonadiabatic, discrete renormalization. The fractional charges may be carried either by fundamental particles or by fundamental solitons. This excludes nontopological solitons and also skyrmions: The only known fundamental solitons in three or fewer space dimensions d are the kink (d=1), the vortex (d=2), and the magnetic monopole (d=3). Further, for a charge which is not intrinsically coupled to the topological charge of a soliton, only the kink and the monopole may carry fractional values. The same reasoning enforces fractional local values of B-L for electrically charged elementary particles. (C) 2003 American Institute of Physics. C1 SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. Stanford Linear Accelerator Ctr, Theoret Phys Grp, Menlo Pk, CA 94025 USA. MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. RP Goldhaber, AS (reprint author), SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. NR 88 TC 2 Z9 2 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0022-2488 J9 J MATH PHYS JI J. Math. Phys. PD AUG PY 2003 VL 44 IS 8 BP 3607 EP 3618 DI 10.1063/1.1586793 PG 12 WC Physics, Mathematical SC Physics GA 703WN UT WOS:000184305200026 ER PT J AU Sunner, J Avci, R Richards, L Groenewold, G Ingram, J Arthun, M AF Sunner, J Avci, R Richards, L Groenewold, G Ingram, J Arthun, M TI Preservation of yeast cell morphology for scanning electron microscopy using 3.28-mu m IR laser irradiation SO JOURNAL OF MICROBIOLOGICAL METHODS LA English DT Article DE SENT; electron microscopy; yeast cells; imaging; fixation; dehydration; infrared laser; IR; morphology AB As an alternative to conventional fixation procedures for scanning electron microscopy (SEM) analysis, yeast cells (Saccharomyces cerevisiae) were irradiated in ambient air, with an intense 3.28-mum IR laser pulse. The morphology of the irradiated cells was well preserved, while nonirradiated control cells were severely shriveled. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Montana State Univ, Dept Chem & Biochem, Bozeman, MT 59717 USA. Montana State Univ, Dept Phys, ICAL, Bozeman, MT 59717 USA. Montana State Univ, Dept Chem Engn, Bozeman, MT 59717 USA. INEEL, Idaho Falls, ID 83415 USA. RP Sunner, J (reprint author), Montana State Univ, Dept Chem & Biochem, Bozeman, MT 59717 USA. NR 3 TC 3 Z9 3 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-7012 J9 J MICROBIOL METH JI J. Microbiol. Methods PD AUG PY 2003 VL 54 IS 2 BP 285 EP 287 DI 10.1016/S0167-7012(03)00041-1 PG 3 WC Biochemical Research Methods; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA 691DW UT WOS:000183590400016 PM 12782385 ER PT J AU Gardino, AK Volkman, BF Cho, HS Lee, SY Wemmer, DE Kern, D AF Gardino, AK Volkman, BF Cho, HS Lee, SY Wemmer, DE Kern, D TI The NMR solution structure of BeF3--activated Spo0F reveals the conformational switch in a phosphorelay system SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE response regulator; two-component systems; phosphorelay; Spo0F; NMR spectroscopy ID SUBTILIS RESPONSE REGULATOR; HIGH-RESOLUTION NMR; BACILLUS-SUBTILIS; MOLECULAR RECOGNITION; SIGNAL-TRANSDUCTION; CHEMICAL-SHIFT; BACTERIAL CHEMOTAXIS; SECONDARY STRUCTURE; PROTEIN; PHOSPHORYLATION AB Two-component systems, which are comprised of a single histidine-aspartate phosphotransfer module, are the dominant signaling pathways in bacteria and have recently been identified in several eukaryotic organisms as well. A tandem connection of two or more histidine-aspartate motifs forms complex phosphorelays. While response regulators from simple two-component systems have been characterized structurally in their inactive and active forms, we address here the question of whether a response regulator from a phosphorelay has a distinct structural basis of activation. We report the NMR solution structure of BeF3--activated Spo0F, the first structure of a response regulator from a phosphorelay in its activated state. Conformational changes were found in regions previously identified to change in simple two-component systems. In addition, a downward shift by half a helical turn in helix 1, located on the opposite side of the common activation surface, was observed as a consequence of BeF3- activation. Conformational changes in helix 1 can be rationalized by the distinct function of phosphoryl transfer to the second histidine kinase, Spo0B, because helix 1 is known to interact directly with Spo0B and the phosphatase RapB. The identification of structural rearrangements in Spo0F supports the hypothesis of a pre-existing equilibrium between the inactive and active state prior to phosphorylation that was suggested on the basis of previous NMR dynamics studies on Spo0F. A shift of a pre-existing equilibrium is likely a general feature of response regulators. (C) 2003 Elsevier Ltd. All rights reserved. C1 Brandeis Univ, Dept Biochem, Waltham, MA 02453 USA. Med Coll Wisconsin, Dept Biochem, Milwaukee, WI 53226 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Kern, D (reprint author), Brandeis Univ, Dept Biochem, Waltham, MA 02453 USA. FU NCRR NIH HHS [RR02301, RR02781, RR08438]; NIGMS NIH HHS [GM62117, GM62163, GM66326] NR 34 TC 32 Z9 32 U1 0 U2 2 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD AUG 1 PY 2003 VL 331 IS 1 BP 245 EP 254 DI 10.1016/S0022-2836(03)00733-2 PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 704QL UT WOS:000184351300019 PM 12875849 ER PT J AU Stanger, KJ Tang, YL Anderegg, J Angelici, RJ AF Stanger, KJ Tang, YL Anderegg, J Angelici, RJ TI Arene hydrogenation using supported rhodium metal catalysts prepared from [Rh(COD)H](4), [Rh(COD)(2)]+BF4-, and [Rh(COD)CI](2) adsorbed on SiO2 and Pd-SiO2 SO JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL LA English DT Article DE immobilized metal catalysts; rhodium; arene hydrogenation; TCSM; silica; palladium; XPS; TEM; mercury poisoning ID PALLADIUM HETEROGENEOUS CATALYST; MILD CONDITIONS; BENZENE HYDROGENATION; SILICA; COMPLEXES; RH; GENERATION; IRIDIUM(I); OXIDATION; ALUMINA AB Four different rhodium precursors, [Rh(COD)H](4), [Rh(COD)(2)]+BF4-, [Rh(COD)Cl](2), and RhCl3.3H(2)O, adsorbed onto silica (SiO2) or onto palladium supported on silica (Pd-SiO2), were examined for their catalytic arene hydrogenation activities. Rates of toluene hydrogenation were compared when the catalysts were pretreated with hydrogen as follows: none, 40degreesC for 24 h. and 200 degreesC for 4 h. With no hydrogen pretreatment, the rhodium precursors adsorbed on Pd-SiO2 showed higher activities than the corresponding precursors on only SiO2. As the hydrogen pretreatment temperature was increased, the activities of the catalysts on SiO2 increased; the highest activity occurred with catalysts pretreated at 200 degreesC. Conversely, milder pretreatments were more effective for the catalysts on Pd-SiO2; higher temperature pretreatments reduced activities. The catalysts were characterized by their activities, diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). All of the studies indicate that the active catalytic species is rhodium metal. On silica, H-2 reduction of the rhodium complex to Rh metal under arene hydrogenation conditions was slow in all cases except [Rh(COD)H](4). However, on Pd-SiO2, the palladium accelerated the reduction of all of the Rh complex precursors to rhodium metal under the same conditions. The resulting Rh-Pd-SiO2 bimetallic catalysts exhibited higher activities than catalysts of the same composition prepared by classical methods. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Ames Lab, Dept Chem, Ames, IA 50011 USA. RP Iowa State Univ Sci & Technol, Ames Lab, Dept Chem, Gilman Hall, Ames, IA 50011 USA. EM angelici@iastate.edu NR 39 TC 24 Z9 24 U1 1 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1381-1169 EI 1873-314X J9 J MOL CATAL A-CHEM JI J. Mol. Catal. A-Chem. PD AUG 1 PY 2003 VL 202 IS 1-2 BP 147 EP 161 DI 10.1016/S1381-1169(03)00198-5 PG 15 WC Chemistry, Physical SC Chemistry GA 700FW UT WOS:000184102800015 ER PT J AU Liu, G Rodriguez, JA Hrbek, J Long, BT Chen, DA AF Liu, G Rodriguez, JA Hrbek, J Long, BT Chen, DA TI Interaction of thiophene with stoichiometric and reduced rutile TiO2(110) surfaces: role of Ti3+ sites in desulfurization activity SO JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL LA English DT Article DE adsorption; TiO2(110); thiophene; TDS; XPS; density-functional theory; desulfurization ID SELF-ASSEMBLED MONOLAYERS; TOTAL-ENERGY CALCULATIONS; MIXED-METAL OXIDES; DEFECTIVE TIO2(110); HYDRODESULFURIZATION CATALYSTS; PHOTOELECTRON-SPECTROSCOPY; ELECTRONIC-STRUCTURE; SULFIDED MOLYBDENUM; SUPPORTED CATALYSTS; PLANE-WAVE AB The adsorption of thiophene (C4H4S) on almost stoichiometric TiO2(110) and defective TiO2-x(110) surfaces has been studied with a combination of synchrotron-based high-resolution photoemission spectroscopy, thermal desorption mass spectrometry (TDS), and first-principles density-functional (DF) slab calculations. The bonding nature between C4H4S and Ti or O sites of TiO2(110), and point defects (oxygen vacancies) of TiO2-x(110) was investigated. Over an almost stoichiometric TiO2(110) surface, the adsorption and desorption of C4H4S is completely reversible. In the submonolayer regime, four adsorption states in the temperature range of 150-450 K were identified in TDS. No thiophene decomposition was observed up to 800 K under ultra-high vacuum (UHV) conditions. The results of DF calculations indicate that at small coverage the molecule should be bonded with its ring nearly parallel to the surface. At high coverages of thiophene, bonding through the S atom becomes more stable because it reduces adsorbate <----> adsorbate repulsion. On a defective TiO2-x(110) surface with similar to45% of Ti3+ and T2+, a small fraction of the adsorbed thiophene molecules (<0.05 ML) decomposed. Our experimental and theoretical studies indicate that the vacancy states of TiO2-x(110) interact poorly with the LUMO of thiophene. This is a behavior opposite to that found for the adsorption of S-2, CH3S and SO2. The role of Ti3+ sites in the desulfurization activity of MoSx/TiO2 catalysts is analyzed in light of these results. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Univ S Carolina, Dept Biochem & Chem, Columbia, SC 29208 USA. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, POB 5000, Upton, NY 11973 USA. RI Hrbek, Jan/I-1020-2013; OI Chen, Donna A./0000-0003-4962-5530 NR 64 TC 38 Z9 38 U1 1 U2 32 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1381-1169 J9 J MOL CATAL A-CHEM JI J. Mol. Catal. A-Chem. PD AUG 1 PY 2003 VL 202 IS 1-2 BP 215 EP 227 DI 10.1016/S1381-1169(03)00206-1 PG 13 WC Chemistry, Physical SC Chemistry GA 700FW UT WOS:000184102800021 ER PT J AU Dupuis, M Schenter, GK Garrett, BG Arcia, EE AF Dupuis, M Schenter, GK Garrett, BG Arcia, EE TI Potentials of mean force with ab initio mixed Hamiltonian models of solvation SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article DE Hamiltonian models; solute; solvent; mixed Hamiltonians; potential of mean force; solute; solvent ID STATISTICAL-MECHANICAL TREATMENT; POLARIZABLE CONTINUUM MODEL; 1ST-PRINCIPLES MOLECULAR-DYNAMICS; ENERGY PERTURBATION METHOD; REACTION FIELD-THEORY; COMBINED QUANTUM; ELECTRONIC-STRUCTURE; WATER MOLECULE; LIQUID WATER; EXCITED-STATES AB We give an account of a computationally tractable and efficient procedure for the calculation of potentials of mean force using mixed Hamiltonian models of electronic structure where quantum subsystems are described with computationally intensive ab initio wavefunctions. The mixed Hamiltonian is mapped into an all-classical Hamiltonian that is amenable to a thermodynamic perturbation treatment for the calculation of free energies. A small number of statistically uncorrelated (solute-solvent) configurations are selected from the Monte Carlo random walk generated with the all-classical Hamiltonian approximation. Those are used in the averaging of the free energy using the mixed quantum/classical Hamiltonian. The methodology is illustrated for the micro-solvated S(N)2 substitution reaction of methyl chloride by hydroxide. We also compare the potential of mean force calculated with the above protocol with an approximate formalism, one in which the potential of mean force calculated with the all-classical Hamiltonian is simply added to the energy of the isolated (non-solvated) solute along the reaction path. Interestingly the latter approach is found to be in semi-quantitative agreement with the full mixed Hamiltonian approximation. (C) 2003 Elsevier B.V. All rights reserved. C1 Pacific NW Natl Lab, Div Chem Sci, Richland, WA 99352 USA. RP Dupuis, M (reprint author), Pacific NW Natl Lab, Div Chem Sci, K1-83,PO 999,906 Battelle Blvd, Richland, WA 99352 USA. EM michel.dupuis@pnl.gov RI Schenter, Gregory/I-7655-2014 OI Schenter, Gregory/0000-0001-5444-5484 NR 78 TC 9 Z9 9 U1 3 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 J MOL STRUC-THEOCHEM JI Theochem-J. Mol. Struct. PD AUG 1 PY 2003 VL 632 SI SI BP 173 EP 183 DI 10.1016/S0166-1280(03)00297-5 PG 11 WC Chemistry, Physical SC Chemistry GA 722VQ UT WOS:000185399100014 ER PT J AU Miller, MK Russell, KF Sokolov, MA Nanstad, RK AF Miller, MK Russell, KF Sokolov, MA Nanstad, RK TI Atom probe tomography of radiation-sensitive characterization KS-01 weld SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID PRESSURE-VESSEL STEELS AB The microstructure of a radiation-sensitive KS-01 test weld has been characterized by atom probe tomography. The levels of copper, manganese, nickel and chromium in this weld were amongst the highest of all the steels used in Western reactor pressure vessels. After neutron irradiation to a fluence of 0.8 x 10(23) nm(-2) (E > 1 MeV) at a temperature of 288 degreesC, this weld exhibited a large Charpy T-41j shift of 169 K, a large shift of the fracture toughness transition temperature of 160 K. a decrease in upper shelf energy from 118 to similar to78 J, and an increase in the yield strength from 600 to 826 MPa. However, the mechanical properties data conformed to the master curve. Atom probe tomography revealed a high number density (similar to3 x 10(24) m(-3)) Of Cu-, Mn-, Ni-, Si- and P-enriched precipitates and a lower number density (similar to1 x 10(23) m(-3)) of P clusters. (C) 2003 Elsevier B.V. All rights reserved. C1 Oak Ridge Natl Lab, Microscopy Microanal Microstruct Grp, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Radiat Mat Sci & Technol Grp, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Miller, MK (reprint author), Oak Ridge Natl Lab, Microscopy Microanal Microstruct Grp, Div Met & Ceram, POB 2008,Bldg 4500S, Oak Ridge, TN 37831 USA. NR 16 TC 26 Z9 29 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD AUG 1 PY 2003 VL 320 IS 3 BP 177 EP 183 DI 10.1016/S0022-3115(03)00108-9 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 709CX UT WOS:000184608100001 ER PT J AU Helean, KB Navrotsky, A Lumpkin, GR Colella, M Lian, J Ewing, RC Ebbinghaus, B Catalano, JG AF Helean, KB Navrotsky, A Lumpkin, GR Colella, M Lian, J Ewing, RC Ebbinghaus, B Catalano, JG TI Enthalpies of formation of U-, Th-, Ce-brannerite: implications for plutonium immobilization SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID HEAVY-ION IRRADIATION; PYROCHLORE; CALORIMETRY; CERAMICS; UTI2O6; WASTE AB Brannerite, ideally MTi2O6, (M = actinides, lanthanides and Ca) occurs in titanate-based ceramics proposed for the immobilization of plutonium. Standard enthalpies of formation, DeltaH(f)(0) at 298 K, for three brannerite compositions (kJ/ mol): CeTi2O6 (-2948.8 +/- 4.3), U0.97Ti2.03O6 (-2977.9 +/- 3.5) and ThTi2O6 (-3096.5 +/- 4.3) were determined by high temperature oxide melt drop solution calorimetry at 975 K using 3Na(2)O . 4MoO(3) solvent. The enthalpies of formation were also calculated from an oxide phase assemblage (DeltaH(f-ox)(0) at 298 K): MO2 + 2TiO(2) = MTi2O6, Only UTi2O6 is energetically stable with respect to an oxide assemblage: U0.97Ti2.03O6 (DeltaH(f-ox)(0) = -7.7 +/- 2.8 kJ/mol). Both CeTi2O6 and ThTi2O6 are higher in enthalpy with respect to their oxide assemblages with (DeltaH(f-ox)(0) = +29.4 +/- 3.6 kJ/mol) and (DeltaH(f-ox)(0) = +19.4 +/- 1.6 kJ/mol) respectively. Thus, Ce- and Th-brannerite are entropy stabilized and are thermodynamically stable only at high temperature. (C) 2003 Elsevier B.V. All rights reserved. C1 Univ Calif Davis, Dept Chem Engn & Mat Sci, Thermochem Facil, Davis, CA 95616 USA. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Univ Michigan, Dept Nucl Engn & Radiol Sci, Ann Arbor, MI 48109 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. RP Helean, KB (reprint author), Univ Calif Davis, Dept Chem Engn & Mat Sci, Thermochem Facil, Davis, CA 95616 USA. RI Lumpkin, Gregory/A-7558-2008; Lian, Jie/A-7839-2010; Catalano, Jeffrey/A-8322-2013 OI Catalano, Jeffrey/0000-0001-9311-977X NR 36 TC 28 Z9 29 U1 3 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD AUG 1 PY 2003 VL 320 IS 3 BP 231 EP 244 DI 10.1016/S0022-3115(03)00186-7 PG 14 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 709CX UT WOS:000184608100007 ER PT J AU Siantar, CLH DeNardo, GL DeNardo, SJ AF Siantar, CLH DeNardo, GL DeNardo, SJ TI Impact of nodal regression on radiation dose for lymphoma patients after radioimmunotherapy SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article DE radiation dose; lymphoma; radioimmunotherapy; nodal regression; antibody ID NON-HODGKINS-LYMPHOMA; I-131 LYM-1 ANTIBODY; FRACTIONATED RADIOIMMUNOTHERAPY; MONOCLONAL-ANTIBODIES; DOSIMETRY; THERAPY; EFFICACY; TUMORS AB Radioimmunotherapy for non-Hodgkin's lymphoma often results in surprisingly high response rates compared with those expected from estimated absorbed radiation doses. Several factors, including radiobiologic response, selective targeting, and heterogeneous absorbed radiation within the lymphoma, are likely to contribute to the lack of a dose-response relationship. This article investigates the impact of nodal regression on absorbed radiation dose and applies a correction factor to account for its effect. Methods: The radioactivity in and regression of 37 superficial lymph nodes were measured in 7 non-Hodgkin's lymphoma patients treated with 775-3,450 MBq/m(2) of I-131-Lym-1 monoclonal antibody. Nodal dimensions were measured with calipers and radioactivity was quantitated using gamma-camera imaging on multiple days after I-131-Lym-1 injection. Both nodal regression and radioactivity were fit with mono-exponential functions. Formulas were developed to account for simultaneous change in nodal mass and radioactivity. All lymph nodes with size and radioactivity measurements, and exponential-fit coefficients of determination of >0.8, were included in the analysis. Results: A 3 orders-of-magnitude node-to-node variation in initial radiopharmaceutical concentration (MBq/g) was observed, with the highest concentrations in the smallest nodes. Reduction in radioactivity as a function of time (biologic half-life) varied by about a factor of 2. In contrast, the rate of nodal regression varied by orders of magnitude, from a 14-h half-time to no regression at all. Five nodes regressed with a half-time that was shorter than their observed effective radiopharmaceutical half-life. Accounting for the effect of nodal regression resulted in dose corrections ranging from 1 (no correction) to a factor of >10, with 70% of nodes requiring a correction factor of at least 20% and >50% of nodes requiring a correction factor of >2. Corrected for nodal regression, 46% of nodes analyzed had absorbed radiation doses of >10 Gy and 32% had doses of >20 Gy. Conclusion: These results highlight the importance of accounting for change in mass, particularly tumor regression, when assessing absorbed radiation dose for tissues whose mass changes during the time the radiation dose is being absorbed. The increase in calculated absorbed dose when this change is considered provides better insight into the high nodal response rates observed in non-Hodgkin's lymphoma patients. C1 Lawrence Livermore Natl Lab, Glenn T Seaborg Inst, Livermore, CA 94550 USA. Univ Calif Davis, Med Ctr, Mol Canc Inst, Sect Radiodiag & Therapy, Sacramento, CA 95817 USA. RP Siantar, CLH (reprint author), Lawrence Livermore Natl Lab, Glenn T Seaborg Inst, POB 808, Livermore, CA 94550 USA. NR 26 TC 11 Z9 11 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD AUG PY 2003 VL 44 IS 8 BP 1322 EP 1329 PG 8 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 709XB UT WOS:000184650900023 ER PT J AU Loewen, EP Tokuhiro, AT AF Loewen, EP Tokuhiro, AT TI Status of research and development of the lead-alloy-cooled fast reactor SO JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY LA English DT Review DE nuclear reactors; lead-cooled reactors; actinide-burning ID VAPOR EXPLOSIONS; NUCLEAR-POWER; BISMUTH; TRANSIENT; CORROSION; BEHAVIOR; COOLANT; SYSTEMS; DESIGN; OXYGEN AB The U.S. Department of Energy is leading an international initiative to develop the Generation IV Nuclear Reactor. The vast majority of the nation's 104 reactors are type Generation II; Generation III designs (i.e., Advanced Boiling Water Reactor) and have only been built overseas (Korea, Japan). The Generation IV reactor concepts must meet the following criteria: (1) economic competitiveness, (2) inherent safety, (3) minimization of waste, (4) nonproliferation enhancement, and (5) provide social benefit (electricity, "hydricity"). One of the concepts under evaluation is the lead-cooled (Pb) or lead-alloy-cooled (primarily Pb-Bi) fast reactor. Lead/Lead-bismuth reactor cooling offers enhanced safety and reliability in contrast to other liquid metals through its properties, these being chemical inertness with air and water, high atomic number, low vapor pressure at operating temperatures, and high boiling temperature. The only significant drawback is "corrosiveness," or incompatibility with fuel cladding and structural materials. The review presents the state of development not only of lead/reactor material compatibility research, but also of the extent of international activities toward realization of a Pb/Pb-Bi-cooled fast reactor. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Univ Missouri, Nucl Engn Dept, Rolla, MO 65409 USA. RP Loewen, EP (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 105 TC 16 Z9 16 U1 0 U2 27 PU ATOMIC ENERGY SOC JAPAN PI TOKYO PA 1-1-13 SHIMBASHI MINATO-KU, TOKYO, 105, JAPAN SN 0022-3131 J9 J NUCL SCI TECHNOL JI J. Nucl. Sci. Technol. PD AUG PY 2003 VL 40 IS 8 BP 614 EP 627 DI 10.3327/jnst.40.614 PG 14 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 729UY UT WOS:000185794500007 ER PT J AU Yamataka, H Aida, M Dupuis, M AF Yamataka, H Aida, M Dupuis, M TI Ab initio molecular dynamics studies on substitution vs electron transfer reactions of substituted ketyl radical anions with chloroalkanes: how do the two products form in a borderline mechanism? SO JOURNAL OF PHYSICAL ORGANIC CHEMISTRY LA English DT Article DE direct molecular dynamics simulation; MO calculations; borderline mechanism; electron transfer; S(N)2; transition state ID ZERO-POINT ENERGY; ALIPHATIC NUCLEOPHILIC-SUBSTITUTION; CLASSICAL TRAJECTORY SIMULATIONS; TRANSFER TRANSITION-STATE; ALKYL-HALIDES; ORGANIC-REACTIVITY; STERIC HINDRANCE; METHYL-CHLORIDE; MD SIMULATIONS; MODEL AB We present a qualitative analysis, based on ab initio molecular dynamics (MD) calculations, of the S(N)2/ ET mechanistic spectrum for three reactions: (1) HC(CN)=O.- + CH3Cl, (2) HC(CN)=O.- + (CH3)(2)CHCl and (3) H2C=O.-+CH3Cl, passing through their S(N)2-like transition states. Finite temperature (298K) direct MD simulations indicate that the trajectories for reaction (1) appear to have a propensity towards S(N)2 products, the propensity for trajectories for reaction (2) seems to be towards ET products, whereas trajectories for reaction (3) appear to show no particular propensity towards either ET or SN2 products. The mechanistic diversity is consistent with the electron-donating ability of the ketyl species and steric bulkiness of chloroalkanes. We find that the trajectories have characteristics that reflect strongly the types of process [S(N)2 trajectories in reactions (1) and (3) vs. ET trajectories in reactions (2) and (3)]. Trajectories that lead to SN2 products are simple with C-C bond formation and C-Cl bond breaking essentially completed within 50 fs. By contrast, trajectories leading to ET products are more complex with a sudden electron reorganization taking place within 15-30 fs and the major bonding changes and electron and spin reorganizations completed after 250 fs. Copyright (C) 2003 John Wiley Sons, Ltd. C1 Osaka Univ, Inst Sci & Ind Res, Osaka 5670047, Japan. Hiroshima Univ, Fac Sci, Higashihiroshima 7398526, Japan. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Yamataka, H (reprint author), Osaka Univ, Inst Sci & Ind Res, Osaka 5670047, Japan. RI Aida, Misako/D-1670-2010 OI Aida, Misako/0000-0001-8788-1071 NR 44 TC 19 Z9 19 U1 1 U2 3 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0894-3230 J9 J PHYS ORG CHEM JI J. Phys. Org. Chem. PD AUG PY 2003 VL 16 IS 8 BP 475 EP 483 DI 10.1002/poc.610 PG 9 WC Chemistry, Organic; Chemistry, Physical SC Chemistry GA 716BR UT WOS:000185009400009 ER PT J AU Kayser, B AF Kayser, B TI Neutrino physics, superbeams and the neutrino factory SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB We summarize what has been learned about the neutrino mass spectrum and neutrino mixing, identify interesting open questions that can be answered by accelerator neutrino facilities of the future, and discuss the importance and physics of answering them. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Kayser, B (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 21 TC 1 Z9 1 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 EI 1361-6471 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1463 EP 1470 AR PII S0954-3899(03)61194-1 DI 10.1088/0954-3899/29/8/301 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600002 ER PT J AU Geer, S AF Geer, S TI Neutrino factories: physics potential SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL ID FLUX AB The physics potential of low-performance and high-performance neutrino factories is briefly reviewed. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Geer, S (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 16 TC 9 Z9 9 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1485 EP 1492 AR PII S0954-3899(03)59884-X DI 10.1088/0954-3899/29/8/304 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600005 ER PT J AU Zisman, MS AF Zisman, MS CA Neutrino Factory Muon Collider Col TI Review of north American neutrino factory R&D SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB We report here on the R&D programme of the U.S. Neutrino Factory and Muon Collider Collaboration. Our effort includes work on targetry, muon ionization cooling, simulation work and development of superconducting RF cavities. In addition, we are involved in the international effort towards a muon ionization cooling experiment (MICE). Recent activities in all these areas will be described. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Accelerator & Fus Res, Ctr Beam Phys, Berkeley, CA 94720 USA. RP Zisman, MS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Accelerator & Fus Res, Ctr Beam Phys, Berkeley, CA 94720 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1515 EP 1526 AR PII S0954-3899(03)60027-7 DI 10.1088/0954-3899/29/8/308 PG 12 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600009 ER PT J AU Palmer, RB AF Palmer, RB TI Ring coolers SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB The simulated performance of three different 6D muon cooling rings is presented. Two of these used solenoid focusing and one used quadrupoles. All three performed better than the linear cooling channel described in Study-2 (Ozaki S, Palmer R B, Zisman M S and Gallardo J C 2001 BNL-52623). The best example increased the 6D phase space density by a factor of 162, compared with the linear channel's factor of only 15. However, none of the simulations used fully realistic magnetic fields, and absorber and radio frequency (RF) cavity windows were not included. Injection/extraction is discussed. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Palmer, RB (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 11 TC 13 Z9 13 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1577 EP 1583 AR PII S0954-3899(03)60073-3 DI 10.1088/0954-3899/29/8/315 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600016 ER PT J AU Sessler, AM AF Sessler, AM TI Closing remarks at 4th NuFact '02 workshop, London, England, 6 July 2002 SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB A brief survey is given of actual R&D activities around the world. Following that, various conceptual developments significant to factories are reviewed. Then we turn to the costs of a factory. We discuss the present budgetary woes throughout the world and end with some closing remarks. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. RP Sessler, AM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Beam Phys, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1629 EP 1635 AR PII S0954-3899(03)61269-7 DI 10.1088/0954-3899/29/8/321 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600022 ER PT J AU Autin, B Fernow, RC Machida, S Harris, DA AF Autin, B Fernow, RC Machida, S Harris, DA TI NuFact02 machine working group summary SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB This is a summary of discussions that took place in the Machine Working Group at NuFact02. C1 CERN, CH-1211 Geneva 23, Switzerland. Brookhaven Natl Lab, Upton, NY 11973 USA. KEK, Tsukuba, Ibaraki, Japan. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Autin, B (reprint author), CERN, CH-1211 Geneva 23, Switzerland. NR 51 TC 10 Z9 10 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1637 EP 1647 AR PII S0954-3899(03)59897-8 DI 10.1088/0954-3899/29/8/322 PG 11 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600023 ER PT J AU Berg, JS Fernow, RC Palmer, RB AF Berg, JS Fernow, RC Palmer, RB TI RFOFO ring cooler SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB This note describes the design of an ionization cooling ring that uses an alternating polarity solenoid lattice. The ring is approximately 33 m in circumference and has 12 cells. Each cell has two opposing focusing solenoids placed either side of a hydrogen wedge absorber. The solenoid coils are located outside pillbox rf cavities. Bending is provided by tipping the solenoid coils. The simulated merit factor (approximate to the increase in six-dimensional phase-space density) is 81. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Berg, JS (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Berg, Joseph/E-8371-2014 OI Berg, Joseph/0000-0002-5955-6973 NR 2 TC 6 Z9 6 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1657 EP 1659 AR PII S0954-3899(03)60074-5 DI 10.1088/0954-3899/29/8/325 PG 3 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600026 ER PT J AU Li, DR Corlett, J Ladran, A MacGill, R Wallig, J Zisman, M Moretti, A Rowe, A Qian, ZB Wu, V Rimmer, RA Norem, J Summers, D Torun, Y AF Li, DR Corlett, J Ladran, A MacGill, R Wallig, J Zisman, M Moretti, A Rowe, A Qian, ZB Wu, V Rimmer, RA Norem, J Summers, D Torun, Y TI 805 MHz and 201 MHz RF cavity development for MUCOOL SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB A muon cooling channel calls for very high accelerating gradient RF structures to restore the energy lost by muons in the absorbers. The RF structures have to be operated in a strong magnetic field and thus the use of superconducting RF cavities is excluded. To achieve a high shunt impedance while maintaining a large enough aperture to accommodate a large transverse emittance muon beam, the cavity design adopted is a pillbox-like geometry with thin Be foils to terminate the electromagnetic field at the cavity iris. The possibility of using grids of thin-walled metallic tubes for the termination is also being explored. Many of the RF-related issues for muon cooling channels are being studied both theoretically and experimentally using an 805 MHz cavity that has a pillbox-like geometry with thin Be windows to terminate the cavity aperture. The design and performance of this cavity are reported here. High-power RF tests of the 805 MHz cavity are in progress at Lab G in Fermilab. The cavity has exceeded its design gradient of 30 MV m(-1), reaching 34 MV m(-1) without external magnetic field. No surface damage was observed at this gradient. The cavity is currently under conditioning at Lab G with an external magnetic field of 2.5 T. We also present here a 201 MHz cavity design for muon cooling channels. The proposed cavity design is also suitable for use in a proof-of-principle muon ionization cooling experiment. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Jefferson Lab, Newport News, VA 23606 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Mississippi, Oxford, MS 38677 USA. IIT, Chicago, IL 60616 USA. RP Li, DR (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. OI Torun, Yagmur/0000-0003-2336-6585 NR 4 TC 9 Z9 9 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1683 EP 1687 AR PII S0954-3899(03)60075-7 DI 10.1088/0954-3899/29/8/330 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600031 ER PT J AU Cummings, MAC Allspach, D Bandura, L Black, EL Cassel, KW Dyshkant, A Errede, D Geer, S Greenwood, J Haney, M Hedin, D Ishimoto, S Johnstone, CJ Kaplan, DM Kubik, D Kuno, Y Lau, W Majewski, S Norem, J Norris, B Popovic, M Reep, M Summers, D Yoshimura, K AF Cummings, MAC Allspach, D Bandura, L Black, EL Cassel, KW Dyshkant, A Errede, D Geer, S Greenwood, J Haney, M Hedin, D Ishimoto, S Johnstone, CJ Kaplan, DM Kubik, D Kuno, Y Lau, W Majewski, S Norem, J Norris, B Popovic, M Reep, M Summers, D Yoshimura, K TI Current LH2-absorber R&D in MuCool SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB The MuCool hydrogen-absorber R&D program is summarized. Prototype absorbers featuring thin aluminum windows and 'flow-through' or 'convection' cooling are under development for eventual power-handling tests in a proton beam and a cooling demonstration in a muon beam. Testing these prototypes and their components involves application of novel techniques. C1 No Illinois Univ, De Kalb, IL 60115 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. IIT, Chicago, IL 60616 USA. Univ Illinois, Urbana, IL 61801 USA. KEK, Tsukuba, Ibaraki 305, Japan. Osaka Univ, Osaka 567, Japan. Univ Oxford, Oxford OX1 3NP, England. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Mississippi, University, MS 38677 USA. RP Cummings, MAC (reprint author), No Illinois Univ, De Kalb, IL 60115 USA. OI Cassel, Kevin/0000-0003-0981-496X NR 3 TC 3 Z9 3 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1689 EP 1692 AR PII S09524-3899(03)61519-7 DI 10.1088/0954-3899/29/8/331 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600032 ER PT J AU Norem, J Li, D Bross, A Moretti, A Qian, Z Torun, Y McKigney, E AF Norem, J Li, D Bross, A Moretti, A Qian, Z Torun, Y McKigney, E TI RF induced backgrounds in MICE SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL C1 Argonne Natl Lab, HEP Div, Argonne, IL 60439 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. IIT, Chicago, IL 60616 USA. Univ London Imperial Coll Sci Technol & Med, London, England. RP Norem, J (reprint author), Argonne Natl Lab, HEP Div, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Torun, Yagmur/0000-0003-2336-6585 NR 3 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1697 EP 1700 AR PII S0954-3899(03)60342-7 DI 10.1088/0954-3899/29/8/333 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600034 ER PT J AU Bogacz, SA AF Bogacz, SA TI Beam dynamics of muon acceleration for neutrino factory SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB A conceptual design of a muon acceleration scheme based on recirculating superconducting linacs is proposed. In the presented scenario, acceleration starts after ionization cooling at 245 MeV/c and proceeds to 20 GeV, where the beam is injected into a neutrino factory storage ring. The key technical issues are addressed; such as: the choice of acceleration technology (superconducting versus normal conducting) and the choice of RF frequency and finally, implementation of the overall acceleration scheme: capture, acceleration, transport and preservation of large phase space of fast decaying species. Beam transport issues for large-momentum-spread beams are accommodated by appropriate lattice design choices. The proposed arc optics is further optimized with a sextupole correction to suppress chromatic effects contributing to emittance dilution. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Bogacz, SA (reprint author), Jefferson Lab, Newport News, VA 23606 USA. NR 3 TC 6 Z9 6 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1723 EP 1726 AR PII S0954-3899(03)60069-1 DI 10.1088/0954-3899/29/8/338 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600039 ER PT J AU Summers, DJ Berg, JS Garren, AA Palmer, RB AF Summers, DJ Berg, JS Garren, AA Palmer, RB TI Muon acceleration with a very fast ramping synchrotron for a neutrino factory SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL ID SOLAR NEUTRINOS; COLLIDER; PHYSICS; OSCILLATION; STORAGE AB A 4600 Hz fast ramping synchrotron is explored as an economical way of accelerating muons from 4 to 20 GeV/c for a neutrino factory. Eddy current losses are minimized by the low machine duty cycle plus thin grain oriented silicon steel laminations and thin copper wires. Combined function magnets with high gradients alternating within single magnets form the lattice we describe. Muon survival is 83%. C1 Univ Mississippi, Dept Phys, Oxford, MS 38677 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. RP Summers, DJ (reprint author), Univ Mississippi, Dept Phys, Oxford, MS 38677 USA. RI Berg, Joseph/E-8371-2014 OI Berg, Joseph/0000-0002-5955-6973 NR 56 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1727 EP 1733 AR PII S0954-3899(03)60288-4 DI 10.1088/0954-3899/29/8/339 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600040 ER PT J AU Weng, WT Beavis, D Brennan, M Diwan, M Fernow, R Gallardo, J Kahn, S Kirk, H Lowenstein, D Marciano, W Marneris, I Morse, W Parsa, Z Palmer, R Raparia, D Roser, T Ruggiero, A Sandberg, J Samios, N Semertzidis, Y Simos, N Tsoupas, N Viren, B AF Weng, WT Beavis, D Brennan, M Diwan, M Fernow, R Gallardo, J Kahn, S Kirk, H Lowenstein, D Marciano, W Marneris, I Morse, W Parsa, Z Palmer, R Raparia, D Roser, T Ruggiero, A Sandberg, J Samios, N Semertzidis, Y Simos, N Tsoupas, N Viren, B TI The neutrino superbeam from the AGS SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Weng, WT (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Semertzidis, Yannis K./N-1002-2013; OI Gallardo, Juan C/0000-0002-5191-3067 NR 2 TC 3 Z9 3 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1735 EP 1738 AR PII S0954-3899(03)59865-6 DI 10.1088/0954-3899/29/8/340 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600041 ER PT J AU Autin, B Harris, DA King, SF McFarland, KS Yasuda, O AF Autin, B Harris, DA King, SF McFarland, KS Yasuda, O TI Summary of Working Group 2 SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL ID NEUTRINOS; PARTICLES; PHYSICS; LSND AB Issues on the physics of, beamlines for, and detectors of neutrino oscillation discussed in Working Group 2 at Nufact'02 are summarized. C1 CERN, Geneva, Switzerland. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Southampton, Dept Phys & Astron, Southampton SO17 1BJ, Hants, England. Tokyo Metropolitan Univ, Dept Phys, Tokyo 1920397, Japan. RP Autin, B (reprint author), CERN, Geneva, Switzerland. EM dhanis@fnal.gov NR 29 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 EI 1361-6471 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1743 EP 1755 AR PII S0954-3899(03)60179-9 DI 10.1088/0954-3899/29/8/342 PG 13 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600043 ER PT J AU Kahn, S AF Kahn, S TI Neutrino super-beam facility for a long baseline experiment from BNL to Homestake SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB An upgrade to the BNL alternate gradient synchrotron (AGS) could produce a very intense proton source at a relatively low cost. Such a proton beam could be used to generate a conventional neutrino beam with a significant flux at large distances from the laboratory. This provides the possibility of a very long baseline neutrino experiment at the Homestake mine. The construction of this facility would allow a programme of experiments to study many of the aspects of neutrino oscillations including CP violation. This study examines a 1 MW proton source at BNL and a 1 megaton detector positioned at the Homestake mine as the ultimate goal of a staged programme to study neutrino oscillations. C1 Brookhaven Natl Lab, Upton, NY 11725 USA. RP Kahn, S (reprint author), Brookhaven Natl Lab, Upton, NY 11725 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1763 EP 1766 AR PII S0954-3899(03)59885-1 DI 10.1088/0954-3899/29/8/344 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600045 ER PT J AU Autin, B Benedikt, M Grieser, M Hancock, S Haseroth, H Jansson, A Koster, U Lindroos, M Russenschuck, S Wenander, F AF Autin, B Benedikt, M Grieser, M Hancock, S Haseroth, H Jansson, A Koster, U Lindroos, M Russenschuck, S Wenander, F TI The acceleration and storage of radioactive ions for a neutrino factory SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL ID BEAM AB The term beta-beam has been coined for the production of a pure beam of electron neutrinos or their antiparticles through the decay of radioactive ions circulating in a storage ring. This concept requires radioactive ions to be accelerated to a Lorentz gamma of 150 for He-6 and 60 for Ne-18. The neutrino source itself consists of a storage ring for this energy range, with long straight sections in line with the experiment(s). Such a decay ring does not exist at CERN today, nor does a high-intensity proton source for the production of the radioactive ions. Nevertheless, the existing CERN accelerator infrastructure could be used as this would still represent an important saving for a beta-beam facility. This paper outlines the first study, while some of the more speculative ideas will need further investigations. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. CERN, CH-1211 Geneva, Switzerland. RP Autin, B (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 24 TC 51 Z9 51 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1785 EP 1795 AR PII S0954-3899(03)61246-6 DI 10.1088/0954-3899/29/8/349 PG 11 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600050 ER PT J AU Bernstein, RH AF Bernstein, RH TI Standard model explanations for the NuTeV electroweak measurements SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB The NuTeV Collaboration has measured the electroweak parameters sin(2) theta(W) and rho in neutrino-nucleon deep-inelastic scattering using a sign-selected beam. The nearly pure nu or nu beams that result provide many of the cancellations of systematics associated with the Paschos-Wolfenstein relation. The extracted result for sin(2) theta(W) (on-shell) = 1 - M-W(2)/M-Z(2) is three standard deviations from prediction. We discuss standard model explanations for the puzzle. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Bernstein, RH (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. OI Bernstein, Robert/0000-0002-7610-950X NR 15 TC 3 Z9 3 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1919 EP 1923 AR PII S0954-3899(03)60267-7 DI 10.1088/0954-3899/29/8/373 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600074 ER PT J AU Morfin, JG AF Morfin, JG TI A fine-grained detector to study nuclear effects in a NuMI neutrino scattering experiment SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB The NuMI facility at Fermilab will provide an extremely intense beam of neutrinos making it the ideal location for high statistics (anti)neutrino-nucleon/nucleas experiments. With such intensities, a fine-grained, solid scintillator detector becomes practical. The ability of such a detector to examine so-far unstudied nuclear effects in neutrino scattering will be addressed. Recent theoretical work suggests that such effects will be considerably different from those measured with electron and muon beams. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Morfin, JG (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 8 TC 5 Z9 5 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1935 EP 1942 AR PII S0954-3899(03)61509-4 DI 10.1088/0954-3899/29/8/375 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600076 ER PT J AU Bernstein, RH AF Bernstein, RH TI Charged-current disappearance measurements in the NuMI off-axis beam SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 4th International Workshop on Neutrino Factories (NuFact02) CY JUL 01-06, 2002 CL IMPERIAL COLL, LONDON, ENGLAND HO IMPERIAL COLL AB This paper studies the potential of combining charged-current disappearance measurements of v(mu) --> v(tau) from MINOS and an off-axis beam. I find that the error on Deltam(2) from a 100 kt-year off-axis measurement is a few per cent of itself. Further, I find little improvement to an off-axis measurement by combining it with MINOS. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Bernstein, RH (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. OI Bernstein, Robert/0000-0002-7610-950X NR 7 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD AUG PY 2003 VL 29 IS 8 BP 1997 EP 2000 AR PII S0954-3899(03)61552-5 DI 10.1088/0954-3899/29/8/389 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 714YM UT WOS:000184942600090 ER PT J AU Wahl, JH Riechers, DM Vucelick, ME Wright, BW AF Wahl, JH Riechers, DM Vucelick, ME Wright, BW TI A portable multi-dimensional gas chromatographic system for field applications SO JOURNAL OF SEPARATION SCIENCE LA English DT Article DE multi-dimensional gas chromatography; field portable; rapid gas chromatography ID GC X GC; MASS-SPECTROMETRY; MODULATOR; HYDROCARBONS; GASOLINE; SAMPLES AB We have constructed and tested a multi-dimensional gas chromatographic system that can be utilized for field portable applications. The chromatographic system is capable of one-dimensional separations and multi-dimensional gas chromatographic (MDGC) separations in a single compact package. Three different general multidimensional separation approaches are possible: column switching; traditional heart-cutting; and comprehensive analyses. The MDGC system utilizes a simple 10-port valving approach to accomplish these separations to a single point detector. Because of this valving scheme no hardware change is required to switch between the heart-cut and the comprehensive separation modes, only a software methodology change is required. An additional advantage of this valving approach is that 100% of the first-dimensional effluent is sampled to the second dimension for separation. The system is capable of rapid column heating (room temperature to 250degreesC in approximately 10 s) and rapid column cooling (250degreesC to room temperature within approximately 30 s). Preliminary results for heart-cut and comprehensive separations that target five compounds against high concentration levels of complex background are illustrated. C1 Natl Secur Directorate, Pacific NW Natl Lab, Richland, WA 99352 USA. RP Wahl, JH (reprint author), Natl Secur Directorate, Pacific NW Natl Lab, POB 999 MSIN P8-50, Richland, WA 99352 USA. NR 26 TC 8 Z9 8 U1 1 U2 2 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 1615-9314 J9 J SEP SCI JI J. Sep. Sci. PD AUG PY 2003 VL 26 IS 12-13 BP 1083 EP 1090 DI 10.1002/jssc.200301504 PG 8 WC Chemistry, Analytical SC Chemistry GA 718TW UT WOS:000185163400001 ER PT J AU Walker, A Renne, D Bilo, S Kutscher, C Burch, J Balcomb, D Judkoff, R Warner, C AF Walker, A Renne, D Bilo, S Kutscher, C Burch, J Balcomb, D Judkoff, R Warner, C TI Advances in solar buildings SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID SYSTEMS; PERFORMANCE AB In the autumn of 2002, 14 universities built solar houses on the National Mall in Washington, DC, in a student competition-the Solar Decathlon-demonstrating that homes call derive all the energy they need from the sun and celebrating advances in solar buildings. This paper describes recent progress in solar building technology that expands the designer's palette and holds the potential to radically improve building energy performance. The discussion includes market conditions and solar resource data; design integration and modeling; window technology, daylighting, passive solar heating; solar water heating; solar ventilation air preheating; building-integrated photovoltaics; and solar cooling. The Solar Decathlon competition highlighted ways in which these strategies are integrated in successful solar buildings. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. US DOE, Solar Energy Technol Program, Washington, DC 20585 USA. Imaginit Inc, Golden, CO 80401 USA. RP Walker, A (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 53 TC 7 Z9 7 U1 1 U2 11 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD AUG PY 2003 VL 125 IS 3 BP 236 EP 244 DI 10.1115/1.1592537 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 714HJ UT WOS:000184907300002 ER PT J AU Katipamula, S Brambley, MR Luskay, L AF Katipamula, S Brambley, MR Luskay, L TI Automated proactive techniques for commissioning air-handling units SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB Lack of or improper commissioning, the inability of the building operators to grasp the complexity controls, and lack of proper maintenance lead to inefficient operations and reduced lifetimes of equipment. If regularly scheduled manual maintenance or recommissioning practices are adopted, they can be expensive and time consuming. Automated proactive commissioning and diagnostic technologies applied to parts of the commissioning process address two of the main barriers to commissioning cost and schedules. Automated proactive commissioning and diagnostic tools can reduce both the cost and time associated with commissioning, as well as enhance the persistence of commissioning fixes. In the long run, automation even offers the potential for automatically correcting problems by reconfiguring controls or changing control algorithms dynamically. This paper discusses procedures and processes that can be used to automate and continuously commission the economizer operation and outdoor-air ventilation systems of an air-handling unit. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Portland Energy Conservat Inc, Portland, OR 97201 USA. RP Katipamula, S (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 9 TC 5 Z9 5 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD AUG PY 2003 VL 125 IS 3 BP 282 EP 291 DI 10.1115/1.1591800 PG 10 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 714HJ UT WOS:000184907300008 ER PT J AU Rai, D Hess, NJ Xia, YX Rao, LF Cho, HM Moore, RC Van Loon, LR AF Rai, D Hess, NJ Xia, YX Rao, LF Cho, HM Moore, RC Van Loon, LR TI Comprehensive thermodynamic model applicable to highly acidic to basic conditions for isosaccharinate reactions with Ca(II) and Np(IV) SO JOURNAL OF SOLUTION CHEMISTRY LA English DT Article DE isosaccharinate; isosaccharinic acid; thermodynamics; ion-interaction parameters; solubility; NpO2(am); solvent extraction; equilibrium constants; alpha-D-isosaccharinic acid; alpha-D-isosaccharino-1,4-lactone ID RADIOACTIVE-WASTE REPOSITORY; ALKALINE CONDITIONS; HYDROUS OXIDE; CALCIUM ISOSACCHARINATE; DEGRADATION PRODUCTS; SOLUBILITY; TH(IV); CELLULOSE; EU(III); IDENTIFICATION AB Isosaccharinate (ISA(-)), a degradation product of cellulose codisposed in low-level nuclear wastes, is expected to be one of the dominant complexing ligands for radionuclides, especially tetravalent actinides. This paper presents a comprehensive thermodynamic model for isosaccharinate reactions with Ca(II) and Np(IV). The model is valid for a wide range of pH values (similar to2-14), ISA(-) concentrations (ranging up to 0.1 m), and ionic strengths (ranging up to 6.54 m), and is based on (1) NMR investigations of HISA(aq) (alpha-D-isosaccharinic acid) and ISL(aq) [dehydration product of HISA(aq)], and the solubility of Ca(ISA)2(c) as a function of pH and concentrations of Ca and ISA(-); (2) NpO2(am) solubility in a wide range of pH values (similar to2-14) and total ISA concentrations of 0.0016 and 0.008 m and at fixed pH values of approximately 5 and 12 with total ISA concentrations ranging from 0.0001 to 0.1 m; and (3) solvent extraction of Np-ISA solutions, containing fixed NaClO4 concentrations ranging from 0.103 to 6.54 m and at fixed pC(H+) values ranging from 1.5 to 1.9, with dibenzoylmethane. Pitzer's ion-interaction approach was used to interpret the data. The different aqueous species required to explain these data included HISA(aq), ISL(aq), Ca(ISA)(+), Np(OH)(3)(ISA)(aq), Np(OH)(3)(ISA)(2)(-), Np(OH)(4)(ISA)(-), and Np(OH)(4)(ISA)(2)(2-). The values of equilibrium constants for reactions involving these species and determined from these data provided close agreements between the observed and predicted concentrations in all of the systems investigated in this study and those reported previously. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Berkeley Natl Lab, Berkeley, CA USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Paul Scherrer Inst, Villigen, Switzerland. RP Rai, D (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Van Loon, Luc/B-1708-2012; OI Van Loon, Luc/0000-0002-5844-0784; Hess, Nancy/0000-0002-8930-9500 NR 34 TC 18 Z9 18 U1 2 U2 11 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0095-9782 J9 J SOLUTION CHEM JI J. Solut. Chem. PD AUG PY 2003 VL 32 IS 8 BP 665 EP 689 DI 10.1023/B:JOSL.0000002988.99769.cb PG 25 WC Chemistry, Physical SC Chemistry GA 742MD UT WOS:000186520700001 ER PT J AU Cho, H Rai, D Hess, NJ Xia, YX Rao, LF AF Cho, H Rai, D Hess, NJ Xia, YX Rao, LF TI Acidity and structure of isosaccharinate in aqueous solution: A nuclear magnetic resonance study SO JOURNAL OF SOLUTION CHEMISTRY LA English DT Article DE isosaccharinate; "alpha"-D-isosaccharinate acid; "alpha"-D-isosaccharinate1,4-lactone; nuclear magnetic resonance spectroscopy; equilibrium constants; acid dissociation constants; monosaccharide structure ID CELLULOSE DEGRADATION PRODUCT; RADIOACTIVE-WASTE REPOSITORY; ALKALINE-DEGRADATION; CALCIUM ISOSACCHARINATE; POLARIZATION TRANSFER; SOLUBILITY; CEMENT; ACTINIDES; SORPTION AB Dilute aqueous solutions of the calcium and sodium salts of "alpha"-D-isosaccharinate (ISA) have been analyzed by C-13 and H-1 NMR spectroscopy. The positions of the six C-13 ISA NMR lines show a pH dependence that can be used to infer that the most acidic proton is the one associated with the carboxylate group, with an average log k(0) of -3.27 for the reaction H(ISA)reversible arrow H+ + ISA(-) in solutions made with the sodium salt. In acidic solutions (pH<4), NMR signals were found that could be assigned to "α"-D-isosaccharinate-1,4-lactone (ISL), formed from the dehydration of H(ISA). The pH dependence of the H(ISA) C-13 line positions, furthermore, reveals that the deprotonated H(ISA) at neutral to high pH assumes a conformation with the carboxylate anion hydrogen-bonded to the secondary alcohol and the cation (Na+ or Ca2+) interacting with the tertiary alcohol. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Cho, H (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. OI Hess, Nancy/0000-0002-8930-9500 NR 31 TC 16 Z9 16 U1 1 U2 9 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0095-9782 J9 J SOLUTION CHEM JI J. Solut. Chem. PD AUG PY 2003 VL 32 IS 8 BP 691 EP 702 DI 10.1023/B:JOSL.0000002989.03341.13 PG 12 WC Chemistry, Physical SC Chemistry GA 742MD UT WOS:000186520700002 ER PT J AU Heyliger, P Ledbetter, H Kim, S AF Heyliger, P Ledbetter, H Kim, S TI Elastic constants of natural quartz SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID CRYSTALS; SPECTROSCOPY AB The elastic constants of a natural-quartz sphere using resonance-ultrasound spectroscopy (RUS) are measured. The measurements of the near-traction-free vibrational frequencies of the sphere are matched with the predicted frequencies from the dynamic theory of elasticity, with optimized estimates for the elastic constants driving the differences between these sets of frequencies to a minimal value. The present computational model, although based on earlier approaches, is the first application of RUS to trigonal-symmetry spheres. Quartz shows six independent elastic constants, and our estimates of these constants are close to those computed by other means. Except for C-14, after a 1% mass-density correction, natural quartz and cultured quartz show the same elastic constants. Natural quartz shows higher internal frictions. (C) 2003 Acoustical Society of America. C1 Colorado State Univ, Dept Civil Engn, Ft Collins, CO 80523 USA. Los Alamos Natl Lab E536, Los Alamos, NM 87545 USA. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Boulder, CO 80305 USA. RP Heyliger, P (reprint author), Colorado State Univ, Dept Civil Engn, Ft Collins, CO 80523 USA. NR 27 TC 44 Z9 44 U1 1 U2 12 PU ACOUSTICAL SOC AMER AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD AUG PY 2003 VL 114 IS 2 BP 644 EP 650 DI 10.1121/1.1593063 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 709RE UT WOS:000184637500009 PM 12942948 ER PT J AU Ott, WR Klepeis, NE Switzer, P AF Ott, WR Klepeis, NE Switzer, P TI Analytical solutions to compartmental indoor air quality models with application to environmental tobacco smoke concentrations measured in a house SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID EXPOSURE; RATES; PARTICLES; FLOW AB This paper derives the analytical solutions to multicompartment indoor air quality models for predicting indoor air pollutant concentrations in the home and evaluates the solutions using experimental measurements in the rooms of a single-story residence. The model uses Laplace transform methods to solve the mass balance equations for two interconnected compartments, obtaining analytical solutions that can be applied without a computer. Environmental tobacco smoke (ETS) sources such as the cigarette typically emit pollutants for relatively short times (7-11 min) and are represented mathematically by a "rectangular" source emission time function, or approximated by a short-duration source called an "impulse" time function. Other time-varying indoor sources also can be represented by Laplace transforms. The two-compartment model is more complicated than the single-compartment model and has more parameters, including the cigarette or combustion source emission rate as a function of time, room volumes, compartmental air change rates, and interzonal air flow factors expressed as dimensionless ratios. This paper provides analytical solutions for the impulse, step (Heaviside), and rectangular source emission time functions. It evaluates the indoor model in an unoccupied two-bedroom home using cigars and cigarettes as sources with continuous measurements of carbon monoxide (CO), respirable suspended particles (RSP), and particulate polycyclic aromatic hydrocarbons (PPAH). Fine particle mass concentrations (RSP or PM3.5) are measured using real-time monitors. In our experiments, simultaneous measurements of concentrations at three heights in a bedroom confirm an important assumption of the model-spatial uniformity of mixing. The parameter values of the two-compartment model were obtained using a "grid search" optimization method, and the predicted solutions agreed well with the measured concentration time series in the rooms of the home. The door and window positions in each room had considerable effect on the pollutant concentrations observed in the home. Because of the small volumes and low air change rates of most homes, indoor pollutant concentrations from smoking activity in a home can be very high and can persist at measurable levels indoors for many hours. C1 Stanford Univ, Dept Stat, Stanford, CA 94305 USA. Stanford Univ, Dept Civil & Environm Engn, Stanford, CA 94305 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Indoor Environm Dept, Berkeley, CA 94720 USA. Stanford Univ, Dept Stat, Stanford, CA 94305 USA. RP Ott, WR (reprint author), Stanford Univ, Dept Stat, Sequoia Hall,Room 202, Stanford, CA 94305 USA. OI Klepeis, Neil/0000-0002-6934-3242 NR 36 TC 27 Z9 29 U1 3 U2 12 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 AUG PY 2003 VL 53 IS 8 BP 918 EP 936 PG 19 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 708EV UT WOS:000184554900002 PM 12943312 ER PT J AU Tortorelli, PF More, KL AF Tortorelli, PF More, KL TI Effects of high water-vapor pressure on oxidation of silicon carbide at 1200 degrees C SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Symposium on Water Vapor Effects on Oxidation of High-Temperature Materials held at the 131st Annual Meeting of the Minerals-Metals-and-Materials-Society CY FEB 18-20, 2002 CL SEATTLE, WASHINGTON SP Minerals, Met & Mat Soc ID SIO2 SCALE VOLATILITY; COMBUSTION CONDITIONS; WET OXYGEN; RECESSION; KINETICS; ENVIRONMENTS; CERAMICS; NITRIDE; MODEL AB The oxidation of SiC at 1200degreesC in a slowly flowing gas mixture of either air or air + 15 vol% H2O at 10 atm (1 MPa) was studied for extended times to examine the effects of elevated water-vapor pressure on oxidation rates and microstructural development. At a water-vapor pressure of 1.5 atm (150 kPa), distinct SiO2 scale structures were observed on the SiC; thick, porous, nonprotective cristobalite scales formed above a thin, nearly dense vitreous SiO2 layer, which remained constant in thickness with time as the crystalline SiO2 continued to grow. The pore morphology of the cristobalite layer differed depending on the type of SiC on which it was grown. The crystallization and growth rates of the cristobalite layer were significantly accelerated in the presence of the high water-vapor pressure and resulted in rapid rates of SiC surface recession that were on the order of what is observed when SiO2 volatility is rate controlling at high gas-flow velocities (30 m/s). The recession process can be described by a paralinear kinetic model controlled by the conversion of dense vitreous SiO2 to porous, nonprotective SiO2. RP Tortorelli, PF (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RI Tortorelli, Peter/E-2433-2011; More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 21 TC 47 Z9 49 U1 1 U2 15 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 2003 VL 86 IS 8 BP 1249 EP 1255 PG 7 WC Materials Science, Ceramics SC Materials Science GA 713YN UT WOS:000184885700003 ER PT J AU Opila, EJ Robinson, RC Fox, DS Wenglarz, RA Ferber, MK AF Opila, EJ Robinson, RC Fox, DS Wenglarz, RA Ferber, MK TI Additive effects onSi(3)N(4) oxidation/volatilization in water vapor SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Symposium on Water Vapor Effects on Oxidation of High-Temperature Materials held at the 131st Annual Meeting of the Minerals-Metals-and-Materials-Society CY FEB 18-20, 2002 CL SEATTLE, WASHINGTON SP Minerals, Met & Mat Soc ID SIO2 SCALE VOLATILITY; PRESSED SILICON-NITRIDE; COMBUSTION CONDITIONS; OXIDATION; RECESSION; KINETICS; CARBIDE; MODEL AB Two commercially available additive-containing silicon nitride materials were exposed in four environments which ranged in severity from dry oxygen at 1 atm pressure, and low gas velocity, to an actual turbine engine. Oxidation and volatilization kinetics were monitored at temperatures ranging from 1066degrees to 1400degreesC. The main purpose of this paper is to examine the surface oxide morphology resulting from the exposures. It was found that the material surface was enriched in rare-earth silicate phases in combustion environments when compared with the oxides formed on materials exposed in dry oxygen. However, the in situ formation of rare-earth disilicate phases offered little additional protection from the volatilization of silica observed in combustion environments. It was concluded that externally applied environmental barrier coatings are needed to protect additive-containing silicon nitride materials from volatilization reactions in combustion environments. C1 Cleveland State Univ, Cleveland, OH 44115 USA. QSS Grp Inc, Cleveland, OH 44135 USA. S Carolina Inst Energy Studies, Clemson, SC 29634 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. NR 28 TC 38 Z9 38 U1 1 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 2003 VL 86 IS 8 BP 1262 EP 1271 PG 10 WC Materials Science, Ceramics SC Materials Science GA 713YN UT WOS:000184885700005 ER PT J AU More, KL Tortorelli, PF Walker, LR Miriyala, N Price, JR van Roode, M AF More, KL Tortorelli, PF Walker, LR Miriyala, N Price, JR van Roode, M TI High-temperature stability of SiC-based composites in high-water-vapor-pressure environments SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Symposium on Water Vapor Effects on Oxidation of High-Temperature Materials held at the 131st Annual Meeting of the Minerals-Metals-and-Materials-Society CY FEB 18-20, 2002 CL SEATTLE, WASHINGTON SP Minerals, Met & Mat Soc ID CERAMIC-MATRIX COMPOSITES; SIO2 SCALE VOLATILITY; SILICON-CARBIDE; COMBUSTION CONDITIONS; BORON-NITRIDE; OXIDATION; RECESSION; FIBER; OXYGEN; MODEL AB Microstructural characterization of boron-containing SiC-reinforced SiC composites exposed at high temperature in high-water-vapor-pressure environments was used to determine surface recession rates and to understand the controlling degradation processes under these conditions. Results showed that composite degradation was controlled by a series of reactions involving the formation of silica, boria, borosilicate glass, and gaseous products. Comparison of results (from characterization of composites exposed at 1200degreesC and 1.5 atm of 11,0 in a laboratory furnace and in the combustion zone of a gas turbine) showed that these reactions were common to both exposure conditions and, consequently, there was little effect of gas velocity on degradation rates of boron-containing SiC/SiC composite materials. C1 Solar Turbines Inc, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Tortorelli, Peter/E-2433-2011; More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 26 TC 32 Z9 32 U1 0 U2 14 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 2003 VL 86 IS 8 BP 1272 EP 1281 PG 10 WC Materials Science, Ceramics SC Materials Science GA 713YN UT WOS:000184885700006 ER PT J AU Shepard, CL Cannon, BD Khaleel, MA AF Shepard, CL Cannon, BD Khaleel, MA TI Measurement of internal stress in glass articles SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article AB We have developed a method for measurement of internal stress in glass articles. The method uses Rayleigh-scattered light from a properly polarized laser beam propagating through glass at an oblique angle. This light is imaged with an electronic focal plane array camera. The method is similar to earlier published methods except for the inclusion of an externally controlled phase retarder. The phase retarder allows for the success of the method. The method is suitable for use on flat or curved glass and is applicable over a broad range of residual stresses. Experimental results are provided showing the in-plane stress throughout the thickness of a television glass sample. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Shepard, CL (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. OI khaleel, mohammad/0000-0001-7048-0749 NR 8 TC 8 Z9 8 U1 1 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 2003 VL 86 IS 8 BP 1353 EP 1359 PG 7 WC Materials Science, Ceramics SC Materials Science GA 713YN UT WOS:000184885700018 ER PT J AU Zhang, XF Lee, GY Chen, D Ritchie, RO De Jonghe, LC AF Zhang, XF Lee, GY Chen, D Ritchie, RO De Jonghe, LC TI Abrasive wear behavior of heat-treated ABC-silicon carbide SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID NITRIDE CERAMICS; ALUMINA; CREEP; FILM; SIZE AB Hot-pressed silicon carbide, containing aluminum, boron, and carbon additives (ABC-SiC), was subjected to three-body and two-body wear testing using diamond abrasives over a range of sizes. In general, the wear resistance of ABC-SiC, with suitable heat treatment, was superior to that of commercial SiC. When the fine-scale (3 mum) diamond abrasives were used, it was found that thermal annealing at 1300'C increased the resistance to three-body wear by a factor of almost three, and two-body wear by a factor of almost two, compared with as-hot-pressed samples. Higher annealing temperatures, however, led to a decline in wear resistance from its highest value. Similar behavior was seen for 1300degreesC-annealed samples subjected to 15 mum diamond abrasive, although higher-temperature annealing at 1500degrees-1600degreesC enhanced the wear resistance again. When coarse abrasives (72 mum) were used, the wear resistance progressively increased with increased annealing temperature from similar to1000degrees to 1600degreesC. Corresponding transmission and scanning electron microscopy studies indicated that, whereas transgranular, conchoidal cracking was dominant in the mild abrasive wear with fine-scale (3 mum) abrasives, intergranular cracking and subsequent grain pullout was far more predominant in the more severe abrasive wear with coarse abrasives. Because the hardness and indentation toughness were barely altered during thermal treatment, the observed wear behavior was attributed mainly to the thermally induced microstructural changes, including the crystallization of glassy grain-boundary films, the possible strengthening of the boundaries due to the enhancement of the aluminum, and the formation of aluminum-rich, coherent nanoscale precipitates in the matrix grains above 1300degreesC. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Engn Mech, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Shanghai Jiao Tong Univ, Dept Mat Sci & Engn, Shanghai 200030, Peoples R China. RP Zhang, XF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Ritchie, Robert/A-8066-2008 OI Ritchie, Robert/0000-0002-0501-6998 NR 20 TC 11 Z9 11 U1 0 U2 5 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 2003 VL 86 IS 8 BP 1370 EP 1378 PG 9 WC Materials Science, Ceramics SC Materials Science GA 713YN UT WOS:000184885700021 ER PT J AU Kruzic, JJ Ritchie, RO AF Kruzic, JJ Ritchie, RO TI Determining the toughness of ceramics from Vickers indentations using the crack-opening displacements: An experimental study SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID RESISTANCE-CURVE BEHAVIOR; SILICON-CARBIDE; SYSTEM; DAMAGE AB Recently, a method for evaluating the fracture toughness of ceramics has been proposed by Fett based on the computed crack-opening displacements of cracks emanating from Vickers hardness indentations. To verify this method, experiments have been conducted to determine the toughness of a commercial silicon carbide ceramic, Hexoloy SA, by measuring the crack-opening profiles of such Vickers indentation cracks. Although the obtained toughness value of K-o = 2.3 MPa.m(1/2) is within 10% of that measured using conventional fracture toughness testing, the computed crack-opening profiles corresponding to this toughness display poor agreement with those measured experimentally, raising concerns about the suitability of this method for determining the toughness of ceramics. The effects of subsurface cracking and cracking during loading are considered as possible causes of such discrepancies, with the former based on direct observations of lateral subsurface cracks below the indents. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. RP Kruzic, JJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Ritchie, Robert/A-8066-2008; Kruzic, Jamie/M-3558-2014 OI Ritchie, Robert/0000-0002-0501-6998; Kruzic, Jamie/0000-0002-9695-1921 NR 11 TC 44 Z9 45 U1 0 U2 10 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD AUG PY 2003 VL 86 IS 8 BP 1433 EP 1436 PG 4 WC Materials Science, Ceramics SC Materials Science GA 713YN UT WOS:000184885700033 ER PT J AU Schilling, B Row, RH Gibson, BW Guo, X Young, MM AF Schilling, B Row, RH Gibson, BW Guo, X Young, MM TI MS2Assign, automated assignment and nomenclature of tandem mass spectra of chemically crosslinked peptides SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID COLLISION-INDUCED DISSOCIATION; PROTEIN COMPLEXES; LINKING REAGENTS; SPECTROMETRY; IONS; IDENTIFICATION; FRAGMENTATION; DATABASE; NEBULIN AB In a previous report (Young et al., Proc. Natl. Acad. Sci. U.S.A. 2000, 97, 5802-5806), we provided a proof-of-principle for fold recognition of proteins using a homobifunctional amine-specific chemical crosslinking reagent in combination with mass spectrometry analysis and homology modeling. In this current work, we propose a systematic nomenclature to describe the types of peptides that are generated after proteolysis of crosslinked proteins, their fragmentation by tandem mass spectrometry, and an automated algorithm for MS/MS spectral assignment called "MS2Assign." Several examples are provided from crosslinked peptides and proteins including HIV-integrase, cytochrome c, ribonuclease A, myoglobin, cytidine 5'-monophosphate N-acetylneuraminic acid synthetase, and the peptide thymopentin. Tandem mass spectra were obtained from various crosslinked peptides using post source decay MALDI-TOF and collision induced dissociation on a quadrupole-TOF instrument, along with their automated interpretation using MS2Assign. A variety of possible outcomes are described and categorized according to the number of modified lysines and/or peptide chains involved, as well as the presence of singly modified (dead-end) lysine residues. In addition, the proteolysis and chromatographic conditions necessary for optimized crosslinked peptide recovery are presented. C1 Buck Inst Age Res, Novato, CA 94945 USA. Univ Calif San Francisco, Dept Pharmaceut Chem, San Francisco, CA 94143 USA. Sandia Natl Labs, Livermore, CA USA. RP Gibson, BW (reprint author), Buck Inst Age Res, 8001 Redwood Blvd, Novato, CA 94945 USA. FU NCRR NIH HHS [RR01614] NR 27 TC 173 Z9 179 U1 2 U2 16 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 AUG PY 2003 VL 14 IS 8 BP 834 EP 850 DI 10.1016/S1044-0305(03)00327-1 PG 17 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 708MD UT WOS:000184570500004 PM 12892908 ER PT J AU Barker, HW Goldstein, RK Stevens, DE AF Barker, HW Goldstein, RK Stevens, DE TI Monte Carlo simulation of solar reflectances for cloudy atmospheres SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID BOUNDARY-LAYER CLOUDS; PLANETARY ATMOSPHERES; SCATTERING; STRATOCUMULUS; FLUXES; MODEL AB Monte Carlo simulations of solar radiative transfer were performed for a well-resolved, large, three-dimensional (3D) domain of boundary layer cloud simulated by a cloud-resolving model. In order to represent 3D distributions of optical properties for; 2 3 106 cloudy cells, attenuation by droplets was handled by assigning each cell a cumulative distribution of extinction derived from either a model or an assumed discrete droplet size spectrum. This minimizes the required number of detailed phase functions. Likewise, to simulate statistically significant, high-resolution imagery, it was necessary to apply variance reduction techniques. Three techniques were developed for use with the local estimation method of computing reflectance rho. First, small fractions of rho come from numerous, small contributions of zeta computed at each scattering event. Terminating calculation of zeta when it falls below zeta(min) approximate to 10(-3) was found to impact estimates of rho minimally but reduced computation time by similar to10%. Second, large fractions of rho come from infrequent realizations of large zeta. When sampled poorly, they boost Monte Carlo noise significantly. Removing zeta - zeta(max), storing them in a domainwide reservoir, adding zeta(max) to local estimates of rho, and, at simulation's end, distributing the reservoir across the domain in proportion to local rho, tends to reduce variance much. This regionalization technique works well when the number of photons per unit area is small ( nominally less than or similar to 50 000). A value of zeta(max) approximate to 100 reduces variance of rho greatly with little impact on estimates of rho. Third, if zeta are computed using exact (e.g., Mie) phase functions for the first N scattering events, and thereafter a blunt-nosed corresponding phase function (e.g., Henyey-Greenstein) is used, production of large zeta is thwarted resulting in reduced variance and time required to achieve accurate estimates of rho. C1 Meteorol Serv Canada, Cloud Phys Res Div ARMP, Downsview, ON M3H 5T4, Canada. Univ British Columbia, Vancouver, BC V5Z 1M9, Canada. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Barker, HW (reprint author), Meteorol Serv Canada, Cloud Phys Res Div ARMP, 4905 Dufferin St, Downsview, ON M3H 5T4, Canada. NR 18 TC 29 Z9 29 U1 1 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD AUG PY 2003 VL 60 IS 16 BP 1881 EP 1894 DI 10.1175/1520-0469(2003)060<1881:MCSOSR>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 706TC UT WOS:000184470300001 ER PT J AU Coffey, GW Pederson, LR Rieke, PC AF Coffey, GW Pederson, LR Rieke, PC TI Competition between bulk and surface pathways in mixed ionic electronic conducting oxygen electrodes SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID OXIDE FUEL-CELLS; YTTRIA-STABILIZED ZIRCONIA; MICROSTRUCTURE-PROPERTY RELATIONS; ANODIC POLARIZATION PHENOMENA; ACTIVE REACTION SITES; SOFC AIR ELECTRODE; SR-DOPED LAMNO3; THIN-FILM; SOLID ELECTROLYTE; POROUS-ELECTRODES AB Two parallel pathways have been identified for oxygen reduction and evolution on mixed ionic electronic conductors (MIECs). Charge transfer may proceed by reaction at the triple-phase boundary to consume or produce oxygen adsorbed on the surface of the MIEC. Alternatively, charge transfer may proceed by reaction of oxygen with oxygen vacancies and electronic holes from the bulk of the MIEC with subsequent exchange of vacancies with the purely ionic conducting electrolyte. A continuum mass-transport model is developed describing the competition between these two charge-transfer pathways. Key to the model is treatment of the boundary condition at the MIEC-electrolyte interface. The absolute potential across this interface is used to relate the surface overpotential of each pathway in terms of the other and terms arising from the concentration overpotentials. The current attributable to each of the two pathways can be determined. Results show that the two pathways have different dependence on cell overpotential and competition for reagents creates complex mass-transport dependencies. One pathway may dominate at low overpotentials and the other at high overpotentials. The dependence of current on oxygen partial pressure is shown to transit from +1/2 power dependence to zero or negative power dependence as pressure increases, or to transit from zero or negative to +1/2 power depending on which pathway dominates. (C) 2003 The Electrochemical Society. C1 Pacific NW Natl Lab, Mat Synth & Modificat Grp, Richland, WA 99352 USA. RP Pacific NW Natl Lab, Mat Synth & Modificat Grp, Richland, WA 99352 USA. EM peter.rieke@pnl.gov NR 79 TC 32 Z9 32 U1 3 U2 17 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 EI 1945-7111 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 2003 VL 150 IS 8 BP A1139 EP A1151 DI 10.1149/1.1591758 PG 13 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 702BT UT WOS:000184205300019 ER PT J AU Doeff, MM Hollingsworth, J Shim, J Lee, YJ Striebel, K Reimer, JA Cairns, EJ AF Doeff, MM Hollingsworth, J Shim, J Lee, YJ Striebel, K Reimer, JA Cairns, EJ TI Sulfur-doped aluminum-substituted manganese oxide spinels for lithium-ion battery applications SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID CATHODE MATERIAL; LAYERED LIMNO2; LIXMN2O4 CATHODE; HIGH-CAPACITY; ELECTRODES; LIMN2O4; PHASE; CELLS; DIFFRACTION; STABILITY AB Spinels with nominal composition Li1.02Al0.25Mn1.75O3.97S0.03, Li1.02Al0.25Mn1.75O4, and Li1.02Al0.15Mn1.85O3.96S0.04 have been evaluated for their suitability as positive electrode materials in rechargeable lithium-ion batteries for electric (EV) and hybrid electric vehicle (HEV) applications. Li-7 magic angle spinning, nuclear magnetic resonance, X-ray diffraction, (XRD) and energy-dispersive spectroscopy experiments indicate that sulfur is most likely present as a trace impurity on the surface of the spinel particles rather than substituting for oxygen ions in the bulk, so it is unlikely to account for the previously reported enhanced cyclability of this material. Rather, the unusual particle morphology produced during calcination of some samples in the presence of sulfur compounds appears to impede (but does not completely prevent) conversion to the tetragonal phase that occurs at 3 V vs. Li and ameliorates the capacity fading associated with it. These materials exhibit reduced rate capability and capacity at 4 V, making them unsuitable for high energy density EV, or high power density applications. (C) 2003 The Electrochemical Society. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Doeff, MM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Cairns, Elton/E-8873-2012; OI Cairns, Elton/0000-0002-1179-7591; Lee, Young Joo/0000-0002-5782-6431; Doeff, Marca/0000-0002-2148-8047 NR 30 TC 6 Z9 6 U1 0 U2 26 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 2003 VL 150 IS 8 BP A1060 EP A1066 DI 10.1149/1.1586299 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 702BT UT WOS:000184205300007 ER PT J AU Pereira, N Balasubramanian, M Dupont, L McBreen, J Klein, LC Amatucci, GG AF Pereira, N Balasubramanian, M Dupont, L McBreen, J Klein, LC Amatucci, GG TI The Electrochemistry of germanium nitride with lithium SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID TRANSITION-METAL NITRIDE; THIN-FILM LITHIUM; X-RAY-DIFFRACTION; ION BATTERIES; ANODE MATERIAL; LI DEINTERCALATION; STRUCTURAL-CHANGE; TIN; PERFORMANCE; LI2.6CO0.4N AB Ge3N4 was investigated for its electrochemical activity with Lithium as a possible negative electrode material for Li-ion batteries. Ge3N4 was found to reversibly react with Li, exhibiting high capacity, 500 mAh/g, and maintaining good cycling stability. The reaction mechanism of Ge3N4 with lithium was investigated in detail using in situ and ex situ X-ray diffraction (XRD) in reflection, in situ XRD in transmission, ex situ transmission electron microscopy, and selected-area electron diffraction (SAED). The two phases, alpha- and beta-Ge3N4, of the electrode material mostly maintained their respective crystalline microstructure during cycling. A substantial integrated intensity decrease in the XRD Bragg reflections observed during the first lithiation and the concurrent emergence of diffuse rings in SAED suggest the reaction of Ge3N4 with lithium may be limited thereby converting only the outermost shell of the Ge3N4 crystal. The identification of alpha-Li3N and Ge at the end of the first delithiation using SAED supports a lithium/metal nitride conversion reaction process. The formation of the Li3N matrix was found to be consistent with a 50% irreversible capacity loss in the first cycle. (C) 2003 The Electrochemical Society. C1 Rutgers State Univ, Dept Ceram & Mat Engn, Energy Storage Res Grp, Piscataway, NJ 08854 USA. SAJC, Mclean, VA 22102 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Picardie, Lab React & Chim Solides, F-80039 Amiens, France. RP Amatucci, GG (reprint author), Rutgers State Univ, Dept Ceram & Mat Engn, Energy Storage Res Grp, Piscataway, NJ 08854 USA. RI dupont, loic/B-6713-2013 OI dupont, loic/0000-0003-3810-6356 NR 27 TC 67 Z9 69 U1 6 U2 62 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 2003 VL 150 IS 8 BP A1118 EP A1128 DI 10.1149/1.1587724 PG 11 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 702BT UT WOS:000184205300016 ER PT J AU Wang, JX Brankovic, SR Zhu, Y Hanson, JC Adzic, RR AF Wang, JX Brankovic, SR Zhu, Y Hanson, JC Adzic, RR TI Kinetic characterization of PtRu fuel cell anode catalysts made by spontaneous Pt deposition on Ru nanoparticles SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID RU(0001) SURFACE; CARBON-MONOXIDE; CO ADSORPTION; OXIDATION; PLATINUM; ELECTROCATALYSTS; ELECTROOXIDATION; ELECTRODE; RUTHENIUM; CLUSTERS AB Hydrogen oxidation kinetics without and with trace amounts of CO in H-2 were investigated for carbon-supported catalysts consisting of Pt submonolayers on Ru nanoparticles prepared by spontaneous deposition and commercial Pt, Ru, and PtRu alloy catalysts. Thin catalyst layers were deposited onto a glassy carbon rotating disk electrode without using Nafion film to stabilize them. Nonlinear fittings of the entire polarization curves at several rotation rates were used to determine the exchange current, the Tafel slope, and the Levich slope. To ensure full utilization of the catalyst, the mass-specific activity was determined by finding the minimum Pt loading needed to have all three kinetic parameters close to those found for a polycrystalline Pt electrode. For the PtRu20, PtRu10, and PtRu5 samples prepared by spontaneous deposition of 1/9 to 4/9 monolayer Pt on Ru, the minimum loading is 5 nmol/cm(2) (1 mug(Pt)/cm(2)). This is only one-third of that for Pt or PtRu (E-TEK) catalysts and only double the atomic density of a Pt(111) surface, indicating that the high activity of Pt metal for hydrogen oxidation is retained when the atomic assemblies are reduced to submonolayer level on Ru. The enhanced CO tolerance was studied at low potentials by correlating the loss of the activity in 0.1% CO/H-2 with the CO coverage on Pt and Ru sites. (C) 2003 The Electrochemical Society. C1 Brookhaven Natl Lab, Dept Mat Sci, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Wang, JX (reprint author), Brookhaven Natl Lab, Dept Mat Sci, Upton, NY 11973 USA. RI Hanson, jonathan/E-3517-2010; Wang, Jia/B-6346-2011 NR 32 TC 63 Z9 65 U1 3 U2 29 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 2003 VL 150 IS 8 BP A1108 EP A1117 DI 10.1149/1.1579481 PG 10 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 702BT UT WOS:000184205300015 ER PT J AU Williford, RE Chick, LA Maupin, GD Simner, SP Stevenson, JW AF Williford, RE Chick, LA Maupin, GD Simner, SP Stevenson, JW TI Diffusion limitations in the porous anodes of SOFCs SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID OXIDE FUEL-CELLS; ZIRCONIA CERMET ELECTRODES; POLARIZATION CHARACTERISTICS; REACTION-MECHANISM; INTERFACE; HYDROGEN; SURFACE; YSZ; NI; ADSORPTION AB Concentration polarization is important because it determines the maximum power output of a solid oxide fuel cell (SOFC) at high fuel utilization. Anodic concentration polarization occurs when the demand for reactants exceeds the capacity of the porous cermet anode to supply them by gas diffusion mechanisms. High tortuosities (bulk diffusion resistances) are often assumed to explain this behavior. However, recent experiments show that anodic concentration polarization originates in the immediate vicinity of the reactive triple phase boundary (TPB) sites near the anode/electrolyte interface. A model is proposed to describe how concentration polarization is controlled by two localized phenomena: competetive adsorption of reactants in areas adjacent to the reactive TPB sites, followed by relatively slow surface diffusion to the reactive sites. Results suggest that future SOFC anode design improvements should focus on optimization of the reactive area, adsorption, and surface diffusion at the anode/electrolyte interface. (C) 2003 The Electrochemical Society. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Williford, RE (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 39 TC 105 Z9 105 U1 3 U2 29 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 2003 VL 150 IS 8 BP A1067 EP A1072 DI 10.1149/1.1586300 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 702BT UT WOS:000184205300008 ER PT J AU Yang, ZG Meinhardt, KD Stevenson, JW AF Yang, ZG Meinhardt, KD Stevenson, JW TI Chemical compatibility of barium-calcium-aluminosilicate-based sealing glasses with the ferritic stainless steel interconnect in SOFCs SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID OXIDE FUEL-CELL; CHROMIUM-CONTAINING ALLOY; DEGRADATION; CATHODE; SEPARATOR AB In most planar solid oxide fuel cell (SOFC) stack designs, the interconnect, which is typically made from a ferritic stainless steel (SS), is hermetically sealed to the ceramic positive electrode-electrolyte-negative electrode by a sealing glass. To maintain the structural stability and minimize degradation of the stack performance, the sealing glass must be chemically compatible with the SS interconnect. In this study, a barium-calcium-aluminosilicate (BCAS)-based glass ceramic, specifically developed as a sealant in SOFC stacks, and a ferritic SS (AISI446) were selected as examples to increase the understanding of the chemical compatibility issues in SOFCs. Evaluation of the interfaces of coupon joints indicated that interactions between the BCAS glass ceramic and the ferritic SS were dependent on the exposure conditions. At the edges of joints, where oxygen or air was accessible, the interaction often led to the formation of BaCrO4, while in the interior of the joints, chromium or chromia dissolved into the glass to form a thin layer of chromium-rich solid solution. It was also found that, in the interior of the joints, the interaction often resulted in the formation of pores aligned along the interface. It appears the pore formation along the interface can be avoided through a preheat treatment. (C) 2003 The Electrochemical Society. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Yang, ZG (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 21 TC 106 Z9 108 U1 0 U2 15 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 2003 VL 150 IS 8 BP A1095 EP A1101 DI 10.1149/1.1590325 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 702BT UT WOS:000184205300013 ER PT J AU Gomadam, PM Weidner, JW Zawodzinski, TA Saab, AP AF Gomadam, PM Weidner, JW Zawodzinski, TA Saab, AP TI Theoretical analysis for obtaining physical properties of composite electrodes SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID INTERDIGITATED MICROARRAY ELECTRODES; SITU CONDUCTIVITY MEASUREMENTS; LITHIUM INSERTION/EXTRACTION; DIFFUSION-COEFFICIENT; IMPEDANCE RESPONSE; CELL; FILM AB A theoretical analysis is presented that allows in situ measurements of the physical properties of a composite electrode, namely, the electronic conductivity, the ionic conductivity, the exchange-current density, and the double-layer capacitance. Use is made of the current-voltage responses of the composite electrode to dc and ac polarizations under three different experimental configurations. This analysis allows the physical properties to be obtained even when the various resistances in the composite (e.g., ionic, electronic, and charge-transfer) are of comparable values. (C) 2003 The Electrochemical Society. C1 Univ S Carolina, Dept Chem Engn, Ctr Electrochem Engn, Columbia, SC 29208 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Weidner, JW (reprint author), Univ S Carolina, Dept Chem Engn, Ctr Electrochem Engn, Columbia, SC 29208 USA. OI Weidner, John/0000-0002-3928-9740 NR 15 TC 17 Z9 17 U1 0 U2 9 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD AUG PY 2003 VL 150 IS 8 BP E371 EP E376 DI 10.1149/1.1586301 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 702BT UT WOS:000184205300040 ER PT J AU Rupert, DR AF Rupert, DR TI Diversity at the laboratory SO LABORATORY MEDICINE LA English DT Article AB Many organizations, including Oak Ridge National Laboratory (ORNL), are faced with the challenge of managing diversity. Organizations that understand, recognize, and respect differences and learn to capitalize on the creativity that differences can bring will survive the challenges of the changing dynamics of the 21st century workplace. To meet these challenges, ORNL has established a mechanism for creating an inclusive organization where high performance is supported and where employees are respected, recognized, and rewarded according to their contributions. C1 Oak Ridge Natl Lab, Staffing Management Program, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Divers Program, Oak Ridge, TN 37831 USA. RP Rupert, DR (reprint author), Oak Ridge Natl Lab, Staffing Management Program, Oak Ridge, TN 37831 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC CLINICAL PATHOLOGY PI CHICAGO PA 2100 W HARRISON ST, CHICAGO, IL 60612 USA SN 0007-5027 J9 LAB MED JI Lab. Med. PD AUG PY 2003 VL 34 IS 8 BP 577 EP 580 DI 10.1309/54R48GV8X6THYHKL PG 4 WC Medical Laboratory Technology SC Medical Laboratory Technology GA 706VV UT WOS:000184476500012 ER PT J AU Anitescu, M Hart, GD AF Anitescu, M Hart, GD TI Solving nonconvex problems of multibody dynamics with joints, contact, and small friction by successive convex relaxation SO MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES LA English DT Article; Proceedings Paper CT Conference of the NATO Advanced-Study-Institute on Virtual Nonlinear Multibody Systems CY JUN 23-JUL 03, 2002 CL PRAGUE, CZECH REPUBLIC SP NATO Adv Study Inst DE Coulomb friction; linear complementarity; fixed-point iteration ID RIGID-BODY DYNAMICS AB Time-stepping methods using impulse-velocity approaches are guaranteed to have a solution for any friction coefficient, but they may have nonconvex solution sets. We present an example of a configuration with a nonconvex solution set for any nonzero value of the friction coefficient. We construct an iterative algorithm that solves convex subproblems and that is guaranteed, for sufficiently small friction coefficients, to retrieve, at a linear convergence rate, the velocity solution of the nonconvex linear complementarity problem whenever the frictionless configuration can be disassembled. In addition, we show that one step of the iterative algorithm provides an excellent approximation to the velocity solution of the original, possibly nonconvex, problem if the product between the friction coefficient and the slip velocity is small. C1 Univ Pittsburgh, Dept Math, Pittsburgh, PA 15260 USA. RP Anitescu, M (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave,Bldg 221, Argonne, IL 60439 USA. NR 21 TC 7 Z9 7 U1 0 U2 0 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1539-7734 J9 MECH BASED DES STRUC JI Mech. Based Des. Struct. Mech. PD AUG PY 2003 VL 31 IS 3 BP 335 EP 356 DI 10.1081/SME-120022854 PG 22 WC Mechanics SC Mechanics GA 755CE UT WOS:000187385500004 ER PT J AU Burmeister, J Riley, K Coderre, JA Harling, OK Ma, R Wielopolski, L Kota, C Maughan, RL AF Burmeister, J Riley, K Coderre, JA Harling, OK Ma, R Wielopolski, L Kota, C Maughan, RL TI Microdosimetric intercomparison of BNCT beams at BNL and MIT SO MEDICAL PHYSICS LA English DT Article DE BNCT; microdosimetry; epithermal neutrons ID NEUTRON-CAPTURE THERAPY; EQUIVALENT PROPORTIONAL-COUNTERS; RESEARCH REACTOR; DOSIMETRY; TISSUE; PHANTOMS; BNCEFNT; SPECTRA AB Microdosimetric measurements have been performed at the clinical beam intensities in two epithermal neutron beams, the Brookhaven Medical Research Reactor and the M67 beam at the Massachusetts Institute of Technology Research Reactor, which have been used to treat patients with Boron Neutron Capture Therapy (BNCT). These measurements offer an independent assessment of the dosimetry used at these two facilities, as well as provide information about the radiation quality not obtainable from conventional macrodosimetric techniques. Moreover, they provide a direct measurement of the absorbed dose resulting from the BNC reaction. BNC absorbed doses measured within this study are approximately 15% lower than those estimated using foil activation at both MIT and BNL. Finally, an intercomparison of the characteristics and radiation quality of these two clinical beams is presented. The techniques described here allow an accurate quantitative comparison of the physical absorbed dose as well as a measure of the biological effectiveness of the absorbed dose delivered by different epithermal beams. No statistically significant differences were observed in the predicted RBEs of these two beams. The methodology presented here can help to facilitate the effective sharing of clinical results in an effort to demonstrate the clinical utility of BNCT. (C) 2003 American Association of Physicists in Medicine. C1 Wayne State Univ, Detroit, MI 48201 USA. Harper Univ Hosp, Karmanos Canc Inst, Gershenson Radiat Oncol Ctr, Detroit, MI 48201 USA. MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. MIT, Nucl Reactor Lab, Cambridge, MA 02139 USA. Mem Sloan Kettering Canc Ctr, Dept Phys Med, Commack, NY 11725 USA. Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. Univ Penn, Dept Radiat Oncol, Philadelphia, PA 19104 USA. RP Burmeister, J (reprint author), Harper Grace Hosp, Gershenson ROC, 3990 John R, Detroit, MI 48201 USA. EM burmeist@kci.wayne.edu NR 27 TC 4 Z9 4 U1 0 U2 2 PU AMER ASSOC PHYSICISTS MEDICINE AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD AUG PY 2003 VL 30 IS 8 BP 2131 EP 2139 DI 10.1118/1.1589612 PG 9 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 713BE UT WOS:000184834600019 PM 12945978 ER PT J AU Cummings, DE Snoeyenbos-West, OL Newby, DT Niggemyer, AM Lovley, DR Achenbach, LA Rosenzweig, RF AF Cummings, DE Snoeyenbos-West, OL Newby, DT Niggemyer, AM Lovley, DR Achenbach, LA Rosenzweig, RF TI Diversity of geobacteraceae species inhabiting metal-polluted freshwater lake sediments ascertained by 16S rDNA analyses SO MICROBIAL ECOLOGY LA English DT Article ID MICROBIAL FE(III) REDUCTION; POLYMERASE-CHAIN-REACTION; RIBOSOMAL-RNA; FE(III)-REDUCING BACTERIUM; CONTAMINATED AQUIFER; COEUR-DALENE; GEN. NOV.; TRICHLOROBACTER-THIOGENES; ARSENIC MOBILIZATION; FERRIC-OXIDE AB he abundance, distribution, and phylogenetic diversity of members of the Fe (III)-reducing family Geobacteraceae were studied along a gradient of metal contaminants in Lake Coeur d'Alene, Idaho. Partial 16S rRNA gene fragments were amplified by PCR using primers directed toward conserved regions of the gene within the family Geobacteraceae. Analysis of amplicons separated by denaturing gradient gel electrophoresis (DGGE) suggested within-site variation was as great as between-site variation. Amplicons were cloned and grouped by RFLP type and DGGE migration distance and representatives were sequenced. Grouping clones with 3% or less sequence dissimilarity, 15 distinct phylotypes were identified compared to 16 distinct DGGE bands. Only 1 phylotype was recovered from all sites. This clone, B14, is most closely related to Geobacter metallireducens and constituted a greater portion of the pristine community than of the contaminated communities. A second phylotype, Q2, predominated in the contaminated communities and was notably absent from the pristine libraries. Clone Q2 presents a high degree of sequence similarity to two Geobacter spp. previously isolated from this region of Lake Coeur d'Alene. Six phylotypes were unique to the contaminated sediments, whereas two were found only in the pristine sediments. Indices of diversity (Shannon and Simpson) were consistently higher when calculated with DGGE data than when clone library data were used. Most-probable-number PCR and real-time PCR suggested that the Geobacteraceae phylotypes were spread relatively evenly across all three sites along the gradient. Our data indicate that the Geobacteraceae are diverse and abundant in Lake Coeur d'Alene sediments, regardless of metals content. These results provide insight into the ability of dissimilatory Fe(III)-reducing bacteria to colonize habitats with elevated metal concentrations, and they have important implications for the management and remediation of metal-contaminated sites. C1 Univ Idaho, Dept Biol Sci, Moscow, ID 83844 USA. Univ Idaho, Dept Microbiol Mol Biol & Biochem, Moscow, ID 83844 USA. Univ Massachusetts, Dept Microbiol, Amherst, MA 01003 USA. So Illinois Univ, Dept Microbiol, Carbondale, IL 62901 USA. So Illinois Univ, Ctr Systemat Biol, Carbondale, IL 62901 USA. Idaho Natl Lab, Dept Biotechnol, Idaho Falls, ID 83415 USA. Smith Coll, Dept Biol Sci, Northampton, MA 01063 USA. Surface Water Resources Inc, Sacramento, CA 95825 USA. Univ Montana, Div Biol Sci, Missoula, MT 59812 USA. RP Univ Idaho, Dept Biol Sci, Moscow, ID 83844 USA. EM rrose@selway.umt.edu OI Snoeyenbos-West, Oona/0000-0001-9146-7244 NR 60 TC 77 Z9 87 U1 3 U2 43 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0095-3628 EI 1432-184X J9 MICROB ECOL JI Microb. Ecol. PD AUG PY 2003 VL 46 IS 2 BP 257 EP 269 DI 10.1007/s00248-002-0005-8 PG 13 WC Ecology; Marine & Freshwater Biology; Microbiology SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Microbiology GA 732NV UT WOS:000185953200010 PM 14708750 ER PT J AU Yamamoto, K Ishiai, M Matsushita, N Arakawa, H Lamerdin, JE Buerstedde, JM Tanimoto, M Harada, M Thompson, LH Takata, M AF Yamamoto, K Ishiai, M Matsushita, N Arakawa, H Lamerdin, JE Buerstedde, JM Tanimoto, M Harada, M Thompson, LH Takata, M TI Fanconi anemia FANCG protein in mitigating radiation- and enzyme-induced DNA double-strand breaks by homologous recombination in vertebrate cells SO MOLECULAR AND CELLULAR BIOLOGY LA English DT Article ID SISTER-CHROMATID EXCHANGES; 5 RAD51 PARALOGS; GROUP-G GENE; CHROMOSOMAL INTEGRITY; REPAIR; BRCA2; COMPLEX; FANCG/XRCC9; STABILITY; PATHWAYS AB The rare hereditary disorder Fanconi anemia (FA) is characterized by progressive bone marrow failure, congenital skeletal abnormality, elevated susceptibility to cancer, and cellular hypersensitivity to DNA cross-linking chemicals and sometimes other DNA-damaging agents. Molecular cloning identified six causative genes (FANCA, -C, -D2, -E, -F, and -G) encoding a multiprotein complex whose precise biochemical function remains elusive. Recent studies implicate this complex in DNA damage responses that are linked to the breast cancer susceptibility proteins BRCA1 and BRCA2. Mutations in BRCA2, which participates in homologous recombination (FIR), are the underlying cause in some FA patients. To elucidate the roles of FA genes in HR, we disrupted the FANCG/XRCC9 locus in the chicken B-cell line DT40. FANCG-deficient DT40 cells resemble mammalian fancg mutants in that they are sensitive to killing by cisplatin and mitomycin C (MMC) and exhibit increased MMC and radiation-induced chromosome breakage. We find that the repair of I-SceI-induced chromosomal double-strand breaks (DSBs) by HR is decreased similar to9-fold in fancg cells compared with the parental and FANCG-complemented cells. In addition, the efficiency of gene targeting is mildly decreased in FANCG-deficient cells, but depends on the specific locus. We conclude that FANCG is required for efficient HR-mediated repair of at least some types of DSBs. C1 Kawasaki Med Univ, Dept Immunol & Mol Genet, Kurashiki, Okayama 7010192, Japan. Okayama Univ, Sch Med, Dept Internal Med, Okayama 7008558, Japan. Kyushu Univ, Sch Med, Dept Internal Med, Fukuoka 8128582, Japan. GSF, Inst Mol Radiobiol, D-85764 Munich, Germany. Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Takata, M (reprint author), Kawasaki Med Univ, Dept Immunol & Mol Genet, Kurashiki, Okayama 7010192, Japan. NR 64 TC 110 Z9 112 U1 1 U2 6 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0270-7306 J9 MOL CELL BIOL JI Mol. Cell. Biol. PD AUG PY 2003 VL 23 IS 15 BP 5421 EP 5430 DI 10.1128/MCB.23.15.5421-5430.2003 PG 10 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 703MP UT WOS:000184283700029 PM 12861027 ER PT J AU Rothkamm, K Kruger, I Thompson, LH Lobrich, M AF Rothkamm, K Kruger, I Thompson, LH Lobrich, M TI Pathways of DNA double-strand break repair during the mammalian cell cycle SO MOLECULAR AND CELLULAR BIOLOGY LA English DT Article ID DEPENDENT PROTEIN-KINASE; ATAXIA-TELANGIECTASIA CELLS; SENSITIVE IRS MUTANTS; HUMAN RAD51 PROTEIN; HAMSTER OVARY CELL; HOMOLOGOUS RECOMBINATION; IONIZING-RADIATION; VERTEBRATE CELLS; CHROMOSOME STABILITY; REPLICATION ARREST AB Little is known about the quantitative contributions of nonhomologous end joining (NHEJ) and homologous recombination (HR) to DNA double-strand break (DSB) repair in different cell cycle phases after physiologically relevant doses of ionizing radiation. Using immunofluorescence detection of gamma-H2AX nuclear foci as a novel approach for monitoring the repair of DSBs, we show here that NHEJ-defective hamster cells (CHO mutant V3 cells) have strongly reduced repair in all cell cycle phases after I Gy of irradiation. In contrast, HR-defective CHO irs1SF cells have a minor repair defect in G(1), greater impairment in S, and a substantial defect in late S/G(2). Furthermore, the radiosensitivity of irs1SF cells is slight in G(1) but dramatically higher in late S/G(2), while V3 cells show high sensitivity throughout the cell cycle. These findings show that NHEJ is important in all cell cycle phases, while HR is particularly important in late S/G(2), where both pathways contribute to repair and radioresistance. In contrast to DSBs produced by ionizing radiation, DSBs produced by the replication inhibitor aphidicolin are repaired entirely by HR. irs1SF, but not V3, cells show hypersensitivity to aphidicolin treatment. These data provide the first evaluation of the cell cycle-specific contributions of NHEJ and HR to the repair of radiation-induced versus replication-associated DSBs. C1 Univ Saarland, Fachrichtung Biophys, D-66421 Homburg, Germany. Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Lobrich, M (reprint author), Univ Saarland, Fachrichtung Biophys, D-66421 Homburg, Germany. RI Rothkamm, Kai/A-2164-2014 OI Rothkamm, Kai/0000-0001-7414-5729 NR 73 TC 680 Z9 697 U1 3 U2 46 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0270-7306 J9 MOL CELL BIOL JI Mol. Cell. Biol. PD AUG PY 2003 VL 23 IS 16 BP 5706 EP 5715 DI 10.1128/MCB.23.16.5706.5715.2003 PG 10 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 707TZ UT WOS:000184527100019 PM 12897142 ER PT J AU Przybyla-Zawislak, BD Srivastava, PK Vazquez-Matias, J Mohrenweiser, HW Maxwell, JE Hammock, BD Bradbury, JA Enayetallah, AE Zeldin, DC Grant, DF AF Przybyla-Zawislak, BD Srivastava, PK Vazquez-Matias, J Mohrenweiser, HW Maxwell, JE Hammock, BD Bradbury, JA Enayetallah, AE Zeldin, DC Grant, DF TI Polymorphisms in human soluble epoxide hydrolase SO MOLECULAR PHARMACOLOGY LA English DT Article ID BLOOD-PRESSURE REGULATION; ARACHIDONIC-ACID; CATALYTIC MECHANISM; MOUSE-LIVER; GENE EPHX2; IDENTIFICATION; RAT; HYPERTENSION; PURIFICATION; DETERMINANTS AB Human soluble epoxide hydrolase (hsEH) metabolizes a variety of epoxides to the corresponding vicinal diols. Arachidonic and linoleic acid epoxides are thought to be endogenous substrates for hsEH. Enzyme activity in humans shows high interindividual variation ( e. g., 500-fold in liver) suggesting the existence of regulatory and/or structural gene polymorphisms. We resequenced each of the 19 exons of the hsEH gene (EPHX2) from 72 persons representing black, Asian, and white populations. A variety of polymorphisms was found, six of which result in amino acid substitutions. Amino acid variants were localized on the crystal structure of the mouse sEH, resulting in the prediction that at least two of these (Arg287Gln and Arg103Cys) might significantly affect enzyme function. The six variants of the hsEH cDNA corresponding to each single polymorphism and one corresponding to a double polymorphism were then constructed by site-directed mutagenesis and expressed in insect cells. As predicted, Arg287Gln and the double mutant Arg287Gln/Arg103Cys showed decreased enzyme activity using trans-stilbene oxide, trans-diphenylpropene oxide, and 14,15-epoxyeicosatrienoic acid as substrates. Lys55Arg and Cys154Tyr mutants had elevated activity for all three substrates. Detailed kinetic studies revealed that the double mutant Arg287Gln/Arg103Cys showed significant differences in K-m and V-max. In addition, stability studies showed that the double mutant was less stable than wild-type protein when incubated at 37 degreesC. These results suggest that at least six hsEH variants exist in the human population and that at least four of these may influence hsEH-mediated metabolism of exogenous and endogenous epoxide substrates in vivo. C1 Univ Arkansas Med Sci, Dept Pharmacol & Toxicol, Little Rock, AR 72205 USA. Univ Connecticut, Dept Pharmaceut Sci, Storrs, CT USA. Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA USA. Univ Calif Davis, Dept Entomol, Davis, CA 95616 USA. Univ Calif Davis, Ctr Canc Res, Davis, CA 95616 USA. NIEHS, Div Intramural Res, NIH, Res Triangle Pk, NC 27709 USA. RP Zeldin, DC (reprint author), Univ Arkansas Med Sci, Dept Pharmacol & Toxicol, Little Rock, AR 72205 USA. FU NIEHS NIH HHS [R37-ES02710, P42-ES04699, P30-ES05707]; NIGMS NIH HHS [GM56708] NR 36 TC 89 Z9 94 U1 0 U2 2 PU AMER SOC PHARMACOLOGY EXPERIMENTAL THERAPEUTICS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0026-895X J9 MOL PHARMACOL JI Mol. Pharmacol. PD AUG PY 2003 VL 64 IS 2 BP 482 EP 490 DI 10.1124/mol.64.2.482 PG 9 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 702JN UT WOS:000184220900033 PM 12869654 ER PT J AU Stalker, JR Knupp, KR AF Stalker, JR Knupp, KR TI Cell merger potential in multicell thunderstorms of weakly sheared environments: cell separation distance versus planetary boundary layer depth SO MONTHLY WEATHER REVIEW LA English DT Article ID CLOUD MICROPHYSICS PARAMETERIZATION; SEA-BREEZE FRONT; SOUTH FLORIDA; DOPPLER RADAR; NUMERICAL EXPERIMENTS; CUMULUS CLOUDS; WEST TEXAS; CONVECTION; MODEL; SIMULATION AB Using high-resolution three-dimensional numerical experiments, this paper shows that the cell separation distance scales as 0.75 times the planetary boundary layer (PBL) depth for successful cell mergers between constructively interacting cells within multicell thunderstorms. This boundary layer scaling is determined from several simulations of convective cell pairs with a fixed PBL depth and is shown to be valid for other sensitivity simulations with larger PBL depths. This research establishes a robust and quantitative relation between prestorm ambient conditions and cell merger potential useful for research efforts on the multifaceted cell merger process of multicell thunderstorms. The weakly sheared ambient prestorm conditions of the 9 August 1991 Convection and Precipitation/Electrification Experiment (CaPE) multicell thunderstorm are used to initialize the cell pair simulations. Since ambient wind and wind shear are assumed to be zero, only simple cell mergers, defined in this study as those between cell updraft cores joined but not overlapping in the convective stage, are shown to be possible. The coarse-resolution simulations of Stalker suggest that ambient wind shear may be necessary for forced cell mergers, defined in this study as those in which the initial updraft cores are found apart. The scenarios of overlapping initial updraft cores for cell merger are considered physically invalid in this study. C1 Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. Univ Alabama, Dept Atmospher Sci, Natl Space Sci & Technol Ctr, Huntsville, AL 35899 USA. RP Stalker, JR (reprint author), Los Alamos Natl Lab, Div Earth & Environm Sci, EES-8,Mail Stop D401, Los Alamos, NM 87545 USA. NR 61 TC 8 Z9 9 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD AUG PY 2003 VL 131 IS 8 BP 1678 EP 1695 DI 10.1175//2556.1 PG 18 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 704NY UT WOS:000184346800013 ER PT J AU Hallen, HE Watling, R Adams, GC AF Hallen, HE Watling, R Adams, GC TI Taxonomy and toxicity of Conocybe lactea and related species SO MYCOLOGICAL RESEARCH LA English DT Article ID RIBOSOMAL DNA-SEQUENCES; IDENTIFICATION; PSILOCYBE; PHALLOTOXINS; SPECIFICITY; SENSITIVITY; DIVERGENT; AMATOXINS; EVOLUTION; NUCLEAR AB Conocybe lactea was examined as part of a larger study on the distribution of amatoxins and phallotoxins in fungi, and the taxonomic relationships between these fungi. As amatoxins are present in the congener C. filaris, the locally abundant C. lactea was examined using HPLC and mass spectroscopy. Amatoxins were not found in C. lactea, but the related phallotoxins were present in small quantities making it the first fungus outside of the genus Amanita in which phallotoxins have been detected. Despite the presence of a related toxin, C. lactea was found not to be taxonomically close to C. filaris. Phylogenetic analyses using nuclear ribosomal RNA genes indicated that North American specimens of C. lactea were conspecific with North American specimens of C. crispa in Conocybe sect. Candidae. European C. crispa was a distinct taxon. The implications of the use of the name C. albipes for these taxa are discussed. Nucleotide data confirmed placement of the sequestrate taxon Gastrocybe lateritia in sect. Candidae, but as a distinct taxon. It is hypothesized that the unique sequestrate morphology of G. lateritia may be caused by a bacterial infection. C1 Michigan State Univ, DOE Plant Res Lab, E Lansing, MI 48824 USA. Caledonian Mycol Enterprises, Edinburgh EH4 3HU, Midlothian, Scotland. Amer Type Culture Collect, Manassas, VA 20110 USA. RP Hallen, HE (reprint author), Michigan State Univ, DOE Plant Res Lab, E Lansing, MI 48824 USA. OI Hallen-Adams, Heather/0000-0002-1929-725X FU NCRR NIH HHS [DRR-00480] NR 46 TC 30 Z9 32 U1 0 U2 13 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH ST, NEW YORK, NY 10011-4221 USA SN 0953-7562 J9 MYCOL RES JI Mycol. Res. PD AUG PY 2003 VL 107 BP 969 EP 979 DI 10.1017/S0953756203008190 PN 8 PG 11 WC Mycology SC Mycology GA 728DP UT WOS:000185700200005 PM 14531619 ER PT J AU Rivera, JL McCabe, C Cummings, PT AF Rivera, JL McCabe, C Cummings, PT TI Oscillatory behavior of double-walled nanotubes under extension: A simple nanoscale damped spring SO NANO LETTERS LA English DT Article ID MULTIWALLED CARBON NANOTUBES; MOLECULAR-DYNAMICS SIMULATIONS; LOW-FRICTION; FORCE-FIELD; SINGLE-WALL; SYMMETRY; BEARINGS; CRYSTALS AB Computer simulations of double-walled carbon nanotubes show that if the inner nanotube is pulled out part of the way and then released, then the inner tube exhibits damped oscillatory behavior at gigahertz frequencies. A simple mathematical model, formulated in terms of macroscopic ideas of friction, is shown to predict the observed behavior to a high degree of accuracy. C1 Vanderbilt Univ, Dept Chem Engn, Nashville, TN 37235 USA. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA. Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. RP Cummings, PT (reprint author), Vanderbilt Univ, Dept Chem Engn, 221 Kirkland Hall, Nashville, TN 37235 USA. EM peter.cummings@vanderbilt.edu RI Rivera, Jose/A-2795-2008; McCabe, Clare/I-8017-2012; Cummings, Peter/B-8762-2013 OI Rivera, Jose/0000-0002-6985-7841; McCabe, Clare/0000-0002-8552-9135; Cummings, Peter/0000-0002-9766-2216 NR 26 TC 144 Z9 147 U1 0 U2 25 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 AUG PY 2003 VL 3 IS 8 BP 1001 EP 1005 DI 10.1021/nl034171o 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 714BL UT WOS:000184892400003 ER PT J AU Maiti, A Rodriguez, JA Law, M Kung, P McKinney, JR Yang, PD AF Maiti, A Rodriguez, JA Law, M Kung, P McKinney, JR Yang, PD TI SnO2 nanoribbons as NO2 sensors: Insights from first principles calculations SO NANO LETTERS LA English DT Article ID ROOM-TEMPERATURE; MOLECULES; OXIDE; NANOSENSORS; SWITCHES AB SnO2 nanoribbons with exposed (1 0 (1) over bar) and (0 1 0) surfaces have recently been demonstrated to be highly effective NO2 sensors even at room temperature. The sensing mechanism is examined here through first principles density functional theory (DFT) calculations. We show that the most stable adsorbed species involve an unexpected NO3 group doubly bonded to Sn centers. Significant electron transfer to the adatoms explains an orders-of-magnitude drop in electrical conductance. X-ray absorption spectroscopy indicates predominantly NO3 species on the surface, and computed binding energies are consistent with adsorbate stability up to 700 K. Nanoribbon responses to O-2 and CO sensing are also investigated. C1 Accelrys Inc, San Diego, CA 92121 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11953 USA. Univ Calif Berkeley, Mat Sci Div, Berkeley, CA 94720 USA. RP Maiti, A (reprint author), Accelrys Inc, 9685 Scranton Rd, San Diego, CA 92121 USA. NR 20 TC 128 Z9 130 U1 4 U2 57 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 AUG PY 2003 VL 3 IS 8 BP 1025 EP 1028 DI 10.1021/nl034235v PG 4 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 714BL UT WOS:000184892400007 ER PT J AU Hernandez, E Meunier, V Smith, BW Rurali, R Terrones, H Nardelli, MB Terrones, M Luzzi, DE Charlier, JC AF Hernandez, E Meunier, V Smith, BW Rurali, R Terrones, H Nardelli, MB Terrones, M Luzzi, DE Charlier, JC TI Fullerene coalescence in nanopeapods: A path to novel tubular carbon SO NANO LETTERS LA English DT Article ID ELECTRON-IRRADIATION; MOLECULAR-DYNAMICS; ENCAPSULATED C-60; NANOTUBES; SUPERCONDUCTIVITY; MECHANISM AB A fascinating structural transformation occurring inside single-walled carbon nanotubes (SWNTs) is the fullerene coalescence, which is responsible for forming stable zeppelinlike carbon molecules. We report in situ transmission electron microscope (TEM) observations revealing sequences of fullerene coalescence induced by electron irradiation on pristine nanotube peapods, together with extensive theoretical investigations of the microscopic mechanism underlying this process. TEM images indicate that the merging of fullerenes results in stable but corrugated tubules (5 to 7 Angstrom in diameter) confined within SWNTs. These observations have been confirmed using a combination of theoretical approaches based on molecular dynamics, empirical potentials, tight-binding methods, Monte Carlo techniques, and first principles calculations. We have fully elucidated the coalescence mechanism of fullerenes inside SWNTs under electron irradiation and thermal annealing. The process occurs via the polymerization Of C-60 molecules followed by surface reconstruction, which can be triggered either by the formation of vacancies (created under electron irradiation) or by surface-energy minimization activated by thermal annealing. These novel tubular forms of carbon contain hexagons, pentagons, heptagons, and octagons. The stability, electronic properties, and electron conductance of the novel tubules are strongly affected by the final geometry of the coalesced fullerene complex. The possibility of forming highly conducting and semiconducting tubular structures suggests new avenues in designing carbon nanowires with specific electronic characteristics. C1 CSIC, ICMAB, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. CSIC, CNM, Barcelona 08193, Spain. IPICYT, Adv Mat Dept, San Luis Potsosi 78210, Mexico. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Catholic Univ Louvain, PCPM & CERMIN, B-1348 Louvain, Belgium. RP Terrones, M (reprint author), CSIC, ICMAB, Campus Bellaterra, Oak Ridge, TN 37831 USA. EM mterrones@ipicyt.edu.mx RI Buongiorno Nardelli, Marco/C-9089-2009; Hernandez, Eduardo R. /B-1285-2008; Terrones, Mauricio/B-3829-2014; Rurali, Riccardo/D-3676-2011; Meunier, Vincent/F-9391-2010 OI Hernandez, Eduardo R. /0000-0002-1164-2856; Rurali, Riccardo/0000-0002-4086-4191; Meunier, Vincent/0000-0002-7013-179X NR 32 TC 140 Z9 141 U1 3 U2 41 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 AUG PY 2003 VL 3 IS 8 BP 1037 EP 1042 DI 10.1021/nl034283f 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 714BL UT WOS:000184892400010 ER PT J AU Kuykendall, T Pauzauskie, P Lee, SK Zhang, YF Goldberger, J Yang, PD AF Kuykendall, T Pauzauskie, P Lee, SK Zhang, YF Goldberger, J Yang, PD TI Metalorganic chemical vapor deposition route to GaN nanowires with triangular cross sections SO NANO LETTERS LA English DT Article ID GALLIUM NITRIDE NANOWIRES; CATALYTIC GROWTH; NANODEVICES AB High-quality gallium nitride nanowires have been synthesized via metal-initiated metalorganic chemical vapor deposition for the first time. Excellent substrate coverage was observed for wires prepared on silicon, c-plane, and a-plane sapphire substrates. The wires were formed via the vapor-liquid-solid mechanism with gold, iron, or nickel as growth initiators and were found to have widths of 15-200 nm. Transmission electron microscopy confirmed that the wires were single-crystalline and were oriented predominantly along the [210] or [110] direction. Wires growing along the [210] orientation were found to have triangular cross-sections. Transport measurements confirmed that the wires were n-type and had electron mobilities of similar to65 cm(2)/V.s. Photoluminescence measurements showed band edge emission at 3.35 eV (at 5 K), with a marked absence of low-energy emission from impurity defects. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Yang, PD (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Goldberger, Joshua/F-5484-2011; Pauzauskie, Peter/A-1316-2014; Goldberger, Joshua/N-8963-2016 OI Goldberger, Joshua/0000-0003-4284-604X; Goldberger, Joshua/0000-0003-4284-604X NR 12 TC 286 Z9 288 U1 4 U2 46 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 AUG PY 2003 VL 3 IS 8 BP 1063 EP 1066 DI 10.1021/nl034422t PG 4 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 714BL UT WOS:000184892400015 ER PT J AU Strano, MS Doorn, SK Haroz, EH Kittrell, C Hauge, RH Smalley, RE AF Strano, MS Doorn, SK Haroz, EH Kittrell, C Hauge, RH Smalley, RE TI Assignment of (n, m) Raman and optical features of metallic single-walled carbon nanotubes SO NANO LETTERS LA English DT Article ID DENSITY-OF-STATES; CHIRALITY DEPENDENCE; ROPES AB Raman spectroscopy performed between 565 and 627 nm and also between 458- and 514.5-nm laser excitation was used to map the lowest-energy van Hove singularities of metallic single-walled carbon nanotubes suspended in aqueous solution using sodium dodecyl sulfate. The interband transitions of distinct metallic nanotubes were observed directly and assigned using a correlation of the diameter and radial breathing mode (RBM) in the Raman spectrum. The results were extrapolated to all metallic nanotubes using a generalized scaling derived from the tight-binding formalism and were shown to be valid for describing the electronic structure of semiconducting nanotubes as well. The model results are compared using excitation profiles outside of the above-reported scan ranges with excellent agreement between observed and predicted profile widths and transition energies. C1 Univ Illinois, Dept Chem & Biomol Engn, Urbana, IL 61801 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Rice Univ, Dept Chem, Houston, TX 77005 USA. RP Strano, MS (reprint author), Univ Illinois, Dept Chem & Biomol Engn, Urbana, IL 61801 USA. RI Hauge, Robert/A-7008-2011; Zhou, Charlie/N-5376-2015 OI Hauge, Robert/0000-0002-3656-0152; NR 21 TC 210 Z9 213 U1 1 U2 47 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 AUG PY 2003 VL 3 IS 8 BP 1091 EP 1096 DI 10.1021/nl034196n 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 714BL UT WOS:000184892400021 ER PT J AU Allison, SW Gillies, GT Rondinone, AJ Cates, MR AF Allison, SW Gillies, GT Rondinone, AJ Cates, MR TI Nanoscale thermometry via the fluorescence of YAG : Ce phosphor particles: measurements from 7 to 77 degrees C SO NANOTECHNOLOGY LA English DT Article ID THERMOGRAPHIC PHOSPHORS; TEMPERATURE; INSTRUMENTATION; NANOCRYSTALS; STATES; MICRO AB The laser-induced fluorescence lifetime of 30 nm particles of YAG:Ce was measured as a function of temperature from 7 to 77 degreesC. The fluorescence decay lifetimes for the nanoparticles of this phosphor varied from; approximate to18 to 27 ns. i.e approximate to33% relative to the longest lifetime measured. This large variation in lifetime, coupled with the high signal strength that was observed, suggest that YAG:Ce nanoparticles will be useful thermographic phosphors. We describe the material and the apparatus used to characterize its fluorescence, present the results of measurements made over the range of temperatures tested and comment on some possible applications for this novel material. C1 Oak Ridge Natl Lab, Engn Technol Div, Oak Ridge, TN 37932 USA. Univ Virginia, Dept Mech & Aerosp Engn, Charlottesville, VA 22904 USA. Virginia Commonwealth Univ, Div Neurosurg, Richmond, VA 23298 USA. Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37932 USA. RP Allison, SW (reprint author), Oak Ridge Natl Lab, Engn Technol Div, POB 2008 MS6472, Oak Ridge, TN 37932 USA. RI Rondinone, Adam/F-6489-2013 OI Rondinone, Adam/0000-0003-0020-4612 NR 20 TC 56 Z9 57 U1 5 U2 35 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0957-4484 J9 NANOTECHNOLOGY JI Nanotechnology PD AUG PY 2003 VL 14 IS 8 BP 859 EP 863 AR PII S0957-4484(03)58006-0 DI 10.1088/0957-4484/14/8/304 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied SC Science & Technology - Other Topics; Materials Science; Physics GA 721AD UT WOS:000185294100013 ER PT J AU Parrinello, S Samper, E Krtolica, A Goldstein, J Melov, S Campisi, J AF Parrinello, S Samper, E Krtolica, A Goldstein, J Melov, S Campisi, J TI Oxygen sensitivity severely limits the replicative lifespan of murine fibroblasts SO NATURE CELL BIOLOGY LA English DT Article ID DEPENDENT PROTEIN-KINASE; MOUSE EMBRYO CELLS; TELOMERE LENGTH; CATALYTIC SUBUNIT; TUMOR-SUPPRESSOR; DNA; SENESCENCE; MICE; REPAIR; P19(ARF) AB Most mammalian cells do not divide indefinitely, owing to a process termed replicative senescence. In human cells, replicative senescence is caused by telomere shortening, but murine cells senesce despite having long stable telomeres'. Here, we show that the phenotypes of senescent human fibroblasts and mouse embryonic fibroblasts (MEFs) differ under standard culture conditions, which include 20% oxygen. MEFs did not senesce in physiological (3%) oxygen levels, but underwent a spontaneous event that allowed indefinite proliferation in 20% oxygen. The proliferation and cytogenetic profiles of DNA repair-deficient MEFs suggested that DNA damage limits MEF proliferation in 20% oxygen. Indeed, MEFs accumulated more DNA damage in 20% oxygen than 3% oxygen, and more damage than human fibroblasts in 20% oxygen. Our results identify oxygen sensitivity as a critical difference between mouse and human cells, explaining their proliferative differences in culture, and possibly their different rates 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. RP Campisi, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NCI NIH HHS [Z01 BC010658]; NIA NIH HHS [R01 AG018679, AG00266, AG17242, AG18679, P01 AG017242, T32 AG000266] NR 30 TC 624 Z9 640 U1 2 U2 33 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 1465-7392 J9 NAT CELL BIOL JI Nat. Cell Biol. PD AUG PY 2003 VL 5 IS 8 BP 741 EP 747 DI 10.1038/ncb1024 PG 7 WC Cell Biology SC Cell Biology GA 710NX UT WOS:000184687300016 PM 12855956 ER PT J AU Albertson, DG Collins, C McCormick, F Gray, JW AF Albertson, DG Collins, C McCormick, F Gray, JW TI Chromosome aberrations in solid tumors SO NATURE GENETICS LA English DT Review ID COMPARATIVE GENOMIC HYBRIDIZATION; IN-SITU HYBRIDIZATION; HUMAN BREAST-CANCER; MOLECULAR CYTOGENETIC ANALYSIS; GENE-EXPRESSION PATTERNS; GROWTH-FACTOR RECEPTOR; TELOMERASE ACTIVITY; OVARIAN-CANCER; CELL-CYCLE; MICROSATELLITE ALTERATIONS AB Chromosome aberrations in human solid tumors are hallmarks of gene deregulation and genome instability. This review summarizes current knowledge regarding aberrations, discusses their functional importance, suggests mechanisms by which aberrations may form during cancer progression and provides examples of clinical advances that have come from studies of chromosome aberrations. C1 Univ Calif San Francisco, Canc Res Inst, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Lab Med, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Microbiol & Immunol, San Francisco, CA 94143 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Albertson, DG (reprint author), Univ Calif San Francisco, Canc Res Inst, Box 0128, San Francisco, CA 94143 USA. NR 162 TC 461 Z9 472 U1 1 U2 30 PU NATURE PUBLISHING GROUP PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1061-4036 J9 NAT GENET JI Nature Genet. PD AUG PY 2003 VL 34 IS 4 BP 369 EP 376 DI 10.1038/ng1215 PG 8 WC Genetics & Heredity SC Genetics & Heredity GA 706TE UT WOS:000184470500013 PM 12923544 ER PT J AU Yu, H Li, JB Loomis, RA Wang, LW Buhro, WE AF Yu, H Li, JB Loomis, RA Wang, LW Buhro, WE TI Two- versus three-dimensional quantum confinement in indium phosphide wires and dots SO NATURE MATERIALS LA English DT Article ID LOW-DIMENSIONAL SYSTEMS; LIQUID-SOLID GROWTH; ELECTRONIC-STRUCTURE; NANOWIRES; NANOPARTICLES; ENERGY; SEMICONDUCTORS; NANOCRYSTALS; EXCITONS; EMISSION C1 Washington Univ, Dept Chem, St Louis, MO 63130 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. RP Wang, LW (reprint author), Washington Univ, Dept Chem, St Louis, MO 63130 USA. RI Buhro, William/A-7682-2009 NR 30 TC 268 Z9 271 U1 11 U2 80 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 AUG PY 2003 VL 2 IS 8 BP 517 EP 520 DI 10.1038/nmat942 PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 710NW UT WOS:000184687200009 PM 12872161 ER PT J AU Robb, VA Li, W Gascard, P Perry, A Mohandas, N Gutmann, DH AF Robb, VA Li, W Gascard, P Perry, A Mohandas, N Gutmann, DH TI Identification of a third Protein 4.1 tumor suppressor, Protein 4.1R, in meningioma pathogenesis SO NEUROBIOLOGY OF DISEASE LA English DT Article DE meningioma; brain tumor; merlin; schwannomin; Protein 4.1R; Protein 4.1B/DAL-1; CD44; tumor suppressor ID TYROSINE KINASE SUBSTRATE; NF2 GENE; SPORADIC MENINGIOMAS; ANAPLASTIC MENINGIOMAS; GROWTH-FACTOR; CLINICOPATHOLOGICAL SUBSETS; PROGNOSTIC IMPLICATIONS; AGGRESSIVE MENINGIOMAS; MALIGNANT MENINGIOMA; CYTOGENETIC ANALYSIS AB Meningiomas are common central nervous system tumors; however, the mechanisms underlying their pathogenesis are largely undefined. In this report, we demonstrate that a third Protein 4 1 family member, Protein 4.1R, functions as a meningioma tumor suppressor. We observed loss of Protein 4.1R expression in two meningioma cell lines (IOMM-Lee, CH157-MN) by Western blotting as well as in 6 of 15 sporadic meningiomas by immunohistochemistry and fluorescence in situ hybridization. In support of a meningioma tumor suppressor function, Protein 4.1R overexpression resulted in reduced IOMM-Lee and CH157-MN cell proliferation. Similar to the Protein 4.1B and merlin tumor suppressors, Protein 4.1R membrane localization increased significantly under conditions of growth arrest in vitro. Lastly, we show that Protein 4.1R interacted with a subset of merlin/Protein 4.1B interactors including CD44 and betaII-spectrin. Collectively, these results suggest that Protein 4.1R functions as an important tumor suppressor in the molecular pathogenesis of meningioma. (C) 2003 Elsevier Science (USA). All rights reserved. C1 Washington Univ, Sch Med, Dept Neurol, St Louis, MO 63110 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Dept Subcellular Struct, Berkeley, CA 94720 USA. Washington Univ, Sch Med, Dept Neuropathol, St Louis, MO 63110 USA. New York Blood Ctr, New York, NY 10021 USA. RP Gutmann, DH (reprint author), Washington Univ, Sch Med, Dept Neurol, Box 8111,660 S Euclid Ave, St Louis, MO 63110 USA. OI Perry, Arie/0000-0002-8300-7261 FU NCI NIH HHS [F32-CA097816]; NINDS NIH HHS [NS35848, NS41520] NR 71 TC 50 Z9 52 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 0969-9961 J9 NEUROBIOL DIS JI Neurobiol. Dis. PD AUG PY 2003 VL 13 IS 3 BP 191 EP 202 DI 10.1016/S0969-9961(03)00071-8 PG 12 WC Neurosciences SC Neurosciences & Neurology GA 708GT UT WOS:000184559400002 PM 12901833 ER PT J AU Ernst, T Chang, L Arnold, S AF Ernst, T Chang, L Arnold, S TI Increased glial metabolites predict increased working memory network activation in HIV brain injury SO NEUROIMAGE LA English DT Article DE functional MRI; MR spectroscopy; HIV; brain; metabolism ID AIDS DEMENTIA COMPLEX; MAGNETIC-RESONANCE SPECTROSCOPY; COGNITIVE MOTOR COMPLEX; PROTON MR SPECTROSCOPY; CENTRAL-NERVOUS-SYSTEM; NECROSIS-FACTOR-ALPHA; NEURONAL LOSS; ABSOLUTE QUANTITATION; N-ACETYLASPARTATE; ENERGY-METABOLISM AB Deficits in attention and working memory are common in human immuno deficiency virus type 1 (HIV-1)-infected patients, but the pathophysiology of these deficits is poorly understood. Modem neuroimaging techniques, such as proton magnetic resonance spectroscopy (H-1 MRS) and functional MRI (fMRI), can assess some of the processes underlying HIV brain injury. To evaluate the model that attentional deficits in early HIV brain disease are related to brain inflammation, H-1 MRS and fMRI were performed in 14 HIV-positive subjects [acquired immunodeficiency syndrome (AIDS) dementia complex stage I or less]. Increasing attentional load on three working memory tasks was assessed with fMRI, and the concentrations of brain metabolites were measured with H-1 MRS in the frontal gray and white matter, and basal ganglia. Metabolite concentrations were correlated with fMRI blood oxygenation level-dependent (BOLD) signals, using a random-effects linear regression model in SPM99. Several positive correlations were observed between the BOLD signal strength in the working memory network (posterior parietal cortex and lateral prefrontal cortex) and the concentrations of frontal white matter and basal ganglia metabolites that are predominant in glial cells (choline-containing compounds, myo-inositol, and total creatine). In contrast, BOLD signals in the working memory network were not correlated with the concentration of N-acetyl compounds, which are markers of neuronal viability, or with metabolite concentrations in the frontal gray matter. These findings are consistent with previous results that mild HIV brain injury is associated with increased glial activation without major involvement of neuronal abnormalities. We propose that the inflammatory glial abnormalities reduce the efficiency of neural processing, and necessitate compensatory increases in attention in patients, and associated BOLD signals, to perform a given task. The same mechanism may also contribute to cognitive dysfunction in other brain diseases that involve inflammation. (C) 2003 Elsevier Science (USA). All rights reserved. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Ernst, T (reprint author), Brookhaven Natl Lab, Dept Med, Bldg 490, Upton, NY 11973 USA. FU NCRR NIH HHS [M01 RR 00425]; NIDA NIH HHS [K20 DA 00280]; NIMH NIH HHS [R01 MH 61427]; NINDS NIH HHS [R01 NS 38834] NR 54 TC 51 Z9 53 U1 0 U2 4 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1053-8119 J9 NEUROIMAGE JI Neuroimage PD AUG PY 2003 VL 19 IS 4 BP 1686 EP 1693 DI 10.1016/S1053-8119(03)00232-5 PG 8 WC Neurosciences; Neuroimaging; Radiology, Nuclear Medicine & Medical Imaging SC Neurosciences & Neurology; Radiology, Nuclear Medicine & Medical Imaging GA 717GK UT WOS:000185079000038 PM 12948723 ER PT J AU Sills, A Deiters, S Eggleton, P Freitag, M Giersz, M Heggie, D Hurley, J Hut, P Ivanova, N Klessen, RS Kroupa, P Lombardi, JC McMillan, S Zwart, SP Zinnecker, H AF Sills, A Deiters, S Eggleton, P Freitag, M Giersz, M Heggie, D Hurley, J Hut, P Ivanova, N Klessen, RS Kroupa, P Lombardi, JC McMillan, S Zwart, SP Zinnecker, H TI MODEST-2: a summary SO NEW ASTRONOMY LA English DT Review DE methods : numerical; methods : N-body simulations; open clusters and associations : general; globular clusters : general; galaxy : center; galaxy : kinematics and dynamics ID MONTE-CARLO SIMULATIONS; INITIAL MASS FUNCTION; ORION NEBULA CLUSTER; SMOOTHED PARTICLE HYDRODYNAMICS; STELLAR COLLISION PRODUCTS; ANISOTROPIC GASEOUS MODELS; TURBULENT MOLECULAR CLOUDS; MULTIPLE STAR-FORMATION; SOLAR-TYPE STARS; T-TAURI STARS AB This is a summary paper of MODEST-2, a workshop held at the Astronomical Institute 'Anton Pannekoek' in Amsterdam, 16-17 December 2002. MODEST is a loose collaboration of people interested in Modelling DEnse STellar systems, particularly those interested in modelling these systems using all the available physics (stellar dynamics, stellar evolution, hydrodynamics and the interplay between the three) by defining interfaces between different codes. In this paper, we summarize: (1) the main advances in this endeavour since MODEST-1; (2) the main science goals which can be and should be addressed by these types of simulations; and (3) the most pressing theoretical and modelling advances that we identified. (C) 2003 Elsevier B.V. All rights reserved. C1 McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. Astron Rech Inst, D-69120 Heidelberg, Germany. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Polish Acad Sci, Nicholas Copernicus Astron Ctr, PL-00716 Warsaw, Poland. Univ Edinburgh, Sch Math, Edinburgh EH9 3JZ, Midlothian, Scotland. Amer Museum Nat Hist, Dept Astrophys, New York, NY 10024 USA. Inst Adv Study, Princeton, NJ 08540 USA. Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. Astrophys Inst Potsdam, D-14482 Potsdam, Germany. Univ Kiel, Inst Theoret Phys & Astrophys, D-24098 Kiel, Germany. Vassar Coll, Dept Phys & Astron, Poughkeepsie, NY 12604 USA. Drexel Univ, Dept Phys, Philadelphia, PA 19104 USA. Sterrenkundig Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands. RP Sills, A (reprint author), McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. EM asills@physics.mcmaster.ca; deiters@ari.uni-heidelberg.de; ppe@igpp.uclini.org; freitag@ari.uni-heidelberg.de; mig@camk.edu.pl; d.c.heggie@ed.ac.uk; jhurley@amnh.org; piet@ias.edu; nata@northwestern.edu; rklessen@aip.de; pavel@astrophysik.uni-kiel.de; lombardi@vassar.edu; steve@kepler.physics.drexel.edu; spz@science.uva.nl; hzinnecker@aip.de NR 160 TC 26 Z9 26 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1384-1076 J9 NEW ASTRON JI New Astron. PD AUG PY 2003 VL 8 IS 6 BP 605 EP 628 DI 10.1016/S1384-1076(03)00054-X PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 714BU UT WOS:000184893100010 ER PT J AU Dhankher, OP Shasti, NA Rosen, BP Fuhrmann, M Meagher, RB AF Dhankher, OP Shasti, NA Rosen, BP Fuhrmann, M Meagher, RB TI Increased cadmium tolerance and accumulation by plants expressing bacterial arsenate reductase SO NEW PHYTOLOGIST LA English DT Article DE arsenate reductase; ArsC; cadmium (Cd) tolerance; accumulation; phytoremediation; Arabidopsis; tobacco (Nicotiana tabacum) ID GAMMA-GLUTAMYLCYSTEINE SYNTHETASE; HEAVY-METAL DETOXIFICATION; ARABIDOPSIS-THALIANA; INDIAN MUSTARD; RESISTANCE; GENES; HYPERACCUMULATION; PHYTOREMEDIATION; DEFICIENT; NUTRITION AB Cadmium (Cd) is a major environmental pollutant that poses a serious threat to natural ecosystems. However, most initial attempts to engineer phytoremediation of Cd have not succeeded in developing sufficient Cd tolerance for vigorous plant growth. We found that the bacterial arsenate reductase gene (arsC ) provided Cd(II) resistance to Escherichia coli . When ArsC is overexpressed in tobacco (Nicotiana tabacum ) and Arabidopsis thaliana , both transgenic plant species showed significantly greater Cd tolerance than wild-type controls. At 50, 75, and 100 mum concentrations of Cd (II), the ArsC expressing transgenic lines grew bigger with broader leaves and longer roots than wild-type controls, which were stunted, turned yellow, flowered early, and often died. At the various Cd(II) concentrations, ArsC transgenic plants attained f. wt 2-3-fold higher than the wild-type plants and had roots significantly longer than wild-type plants. These transgenic plants also contained 30-50% higher Cd concentrations than wild-type plants. It is likely that the arsC gene directs Cd tolerance via the electrochemical reduction of Cd(II) to Cd(0). C1 Univ Georgia, Dept Genet, Athens, GA 30602 USA. Wayne State Univ, Dept Biochem & Mol Biol, Detroit, MI 48201 USA. Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. RP Meagher, RB (reprint author), Univ Georgia, Dept Genet, Athens, GA 30602 USA. RI Dhankher, Om Parkash/P-1880-2016 NR 42 TC 24 Z9 28 U1 0 U2 4 PU BLACKWELL PUBLISHING LTD PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND SN 0028-646X J9 NEW PHYTOL JI New Phytol. PD AUG PY 2003 VL 159 IS 2 BP 431 EP 441 DI 10.1046/j.1469-8137.2003.00827.x PG 11 WC Plant Sciences SC Plant Sciences GA 698ZW UT WOS:000184032200015 ER PT J AU Dauble, DD Hanrahan, TP Geist, DR Parsley, MJ AF Dauble, DD Hanrahan, TP Geist, DR Parsley, MJ TI Impacts of the Columbia River hydroelectric system on main-stem habitats of fall Chinook salmon SO NORTH AMERICAN JOURNAL OF FISHERIES MANAGEMENT LA English DT Article ID ECOSYSTEM PERSPECTIVE; SNAKE RIVER; CLASSIFICATION; POPULATIONS; STEELHEAD; ECOLOGY; CONTEXT; STREAMS; PATTERN; FLOW AB Salmonid habitats in main-stem reaches of the Columbia and Snake rivers have changed dramatically during the past 60 years because of hydroelectric development and operation. Only about 13% and 58% of riverine habitats in the Columbia and Snake rivers, respectively, remain. Most riverine habitat is found in the upper Snake River; however, it is upstream of Hells Canyon Dam and not accessible to anadromous salmonids. We determined that approximately 661 and 805 km of the Columbia and Snake rivers, respectively, were once used by fall chinook salmon Oncorhynchus tshawytscha for spawning. Fall chinook salmon currently use only about 85 km of the main-stem Columbia River and 163 kin of the main-stem Snake River for spawning. We used a geomorphic model to identify three river reaches downstream of present migration barriers with high potential for restoration of riverine processes: the Columbia River upstream of John Day Dam, the Columbia-Snake-Yakima River confluence, and the lower Snake River upstream of Little Goose Dam. Our analysis substantiated the assertion that historic spawning areas for fall chinook salmon occurred primarily within wide alluvial floodplains, which were once common in the mainstem Columbia and Snake rivers. These areas possessed more unconsolidated sediment and more bars and islands and had lower water surface slopes than did less extensively used areas. Because flows in the main stem are now highly regulated, the predevelopment alluvial river ecosystem is not expected to be restored simply by operational modification of one or more dams. Establishing more normative flow regimes-specifically, sustained peak flows for scouring-is essential to restoring the functional characteristics of existing, altered habitats. Restoring production of fall chinook salmon to any of these reaches also requires that population genetics and viability of potential seed populations (i.e., from tributaries, tailrace spawning areas, and hatcheries) be considered. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. US Geol Survey, Western Fisheries Res Ctr, Columbia River Res Lab, Cook, WA 98605 USA. RP Dauble, DD (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 68 TC 29 Z9 29 U1 5 U2 28 PU AMER FISHERIES SOC PI BETHESDA PA 5410 GROSVENOR LANE SUITE 110, BETHESDA, MD 20814-2199 USA SN 0275-5947 J9 N AM J FISH MANAGE JI North Am. J. Fish Manage. PD AUG PY 2003 VL 23 IS 3 BP 641 EP 659 DI 10.1577/M02-013 PG 19 WC Fisheries SC Fisheries GA 717VN UT WOS:000185111600001 ER PT J AU Nicolas, L Durin, M Koundy, V Mathet, E Bucalossi, A Eisert, P Sievers, J Humphries, L Smith, J Pistora, V Ikonen, K AF Nicolas, L Durin, M Koundy, V Mathet, E Bucalossi, A Eisert, P Sievers, J Humphries, L Smith, J Pistora, V Ikonen, K TI Results of benchmark calculations based on OLHF-1 test SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article AB The subject of this paper is to compare the results of the different calculations performed by the benchmark participants in the framework of the OECD Lower Head Failure (OLHF) program. The benchmark consists in the finite element (FE) calculation or in analytical calculations of the mechanical behavior of the OLHF-1 experiment. Seven participants from six countries and seven companies or organizations (AVN, VTT, GRS, UJV, SNL, IPSN and CEA) have performed the benchmark. The OLHF experiment program extends the NRC-sponsored SNL LHF program (NUREG/CR-5582) completed in 1998: these experiments where intended to simulate the thermal/mechanical loads to a 1/4.85-scale model of a reactor pressure vessel. The pressure vessel material (SA533B 1 steel) used in these experiments is prototypic of reactor PWR vessel material and has been well characterized by material property testing as part of this program. The OLHF tests advance the results of the previous testing program by examining the effects of large temperature differences across the vessel wall. Large temperature differences in excess of 150-400 K are more prototypic of accident conditions. Most of the participants performed 2-D axisymmetric analyses and doesn't study the crack opening. The global mechanical behaviour of OLHF-1 experiment is well represented but prediction of the maximum vertical displacement is not in good agreement with the experimental value. Failure time and location are in quite good agreement with experimental results but large discrepancies are observed on the mode of failure: creep or plasticity. To improve predictions, more investigation and work is needed on the choice of the failure criteria and failure mode. (C) 2003 Elsevier Science B.V. All rights reserved. C1 OECD, NEA, F-92130 Issy Les Moulineaux, France. CEA, F-91191 Gif Sur Yvette, France. ISRN, F-92262 Fontenay Aux Roses, France. AVN, Brussels, Belgium. GRS, D-50687 Cologne, Germany. Sandia Natl Labs, Albuquerque, NM 87185 USA. UJV, Rez 25068, Czech Republic. VTT Energy, Tekniikantie, Finland. RP Mathet, E (reprint author), OECD, NEA, F-92130 Issy Les Moulineaux, France. NR 16 TC 9 Z9 9 U1 0 U2 0 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 AUG PY 2003 VL 223 IS 3 BP 263 EP 277 DI 10.1016/S0029-5493(03)00064-5 PG 15 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 709NW UT WOS:000184632100003 ER PT J AU Petty, CC Prater, R Luce, TC Ellis, RA Harvey, RW Kinsey, JE Lao, LL Lohr, J Makowski, MA Wong, KL AF Petty, CC Prater, R Luce, TC Ellis, RA Harvey, RW Kinsey, JE Lao, LL Lohr, J Makowski, MA Wong, KL TI Effects of electron trapping and transport on electron cyclotron current drive on DIII-D SO NUCLEAR FUSION LA English DT Article ID NONINDUCTIVE CURRENT; CURRENT PROFILE; D TOKAMAK; ENHANCED CONFINEMENT; PLASMAS; WAVES; FIELD; EFFICIENCY; SPECTROSCOPY; OPERATION AB Recent experiments on the DIII-D tokamak have focused on determining the effect of trapped particles on the electron cyclotron current drive (ECCD) efficiency. The experimental ECCD efficiency increases as the deposition location is moved towards the inboard midplane or towards smaller minor radius for both co- and counter-injection; the ECCD efficiency also increases with increasing electron density and/or temperature. The experimental ECCD is compared to both the linear theory (TORAY-GA) as well as a quasilinear Fokker-Planck model (CQL3D) and is found to be in better agreement with the more complete Fokker-Planck calculation, especially when the rf power density and/or loop voltage exceed criterion for substantial nonlinear modification of the electron distribution function. The width of the measured ECCD profile is consistent with the theoretically expected width in the absence of radial transport for the current carrying electrons. C1 Gen Atom, San Diego, CA 92186 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. CompX, Del Mar, CA USA. Lehigh Univ, Bethlehem, PA 18015 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Petty, CC (reprint author), Gen Atom, POB 85608, San Diego, CA 92186 USA. NR 47 TC 30 Z9 30 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 AUG PY 2003 VL 43 IS 8 BP 700 EP 707 DI 10.1088/0029-5515/43/8/310 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 719AK UT WOS:000185180800010 ER PT J AU Gohil, P Kinsey, J Parail, V Litaudon, X Fukuda, T Hoang, T AF Gohil, P Kinsey, J Parail, V Litaudon, X Fukuda, T Hoang, T CA ITPA Grp Transport ITB Phys Int ITB Database Working Grp TI Increased understanding of the dynamics and transport in ITB plasmas from multi-machine comparisons SO NUCLEAR FUSION LA English DT Article ID SHEAR DISCHARGES; MAGNETIC SHEAR; ASPECT RATIO; TURBULENCE; TOKAMAKS; BARRIERS; MODEL AB Our understanding of the physics of internal transport barriers (ITBs) is being advanced by analysis and comparisons of experimental data from many different tokamaks worldwide. An international database consisting of scalar and two-dimensional profile data for ITB plasmas is being developed to determine the requirements for the formation and sustainment of ITBs and to perform tests of theory-based transport models in an effort to improve the predictive capability of the models. Analysis using the database indicates that: (a) the power required to form ITBs decreases with increased negative magnetic shear of the target plasma, and: (b) the E x B flow shear rate is close to the linear growth rate of the ion temperature gradient (ITG) modes at the time of barrier formation when compared for several fusion devices. Tests of several transport models (JETTO, Weiland model) using the two-dimensional profile data indicate that there is only limited agreement between the model predictions and the experimental results for the range of plasma conditions examined for the different devices (DIII-D, JET, JT-60U). Gyrokinetic stability analysis (using the GKS code) of the ITB discharges from these devices indicates that the ITG/TEM growth rates decrease with increased negative magnetic shear and that the E x B shear rate is comparable to the linear growth rates at the location of the ITB. C1 Gen Atom, San Diego, CA 92186 USA. Lehigh Univ, Bethlehem, PA 18015 USA. EFDA, JET, CSU, Culham Sci Ctr, Abingdon, Oxon, England. EURATOM, CEA Cadarache, St Paul Les Durance, France. JAERI, Naka Fus Res Estab, Naka, Ibaraki, Japan. UKAEA EURATOM Assoc, Culham Sci Ctr, Abingdon, Oxon, England. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. IV Kurchatov Atom Energy Inst, Moscow 123182, Russia. Ioffe Inst, St Petersburg, Russia. ITER, JWS, Naka, Ibaraki, Japan. MIT, Cambridge, MA 02139 USA. Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Natl Inst Fus Sci, Toki, Japan. Forschungszentrum Julich GmbH, EURATOM Assoc, Julich, Germany. Kyoto Univ, Kyoto, Japan. Chalmers Univ, Gothenburg, Sweden. EURATOM VR Assoc, Gothenburg, Sweden. EURATOM, ENEA Fus, Frascati, Italy. FOM Inst Plasmafis Rijnhuizen, Nieuwegein, Netherlands. Max Planck Inst Plasma Phys, EURATOM Assoc, D-85748 Garching, Germany. RP Gen Atom, POB 85608, San Diego, CA 92186 USA. EM gohil@fusion.gat.com RI Peeters, Arthur/A-1281-2009; lebedev, sergei/K-2379-2013; OI Greenwald, Martin/0000-0002-4438-729X; Unterberg, Bernhard/0000-0003-0866-957X NR 17 TC 15 Z9 16 U1 2 U2 2 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 AUG PY 2003 VL 43 IS 8 BP 708 EP 715 AR PII S0029-5515(03)65704-2 DI 10.1088/0029-5515/43/8/311 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 719AK UT WOS:000185180800011 ER PT J AU Yamada, H Murakami, S Yamazaki, K Kaneko, O Miyazawa, J Sakamoto, R Watanabe, KY Narihara, K Tanaka, K Sakakibara, S Osakabe, M Peterson, BJ Morita, S Ida, K Inagaki, S Masuzaki, S Morisaki, T Rewoldt, G Sugama, H Nakajima, N Cooper, WA Akiyama, T Ashikawa, N Emoto, M Funaba, H Goncharov, P Goto, M Idei, H Ikeda, K Isobe, M Kawahata, K Kawazome, H Khlopenkov, K Kobuchi, T Komori, A Kostrioukov, A Kubo, S Kumazawa, R Liang, Y Minami, T Muto, S Mutoh, T Nagayama, Y Nakamura, Y Nakanishi, H Narushima, Y Nishimura, K Noda, N Notake, T Nozato, H Ohdachi, S Ohyabu, N Oka, Y Ozaki, T Sagara, A Saida, T Saito, K Sasao, M Sato, K Sato, M Seki, T Shimozuma, T Shoji, M Suzuki, H Takeiri, Y Takeuchi, N Tamura, N Toi, K Tokuzawa, T Torii, Y Tsumori, K Watanabe, T Watari, T Xu, Y Yamada, I Yamamoto, S Yamamoto, T Yokoyama, M Yoshimura, Y Yoshinuma, M Mito, T Itoh, K Ohkubo, K Ohtake, I Satow, T Sudo, S Uda, T Matsuoka, K Motojima, O AF Yamada, H Murakami, S Yamazaki, K Kaneko, O Miyazawa, J Sakamoto, R Watanabe, KY Narihara, K Tanaka, K Sakakibara, S Osakabe, M Peterson, BJ Morita, S Ida, K Inagaki, S Masuzaki, S Morisaki, T Rewoldt, G Sugama, H Nakajima, N Cooper, WA Akiyama, T Ashikawa, N Emoto, M Funaba, H Goncharov, P Goto, M Idei, H Ikeda, K Isobe, M Kawahata, K Kawazome, H Khlopenkov, K Kobuchi, T Komori, A Kostrioukov, A Kubo, S Kumazawa, R Liang, Y Minami, T Muto, S Mutoh, T Nagayama, Y Nakamura, Y Nakanishi, H Narushima, Y Nishimura, K Noda, N Notake, T Nozato, H Ohdachi, S Ohyabu, N Oka, Y Ozaki, T Sagara, A Saida, T Saito, K Sasao, M Sato, K Sato, M Seki, T Shimozuma, T Shoji, M Suzuki, H Takeiri, Y Takeuchi, N Tamura, N Toi, K Tokuzawa, T Torii, Y Tsumori, K Watanabe, T Watari, T Xu, Y Yamada, I Yamamoto, S Yamamoto, T Yokoyama, M Yoshimura, Y Yoshinuma, M Mito, T Itoh, K Ohkubo, K Ohtake, I Satow, T Sudo, S Uda, T Matsuoka, K Motojima, O TI Impact of heat deposition profile on global confinement of NBI heated plasmas in the LHD SO NUCLEAR FUSION LA English DT Article ID LARGE HELICAL DEVICE; ENERGY CONFINEMENT; TRANSPORT; MODEL AB Energy confinement and heat transport of net-current-free NBI heated plasmas in the large helical device (LHD) are discussed with emphasis on density and power deposition profile dependences. Although the apparent density dependence of the energy confinement time has been demonstrated in a wide parameter range in LHD, the loss of this dependence has been observed in the high density regime under specific conditions. Broad heat deposition due to off-axis alignment and shallow penetration of neutral beams degrades the global energy confinement while the local heat transport maintains a clear temperature dependence, lying between Bohm and gyro-Bohm characteristics. The central heat deposition tends towards an intrinsic density dependence like tau(E) alpha ((n) over bar (e)/p)(0.6) from the state where density dependence is lost. The broadening of the temperature profile due to the broad heat deposition profile contrasts with the invariant property that has been observed widely as profile resilience or stiffness in tokamak experiments. The confinement improvement as a result of the inward shift of the magnetic axis is obvious in the core region, which emphasizes the improvement of transport because of the geometry being unfavourable for the central heating of NBI in this configuration. The edge pressure, clearly, does not depend on the magnetic axis position. Unlike a tokamak H-mode, the edge pressure is determined by transport and can be increased by increasing the heating power. C1 Natl Inst Fus Sci, Gifu 5095292, Japan. Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. Ecole Polytech Fed Lausanne, Ctr Rech Phys Plasmas, CH-1015 Lausanne, Switzerland. Tokyo Inst Technol, Nucl Reactors Res Lab, Tokyo 1528550, Japan. Grad Univ Adv Studies, Dept Fus Sci, Sch Math & Phys Sci, Hayama 2400193, Japan. Kyoto Univ, Grad Sch Energy Sci, Uji 6110011, Japan. Nagoya Univ, Dept Energy Engn & Sci, Nagoya, Aichi 4648603, Japan. Univ Tokyo, Grad Sch Frontier Sci, Tokyo 1130033, Japan. RP Natl Inst Fus Sci, Gifu 5095292, Japan. EM hyamada@lhd.nifs.ac.jp RI Nozato, Hideaki/C-9620-2011; Sakamoto, Ryuichi/E-7557-2013; Sakakibara, Satoru/E-7542-2013; Goncharov, Pavel/I-4288-2013; Murakami, Sadayoshi/A-2191-2016; Mito, Toshiyuki/E-7537-2013; Ida, Katsumi/E-4731-2016 OI Sakamoto, Ryuichi/0000-0002-4453-953X; Sakakibara, Satoru/0000-0002-3306-0531; Hideo, Sugama/0000-0001-5444-1758; Goncharov, Pavel/0000-0001-9226-1694; Murakami, Sadayoshi/0000-0002-2526-7137; Mito, Toshiyuki/0000-0002-1705-9039; Ida, Katsumi/0000-0002-0585-4561 NR 23 TC 26 Z9 26 U1 0 U2 2 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 AUG PY 2003 VL 43 IS 8 BP 749 EP 755 AR PII S0029-5515(03)66026-6 DI 10.1088/0029-5515/43/8/317 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 719AK UT WOS:000185180800017 ER PT J AU Holland, C Diamond, PH Champeaux, S Kim, E Gurcan, O Rosenbluth, MN Tynan, GR Crocker, N Nevins, W Candy, J AF Holland, C Diamond, PH Champeaux, S Kim, E Gurcan, O Rosenbluth, MN Tynan, GR Crocker, N Nevins, W Candy, J TI Investigations of the role of nonlinear couplings in structure formation and transport regulation: experiment, simulation, and theory SO NUCLEAR FUSION LA English DT Article ID DRIFT-WAVE TURBULENCE; GRADIENT-DRIVEN TURBULENCE; DIGITAL BISPECTRAL ANALYSIS; FLUID MODEL TURBULENCE; ZONAL FLOW GENERATION; E-X-B; TEMPERATURE-GRADIENT; EDGE TURBULENCE; TOKAMAK PLASMA; SHEAR FLOWS AB In this paper, we report on an integrated program of experimental, computational, and theoretical studies of sheared zonal flows and radially extended convective cells, with the aim of assessing the results of theory-experiment and theory-simulation comparisons. In particular, simulations are used as test beds for verifying analytical predictions (specifically locality and directionality of energy transfer) of nonlinear dynamics and to investigate the suitability of bispectral analysis for studying nonlinear couplings. Initial comparisons to experimental results are presented, and future experimental studies are motivated. We also present analytic and numerical work investigating the role of structures in transport. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Gen Atom, San Diego, CA 92186 USA. RP Holland, C (reprint author), Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RI Gurcan, Ozgur/A-1362-2013 OI Gurcan, Ozgur/0000-0002-2278-1544 NR 75 TC 22 Z9 22 U1 0 U2 3 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 AUG PY 2003 VL 43 IS 8 BP 761 EP 780 AR PII S0029-5515(03)66173-9 DI 10.1088/0029-5515/43/8/319 PG 20 WC Physics, Fluids & Plasmas SC Physics GA 719AK UT WOS:000185180800019 ER PT J AU Anulli, F Bagnasco, S Baldini, R Band, HR Bionta, R Brau, JE Brigljevic, V Buzzo, A Calcaterra, A Carpinelli, M Cartaro, T Cavallo, N Crosetti, G de Sangro, R De Nardo, G Eichenbaum, A Fabozzi, F Falciai, D Ferrarotto, F Ferroni, F Finocchiaro, G Forti, F Frey, R Gatto, C Grauges, E Iwasaki, M Johnson, JR Lange, DJ Lau, YP Lista, L Lovetere, M Lu, C Macri, M Moore, TB Morganti, S Neri, N Neal, H Palano, A Paoloni, E Paolucci, P Passaggio, S Pastore, F Patteri, P Peruzzi, I Piccolo, M Piccolo, D Piredda, G Robutti, E Roodman, A Santroni, A Sciacca, C Sinev, NB Strom, D Soha, A Tosi, S Va'vra, J Wisniewski, WJ Wright, DM Xie, Y Zallo, A AF Anulli, F Bagnasco, S Baldini, R Band, HR Bionta, R Brau, JE Brigljevic, V Buzzo, A Calcaterra, A Carpinelli, M Cartaro, T Cavallo, N Crosetti, G de Sangro, R De Nardo, G Eichenbaum, A Fabozzi, F Falciai, D Ferrarotto, F Ferroni, F Finocchiaro, G Forti, F Frey, R Gatto, C Grauges, E Iwasaki, M Johnson, JR Lange, DJ Lau, YP Lista, L Lovetere, M Lu, C Macri, M Moore, TB Morganti, S Neri, N Neal, H Palano, A Paoloni, E Paolucci, P Passaggio, S Pastore, F Patteri, P Peruzzi, I Piccolo, M Piccolo, D Piredda, G Robutti, E Roodman, A Santroni, A Sciacca, C Sinev, NB Strom, D Soha, A Tosi, S Va'vra, J Wisniewski, WJ Wright, DM Xie, Y Zallo, A TI Mechanisms affecting performance of the BaBar resistive plate chambers and searches for remediation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 6th International Workshop on Resistive Plate Chambers and Related Detectors CY NOV 26-27, 2001 CL COIMBRA, PORTUGAL SP FCT, Lab Instrumentacao & Fis Expt Particulas, Univ Coimbra, Fac Ciencias & Technol, Inst Superior Engenharia, Inst Politech Coimbra, A Silva Matos, Metalomecan SA, Inst Soldadura & Qualidade DE RPC remediation; linseed oil stalagmite; polymerization; oxygen treatment AB The BaBar experiment at PEPII relies on the instrumentation of the flux return (IFR) for both muon identification and K-L detection. The active detector is composed of resistive plate chambers (RPCs) operated in streamer mode. Since the start of operation the RPCs have suffered persistent efficiency deterioration and dark current increase problems. The "autopsy" of bad BaBar RPCs revealed that in many cases uncured linseed oil droplets had formed on the inner surface of the Bakelite plates, leading to current paths from oil "stalagmites" bridging the 2 turn gap. In this paper, a possible model of this "stalagmite" formation and its effect on the dark current and efficiency of RPC chambers is presented. Laboratory test results strongly support this model. Based upon this model we are searching for solutions to eliminate the unfavorable effect of the oil stalagmites. The lab tests show that the stalagmite resistivity increases dramatically if exposed to the air, an observation that points to a possible way to remedy the damage and increase the efficiency. We have seen that flowing an oxygen gas mixture into the chamber helps to polymerize the uncured linseed oil. Consequently, the resistivity of the bridged oil stalagmites increases, as does that of the oil coating on the frame edges and spacers, significantly reducing the RPC dark currents and low-efficiency regions. We have tested this idea on two chambers removed from BaBar because of their low efficiency and high dark current. These test results are reported in the paper, and two other remediation methods also mentioned. We continue to study this problem, and try to find new treatments with permanent improvement. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Princeton Univ, Joseph Henry Labs, Princeton, NJ 08544 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy. Ist Nazl Fis Nucl, I-16146 Genoa, Italy. Univ Wisconsin, Madison, WI 53706 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Oregon, Eugene, OR 97403 USA. Ist Nazl Fis Nucl, I-56010 Pisa, Italy. Univ Pisa, Scuola Normale Super Pisa, I-56010 Pisa, Italy. Univ Naples Federico II, Dipartimento Sci Fisiche, I-80126 Naples, Italy. Ist Nazl Fis Nucl, I-80126 Naples, Italy. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Yale Univ, New Haven, CT 06511 USA. Univ Bari, Dipartmento Fis, I-70126 Bari, Italy. Ist Nazl Fis Nucl, I-70126 Bari, Italy. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Lu, C (reprint author), Princeton Univ, Joseph Henry Labs, Princeton, NJ 08544 USA. RI Lo Vetere, Maurizio/J-5049-2012; Calcaterra, Alessandro/P-5260-2015; Frey, Raymond/E-2830-2016; Lista, Luca/C-5719-2008; Forti, Francesco/H-3035-2011; Neri, Nicola/G-3991-2012; Bagnasco, Stefano/J-4324-2012; Cavallo, Nicola/F-8913-2012 OI Lo Vetere, Maurizio/0000-0002-6520-4480; Calcaterra, Alessandro/0000-0003-2670-4826; Frey, Raymond/0000-0003-0341-2636; Paoloni, Eugenio/0000-0001-5969-8712; Carpinelli, Massimo/0000-0002-8205-930X; Forti, Francesco/0000-0001-6535-7965; Sciacca, Crisostomo/0000-0002-8412-4072; Neri, Nicola/0000-0002-6106-3756; NR 6 TC 15 Z9 15 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 AUG 1 PY 2003 VL 508 IS 1-2 BP 128 EP 132 DI 10.1016/S0168-9002(03)01292-0 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 708UH UT WOS:000184587500027 ER PT J AU Bringa, EM AF Bringa, EM TI Molecular dynamics simulations of Coulomb explosion SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 5th International Symposium on Swift Heavy Ions in Matter (SHIM 2002) CY MAY 19-23, 2002 CL GIARDINI NAXOS, ITALY DE Coulomb explosion; sputtering; tracks; molecular dynamics ID CHARGED-PARTICLE TRACKS; HEAVY-ION IRRADIATION; ENERGETIC IONS; GAS SOLIDS; MODEL; INSULATORS; PLASMA; RECOMBINATION; REGISTRATION; EXCITATION AB A swift ion creates a track of electronic excitations in the target material. A net repulsion inside the track can cause a "Coulomb explosion" (CE), which can lead to damage and sputtering of the material. Here we report results from molecular dynamics simulations of CEs for cylindrical tracks as a function of charge density and neutralization/quenching time, T. Screening by the free electrons is accounted for using a screened Coulomb potential for the interaction among charges. The yield exhibits a prompt component from the track core and a component from the heated region produced, which dominates at higher excitation density. For the cases studied, the number of atoms ejected per incident ion, i.e. the sputtering yield Y, is quadratic with charge density along the track as suggested by simple models. Y does not depend greatly on tau for tau greater than or similar to tau(D) (one Debye period), and even Y (tau = 0.2tau(D)) is still nearly 20% of the yield when there is no neutralization (tau --> infinity). The connections between 'CEs', thermal spikes and measurements of electronic sputtering are discussed. (C) 2003 Elsevier B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. RP Bringa, EM (reprint author), Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, MSTD L353,POB 808, Livermore, CA 94550 USA. RI Bringa, Eduardo/F-8918-2011 NR 44 TC 15 Z9 15 U1 1 U2 14 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 AUG PY 2003 VL 209 BP 1 EP 8 DI 10.1016/S0168-583X(02)02006-2 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 713YC UT WOS:000184884700002 ER PT J AU Clough, RL AF Clough, RL TI Review of the 5th IRaP conference SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Editorial Material C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Clough, RL (reprint author), Sandia Natl Labs, MS 0888, Albuquerque, NM 87185 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 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 AUG PY 2003 VL 208 BP 1 EP 3 DI 10.1016/S0168-583X(03)00629-3 PG 3 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 707LT UT WOS:000184512700002 ER PT J AU Maxwell, RS Balazs, B AF Maxwell, RS Balazs, B TI NMR measurements of residual dipolar couplings for lifetime assessments in gamma-irradiated silica-PDMS composite materials SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 5th International Symposium on Ionizing Radiation and Polymers (IRaP 2002) CY SEP 21-26, 2002 CL ST ADELE, CANADA SP Rech, Sci & Technol Quebec, Ecole Polytech Montreal, DSM DRECAM CEA/Saclay, IOM, IAEA Vienna, Grp COGETEFI, CTT Grp, GEX Corp, Nissin NHV Amer Inc, IBA, Promerus DE siloxanes; NMR; residual dipolar couplings; cross-linking; radiation ID DOUBLE-QUANTUM NMR; NUCLEAR-MAGNETIC-RESONANCE; CROSS-LINKED ELASTOMERS; STIMULATED ECHO; POLYMER MELTS; RUBBER; POLYDIMETHYLSILOXANE; SPECTROSCOPY; RELAXATION; DENSITY AB We have measured changes in H-1 NMR residual dipolar couplings, , and the mean squared fluctuations in the residual dipolar couplings, , associated with cross-link density changes in a complex silica-filled PDPS/PDMS d block copolymer composite material. The cross-links were induced by exposure of the composite material to gamma-radiation from a Co-60 source. We have detected H-1 NMR responses from polymer chains directly interacting with the silica and network polymer chains not directly interacting with the silica. The residual dipolar couplings change in a straightforward manner with radiation and chemically induced cross-linking of the polymer network. The strength of the filler-polymer interaction was seen to affect only the residual dipolar couplings and the transverse relaxation times and not directly the mean squared fluctuations of the residual dipolar couplings. Dipolar correlation effect NMR shows direct evidence for surface adsorbed species, however, and has measured changes in the amount of surface adsorption due to irradiation. The results suggest that siloxane polymer cross-linking was preceded by an initial disruption of the hydrogen bond interaction between the polymer backbone and the silica silanol groups at the polymer/silica interface and that noticeable radiation induced cross-linking then occurs at dosages above 100 kGray. (C) 2003 Elsevier B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. RP Maxwell, RS (reprint author), 7000 East Ave,L-091, Livermore, CA 94551 USA. NR 31 TC 11 Z9 11 U1 0 U2 5 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 AUG PY 2003 VL 208 BP 199 EP 203 DI 10.1016/S0168-583X(03)00642-6 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 707LT UT WOS:000184512700033 ER PT J AU Hennet, L Thiaudiere, D Landron, C Berar, JF Saboungi, ML Matzen, G Price, DL AF Hennet, L Thiaudiere, D Landron, C Berar, JF Saboungi, ML Matzen, G Price, DL TI Anomalous X-ray scattering on molten levitated samples SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE synchrotron; anomalous x-ray scattering; levitation ID RANGE ORDER; DIFFRACTION AB In a single diffraction measurement, on a multi-component high-temperature liquid, the measured S(Q) and G(r) are weighted averages of the partial functions for the different atom pairs, and different structural models can be consistent with the experimental data. In order to obtain more specific structural information, we have combined aerodynamic levitation and laser heating with the anomalous x-ray scattering technique to study the structure of liquid yttrium oxide at high temperature. The results are in good agreement with the previous experiments and computer simulations. This combination represents a powerful technique for obtaining reliable partial structure information in complex high-temperature liquid materials. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Ctr Rech Mat Haute Temp, F-45071 Orleans 2, France. CNRS, Cristallog Lab, F-38042 Grenoble 09, France. Ctr Rech Mat Divisee, F-45071 Orleans 2, France. Argonne Natl Lab, Argonne, IL 60439 USA. RP Ctr Rech Mat Haute Temp, 1d Ave Rech Sci, F-45071 Orleans 2, France. EM hennet@cnrs-orleans.fr RI HENNET, Louis/C-1711-2008; Price, David Long/A-8468-2013; Saboungi, Marie-Louise/C-5920-2013; d2am, beamline/I-6445-2015 OI HENNET, Louis/0000-0002-2992-4800; Saboungi, Marie-Louise/0000-0002-0607-4815; NR 20 TC 9 Z9 9 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD AUG PY 2003 VL 207 IS 4 BP 447 EP 452 DI 10.1016/S0168-583X(03)01077-2 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 699HQ UT WOS:000184051300009 ER PT J AU Jiang, W Shutthanandan, V Thevuthasan, S McCready, DE Weber, WJ AF Jiang, W Shutthanandan, V Thevuthasan, S McCready, DE Weber, WJ TI Oxygen analysis using energetic ion beams SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE nuclear reaction; reaction cross section; oxygen analysis ID MICROANALYSIS AB Using a thin amorphous layer of SiO2 (5.2 mug/cm(2)) on Si, cross sections for the nuclear reactions O-16(d,p(1))O-17, O-16(d,alpha)N-14 and O-16(alpha,alpha)O-16 at a laboratory angle of 150degrees are determined over energies ranging from 0.701 to 1.057 MeV for D+ ions and from 2.949 to 3.049 MeV for He+ ions. The results are plotted and tabulated as a function of ion energy, with typical uncertainties of 4% for the cross section data and of +/-5 keV for the resonance energy. An example for the analysis of atomic displacements on the O sublattice in a Au2+-irradiated SrTiO3 single crystal is given. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Jiang, W (reprint author), Pacific NW Natl Lab, MSIN K8-93,POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 12 TC 10 Z9 10 U1 0 U2 1 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 AUG PY 2003 VL 207 IS 4 BP 453 EP 461 DI 10.1016/S0168-583X(03)01123-6 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 699HQ UT WOS:000184051300010 ER PT J AU Tanaka, TJ Nowlen, SP Korsah, K Wood, RT Antonescu, CE AF Tanaka, TJ Nowlen, SP Korsah, K Wood, RT Antonescu, CE TI Impact of smoke exposure on digital instrumentation and control SO NUCLEAR TECHNOLOGY LA English DT Article; Proceedings Paper CT Topical Meeting of the American-Nuclear-Society CY NOV, 2000 CL WASHINGTON, D.C. SP Amer Nucl Soc DE smoke; qualification; digital circuits AB Smoke can cause interruptions and upsets in active electronics. Because nuclear power plants are replacing analog with digital instrumentation and control systems, qualification guidelines for new systems are being reviewed for severe environments such as smoke and electromagnetic interference. Active digital systems, individual components, and active circuits have been exposed to smoke in a program sponsored by the U.S. Nuclear Regulatory Commission. The circuits and systems were all monitored during the smoke exposure, indicating any immediate effects of the smoke. The results of previous smoke exposure studies have been reported in various publications. The major immediate effect of smoke has been to increase leakage currents and to cause momentary upsets and failures in digital systems. This paper presents new results from conformal coatings, memory chips, and hard drive tests. The best conformal coatings were found to be polyurethane, parylene, and acrylic (when applied by dipping). Conformal coatings can reduce smoke-induced leakage currents and protect against metal loss through corrosion. However conformal coatings are typically flammable, so they do increase material flammability. Some of the low-voltage biased memory chips failed during a combination of high smoke and high humidity. Typically, smoke along with heat and humidity is expected during fire, rather than smoke alone. Thus, due to high sensitivity of digital circuits to heat and humidity, it is hypothesized that the impact of smoke may be secondary. Low-voltage (3.3-V) static random-access memory (SRAMs) were found to be the most vulnerable to smoke. Higher bias voltages decrease the likelihood of failure. Erasable programmable read-only memory (EPROMs) and nonvolatile SRAMs were very smoke tolerant. Failures of the SRAMs occurred when two conditions were present: high density of smoke and high humidity. As the high humidity was present for only part of the test, the failures were intermittent. All of the chips that failed during the test recovered after enough venting. Hard disks were tested in severe environments but did not fail during the 2 h of monitoring. While the results of the tests documented in this report confirm that digital circuits can indeed be vulnerable to smoke, there is currently no practical, repeatable testing methodology, so it is not feasible to assess smoke susceptibility as part of environmental qualification. As a result, the most reasonable approach to minimizing smoke susceptibility is to employ design, implementation, and procedural practices that can reduce the possibility of smoke exposure and enhance smoke tolerance. Traditional approaches to mitigate its effects in digital safety instrumentation and control, such as redundancy, separation, defense in depth, as well as adherence to standards (e.g., the Institute of Electrical and Electronics Engineers' IEEE 384) and the Code of Federal Regulations Appendix R of 10 CFR 50, should continue to be applied. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. US Nucl Regulatory Commiss, Off Nucl Regulatory Res, Rockville, MD 20852 USA. RP Tanaka, TJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60526 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD AUG PY 2003 VL 143 IS 2 BP 152 EP 160 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 702YN UT WOS:000184252700006 ER PT J AU Wright, RE Fletcher, N Pearsall, RD Sidnev, VE Bickel, JH Vianello, A AF Wright, RE Fletcher, N Pearsall, RD Sidnev, VE Bickel, JH Vianello, A TI Upgrade of control and protection system of the Ignalina nuclear power plant Units 1 and 2 SO NUCLEAR TECHNOLOGY LA English DT Article; Proceedings Paper CT Topical Meeting of the American-Nuclear-Society CY NOV, 2000 CL WASHINGTON, D.C. SP Amer Nucl Soc DE RBMK nuclear reactor; nuclear safety; control and protection system AB The Ignalina nuclear power plant (NPP) Units 1 and 2 are Soviet-designed, RBMK (Reaktor Bolshoi Moschnosti Kipyashchiv), channelized,large power-type reactors. The original-design electrical capacity for each unit was 1500 MW. Unit I began operating in 1983, and Unit 2 was started up in 1987. In 1994, the government of Lithuania agreed to accept grant support for the Ignalina NPP Safety Improvement Program with funding supplied by the Nuclear Safety Account of the European Bank for Reconstruction and Development (EBRD). As conditions for receiving this funding, the Ignalina NPP agreed to prepare a comprehensive safety analysis report that would undergo independent peer review after it was issued. The EBRD Safety Panel oversaw preparation and review of the report. In 1996, the safety analysis report for Unit 1 was completed and delivered to the EBRD. Part of the analyses covered anticipated transients without scram (ATWS). The analysis showed that some ATWS scenarios could lead to unacceptable consequences in <1 min. The EBRD Safety Panel recommended to the government of Lithuania that the Ignalina NPP develop and implement a program of compensatory measures for the control and protection system before the unit would be allowed to return to operation following its 1998 maintenance outage. A compensatory control and protection system that would mitigate the unacceptable consequences was designed, procured, manufactured, tested, and installed. The project was funded by U.S. Department of Energy. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. US DOE, Washington, DC 20585 USA. Parsons, Reading, PA 19607 USA. Ignalina Nucl Power Plant, LT-4761 Visaginas, Lithuania. Scientech Inc, Boulder, CO 80303 USA. Invensys Foxboro C42 2C, Foxboro, MA 02035 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60526 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD AUG PY 2003 VL 143 IS 2 BP 241 EP 245 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 702YN UT WOS:000184252700014 ER PT J AU Ingber, MS Schmidt, CC Tanski, JA Phillips, J AF Ingber, MS Schmidt, CC Tanski, JA Phillips, J TI Boundary-element analysis of 3-D diffusion problems using a parallel domain decomposition method SO NUMERICAL HEAT TRANSFER PART B-FUNDAMENTALS LA English DT Article ID PARABOLIC DIFFERENTIAL-EQUATIONS; FLUID-DYNAMICS AB A parallel domain decomposition method is developed for the solution of three-dimensional diffusion problems. Within each subdomain, time is discretized using the generalized trapezoidal rule. The resulting modified Helmholtz equation is solved using the particular-solution boundary-element method. Interfacial conditions between subdomains are satisfied using a Schwarz Neumann-Neumann iteration scheme. Except for the first time step, when zero initial flux is assumed on all interfacial boundaries, the initial estimates for the interfacial flux are given from the converged solutions from the previous time step. This significantly reduces the number of iterations required to meet the convergence criterion. C1 Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. Los Alamos Natl Lab, Engn Sci & Applicat Div, Los Alamos, NM USA. RP Ingber, MS (reprint author), Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. NR 26 TC 9 Z9 9 U1 0 U2 3 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1040-7790 J9 NUMER HEAT TR B-FUND JI Numer Heat Tranf. B-Fundam. PD AUG PY 2003 VL 44 IS 2 BP 145 EP 164 DI 10.1080/10407790390200143 PG 20 WC Thermodynamics; Mechanics SC Thermodynamics; Mechanics GA 708FQ UT WOS:000184556900003 ER PT J AU Norby, RJ Sholtis, JD Gunderson, CA Jawdy, SS AF Norby, RJ Sholtis, JD Gunderson, CA Jawdy, SS TI Leaf dynamics of a deciduous forest canopy: no response to elevated CO2 SO OECOLOGIA LA English DT Article DE absorbed PAR; free-air CO2 enrichment; leaf area index; light-use efficiency; Liquidambar styraciflua ID LIGHT-USE EFFICIENCY; ATMOSPHERIC CARBON-DIOXIDE; AREA INDEX; PRIMARY PRODUCTIVITY; LIQUIDAMBAR STYRACIFLUA; NITROGEN CONCENTRATION; SWEETGUM STAND; ENRICHMENT; GROWTH; TREES AB Leaf area index (LAI) and its seasonal dynamics are key determinants of terrestrial productivity and, therefore, of the response of ecosystems to a rising atmospheric CO2 concentration. Despite the central importance of LAI, there is very little evidence from which to assess how forest LAI will respond to increasing [CO2]. We assessed LAI and related leaf indices of a closed-canopy deciduous forest for 4 years in 25-m-diameter plots that were exposed to ambient or elevated CO2 (542 ppm) in a free-air CO2 enrichment (FACE) experiment. LAI of this Liquidambar styraciflua (sweetgum) stand was about 6 and was relatively constant year-to-year, including the 2 years prior to the onset of CO2 treatment. LAI throughout the 1999-2002 growing seasons was assessed through a combination of data on photosynthetically active radiation (PAR) transmittance, mass of litter collected in traps, and leaf mass per unit area (LMA). There was no effect of [CO2] on any expression of leaf area, including peak LAI, average LAI, or leaf area duration. Canopy mass and LMA, however, were significantly increased by CO2 enrichment. The hypothesized connection between light compensation point (LCP) and LAI was rejected because LCP was reduced by [CO2] enrichment only in leaves under full sun, but not in shaded leaves. Data on PAR interception also permitted calculation of absorbed PAR (APAR) and light use efficiency (LUE), which are key parameters connecting satellite assessments of terrestrial productivity with ecosystem models of future productivity. There was no effect of [CO2] on APAR, and the observed increase in net primary productivity in elevated [CO2] was ascribed to an increase in LUE, which ranged from 1.4 to 2.4 g MJ(-1). The current evidence seems convincing that LAI of non-expanding forest stands will not be different in a future CO2-enriched atmosphere and that increases in LUE and productivity in elevated [CO2] are driven primarily by functional responses rather than by structural changes. Ecosystem or regional models that incorporate feedbacks on resource use through LAI should not assume that LAI will increase with CO2 enrichment of the atmosphere. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Texas Tech Univ, Lubbock, TX 79409 USA. RP Norby, RJ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Norby, Richard/C-1773-2012 OI Norby, Richard/0000-0002-0238-9828 NR 54 TC 68 Z9 72 U1 3 U2 20 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0029-8549 J9 OECOLOGIA JI Oecologia PD AUG PY 2003 VL 136 IS 4 BP 574 EP 584 DI 10.1007/s00442-003-1296-2 PG 11 WC Ecology SC Environmental Sciences & Ecology GA 721MX UT WOS:000185321100012 PM 12811536 ER PT J AU DeVault, TL Rhodes, OE Shivik, JA AF DeVault, TL Rhodes, OE Shivik, JA TI Scavenging by vertebrates: behavioral, ecological, and evolutionary perspectives on an important energy transfer pathway in terrestrial ecosystems SO OIKOS LA English DT Review ID TURKEY VULTURES; NATIONAL-PARK; AGRICULTURAL FIELDS; SONGBIRD CARCASSES; BURYING BEETLES; EATING CARRION; SMALL MAMMALS; WINTER DIETS; PREDATION; POPULATION AB Carrion use by terrestrial vertebrates is much more prevalent than conventional theory implies, and, rather than a curiosity of animal behavior, is a key ecological process that must be accounted for. Human aversion to rotted substances and difficulties associated with identifying scavenged material in studies of food habits have contributed to the relative lack of information concerning scavenging behavior in vertebrates. Several lines of evidence, however, suggest that carrion resources are more extensively used by vertebrates than has been widely assumed: 1) a substantial number of animals die from causes other than predation and become available to scavengers, 2) a wide variety of vertebrate scavengers, rather than microbes or arthropods, consume most available carcasses, and 3) intense competition exists between vertebrate scavengers and decomposers, especially in warm climates. Although vultures are best adapted to use carrion, nearly all vertebrate predators are also scavengers to some extent. The costs and benefits associated with carrion use influences the evolution of scavenging behavior in vertebrates, resulting in a continuum of facultative scavengers that use carrion to varying degrees. The realized usage of carrion by a vertebrate species is influenced by the speed and efficiency with which it forages, its visual and olfactory abilities, and its capacity for detoxifying products of decomposition. A deeper understanding of carrion use by facultative scavengers will improve our knowledge of community and ecosystem processes, especially the flow of energy through food webs. C1 Purdue Univ, Dept Forestry & Nat Resources, W Lafayette, IN 47907 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. Utah State Univ, Natl Wildlife Res Ctr, Logan, UT 84322 USA. RP DeVault, TL (reprint author), Purdue Univ, Dept Forestry & Nat Resources, W Lafayette, IN 47907 USA. EM tdevatdt@fhr.purdue.edu NR 96 TC 182 Z9 194 U1 9 U2 120 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0030-1299 EI 1600-0706 J9 OIKOS JI Oikos PD AUG PY 2003 VL 102 IS 2 BP 225 EP 234 DI 10.1034/j.1600-0706.2003.12378.x PG 10 WC Ecology SC Environmental Sciences & Ecology GA 704CA UT WOS:000184319100001 ER PT J AU Martinez, A Doerry, AW Jamshidi, M Bickel, D AF Martinez, A Doerry, AW Jamshidi, M Bickel, D TI Coherent data alignment and baseline calibration for improved two-pass interferometric synthetic aperture radar SO OPTICAL ENGINEERING LA English DT Article DE interferometric synthetic aperture radar; two-pass interferometric synthetic aperture radar; improved height estimation; coherent data alignment; baseline estimation; baseline calibration ID ACCURACY AB Currently, two principal operation modes are utilized by interferometric synthetic aperture radar (IFSAR) systems for data collection. The first mode is a one-antenna, two-pass IFSAR operation mode, where the aircraft platform possesses a single antenna and flies by the scene of interest twice collecting data. The two-antenna, one-pass IFSAR operation mode is the second mode, in which the aircraft platform possesses two antennas and flies by the scene of interest once while collecting data. Each one of these IFSAR operation modes possesses certain strengths and weaknesses. The one-antenna, two-pass mode allows for large baselines but suffers from imprecise knowledge of the baseline length, and consequently does not possess accurate target height scaling. Alternatively, the two-antenna, one-pass mode allows for precise knowledge of baseline length, but often at the expense of a limited baseline length, and consequently suffers from increased height noise. We describe an innovative IFSAR operation mode for overcoming these weaknesses by combining the two current IFSAR operation modes into a new two-antenna, two-pass IFSAR operation mode. By accurately estimating the antenna baseline between the two flight passes from the data itself, target height scaling accuracies are improved to the equivalent of a two-antenna, one-pass IFSAR system with the height-noise performance commensurate with the larger baseline. This, in turn, allows for more accurate information about target ground position locations and heights. (C) 2003 Society of Photo-Optical Instrumentation Engineers. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Ctr Autonomous Control, Dept Elect & Comp Engn, Albuquerque, NM 87131 USA. RP Martinez, A (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 25 TC 0 Z9 0 U1 1 U2 2 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD AUG PY 2003 VL 42 IS 8 BP 2427 EP 2438 DI 10.1117/1.1586705 PG 12 WC Optics SC Optics GA 709ZN UT WOS:000184656600040 ER PT J AU Yao, XC Castro, A AF Yao, XC Castro, A TI Optical trapping microfabrication with electrophoretic ally delivered particles inside glass capillaries SO OPTICS LETTERS LA English DT Article ID TWEEZERS; ARRAYS; FORCE AB We have developed a new technique for rapid microfabrication that uses electrophoretically delivered particles and an optical trap. The material particles, micrometer- and nanometer-sized polystyrene beads in aqueous solution, are continuously delivered to an optical trap by means of the electrophoretic effect inside glass capillaries or similar microstructures. The optical trap is used to manipulate and deposit the polystyrene beads onto a substrate. The continuous, on-demand delivery of particles allows for microfabrication in two and three dimensions with high speed and high efficiency and without material waste. This new technique has many potential applications in microelectronics and biotechnology. (C) 2003 Optical Society of America. C1 Los Alamos Natl Lab, Biophys Grp, Los Alamos, NM 87545 USA. RP Yao, XC (reprint author), Los Alamos Natl Lab, Biophys Grp, MS-D454, Los Alamos, NM 87545 USA. NR 16 TC 6 Z9 7 U1 0 U2 7 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 AUG 1 PY 2003 VL 28 IS 15 BP 1335 EP 1337 DI 10.1364/OL.28.001335 PG 3 WC Optics SC Optics GA 702ZZ UT WOS:000184256400015 PM 12906081 ER PT J AU Lee, SJ Usmani, KA Chanas, B Ghanayem, B Xi, T Hodgson, E Mohrenweiser, HW Goldstein, JA AF Lee, SJ Usmani, KA Chanas, B Ghanayem, B Xi, T Hodgson, E Mohrenweiser, HW Goldstein, JA TI Genetic findings and functional studies of human CYP3A5 single nucleotide polymorphisms in different ethnic groups SO PHARMACOGENETICS LA English DT Article DE CYP3A5; CYP3A5 polymorphisms; human; drug metabolism; SNP; cDNA expression system ID OXIDATIVE DRUG-METABOLISM; HUMAN-LIVER; ESCHERICHIA-COLI; EXPRESSION; IDENTIFICATION; PURIFICATION; VARIANTS; SEQUENCE; CANCER; FORM AB Objectives Genetic polymorphisms of cytochromes P450 (CYPs) are a principal reason for inter-individual variations in the metabolism of therapeutic drugs and environmental chemicals in humans. The present study identifies 34 single nucleotide polymorphisms (SNPs) of CYP3A5 including 27 previously unidentified SNPs by direct sequencing of the exons, intron-exon junctions and 5'-upstream region of CYP3A5 from 92 racially diverse individuals (24 Caucasians, 24 Africans, 24 Asians, and 20 individuals of unknown racial origin). Results Four new CYP3A5 SNPs produced coding changes: R28C, L82R, A337T, and F446S. CYP3A5 R28C occurred in African populations (allelic frequency of 4%). CYP3A5 A337T occurred in Asians (2% allelic frequency), CYP3A5 L82R (occurred in the racially unidentified group) and CYP3A5 F446S (identified in Caucasians with a 2% allelic frequency) were on an allele containing the splice change g.6986A>G known as CYP3A5*3. The newly identified allelic proteins were constructed by site-directed mutagenesis, expressed in Escherichia coli and purified. CYP3A5 L82R was expressed only as denatured CYP420, suggesting it may be unstable. CYP3A5*1 exhibited the highest maximal clearance for testosterone followed by CYP3A5 A337T>CYP3A5 R28C CYP3A5 F446S. CYP3A5*1 exhibited a higher V-max for nifedipine oxidation than CYP3A5 A337T>CYP3A5 R28Cmuch greater thanCYP3A5 F446S. CYP3A5 A337T and CYP3A5 R28C exhibited a 42-64% lower V-max for nifedipine oxidation than CYP3A5*1. CYP3A5 F446S exhibited a >95% decrease in the intrinsic clearance for both 6beta-hydroxytestosterone and nifedipine oxidation. Conclusion This study identifies four new potentially defective coding alleles. CYP3A5 F446S is predicted to be more catalytically defective than the splice change alone. (C) 2003 Lippincott Williams Wilkins. C1 NIEHS, Human Metab Sect, NIH, Res Triangle Pk, NC 27709 USA. NIEHS, Metab Exposure Markers Grp, Lab Pharmacol & Chem, NIH, Res Triangle Pk, NC 27709 USA. N Carolina State Univ, Dept Environm & Mol Toxicol, Raleigh, NC 27695 USA. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Goldstein, JA (reprint author), NIEHS, Human Metab Sect, NIH, POB 12233,A3-02, Res Triangle Pk, NC 27709 USA. RI Goldstein, Joyce/A-6681-2012 FU NIEHS NIH HHS [ES-8054-05] NR 47 TC 103 Z9 111 U1 0 U2 3 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0960-314X J9 PHARMACOGENETICS JI Pharmacogenetics PD AUG PY 2003 VL 13 IS 8 BP 461 EP 472 DI 10.1097/01.fpc.0000054117.14659.ac PG 12 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Pharmacology & Pharmacy SC Biotechnology & Applied Microbiology; Genetics & Heredity; Pharmacology & Pharmacy GA 714JY UT WOS:000184911500004 PM 12893984 ER PT J AU Schuh, CA Argon, AS Nieh, TG Wadsworth, J AF Schuh, CA Argon, AS Nieh, TG Wadsworth, J TI The transition from localized to homogeneous plasticity during nanoindentation of an amorphous metal SO PHILOSOPHICAL MAGAZINE LA English DT Article ID SERRATED FLOW; HIGH-PRESSURE; SHEAR BANDS; BUBBLE RAFT; STRAIN-RATE; THIN-FILMS; GLASS; DEFORMATION; ALLOY; INDENTATION AB Using nanoindentation, we examine the fundamental nature of plasticity in a bulk amorphous metal. We find that the mechanics of plasticity depend strongly on the indentation loading rate, with low rates promoting discretization of plasticity into rapid bursts. For sufficiently slow indentations, we find that plastic deformation becomes completely discretized in a series of isolated yielding events. As the loading rate is increased, a transition from discrete to continuous yielding is observed. These results are fundamentally different from the classical expectations for metallic glasses, in which the transition from discrete to continuous yielding occurs upon a decrease in deformation rate. The present experimental results are analysed with reference to the theoretical ideal-plastic strain field beneath an indenter and rationalized on the basis of mechanistic models of glass plasticity. C1 MIT, Cambridge, MA 02139 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Battelle Mem Inst, Columbus, OH 43201 USA. RP Schuh, CA (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Schuh, Christopher/C-7947-2009; Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 43 TC 81 Z9 86 U1 0 U2 27 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1478-6443 J9 PHILOS MAG JI Philos. Mag. PD AUG 1 PY 2003 VL 83 IS 22 BP 2585 EP 2597 DI 10.1080/1478643031000118012 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 705MR UT WOS:000184399300004 ER PT J AU Watanabe, S Hoshino, M Koike, T Suda, T Ohnuki, S Takahashi, H Lam, NQ AF Watanabe, S Hoshino, M Koike, T Suda, T Ohnuki, S Takahashi, H Lam, NQ TI Temporal fluctuation and its power law in the crystalline-to-glass transition during electron irradiation SO PHILOSOPHICAL MAGAZINE LA English DT Article ID RADIATION-INDUCED AMORPHIZATION; STRUCTURAL FLUCTUATIONS; SUPERCOOLED LIQUIDS; NOISE; TRANSFORMATION; SOLIDS AB Temporal nanostructural fluctuations brought about by transient metastable atom-cluster formation during radiation-induced amorphizing transformation in the intermetallic compound NiTi, observed using a combination of high-resolution high-voltage electron microscopy and molecular dynamics simulation, were characterized in terms of power-law responses of non-equilibrium energy-dissipative systems. Within the framework of the multi-Lorentzian picture, the resultant power law also describes the multirelaxation time (i.e. cluster lifetime) distribution. In addition, a unified relation for the autocorrelation functions for such fluctuation phenomena is discussed. C1 Hokkaido Univ, Grad Sch Engn, Div Mat Sci, Kita Ku, Sapporo, Hokkaido 0608628, Japan. Hokkaido Univ, Ctr Adv Res Energy Technol, Kita Ku, Sapporo, Hokkaido 0608628, Japan. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Watanabe, S (reprint author), Hokkaido Univ, Grad Sch Engn, Div Mat Sci, Kita Ku, Kita 13,Nishi 8, Sapporo, Hokkaido 0608628, Japan. RI seiichi, watanabe/E-2622-2012 NR 29 TC 8 Z9 8 U1 1 U2 2 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1478-6443 J9 PHILOS MAG JI Philos. Mag. PD AUG 1 PY 2003 VL 83 IS 22 BP 2599 EP 2619 DI 10.1080/1478643031000120280 PG 21 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 705MR UT WOS:000184399300005 ER PT J AU Harms, U Schwarz, RB Shen, TD AF Harms, U Schwarz, RB Shen, TD TI Crystallization kinetics in small volumes of undercooled liquid SO PHILOSOPHICAL MAGAZINE LETTERS LA English DT Article ID NI-P ALLOY; NUCLEATION; BEHAVIOR; GROWTH; GLASS AB We demonstrate that, under specific experimental conditions (isothermal crystallization from a single nucleation event in nearly spherical specimens), differential scanning calorimetry data can be used to deduce the velocity of a crystallization front in undercooled liquids. For Pd43.2Cu28Ni8.8P20 alloy and 683 K < T < 700 K, the growth velocity is approximately 4.3 x 10(13) (m s(-1)) exp (-2.7 eV/kT). C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Schwarz, RB (reprint author), Los Alamos Natl Lab, Div Mat Sci & Technol, MST-8,Mail Stop G755, Los Alamos, NM 87545 USA. NR 8 TC 2 Z9 2 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0950-0839 J9 PHIL MAG LETT JI Philos. Mag. Lett. PD AUG PY 2003 VL 83 IS 8 BP 503 EP 509 DI 10.1080/095008303/000119181 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 708PC UT WOS:000184576200005 ER PT J AU Laible, PD Morris, ZS Thurnauer, MC Schiffer, M Hanson, DK AF Laible, PD Morris, ZS Thurnauer, MC Schiffer, M Hanson, DK TI Inter- and intraspecific variation in excited-state triplet energy transfer rates in reaction centers of photosynthetic bacteria SO PHOTOCHEMISTRY AND PHOTOBIOLOGY LA English DT Article ID PRIMARY CHARGE SEPARATION; PRIMARY ELECTRON-TRANSFER; DETECTED MAGNETIC-RESONANCE; REACTION-CENTER MUTANTS; TIME-RESOLVED EPR; RHODOBACTER-SPHAEROIDES; RHODOPSEUDOMONAS-SPHAEROIDES; BACTERIOCHLOROPHYLL TRIPLET; PRIMARY DONOR; M-SUBUNIT AB In protein-cofactor reaction center (RC) complexes of purple photosynthetic bacteria, the major role of the bound carotenoid (C) is to quench the triplet state formed on the primary electron donor (P) before its sensitization of the excited singlet state of molecular oxygen from its ground triplet state. This triplet energy is transferred from P to C via the bacteriochlorophyll monomer B-B. Using time-resolved electron paramagnetic resonance (TREPR), we have examined the temperature dependence of the rates of this triplet energy transfer reaction in the RC of three wild-type species of purple nonsulfur bacteria. Species-specific differences in the rate of transfer were observed. Wild-type Rhodobacter capsulatus RCs were less efficient at the triplet transfer reaction than Rhodobacter sphaeroides RCs, but were more efficient than Rhodospirillum rubrum RCs. In addition, RCs from three mutant strains of R. capsulatus carrying substitutions of amino acids near P and BB were examined. Two of the mutant RCs showed decreased triplet transfer rates compared with wild-type RCs, whereas one of the mutant RCs demonstrated a slight increase in triplet transfer rate at low temperatures. The results show that site-specific changes within the RC of R. capsulatus can mimic interspecies differences in the rates of triplet energy transfer. This application of TREPR was instrumental in defining critical energetic and coupling factors that dictate the efficiency of this photoprotective process. C1 Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL USA. RP Laible, PD (reprint author), Argonne Natl Lab, Biosci Div, 9700 S Cass Ave,Bldg 202, Argonne, IL 60439 USA. EM laible@anl.gov OI Morris, Zachary/0000-0001-5558-3547 NR 69 TC 6 Z9 6 U1 0 U2 3 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0031-8655 EI 1751-1097 J9 PHOTOCHEM PHOTOBIOL JI Photochem. Photobiol. PD AUG PY 2003 VL 78 IS 2 BP 114 EP 123 DI 10.1562/0031-8655(2003)078<0114:IAIVIE>2.0.CO;2 PG 10 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 711ED UT WOS:000184725900003 PM 12945578 ER PT J AU Pynn, R Fitzsimmons, MR Fritzsche, H Major, J Rekveldt, MT AF Pynn, R Fitzsimmons, MR Fritzsche, H Major, J Rekveldt, MT TI Does beam divergence matter for neutron reflectometry? SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CALIFORNIA DE neutron scattering; neutron reflectometry; neutron spin echo ID SPIN-ECHO; LARMOR PRECESSION; MAGNETIZED FOILS; SCATTERING; DIFFRACTION; RESOLUTION; INSTRUMENT AB In this paper, we describe a method that uses Larmor precession of a neutron's spin to encode information about the direction of the neutron's path. We show that neutron spin echo (NSE) may be used to separate specular and diffuse reflection from the surface of a sample and to obtain information about the in-plane structure of thin films or interfaces. In the implementation discussed here, thin magnetic films of permalloy deposited on silicon substrates are used as Larmor precession devices that are both compact and well-defined geometrically and magnetically. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Hahn Meitner Inst Berlin GmbH, D-14109 Berlin, Germany. Max Planck Inst Met Res, D-70569 Stuttgart, Germany. Delft Univ Technol, Interfac Reactor Inst, NL-2629 JB Delft, Netherlands. RP Pynn, R (reprint author), Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. RI Lujan Center, LANL/G-4896-2012; OI Fritzsche, Helmut/0000-0001-5288-8302 NR 10 TC 2 Z9 2 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD AUG PY 2003 VL 336 IS 1-2 BP 1 EP 7 DI 10.1016/S0921-4526(03)00259-X PG 7 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600002 ER PT J AU Ankner, JF Brennan, S Kortright, JB AF Ankner, JF Brennan, S Kortright, JB TI Proceedings of the Seventh Iinternational Conference on Surface X-ray and Neutron Scattering - SXNS-7 - Lake Tahoe, CA, USA 23-27 September 2002 - Preface SO PHYSICA B-CONDENSED MATTER LA English DT Editorial Material C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ankner, JF (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. OI Ankner, John/0000-0002-6737-5718 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 0921-4526 J9 PHYSICA B JI Physica B PD AUG PY 2003 VL 336 IS 1-2 BP VII EP VII DI 10.1016/S0921-4526(03)00293-X PG 1 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600001 ER PT J AU Major, J Dosch, H Felcher, GP Habicht, K Keller, T Velthuis, SGET Vorobiev, A Wahl, M AF Major, J Dosch, H Felcher, GP Habicht, K Keller, T Velthuis, SGET Vorobiev, A Wahl, M TI Combining of neutron spin echo and reflectivity: a new technique for probing surface and interface order SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CALIFORNIA DE neutron reflectivity; grazing incidence diffuse scattering; neutron spin echo; SERGIS; neutron resonance spin echo; NRSE ID GRAZING-INCIDENCE; MAGNETIZED FOILS; SCATTERING; SPECTROMETRY AB The recently proposed spin-echo resolved grazing-incidence scattering (SERGIS) uses the well-known neutron spin echo effect for encoding the momentum transfer in reflectometry. By the application of tilted magnetic-field borders, SERGIS measures the scattering angle in grazing incidence experiments in absence of any geometrical beam-defining tool, such as slits. The main difficulty in such set-ups is the realization of geometrically flat field borders. The possibility of the application of neutron resonance spin echo (NRSE) for such a purpose is discussed, where the field borders are defined by current sheets. Prototype SERGIS experiments performed on holographically made optical gratings at a NRSE triple-axis spectrometer are shown. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Max Planck Inst Met Res, D-70569 Stuttgart, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Hahn Meitner Inst Berlin GmbH, BENSC, D-14109 Berlin, Germany. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. RP Major, J (reprint author), Max Planck Inst Met Res, Heisenbergstr 3, D-70569 Stuttgart, Germany. RI te Velthuis, Suzanne/I-6735-2013; Habicht, Klaus/K-3636-2013 OI te Velthuis, Suzanne/0000-0002-1023-8384; Habicht, Klaus/0000-0002-9915-7221 NR 30 TC 29 Z9 29 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD AUG PY 2003 VL 336 IS 1-2 BP 8 EP 15 DI 10.1016/S0921-4526(03)00264-3 PG 8 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600003 ER PT J AU Yacoby, Y Sowwan, M Stern, E Cross, J Brewe, D Pindak, R Pitney, J Dufresne, EB Clarke, R AF Yacoby, Y Sowwan, M Stern, E Cross, J Brewe, D Pindak, R Pitney, J Dufresne, EB Clarke, R TI Direct determination of epitaxial film and interface structure: Gd2O3 on GaAs (100) SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CALIFORNIA DE diffraction phase; X-ray diffraction; passivation layer ID SURFACE; PASSIVATION; OXIDE AB We present a new method of sub-Angstrom resolution imaging of the 3D structure of epitaxial films and their interface with the substrate. The method utilizes the diffraction intensities along the substrate-defined Bragg rods and some crude knowledge of the system structure to determine the complex scattering factors (CSFs) along the Bragg rods. The system electron density and the structure is obtained by Fourier transforming the CSFs into real space. We have applied this method to study the structure of a Gd2O3 film and its interface with the GaAs substrate. The results show that the Gd2O3 abandons the bulk stacking order and adopts that of GaAs. Moreover, the atoms in the first few layers move to in-plane positions that overlap those of the underlying Ga and As. This behavior may be at the heart of its ability to passivate GaAs. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. Univ Washington, Dept Phys, Seattle, WA 98195 USA. Argonne Natl Lab, Adv Photon Source, PNC, CAT, Argonne, IL 60439 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. Argonne Natl Lab, Adv Photon Source, MHATT, CAT, Argonne, IL 60439 USA. Univ Michigan, Dept Phys, FOCUS Ctr, Ann Arbor, MI 48109 USA. RP Yacoby, Y (reprint author), Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. OI Sowwan, Mukhles/0000-0002-0211-2124 NR 11 TC 8 Z9 8 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD AUG PY 2003 VL 336 IS 1-2 BP 39 EP 45 DI 10.1016/S0921-4526(03)00267-9 PG 7 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600006 ER PT J AU Ankner, JF Rehm, C AF Ankner, JF Rehm, C TI Time-dependent measurements at the SNS liquids reflectometer SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CALIFORNIA DE neutron reflectometry; hydrogen in metals; time-dependent measurements; neutron instrumentation ID NEUTRON REFLECTION AB The greatly increased flux that will be available at the Spallation Neutron Source (SNS) should enhance our ability to carry out time-resolved reflectivity measurements. Construction of horizontal- and vertical-surface reflectometers is well underway and the instruments will be commissioned in early 2006. We consider how to utilize the intrinsic wavelength bandwidth of the SNS to perform "snapshot" reflectivity measurements, using the outgassing of a hydrogen-charged Fe/Nb multilayer as a test case. At the expected SNS source flux of 2 MW, we determine that kinetics in our rather favorable test case can be observed with as short as a 1-s time resolution. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37831 USA. RP Ankner, JF (reprint author), Oak Ridge Natl Lab, Spallat Neutron Source, Oak Ridge, TN 37831 USA. OI Ankner, John/0000-0002-6737-5718 NR 8 TC 1 Z9 3 U1 1 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 AUG PY 2003 VL 336 IS 1-2 BP 68 EP 74 DI 10.1016/S0921-4526(03)00271-0 PG 7 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600010 ER PT J AU Stephenson, GB Fong, DD Murty, MVR Streiffer, SK Eastman, JA Auciello, O Fuoss, PH Munkholm, A Aanerud, MEM Thompson, C AF Stephenson, GB Fong, DD Murty, MVR Streiffer, SK Eastman, JA Auciello, O Fuoss, PH Munkholm, A Aanerud, MEM Thompson, C TI In situ X-ray studies of vapor phase epitaxy of PbTiO3 SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CALIFORNIA DE ferroelectrics; metal organic vapor phase epitaxy; in situ; grazing incidence X-ray scattering ID THIN-FILMS AB As part of a program to understand and control the structure of ferroelectric thin films grown by metal organic vapor phase epitaxy (MOVPE), we have used X-ray scattering to observe the surface structure of PbTiO3 films during and following growth. Moderately high energy (24 keV) X-rays are used to penetrate the chamber walls for in situ measurements in the high-temperature, reactive MOVPE environment. Performing measurements in situ allows us to study the growth process in real time, to control the thickness of the films to sub-unit-cell accuracy, to observe the surface structure in equilibrium with the vapor, and to preserve film stoichiometry during high-temperature study by maintaining an overpressure of PbO. While the higher X-ray energy also permits a large volume of reciprocal space to be mapped, it presents challenges for surface scattering due to the small critical angle. Examples of results will be presented from studies of surface structure dynamics, crystal growth, and ferroelectric stripe domains in thin films. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Lumileds Lighting, San Jose, CA 95131 USA. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. RP Stephenson, GB (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Streiffer, Stephen/A-1756-2009; Eastman, Jeffrey/E-4380-2011; OI Eastman, Jeff/0000-0002-0847-4265; Thompson, Carol/0000-0003-3832-4855 NR 10 TC 17 Z9 17 U1 0 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD AUG PY 2003 VL 336 IS 1-2 BP 81 EP 89 DI 10.1016/S0921-4526(03)00273-4 PG 9 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600012 ER PT J AU Hellwig, O Denbeaux, GP Kortright, JB Fullerton, EE AF Hellwig, O Denbeaux, GP Kortright, JB Fullerton, EE TI X-ray studies of aligned magnetic stripe domains in perpendicular multilayers SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CALIFORNIA DE magnetic domains; perpendicular magnetic anisotropy; X-ray scattering; magnetic microscopy; magnetic thin films ID DIFFRACTION; MICROSCOPY; FILMS AB We have investigated the stripe domain structure and the magnetic reversal of perpendicular Co/Pt-based multilayers at room temperature using magnetometry, magnetic imaging and magnetic X-ray scattering. In-plane field cycling aligns the stripe domains along the field direction. In magnetic X-ray scattering the parallel stripe domains act as a magnetic grating resulting in observed Bragg reflections up to fifth order. We model the scattering profile to extract and quantify the domain as well as domain wall widths. Applying fields up to similar to 1.2 kOe perpendicular to the film reversibly changes the relative width of up versus down domains while maintaining the overall stripe periodicity. Fields above 1.2 kOe introduce irreversible changes into the domain structure by contracting and finally annihilating individual stripe domains. We compare the current results with modeling and previous measurements of films with perpendicular anisotropy. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Hitachi Global Storage Technol, San Jose Res Ctr, San Jose, CA 95120 USA. RP Kortright, JB (reprint author), Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 17 TC 55 Z9 55 U1 2 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD AUG PY 2003 VL 336 IS 1-2 BP 136 EP 144 DI 10.1016/S0921-4526(03)00282-5 PG 9 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600020 ER PT J AU Yu, KL Lin, MZ Lee, CH Ku, CA Huang, JCA Velthuis, SGET AF Yu, KL Lin, MZ Lee, CH Ku, CA Huang, JCA Velthuis, SGET TI Polarized neutron and X-ray reflectivity study of the structure and exchange coupling of permalloy(Ni80Fe20)/Cr/permalloy trilayers SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CA DE polarized neutron reflectivity; interlayer anti ferromagnetic coupling; X-ray scattering; permalloy/Cr multilayers ID MULTILAYERS; SANDWICHES; MECHANISM AB The magnetic coupling between two permalloy layers with a Cr separating layer was studied using LMOKE, polarized neutron reflectivity and XRD. The coupling between two permalloy layers is anti ferromagnetic-like when the Cr thickness is near 2.0 nm along the easy axis. A strong biquadratic coupling term has been found from the polarized neutron reflectivity study. The strong biquadratic coupling may be caused by the rough interface between the permalloy and Cr layers. The missing GMR effect of this system might be due to this strong biquadratic coupling of permalloy layers. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Natl Tsing Hua Univ, Dept Engn & Syst Sci, Hsinchu 30043, Taiwan. Natl Tsing Hua Univ, Nucl Sci & Technol Res Ctr, Nucl Reactor Div, Hsinchu 30043, Taiwan. Natl Cheng Kung Univ, Dept Phys, Tainan 701, Taiwan. Argonne Natl Lab, Div Sci Mat, Argonne Natl Lab, Argonne, IL 60439 USA. RP Yu, KL (reprint author), Natl Tsing Hua Univ, Dept Engn & Syst Sci, Hsinchu 30043, Taiwan. EM chlee@mx.nthu.edu.tw RI te Velthuis, Suzanne/I-6735-2013; OI te Velthuis, Suzanne/0000-0002-1023-8384; Lee, Chih-Hao/0000-0002-3898-6421 NR 16 TC 3 Z9 3 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 AUG PY 2003 VL 336 IS 1-2 BP 151 EP 156 DI 10.1016/S0921-4526(03)00284-9 PG 6 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600022 ER PT J AU Han, SW Farmer, J Miceli, PF Felcher, G Goyette, R Kiehne, GT Ketterson, JB AF Han, SW Farmer, J Miceli, PF Felcher, G Goyette, R Kiehne, GT Ketterson, JB TI Distribution of vortices in Nb/Al multilayers studied by spin-polarized neutron reflectivity and magnetization SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CALIFORNIA DE SPNR; spin-polarized neutron reflectivity; Nb/Al multilayers; superconductivity ID FIELD PENETRATION DEPTH; SUPERCONDUCTING FILMS; THIN-FILMS; LAYERED SUPERCONDUCTORS; SURFACE-BARRIER; TYPE-2 SUPERCONDUCTORS; PHASE-TRANSITION; REFLECTOMETRY; YBA2CU3O7-X; PARALLEL AB We present SPNR and DC magnetization studies of non-uniformly distributed vortices in Nb/Al multilayers for fields applied near-parallel to the film surface. Peaks are observed in the M-H curves that are shown to correspond to vortex row-transitions and the field values of the transitions agree well with free energy calculations. An additional peak is observed at an applied field smaller than the first row-transition field and this is shown to arise from the lower critical field parallel to the surface. Demagnetization effects are discussed. SPNR measurements performed at low field give the London penetration length and measurements in the mixed state are consistent with a single row of vortices residing in the film center, but with positional fluctuations amounting to 1/4 of the film thickness. It is also shown that cycling the applied field leads to a surface-induced reorientation of the vortex magnetic field, which points perpendicular to the surface in zero field. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Univ Missouri, Res Reactor, Columbia, MO 65211 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. Northwestern Univ, Mat Res Ctr, Evanston, IL 60208 USA. RP Miceli, PF (reprint author), Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. RI Ketterson, John/B-7234-2009 NR 30 TC 2 Z9 2 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 AUG PY 2003 VL 336 IS 1-2 BP 162 EP 172 DI 10.1016/S0921-4526(03)00286-2 PG 11 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600024 ER PT J AU Mochrie, SGJ Lurio, LB Ruhm, A Lumma, D Borthwick, M Falus, P Kim, HJ Basu, JK Lal, J Sinha, SK AF Mochrie, SGJ Lurio, LB Ruhm, A Lumma, D Borthwick, M Falus, P Kim, HJ Basu, JK Lal, J Sinha, SK TI X-ray photon correlation spectroscopy studies of colloidal diffusion and the capillary modes of polymer films SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CALIFORNIA DE XPCS; photon correlation spectroscopy; coherence; dynamics ID INTERACTING BROWNIAN PARTICLES; GLASS-TRANSITION TEMPERATURE; POLYSTYRENE LATEX SPHERES; DYNAMIC LIGHT-SCATTERING; THIN-FILMS; MOTION; SUSPENSIONS; DISPERSIONS; INTERFACE; MONODISPERSE AB The new method of X-ray photon correlation spectroscopy (XPCS) is introduced with reference to experiments studying diffusion in concentrated colloidal suspensions. It is shown that both the static structure and the diffusional dynamics of concentrated suspensions of polystyrene spheres in glycerol are well-described by theories developed for hard spheres. Next, XPCS experiments probing the dynamics of surface height fluctuations as a function of lateral length scale are described. Measurements were performed on polystyrene (PS) thin films of thicknesses varying from 840 to 3330 Angstrom at temperatures above the PS glass transition temperature. Within a range of wave vectors spanning 10(-4)-10(-3) Angstrom(-1), good agreement is found between the measured surface dynamics and the theory of overdamped thermal capillary waves on thin films. Quantitatively, the data can be accounted for using the viscosity of bulk PS. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Yale Univ, Dept Phys & Appl Phys, New Haven, CT 06520 USA. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. Sogang Univ, Dept Phys, Seoul 121742, South Korea. Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Los Alamos Natl Lab, LANSCE, Los Alamos, NM 87545 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Mochrie, SGJ (reprint author), Yale Univ, Dept Phys & Appl Phys, New Haven, CT 06520 USA. NR 36 TC 11 Z9 11 U1 0 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD AUG PY 2003 VL 336 IS 1-2 BP 173 EP 180 DI 10.1016/S0921-4526(03)00287-4 PG 8 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600025 ER PT J AU Kim, H Ruhm, A Lurio, LB Basu, JK Lal, J Mochrie, SGJ Sinha, SK AF Kim, H Ruhm, A Lurio, LB Basu, JK Lal, J Mochrie, SGJ Sinha, SK TI X-ray photon correlation spectroscopy on polymer films with molecular weight dependence SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 7th International Conference on Surface X-Ray and Neutron Scattering (7SXNS) CY SEP, 2002 CL LAKE TAHOE, CALIFORNIA DE X-ray photon correlation spectroscopy; X-ray reflectivity; polymer films AB We have applied X-ray photon correlation spectroscopy (XPCS) to study the dynamics of surface fluctuations in thin supported polystyrene films as a function of wave vector, temperature, film thickness, and molecular weight. Molecular weights, ranging from 30 to 650 kg/mol, were used in the study. Lateral length scales probed are at least ten times smaller than those accessible in conventional dynamic light scattering. Good agreement between the experimental results and conventional theory permits us to determine the film viscosity. The viscosity obtained in thin films with a higher molecular weight shows lower viscosity than the one obtained from bulk polystyrene of corresponding molecular weight. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Sogang Univ, Dept Phys, Seoul 100611, South Korea. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Los Alamos Natl Lab, LANSCE, Los Alamos, NM 87545 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Max Planck Inst Met Res, Stuttgart, Germany. MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. Yale Univ, Dept Appl Phys, New Haven, CT 06520 USA. RP Kim, H (reprint author), Sogang Univ, Dept Phys, CPO Box 1142, Seoul 100611, South Korea. NR 11 TC 6 Z9 6 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD AUG PY 2003 VL 336 IS 1-2 BP 211 EP 215 DI 10.1016/S0921-4526(03)00291-6 PG 5 WC Physics, Condensed Matter SC Physics GA 699DL UT WOS:000184040600029 ER PT J AU Dunning, FB Reinhold, CO Burgdorfer, J AF Dunning, FB Reinhold, CO Burgdorfer, J TI The kicked Rydberg atom: A new laboratory for study of non-linear dynamics SO PHYSICA SCRIPTA LA English DT Editorial Material ID ELECTRON-ION RECOMBINATION; HYDROGEN-ATOMS; STABILIZATION; REALIZATION; FIELD AB Recent advances in experimental technique have enabled the study of atoms subject to impulsive perturbations of duration T(p) << T(n), where T(n) is the classical electron orbital period. Such "kicked" atoms provide new opportunities for the control and manipulation of atomic wavefunctions and for the investigation of non-linear dynamics in Hamiltonian systems. Here we discuss the rich variety of dynamical behaviors that are observed and their physical origins, together with several possible avenues for future research. C1 Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Vienna Univ Technol, Inst Theoret Phys, A-1040 Vienna, Austria. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Dunning, FB (reprint author), Rice Univ, Dept Phys & Astron, MS-61,6100 Main St, Houston, TX 77005 USA. OI Reinhold, Carlos/0000-0003-0100-4962 NR 13 TC 2 Z9 2 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0031-8949 J9 PHYS SCRIPTA JI Phys. Scr. PD AUG PY 2003 VL 68 IS 2 BP C44 EP C47 DI 10.1238/Physica.Regular.068aC0044 PG 4 WC Physics, Multidisciplinary SC Physics GA 712AZ UT WOS:000184774400013 ER PT J AU Butov, LV AF Butov, LV TI Condensation and pattern formation in cold exciton gases SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 7th International Workshop on Nonlinear Optics and Excitation Kinetics in Semiconductors (NOEKS 7) CY FEB 24-28, 2003 CL UNIV KARLSRUHE, KARLSRUHE, GERMANY HO UNIV KARLSRUHE ID COUPLED QUANTUM-WELLS; BOSE-EINSTEIN CONDENSATION; POTENTIAL TRAPS; NOBEL LECTURE; ELECTRON; CU2O; STATISTICS; DIMENSIONS; TRANSPORT; SYSTEMS AB Excitons are Bose particles with small mass. Exciton Bose-Einstein condensation is expected to occur at a few degrees Kelvin. Experimentally, an exciton temperature well below 1 Kelvin is achieved in coupled quantum wells (CQWs). In this contribution, we review briefly experiments that show a strong enhancement of the exciton scattering rate with increasing exciton concentration revealing bosonic stimulation of exciton scattering, which is a signature of a degenerate Bose-gas of excitons. Novel experiments with exciton condensation in potential traps, pattern formation in exciton system and macroscopically ordered exciton state are also reviewed briefly. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. C1 EO Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Russia. RP Butov, LV (reprint author), EO Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. NR 34 TC 2 Z9 2 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD AUG PY 2003 VL 238 IS 3 BP 381 EP 388 DI 10.1002/pssb.200303150 PG 8 WC Physics, Condensed Matter SC Physics GA 714QK UT WOS:000184924800003 ER PT J AU Kaindl, RA Hagele, D Carnahan, MA Lovenich, R Chemla, DS AF Kaindl, RA Hagele, D Carnahan, MA Lovenich, R Chemla, DS TI Exciton dynamics studied via internal THz transitions SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 7th International Workshop on Nonlinear Optics and Excitation Kinetics in Semiconductors (NOEKS 7) CY FEB 24-28, 2003 CL UNIV KARLSRUHE, KARLSRUHE, GERMANY HO UNIV KARLSRUHE ID QUANTUM-WELL; SEMICONDUCTORS AB We employ a novel, ultrafast terahertz probe to investigate the dynamical interplay of optically-induced excitons and unbound electron-hole pairs in GaAs quantum wells. Resonant creation of heavy-hole excitons induces a new low-energy oscillator linked to transitions between the internal exciton degrees of freedom. The time-resolved terahertz optical conductivity is found to be a probe well suited for studies of fundamental processes such as formation, relaxation and ionization of excitons. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EO Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Hannover, Inst Festkorperphys, D-30167 Hannover, Germany. RP Kaindl, RA (reprint author), Univ Calif Berkeley, Dept Phys, MS 2-344,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 14 TC 4 Z9 4 U1 1 U2 8 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD AUG PY 2003 VL 238 IS 3 BP 451 EP 454 DI 10.1002/pssb.200303161 PG 4 WC Physics, Condensed Matter SC Physics GA 714QK UT WOS:000184924800014 ER PT J AU Schneider, HC Chow, WW Koch, SW AF Schneider, HC Chow, WW Koch, SW TI Influence of coupling between localized and continuum states in InGaN quantum-dot systems SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 7th International Workshop on Nonlinear Optics and Excitation Kinetics in Semiconductors (NOEKS 7) CY FEB 24-28, 2003 CL UNIV KARLSRUHE, KARLSRUHE, GERMANY HO UNIV KARLSRUHE ID LASER GAIN; GAN; WELLS; ALN AB This paper investigates the influence of the coupling between localized and continuum states on the optical absorption in wide-bandgap nitride-based quantum-dot structures under high-excitation conditions. Calculating the optical susceptibility in the presence of strong many-body Coulomb interactions and the quantum-confined Stark effect, we show that the interplay of these effects results in absorption/ gain features that depend on the quantum-dot dimensions in a nontrivial way. C1 Univ Kaiserslautern, Dept Phys, D-67653 Kaiserslautern, Germany. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Marburg, Dept Phys, D-35037 Marburg, Germany. Univ Marburg, Ctr Mat Sci, D-35037 Marburg, Germany. RP Schneider, HC (reprint author), Univ Kaiserslautern, Dept Phys, POB 3049, D-67653 Kaiserslautern, Germany. RI Schneider, Hans Christian/B-9450-2009 OI Schneider, Hans Christian/0000-0001-7656-4919 NR 15 TC 6 Z9 6 U1 2 U2 3 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD AUG PY 2003 VL 238 IS 3 BP 589 EP 592 DI 10.1002/pssb.200303176 PG 4 WC Physics, Condensed Matter SC Physics GA 714QK UT WOS:000184924800040 ER PT J AU Chen, MH Cheng, KT Beiersdorfer, P Sapirstein, J AF Chen, MH Cheng, KT Beiersdorfer, P Sapirstein, J TI Transition energies of the 3s-3p(3/2) resonance lines in sodiumlike to phosphoruslike uranium SO PHYSICAL REVIEW A LA English DT Article ID CONFIGURATION-INTERACTION CALCULATIONS; BEAM ION-TRAP; PERTURBATION-THEORY CALCULATIONS; HELIUM-LIKE IONS; LAMB-SHIFT CALCULATIONS; MANY-BODY CALCULATIONS; HIGHLY-CHARGED IONS; X-RAY SPECTROMETER; CU-LIKE IONS; VACUUM-POLARIZATION AB Spectral lines from the 3s-3p(3/2) transitions in Na-like to P-like uranium have been measured at the Lawrence Livermore National Laboratory EBIT-I electron-beam ion trap facility. The measured x-ray energies are among the most accurate spectroscopic data available for highly charged heavy ions and provide important tests of relativistic atomic structure theory as well as bound-state quantum electrodynamic (QED) corrections in strong fields. Relativistic configuration-interaction (RCI) calculations based on the no-pair Hamiltonian with B-spline basis functions have been carried out to study these transitions. Our RCI energies, corrected by many-electron screened QED corrections also calculated here, yield theoretical results in very good agreement with experiment. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RP Chen, MH (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM chen7@llnl.gov; ktcheng@llnl.gov; beiersdorfer@llnl.gov; jsapirst@nd.edu NR 51 TC 15 Z9 15 U1 0 U2 3 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 AUG PY 2003 VL 68 IS 2 AR 022507 DI 10.1103/PhysRevA.68.022507 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 719FC UT WOS:000185192100051 ER PT J AU Kaganovich, ID Startsev, EA Davidson, RC AF Kaganovich, ID Startsev, EA Davidson, RC TI Comparison of quantum-mechanical and classical trajectory calculations of cross sections for ion-atom impact ionization of negative and positive ions for heavy-ion fusion applications SO PHYSICAL REVIEW A LA English DT Article ID ELECTRON PRODUCTION; PROTON COLLISIONS AB Stripping cross sections in nitrogen have been calculated using the classical trajectory approximation and the Born approximation of quantum mechanics for the outer shell electrons of 3.2 GeV I- and Cs+ ions. A large difference in cross section, up to a factor of 6, calculated in quantum mechanics and classical mechanics, has been obtained. Because at such high velocities the Born approximation is well validated, the classical trajectory approach fails to correctly predict the stripping cross sections at high energies for electron orbitals with low ionization potential. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kaganovich, ID (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 22 TC 9 Z9 9 U1 0 U2 1 PU AMERICAN 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 AUG PY 2003 VL 68 IS 2 AR 022707 DI 10.1103/PhysRevA.68.022707 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 719FC UT WOS:000185192100062 ER PT J AU Kalosakas, G Bishop, AR Kenkre, VM AF Kalosakas, G Bishop, AR Kenkre, VM TI Small-tunneling-amplitude boson-Hubbard dimer. II. Dynamics SO PHYSICAL REVIEW A LA English DT Article ID SELF-TRAPPING EQUATION; EINSTEIN CONDENSATE; QUANTUM DYNAMICS; STATES; REVIVALS; SOLITONS; COLLAPSE; VORTEX; MODEL AB We present analytical relations for the quantum evolution of the number difference of bosons between the two sites of a double-well potential, by using perturbative results for small tunneling amplitudes in the two-mode approximation. Results are obtained for two different initial conditions: completely localized states and coherent spin states. In the former case both the short and the long time behavior is investigated and the characteristic Bohr frequencies of the energy spectrum are determined. In the latter case we calculate the short time-scale evolution of the number difference. The analytical expressions compare favorably with direct numerical solutions of the quantum problem. Finally, we discuss the corresponding Gross-Pitaevskii (i.e., mean-field) dynamics and we point out the differences between the full quantum evolution and the mean-field evolution. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Univ New Mexico, Ctr Adv Studies, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. RP Kalosakas, G (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Kalosakas, George/L-6211-2013 OI Kalosakas, George/0000-0001-7763-718X NR 39 TC 32 Z9 32 U1 0 U2 2 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 AUG PY 2003 VL 68 IS 2 AR 023602 DI 10.1103/PhysRevA.68.023602 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 719FC UT WOS:000185192100088 ER PT J AU Poulin, D Laflamme, R Milburn, GJ Paz, JP AF Poulin, D Laflamme, R Milburn, GJ Paz, JP TI Testing integrability with a single bit of quantum information SO PHYSICAL REVIEW A LA English DT Article ID COMPUTATION AB We show that deterministic quantum computing with a single bit can determine whether the classical limit of a quantum system is chaotic or integrable using O(N) physical resources, where N is the dimension of the Hilbert space of the system under study. This is a square-root improvement over all known classical procedures. Our study relies strictly on the random matrix conjecture. We also present numerical results for the nonlinear kicked top. C1 Perimeter Inst Theoret Phys, Waterloo, ON N2J 2W9, Canada. Univ Waterloo, Inst Quantum Comp, Waterloo, ON N2L 3G1, Canada. Univ Queensland, Sch Phys Sci, Ctr Quantum Comp Technol, Brisbane, Qld 4072, Australia. Univ Buenos Aires, Fac Ciencias Exactas & Nat, Dept Fis JJ Giambiagi, RA-1428 Buenos Aires, DF, Argentina. Los Alamos Natl Lab, Div Theory, Los Alamos, NM 87545 USA. RP Poulin, D (reprint author), Perimeter Inst Theoret Phys, 35 King St N, Waterloo, ON N2J 2W9, Canada. RI MIlburn, Gerard/B-6381-2008; Poulin, David/A-1481-2010; Paz, Juan/C-5947-2008 OI MIlburn, Gerard/0000-0002-5404-9681; NR 16 TC 13 Z9 13 U1 0 U2 0 PU AMERICAN 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 AUG PY 2003 VL 68 IS 2 AR 022302 DI 10.1103/PhysRevA.68.022302 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 719FC UT WOS:000185192100020 ER PT J AU Rescigno, TN Baertschy, M McCurdy, CW AF Rescigno, TN Baertschy, M McCurdy, CW TI Resolution of phase ambiguities in electron-impact ionization amplitudes SO PHYSICAL REVIEW A LA English DT Article ID HYDROGEN AB The formal theory of atomic ionization by electron impact relates the breakup amplitude to an integral expression involving the exact wave function and an unperturbed final state that contains two Coulomb functions with effective, noninteger charges. This integral expression has an associated phase factor that diverges logarithmically on an infinite volume unless the effective charges are chosen to satisfy a kinematic relationship, the so-called "Peterkop condition." We derive the explicit form of the Peterkop phase for two commonly used models of electron-hydrogen ionization, the Temkin-Poet model and the collinear model. We show that the formal theory can be used to identify and remove this physically insignificant, volume-dependent phase from amplitudes computed using numerically stable integral expressions that do not satisfy the Peterkop condition. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Colorado, Dept Phys, Denver, CO 80217 USA. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94551 USA. RP Rescigno, TN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 13 TC 18 Z9 18 U1 0 U2 0 PU AMERICAN 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 AUG PY 2003 VL 68 IS 2 AR 020701 DI 10.1103/PhysRevA.68.020701 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 719FC UT WOS:000185192100003 ER PT J AU Scielzo, ND Freedman, SJ Fujikawa, BK Vetter, PA AF Scielzo, ND Freedman, SJ Fujikawa, BK Vetter, PA TI Recoil-ion charge-state distribution following the beta(+) decay of Na-21 SO PHYSICAL REVIEW A LA English DT Article ID NEUTRINO ANGULAR CORRELATION; K-SHELL IONIZATION; ABSOLUTE DETECTION EFFICIENCIES; OPTICAL OSCILLATOR-STRENGTHS; MICROCHANNEL PLATE DETECTOR; ELECTRONIC EXCITATION; INTERNAL IONIZATION; ENERGY SPECTRUM; HIGH-RESOLUTION; GROUND-STATE AB The charge-state distribution following the beta(+) decay of(21)Na has been measured, showing a larger than expected fraction of the daughter Ne-21 in positive charge states. No dependence on either the beta(+) or recoil nucleus energy is observed. The data are compared to a simple model based on the sudden approximation. Calculations suggest that a small but important contribution from recoil ionization has significant consequences for precision beta decay correlation experiments detecting recoil ions. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Scielzo, ND (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 64 TC 20 Z9 20 U1 1 U2 4 PU AMERICAN 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 AUG PY 2003 VL 68 IS 2 AR 022716 DI 10.1103/PhysRevA.68.022716 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 719FC UT WOS:000185192100071 ER PT J AU Smerzi, A Trombettoni, A AF Smerzi, A Trombettoni, A TI Nonlinear tight-binding approximation for Bose-Einstein condensates in a lattice SO PHYSICAL REVIEW A LA English DT Article ID OPTICAL LATTICES; TUNNEL ARRAYS; INSTABILITIES; TRANSITION; SUPERFLUID; INSULATOR; ATOMS; GAS AB The dynamics of Bose-Einstein condensates trapped in a deep optical lattice is governed by a discrete nonlinear equation (DNL). Its degree of nonlinearity and the intersite hopping rates are retrieved from a nonlinear tight-binding approximation taking into account the effective dimensionality of each condensate. We derive analytically the Bloch and the Bogoliubov excitation spectra and the velocity of sound waves emitted by a traveling condensate. Within a Lagrangian formalism, we obtain Newtonian-like equations of motion of localized wave packets. We calculate the ground-state atomic distribution in the presence of a harmonic confining potential, the frequencies of small amplitude dipole, and quadrupole oscillations. We finally quantize the DNL, recovering an extended Bose-Hubbard model. C1 Univ Trent, Ist Nazl Fis Mat, BEC, CRS, I-38050 Povo, Italy. Univ Trent, Dipartimento Fis, I-38050 Povo, Italy. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Parma, Ist Nazl Fis Mat, I-43100 Parma, Italy. Univ Parma, Dipartimento Fis, I-43100 Parma, Italy. RP Smerzi, A (reprint author), Univ Trent, Ist Nazl Fis Mat, BEC, CRS, I-38050 Povo, Italy. NR 35 TC 92 Z9 95 U1 2 U2 8 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 AUG PY 2003 VL 68 IS 2 AR 023613 DI 10.1103/PhysRevA.68.023613 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 719FC UT WOS:000185192100099 ER PT J AU Stolte, WC Sant'Anna, MM Ohrwall, G Dominguez-Lopez, I Piancastelli, MN Lindle, DW AF Stolte, WC Sant'Anna, MM Ohrwall, G Dominguez-Lopez, I Piancastelli, MN Lindle, DW TI Photofragmentation dynamics of core-excited water by anion-yield spectroscopy SO PHYSICAL REVIEW A LA English DT Article ID FAST DISSOCIATION; EXCITATION; FRAGMENTATION; OXYGEN; DECAY; CO2 AB Partial-anion and- cation yields from H2O are presented for photon energies near the oxygen K edge. The O- yield exhibits a feature above threshold attributed to doubly excited states, in contrast to the H- and cation yields, which are nearly featureless above threshold. Additionally, the lack of the OH- fragment indicates radiative decay and provides a negligible amount of anion formation. C1 Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Pontificia Univ Catolica Rio de Janeiro, Dept Fis, BR-22452970 Rio De Janeiro, Brazil. Uppsala Univ, Dept Phys, SE-75121 Uppsala, Sweden. Ctr Natl Metrol, Qreretaro 76900, Mexico. Univ Roma Tor Vergata, Dept Chem Sci & Technol, I-00133 Rome, Italy. RP Stolte, WC (reprint author), Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. RI Sant'Anna, Marcelo/B-9355-2013; Dominguez-Lopez, Ivan/B-6072-2016 OI Sant'Anna, Marcelo/0000-0001-5342-5799; Dominguez-Lopez, Ivan/0000-0001-8084-8711 NR 18 TC 27 Z9 27 U1 0 U2 7 PU AMERICAN 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 AUG PY 2003 VL 68 IS 2 AR 022701 DI 10.1103/PhysRevA.68.022701 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 719FC UT WOS:000185192100056 ER PT J AU Armitage, NP Lu, DH Kim, C Damascelli, A Shen, KM Ronning, F Feng, DL Bogdanov, P Zhou, XJ Yang, WL Hussain, Z Mang, PK Kaneko, N Greven, M Onose, Y Taguchi, Y Tokura, Y Shen, ZX AF Armitage, NP Lu, DH Kim, C Damascelli, A Shen, KM Ronning, F Feng, DL Bogdanov, P Zhou, XJ Yang, WL Hussain, Z Mang, PK Kaneko, N Greven, M Onose, Y Taguchi, Y Tokura, Y Shen, ZX TI Angle-resolved photoemission spectral function analysis of the electron-doped cuprate Nd1.85Ce0.15CuO4 SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; ENERGY; DISPERSION; STATE; BI2SR2CACU2O8+DELTA; SURFACE; GAP AB Using methods made possible by recent advances in photoemission technology, we perform an indepth line shape analysis of the angle-resolved photoemission spectra of the electron doped (n-type) cuprate superconductor Nd1.85Ce0.15CuO4. Unlike for the p-type materials, we only observe weak mass renormalizations near 50-70 meV. This may be indicative of smaller electron-phonon coupling or due to the masking effects of other interactions that make the electron-phonon coupling harder to detect. This latter scenario may suggest limitations of the spectral function analysis in extracting electronic self-energies when some of the interactions are highly momentum dependent. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Tokyo, Dept Appl Phys, Tokyo 1138656, Japan. RP Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. RI Shen, Kyle/B-3693-2008; Onose, Yoshinori/F-1977-2010; Taguchi, Yasujiro/A-3048-2010; Tokura, Yoshinori/C-7352-2009; damascelli, andrea/P-6329-2014; Yang, Wanli/D-7183-2011 OI damascelli, andrea/0000-0001-9895-2226; Yang, Wanli/0000-0003-0666-8063 NR 34 TC 46 Z9 46 U1 2 U2 12 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 AUG 1 PY 2003 VL 68 IS 6 AR 064517 DI 10.1103/PhysRevB.68.064517 PG 7 WC Physics, Condensed Matter SC Physics GA 720BH UT WOS:000185240600085 ER PT J AU Batista, CD Bonca, J Gubernatis, JE AF Batista, CD Bonca, J Gubernatis, JE TI Ferromagnetism in the strong hybridization regime of the periodic Anderson model SO PHYSICAL REVIEW B LA English DT Article ID KONDO-LATTICE MODEL; U HUBBARD-MODEL; GROUND-STATE; MAGNETISM; BEHAVIOR; SYSTEM; CE AB We determine exactly the ground state of the one-dimensional periodic Anderson model (PAM) in the strong hybridization regime. In this regime, the low energy sector of the PAM maps into an effective Hamiltonian that has a ferromagnetic ground state for any electron density between half and three-quarters filling. This rigorous result proves the existence of a new magnetic state that was excluded in the previous analysis of the mixed valence systems. C1 Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Ljubljana, FMF, Dept Phys, Ljubljana, Slovenia. Jozef Stefan Inst, Ljubljana, Slovenia. RP Batista, CD (reprint author), Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RI Batista, Cristian/J-8008-2016 NR 24 TC 9 Z9 9 U1 0 U2 2 PU AMERICAN 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 AUG 1 PY 2003 VL 68 IS 6 AR 064403 DI 10.1103/PhysRevB.68.064403 PG 4 WC Physics, Condensed Matter SC Physics GA 720BH UT WOS:000185240600046 ER PT J AU Brown, G Kraczek, B Janotti, A Schulthess, TC Stocks, GM Johnson, DD AF Brown, G Kraczek, B Janotti, A Schulthess, TC Stocks, GM Johnson, DD TI Competition between ferromagnetism and antiferromagnetism in FePt SO PHYSICAL REVIEW B LA English DT Article ID GENERALIZED-GRADIENT-APPROXIMATION; RANDOM SUBSTITUTIONAL ALLOYS; DENSITY-FUNCTIONAL THEORY; MAGNETIC-PROPERTIES; THIN-FILMS; STRUCTURAL-PROPERTIES; ELECTRONIC-STRUCTURE; TOTAL-ENERGY; COPT; NANOPARTICLES AB FePt in the L1(0) (tetragonal) phase is of interest due to its ease of synthesis as nanoparticles and because superparamagnetism is suppressed by the large magnetoanisotropy energy (MAE) of the L1(0) phase. Here we present the results of first-principles electronic-structure calculations that reveal a competition between ferromagnetic (FM) and antiferromagnetic (AFM) ordering of the alternating Fe planes, with energy differences less than room-temperature thermal energy. We find that the FM state is stabilized relative to the AFM state as L1(0) tetragonal distortion decreases or chemical (antisite) disorder increases on Pt planes. Inherently, then, there is a competition between stabilizing the FM state and maintaining the large MAE in FePt, and optimally maximizing both is important for nanomagnetic applications. C1 Oak Ridge Natl Lab, Ctr Computat Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Florida State Univ, Sch Computat Sci & Informat Technol, Tallahassee, FL 32306 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Ctr Computat Sci, Oak Ridge, TN 37831 USA. RI Janotti, Anderson/F-1773-2011; Brown, Gregory/F-7274-2016; Stocks, George Malcollm/Q-1251-2016 OI Janotti, Anderson/0000-0001-5028-8338; Brown, Gregory/0000-0002-7524-8962; Stocks, George Malcollm/0000-0002-9013-260X NR 36 TC 66 Z9 66 U1 0 U2 18 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD AUG 1 PY 2003 VL 68 IS 5 AR 052405 DI 10.1103/PhysRevB.68.052405 PG 4 WC Physics, Condensed Matter SC Physics GA 720BD UT WOS:000185240100011 ER PT J AU Chang, CH Wei, SH Johnson, JW Zhang, SB Leyarovska, N Bunker, G Anderson, TJ AF Chang, CH Wei, SH Johnson, JW Zhang, SB Leyarovska, N Bunker, G Anderson, TJ TI Local structure of CuIn3Se5: X-ray absorption fine structure study and first-principles calculations SO PHYSICAL REVIEW B LA English DT Article ID CRYSTAL-STRUCTURES; CUINSE2; SEMICONDUCTORS; DIFFRACTION; PHASES AB A detailed extended x-ray absorption fine structure (EXAFS) study of CuInSe2 and CuIn3Se5 on Cu-K, In-K, and Se-K edges was performed. It was found that CuInSe2 and CuIn3Se5 have well-defined local structure with the same average Cu-Se and In-Se bond lengths. They can be best described by structures containing weighted local tetrahedral cationic clusters around each Se: 2Cu+2In (k=8), and equal number of V-Cu+Cu+2In (k=7) and V-Cu+3In (k=9), where k denotes the nominal number of valence electrons of the cation clusters. CuInSe2 consists of 100% k=8 clusters and CuIn3Se5 consists of 20% k=8 and 40% k=7 and 40% k=9 clusters. First-principles band structure calculations of various CuInSe2, CuIn3Se5 and CuIn5Se8 compounds confirmed that the average Cu-Se and In-Se bond lengths in various ordered vacancy structures are identical to within the calculation uncertainty, in agreement with the present EXAFS measurements. The first-principles calculations also find that the formation energy of several possible crystal structures for CuIn3Se5 and CuIn5Se8 are very similar, which explains why the long-range order of CuIn3Se5 is not uniquely determined. C1 Oregon State Univ, Dept Chem Engn, Corvallis, OR 97331 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. IIT, Dept Phys, Chicago, IL 60616 USA. RP Chang, CH (reprint author), Oregon State Univ, Dept Chem Engn, Corvallis, OR 97331 USA. EM changch@che.orst.edu RI Krausnick, Jennifer/D-6291-2013; ID, MRCAT/G-7586-2011; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 25 TC 13 Z9 13 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD AUG 1 PY 2003 VL 68 IS 5 AR 054108 DI 10.1103/PhysRevB.68.054108 PG 9 WC Physics, Condensed Matter SC Physics GA 720BD UT WOS:000185240100034 ER PT J AU Chen, XJ Zhang, CL Gardner, JS Sarrao, JL Almasan, CC AF Chen, XJ Zhang, CL Gardner, JS Sarrao, JL Almasan, CC TI Variable-range-hopping conductivity of the half-doped bilayer manganite LaSr2Mn2O7 SO PHYSICAL REVIEW B LA English DT Article ID MIXED-VALENCE MANGANITES; NEGATIVE MAGNETORESISTANCE; COLOSSAL MAGNETORESISTANCE; DISORDERED SYSTEMS; SINGLE-CRYSTALS; CHARGE; LOCALIZATION; Y1-XPRXBA2CU3O7-DELTA; R(1-X)A(X)MNO(3); SEMICONDUCTORS AB We report measurements of the in-plane (rho(ab)) and out-of-plane (rho(c)) resistivities on a single crystal of the half-doped bilayer manganite LaSr2Mn2O7. In the temperature T range 220 to 300 K, the resistive anisotropy rho(c)/rho(ab)=A+B/T (A and B constants), which provides evidence for the variable-range-hopping conduction in the presence of a Coulomb gap. This hopping mechanism also accounts for the quadratic magnetic field H and sin(2)Phi dependences of the negative magnetoresistivity ln[rho(i)(T,H,Phi)/rho(i)(T,H=0)] (i=ab,c), where Phi is the in-plane angle between the magnetic field and the current. C1 Kent State Univ, Dept Phys, Kent, OH 44242 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chen, XJ (reprint author), Kent State Univ, Dept Phys, Kent, OH 44242 USA. RI Gardner, Jason/A-1532-2013 NR 28 TC 18 Z9 18 U1 1 U2 4 PU AMERICAN 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 AUG 1 PY 2003 VL 68 IS 6 AR 064405 DI 10.1103/PhysRevB.68.064405 PG 5 WC Physics, Condensed Matter SC Physics GA 720BH UT WOS:000185240600048 ER PT J AU Choi, J Sanderson, LAW Musfeldt, JL Ellern, A Kogerler, P AF Choi, J Sanderson, LAW Musfeldt, JL Ellern, A Kogerler, P TI Optical properties of the molecule-based magnet K-6[V15As6O42(H2O)]center dot 8H(2)O SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; V-15; CLUSTER; NANOTUBES; RESONANCE; NANORODS; MODEL; ION AB We report the reflectance and optical conductivity of solid K-6[V15As6O42(H2O)].8H(2)O over a wide energy range in order to investigate the charge degrees of freedom in this molecule-based magnet. The band centered at similar to1.2 eV is assigned as a V d-->d transition, whereas features at similar to3.7, 4.3, and 5.6 eV are attributed to O p-->Vd charge transfer excitations. The optical gap is similar to0.5 eV. We compare our results to recent electronic structure calculations and to the optical response of other traditional and nanoscopic vanadates. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Choi, J (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RI Kogerler, Paul/H-5866-2013 OI Kogerler, Paul/0000-0001-7831-3953 NR 38 TC 19 Z9 19 U1 0 U2 1 PU AMERICAN 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 AUG 1 PY 2003 VL 68 IS 6 AR 064412 DI 10.1103/PhysRevB.68.064412 PG 5 WC Physics, Condensed Matter SC Physics GA 720BH UT WOS:000185240600055 ER PT J AU Conti, E DeVoe, R Gratta, G Koffas, T Waldman, S Wodin, J Akimov, D Bower, G Breidenbach, M Conley, R Danilov, M Djurcic, Z Dolgolenko, A Hall, C Odian, A Piepke, A Prescott, CY Rowson, PC Skarpaas, K Vuilleumier, JL Wamba, K Zeldovich, O AF Conti, E DeVoe, R Gratta, G Koffas, T Waldman, S Wodin, J Akimov, D Bower, G Breidenbach, M Conley, R Danilov, M Djurcic, Z Dolgolenko, A Hall, C Odian, A Piepke, A Prescott, CY Rowson, PC Skarpaas, K Vuilleumier, JL Wamba, K Zeldovich, O TI Correlated fluctuations between luminescence and ionization in liquid xenon SO PHYSICAL REVIEW B LA English DT Article ID ARGON; SCINTILLATION; IONS AB The ionization of liquefied noble gases by radiation is known to be accompanied by fluctuations much larger than predicted by Poisson statistics. We have studied the fluctuations of both scintillation and ionization in liquid xenon and have measured a strong anti-correlation between the two at a microscopic level, with coefficient -0.80pi(-)p process in He-4 SO PHYSICAL REVIEW C LA English DT Article ID COLOR-TRANSPARENCY; MOMENTUM-TRANSFER; SCATTERING; PHOTOPRODUCTION; DEPENDENCE; PIONS; Q(2); QCD AB We have measured the nuclear transparency of the fundamental process gamman-->pi(-)p in He-4. These measurements were performed at Jefferson Lab in the photon energy range of 1.6-4.5 GeV and at theta(cm)(pi)=70degrees and 90degrees. These measurements are the first of their kind in the study of nuclear transparency in photoreactions. They also provide a benchmark test of Glauber calculations based on traditional models of nuclear physics. The transparency results suggest deviations from the traditional nuclear physics picture. The momentum transfer dependence of the measured nuclear transparency is consistent with Glauber calculations that include the quantum chromodynamics phenomenon of color transparency. C1 Duke Univ, Durham, NC 27708 USA. MIT, Cambridge, MA 02139 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Coll William & Mary, Williamsburg, VA 23185 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Univ Maryland, College Pk, MD 20742 USA. Univ New Hampshire, Durham, NH 03824 USA. Univ Illinois, Urbana, IL 61801 USA. Florida Int Univ, Miami, FL 33199 USA. Rutgers State Univ, New Brunswick, NJ 08903 USA. Lund Univ, S-22100 Lund, Sweden. Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. Univ Colorado, Boulder, CO 80302 USA. Temple Univ, Philadelphia, PA 19122 USA. N Carolina Cent Univ, Durham, NC 27707 USA. Old Dominion Univ, Norfolk, VA 23529 USA. Univ Georgia, Athens, GA 30601 USA. RP Dutta, D (reprint author), Duke Univ, Durham, NC 27708 USA. RI Averett, Todd/A-2969-2011; Gao, Haiyan/G-2589-2011; Arrington, John/D-1116-2012; Holt, Roy/E-5803-2011; Reimer, Paul/E-2223-2013 OI Arrington, John/0000-0002-0702-1328; NR 30 TC 19 Z9 19 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD AUG PY 2003 VL 68 IS 2 AR 021001 DI 10.1103/PhysRevC.68.021001 PG 5 WC Physics, Nuclear SC Physics GA 719FM UT WOS:000185193000001 ER PT J AU Friar, JL van Kolck, U Payne, GL Coon, SA AF Friar, JL van Kolck, U Payne, GL Coon, SA TI Charge-symmetry breaking and the two-pion-exchange two-nucleon interaction SO PHYSICAL REVIEW C LA English DT Article ID EFFECTIVE-FIELD THEORY; CHIRAL LAGRANGIANS; NUCLEAR-FORCES; SCATTERING LENGTHS; 2-PION EXCHANGE; ASYMMETRY; INDEPENDENCE; VIOLATION; QUARKS AB Charge-symmetry breaking in the nucleon-nucleon force is investigated within an effective field theory, using a classification of isospin-violating interactions based on power-counting arguments. The relevant charge-symmetry-breaking interactions corresponding to the first two orders in the power counting are discussed, including their effects on the He-3-H-3 binding-energy difference. The static charge-symmetry-breaking potential linear in the nucleon-mass difference is constructed using chiral perturbation theory. Explicit formulas in momentum and configuration spaces are presented. The present work completes previously obtained results. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. US DOE, Div Nucl Phys, Washington, DC 20585 USA. RP Friar, JL (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 58 TC 35 Z9 35 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD AUG PY 2003 VL 68 IS 2 AR 024003 DI 10.1103/PhysRevC.68.024003 PG 7 WC Physics, Nuclear SC Physics GA 719FM UT WOS:000185193000010 ER PT J AU Garrett, PE Younes, W Becker, JA Bernstein, LA Baum, EM DiPrete, DP Gatenby, RA Johnson, EL McGrath, CA Yates, SW Devlin, M Fotiades, N Nelson, RO Brown, BA AF Garrett, PE Younes, W Becker, JA Bernstein, LA Baum, EM DiPrete, DP Gatenby, RA Johnson, EL McGrath, CA Yates, SW Devlin, M Fotiades, N Nelson, RO Brown, BA TI Nuclear structure of the closed subshell nucleus Zr-90 studied with the (n,n 'gamma) reaction SO PHYSICAL REVIEW C LA English DT Article ID DOPPLER-SHIFT ATTENUATION; SHELL-MODEL CALCULATIONS; 3(1)(-) STATES; SCATTERING; 90ZR; TRANSITIONS; EXCITATIONS; CHARACTER; ISOTONES; DECAY AB States in Zr-90 have been observed with the (n,n(')gamma) reaction using both spallation and monoenergetic accelerator-produced neutrons. A scheme comprised of 81 levels and 157 transitions was constructed concentrating on levels below 5.6 MeV in excitation energy. Spins have been determined by considering data from all experimental studies performed for Zr-90. Lifetimes have been deduced using the Doppler-shift attenuation method for many of the states, and transition rates have been obtained. A spherical shell-model interpretation in terms of particle-hole excitations assuming a Sr-88 closed core is given. In some cases, enhancements in B(M1) and B(E2) values are observed that cannot be explained by assuming simple particle-hole excitations. Shell-model calculations using an extended fpg-shell-model space reproduce the spectrum of excited states very well, and the gross features of the B(M1) and B(E2) transition rates. Transition rates for individual levels show discrepancies between calculations and experimental values. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Kentucky, Lexington, KY 40506 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. RP Garrett, PE (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI McGrath, Christopher/E-8995-2013; Devlin, Matthew/B-5089-2013 OI Devlin, Matthew/0000-0002-6948-2154 NR 42 TC 17 Z9 17 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD AUG PY 2003 VL 68 IS 2 AR 024312 DI 10.1103/PhysRevC.68.024312 PG 21 WC Physics, Nuclear SC Physics GA 719FM UT WOS:000185193000025 ER PT J AU Higa, R Robilotta, MR AF Higa, R Robilotta, MR TI Two-pion exchange nucleon-nucleon potential: O(q(4)) relativistic chiral expansion SO PHYSICAL REVIEW C LA English DT Article ID PERTURBATION-THEORY; SCATTERING LENGTHS; MESON-EXCHANGE; NN-SCATTERING; LAGRANGIANS; SYMMETRY; FORCES; MODEL; EQUATIONS; DIAGRAMS AB We present a relativistic procedure for the chiral expansion of the two-pion exchange component of the NN potential, which emphasizes the role of intermediate piN subamplitudes. The relationship between power counting in piN and NN processes is discussed and results are expressed directly in terms of observable subthreshold coefficients. Interactions are determined by one- and two-loop diagrams, involving pions, nucleons, and other degrees of freedom, frozen into empirical subthreshold coefficients. The full evaluation of these diagrams produces amplitudes containing many different loop integrals. Their simplification by means of relations among these integrals leads to a set of intermediate results. Subsequent truncation to O(q(4)) yields the relativistic potential, which depends on six loop integrals, representing bubble, triangle, crossed box, and box diagrams. The bubble and triangle integrals are the same as in piN scattering and we have shown that they also determine the chiral structures of box and crossed box integrals. Relativistic threshold effects make our results to be not equivalent with those of the heavy baryon approach. Performing a formal expansion of our results in inverse powers of the nucleon mass, even in regions where this expansion is not valid, we recover most of the standard heavy baryon results. The main differences are due to the Goldberger-Treiman discrepancy and terms of O(q(3)), possibly associated with the iteration of the one-pion exchange potential. C1 Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo, Brazil. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Higa, R (reprint author), Univ Sao Paulo, Inst Fis, Caixa Postal 66318, BR-05315970 Sao Paulo, Brazil. NR 60 TC 38 Z9 38 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD AUG PY 2003 VL 68 IS 2 AR 024004 DI 10.1103/PhysRevC.68.024004 PG 30 WC Physics, Nuclear SC Physics GA 719FM UT WOS:000185193000011 ER PT J AU Hofmann, HM Hale, GM AF Hofmann, HM Hale, GM TI Microscopic calculation of the spin-dependent neutron scattering lengths on He-3 SO PHYSICAL REVIEW C LA English DT Article ID CROSS-SECTIONS; NUCLEI AB We report on the spin-dependent neutron scattering length on He-3 from a microscopic calculation of p-H-3, n-He-3, and d-H-2 scattering employing the Argonne v(18) nucleon-nucleon potential with and without additional three-nucleon force. The results of a comprehensive R-matrix analysis are compared to that of a recent measurement. The overall agreement for the scattering lengths is quite good. The imaginary parts of the scattering lengths are very sensitive to the inclusion of three-nucleon forces, whereas the real parts are almost insensitive. C1 Univ Erlangen Nurnberg, Inst Theoret Phys 3, D-91058 Erlangen, Germany. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Hofmann, HM (reprint author), Univ Erlangen Nurnberg, Inst Theoret Phys 3, Staudtstr 7, D-91058 Erlangen, Germany. NR 29 TC 19 Z9 19 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD AUG PY 2003 VL 68 IS 2 AR 021002 DI 10.1103/PhysRevC.68.021002 PG 4 WC Physics, Nuclear SC Physics GA 719FM UT WOS:000185193000002 ER PT J AU Paris, MW AF Paris, MW TI Electromagnetic response of confined Dirac particles SO PHYSICAL REVIEW C LA English DT Article ID DEEP-INELASTIC SCATTERING; DUALITY; PROTON AB The eigenstates of a single massless Dirac particle confined in a linear potential are calculated exactly by direct solution of the Dirac equation. The electromagnetic structure functions are calculated from the Dirac wave functions of the ground and excited states of the particle by coupling to its conserved vector current. We obtain the longitudinal and transverse structure functions as a function of (y) over tilde=nu-\q\, where nu and \q\ are the energy and momentum transferred to the target in its rest frame. At values of \q\greater than or similar to2.5 GeV, much larger than the characteristic energy scale similar to440 MeV of the confining potential, the response exhibits y scaling, a generalization of Bjorken scaling. We compare the exact structure functions with those obtained from the ground state wave functions in the plane wave impulse approximation. The deviation from the Callan-Gross relation is compared with the parton model prediction. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Basel, Dept Phys & Astron, Basel, Switzerland. RP Los Alamos Natl Lab, Div Theoret, MS B283, Los Alamos, NM 87545 USA. EM paris@lanl.gov NR 15 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 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD AUG PY 2003 VL 68 IS 2 AR 025201 DI 10.1103/PhysRevC.68.025201 PG 9 WC Physics, Nuclear SC Physics GA 719FM UT WOS:000185193000045 ER PT J AU Appelquist, T Dobrescu, BA Hopper, AR AF Appelquist, T Dobrescu, BA Hopper, AR TI Nonexotic neutral gauge bosons SO PHYSICAL REVIEW D LA English DT Article ID FERMION-PAIR PRODUCTION; COLLISIONS; SEARCH; PHYSICS; MODELS; LEP; ENERGY AB We study theoretical and experimental constraints on electroweak theories including a new color-singlet and electrically neutral gauge boson. We first note that the electric charges of the observed fermions imply that any such Z' boson may be described by a gauge theory in which the Abelian gauge groups are the usual hypercharge along with another U(1) component in a kinetic-diagonal basis. Assuming that the observed quarks and leptons have generation-independent U(1) charges, and that no new fermions couple to the standard model gauge bosons, we find that their U(1) charges form a two-parameter family consistent with anomaly cancellation and viable fermion masses, provided there are at least three right-handed neutrinos. We then derive bounds on the Z' mass and couplings imposed by direct production and Z-pole measurements. For generic charge assignments and a gauge coupling of electromagnetic strength, the strongest lower bound on the Z' mass comes from Z-pole measurements, and is of the order of 1 TeV. If the new U(1) charges are proportional to B-L, however, there is no tree-level mixing between the Z and Z', and the best bounds come from the absence of direct production at CERN LEP II and the Fermilab Tevatron. If the U(1) gauge coupling is one or two orders of magnitude below the electromagnetic one, these bounds are satisfied for most values of the Z' mass. C1 Yale Univ, Dept Phys, New Haven, CT 06520 USA. Fermilab Natl Accelerator Lab, Dept Theoret Phys, Batavia, IL 60510 USA. RP Appelquist, T (reprint author), Yale Univ, Dept Phys, New Haven, CT 06520 USA. NR 27 TC 93 Z9 93 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 035012 DI 10.1103/PhysRevD.68.035012 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600068 ER PT J AU Atwood, D Soni, A AF Atwood, D Soni, A TI Role of a charm factory in extracting CKM-phase information via B -> DK SO PHYSICAL REVIEW D LA English DT Article ID CP-VIOLATION AB In this paper we study the impact of data that can be obtained from a charm factory on the determination of the Cabibbo-Kobayashi-Maskawa parameter gamma from decays of the form B-->(DK)-K-0 where the D-0 decays to specific inclusive and exclusive final states. In particular, for each exclusive final state f, the charm factory can determine the strong phase difference between D-0-->f and (D) over bar (0)-->f by exploiting correlations in psi(3770)-->D-0(D) over bar (0). This provides crucial input to the determination of gamma via the interference of B+/--->(K+/-D0)-->f with B+/--->K+/-(D) over bar (0)-->f. We discuss how the method may be generalized to inclusive final states and illustrate with a toy model how such methods may offer one of the best means to determine gamma with O(10(8)-10(9)) B mesons. C1 Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Brookhaven Natl Lab, Theory Grp, Upton, NY 11973 USA. RP Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. NR 23 TC 49 Z9 49 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 033003 DI 10.1103/PhysRevD.68.033003 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600007 ER PT J AU Atwood, D Soni, A AF Atwood, D Soni, A TI Getting beta-alpha without penguin contributions SO PHYSICAL REVIEW D LA English DT Article ID CP ASYMMETRY; B-DECAYS; VIOLATION AB Oscillation effects in B-0-->KSD0 and related processes are considered to determine deltaequivalent tobeta-alpha+pi=2beta+gamma. We suggest that D-0 decays to CP eigenstates used in concert with inclusive D-0 decays provide a powerful method for determining delta cleanly. The CP asymmetry is expected to be less than or similar to40% for D-0 decays to non-CP eigenstates and less than or similar to80% for decays to CP eigenstates. This method can lead to a fairly accurate determination of delta with O(10(8)-10(9)) B mesons. C1 Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Brookhaven Natl Lab, Theory Grp, Upton, NY 11973 USA. RP Atwood, D (reprint author), Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. NR 24 TC 11 Z9 11 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 033009 DI 10.1103/PhysRevD.68.033009 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600013 ER PT J AU Babu, KS Pati, JC AF Babu, KS Pati, JC TI Radiative processes [tau ->mu gamma, mu -> e gamma and (g-2)(mu)] as probes of the extended supersymmetric standard model in SO(10) SO PHYSICAL REVIEW D LA English DT Article ID ANOMALOUS MAGNETIC-MOMENT; COUPLING-CONSTANT UNIFICATION; ELECTRIC-DIPOLE MOMENT; VECTOR-LIKE FAMILIES; PROTON DECAY; MUON G-2; FERMION MASSES; GAUGE-MODELS; LIGHT; SUPERGRAVITY AB The extended supersymmetric standard model (ESSM), motivated on several grounds, introduces two vectorlike families (16+(16) over bar) of SO(10) with masses of the order of one TeV. It is noted that the successful predictions of prior work on fermion masses and mixings, based on the MSSM embedded in SO(10), can be retained rather simply within the ESSM extension. These include an understanding of the smallness of V(cb)approximate to0.04 and the largeness of the nu(mu)-nu(tau) oscillation angle, sin(2)2theta(nu mu nu tau)(osc)approximate to1. We analyze the new contributions arising through the exchange of the vectorlike families of the ESSM to radiative processes including tau-->mugamma, mu-->egamma, b-->sgamma, the EDM of the muon and the muon (g-2). We show that the ESSM makes significant contributions especially to the decays tau-->mugamma and mu-->egamma and simultaneously to muon (g-2). For a large and plausible range of relevant parameters, we obtain a(mu)(ESSM)approximate to+(10-40)x10(-10), with a correlated prediction that tau-->mugamma should be discovered with an improvement in its current limit by a factor of 3-20. The implications for mu-->egamma are very similar. The muon EDM is within reach of the next generation experiments. Thus, the ESSM, with heavy leptons being lighter than about 1 TeV (say), can be probed effectively by radiative processes before a direct search for these vectorlike leptons and quarks is feasible at the CERN LHC. C1 Oklahoma State Univ, Dept Phys, Stillwater, OK 74078 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Babu, KS (reprint author), Oklahoma State Univ, Dept Phys, Stillwater, OK 74078 USA. NR 49 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 035004 DI 10.1103/PhysRevD.68.035004 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600060 ER PT J AU Cahn, RN Jackson, JD AF Cahn, RN Jackson, JD TI Spin-orbit and tensor forces in heavy-quark light-quark mesons: Implications of the new D-s state at 2.32 GeV SO PHYSICAL REVIEW D LA English DT Article AB We consider the spectroscopy of heavy-quark light-quark mesons with a simple model based on the nonrelativistic reduction of vector and scalar exchange between fermions. Four forces are induced: the spin-orbit forces on the light and heavy quark spins, the tensor force, and a spin-spin force. If the vector force is Coulombic, the spin-spin force is a contact interaction, and the tensor force and spin-orbit force on the heavy quark to order 1/m(1)m(2) are directly proportional. As a result, just two independent parameters characterize these perturbations. The measurement of the masses of three p-wave states suffices to predict the mass of the fourth. This technique is applied to the D-s system, where the newly discovered state at 2.32 GeV provides the third measured level, and to the D system. The mixing of the two J(P)=1(+) p-wave states is reflected in their widths and provides additional constraints. The resulting picture is at odds with previous expectations and raises new puzzles. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Cahn, RN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 13 TC 81 Z9 81 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 037502 DI 10.1103/PhysRevD.68.037502 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600083 ER PT J AU Carena, M Delgado, A Ponton, E Tait, TMP Wagner, CEM AF Carena, M Delgado, A Ponton, E Tait, TMP Wagner, CEM TI Precision electroweak data and unification of couplings in warped extra dimensions SO PHYSICAL REVIEW D LA English DT Article ID GRAND UNIFICATION; SUPERSYMMETRY; HIERARCHY; FIELDS; MODEL; MASS; RS1 AB Warped extra dimensions allow a novel way of solving the hierarchy problem, with all fundamental mass parameters of the theory naturally of the order of the Planck scale. The observable value of the Higgs vacuum expectation value is redshifted, due to the localization of the Higgs field in the extra dimension. It has been recently observed that, when the gauge fields propagate in the bulk, unification of the gauge couplings may be achieved. Moreover, the propagation of fermions in the bulk allows for a simple solution to potentially dangerous proton decay problems. However, bulk gauge fields and fermions pose a phenomenological challenge, since they tend to induce large corrections to the precision electroweak observables. In this article, we study in detail the effect of gauge and fermion fields propagating in the bulk in the presence of gauge brane kinetic terms compatible with gauge coupling unification, and we present ways of obtaining a consistent description of experimental data, while allowing values of the first Kaluza-Klein mode masses of the order of a few TeV. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Argonne Natl Lab, HEP Div, Argonne, IL 60439 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. RI Ponton, Eduardo/I-4125-2013 OI Ponton, Eduardo/0000-0003-3138-1136 NR 52 TC 87 Z9 87 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 035010 DI 10.1103/PhysRevD.68.035010 PG 16 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600066 ER PT J AU Csaki, C Hubisz, J Kribs, GD Meade, P Terning, J AF Csaki, C Hubisz, J Kribs, GD Meade, P Terning, J TI Variations of little Higgs models and their electroweak constraints SO PHYSICAL REVIEW D LA English DT Article ID PARTICLES AB We calculate the tree-level electroweak precision constraints on a wide class of little Higgs models including variations of the littlest Higgs SU(5)/SO(5), SU(6)/Sp(6), and SU(4)(4)/SU(3)(4) models. By performing a global fit to the precision data we find that for generic regions of the parameter space the bound on the symmetry breaking scale f is several TeV, where we have kept the normalization of f constant in the different models. For example, the "minimal" implementation of SU(6)/Sp(6) is bounded by f>3.0 TeV throughout most of the parameter space, and SU(4)(4)/SU(3)(4) is bounded by f(2)equivalent tof(1)(2)+f(2)(2)>(4.2 TeV)(2). In certain models, such as SU(4)(4)/SU(3)(4), a large f does not directly imply a large amount of fine-tuning since the heavy-fermion masses that contribute to the Higgs boson mass can be lowered below f for a carefully chosen set of parameters. We also find that for certain models (or variations) there exist regions of parameter space in which the bound on f can be lowered into the range 1-2 TeV. These regions are typically characterized by a small mixing between heavy and standard model gauge bosons and a small (or vanishing) coupling between heavy U(1) gauge bosons and light fermions. Whether such a region of parameter space is natural or not is ultimately contingent on the UV completion. C1 Cornell Univ, Newman Lab Elementary Particle Phys, Ithaca, NY 14853 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Los Alamos Natl Lab, Theory Div T8, Los Alamos, NM 87545 USA. RP Csaki, C (reprint author), Cornell Univ, Newman Lab Elementary Particle Phys, Ithaca, NY 14853 USA. NR 34 TC 226 Z9 226 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 035009 DI 10.1103/PhysRevD.68.035009 PG 18 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600065 ER PT J AU Dawson, S Jackson, C Orr, LH Reina, L Wackeroth, D AF Dawson, S Jackson, C Orr, LH Reina, L Wackeroth, D TI Associated Higgs boson production with top quarks at the CERN Large Hadron Collider: NLO QCD corrections SO PHYSICAL REVIEW D LA English DT Article ID ONE-LOOP INTEGRALS; HIGHER-ORDER CORRECTIONS; JET CROSS-SECTIONS; COLLISIONS; ANNIHILATION; LEVEL; MODEL AB We present in detail the calculation of the O(alpha(s)(3)) inclusive total cross section for the process pp-->t (t) over barh, in the standard model, at the CERN Large Hadron Collider with a center-of-mass energy roots(H)=14 TeV. The calculation is based on the complete set of virtual and real O(alpha(s)) corrections to the parton level processes q (q) over bar -->t (t) over barh and gg-->t (t) over barh, as well as the tree level processes (q,(q) over bar )g-->t (t) over barh+(q,(q) over bar). The virtual corrections involve the computation of pentagon diagrams with several internal and external massive particles, first encountered in this process. The real corrections are computed using both the single and the two cutoff phase space slicing method. The next-to-leading order QCD corrections significantly reduce the renormalization and factorization scale dependence of the Born cross section and moderately increase the Born cross section for values of the renormalization and factorization scales above m(t). C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA. RP Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM dawson@quark.phy.bnl.gov; jackson@hep.fsu.edu; orr@pas.rochester.edu; reina@hep.fsu.edu; dow@ubpheno.physics.buffalo.edu NR 46 TC 130 Z9 130 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 034022 DI 10.1103/PhysRevD.68.034022 PG 39 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600046 ER PT J AU Detmold, W Melnitchouk, W Thomas, AW AF Detmold, W Melnitchouk, W Thomas, AW TI Parton distribution functions in the pion from lattice QCD SO PHYSICAL REVIEW D LA English DT Article ID CHIRAL PERTURBATION-THEORY; DRELL-YAN; TWIST-2 OPERATORS; PHOTON PRODUCTION; MATRIX-ELEMENTS; FORM-FACTOR; NJL MODEL; NUCLEON; HERA; PHENOMENOLOGY AB We analyze the moments of parton distribution functions in the pion calculated in lattice QCD, paying particular attention to their chiral extrapolation. Using the lowest three nontrivial moments calculated on the lattice, we assess the accuracy with which the x dependence of both the valence and sea quark distributions in the pion can be extracted. The resulting valence quark distributions at the physical pion mass are in fair agreement with existing Drell-Yan data, but the statistical errors are such that one cannot yet confirm (or rule out) the large-x behavior expected from hadron helicity conservation in perturbative QCD. However, one can expect that the next generation of calculations in lattice QCD will allow one to extract parton distributions with a level of accuracy comparable with current experiments. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Jefferson Lab, Newport News, VA 23606 USA. Univ Adelaide, Dept Phys & Math Phys, Adelaide, SA 5005, Australia. Univ Adelaide, Special Res Ctr Subatom Struct Matter, Adelaide, SA 5005, Australia. RP Univ Washington, Dept Phys, Box 351560, Seattle, WA 98195 USA. RI Thomas, Anthony/G-4194-2012; OI Thomas, Anthony/0000-0003-0026-499X; Detmold, William/0000-0002-0400-8363 NR 58 TC 29 Z9 29 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 034025 DI 10.1103/PhysRevD.68.034025 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600049 ER PT J AU Digal, S Fortunato, S Petreczky, P AF Digal, S Fortunato, S Petreczky, P TI Heavy quark free energies and screening in SU(2) gauge theory SO PHYSICAL REVIEW D LA English DT Article ID STATIC CORRELATION LENGTHS; ADJOINT HIGGS-MODEL; HIGH-TEMPERATURE; GLUON PROPAGATOR; POLYAKOV LOOP; QCD; POTENTIALS; SPECTRUM; DENSITY; MASSES AB We study the properties of the free energy of an infinitely heavy quark-antiquark pair in SU(2) gauge theory. By means of lattice Monte Carlo simulations we calculated the free energies in the singlet, triplet, and color averaged channels, both in the confinement and deconfinement phases. The singlet and triplet free energies are defined in the Coulomb gauge which is equivalent to their gauge invariant definitions recently introduced by Philipsen. We analyze the short and the long distance behavior, making comparisons with the zero temperature case. The temperature dependence of the electric screening mass is carefully investigated. The order of the deconfining transition is manifest in the results near T-c and it allows a reliable test of a recently proposed method to renormalize the Polyakov loop. C1 Univ Bielefeld, Fak Phys, D-33501 Bielefeld, Germany. Brookhaven Natl Lab, Dept Phys, Nucl Theory Grp, Upton, NY 11973 USA. RP Univ Bielefeld, Fak Phys, D-33501 Bielefeld, Germany. RI Fortunato, Santo/C-3586-2009 NR 39 TC 41 Z9 41 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 034008 DI 10.1103/PhysRevD.68.034008 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600032 ER PT J AU Long, O Baak, M Cahn, RN Kirkby, D AF Long, O Baak, M Cahn, RN Kirkby, D TI Impact of tag-side interference on time-dependent CP asymmetry measurements using coherent B-0(B)over-bar(0) pairs SO PHYSICAL REVIEW D LA English DT Article ID INFORMATION; VIOLATION; DECAYS AB Interference between Cabibbo-Kobayashi-Maskawa (CKM) favored b-->c (u) over bard and doubly-CKM-suppressed (b) over bar -->(u) over barc (d) over bar amplitudes in final states used for B-flavor tagging gives deviations from the standard time evolution assumed in CP-violation measurements at B factories producing coherent B-0(B) over bar (0) pairs. We evaluate these deviations for the standard time-dependent CP-violation measurements, the uncertainties they introduce in the measured quantities, and give suggestions for minimizing them. The uncertainty in the measured CP asymmetry for CP eigenstates is approximate to2% or less. The time-dependent analysis of D*pi, proposed for measuring sin(2beta+gamma), must incorporate possible tag-side interference, which could produce asymmetries as large as the expected signal asymmetry. C1 Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. NIKHEF, Natl Inst Nucl & High Energy Phys, NL-1009 DB Amsterdam, Netherlands. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Irvine, Irvine, CA 92697 USA. RP Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. NR 19 TC 100 Z9 98 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 034010 DI 10.1103/PhysRevD.68.034010 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600034 ER PT J AU Mihaila, B AF Mihaila, B TI Real-time dynamics of the O(N) model in 1+1 dimensions SO PHYSICAL REVIEW D LA English DT Article ID APPROXIMATIONS; EVOLUTION AB We study the nonequilibrium dynamics of the O(N) model in classical and quantum field theory in 1+1 dimensions, for N>1. We compare numerical results obtained using the Hartree approximation and two next to leading order approximations: the bare vertex approximation and the two-particle irreducible 1/N expansion. The latter approximations differ through terms of order g(2), where g is the scaled coupling constant, g=lambda/N. In this paper we investigate the statement regarding the convergence with respect to g. The differences between these two approximation schemes are computed and found to be already small for relatively small values of N, when lambda is fixed. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. EM bmihaila@lanl.gov RI Mihaila, Bogdan/D-8795-2013 OI Mihaila, Bogdan/0000-0002-1489-8814 NR 21 TC 13 Z9 13 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 036002 DI 10.1103/PhysRevD.68.036002 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600075 ER PT J AU Murakami, B Wells, JD AF Murakami, B Wells, JD TI Abelian D terms and the superpartner spectrum of anomaly-mediated supersymmetry breaking SO PHYSICAL REVIEW D LA English DT Article AB We address the tachyonic slepton problem of anomaly mediated supersymmetry breaking using Abelian D terms. We demonstrate that the most general extra U(1) symmetry that does not disrupt gauge coupling unification has a large set of possible charges that solves the problem. It is shown that previous studies in this direction that added both an extra hypercharge D-term and another D-term induced by B-L symmetry (or similar) can be mapped into a single D-term of the general ancillary U(1)(a). The U(1)(a) formalism enables identifying the sign of squark mass corrections which leads to an upper bound of the entire superpartner spectrum given knowledge of just one superpartner mass. C1 Argonne Natl Lab, HEP Div, Argonne, IL 60439 USA. Univ Michigan, Dept Phys, MCTP, Ann Arbor, MI 48109 USA. RP Argonne Natl Lab, HEP Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 21 TC 26 Z9 26 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD AUG 1 PY 2003 VL 68 IS 3 AR 035006 DI 10.1103/PhysRevD.68.035006 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 719FU UT WOS:000185193600062 ER PT J AU Nayak, GC Liu, MX Cooper, F AF Nayak, GC Liu, MX Cooper, F TI Color octet contribution to high p(T) J/psi production in pp collisions at root s=500 and 200 GeV at BNL RHIC SO PHYSICAL REVIEW D LA English DT Article ID FIXED TARGET ENERGIES; J-PSI; QUARKONIA PRODUCTION; UPSILON-PRODUCTION; FERMILAB-TEVATRON; HEAVY QUARKONIUM; FRAGMENTATION; PLASMA; HADROPRODUCTION; PHOTOPRODUCTION AB We compute dsigma/dp(T) of the J/psi production in pp collisions at BNL RHIC at roots=500 and 200 GeV by using both the color octet and singlet models in the framework of nonrelativistic QCD. The J/psi we compute here includes the direct J/psi from the partonic fusion processes and the J/psi coming from the radiative decays of chi(J)'s both in the color octet and singlet channel. The high p(T) J/psi production cross section is computed within the PHENIX detector acceptance ranges: -0.35pi(+)pi(-)pi(+))=(10.9 +/- 3.3 +/- 1.6)x10(-6), B(B+-> K+pi(-)pi(+))=(59.1 +/- 3.8 +/- 3.2)x10(-6), and B(B+-> K+K-K+)=(29.6 +/- 2.1 +/- 1.6)x10(-6) and provide 90% C.L. upper limits for other decays. We observe no charge asymmetries for these modes. C1 Phys Particules Lab, F-74941 Annecy Le Vieux, France. Univ Bari, Dipartmento Fis, I-70126 Bari, Italy. Ist Nazl Fis Nucl, I-70126 Bari, Italy. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Bergen, Inst Phys, N-5007 Bergen, Norway. Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Ruhr Univ Bochum, Inst Expt Phys 1, D-44780 Bochum, Germany. Univ Bristol, Bristol BS8 1TL, Avon, England. Univ British Columbia, Vancouver, BC V6T 1Z1, Canada. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. CALTECH, Pasadena, CA 91125 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Colorado, Boulder, CO 80309 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Tech Univ Dresden, Inst Kern & Teilchenphys, D-01062 Dresden, Germany. Ecole Polytech, LLR, F-91128 Palaiseau, France. Univ Edinburgh, Edinburgh EH9 3JZ, Midlothian, Scotland. Univ Ferrara, Dipartmento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, I-44100 Ferrara, Italy. Florida A&M Univ, Tallahassee, FL 32307 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy. Ist Nazl Fis Nucl, I-16146 Genoa, Italy. Harvard Univ, Cambridge, MA 02138 USA. Univ Iowa, Iowa City, IA 52242 USA. Iowa State Univ, Ames, IA 50011 USA. Lab Accelerateur Lineaire, F-91898 Orsay, France. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. Univ London Imperial Coll Sci Technol & Med, London SW7 2BW, England. Univ London, Queen Mary, London E1 4NS, England. Univ London Royal Holloway & Bedford New Coll, Egham TW20 0EX, Surrey, England. Univ Louisville, Louisville, KY 40292 USA. Univ Manchester, Manchester M13 9PL, Lancs, England. Univ Maryland, College Pk, MD 20742 USA. Univ Massachusetts, Amherst, MA 01003 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. McGill Univ, Montreal, PQ H3A 2T8, Canada. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Ist Nazl Fis Nucl, I-20133 Milan, Italy. Univ Mississippi, University, MS 38677 USA. Univ Montreal, Lab Rene JA Levesque, Montreal, PQ H3C 3J7, Canada. Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Naples Federico II, Dipartimento Sci Fis, I-80126 Naples, Italy. Ist Nazl Fis Nucl, I-80126 Naples, Italy. NIKHEF, Natl Inst Nucl Phys & High Energy Phys, NL-1009 DB Amsterdam, Netherlands. Univ Notre Dame, Notre Dame, IN 46556 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Padua, Dipartimento Fis, I-35131 Padua, Italy. Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Paris 06, Lab Phys Nucl HE, F-75252 Paris, France. Univ Paris 07, Lab Phys Nucl HE, F-75252 Paris, France. Univ Pavia, Dipartimento Elettron, I-27100 Pavia, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Dipartimento Fis, Scuola Normale Super Pisa, I-56127 Pisa, Italy. Ist Nazl Fis Nucl, I-56127 Pisa, Italy. Prairie View A&M Univ, Prairie View, TX 77446 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Univ Rostock, D-18051 Rostock, Germany. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CEA Saclay, DAPNIA, F-91191 Gif Sur Yvette, France. Univ S Carolina, Columbia, SC 29208 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Stanford, CA 94305 USA. SUNY Albany, Albany, NY 12222 USA. Univ Tennessee, Knoxville, TN 37996 USA. Univ Texas, Austin, TX 78712 USA. Univ Texas, Richardson, TX 75083 USA. Univ Turin, Dipartimento Fis Sperimentale, I-10125 Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Trieste, Dipartmento Fis, I-34127 Trieste, Italy. Ist Nazl Fis Nucl, I-34127 Trieste, Italy. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Victoria, Victoria, BC V8W 3P6, Canada. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. Univ Perugia, I-06100 Perugia, Italy. Univ Basilicata, I-85100 Potenza, Italy. Univ Valencia, CSIC, Inst Fis Corpuscular, IFIC, Valencia, Spain. RP Aubert, B (reprint author), Phys Particules Lab, F-74941 Annecy Le Vieux, France. RI Lo Vetere, Maurizio/J-5049-2012; Grancagnolo, Sergio/J-3957-2015; Lusiani, Alberto/N-2976-2015; Morandin, Mauro/A-3308-2016; Lusiani, Alberto/A-3329-2016; Della Ricca, Giuseppe/B-6826-2013; Di Lodovico, Francesca/L-9109-2016; Calcaterra, Alessandro/P-5260-2015; Frey, Raymond/E-2830-2016; Bellini, Fabio/D-1055-2009; de Groot, Nicolo/A-2675-2009; Neri, Nicola/G-3991-2012; Rotondo, Marcello/I-6043-2012; Lista, Luca/C-5719-2008; Cavallo, Nicola/F-8913-2012; Forti, Francesco/H-3035-2011; Monge, Maria Roberta/G-9127-2012; Peters, Klaus/C-2728-2008; Kravchenko, Evgeniy/F-5457-2015; Mir, Lluisa-Maria/G-7212-2015; Martinez Vidal, F*/L-7563-2014; Kolomensky, Yury/I-3510-2015; de Sangro, Riccardo/J-2901-2012; Sarti, Alessio/I-2833-2012; Patrignani, Claudia/C-5223-2009 OI Lo Vetere, Maurizio/0000-0002-6520-4480; Grancagnolo, Sergio/0000-0001-8490-8304; Lusiani, Alberto/0000-0002-6876-3288; Morandin, Mauro/0000-0003-4708-4240; Lusiani, Alberto/0000-0002-6876-3288; Della Ricca, Giuseppe/0000-0003-2831-6982; Di Lodovico, Francesca/0000-0003-3952-2175; Calcaterra, Alessandro/0000-0003-2670-4826; Frey, Raymond/0000-0003-0341-2636; Bellini, Fabio/0000-0002-2936-660X; Neri, Nicola/0000-0002-6106-3756; Rotondo, Marcello/0000-0001-5704-6163; Forti, Francesco/0000-0001-6535-7965; Monge, Maria Roberta/0000-0003-1633-3195; Peters, Klaus/0000-0001-7133-0662; Mir, Lluisa-Maria/0000-0002-4276-715X; Martinez Vidal, F*/0000-0001-6841-6035; Kolomensky, Yury/0000-0001-8496-9975; de Sangro, Riccardo/0000-0002-3808-5455; Sarti, Alessio/0000-0001-5419-7951; Patrignani, Claudia/0000-0002-5882-1747 NR 10 TC 96 Z9 96 U1 0 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD AUG 1 PY 2003 VL 91 IS 5 AR 051801 DI 10.1103/PhysRevLett.91.051801 PG 7 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600005 PM 14611333 ER PT J AU Back, BB Baker, MD Barton, DS Betts, RR Ballintijn, M Bickley, AA Bindel, R Budzanowski, A Busza, W Carroll, A Decowski, MP Garcia, E George, N Gulbrandsen, K Gushue, S Halliwell, C Hamblen, J Heintzelman, GA Henderson, C Hofman, DJ Hollis, RS Holynski, R Holzman, B Iordanova, A Johnson, E Kane, JL Katzy, J Khan, N Kucewicz, W Kulinich, P Kuo, CM Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, AC Nouicer, R Olszewski, A Pak, R Park, IC Pernegger, H Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Rosenberg, L Sagerer, J Sarin, P Sawicki, P Skulski, W Steadman, SG Steinberg, P Stephans, GSF Stodulski, M Sukhanov, A Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B AF Back, BB Baker, MD Barton, DS Betts, RR Ballintijn, M Bickley, AA Bindel, R Budzanowski, A Busza, W Carroll, A Decowski, MP Garcia, E George, N Gulbrandsen, K Gushue, S Halliwell, C Hamblen, J Heintzelman, GA Henderson, C Hofman, DJ Hollis, RS Holynski, R Holzman, B Iordanova, A Johnson, E Kane, JL Katzy, J Khan, N Kucewicz, W Kulinich, P Kuo, CM Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, AC Nouicer, R Olszewski, A Pak, R Park, IC Pernegger, H Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Rosenberg, L Sagerer, J Sarin, P Sawicki, P Skulski, W Steadman, SG Steinberg, P Stephans, GSF Stodulski, M Sukhanov, A Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B TI Significance of the fragmentation region in ultrarelativistic heavy-ion collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID PB-PB COLLISIONS; HIGH-ENERGY; PSEUDORAPIDITY DISTRIBUTIONS; PARTICLE; SCATTERING; NUCLEON AB We present measurements of the pseudorapidity distribution of primary charged particles produced in Au+Au collisions at three energies, roots(NN) = 19.6, 130, and 200 GeV, for a range of collision centralities. The distribution narrows for more central collisions and excess particles are produced at high pseudorapidity in peripheral collisions. For a given centrality, however, the distributions are found to scale with energy according to the "limiting fragmentation" hypothesis. The universal fragmentation region described by this scaling grows in pseudorapidity with increasing collision energy, extending well away from the beam rapidity and covering more than half of the pseudorapidity range over which particles are produced. This approach to a universal limiting curve appears to be a dominant feature of the pseudorapidity distribution and therefore of the total particle production in these collisions. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, CA Dept, Upton, NY 11973 USA. Inst Nucl Phys, Krakow, Poland. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. Natl Cent Univ, Dept Phys, Chungli 32054, Taiwan. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Univ Maryland, Dept Chem, College Pk, MD 20742 USA. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. RP Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RI Decowski, Patrick/A-4341-2011; Mignerey, Alice/D-6623-2011; OI Reuter, Michael/0000-0003-3881-8310; Holzman, Burt/0000-0001-5235-6314 NR 21 TC 241 Z9 246 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD AUG 1 PY 2003 VL 91 IS 5 AR 052303 DI 10.1103/PhysRevLett.91.052303 PG 4 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600009 PM 12906591 ER PT J AU Bass, SA Muller, B Srivastava, DK AF Bass, SA Muller, B Srivastava, DK TI Net baryon density in Au plus Au collisions at the relativistic heavy ion collider SO PHYSICAL REVIEW LETTERS LA English DT Article ID ULTRARELATIVISTIC NUCLEAR COLLISIONS; CHARGED-PARTICLE DISTRIBUTIONS; TRANSVERSE-MOMENTUM; HADRON-PRODUCTION; PARTON-CASCADES; STOPPING POWER; SMALL-X; QCD; ENERGY; NUMBER AB We calculate the net-baryon rapidity distribution in Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC) in the framework of the parton cascade model (PCM). Parton rescattering and fragmentation leads to a substantial increase in the net-baryon density at midrapidity over the density produced by initial primary parton-parton scatterings. The PCM is able to describe the measured net-baryon density at RHIC. C1 Duke Univ, Dept Phys, Durham, NC 27708 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. Bhabha Atom Res Ctr, Ctr Variable Energy Cyclotron, Kolkata 700064, W Bengal, India. McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. RP Bass, SA (reprint author), Duke Univ, Dept Phys, Durham, NC 27708 USA. OI Bass, Steffen/0000-0002-9451-0954 NR 48 TC 44 Z9 45 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD AUG 1 PY 2003 VL 91 IS 5 AR 052302 DI 10.1103/PhysRevLett.91.052302 PG 4 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600008 PM 12906590 ER PT J AU Blum, T AF Blum, T TI Lattice calculation of the lowest-order hadronic contribution to the muon anomalous magnetic moment SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHIRAL FERMIONS; POLARIZATION AB We present a quenched lattice calculation of the lowest order [O(alpha(2))] hadronic contribution to the anomalous magnetic moment of the muon which arises from the hadronic vacuum polarization. A general method is presented for computing entirely in Euclidean space, obviating the need for the usual dispersive treatment which relies on experimental data for e(+)e(-) annihilation to hadrons. While the result is not yet of comparable precision to those state-of-the-art calculations, systematic improvement of the quenched lattice computation to this level is straightforward and well within the reach of present computers. Including the effects of dynamical quarks is conceptually trivial; the computer resources required are not. C1 Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Blum, T (reprint author), Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. NR 20 TC 79 Z9 79 U1 0 U2 0 PU AMERICAN 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 AUG 1 PY 2003 VL 91 IS 5 AR 052001 DI 10.1103/PhysRevLett.91.052001 PG 4 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600006 PM 12906588 ER PT J AU Carlson, J Chang, SY Pandharipande, VR Schmidt, KE AF Carlson, J Chang, SY Pandharipande, VR Schmidt, KE TI Superfluid Fermi gases with large scattering length SO PHYSICAL REVIEW LETTERS LA English DT Article ID STATE AB We report quantum Monte Carlo calculations of superfluid Fermi gases with short-range two-body attractive interactions with infinite scattering length. The energy of such gases is estimated to be (0.44+/-0.01) times that of the noninteracting gas, and their pairing gap is approximately twice the energy per particle. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. RP Carlson, J (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 16 TC 427 Z9 428 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD AUG 1 PY 2003 VL 91 IS 5 AR 050401 DI 10.1103/PhysRevLett.91.050401 PG 4 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600001 PM 12906583 ER PT J AU Feibelman, PJ AF Feibelman, PJ TI Comment on "Vibrational recognition of hydrogen-bonded water networks on a metal surface" SO PHYSICAL REVIEW LETTERS LA English DT Editorial Material ID TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; MOLECULAR-DYNAMICS; PT(111); ICE C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Feibelman, PJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 28 Z9 28 U1 1 U2 4 PU AMERICAN 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 AUG 1 PY 2003 VL 91 IS 5 AR 059601 DI 10.1103/PhysRevLett.91.059601 PG 1 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600062 PM 12906644 ER PT J AU Hemmers, O Guillemin, R Kanter, EP Krassig, B Lindle, DW Southworth, SH Wehlitz, R Baker, J Hudson, A Lotrakul, M Rolles, D Stolte, WC Tran, IC Wolska, A Yu, SW Amusia, MY Cheng, KT Chernysheva, LV Johnson, WR Manson, ST AF Hemmers, O Guillemin, R Kanter, EP Krassig, B Lindle, DW Southworth, SH Wehlitz, R Baker, J Hudson, A Lotrakul, M Rolles, D Stolte, WC Tran, IC Wolska, A Yu, SW Amusia, MY Cheng, KT Chernysheva, LV Johnson, WR Manson, ST TI Dramatic nondipole effects in low-energy photoionization: Experimental and theoretical study of Xe 5s SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHOTOELECTRON ANGULAR-DISTRIBUTIONS; PHOTO-IONIZATION; DISTRIBUTION PARAMETERS; MULTIPOLE CORRECTIONS; DIPOLE APPROXIMATION; CROSS-SECTIONS; NOBLE-GASES; SUBSHELL; XENON; RETARDATION AB The Xe 5s nondipole photoelectron parameter gamma is obtained experimentally and theoretically from threshold to similar to200 eV photon energy. Significant nondipole effects are seen even in the threshold region of this valence shell photoionization. In addition, contrary to previous understanding, clear evidence of interchannel coupling among quadrupole photoionization channels is found. C1 Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Wisconsin, Ctr Synchrotron Radiat, Stoughton, WI 53589 USA. Max Planck Gesell, Fritz Haber Inst, D-1000 Berlin, Germany. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Georgia State Univ, Dept Phys & Astron, Atlanta, GA 30303 USA. RP Hemmers, O (reprint author), Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. RI Rolles, Daniel/C-2384-2008; Wolska, Anna/A-5818-2012; Tran, Ich/C-9869-2014; Chernysheva, Larissa/E-5916-2014; Amusia, Miron/K-7726-2014 NR 38 TC 41 Z9 41 U1 1 U2 7 PU AMERICAN 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 AUG 1 PY 2003 VL 91 IS 5 AR 053002 DI 10.1103/PhysRevLett.91.053002 PG 4 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600011 PM 12906593 ER PT J AU Strauch, S Dieterich, S Aniol, KA Annand, JRM Baker, OK Bertozzi, W Boswell, M Brash, EJ Chai, Z Chen, JP Christy, ME Chudakov, E Cochran, A De Leo, R Ent, R Epstein, MB Finn, JM Fissum, KG Forest, TA Frullani, S Garibaldi, F Gasparian, A Gayou, O Gilad, S Gilman, R Glashausser, C Gomez, J Gorbenko, V Gueye, PLJ Hansen, JO Higinbotham, DW Hu, B Hyde-Wright, CE Ireland, DG Jackson, C de Jager, CW Jiang, X Jones, C Jones, MK Kellie, JD Kelly, JJ Keppel, CE Kumbartzki, G Kuss, M LeRose, JJ Livingston, K Liyanage, N Malov, S Margaziotis, DJ Meekins, D Michaels, R Mitchell, JH Nanda, SK Nappa, J Perdrisat, CF Punjabi, VA Ransome, RD Roche, R Rosner, G Rvachev, M Sabatie, F Saha, A Sarty, A Udias, JM Ulmer, PE Urciuoli, GM van den Brand, JFJ Vignote, JR Watts, DP Weinstein, LB Wijesooriya, K Wojtsekhowski, B AF Strauch, S Dieterich, S Aniol, KA Annand, JRM Baker, OK Bertozzi, W Boswell, M Brash, EJ Chai, Z Chen, JP Christy, ME Chudakov, E Cochran, A De Leo, R Ent, R Epstein, MB Finn, JM Fissum, KG Forest, TA Frullani, S Garibaldi, F Gasparian, A Gayou, O Gilad, S Gilman, R Glashausser, C Gomez, J Gorbenko, V Gueye, PLJ Hansen, JO Higinbotham, DW Hu, B Hyde-Wright, CE Ireland, DG Jackson, C de Jager, CW Jiang, X Jones, C Jones, MK Kellie, JD Kelly, JJ Keppel, CE Kumbartzki, G Kuss, M LeRose, JJ Livingston, K Liyanage, N Malov, S Margaziotis, DJ Meekins, D Michaels, R Mitchell, JH Nanda, SK Nappa, J Perdrisat, CF Punjabi, VA Ransome, RD Roche, R Rosner, G Rvachev, M Sabatie, F Saha, A Sarty, A Udias, JM Ulmer, PE Urciuoli, GM van den Brand, JFJ Vignote, JR Watts, DP Weinstein, LB Wijesooriya, K Wojtsekhowski, B TI Polarization transfer in the He-4((e)over-right-arrow,e '(p)over-right-arrow)H-3 reaction up to Q(2)=2.6 (GeV/c)(2) SO PHYSICAL REVIEW LETTERS LA English DT Article ID COULOMB SUM-RULE; IMPULSE APPROXIMATION; RESPONSE FUNCTIONS; LONGITUDINAL RESPONSE; REACTION C-12(E,E'P); NUCLEUS SCATTERING; BOUND NUCLEONS; FORM-FACTORS; DEPENDENCE; HE-4 AB We have measured the proton recoil polarization in the He-4((e) over right arrow ,e(')(p) over right arrow)H-4 reaction at Q(2)=0.5, 1.0, 1.6, and 2.6 (GeV/c)(2). The measured ratio of polarization transfer coefficients differs from a fully relativistic calculation, favoring the inclusion of a medium modification of the proton form factors predicted by a quark-meson coupling model. In addition, the measured induced polarizations agree reasonably well with the fully relativistic calculation indicating that the treatment of final-state interactions is under control. C1 Rutgers State Univ, Piscataway, NJ 08854 USA. Calif State Univ Los Angeles, Los Angeles, CA 90032 USA. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Hampton Univ, Hampton, VA 23668 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. MIT, Cambridge, MA 02139 USA. Randolph Macon Womans Coll, Lynchburg, VA 24503 USA. Univ Regina, Regina, SK S4S 0A2, Canada. Univ Bari, I-70126 Bari, Italy. Ist Nazl Fis Nucl, Sez Bari, I-70126 Bari, Italy. Coll William & Mary, Williamsburg, VA 23187 USA. Lund Univ, SE-22100 Lund, Sweden. Old Dominion Univ, Norfolk, VA 23529 USA. Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. Ist Super Sanita, Fis Lab, I-00161 Rome, Italy. Univ Clermont Ferrand, F-63177 Clermont Ferrand, France. Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. Univ Maryland, College Pk, MD 20742 USA. Florida State Univ, Tallahassee, FL 32306 USA. Norfolk State Univ, Norfolk, VA 23504 USA. Univ Complutense Madrid, E-28040 Madrid, Spain. Vrije Univ Amsterdam, NL-1081 HV Amsterdam, Netherlands. Univ Illinois, Urbana, IL 61801 USA. RP Strauch, S (reprint author), George Washington Univ, Dept Phys, Washington, DC 20052 USA. RI Ireland, David/E-8618-2010; Udias, Jose/A-7523-2010; Kuss, Michael/H-8959-2012; Sarty, Adam/G-2948-2014; Sabatie, Franck/K-9066-2015 OI Ireland, David/0000-0001-7713-7011; Udias, Jose/0000-0003-3714-764X; Sabatie, Franck/0000-0001-7031-3975 NR 40 TC 87 Z9 87 U1 0 U2 2 PU AMERICAN 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 AUG 1 PY 2003 VL 91 IS 5 AR 052301 DI 10.1103/PhysRevLett.91.052301 PG 5 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600007 PM 12906589 ER PT J AU van Gastel, R Plass, R Bartelt, NC Kellogg, GL AF van Gastel, R Plass, R Bartelt, NC Kellogg, GL TI Thermal motion and energetics of self-assembled domain structures: Pb on Cu(111) SO PHYSICAL REVIEW LETTERS LA English DT Article ID LABYRINTHINE PATTERN-FORMATION; PHASE-TRANSITIONS; COMPETING INTERACTIONS; CRYSTAL-SURFACES; LIPID MONOLAYERS; MAGNETIC FLUIDS; SOLID-SURFACES; NANOSTRUCTURES; GROWTH; THERMODYNAMICS AB Low energy electron microscope measurements of the thermal motion of 50-200 nm diameter Pb islands on Cu(111) are used to establish the nature and determine the strength of interactions that give rise to self-assembly in this two-dimensional, two-phase system. The results show that self-assembled patterns arise from a temperature-independent surface stress difference of approximately 1.2 N/m between the two phases. With increasing Pb coverage, the domain patterns evolve in a manner consistent with models based on dipolar repulsions caused by elastic interactions due to a surface stress difference. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP van Gastel, R (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Bartelt, Norman/G-2927-2012 NR 38 TC 32 Z9 32 U1 1 U2 10 PU AMERICAN 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 AUG 1 PY 2003 VL 91 IS 5 AR 055503 DI 10.1103/PhysRevLett.91.055503 PG 4 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600023 PM 12906605 ER PT J AU Wang, LW Califano, M Zunger, A Franceschetti, A AF Wang, LW Califano, M Zunger, A Franceschetti, A TI Pseudopotential theory of Auger processes in CdSe quantum dots SO PHYSICAL REVIEW LETTERS LA English DT Article ID SEMICONDUCTOR NANOCRYSTALLITES; ELECTRON RELAXATION; PHONON BOTTLENECK; RECOMBINATION; LUMINESCENCE; INP AB Auger rates are calculated for CdSe colloidal quantum dots using atomistic empirical pseudopotential wave functions. We predict the dependence of Auger electron cooling on size, on correlation effects (included via configuration interaction), and on the presence of a spectator exciton. Auger multiexciton recombination rates are predicted for biexcitons as well as for triexcitons. The results agree quantitatively with recent measurements and offer new predictions. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Wang, LW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. RI Zunger, Alex/A-6733-2013 NR 22 TC 144 Z9 144 U1 5 U2 35 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 AUG 1 PY 2003 VL 91 IS 5 AR 056404 DI 10.1103/PhysRevLett.91.056404 PG 4 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600032 ER PT J AU Zhu, JX Ahn, KH Nussinov, Z Lookman, T Balatsky, AV Bishop, AR AF Zhu, JX Ahn, KH Nussinov, Z Lookman, T Balatsky, AV Bishop, AR TI Elasticity-driven nanoscale electronic structure in superconductors SO PHYSICAL REVIEW LETTERS LA English DT Article ID D-WAVE SUPERCONDUCTORS; TIME-REVERSAL-SYMMETRY; T-C SUPERCONDUCTORS; II SUPERCONDUCTOR; ORDER PARAMETERS; VORTEX LINE; STATES; SURFACE; IMPURITY; YBA2CU3O7-DELTA AB The effects of long-range anisotropic elastic deformations on electronic structure in superconductors are analyzed within the framework of the Bogoliubov-de Gennes equations. Cases of twin boundaries and isolated defects are considered as illustrations. We find that the superconducting order parameter is depressed in the regions where pronounced lattice-deformation occurs. The calculated local density of states suggests that the electronic structure is strongly modulated in response to lattice deformations, and propagates to longer distances. In particular, this allows the trapping of low-lying quasiparticle states around defects. Some of our predictions can be directly tested by scanning tunneling microscopy experiments. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 27 TC 22 Z9 22 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD AUG 1 PY 2003 VL 91 IS 5 AR 057004 DI 10.1103/PhysRevLett.91.057004 PG 4 WC Physics, Multidisciplinary SC Physics GA 707KV UT WOS:000184510600044 PM 12906626 ER PT J AU Alsharo'a, MM Ankenbrandt, CM Atac, M Autin, BR Balbekov, VI Barger, VD Benary, O Bennett, JRJ Berger, MS Berg, JS Berz, M Black, EL Blondel, A Bogacz, SA Bonesini, M Bracker, SB Bross, AD Bruno, L Buckley-Geer, EJ Caldwell, AC Campanelli, M Cassel, KW Catanesi, MG Chattopadhyay, S Chou, WR Cline, DB Coney, LR Conrad, JM Corlett, JN Cremaldi, L Cummings, MA Darve, C DeJongh, F Drozhdin, A Drumm, P Elvira, VD Errede, D Fabich, A Fawley, WM Fernow, RC Ferrario, M Finley, DA Fisch, NJ Fukui, Y Furman, MA Gabriel, TA Galea, R Gallardo, JC Garoby, R Garren, AA Geer, SH Gilardoni, S Van Ginneken, AJ Ginzburg, IF Godang, R Goodman, M Gosz, MR Green, MA Gruber, P Gunion, JF Gupta, R Haines, JR Hanke, K Hanson, GG Han, T Haney, M Hartill, D Hartline, RE Haseroth, HD Hassanein, A Hoffman, K Holtkamp, N Holzer, EB Johnson, C Johnson, RP Johnstone, C Jungmann, K Kahn, SA Kaplan, DM Keil, EK Kim, ES Kim, KJ King, BJ Kirk, HG Kuno, Y Ladran, TS Lau, WW Learned, JG Lebedev, V Lebrun, P Lee, K Lettry, JA Laveder, M Li, DR Lombardi, A Lu, CG Makino, K Malkin, V Marfatia, D McDonald, KT Mezzetto, M Miller, JR Mills, FE Mocioiu, I Mokhov, NV Monroe, J Moretti, A Mori, Y Neuffer, DV Ng, KY Norem, JH Onel, Y Oreglia, M Ozaki, S Padamsee, H Pakvasa, S Palmer, RB Parker, B Parsa, Z Penn, G Pischalnikov, Y Popovic, MB Qian, ZB Radicioni, E Raja, R Ravn, HL Reed, CB Reginato, LL Rehak, P Rimmer, RA Roberts, TJ Roser, T Rossmanith, R Samulyak, RV Scanlan, RM Schlenstedt, S Schwandt, P Sessler, AM Shaevitz, MH Shrock, R Sievers, P Silvestrov, GI Simos, N Skrinsky, AN Solomey, N Spampinato, PT Spentzouris, P Stefanski, R Stoltz, P Stumer, I Summers, DJ Teng, LC Thieberger, PA Tigner, M Todosow, M Tollestrup, AV Torun, Y Trbojevic, D Usubov, ZU Vsevolozhskaya, TA Wah, Y Wang, CX Wang, HP Weggel, RJ Whisnant, K Willen, EH Wilson, EJN Winn, DR Wurtele, JS Wu, V Yokoi, T Yoon, M York, R Yu, S Zeller, A Zhao, YX Zisman, MS AF Alsharo'a, MM Ankenbrandt, CM Atac, M Autin, BR Balbekov, VI Barger, VD Benary, O Bennett, JRJ Berger, MS Berg, JS Berz, M Black, EL Blondel, A Bogacz, SA Bonesini, M Bracker, SB Bross, AD Bruno, L Buckley-Geer, EJ Caldwell, AC Campanelli, M Cassel, KW Catanesi, MG Chattopadhyay, S Chou, WR Cline, DB Coney, LR Conrad, JM Corlett, JN Cremaldi, L Cummings, MA Darve, C DeJongh, F Drozhdin, A Drumm, P Elvira, VD Errede, D Fabich, A Fawley, WM Fernow, RC Ferrario, M Finley, DA Fisch, NJ Fukui, Y Furman, MA Gabriel, TA Galea, R Gallardo, JC Garoby, R Garren, AA Geer, SH Gilardoni, S Van Ginneken, AJ Ginzburg, IF Godang, R Goodman, M Gosz, MR Green, MA Gruber, P Gunion, JF Gupta, R Haines, JR Hanke, K Hanson, GG Han, T Haney, M Hartill, D Hartline, RE Haseroth, HD Hassanein, A Hoffman, K Holtkamp, N Holzer, EB Johnson, C Johnson, RP Johnstone, C Jungmann, K Kahn, SA Kaplan, DM Keil, EK Kim, ES Kim, KJ King, BJ Kirk, HG Kuno, Y Ladran, TS Lau, WW Learned, JG Lebedev, V Lebrun, P Lee, K Lettry, JA Laveder, M Li, DR Lombardi, A Lu, CG Makino, K Malkin, V Marfatia, D McDonald, KT Mezzetto, M Miller, JR Mills, FE Mocioiu, I Mokhov, NV Monroe, J Moretti, A Mori, Y Neuffer, DV Ng, KY Norem, JH Onel, Y Oreglia, M Ozaki, S Padamsee, H Pakvasa, S Palmer, RB Parker, B Parsa, Z Penn, G Pischalnikov, Y Popovic, MB Qian, ZB Radicioni, E Raja, R Ravn, HL Reed, CB Reginato, LL Rehak, P Rimmer, RA Roberts, TJ Roser, T Rossmanith, R Samulyak, RV Scanlan, RM Schlenstedt, S Schwandt, P Sessler, AM Shaevitz, MH Shrock, R Sievers, P Silvestrov, GI Simos, N Skrinsky, AN Solomey, N Spampinato, PT Spentzouris, P Stefanski, R Stoltz, P Stumer, I Summers, DJ Teng, LC Thieberger, PA Tigner, M Todosow, M Tollestrup, AV Torun, Y Trbojevic, D Usubov, ZU Vsevolozhskaya, TA Wah, Y Wang, CX Wang, HP Weggel, RJ Whisnant, K Willen, EH Wilson, EJN Winn, DR Wurtele, JS Wu, V Yokoi, T Yoon, M York, R Yu, S Zeller, A Zhao, YX Zisman, MS TI Recent progress in neutrino factory and muon collider research within the Muon Collaboration SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Review ID HIGH-PRECISION MEASUREMENTS; ZENITH-ANGLE DISTRIBUTION; MU(+) -> E(+)GAMMA; GEV ENERGY-RANGE; SUPER-KAMIOKANDE; ATMOSPHERIC NEUTRINOS; 3-NEUTRINO OSCILLATIONS; SOLAR NEUTRINOS; PARAMETRIC-RESONANCE; MAGNETIC-MOMENT AB We describe the status of our effort to realize a first neutrino factory and the progress made in understanding the problems associated with the collection and cooling of muons towards that end. We summarize the physics that can be done with neutrino factories as well as with intense cold beams of muons. The physics potential of muon colliders is reviewed, both as Higgs factories and compact high-energy lepton colliders. The status and time scale of our research and development effort is reviewed as well as the latest designs in cooling channels including the promise of ring coolers in achieving longitudinal and transverse cooling simultaneously. We detail the efforts being made to mount an international cooling experiment to demonstrate the ionization cooling of muons. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. IIT, Div Phys, Chicago, IL 60616 USA. CERN, CH-1211 Geneva 23, Switzerland. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ Geneva, DPNC, CH-1211 Geneva 4, Switzerland. Jefferson Lab, Newport News, VA 23606 USA. Univ Mississippi, University, MS 38677 USA. Columbia Univ, Nevis Lab, Irvington, NY 10533 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. No Illinois Univ, De Kalb, IL 60115 USA. Univ Illinois, Urbana, IL 61801 USA. Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Russian Acad Sci, Inst Math, Novosibirsk 630090, Russia. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Cornell Univ, Newman Lab Nucl Studies, Ithaca, NY 14853 USA. Muons Inc, Batavia, IL 60510 USA. Univ Chicago, Chicago, IL 60637 USA. Univ Groningen, Kernfys Versneller Inst, NL-9747 AA Groningen, Netherlands. Pohang Univ Sci & Technol, Pohang, South Korea. Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. Osaka Univ, Osaka 567, Japan. Univ Oxford, Oxford, England. Univ Hawaii, Dept Phys, Honolulu, HI 96822 USA. Princeton Univ, Joseph Henry Labs, Princeton, NJ 08544 USA. Boston Univ, Boston, MA 02215 USA. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11790 USA. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan. Univ Iowa, Iowa City, IA 52242 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Forschungszentrum Karlsruhe, D-76021 Karlsruhe, Germany. DESY Zeuthen, Zeuthen, Germany. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Tech X Corp, Boulder, CO 80301 USA. Iowa State Univ, Ames, IA 50011 USA. Fairfield Univ, Fairfield, CT 06430 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Raja, R (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM raja@fnal.gov RI Jungmann, Klaus/A-7142-2010; jungmann, klaus/H-1581-2013; Berg, Joseph/E-8371-2014; wurtele, Jonathan/J-6278-2016; OI jungmann, klaus/0000-0003-0571-4072; Berg, Joseph/0000-0002-5955-6973; wurtele, Jonathan/0000-0001-8401-0297; Cassel, Kevin/0000-0003-0981-496X; Torun, Yagmur/0000-0003-2336-6585 NR 248 TC 124 Z9 125 U1 2 U2 14 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD AUG PY 2003 VL 6 IS 8 AR 081001 DI 10.1103/PhysRevSTAB.6.081001 PG 52 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 721LV UT WOS:000185318600003 ER PT J AU Delayen, JR AF Delayen, JR TI Cumulative beam breakup in linear accelerators with arbitrary beam current profile SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID INSTABILITIES; COLLIDERS AB An analytical formalism for the solution of cumulative beam breakup in linear accelerators with arbitrary time dependence of beam current is presented, and a closed-form expression for the time and position dependence of the transverse displacement is obtained. It is applied to the behavior of a single bunch and to the steady-state and transient behavior of dc beams and beams composed of pointlike and finite-length bunches. This formalism is also applied to the problem of cumulative beam breakup in the presence of random displacement of cavities and focusing elements, and a general solution is presented. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Delayen, JR (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. EM delayen@jlab.org NR 23 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 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD AUG PY 2003 VL 6 IS 8 AR 084402 DI 10.1103/PhysRevSTAB.6.084402 PG 17 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 721LV UT WOS:000185318600008 ER PT J AU Heifets, S AF Heifets, S TI Single-mode coherent synchrotron radiation instability of a bunched beam SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB The coherent synchrotron radiation instability may be driven at the shielding threshold by a single mode excited in the beam pipe. Such a problem may have general interest for other one-mode dominated problems arising in plasma, free-electron laser theory, and microwave instability. The problem may have practical interest if the steady state exists but requires the study of the nonlinear regime of instability. The results of the study, both analytic and numerical, are presented in the coasting beam approximation and for a bunched beam. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Heifets, S (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 4 TC 6 Z9 6 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD AUG PY 2003 VL 6 IS 8 AR 080701 DI 10.1103/PhysRevSTAB.6.080701 PG 12 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 721LV UT WOS:000185318600002 ER PT J AU Shepard, KW Ostroumov, PN Delayen, JR AF Shepard, KW Ostroumov, PN Delayen, JR TI High-energy ion linacs based on superconducting spoke cavities SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB The applicability of superconducting TEM-class spoke cavities to high-energy ion linacs is discussed, and detailed designs for two TEM-class, triple-spoke-loaded superconducting niobium resonant cavities are presented. The 345 MHz cavities have a velocity range of 0.4< beta < 0.75 and a beam aperture of 4 cm. Spoke-loaded cavities offer several advantages compared with the higher-frequency elliptical-cell cavities that are currently being developed for this range of particle velocities. The proposed triple-spoke cavities can provide broader velocity acceptance, more accelerating voltage per cavity, reduced heat-load operation at 4.2 K, and increased longitudinal acceptance through the high-energy section. Application to the proposed U. S. rare-isotope accelerator driver linac is discussed in detail. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Shepard, KW (reprint author), Argonne Natl Lab, Div Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 32 TC 25 Z9 26 U1 1 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD AUG PY 2003 VL 6 IS 8 AR 080101 DI 10.1103/PhysRevSTAB.6.080101 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 721LV UT WOS:000185318600001 ER PT J AU Startsev, EA Davidson, RC Qin, H AF Startsev, EA Davidson, RC Qin, H TI Analytical theory and nonlinear delta f perturbative simulations of temperature anisotropy instability in intense charged particle beams SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article ID STABILITY PROPERTIES; PRESSURE-ANISOTROPY; FOCUSING FIELD; SPACE-CHARGE; PROPAGATION AB In plasmas with strongly anisotropic distribution functions (T-parallel tob/T-perpendicular tob << 1) a Harris-like collective instability may develop if there is sufficient coupling between the transverse and longitudinal degrees of freedom. Such anisotropies develop naturally in accelerators and may lead to a deterioration of beam quality. This paper extends previous numerical studies [E. A. Startsev, R. C. Davidson, and H. Qin, Phys. Plasmas 9, 3138 ( 2002)] of the stability properties of intense non-neutral charged particle beams with large temperature anisotropy (T-perpendicular tob >> T-parallel tob) to allow for nonaxisymmetric perturbations with partial derivative/partial derivativetheta not equal 0. The most unstable modes are identified, and their eigenfrequencies, radial mode structure, and nonlinear dynamics are determined. The simulation results clearly show that moderately intense beams with s(b) = (omega) over cap (2)(pb)/2gamma(b)(2)omega(betaperpendicular to)(2) greater than or similar to 0.5 are linearly unstable to short-wavelength perturbations with k(z)(2) z(b)(2) greater than or similar to 1, provided the ratio of longitudinal and transverse temperatures is smaller than some threshold value. Here, (omega) over cap (2)(pb) = 4pi(n) over cap (b)e(b)(2)/gamma(b)m(b) is the relativistic plasma frequency squared, and omega(betaperpendicular to) is the betatron frequency associated with the applied smooth-focusing field. A theoretical model is developed based on the Vlasov-Maxwell equations which describes the essential features of the linear stages of instability. Both the simulations and the analytical theory predict that the dipole mode ( azimuthal mode number m = 1) is the most unstable mode. In the nonlinear stage, tails develop in the longitudinal momentum distribution function, and the kinetic instability saturates due to resonant wave-particle interactions. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Startsev, EA (reprint author), Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. NR 41 TC 37 Z9 39 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD AUG PY 2003 VL 6 IS 8 AR 084401 DI 10.1103/PhysRevSTAB.6.084401 PG 15 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 721LV UT WOS:000185318600007 ER PT J AU Archer, TD Birse, SEA Dove, MT Redfern, SAT Gale, JD Cygan, RT AF Archer, TD Birse, SEA Dove, MT Redfern, SAT Gale, JD Cygan, RT TI An interatomic potential model for carbonates allowing for polarization effects SO PHYSICS AND CHEMISTRY OF MINERALS LA English DT Article DE calcite; aragonite; empirical interatomic shell ID CRYSTAL-STRUCTURE; PHASE-TRANSITION; LATTICE-DYNAMICS; CALCITE; CACO3; ARAGONITE; DEPENDENCE; SIMULATION AB An empirical model for investigating the behaviour of CaCO3 polymorphs incorporating a shell model for oxygen has been created. The model was constructed by fitting to: the structure of aragonite and calcite; their elastic, static and high-frequency dielectric constants; phonon frequencies at the wave vectors [1/2 0 2] and [0 0 0] of calcite; and vibrational frequencies of the carbonate deformation modes of calcite. The high-pressure phase transition between calcite I and II is observed. The potentials for the CO3 group were transferred to other carbonates, by refitting the interaction between CO3 and the cation to both the experimental structures and their bulk modulus, creating a set of potentials for calculating the properties of a wide range of carbonate materials. Defect energies of substitutional cation defects were analyzed for calcite and aragonite phases. The results were rationalized by studying the structure of calcite and aragonite in greater detail. C1 Univ Cambridge, Dept Earth Sci, Cambridge CB2 3EQ, England. Univ London Imperial Coll Sci Technol & Med, Dept Chem, London SW7 2AY, England. Sandia Natl Labs, Dept Geochem, Albuquerque, NM 87185 USA. RP Redfern, SAT (reprint author), Univ Cambridge, Dept Earth Sci, Downing St, Cambridge CB2 3EQ, England. RI Dove, Martin/D-1517-2010; Redfern, Simon/B-3733-2010; Gale, Julian/B-7987-2009; OI Redfern, Simon/0000-0001-9513-0147; Gale, Julian/0000-0001-9587-9457; Archer, Thomas/0000-0003-4105-4980 NR 25 TC 37 Z9 37 U1 3 U2 22 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0342-1791 J9 PHYS CHEM MINER JI Phys. Chem. Miner. PD AUG PY 2003 VL 30 IS 7 BP 416 EP 424 DI 10.1007/s00269-002-0269-z PG 9 WC Materials Science, Multidisciplinary; Mineralogy SC Materials Science; Mineralogy GA 724JR UT WOS:000185484900004 ER PT J AU Withers, SH Peale, RE Schulte, AF Braunstein, G Beck, KM Hess, WP Reeder, RJ AF Withers, SH Peale, RE Schulte, AF Braunstein, G Beck, KM Hess, WP Reeder, RJ TI Broad distribution of crystal-field environments for Nd3+ in calcite SO PHYSICS AND CHEMISTRY OF MINERALS LA English DT Article DE calcium carbonate; calcite; neodymium; carbonate minerals; nuclear waste ID STRONTIUM FLUOROVANADATE; SPECTROSCOPY; LUMINESCENCE; 25-DEGREES-C; COORDINATION; ELEMENTS; SORPTION; XAFS AB Calcite crystals were grown from solution with single-crystal dimensions up to 3 mm and doped up to similar to0.1 at% with Nd3+ ions. Phase purity was verified by powder X-ray diffraction. The concentration of Nd3+ was measured by energy-dispersive spectrometry and Rutherford backscattering spectrometry. Micro X-ray fluorescence mapping of the calcite grains indicates uniform Nd distribution in as-grown crystal grains. X-ray absorption fine structure suggests that Nd3+ is substituted for Ca2+ with local lattice distortion. Temperature-dependent near-infrared spectroscopy of Nd3+ impurities in calcite reveals large inhomogeneous linewidths and smooth line profiles that are characteristic of glassy hosts, though the samples are well crystallized. C1 Univ Cent Florida, Dept Phys, Orlando, FL 32816 USA. Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA USA. SUNY Stony Brook, Ctr Environm Mol Sci, Dept Geosci, Stony Brook, NY 11794 USA. RP Peale, RE (reprint author), Univ Cent Florida, Dept Phys, Orlando, FL 32816 USA. NR 34 TC 12 Z9 12 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0342-1791 J9 PHYS CHEM MINER JI Phys. Chem. Miner. PD AUG PY 2003 VL 30 IS 7 BP 440 EP 448 DI 10.1007/s00269-003-0331-5 PG 9 WC Materials Science, Multidisciplinary; Mineralogy SC Materials Science; Mineralogy GA 724JR UT WOS:000185484900007 ER PT J AU Abarzhi, SI Glimm, J Lin, AD AF Abarzhi, SI Glimm, J Lin, AD TI Dynamics of two-dimensional Rayleigh-Taylor bubbles for fluids with a finite density contrast SO PHYSICS OF FLUIDS LA English DT Article ID INSTABILITY; SIMILARITY; MODEL; SCALE; FLOW; LAWS AB We study the motion of a two-dimensional coherent structure of bubbles and spikes in the Rayleigh-Taylor instability for fluids with a finite density contrast in the case of a small amplitude initial perturbation. The theoretical and numerical solutions for the system of conservation laws are found, and the dynamics of the bubble shape and velocity in the nonlinear regime is described. Good agreement between theory and simulations is achieved. A comparison to earlier models is performed. (C) 2003 American Institute of Physics. C1 Stanford Univ, Ctr Turbulence Res, Stanford, CA 94305 USA. SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Ctr Data Intens Comp, Upton, NY 11973 USA. Natl Chung Cheng Univ, Dept Math, Chiayi 621, Taiwan. RP Abarzhi, SI (reprint author), Stanford Univ, Ctr Turbulence Res, Stanford, CA 94305 USA. NR 24 TC 15 Z9 15 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD AUG PY 2003 VL 15 IS 8 BP 2190 EP 2197 DI 10.1063/1.1583732 PG 8 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 700GK UT WOS:000184104100012 ER PT J AU Debusschere, BJ Najm, HN Matta, A Knio, OM Ghanem, RG Le Maitre, OP AF Debusschere, BJ Najm, HN Matta, A Knio, OM Ghanem, RG Le Maitre, OP TI Protein labeling reactions in electrochemical microchannel flow: Numerical simulation and uncertainty propagation SO PHYSICS OF FLUIDS LA English DT Article ID CAPILLARY-ZONE-ELECTROPHORESIS; COMPUTER-SIMULATION; EXPERIMENTAL VALIDATION; ELECTROOSMOTIC FLOW; FLUID-FLOW; SEPARATIONS; BEHAVIOR; SYSTEMS AB This paper presents a model for two-dimensional electrochemical microchannel flow including the propagation of uncertainty from model parameters to the simulation results. For a detailed representation of electroosmotic and pressure-driven microchannel flow, the model considers the coupled momentum, species transport, and electrostatic field equations, including variable zeta potential. The chemistry model accounts for pH-dependent protein labeling reactions as well as detailed buffer electrochemistry in a mixed finite-rate/equilibrium formulation. Uncertainty from the model parameters and boundary conditions is propagated to the model predictions using a pseudo-spectral stochastic formulation with polynomial chaos (PC) representations for parameters and field quantities. Using a Galerkin approach, the governing equations are reformulated into equations for the coefficients in the PC expansion. The implementation of the physical model with the stochastic uncertainty propagation is applied to protein-labeling in a homogeneous buffer, as well as in two-dimensional electrochemical microchannel flow. The results for the two-dimensional channel show strong distortion of sample profiles due to ion movement and consequent buffer disturbances. The uncertainty in these results is dominated by the uncertainty in the applied voltage across the channel. (C) 2003 American Institute of Physics. C1 Sandia Natl Labs, Livermore, CA 94550 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Evry Val Essonne, Evry, France. RP Debusschere, BJ (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. RI Knio, Omar/A-3318-2010; Ghanem, Roger/B-8570-2008; Le Maitre, Olivier/D-8570-2011 OI Ghanem, Roger/0000-0002-1890-920X; Le Maitre, Olivier/0000-0002-3811-7787 NR 29 TC 50 Z9 50 U1 1 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 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD AUG PY 2003 VL 15 IS 8 BP 2238 EP 2250 DI 10.1063/1.1582857 PG 13 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 700GK UT WOS:000184104100017 ER PT J AU Clark, TT AF Clark, TT TI A numerical study of the statistics of a two-dimensional Rayleigh-Taylor mixing layer SO PHYSICS OF FLUIDS LA English DT Article ID INSTABILITY; SIMULATION; DEPENDENCE; MODEL; FLOW AB A two-dimensional Rayleigh-Taylor mixing layer was numerically simulated to determine the growth rate of the mixing layer for an ensemble of initial conditions. The numerical algorithm used is a recently developed lattice Boltzmann method for multiphase flow. Small variations in the initial conditions of the fluid interface are observed to yield large variations in the growth rate of the mixing-layer width. Consequently, an ensemble of simulations has been generated to provide a statistical basis for determining the mixing-layer growth rate. The results for this ensemble indicate that the mixing-layer attains an approximate state of self-similarity and yields a distribution of mixing-layer growth rates. (C) 2003 American Institute of Physics. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Clark, TT (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 23 TC 40 Z9 41 U1 0 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 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD AUG PY 2003 VL 15 IS 8 BP 2413 EP 2423 DI 10.1063/1.1589015 PG 11 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 700GK UT WOS:000184104100031 ER PT J AU Samtaney, R AF Samtaney, R TI Suppression of the Richtmyer-Meshkov instability in the presence of a magnetic field SO PHYSICS OF FLUIDS LA English DT Article AB We present numerical evidence from two dimensional simulations that the growth of the Richtmyer-Meshkov instability is suppressed in the presence of a magnetic field. A bifurcation occurs during the refraction of the incident shock on the density interface which transports baroclinically generated vorticity away from the interface to a pair of slow or intermediate magnetosonic shocks. Consequently, the density interface is devoid of vorticity and its growth and associated mixing is completely suppressed. (C) 2003 American Institute of Physics. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Samtaney, R (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 12 TC 35 Z9 35 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 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD AUG PY 2003 VL 15 IS 8 BP L53 EP L56 DI 10.1063/1.1591188 PG 4 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 700GK UT WOS:000184104100001 ER PT J AU Daughton, W AF Daughton, W TI Electromagnetic properties of the lower-hybrid drift instability in a thin current sheet SO PHYSICS OF PLASMAS LA English DT Article ID MAGNETIC NEUTRAL SHEET; ANOMALOUS RESISTIVITY; NONLINEAR EVOLUTION; TEARING INSTABILITY; KINK INSTABILITY; PLASMA SHEET; RECONNECTION; SIMULATIONS; DYNAMICS; MAGNETOTAIL AB The linear and nonlinear properties of the lower-hybrid drift instability are examined in a thin current sheet with thickness comparable to a thermal ion gyroradius rho(i) similar to L. The linear Vlasov stability is calculated using a formally exact technique in which the orbit integrals are treated numerically and the eigenvalue problem for the resulting system of integrodifferential equations is solved using a finite element representation of the eigenfunction. For the fastest growing lower-hybrid modes with wavelength on the electron gyroscale (k(y)rho(e) similar to 1), the resulting mode structure is localized on the edge of the current sheet. However, for modes with wavelengths intermediate between the electron and ion gyroscale k(y)root(ρ(i)ρ(e)) over bar similar to 1, the lower-hybrid instability has a significant electromagnetic component to the mode structure which is localized in the central region of the sheet. The addition of a weak guide field complicates the mode structure and gives rise to fluctuations in all three components of the magnetic field. These new predictions from linear Vlasov theory are confirmed using fully kinetic particle-in-cell simulations which indicate the modes saturate at large amplitude in the central region of the sheet. These results suggest the possibility that the electromagnetic fluctuations may potentially influence the development of magnetic reconnection. (C) 2003 American Institute of Physics. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Daughton, W (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Daughton, William/L-9661-2013 NR 43 TC 124 Z9 125 U1 1 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3103 EP 3119 DI 10.1063/1.1594724 PG 17 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800008 ER PT J AU Lukin, VS Jardin, SC AF Lukin, VS Jardin, SC TI Magnetohydrodynamic modeling of two-dimensional reconnection in the Magnetic Reconnection Experiment SO PHYSICS OF PLASMAS LA English DT Article ID SWARTHMORE SPHEROMAK EXPERIMENT; COLLISIONLESS RECONNECTION; ENERGETIC PARTICLES; SIMULATIONS; ALGORITHM; PLASMA AB A two-dimensional magnetohydrodynamics (MHD) code is used to investigate the dynamical evolution of driven reconnection in the Magnetic Reconnection Experiment (MRX) [M. Yamada et al., Phys. Plasmas 7, 1781 (2000)]. The initial conditions and dimensionless parameters of the simulation are set to be similar to the experimental values. Many features of the time-evolution of magnetic configurations for both co- and counter-helicity reconnection in MRX are successfully reproduced in the framework of resistive MHD. The resistive MHD model is then augmented by the addition of a "model Hall" term to begin to assess the importance of two-fluid physics in the experiment. The effective decoupling of the ion fluid from the reconnecting magnetic field due to the model Hall term is shown to be important during the early dynamic X-phase of MRX reconnection, while effectively negligible during the late "steady-state" Y-phase, when plasma heating takes place. These results are consistent with the available experimental evidence. Based on simple symmetry considerations, an experiment to directly measure the Hall effect in MRX configuration is proposed and numerical evidence for the expected outcome is given. (C) 2003 American Institute of Physics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Lukin, VS (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Jardin, Stephen/E-9392-2010 NR 32 TC 5 Z9 5 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3131 EP 3138 DI 10.1063/1.1591182 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800010 ER PT J AU Lee, WW Qin, H AF Lee, WW Qin, H TI Alfven waves in gyrokinetic plasmas SO PHYSICS OF PLASMAS LA English DT Article ID PARTICLE SIMULATION; TURBULENT TRANSPORT; EQUATIONS; DYNAMICS; TOKAMAKS; MODEL; DRIFT AB A brief comparison of the properties of Alfven waves that are based on the gyrokinetic description with those derived from the magnetohydrodynamics (MHD) equations is presented. The critical differences between these two approaches are the treatment of the ion polarization effects. As such, the compressional Alfven waves in a gyrokinetic plasma can be eliminated through frequency ordering, whereas geometric simplifications are needed to decouple the shear Alfven waves from the compressional Alfven waves within the context of MHD. Theoretical and numerical procedures of using gyrokinetic particle simulation for studying microturbulence and kinetic-MHD physics including finite Larmor radius effects are also presented. (C) 2003 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Lee, WW (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 23 TC 17 Z9 17 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3196 EP 3203 DI 10.1063/1.1590666 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800018 ER PT J AU Lewandowski, JLV AF Lewandowski, JLV TI Multigrid particle-in-cell simulations of plasma microturbulence SO PHYSICS OF PLASMAS LA English DT Article ID ITERATIVE SOLUTION; TRANSPORT; ALGORITHM; EQUATIONS; GEOMETRY AB A new scheme to accurately retain kinetic electron effects in particle-in-cell (PIC) simulations for the case of electrostatic drift waves is presented. The splitting scheme, which is based on exact separation between adiabatic and nonadiabatic electron responses, is shown to yield more accurate linear growth rates than the standard deltaf scheme. The linear and nonlinear elliptic problems that arise in the splitting scheme are solved using a multigrid solver. The multigrid PIC approach offers an attractive path, both from the physics and numerical points of view, to simulate kinetic electron dynamics in global toroidal plasmas. (C) 2003 American Institute of Physics. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Lewandowski, JLV (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 13 TC 13 Z9 13 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3204 EP 3211 DI 10.1063/1.1591186 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800019 ER PT J AU Spong, DA Sanchez, R Weller, A AF Spong, DA Sanchez, R Weller, A TI Shear Alfven continua in stellarators SO PHYSICS OF PLASMAS LA English DT Article ID LOW-PRESSURE PLASMAS; IDEAL MAGNETOHYDRODYNAMICS; OPTIMIZED STELLARATORS; MODE RESONANCES; PHYSICS ISSUES; EIGENMODES; CONFIGURATIONS; INSTABILITIES; EXCITATION; EQUILIBRIA AB Shear Alfven continua have been calculated for stellarators over a range of shapes and aspect ratios as a first step toward understanding Alfven instability induced fast ion losses in such systems and possible means for minimizing these losses. Stellarators introduce strong poloidal/toroidal couplings in both \B\ and the g(pp) metric coefficient that can induce new continuum gap structures not present in axisymmetric tokamaks. Low field period (N-fp = 2 - 3), low aspect ratio devices result in strongly coupled toroidal mode families (n = +/- n(o), +/-n(o)+/-N-fp,+/-n(o) +/-2N(fp), etc.) that lead to helically coupled Alfven gaps at lower frequencies and with wider gap structures than are the case for larger aspect ratio, higher field period stellarator devices. (C) 2003 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Carlos III Madrid, Madrid, Spain. IPP Euratom, Max Planck Inst Plasmaphys, Garching, Germany. RP Spong, DA (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. RI Sanchez, Raul/C-2328-2008; Spong, Donald/C-6887-2012 OI Spong, Donald/0000-0003-2370-1873 NR 29 TC 25 Z9 25 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3217 EP 3224 DI 10.1063/1.1590316 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800021 ER PT J AU Belova, EV Gorelenkov, NN Cheng, CZ AF Belova, EV Gorelenkov, NN Cheng, CZ TI Self-consistent equilibrium model of low aspect-ratio toroidal plasma with energetic beam ions SO PHYSICS OF PLASMAS LA English DT Article ID GUIDING CENTER MOTION; PARTICLE ORBITS; PHYSICS; SYSTEMS AB A theoretical model is developed which allows the self-consistent inclusion of the effects of energetic beam ions in equilibrium calculations of low-aspect-ratio toroidal devices. A two-component plasma is considered, where the energetic ions are treated using a kinetic Vlasov description, while a one-fluid magnetohydrodynamic description is used to represent the thermal plasma. The model allows for an amsotropic distribution function and a large Larmor radius of the beam ions. Numerical results are obtained for neutral-beam-heated plasmas in the National Spherical Torus Experiment (NSTX) [M. Ono, S. M. Kaye, Y.-K. M. Peng et al., Nucl. Fusion 40, 557 (2000)]. Self-consistent equilibria with an anisotropic fast ion distribution have been calculated for NSTX. It is shown for typical experimental parameters that the contribution of the energetic neutral beam ions to the total current can be comparable to that of the background plasma, and that the kinetic modifications of the equilibrium can be significant. The range of validity of the finite-Larmor-radius expansion and of the reduced kinetic descriptions for the beam ions in NSTX is discussed. The calculated kinetic equilibria can be used for self-consistent numerical studies of beam-ion-driven instabilities in NSTX. (C) 2003 American Institute of Physics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Belova, EV (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Cheng, Chio/K-1005-2014 NR 21 TC 20 Z9 20 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3240 EP 3251 DI 10.1063/1.1592155 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800023 ER PT J AU Sanford, TWL Lemke, RW Mock, RC Peterson, DL AF Sanford, TWL Lemke, RW Mock, RC Peterson, DL TI Trends in radiation production from dynamic-hohlraums driven by single and nested wire arrays SO PHYSICS OF PLASMAS LA English DT Article ID Z-PINCH EXPERIMENTS; X-RAY POWER; 2-DIMENSIONAL SIMULATIONS; RELEVANT HOHLRAUMS; IMPLOSION PHASE; MAGNETIC-FLUX; Z-ACCELERATOR; NUMBER; PLASMA; INSTABILITIES AB The axial radiation developed primarily from the interior of an imploding dynamic hohlraum (DH) target within a Z pinch using a single array with a large number of tungsten wires is compared with that generated using a standard [Phys. Plasmas 9, 3573 (2002)] nested (outer plus inner) array on Z. Measurements indicate that a single-array with a mass (2.5 mg) near that of the combined mass of the nested-array maximizes the DH axial power. At this mass, the DH utilizing the standard nested array generates (23 +/- 15) % more axial power than that of a single array. Measurements over a range of single-array masses (2-6 mg) show a decrease in radiation power for masses above 3.5 mg. Two-dimensional radiation magnetohydrodynamic simulations, which have successfully described radial emission from targetless implosions for both single and nested-array configurations [Phys. Plasmas 6, 2178 (1999)], however, do not follow the observed trends well. This lack of tracking implies that current 2D models, which take into account the development of the magnetic Rayleigh-Taylor (RT) instability in the r-z plane, require improvements in order to provide a self-consistent description of the implosion dynamics and radiation production for DH experiments. (C) 2003 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sanford, TWL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM twsanfo@sandia.gov NR 59 TC 17 Z9 17 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3252 EP 3264 DI 10.1063/1.1587708 PG 13 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800024 ER PT J AU Allen, M Sentoku, Y Audebert, P Blazevic, A Cowan, T Fuchs, J Gauthier, JC Geissel, M Hegelich, M Karsch, S Morse, E Patel, PK Roth, M AF Allen, M Sentoku, Y Audebert, P Blazevic, A Cowan, T Fuchs, J Gauthier, JC Geissel, M Hegelich, M Karsch, S Morse, E Patel, PK Roth, M TI Proton spectra from ultraintense laser-plasma interaction with thin foils: Experiments, theory, and simulation SO PHYSICS OF PLASMAS LA English DT Article ID SOLID INTERACTIONS; ION; GENERATION; ACCELERATION; ELECTRON; PULSES; BEAMS AB A beam of high energy ions and protons is observed from targets irradiated with intensities up to 5 X 10(19) W/cm(2). Maximum proton energy is shown to strongly correlate with laser-irradiance on target. Energy spectra from a magnetic spectrometer show a plateau region near the maximum energy cutoff and modulations in the spectrum at approximately 65% of the cutoff energy. Presented two-dimensional particle-in-cell simulations suggest that modulations in the proton spectrum are caused by the presence of multiple heavy-ion species in the expanding plasma. (C) 2003 American Institute of Physics. C1 Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. Gen Atom Co, San Diego, CA 92186 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Ecole Polytech, Lab Utilisat Lasers Intenses, F-91128 Palaiseau, France. Tech Univ Darmstadt, D-64289 Darmstadt, Germany. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. RP Allen, M (reprint author), Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. RI Patel, Pravesh/E-1400-2011; Fuchs, Julien/D-3450-2016; Cowan, Thomas/A-8713-2011; Sentoku, Yasuhiko/P-5419-2014 OI Fuchs, Julien/0000-0001-9765-0787; Cowan, Thomas/0000-0002-5845-000X; NR 19 TC 92 Z9 93 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3283 EP 3289 DI 10.1063/1.1592154 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800027 ER PT J AU Davis, HA Olson, RT Moir, DC AF Davis, HA Olson, RT Moir, DC TI Neutral desorption from intense electron beam impact on solid surfaces SO PHYSICS OF PLASMAS LA English DT Article ID IONIZATION CROSS-SECTIONS; TARGET AB Neutrals desorbed from solid surfaces by electron beam impact can be ionized by the beam and trapped in the beam potential causing beam disruption. This can increase the beam diameter on radiographic bremsstrahlung targets degrading resolution. Measurements of the number and species of neutrals desorbed by impact of a 19.8 MeV, 1.7 kA, 60 ns electron beam on thin-foil targets are made in open and closed geometries. The study focuses on aluminum and graphite foil surfaces. A fast Bayard-Alpert ionization gauge measures the number of neutral molecules released, and a quadrupole mass spectrometer measures the species mix. At high beam current density, where thermal desorption due to target heating is expected, the dominant neutral species is H2O, and approximately one monolayer of desorbed gas is released. Other prominent species such as H-2, CO, and CO2 are not thermally desorbed until current densities near foil destruction are approached. The observations are in agreement with a previous hypothesis based on the comparison of computer calculations with beam-dynamics observations. (C) 2003 American Institute of Physics. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM davis@lanl.gov NR 19 TC 3 Z9 3 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3351 EP 3357 DI 10.1063/1.1592802 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800035 ER PT J AU Clark, DS Fisch, NJ AF Clark, DS Fisch, NJ TI Operating regime for a backward Raman laser amplifier in preformed plasma SO PHYSICS OF PLASMAS LA English DT Article ID STIMULATED RAMAN; PARAMETRIC-INSTABILITIES; BRILLOUIN-SCATTERING; EVOLUTION; BEHAVIOR; PULSES; DRIVEN; SPACE; BEAMS AB A critical issue in the generation of ultraintense, ultrashort laser pulses by backward Raman scattering in plasma is the stability of the pumping pulse to premature backscatter from thermal fluctuations in the preformed plasma. Malkin et al. [Phys. Rev. Lett. 84, 1208 (2000)] demonstrated that density gradients may be used to detune the Raman resonance in such a way that backscatter of the pump from thermal noise can be stabilized while useful Raman amplification persists. Here plasma conditions for which the pump is stable to thermal Raman backscatter in a homogeneous plasma and the density gradients necessary to stabilize the pump for other plasma conditions are quantified. Other ancillary constraints on a Raman amplifier are also considered to determine a specific region in the T-e-n(e) plane where Raman amplification is feasible. By determining an operability region, the degree of uncertainty in density or temperature tolerable for an experimental Raman amplifier is thus also identified. The fluid code FD [R. L. Berger et al., Phys. Plasmas 5, 4337 (1998)], which includes the effects of thermal fluctuations, is used to verify these analytic estimates. (C) 2003 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Clark, DS (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 22 TC 47 Z9 47 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3363 EP 3370 DI 10.1063/1.1590667 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800037 ER PT J AU Geddes, CGR Kirkwood, RK Glenzer, SH Estabrook, K Cohen, BI Young, PE Joshi, C Wharton, KB AF Geddes, CGR Kirkwood, RK Glenzer, SH Estabrook, K Cohen, BI Young, PE Joshi, C Wharton, KB TI Observation of ion wave decay products of Langmuir waves generated by stimulated Raman scattering in ignition scale plasmas SO PHYSICS OF PLASMAS LA English DT Article ID LASER-PLASMA; PARAMETRIC-INSTABILITIES; NONLINEAR SATURATION; HOHLRAUM PLASMAS; ACOUSTIC-WAVES; ENHANCEMENT; BRILLOUIN; DRIVEN AB Thomson scattering has been used to measure the time resolved spectrum of ion wave decay products from two instabilities which can limit the growth of stimulated Raman scattering (SRS). This experiment detected ion wave decay products far above the thermal level and demonstrates that SRS produced Langmuir waves undergo the Langmuir decay instability in ignition relevant plasmas. Product waves of the electromagnetic decay instability were not detected. (C) 2003 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. San Jose State Univ, San Jose, CA 95192 USA. RP Geddes, CGR (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 29 TC 9 Z9 10 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD AUG PY 2003 VL 10 IS 8 BP 3422 EP 3425 DI 10.1063/1.1590317 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 707CL UT WOS:000184491800045 ER PT J AU Torres, DF Romero, GE Dame, TM Combi, JA Butt, YM AF Torres, DF Romero, GE Dame, TM Combi, JA Butt, YM TI Supernova remnants and gamma-ray sources SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review DE gamma-rays; observations; gamma-rays; theory; ISM; supernova remnants; ISM; clouds; cosmic rays ID UNIDENTIFIED EGRET SOURCES; GALACTIC PLANE SURVEY; HIGH-ENERGY EMISSION; ACCELERATED COSMIC-RAYS; RADIO-CONTINUUM SURVEY; PULSAR SAX J0635+0533; ACCRETING BLACK-HOLE; AIR-SHOWER ARRAY; EARLY-TYPE STARS; X-RAY AB A review of the possible relationship between x-ray sources and supernova remnants (SNRs) is presented. Particular emphasis is given to the analysis of the observational status of the problem of cosmic ray acceleration at SNR shock fronts. All positional coincidences between SNRs and unidentified gamma-ray sources listed in the Third EGRET Catalog at low Galactic latitudes are discussed on a case by case basis. For several coincidences of particular interest, new CO(J = 1 - 0) and radio continuum maps are shown, and the mass content of the SNR surroundings is determined. The contribution to the T-ray flux observed that might come from cosmic ray particles (particularly nuclei) locally accelerated at the SNR shock fronts is evaluated. We discuss the prospects for future research in this field and remark on the possibilities for observations with forthcoming gamma-ray instruments. (C) 2003 Published by Elsevier B.V. C1 Lawrence Livermore Lab, Livermore, CA 94550 USA. Inst Argentino Radioastron, Buenos Aires, DF, Argentina. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Lawrence Livermore Lab, 7000 E Ave,L-413, Livermore, CA 94550 USA. EM dtorres@igpp.uclln1.org RI Torres, Diego/O-9422-2016 OI Torres, Diego/0000-0002-1522-9065 NR 293 TC 104 Z9 104 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 EI 1873-6270 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD AUG PY 2003 VL 382 IS 6 BP 303 EP 380 DI 10.1016/S0370-1573(03)00201-1 PG 78 WC Physics, Multidisciplinary SC Physics GA 703RG UT WOS:000184294300001 ER PT J AU Carey, DC AF Carey, DC TI Karl Brown's role in TRANSPORT SO PHYSICS TODAY LA English DT Letter C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Carey, DC (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 0 TC 0 Z9 0 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 0031-9228 J9 PHYS TODAY JI Phys. Today PD AUG PY 2003 VL 56 IS 8 BP 14 EP 14 DI 10.1063/1.1611339 PG 1 WC Physics, Multidisciplinary SC Physics GA 706LD UT WOS:000184454400009 ER PT J AU Crease, RP AF Crease, RP TI IBM gears up to gene challenge SO PHYSICS WORLD LA English DT Editorial Material C1 SUNY Stony Brook, Dept Philosophy, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Crease, RP (reprint author), SUNY Stony Brook, Dept Philosophy, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD AUG PY 2003 VL 16 IS 8 BP 14 EP 14 PG 1 WC Physics, Multidisciplinary SC Physics GA 713LK UT WOS:000184859300017 ER PT J AU Suttrop, W Maraschek, M Conway, GD Fahrbach, HU Haas, G Horton, LD Kurki-Suonio, T Lasnier, CJ Leonard, AW Maggi, CF Meister, H Muck, A Neu, R Nunes, I Putterich, T Reich, M Sips, ACC AF Suttrop, W Maraschek, M Conway, GD Fahrbach, HU Haas, G Horton, LD Kurki-Suonio, T Lasnier, CJ Leonard, AW Maggi, CF Meister, H Muck, A Neu, R Nunes, I Putterich, T Reich, M Sips, ACC CA ASDEX Upgrade Team TI ELM-free stationary H-mode plasmas in the ASDEX upgrade tokamak SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID DIII-D TOKAMAK; DOUBLE-BARRIER REGIME; CONFINEMENT; DISCHARGES; BEHAVIOR; PARTICLE AB ELM-free H-mode plasmas with stationary plasma density and radiation level are obtained in the ASDEX Upgrade tokamak with large clearance between the last closed flux surface and the wall, and neutral beam injection in a toroidal direction opposite to that of the plasma current. This behaviour is accompanied by a characteristic narrow-band magnetohydrodynamic (MHD) oscillation with clear harmonics up to n = 11 visible. This mode is localized in the plasma edge region. Conditions and properties of the stationary ELM-free phases and the edge MHD oscillation closely resemble that of the 'quiescent H-mode' and the 'edge harmonic oscillation' found in the DIII-D tokamak (Burrell K H et al 2002 Plasma Phys. Control. Fusion 44 A253). In addition, high-frequency MHD oscillations are found with an amplitude correlated with fluctuations of the divertor D-alpha intensity, suggesting a possible relevance of these modes for particle transport. C1 EURATOM, Max Planck Inst Plasmaphys, D-85740 Garching, Germany. Helsinki Univ Technol, Euratom TEKES Assoc, FIN-02015 Helsinki, Finland. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Gen Atom Co, San Diego, CA 92186 USA. Inst Super Tecn, Assoc EURATOM IST, Ctr Fusao Nucl, P-1049001 Lisbon, Portugal. RP Suttrop, W (reprint author), EURATOM, Max Planck Inst Plasmaphys, D-85740 Garching, Germany. RI Putterich, Thomas/A-6962-2012; Nunes, Isabel/D-1627-2017; Neu, Rudolf /B-4438-2010; OI Putterich, Thomas/0000-0002-8487-4973; Neu, Rudolf /0000-0002-6062-1955; Nunes, Isabel/0000-0003-0542-1982 NR 18 TC 49 Z9 49 U1 3 U2 18 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD AUG PY 2003 VL 45 IS 8 BP 1399 EP 1416 AR PII S0741-3335(03)62455-3 DI 10.1088/0741-3335/45/8/302 PG 18 WC Physics, Fluids & Plasmas SC Physics GA 717PB UT WOS:000185097600003 ER PT J AU Ramamurthi, B Economou, DJ Kaganovich, ID AF Ramamurthi, B Economou, DJ Kaganovich, ID TI Effect of electron energy distribution function on power deposition and plasma density in an inductively coupled discharge at very low pressures SO PLASMA SOURCES SCIENCE & TECHNOLOGY LA English DT Article ID RADIOFREQUENCY PLASMAS; ELECTROMAGNETIC WAVE; GLOW-DISCHARGES; ABSORPTION; SIMULATION; RESONANCE; EQUATION AB A self-consistent one-dimensional model was developed to study the effect of the electron energy distribution function (EEDF) on power deposition and plasma density profiles in a planar inductively coupled plasma (ICP) in the non-local regime (pressure less than or equal to10 mTorr). The model consisted of three modules: (1) an EEDF module to compute the non-Maxwellian EEDF, (2) a non-local electron kinetics module to predict the non-local electron conductivity, radio frequency (RF) current, electric field and power deposition profiles in the non-uniform plasma, and (3) a heavy species transport module to solve for the ion density and velocity profiles as well as the metastable density. Results using the non-Maxwellian EEDF model were compared with predictions using a Maxwellian EEDF, under otherwise identical conditions. The RF electric field, current and power deposition profiles were different, especially at 1 mTorr, for which the electron effective mean-free-path was larger than the skin depth. The plasma density predicted by the Maxwellian EEDF was up to 93% larger for the conditions examined. Thus, the non-Maxwellian EEDF must be accounted for in modelling ICPs at very low pressures. C1 Univ Houston, Dept Chem Engn, Plasma Proc Lab, Houston, TX 77204 USA. Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Ramamurthi, B (reprint author), Univ Houston, Dept Chem Engn, Plasma Proc Lab, Houston, TX 77204 USA. NR 40 TC 15 Z9 15 U1 0 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0963-0252 J9 PLASMA SOURCES SCI T JI Plasma Sources Sci. Technol. PD AUG PY 2003 VL 12 IS 3 BP 302 EP 312 AR PII S0963-0252(03)62087-6 DI 10.1088/0963-0252/12/3/302 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 720XX UT WOS:000185288900002 ER PT J AU Tuszewski, M White, RR Wurden, GA AF Tuszewski, M White, RR Wurden, GA TI Relaxation oscillations of low-frequency Ar/SF6 inductive plasma discharges SO PLASMA SOURCES SCIENCE & TECHNOLOGY LA English DT Article ID INSTABILITIES; MODELS AB A new class of relaxation oscillations has been observed in some inductive plasma discharges operated with low-pressure argon and SF6 gas mixtures. Some plasma instability seems to develop periodically in the downstream plasma. The nonlinear evolution and the two-dimensional spatial structure of the instabilities are detailed with Langmuir probe arrays and fast video imaging. The measurements show that the instabilities grow in a quasi-spherical downstream layer. The upstream plasma is slightly compressed, while large rarefactions are observed downstream. The upstream plasma then moves slowly downward until the initial plasma profiles are recovered. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Tuszewski, M (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Wurden, Glen/A-1921-2017 OI Wurden, Glen/0000-0003-2991-1484 NR 13 TC 16 Z9 17 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0963-0252 J9 PLASMA SOURCES SCI T JI Plasma Sources Sci. Technol. PD AUG PY 2003 VL 12 IS 3 BP 396 EP 402 AR PII S0963-0252(03)62503-X DI 10.1088/0963-0252/12/3/313 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 720XX UT WOS:000185288900013 ER PT J AU Green, MA Emery, K King, DL Igari, S Warta, W AF Green, MA Emery, K King, DL Igari, S Warta, W TI Solar cell efficiency tables (Version 22) SO PROGRESS IN PHOTOVOLTAICS LA English DT Article AB Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since January 2003 are reviewed. Copyright (C) 2003 John Wiley Sons, Ltd. C1 Univ New S Wales, Ctr Photovolta Engn, Sydney, NSW 2052, Australia. Natl Renewable Energy Lab, Golden, CO 80401 USA. Sandia Natl Labs, Albuquerque, NM 87123 USA. Natl Inst Adv Ind Sci & Technol, Energy Elect Inst, Tsukuba, Ibaraki, Japan. Fraunhofer Inst Solar Energy Syst, Dept Solar Cells Mat & Technol, D-79110 Freiburg, Germany. RP Green, MA (reprint author), Univ New S Wales, Ctr Photovolta Engn, Sydney, NSW 2052, Australia. EM m.green@unsw.edu.au NR 42 TC 67 Z9 72 U1 2 U2 15 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD AUG PY 2003 VL 11 IS 5 BP 347 EP 352 DI 10.1002/pip.499 PG 6 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 703TL UT WOS:000184297000006 ER PT J AU Tarver, CM Tran, TD Whipple, RE AF Tarver, CM Tran, TD Whipple, RE TI Thermal decomposition of pentaerythritol tetranitrate SO PROPELLANTS EXPLOSIVES PYROTECHNICS LA English DT Article DE pentaerythritol tetranitrate (PETN); thermal decomposition ID SOLID EXPLOSIVES AB A chemical kinetic model for the thermal decomposition of the solid high explosive pentaerythritol tetranitrate (PETN) is developed for prediction of times to thermal explosion using the Chemical TOPAZ heat transfer computer code. The model is based on times to thermal explosion measured in a new One Dimensional Time to Explosion (ODTX) apparatus. ODTX experiments are reported for pure PETN and for Semtex 1A. The pure PETN results are accurately modeled using a four reaction decomposition process in which an autocatalytic process produces intermediate reaction product gases, which subsequently react in a second order gas phase process to produce the final reaction products. Semtex 1A exhibits longer times to explosion than PETN at low temperatures, indicating that its endothermic binder decomposition absorbs heat produced by PETN decomposition. This binder reaction is modeled as a first order endothermic process. Three experiments on 5.08 cm diameter unconfined cylinders of PETN ramp heated to explosion at different rates are reported. The PETN model accurately predicts the thermocouple records and explosion times for these unconfined experiments in which only intermediate gaseous products can form. C1 Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. RP Tarver, CM (reprint author), Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. NR 14 TC 17 Z9 17 U1 1 U2 7 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0721-3115 J9 PROPELL EXPLOS PYROT JI Propellants Explos. Pyrotech. PD AUG PY 2003 VL 28 IS 4 BP 189 EP 193 DI 10.1002/prep.200300004 PG 5 WC Chemistry, Applied; Engineering, Chemical SC Chemistry; Engineering GA 717QP UT WOS:000185101100004 ER PT J AU Hoffman, DM AF Hoffman, DM TI Voids and density distributions in 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) prepared under various conditions SO PROPELLANTS EXPLOSIVES PYROTECHNICS LA English DT Article DE CL-20; voids; density; optical microscopy ID EXPLOSIVES; CRYSTALS AB The density distributions of six samples of CL-20 were measured using the density gradient technique. This technique was used to determine which preparation procedure produced the highest average CL-20 density. Assuming crystals with fewer flaws result in reduced sensitivity to shock initiation, higher average crystal density (closest to the theoretical maximum density) would imply the least number of voids or inclusions. Based on hot-spot theory, better crystals, i.e., smaller number of flaws will reduce the shock sensitivity and perhaps other impact initiation mechanisms as well. Six samples from different synthesis and crystallization procedures gave average densities from 2.042 to 2.0230 g/cm(3) as measured by density gradient. Assuming the voids have no density, the crystals were between 99.90 to 98.98% of the theoretical maximum density (TMD for epsilon-CL-20 is 2.044 g/cm(3)). An attempt was made to account for the density difference by identifying voids in the crystals using polarized light microscopy. This method also gave some insight into the different morphologies produced by different crystallization techniques. In 3 cases voids on the order of several micrometers could be resolved in large CL-20 crystals. C1 Lawrence Livermore Natl Lab, Energet Mat Ctr, Livermore, CA 94551 USA. RP Hoffman, DM (reprint author), Lawrence Livermore Natl Lab, Energet Mat Ctr, Livermore, CA 94551 USA. NR 16 TC 25 Z9 30 U1 1 U2 6 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0721-3115 J9 PROPELL EXPLOS PYROT JI Propellants Explos. Pyrotech. PD AUG PY 2003 VL 28 IS 4 BP 194 EP 200 DI 10.1002/prep.200300005 PG 7 WC Chemistry, Applied; Engineering, Chemical SC Chemistry; Engineering GA 717QP UT WOS:000185101100005 ER PT J AU Faulon, JL Sale, K Young, M AF Faulon, JL Sale, K Young, M TI Exploring the conformational space of membrane protein folds matching distance constraints SO PROTEIN SCIENCE LA English DT Article DE protein folds; helix packing; transmembrane helices; distance constraints ID BOVINE RHODOPSIN; CROSS-LINKS; SPIN LABELS; PREDICTION; ACTIVATION; TOPOLOGY; HELICES; ENERGY; SITES; CHAIN AB Herein we present a computational technique for generating helix-membrane protein folds matching a predefined set of distance constraints, such as those obtained from NMR NOE, chemical cross-linking, dipolar EPR, and FRET experiments. The purpose of the technique is to provide initial structures for local conformational searches based on either energetic considerations or ad-hoc scoring criteria. In order to properly screen the conformational space, the technique generates an exhaustive list of conformations within a specified root-mean-square deviation (RMSD) where the helices are positioned in order to match the provided distances. Our results indicate that the number of structures decreases exponentially as the number of distances increases, and increases exponentially as the errors associated with the distances increases. We also found the number of solutions to be smaller when all the distances share one helix in common, compared to the case where the distances connect helices in a daisy-chain manner. We found that for 7 helices, at least 15 distances with errors up to 8 Angstrom are needed to produce a number of solutions that is not too large to be processed by local search refinement procedures. Finally, without energetic considerations, our enumeration technique retrieved the transmembrane domains of Bacteriorhodopsin (PDB entry1c3w), Halorhodopsin (1e12), Rhodopsin (1f88), Aquaporin-1 (1fqy), Glycerol uptake facilitator protein (1fx8), Sensory Rhodopsin (1jgj), and a subunit of Fumarate reductase flavoprotein (1q1aC) with Calpha level RMSDs of 3.0 Angstrom, 2.3 Angstrom, 3.2 Angstrom, 4.6 Angstrom, 6.0 Angstrom, 3.7 Angstrom, and 4.4 Angstrom, respectively. C1 Sandia Natl Labs, Computat Biol Dept, Livermore, CA 94551 USA. RP Faulon, JL (reprint author), Sandia Natl Labs, Computat Biol Dept, POB 969,MS 9951, Livermore, CA 94551 USA. NR 26 TC 20 Z9 20 U1 0 U2 4 PU COLD SPRING HARBOR LAB PRESS, PUBLICATIONS DEPT PI WOODBURY PA 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2924 USA SN 0961-8368 J9 PROTEIN SCI JI Protein Sci. PD AUG PY 2003 VL 12 IS 8 BP 1750 EP 1761 DI 10.1110/ps.0305003 PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 705PH UT WOS:000184403100017 PM 12876324 ER PT J AU Kumaran, D Eswaramoorthy, S Gerchman, SE Kycia, H Studier, FW Swaminathan, S AF Kumaran, D Eswaramoorthy, S Gerchman, SE Kycia, H Studier, FW Swaminathan, S TI Crystal structure of a putative CN hydrolase from yeast SO PROTEINS-STRUCTURE FUNCTION AND GENETICS LA English DT Article DE structural genomics; hypothetical protein; CN-hydrolase/nitrilase; four-layer sandwich; X-ray diffraction; dimer ID MULTIPLE ISOMORPHOUS REPLACEMENT; AMINO-ACID AMIDOHYDROLASE; SITE-DIRECTED MUTAGENESIS; DIFFRACTION DATA; PROTEIN FAMILIES; BETA-LACTAMASE; DATABASE; NITRILASE; REVEALS; ENZYME AB The crystal structure of a yeast hypothetical protein with sequence similarity to CN hydrolases has been determined to 2.4 Angstrom resolution by the multiwavelength anomalous dispersion (MAD) method. The protein folds as a four-layer alphabetabetaalpha sandwich and exists as a dimer in the crystal and in solution. It was selected in a structural genomics project as representative of CN hydrolases at a time when no structures had been determined for members of this family. Structures for two other members of the family have since been reported and the three proteins have similar topology and dimerization modes, which are distinct from those of other alphabetabetaalpha proteins whose structures are known. The dimers form an unusual eight-layer alphabetabetaalpha:alphabetabetaalpha structure. Although the precise enzymatic reactions catalyzed by the yeast protein are not known, considerable information about the active site may be deduced from conserved sequence motifs, comparative biochemical information, and comparison with known structures of hydrolase active sites. As with serine hydrolases, the active-site nucleophile (cysteine in this case) is positioned on a nucleophile elbow. (C) 2003 Wiley-Liss, Inc. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Swaminathan, S (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. FU NIGMS NIH HHS [GM62529] NR 45 TC 41 Z9 43 U1 0 U2 4 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-3585 J9 PROTEINS JI Proteins PD AUG 1 PY 2003 VL 52 IS 2 BP 283 EP 291 DI 10.1002/prot.10417 PG 9 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 697BW UT WOS:000183923200016 PM 12833551 ER PT J AU Chen, WNU Yu, LR Strittmatter, EF Thrall, BD Camp, DG Smith, RD AF Chen, WNU Yu, LR Strittmatter, EF Thrall, BD Camp, DG Smith, RD TI Detection of in situ labeled cell surface proteins by mass spectrometry: Application to the membrane subproteome of human mammary epithelial cells SO PROTEOMICS LA English DT Article DE biotinylation; in situ labeling; liquid chromatography-tandem mass spectrometry membrane subproteome; tryptic digest ID IDENTIFICATION; BIOTINYLATION; PROTEOME AB Characterization of the surface exposed membrane subproteome of human mammary epithelial cells (strain 184 A1L5) implemented lysine specific in situ labeling of the proteins using sulfosuccinimidyl-6-(biotinamido)hexanoate, followed by enrichment of the biotinylated, tryptically digested peptides, and then liquid chromatography-tandem mass spectrometry analysis of the labeled peptides. Probing the membrane subproteome in this manner yielded unambiguous identification of proteins situated on the cell surface. The method reported can be adapted to include stable isotope labeling of proteins for quantitation of changes occurring on the cell surface in response to specific perturbations. 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, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 FU NCI NIH HHS [CA 93306] NR 8 TC 17 Z9 21 U1 2 U2 3 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 1615-9853 J9 PROTEOMICS JI Proteomics PD AUG PY 2003 VL 3 IS 8 BP 1647 EP 1651 DI 10.1002/pmic.200300468 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 716LZ UT WOS:000185031500028 PM 12923789 ER PT J AU Zhang, JJ Walter, WR Lay, T Wu, RS AF Zhang, JJ Walter, WR Lay, T Wu, RS TI Time-domain pure-state polarization analysis of surface waves traversing California SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE seismic wave polarization; surface waves; refraction ID ANZA SEISMIC NETWORK; UPPER-MANTLE; QUANTITATIVE MEASUREMENTS; EARTHQUAKE PREDICTION; SOUTHERN CALIFORNIA; PARTICLE MOTION; AZIMUTHAL ANISOTROPY; PHASE-VELOCITY; PROPAGATION; SPECTRA AB A time-domain pure-state polarization analysis method is used to characterize surface waves traversing California parallel to the plate boundary. The method is applied to data recorded at four broadband stations in California from twenty-six large, shallow earthquakes which occurred since 1988, yielding polarization parameters such as the ellipticity, Euler angles, instantaneous periods, and wave incident azimuths. The earthquakes are located along the circum-Pacific margin and the ray paths cluster into two groups, with great-circle paths connecting stations MHC and PAS or CMB and GSC. The first path (MHC-PAS) is in the vicinity of the San Andreas Fault System (SAFS), and the second (CMB-GSC) traverses the Sierra Nevada Batholith parallel to and east of the SAFS. Both Rayleigh and Love wave data show refractions due to lateral velocity heterogeneities under the path, indicating that accurate phase velocity and attenuation analysis requires array measurements. The Rayleigh waves are strongly affected by low velocity anomalies beneath Central California, with ray paths bending eastward as waves travel toward the south, while Love waves are less affected, providing observables to constrain the depth extent of anomalies. Strong lateral gradients in the lithospheric structure between the continent and the ocean are the likely cause of the path deflections. C1 Univ Calif Santa Cruz, Inst Geophys & Planetary Sci, Santa Cruz, CA 95064 USA. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Zhang, JJ (reprint author), Univ Calif Santa Cruz, Inst Geophys & Planetary Sci, Santa Cruz, CA 95064 USA. RI Walter, William/C-2351-2013 OI Walter, William/0000-0002-0331-0616 NR 46 TC 5 Z9 8 U1 0 U2 1 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0033-4553 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD AUG PY 2003 VL 160 IS 8 BP 1447 EP 1478 DI 10.1007/s00024-003-2355-7 PG 32 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 689YJ UT WOS:000183520300004 ER PT J AU Farmer, D AF Farmer, D TI Avoiding getting lost in the wilderness of bounded rationality: the path from zero intelligence to no arbitrage SO QUANTITATIVE FINANCE LA English DT Article ID MARKET C1 Los Alamos Natl Lab, Ctr Nonlinear Studies, Div Theoret, Complex Syst Grp, Los Alamos, NM 87545 USA. RP Farmer, D (reprint author), Los Alamos Natl Lab, Ctr Nonlinear Studies, Div Theoret, Complex Syst Grp, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 2 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1469-7688 J9 QUANT FINANC JI Quant. Financ. PD AUG PY 2003 VL 3 IS 4 BP C64 EP C65 PG 2 WC Business, Finance; Economics; Mathematics, Interdisciplinary Applications; Social Sciences, Mathematical Methods SC Business & Economics; Mathematics; Mathematical Methods In Social Sciences GA 725KN UT WOS:000185542500004 ER PT J AU McKeever, SWS Banerjee, D Blair, M Clifford, SM Clowdsley, MS Kim, SS Lamothe, M Lepper, K Leuschen, M McKeever, KJ Prather, M Rowland, A Reust, D Sears, DWG Wilson, JW AF McKeever, SWS Banerjee, D Blair, M Clifford, SM Clowdsley, MS Kim, SS Lamothe, M Lepper, K Leuschen, M McKeever, KJ Prather, M Rowland, A Reust, D Sears, DWG Wilson, JW TI Concepts and approaches to in situ luminescence dating of martian sediments SO RADIATION MEASUREMENTS LA English DT Article; Proceedings Paper CT 10th International Conference on Luminescence and Electron Spin Resonance Dating (LED 2002) CY JUN 24-28, 2002 CL RENO, NEVADA ID POLAR LAYERED DEPOSITS; POLYMINERAL FINE GRAINS; JSC MARS-1; SURFACE; REGION; EARTH; SOIL; PATHFINDER; FELDSPARS; SPACE AB In this paper we present the concept of a robotic instrument for in situ luminescence dating of near-surface sediments on Mars. The scientific objectives and advantages to be gained from the development of such an instrument are described, and the challenges presented by the Mars surface environment to the design and operation of the instrument are outlined. (C) 2003 Published by Elsevier Ltd. C1 Oklahoma State Univ, Arkansas Oklahoma Ctr Space & Planetary Sci, Stillwater, OK 74078 USA. Oklahoma State Univ, Dept Phys, Stillwater, OK 74078 USA. Lunar & Planetary Inst, Houston, TX 77058 USA. NASA, Langley Res Ctr, NRC, Hampton, VA 23681 USA. Jet Prop Lab, Pasadena, CA 91109 USA. Univ Quebec, Dept Sci Terre & Atmosphere, Montreal, PQ H3C 3P8, Canada. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Nomad Inc, Stillwater, OK 74076 USA. Univ Arkansas, Arkansas Oklahoma Ctr Space & Planetary Sci, Fayetteville, AR 72701 USA. Univ Arkansas, Dept Chem, Fayetteville, AR 72701 USA. RP McKeever, SWS (reprint author), Oklahoma State Univ, Arkansas Oklahoma Ctr Space & Planetary Sci, Stillwater, OK 74078 USA. NR 34 TC 26 Z9 26 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1350-4487 J9 RADIAT MEAS JI Radiat. Meas. PD AUG-OCT PY 2003 VL 37 IS 4-5 SI SI BP 527 EP 534 DI 10.1016/S1350-4487(03)00025-8 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 700KD UT WOS:000184110400035 PM 12856693 ER PT J AU Zhong, N Morris, GM Bacarian, T Rosen, EM Dilmanian, EA AF Zhong, N Morris, GM Bacarian, T Rosen, EM Dilmanian, EA TI Response of rat skin to high-dose unidirectional X-ray microbearns: A histological study SO RADIATION RESEARCH LA English DT Article ID RADIATION-THERAPY; SYNCHROTRON-WIGGLER; HAIR-FOLLICLES; STEM-CELLS; SCATTERING; DOSIMETRY; REPAIR; BRAIN AB There is growing interest in evaluating microbeam radiation therapy as a potential clinical modality. Microbeam radiation therapy uses arrays of parallel, microscopically thin (<100 μm) planes of synchrotron-generated X rays (microplanar beams, or microbeams). Due to the relatively low beam energies involved in microbeam radiation therapy (a median beam energy of 120 keV was used in the present study), the dose penetration of microbeams in tissue is lower than that used in conventional radiotherapy. This lower energy necessitates using a significantly elevated dose to the skin's surface during clinical microbeam therapy to ensure an adequate dose distribution in the target tumor. The findings of the present study, using a rat skin model, indicated that the skin had an extremely high tolerance to microbeam radiation at doses considerably in excess of those that were therapeutically effective in preclinical studies. A histological study was undertaken to evaluate the biological mechanisms underlying this high tolerance. The irradiation configuration employed single-exposure, unidirectional microbeams 90 μm wide, with 300 μm beam spacing on-center. The in-beam skin-surface absorbed doses were in the range 835-1335 Gy. Monte Carlo simulations of the dose distribution indicated that the "valley" dose, i.e. the radiation leakage between adjacent microbeams, was about 2.5% of the in-beam dose. The high tolerance of the rats' skin to microbeams and the rapid regeneration of the damaged segments of skin were attributed to the surviving clonogenic cells situated between the adjacent microplanar beams. In the epidermis, clonogenic cells in the hair follicular epithelium appeared to play a key role in the regeneration process. (C) 2003 by Radiation Research Society. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Univ Oxford, Inst Res, Churchill Hosp, Oxford OX3 7LJ, England. Long Isl Jewish Med Ctr, Dept Radiat Oncol, New York, NY 11040 USA. RP Dilmanian, EA (reprint author), Brookhaven Natl Lab, Dept Med, Bldg 490, Upton, NY 11973 USA. NR 22 TC 44 Z9 45 U1 0 U2 2 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD AUG PY 2003 VL 160 IS 2 BP 133 EP 142 DI 10.1667/3033 PG 10 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 703XF UT WOS:000184307000001 PM 12859223 ER PT J AU Carnes, BA Grahn, D Hoel, D AF Carnes, BA Grahn, D Hoel, D TI Mortality of atomic bomb survivors predicted from laboratory animals SO RADIATION RESEARCH LA English DT Article ID RADIATION; CANCER; HUMANS; MOUSE; TIME; RISK AB Exposure, pathology and mortality data for mice, dogs and humans were examined to determine whether accurate inter-species predictions of radiation-induced mortality could be achieved. The analyses revealed that (1) days of life lost per unit dose can be estimated for a species even without information on radiation effects in that species, and (2) accurate predictions of age-specific radiation-induced mortality in beagles and the atomic bomb survivors can be obtained from a dose-response model for comparably exposed mice. These findings illustrate the value of comparative mortality analyses and the relevance of animal data to the study of human health effects. (C) 2003 by Radiation Research Society. C1 Univ Oklahoma, Sch Med, Donald W Reynolds Dept Geriatr Med, Oklahoma City, OK 73190 USA. Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. Med Univ S Carolina, Dept Biometry & Epidemiol, Charleston, SC 29425 USA. RP Carnes, BA (reprint author), Univ Oklahoma, Sch Med, Donald W Reynolds Dept Geriatr Med, Oklahoma City, OK 73190 USA. FU NIA NIH HHS [AG-00577-01] NR 50 TC 14 Z9 15 U1 0 U2 2 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD AUG PY 2003 VL 160 IS 2 BP 159 EP 167 DI 10.1667/RR3029 PG 9 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 703XF UT WOS:000184307000004 PM 12859226 ER PT J AU Menge, PR Johnson, DL Maenchen, JE Rovang, DC Oliver, BV Rose, DV Welch, DR AF Menge, PR Johnson, DL Maenchen, JE Rovang, DC Oliver, BV Rose, DV Welch, DR TI Optimization of a rod pinch diode radiography source at 2.3 MV SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID TRANSPORT AB Rod pinch diodes have shown considerable capability as high-brightness flash x-ray sources for penetrating dynamic radiography. The rod pinch diode uses a small diameter (0.4-2 mm) anode rod extended through a cathode aperture. When properly configured, the electron beam born off of the aperture edge can self-insulate and pinch onto the tip of the rod creating an intense, small x-ray source. Sandia's SABRE accelerator (2.3 MV, 40 Omega, 70 ns) has been utilized to optimize the source experimentally by maximizing the figure of merit (dose/spot diameter2) and minimizing the diode impedance droop. Many diode parameters have been examined including rod diameter, rod length, rod material, cathode aperture diameter, cathode thickness, power flow gap, vacuum quality, and severity of rod-cathode misalignment. The configuration producing the greatest figure of merit uses a 0.5 mm diameter gold rod, a 6 mm rod extension beyond the cathode aperture (diameter=8 mm), and a 10 cm power flow gap to produce up to 3.5 rad (filtered dose) at 1 m from a 0.85 mm x-ray on-axis spot (1.02 mm at 3degrees off axis). The resultant survey of parameter space has elucidated several physics issues that are discussed. (C) 2003 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Mission Res Corp, Kirtland AFB, NM 87117 USA. RP Menge, PR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 21 Z9 21 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 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD AUG PY 2003 VL 74 IS 8 BP 3628 EP 3635 DI 10.1063/1.1589585 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 704NW UT WOS:000184346600004 ER PT J AU Ryutov, DD AF Ryutov, DD TI Thermal stresses in the reflective x-ray optics for the Linac Coherent Light Source SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID DIFFRACTION AB Reflective optics for an intense x-ray beam generated by the planned Linac Coherent Light Source will have to accommodate very high fluence per pulse, at the repetition rate of 120 Hz. We analyze thermal stresses caused by the heating of a thin surface layer of the optics after every pulse. A conclusion is drawn that keeping this stress below the yield strength imposes stringent limitations on the fluence. Possible experiments for evaluating the number of pulses leading to a substantial degradation of the optics due to the thermal fatigue are briefly discussed. (C) 2003 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ryutov, DD (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 12 TC 13 Z9 13 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD AUG PY 2003 VL 74 IS 8 BP 3722 EP 3725 DI 10.1063/1.1590747 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 704NW UT WOS:000184346600022 ER PT J AU Moore, JF Pellin, MJ Calaway, WF Hryn, JN AF Moore, JF Pellin, MJ Calaway, WF Hryn, JN TI Ultraviolet and infrared spectroscopy for effluent analysis in a molten salt electrochemical cell SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID GAS-PHASE; CIGARETTE-SMOKE; IR-SPECTRA; SPECTROELECTROCHEMISTRY; IDENTIFICATION; SPECTROMETRY; KINETICS; DATABASE; PRODUCT; SAMPLE AB An apparatus that combines gas phase spectroscopy over two wavelength ranges for analysis of effluent from a molten salt electrochemical cell is described. The cell is placed in a quartz tube that is sealed at the top with a cap containing feedthrus for power, thermometry, and gas flow. A resistance furnace brings the cell assembly to the desired temperature while the cap remains cooled by water. Inert gas continually purges the cell headspace carrying effluent from the electrolysis sequentially through two gas cells, one in a Fourier transform infrared (FTIR) spectrometer and one in a fiber-optic coupled ultraviolet visible spectrometer. Strong vibrational absorptions in the IR can easily identify common effluent components such as HCl, CO, CO2, and H2O. Electronic bands can identify IR-inactive molecules of importance including Cl-2 and O-2. Since the absorptivity of all of these species is known, determinations of the gas concentration can be made without using standards. Spectra from the electrolysis of molten MgCl2 are shown and discussed, as well as the limit of detection and inherent time resolution of the apparatus as implemented. (C) 2003 American Institute of Physics. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. RP Moore, JF (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Pellin, Michael/B-5897-2008 OI Pellin, Michael/0000-0002-8149-9768 NR 22 TC 1 Z9 1 U1 3 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 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD AUG PY 2003 VL 74 IS 8 BP 3753 EP 3757 DI 10.1063/1.1588745 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 704NW UT WOS:000184346600028 ER PT J AU Zamzow, DS Bajic, SJ Eckels, DE Baldwin, DP Winterrowd, C Keeney, R AF Zamzow, DS Bajic, SJ Eckels, DE Baldwin, DP Winterrowd, C Keeney, R TI Real-time atomic absorption mercury continuous emission monitor SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID AIR-ICP; METALS AB A continuous emission monitor (CEM) for mercury (Hg) in combustor flue gas streams has been designed and tested for the detection of Hg by optical absorption. A sampling system that allows continuous introduction of stack gas is incorporated into the CEM, for the sequential analysis of elemental and total Hg. A heated pyrolysis tube is used in the system to convert oxidized Hg compounds to elemental Hg for analysis of total Hg; the pyrolysis tube is bypassed to determine the elemental Hg concentration in the gas stream. A key component of the CEM is a laboratory-designed and -assembled echelle spectrometer that provides simultaneous detection of all of the emission lines from a Hg pen lamp, which is used as the light source for the optical absorption measurement. This feature allows for on-line spectroscopic correction for interferent gases such as sulfur dioxide and nitrogen dioxide, typically present in combustion stack gas streams, that also absorb at the Hg detection wavelength (253.65 nm). This article provides a detailed description of the CEM system, the characteristics and performance of the CEM, and the results of field tests performed at the Environmental Protection Agency-Rotary Kiln at Research Triangle Park, NC. (C) 2003 American Institute of Physics. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. US EPA, ARCADIS, Durham, NC 27713 USA. RP Zamzow, DS (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. NR 13 TC 7 Z9 7 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 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD AUG PY 2003 VL 74 IS 8 BP 3774 EP 3783 DI 10.1063/1.1589158 PG 10 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 704NW UT WOS:000184346600032 ER PT J AU Emery, K AF Emery, K TI Comment on 'New ways of developing glass/conducting glass/CdS/CdTe/metal thin-film solar cells based on a new model' by Dharmadasa et al 2002 Semicond. Sci. Technol. 17 1238-48 SO SEMICONDUCTOR SCIENCE AND TECHNOLOGY LA English DT Editorial Material AB Current densities under standard 1-sun terrestrial reporting conditions over 60 mA cm(-2) are not physically possible for CdTe (Dharmadasa et al 2002 Semicond. Sci. Technol. 17 1238). This comment discusses why the reported current density and efficiency should be considered erroneous and not an improvement over existing CdTe cells. C1 NREL, Golden, CO USA. RP Emery, K (reprint author), NREL, 1617 Cole Blvd, Golden, CO USA. NR 7 TC 0 Z9 0 U1 10 U2 11 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0268-1242 J9 SEMICOND SCI TECH JI Semicond. Sci. Technol. PD AUG PY 2003 VL 18 IS 8 BP 812 EP 812 AR PII S0268-1242(03)57528-9 DI 10.1088/0268-1242/18/8/401 PG 1 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA 716QT UT WOS:000185040400016 ER PT J AU Nichols, JM Todd, MD Wait, JR AF Nichols, JM Todd, MD Wait, JR TI Using state space predictive modeling with chaotic interrogation in detecting joint preload loss in a frame structure experiment SO SMART MATERIALS & STRUCTURES LA English DT Article ID VIBRATION FAULT-DIAGNOSIS; ROLLING ELEMENT BEARINGS; DAMAGE DETECTION; CORRELATION DIMENSION; TIME-SERIES; ATTRACTOR; IDENTIFICATION; RECONSTRUCTION; SELECTION; SYSTEMS AB This work explores the role of steady-state dynamic analysis in the vibration-based structural health monitoring field. While more traditional approaches focus on transient or stochastic vibration analysis, the method described here utilizes a geometric portrait of system dynamics to extract information about the steady-state response of the structure to sustained excitation. The approach utilizes the fundamental properties of chaotic signals to produce low-dimensional response data which are then analyzed for features which indicate the degree to which the dynamics have been altered by damage. A discussion of the fundamental issues involved in the approach is presented along with experimental evidence of the approach's ability to discriminate among several damage scenarios. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Calif San Diego, Dept Struct Engn, La Jolla, CA 92093 USA. Los Alamos Natl Lab, WR, ESA, Weap Response Grp, Los Alamos, NM 87545 USA. RP Nichols, JM (reprint author), USN, Res Lab, Code 5673, Washington, DC 20375 USA. NR 51 TC 53 Z9 54 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0964-1726 J9 SMART MATER STRUCT JI Smart Mater. Struct. PD AUG PY 2003 VL 12 IS 4 BP 580 EP 601 AR PII S0964-1726(03)63285-4 DI 10.1088/0964-1726/12/4/310 PG 22 WC Instruments & Instrumentation; Materials Science, Multidisciplinary SC Instruments & Instrumentation; Materials Science GA 717JU UT WOS:000185086000010 ER PT J AU Osterwald, CR McMahon, TJ del Cueto, JA AF Osterwald, CR McMahon, TJ del Cueto, JA TI Electrochemical corrosion of SnO2 : F transparent conducting layers in thin-film photovoltaic modules SO SOLAR ENERGY MATERIALS AND SOLAR CELLS LA English DT Article DE photovoltaics; thin-film modules; electrochemical corrosion; tin oxide; leakage currents AB We report on a degradation mechanism in thin-film photovoltaic (PV) modules activated by damp heat and voltages similar in magnitude to those generated by PV modules in power generation systems. This mechanism, which appears to be an electrochemical process involving the soda-lime glass superstrate with its conductive SnO2:F layer, can be greatly accelerated by subjecting modules to elevated temperatures and humidity, both of which increase the leakage currents between the frame and the active PV layers. Water vapor can affect the module damage in two ways: (1) by enhancing leakage currents, and (2) by entering through the module edges, it appears to promote the chemical reaction responsible for the SnO2 corrosion. Damage has been found to occur in both a-Si and CdTe modules. (C) 2002 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Osterwald, CR (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 8 TC 42 Z9 45 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0248 J9 SOL ENERG MAT SOL C JI Sol. Energy Mater. Sol. Cells PD AUG PY 2003 VL 79 IS 1 BP 21 EP 33 AR PII S0927-0248(02)00363-X DI 10.1016/S0927-0248(02)00363-X PG 13 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 716PX UT WOS:000185038500002 ER PT J AU Wu, J Walukiewicz, W Yu, KM Ager, JW Li, SX Haller, EE Lu, H Schaff, WJ AF Wu, J Walukiewicz, W Yu, KM Ager, JW Li, SX Haller, EE Lu, H Schaff, WJ TI Universal bandgap bowing in group-III nitride alloys SO SOLID STATE COMMUNICATIONS LA English DT Article DE semiconductors; optical properties; light absorption and reflection ID CHEMICAL-VAPOR-DEPOSITION; OPTICAL-PROPERTIES; GAP; INN; DEPENDENCE; ALXGA1-XN; AL1-XINXN; EPITAXY; GROWTH; ENERGY AB The energy gaps of molecular-beam-epitaxy grown wurtzite-structure In1-xAlxN alloys with x less than or equal to 0.25 have been measured by absorption and photoluminescence experiments. The results are consistent with the recent discovery of a narrow bandgap of similar to0.7 eV for InN. A bowing parameter of 3 eV was determined from the composition dependence of these bandgaps. Combined with previously reported data of InGaN and GaAlN, these results show a universal relationship between the bandgap variations of group-III nitride alloys and their compositions. Published by Elsevier Ltd. C1 Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Appl Sci & Technol Grad Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Cornell Univ, Dept Elect & Comp Engn, Ithaca, NY 14853 USA. RP Wu, J (reprint author), Lawrence Berkeley Natl Lab, Div Sci Mat, 1 Cyclotron Rd,MS 2R0200, Berkeley, CA 94720 USA. EM jwu@lbl.gov; w_walukiewicz@lbl.gov RI Wu, Junqiao/G-7840-2011; Yu, Kin Man/J-1399-2012; OI Wu, Junqiao/0000-0002-1498-0148; Yu, Kin Man/0000-0003-1350-9642; Ager, Joel/0000-0001-9334-9751 NR 20 TC 61 Z9 61 U1 1 U2 19 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD AUG PY 2003 VL 127 IS 6 BP 411 EP 414 DI 10.1016/S0038-1098(03)00457-5 PG 4 WC Physics, Condensed Matter SC Physics GA 710KA UT WOS:000184678300002 ER PT J AU Eom, J Aumentado, J Chandrasekhar, V Baldo, PM Rehn, LE AF Eom, J Aumentado, J Chandrasekhar, V Baldo, PM Rehn, LE TI Superconducting proximity effect in the presence of strong spin scattering SO SOLID STATE COMMUNICATIONS LA English DT Article DE superconductors; heterojunctions; kondo effects; electronic transport ID SIZE DEPENDENCE; RESISTANCE; RESISTIVITY; REENTRANCE; TRANSPORT; ABSENCE; MAXIMUM; DEVICES; GLASS; WIRES AB We report measurements of the four terminal temperature dependent resistance of narrow An wires implanted with 100 ppm Fe impurities in proximity to superconducting Al films. The wires show an initial decrease in resistance as the temperature is lowered through the superconducting transition of the Al films, but then show an increase in resistance as the temperature is lowered further. In contrast to the case of pure An wires in contact with a superconducting film, the resistance at the lowest temperatures rises above the normal state resistance. Analysis of the data shows that, in addition to contributions from magnetic scattering and electron-electron interactions, the temperature dependent resistivity shows a substantial contribution from the superconducting proximity effect, which exists even in the presence of strong spin scattering. Published by Elsevier Ltd. C1 Sejong Univ, Dept Phys, Seoul 143747, South Korea. Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RP Sejong Univ, Dept Phys, Kunja Dong 98, Seoul 143747, South Korea. EM eom@sejong.ac.kr RI Aumentado, Jose/C-2231-2009 OI Aumentado, Jose/0000-0001-5581-1466 NR 26 TC 2 Z9 2 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1098 EI 1879-2766 J9 SOLID STATE COMMUN JI Solid State Commun. PD AUG PY 2003 VL 127 IS 8 BP 545 EP 549 DI 10.1016/S0038-1098(03)00488-5 PG 5 WC Physics, Condensed Matter SC Physics GA 716PY UT WOS:000185038600004 ER PT J AU Kim, J Ren, F Baca, AG Briggs, RD Pearton, SJ AF Kim, J Ren, F Baca, AG Briggs, RD Pearton, SJ TI High temperature thermal stability of Au/Ti/WSix Schottky contacts on n-type 4H-SiC SO SOLID-STATE ELECTRONICS LA English DT Article ID OHMIC CONTACTS; SILICON-CARBIDE; DIODE FORMATION; TUNGSTEN; GAN AB The thermal stability of Au/Ti/WSi, contacts on 4H-SiC was examined by Auger electron spectroscopy and current voltage measurements. The silicide-based contacts on SiC are found to exhibit improved thermal stability compared to pure W contacts. The Au/Ti/WSix contacts show a maximum Schottky barrier height of similar to1.15 eV as obtained from current-voltage (I-V) measurements. After 500degreesC anneals, the Ti diffuses to the surface of the contact structure, followed by a Au-rich layer and finally the WSix. After 1000degreesC anneals, the Ti and Au showed significant mixing. Particulates formed on the surface in the latter case were Au-rich phases. (C) 2003 Elsevier Science Ltd. All rights reserved. C1 Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. RP Ren, F (reprint author), Univ Florida, Dept Chem Engn, POB 116005, Gainesville, FL 32611 USA. RI Kim, Jihyun/F-6940-2013 NR 24 TC 4 Z9 4 U1 2 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1101 J9 SOLID STATE ELECTRON JI Solid-State Electron. PD AUG PY 2003 VL 47 IS 8 BP 1345 EP 1350 DI 10.1016/S0038-1101(03)00069-8 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 684VD UT WOS:000183226500011 ER PT J AU Iuliucci, RJ Clawson, J Hu, JZ Solum, MS Barich, D Grant, DM Taylor, CMV AF Iuliucci, RJ Clawson, J Hu, JZ Solum, MS Barich, D Grant, DM Taylor, CMV TI Ring-chain tautomerism in solid-phase erythromycin A: evidence by solid-state NMR SO SOLID STATE NUCLEAR MAGNETIC RESONANCE LA English DT Article DE erythromycin; solid-state NMR; magic-angle turning; dipolar-dephasing; chemical shift; chemical shielding; hemiketal; density functional theory ID CHEMICAL-SHIFT TENSORS; SINGLE-CRYSTAL; C-13 NMR; SPECTROSCOPY; RESOLUTION; DENSITY; SPECTRA; H-1 AB Chemical shift modeling, utilizing the DFT B3LYP/D95** method, provides the spectral assignment of the 35 visible C-13 resonances from the solid-phase erythromycin A dihydrate. A new resonance at 110.8ppm is observed in the high-resolution (13) CP/MAS spectrum upon the application of heat or sample desiccation. With the use of the dipolar-dephasing spectral editing technique, this resonance is identified as a hemiketal carbon and the alternative hypothesis, a conformational change to the anomeric carbon of the desosamine sugar, is ruled out. Hence, the formation of a cyclic hemiketal in erythromycin A while in the solid phase is proven by solid-state NMR. The principal components of the C-13 chemical-shift tensor corresponding to this hemiketal are reported. This is the first measurement of hemiketal C-13 principal values. The delta(11) and delta(22) components are unique compared to anomeric carbon values reported in the literature. (C) 2003 Elsevier Science (USA). All rights reserved. C1 Washington & Jefferson Coll, Dept Chem, Washington, PA 15301 USA. Univ Utah, Dept Chem, Salt Lake City, UT 84116 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Iuliucci, RJ (reprint author), Washington & Jefferson Coll, Dept Chem, Washington, PA 15301 USA. RI Hu, Jian Zhi/F-7126-2012 FU NIGMS NIH HHS [GM08521-37] NR 32 TC 11 Z9 11 U1 2 U2 10 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0926-2040 J9 SOLID STATE NUCL MAG JI Solid State Nucl. Magn. Reson. PD AUG PY 2003 VL 24 IS 1 BP 23 EP 38 DI 10.1016/S0926-2040(03)00029-8 PG 16 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Spectroscopy SC Chemistry; Physics; Spectroscopy GA 701KQ UT WOS:000184167100002 PM 12850255 ER PT J AU Gupta, A Narayan, H Astill, D Kanjila, D Ferdeghini, C Paranthaman, M Narlikar, AV AF Gupta, A Narayan, H Astill, D Kanjila, D Ferdeghini, C Paranthaman, M Narlikar, AV TI Study of magnetization and pinning mechanisms in MgB2 thin film superconductors: effect of heavy ion irradiation SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID PULSED-LASER DEPOSITION; MAGNESIUM DIBORIDE; WIRES AB We report magnetization studies on MgB2 superconducting thin films in a temperature range 4.2-40 K and magnetic field range 0-6 T. Thin films prepared by both pulsed laser deposition (PLD) and electron beam evaporation (EBE) methods were investigated. In addition, both films were studied before and after heavy ion irradiation by 200 MeV Ag ions with a dose of 1011 ions cm(-2). Variation of sweep rates during the measurement of the magnetization loop reveals the presence of flux creep in both films. The PLD film, after irradiation, shows a severe degradation of T, critical current densities (J(c)) in low fields and irreversibility line (B*(T)). In contrast, the EBE film shows a slight enhancement in T-c, and nearly no change in Je(B) and the position of irreversibility line after irradiation. For both pristine films, the obtained volume pinning forces F-p versus reduced field b = B/B* shows a good scaling for T less than or equal to 10 K, which matches well with the theoretical curve based on the flux line shear (FLS) pinning model. These and other results can be interpreted in terms of grain boundaries in MgB2 films acting as FLS channels. C1 Natl Phys Lab, New Delhi 110012, India. IRCS, Cavendish Lab, Cambridge, England. Ctr Nucl Sci, New Delhi 110067, India. INFM, Dipartimento Fis, I-16146 Genoa, Italy. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. IUC DAE Facil, Indore 452001, India. RP Gupta, A (reprint author), Natl Phys Lab, Dr Krishnan Rd, New Delhi 110012, India. RI Kanjilal, Dinakar/D-4731-2013; Paranthaman, Mariappan/N-3866-2015; OI Kanjilal, Dinakar/0000-0001-9728-3147; Paranthaman, Mariappan/0000-0003-3009-8531; FERDEGHINI, CARLO/0000-0003-0323-7719 NR 19 TC 17 Z9 17 U1 0 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD AUG PY 2003 VL 16 IS 8 BP 951 EP 955 AR PII S0953-2048(03)63538-4 DI 10.1088/0953-2048/16/8/322 PG 5 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 716QJ UT WOS:000185039600023 ER PT J AU Barrow, JA Fournee, V Ross, AR Thiel, PA Shimoda, M Tsai, AP AF Barrow, JA Fournee, V Ross, AR Thiel, PA Shimoda, M Tsai, AP TI Photoemission studies of the sputter-induced phase transformation on the Al-Cu-Fe surface SO SURFACE SCIENCE LA English DT Article DE reflection high-energy electron diffraction (RHEED); X-ray photoelectron spectroscopy; visible and ultraviolet photoelectron spectroscopy; ion etching; sputtering; surface relaxation and reconstruction ID MN FIVEFOLD SURFACE; QUASI-CRYSTALS; PD-MN; ELECTRONIC-STRUCTURE; DYNAMICAL LEED; SPECTROSCOPY; SUBSTRATE; SYMMETRY; ALCUFE; ALLOYS AB The surface of a single grain icosahedral (i) Al-Cu-Fe quasicrystalline sample is studied as a function of annealing temperature using ultra-violet photoemission spectroscopy (UPS). Reflection high-energy electron diffraction and X-ray photoelectron spectroscopy are also performed to verify surface structure and composition. The sputtered surface shows structure and chemical composition consistent with that of beta-Al-Cu-Fe cubic phase together with a sharp Fermi cut-off. With increasing annealing temperature, the surface structure and composition reverts to that of the quasicrystal. This transformation is correlated with a decrease of the spectral intensity at the Fermi level (E-F). Analysis of the UPS spectra in the region near E-F is performed by fitting the data with a pseudogap function. (C) 2003 Elsevier B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Ecole Mines, CNRS, UMR7584, LSG2M, F-54042 Nancy, France. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Natl Inst Mat Sci, Tsukuba, Ibaraki 3050047, Japan. RP Iowa State Univ Sci & Technol, Dept Chem, 225 Spedding Hall, Ames, IA 50011 USA. EM jabarrow@iastate.edu OI Shimoda, Masahiko/0000-0002-6822-2836 NR 37 TC 12 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 EI 1879-2758 J9 SURF SCI JI Surf. Sci. PD AUG 1 PY 2003 VL 539 IS 1-3 BP 54 EP 62 DI 10.1016/S0039-6028(03)00746-5 PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 708TK UT WOS:000184585300017 ER PT J AU Busse, C Langenkamp, W Polop, C Petersen, A Hansen, H Linke, U Feibelman, PJ Michely, T AF Busse, C Langenkamp, W Polop, C Petersen, A Hansen, H Linke, U Feibelman, PJ Michely, T TI Dimer binding energies on fcc(111) metal surfaces SO SURFACE SCIENCE LA English DT Article DE density functional calculations; scanning tunneling microscopy; iridium; aluminum; low index single crystal surfaces; adatoms ID WAVE BASIS-SET; SELF-DIFFUSION; MOLECULAR-DYNAMICS; ULTRASOFT PSEUDOPOTENTIALS; CLUSTER DISSOCIATION; IR-X; PT(111); GROWTH; TRANSITION; ELECTRON AB Analysis of island density vs. temperature, observed in scanning tunneling microscopy, implies that the binding energy of a self-adsorbed dimer equals 0.11-0.12 of the cohesive energy on Ir(I 11), AI(I 1 1), and Pt(1 11). While ab initio calculations scatter around the experimental results by about 20%, field ion microscopy of Ir(I 11) and Pt(I 11) yields dimer binding energies nearly a factor of three smaller than the corresponding scanning tunneling microscopy results. On the basis of ab initio calculations, these low values are attributed to the neglect of dimer dissociation processes at step edges. (C) 2003 Elsevier B.V. All rights reserved. C1 Rhein Westfal TH Aachen, Inst Phys 1, D-52056 Aachen, Germany. Forschungszentrum Julich, D-52425 Julich, Germany. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Busse, C (reprint author), Rhein Westfal TH Aachen, Inst Phys 1, D-52056 Aachen, Germany. EM busse@physik.rwth-aachen.de RI Busse, Carsten/A-7485-2008; Petersen, Ansgar/O-1945-2015 OI Busse, Carsten/0000-0001-5522-0578; NR 41 TC 20 Z9 20 U1 1 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD AUG 1 PY 2003 VL 539 IS 1-3 BP L560 EP L566 DI 10.1016/S0039-6028(03)00814-8 PG 7 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 708TK UT WOS:000184585300008 ER PT J AU Zhong, HX Wells, JC Niu, Q Zhang, ZY AF Zhong, HX Wells, JC Niu, Q Zhang, ZY TI Dependence of surface strain on island geometry in embedded quantum-dot systems SO SURFACE SCIENCE LA English DT Article DE growth; self-assembly; surface stress; molecular beam epitaxy ID SELF-ORGANIZED GROWTH; LATERAL CORRELATIONS; SUPERLATTICES; STRESS; GAAS; MATRIX; FILMS; GE AB Strain fields induced by embedded islands of pyramidal shape are examined using the continuum theory of elasticity with Ge/Si systems as a specific example. We show that, upon increasing spacer thickness, the decay of the strain field on the spacer surface undergoes a crossover from a non-cubic inverse power law to a cubic inverse power law. The exponent for the non-cubic inverse power law depends on island slope with a smaller exponent corresponding to a smaller slope. Additionally, the strain is nearly proportional to the island volume when the slope is large but to the island area when the slope is small. These findings reconcile several diverse predictions derived from large-scale atomistic simulations for islands of different geometries. (C) 2003 Elsevier B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Univ Texas, Dept Phys, Austin, TX 78712 USA. Oak Ridge Natl Lab, Condensed Matter Sci Div, Oak Ridge, TN 37831 USA. RP Zhong, HX (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Niu, Qian/G-9908-2013; Wells, Jack/D-3675-2016 OI Wells, Jack/0000-0002-5083-3030 NR 28 TC 3 Z9 3 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD AUG 1 PY 2003 VL 539 IS 1-3 BP L525 EP L530 DI 10.1016/S0039-6028(03)00784-2 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 708TK UT WOS:000184585300002 ER PT J AU Miraglia, PQ Preble, EA Roskowski, AM Einfeldt, S Lim, SH Liliental-Weber, Z Davis, RF AF Miraglia, PQ Preble, EA Roskowski, AM Einfeldt, S Lim, SH Liliental-Weber, Z Davis, RF TI Helical-type surface defects in InGaN thin films epitaxially grown on GaN templates at reduced temperatures SO THIN SOLID FILMS LA English DT Article DE surface defects; atomic force microscopy; metalorganic vapor phase epitaxy; indium gallium nitride ID MULTIPLE-QUANTUM WELLS; CHEMICAL-VAPOR-DEPOSITION; V-DEFECTS; FORMATION MECHANISM; MULTIQUANTUM WELLS; OPTICAL-PROPERTIES; PHASE EPITAXY; PIT FORMATION; LAYERS; MORPHOLOGY AB The surface morphologies of InGaN films grown at 780 degreesC by metalorganic vapor phase epitaxy were determined using atomic force microscopy. A qualitative model was developed to explain the observed instabilities in the step morphology of these films, namely, the formation of hillocks and v-defects that give rise to surface roughening. V-defects, observed at a surface density greater than 2 X 10(8)/cm(2) are a result of interactions between moving surface steps, cores of screw-type dislocations, and two-dimensional islands of atoms that form on the terraces during growth at high surface undercooling. A delay in the formation of v-defects in InGaN to a nominal thickness of 10 nm was observed and associated with the ammonia partial pressure and the interactions between steps associated with hillock islands and cores of screw-type dislocations. Hillock formation was attributed to a transition in the thermodynamic mode of film growth, as three-dimensional islands nucleated on the cores of screw-type dislocations at a density of 2 X 10(8)/cm(2). Explanations for the foregoing observations are based on growth model theory previously developed by Burton, Cabrera and Frank and on changes in the surface kinetics with temperature, In composition, and gas phase composition. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Northeastern Univ, Snell Engn Labs 147, Dept Chem Engn, Egan Res Ctr 250, Boston, MA 02115 USA. N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. N Carolina State Univ, Dept Chem Engn, Raleigh, NC 27695 USA. Univ Bremen, Inst Solid State Phys, D-28334 Bremen, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Miraglia, PQ (reprint author), Northeastern Univ, Snell Engn Labs 147, Dept Chem Engn, Egan Res Ctr 250, Boston, MA 02115 USA. RI Liliental-Weber, Zuzanna/H-8006-2012; Davis, Robert/A-9376-2011 OI Davis, Robert/0000-0002-4437-0885 NR 40 TC 8 Z9 8 U1 0 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD AUG 1 PY 2003 VL 437 IS 1-2 BP 140 EP 149 AR PII S0040-6090(03)00611-4 DI 10.1016/S0040-6090(03)00611-4 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 704XU UT WOS:000184367600021 ER PT J AU DeSanto, P Buttrey, DJ Grasselli, RK Lugmair, CG Volpe, AF Toby, BH Vogt, T AF DeSanto, P Buttrey, DJ Grasselli, RK Lugmair, CG Volpe, AF Toby, BH Vogt, T TI Structural characterization of the orthorhombic phase M1 in MoVNbTeO propane ammoxidation catalyst SO TOPICS IN CATALYSIS LA English DT Article; Proceedings Paper CT 2nd Symposium on Multifunctionality of Catalytically Active Sites and Their Detection CY JUN, 2002 CL SCHWABISCHES BILDUNGSZENTRUM, KLOSTER IRSEE, GERMANY SP Robert Karl Grasselli Fdn HO SCHWABISCHES BILDUNGSZENTRUM DE MoVNbTeO; propane; ammoxidation; acrylonitrile; out-of-center; distortion; site isolation; molybdates; mixed-metal; multifunctionality; catalyst; Rietveld; refinement; Magneli phase; channel structure ID OXYGEN BOND DISTANCES; TERNARY PHASES; MO5O14 TYPE; SELECTIVE OXIDATION; VANADIUM PENTOXIDE; RAMAN-SPECTROSCOPY; CRYSTAL-STRUCTURE; SYSTEM; TRANSITION; OXIDES AB The structure of the orthorhombic phase in the MoVNbTeO propane ammoxidation catalyst system has been characterized and refined using a combination of TEM, synchrotron X-ray powder diffraction (S-XPD), and neutron powder diffraction (NPD). This phase, designated as M1 by Ushikubo et al. [1], crystallizes in the orthorhombic space group Pba2 (No. 32) with a = 21.134(2) Angstrom b = 26.658(2) Angstrom, and c = 4.0146(3) Angstrom. The formula unit is Mo7.5V1.5NbTeO29. Bond valence sum calculations indicate the presence of d(1) metal sites neighbored by d(0) metal sites. The d(1) sites are occupied by a distribution of Mo5+ and V4+, whereas the d(0) sites are occupied by a distribution of Mo6+ and V5+. Out-of-center distortions in d(0) octahedra are consistent with the second- order Jahn-Teller effect and lattice effects. We argue that the V5+-O-V4+/Mo5+ moieties adjacent to Te4+ and Mo6+ sites in the [001] terminal plane provide a spatially isolated active site at which the selective ammoxidation of propane occurs. C1 Univ Delaware, Ctr Catalyt Sci & Technol, Dept Chem Engn, Newark, DE 19716 USA. Symyx Technol Inc, Catalysis Grp, Santa Clara, CA 95051 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Buttrey, DJ (reprint author), Univ Delaware, Ctr Catalyt Sci & Technol, Dept Chem Engn, Newark, DE 19716 USA. RI Vogt, Thomas /A-1562-2011; Toby, Brian/F-3176-2013 OI Vogt, Thomas /0000-0002-4731-2787; Toby, Brian/0000-0001-8793-8285 NR 42 TC 134 Z9 135 U1 1 U2 13 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1022-5528 J9 TOP CATAL JI Top. Catal. PD AUG PY 2003 VL 23 IS 1-4 BP 23 EP 38 DI 10.1023/A:1024812101856 PG 16 WC Chemistry, Applied; Chemistry, Physical SC Chemistry GA 704JP UT WOS:000184336800004 ER PT J AU Ress, NB Chou, BJ Renne, RA Dill, JA Miller, RA Roycroft, JH Hailey, JR Haseman, JK Bucher, JR AF Ress, NB Chou, BJ Renne, RA Dill, JA Miller, RA Roycroft, JH Hailey, JR Haseman, JK Bucher, JR TI Carcinogenicity of inhaled vanadium pentoxide in F344/N rats and B6C3F(1) mice SO TOXICOLOGICAL SCIENCES LA English DT Article DE carcinoma; adenoma; soluble particles; lung; vanadium pentoxide; vanadium; reactive-oil-fly-ash (ROFA); inflammation; fibrosis; boilermaker's bronchitis ID FREE-RADICAL REACTIONS; ZERO DOSE CONTROL; NF-KAPPA-B; 2'-DEOXYGUANOSINE HYDROXYLATION; DIET NTP-2000; INDUCTION; TOXICOLOGY; ACTIVATION; CELLS; MACROPHAGES AB Vanadium pentoxide (V2O5) is a slightly soluble compound found in airborne particle emissions from metallurgical works and oil and coal burning. Because the carcinogenic potential of V2O5 was not known, F344/N rats and B6C3F(1) mice (N = 50/sex/ species) were exposed to V2O5 at concentrations of 0, 0.5 (rats only), 1, 2, or 4 (mice only) mg/m(3), by whole-body inhalation for 2 years. The survival and body weights of rats were minimally affected by exposure to V2O5. The survival and body weights of male mice exposed to 4 mg/m(3) and body weights of all exposed groups of female mice were lower than the controls. Alveolar/ bronchiolar (A/B) neoplasms occurred in male rats exposed to 0.5 and 2 mg/m(3) at incidences exceeding the National Toxicology Program (NTP) historical control ranges. A marginal increase in A/B neoplasms was also observed in female rats exposed to 0.5 mg/m(3). Increases in chronic inflammation, interstitial fibrosis, and alveolar and bronchiolar hyperplasia/metaplasia and squamous metaplasia were observed in exposed male and female rats. A/B neoplasms were significantly increased in all groups of exposed mice. As with rats, increases in chronic inflammation, interstitial fibrosis, and alveolar and bronchiolar epithelial hyperplasia were observed in mice exposed to V2O5. Thus, V2O5 exposure was a pulmonary carcinogen in male rats and male and female mice. The marginal tumor response in the lungs of female rats could not be attributed conclusively to exposure to V2O5. These responses were noted at and slightly above the OSHA permissible occupational exposure limit of 0.5 mg/m(3) (dust) (National Institute for Occupational Safety and Health, NIOSH Pocket Guide to Chemical Hazards, U.S. Department of Health and Human Services, Washington, DC, 1997, p. 328). C1 NIEHS, Natl Toxicol Program, Res Triangle Pk, NC 27709 USA. Battelle Toxicol NW, Richland, WA 99352 USA. RP Bucher, JR (reprint author), NIEHS, Natl Toxicol Program, 79 Alexander Dr,Mail Drop EC-34, Res Triangle Pk, NC 27709 USA. NR 46 TC 46 Z9 49 U1 0 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1096-6080 J9 TOXICOL SCI JI Toxicol. Sci. PD AUG PY 2003 VL 74 IS 2 BP 287 EP 296 DI 10.1093/toxsci/kfg136 PG 10 WC Toxicology SC Toxicology GA 705LU UT WOS:000184397200010 PM 12773761 ER PT J AU Radisky, DC Hirai, Y Bissell, MJ AF Radisky, DC Hirai, Y Bissell, MJ TI Delivering the message: epimorphin and mammary epithelial morphogenesis SO TRENDS IN CELL BIOLOGY LA English DT Review ID FIBROBLAST GROWTH-FACTOR; INDUCED PULMONARY FIBROSIS; CANINE KIDNEY-CELLS; IN-VITRO; BRANCHING MORPHOGENESIS; MOLECULAR-MECHANISMS; PLATELET EXOCYTOSIS; GLAND DEVELOPMENT; MATRIX METALLOPROTEINASES; SYNTAXIN 2 AB The mammary gland consists of a highly branched tubular epithelium surrounded by a complex mesenchymal stroma. Epimorphin is an extracellular protein that is expressed by mammary mesenchymal cells that directs epithelial morphogenesis. Depending upon the context of presentation - polar versus apolar - epimorphin can selectively direct two key processes of tubulogenesis: branching morphogenesis (processes involved in tubule initiation and extension) and luminal morphogenesis (required for enlargement of tubule caliber). Here, we outline the fundamentals of mammary gland development and describe the function of epimorphin in these processes. We conclude with a review of recent studies that suggest similar morphogenic roles for epimorphin in other glandular organs. C1 Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. Sumitomo Elect Ind Ltd, Osaka R&D Lab, Yokohama Lab, Yokohama, Kanagawa, Japan. RP Bissell, MJ (reprint author), Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. FU NCI NIH HHS [R01 CA057621, CA 57621, R01 CA057621-07] NR 111 TC 51 Z9 52 U1 2 U2 9 PU ELSEVIER SCIENCE LONDON PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0962-8924 J9 TRENDS CELL BIOL JI Trends Cell Biol. PD AUG PY 2003 VL 13 IS 8 BP 426 EP 434 DI 10.1016/S0962-8924(03)00146-6 PG 9 WC Cell Biology SC Cell Biology GA 711FV UT WOS:000184729700007 PM 12888295 ER PT J AU Oldenburg, CM Unger, AJA AF Oldenburg, Curtis M. Unger, Andre J. A. TI On Leakage and Seepage from Geologic Carbon Sequestration Sites: Unsaturated Zone Attenuation SO VADOSE ZONE JOURNAL LA English DT Article AB Geologic carbon sequestration is the direct injection of CO(2) into deep geologic formations for permanent disposal. Although numerous trapping mechanisms exist in the subsurface, it is possible that CO(2) will leak from the primary sequestration target and seep out of the ground. The unsaturated zone has the potential to attenuate leaking CO(2) and decrease seepage and near-surface CO(2) concentrations. Attenuation processes include permeability trapping, ponding as dense CO(2) spreads out on the water table, solubility trapping by infiltrating or residual water, and dilution through mixing with ambient soil gas. Numerical simulations of CO(2) flowing upward through a thick model unsaturated zone were performed to investigate the sensitivity of various unsaturated zone properties on CO(2) seepage flux and near-surface CO(2) gas concentrations. These two quantities are considered drivers for health and environmental risk due to exposure to CO(2). For the conceptual model considered, seepage flux and near-surface CO(2) gas concentrations are most strongly controlled by the leakage rate at the water table, followed by the source zone radius. Permeability and permeability anisotropy, as well as porosity and infiltration rate are also important, although to a lesser degree. Barometric pumping causes local maxima in seepage flux and near-surface CO(2) concentrations, but has negligible effect in a time-averaged sense. When the leakage source is turned off, the CO(2) plume attentuates through dissolution into infiltrating water. For the case of a constant leakage rate, the unsaturated zone can attenuate low leakage fluxes but should not be expected to attenuate large CO(2) leakage fluxes. C1 [Oldenburg, Curtis M.; Unger, Andre J. A.] Univ Calif Berkeley, Lawrence Berkeley Lab, Earth Sci Div 90 1116, Berkeley, CA 94720 USA. RP Oldenburg, CM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Earth Sci Div 90 1116, Berkeley, CA 94720 USA. EM cmoldenburg@lbl.gov RI Oldenburg, Curtis/L-6219-2013 OI Oldenburg, Curtis/0000-0002-0132-6016 FU Cooperative Research and Development Agreement (CRADA) FX We thank Karsten Pruess and Christine Doughty (LBNL) for constructive review comments, and Sally Benson, Marcelo Lippmann, Robert Hepple, and Preston Jordan (all LBNL) for stimulating discussions that helped focus the study. This work was supported in part by a Cooperative Research and Development Agreement (CRADA) between BP Corporation North America, as part of the CO2 Capture Project (CCP) of the Joint Industry Program (JIP), and the U. S. Department of Energy (DOE) through the National Energy Technologies Laboratory (NETL), and by the Office of Science, U.S. Department of Energy under contract DE-AC03-76SF00098. NR 23 TC 69 Z9 72 U1 0 U2 13 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 1539-1663 J9 VADOSE ZONE J JI Vadose Zone J. PD AUG PY 2003 VL 2 IS 3 BP 287 EP 296 PG 10 WC Environmental Sciences; Soil Science; Water Resources SC Environmental Sciences & Ecology; Agriculture; Water Resources GA V11VA UT WOS:000207557900002 ER PT J AU Zhang, ZF Ward, AL Gee, GW AF Zhang, Z. Fred Ward, Andy L. Gee, Glendon W. TI A Tensorial Connectivity-Tortuosity Concept to Describe the Unsaturated Hydraulic Properties of Anisotropic Soils SO VADOSE ZONE JOURNAL LA English DT Article AB The anisotropy in unsaturated hydraulic conductivity is saturation dependent. Yet, there are few options for modeling this phenomenon in natural soils. A tensorial connectivity-tortuosity (TCT) concept is proposed to describe the unsaturated soil hydraulic conductivity. The TCT concept assumes that soil pore connectivity and/or tortuosity are anisotropic and can be described using a tensor. Saturation-dependent anisotropy can be easily invoked in common models of relative permeability by incorporating the connectivity tensor. Synthetic Miller-similar soils having hypothetical anisotropy are defined by allowing the saturated hydraulic conductivity to have different correlation range for different directions of flow. The TCT concept was tested using the synthetic soils with four levels of heterogeneity and four levels of anisotropy. The results show that the soil water retention curves were independent of flow direction but dependent on soil heterogeneity, while the connectivity-tortuosity coefficient is a function of both soil heterogeneity and anisotropy. The TCT model can accurately describe the unsaturated hydraulic functions of anisotropic soils and can be easily combined with commonly used relative permeability functions for use in numerical solutions of the flow equation. C1 [Zhang, Z. Fred; Ward, Andy L.; Gee, Glendon W.] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Zhang, ZF (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM fred.zhang@pnl.gov FU Office of Science, U.S. Department of Energy; Battelle [DE-AC06-76RL01830] FX Funding for this research was provided by the Environmental Management Science Program of the Office of Science, U.S. Department of Energy. The Pacific Northwest National Laboratory is operated for the U.S. Department of Energy by Battelle under Contract DE-AC06-76RL01830. NR 31 TC 24 Z9 24 U1 0 U2 6 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 1539-1663 J9 VADOSE ZONE J JI Vadose Zone J. PD AUG PY 2003 VL 2 IS 3 BP 313 EP 321 PG 9 WC Environmental Sciences; Soil Science; Water Resources SC Environmental Sciences & Ecology; Agriculture; Water Resources GA V11VA UT WOS:000207557900004 ER PT J AU Tokunaga, TK Olson, KR Wan, JM AF Tokunaga, Tetsu K. Olson, Keith R. Wan, Jiamin TI Moisture Characteristics of Hanford Gravels: Bulk, Grain-Surface, and Intragranular Components SO VADOSE ZONE JOURNAL LA English DT Article AB their unsaturated hydraulic properties have received relatively little attention. This study examines moisture retention relations in the 2- and 6-mm size fractions of gravels from the Hanford formation vadose zone (Washington State). Understanding flow and transport within this formation is important because parts of it have become contaminated by leakage of radioactive wastes at the Hanford Site. Moisture retention relations were obtained for a very wide energy range, with attention to water retained in intragranular pores and along grain surfaces. External surfaces of these gravels have root mean-squared roughnesses (rmsr) in the micrometer range, with sparsely distributed deep (hundreds of micrometers) pits. Water films on these external surfaces are volumetrically insignificant at matric potentials less than about -2 kPa. Residual water in these gravels occurs in intragranular pores, accounts for about 10% of the total porosity, and is effectively hydraulically immobile. The intragranular domain in Hanford gravels also has a large specific surface area of about 11 m(2) g(-1). Thus, exchanges of solutes (including contaminants) between the intragranular domain of Hanford gravels and their immediate surrounding are significant and diffusion limited. C1 [Tokunaga, Tetsu K.; Olson, Keith R.; Wan, Jiamin] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Tokunaga, TK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM tktokunaga@lbl.gov RI Tokunaga, Tetsu/H-2790-2014; Wan, Jiamin/H-6656-2014 OI Tokunaga, Tetsu/0000-0003-0861-6128; FU DOE [DE-AC03-76SF00098]; U.S. Department of Energy, Division of Materials Sciences and Division of Chemical Sciences [DE-AC02-98CH10886]; DOE FX Smith, and Bruce Bjornstad of PNNL for samples of Hanford formation sediment. We also thank Sam Ricci, Jr., and Ricci Brothers Sand Company, Port Norris, NJ for providing quartz gravel samples. Helpful internal review comments by Tim Kneafsey (LBNL), and final constructive comments by two anonymous reviewers are gratefully acknowledged. This work was carried out under U.S. Dep. of Energy (DOE) Contract no. DE-AC03-76SF00098, with funding provided by the DOE, Environmental Management Science Program. Research carried out (in part) at the National Synchrotron Light Source, Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Division of Materials Sciences and Division of Chemical Sciences under Contract no. DE-AC02-98CH10886. NR 29 TC 30 Z9 32 U1 0 U2 9 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 1539-1663 J9 VADOSE ZONE J JI Vadose Zone J. PD AUG PY 2003 VL 2 IS 3 BP 322 EP 329 PG 8 WC Environmental Sciences; Soil Science; Water Resources SC Environmental Sciences & Ecology; Agriculture; Water Resources GA V11VA UT WOS:000207557900005 ER PT J AU Wend, CF Stewart, PS Jones, W Camper, AK AF Wend, CF Stewart, PS Jones, W Camper, AK TI Pretreatment for membrane water treatment systems: a laboratory study SO WATER RESEARCH LA English DT Article DE biological treatment; membranes; biofouling; laboratory scale; biofilm; chlorination ID NATURAL ORGANIC-MATTER; IRON-OXIDE; REVERSE-OSMOSIS; SAUDI-ARABIA; ADSORPTION; NOM; PERFORMANCE; FILTRATION; FILTERS; REMOVAL AB The goal of the work was to determine if biological treatment of water containing soil-derived humic substances has the potential for reducing the fouling of membranes used in water treatment. Laboratory scale biological filters containing biologically active carbon or iron oxide coated sand were fed humic-laden water with or without prechlorination. This stream was split, with half being further treated by microfiltration. Treated water was assessed for total organic carbon removal and biofouling potential using a glass bead assay and membrane assay for total cell counts, fouling layer thickness, and flux reduction. A combination of these assays provided more insight than any single measurement. Compared to untreated control water, biological treatment was capable of reducing downstream fouling of membrane systems. For example, fouling layer thickness was reduced by half after biological treatment, and cell counts were reduced four- to five-fold. Biological treatment coupled with microfiltration provided the best reduction of fouling, while prechlorination did not appear to impact the process. These results suggest that biological treatment may be valuable in reducing membrane fouling while reducing the amount of disinfectants used in pretreatment. (C) 2003 Elsevier Science Ltd. All rights reserved. C1 Montana State Univ, Coll Engn, Ctr Biofilm Engn, Bozeman, MT 59717 USA. MSIN, Pacific NW Natl Labs, Richland, WA 99352 USA. Montana State Univ, Dept Chem Engn, Bozeman, MT 59717 USA. Montana State Univ, Dept Civil Engn, Bozeman, MT 59717 USA. RP Camper, AK (reprint author), Montana State Univ, Coll Engn, Ctr Biofilm Engn, POB 173980, Bozeman, MT 59717 USA. NR 30 TC 26 Z9 26 U1 1 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0043-1354 J9 WATER RES JI Water Res. PD AUG PY 2003 VL 37 IS 14 BP 3367 EP 3378 DI 10.1016/S0043-1354(03)00234-3 PG 12 WC Engineering, Environmental; Environmental Sciences; Water Resources SC Engineering; Environmental Sciences & Ecology; Water Resources GA 701LH UT WOS:000184168700010 PM 12834730 ER PT J AU Kennedy, FE Lidhagen, D Erdemir, A Woodford, JB Kato, T AF Kennedy, FE Lidhagen, D Erdemir, A Woodford, JB Kato, T TI Tribological behavior of hard carbon coatings on steel substrates SO WEAR LA English DT Article; Proceedings Paper CT 14th International Conference on Wear of Materials CY MAR 30-APR 03, 2003 CL WASHINGTON, D.C. DE tribologgicl; hard carbon coatings; steel substrates ID FILMS; FRICTION; WEAR AB In this work the tribological behavior of hard carbon films on steel substrates has been studied under moderately high contact stress conditions. Diamond-like carbon (DLC) coatings of 1 mum thickness were deposited by a plasma-enhanced chemical vapor deposition (PECVD) process on hardened substrates made from 4140 alloy steel. The coated flat specimens were tested in an oscillatory pin-on-disk configuration in contact with either uncoated or carbon-coated hardened steel balls. Peak Hertzian contact pressures ranged from about 300 to 500 MPa and mean sliding velocity was 50 mm/s. In some tests, the specimens were lubricated with 10W-30 motor oil. It was found that wear of the carbon coatings was approximately linearly proportional to contact force. For unlubricated tests, wear rates of the coated specimens were about 200 times less than rates of wear of uncoated steel specimens for the same contact force. The contacting steel ball (uncoated) showed even greater wear reduction (more than 3 orders of magnitude) when tested against coated substrates. Friction coefficients were four to five times lower for coated specimens. Coating the ball as well as the flat resulted in a further reduction (about 50%) in wear of both ball and flat. Friction and wear reduction brought about by carbon coating in lubricated tests was less than for unlubricated specimens. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Dartmouth Coll, Thayer Sch Engn, Hanover, NH 03755 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki, Japan. RP Kennedy, FE (reprint author), Dartmouth Coll, Thayer Sch Engn, Hanover, NH 03755 USA. NR 12 TC 23 Z9 23 U1 1 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD AUG-SEP PY 2003 VL 255 BP 854 EP 858 DI 10.1016/S0043-1648(03)00223-0 PN 2 PG 5 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 733YB UT WOS:000186027300010 ER PT J AU Ziomek-Moroz, M Miller, A Hawk, J Cadien, K Li, DY AF Ziomek-Moroz, M Miller, A Hawk, J Cadien, K Li, DY TI An overview of corrosion-wear interaction for planarizing metallic thin films SO WEAR LA English DT Article; Proceedings Paper CT 14th International Conference on Wear of Materials CY MAR 30-APR 03, 2003 CL WASHINGTON, D.C. DE chemical-mechanical planarization; corrosion-wear interaction; metallic thin films ID COPPER AB Corrosion-wear interactions play a very crucial role in developing many technological processes. One of them is chemical-mechanical planarization (CMP) of metallic thin films for manufacturing semiconductor devices such as computer chips. In this paper, we present research approaches undertaken in developing CMP for different metallic thin films, such as tungsten and copper in aqueous media. Mechanisms of material removal during CMP are presented. The role of corrosion, wear, and their synergistic effect are explained. The importance of constructing corrosion-wear maps for these complicated tribo-corrosion-metallic thin film systems is addressed. The application of corrosion-wear maps in developing reliable CMP slurries and processes is discussed. (C) 2003 Published by Elsevier Science B.V. C1 US DOE, Albany Res Ctr, Albany, OR 97321 USA. Intel Corp, Hillsboro, OR 97124 USA. Univ Alberta, Dept Chem & Mat Engn, Edmonton, AB T6G 2G6, Canada. RP Ziomek-Moroz, M (reprint author), US DOE, Albany Res Ctr, 1450 Queen Ave SW, Albany, OR 97321 USA. OI Cadien, Kenneth/0000-0001-8192-283X NR 16 TC 20 Z9 25 U1 0 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD AUG-SEP PY 2003 VL 255 BP 869 EP 874 DI 10.1016/S0043-1648(03)00225-4 PN 2 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 733YB UT WOS:000186027300012 ER PT J AU Shi, B Ajayi, OO Fenske, G Erdemir, A Liang, H AF Shi, B Ajayi, OO Fenske, G Erdemir, A Liang, H TI Tribological performance of some alternative bearing materials for artificial joints SO WEAR LA English DT Article; Proceedings Paper CT 14th International Conference on Wear of Materials CY MAR 30-APR 03, 2003 CL WASHINGTON, D.C. DE diamond-like carbon; friction and wear; artificial joints ID OSTEOARTHRITIS AB In current artificial joints consisting of metal or ceramic and polyethylene (ultrahigh molecular weight polyethylene, UHMWPE) bearing surfaces, the wear debris of polyethylene is the main cause for shortening implant's life. In order to enhance the durability of human artificial joints, alternative bearing surfaces may be needed. In the present study, the tribological performance of several candidate implant materials, including the diamond-like carbon (DLC) thin film coating on stainless steel were investigated. A pin-on-flat contact configuration in reciprocating sliding was used for preliminary materials evaluation and friction and wear testing. Test pairs were lubricated with bovine blood serum. The DLC coating sliding against uncoated stainless steel showed the lowest friction coefficient and very little, if any, wear. Wear mechanisms in tests of ceramics and steel pairs were primarily abrasive. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Univ Alaska Fairbanks, Dept Engn Mech, Fairbanks, AK 99775 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Shi, B (reprint author), Univ Alaska Fairbanks, Dept Engn Mech, 756160 Fairbanks, Fairbanks, AK 99775 USA. NR 11 TC 31 Z9 33 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD AUG-SEP PY 2003 VL 255 BP 1015 EP 1021 DI 10.1016/S0043-1648(03)00276-X PN 2 PG 7 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 733YB UT WOS:000186027300029 ER PT J AU Covert, RJ Ott, RD Ku, DN AF Covert, RJ Ott, RD Ku, DN TI Friction characteristics of a potential articular cartilage biomaterial SO WEAR LA English DT Article; Proceedings Paper CT 14th International Conference on Wear of Materials CY MAR 30-APR 03, 2003 CL WASHINGTON, D.C. DE friction; cartilage; poly(vinyl-alcohol); biomaterials ID KNEE; JOINTS; LUBRICATION; WALKING AB Many biomaterials are being developed to repair or replace articular cartilage. One of these materials, a poly(vinyl-alcohol) cryogel (PVA-c) may exhibit the mechanical properties required to withstand the harsh environment of diarthrodial joints. To better understand how PVA-c friction is affected by different variables employed in bench top testing to simulate joint conditions, a six-factor, two-level fractional-factorial experiment was developed. Factors included temperature, lubricant, material stiffness, load, sliding speed, and surface roughness. Static and dynamic friction were found to depend significantly on material stiffness and roughness, increasing as material stiffness and roughness increased. Dynamic friction was also inversely proportional to sliding speed. Overall static and dynamic friction for all variables was 0.285 +/- 0.091 and 0.143 +/- 0.066 (average +/- S.D.), respectively. Material deformation and other factors may have contributed to the higher than expected friction levels. Frictional behavior of this PVA-c against stainless steel does not follow Amonton's friction law, nor does it follow friction models based on repulsion and adsorption theories. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Georgia Inst Technol, GWW Sch Mech Engn, Atlanta, GA 30332 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. SaluMedica LLC, Atlanta, GA USA. RP Ku, DN (reprint author), Georgia Inst Technol, GWW Sch Mech Engn, 315 Ferst Dr, Atlanta, GA 30332 USA. NR 21 TC 53 Z9 58 U1 5 U2 15 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD AUG-SEP PY 2003 VL 255 BP 1064 EP 1068 DI 10.1016/S0043-1648(03)00113-3 PN 2 PG 5 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 733YB UT WOS:000186027300037 ER PT J AU Blau, PJ Meyer, HM AF Blau, PJ Meyer, HM TI Characteristics of wear particles produced during friction tests of conventional and unconventional disc brake materials SO WEAR LA English DT Article; Proceedings Paper CT 14th International Conference on Wear of Materials CY MAR 30-APR 03, 2003 CL WASHINGTON, D.C. DE brakes; friction materials; carbon-ceramic composites; cast iron; intermetallic alloys; wear debris AB Recent attention to the improvement of line-haul truck brake effectiveness, to compensate for lowered aerodynamic drag and to increase road safety, has prompted the US Department of Energy to support several projects aimed at the development of lightweight, high-performance friction materials. Using a specially designed, sub-scale disc brake testing system, a series of experiments was conducted to study the friction, wear, and frictional heating characteristics of both conventional and unconventional candidate disc brake materials. The selected sliding speed (11.0 m/s) was comparable to that experienced by a commercial disc brake surface on a truck travelling 60 miles/h (96.6 km/h). Material combinations included a commercial friction material on a gray cast iron disc, a commercial friction material on an aluminum metal matrix composite disc, a commercial friction material on a cast iron aluminide (Fe3Al) alloy disc, and a carbon/silicon carbide material pad on a disc of similar composition. An adhesive extraction method was used to remove the loose wear particles from the surfaces of the test discs. The characteristics of brake material wear particles differed significantly between the four sliding material combinations studied and are correlated with both surface roughness changes and wear modes. (C) 2003 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Blau, PJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 6 TC 47 Z9 48 U1 0 U2 20 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD AUG-SEP PY 2003 VL 255 BP 1261 EP 1269 DI 10.1016/S0043-1648(03)00111-X PN 2 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 733YB UT WOS:000186027300059 ER PT J AU Gross, RL Liu, XH Suits, AG AF Gross, RL Liu, XH Suits, AG TI O(P-3) versus O(D-1) reaction dynamics with n-pentane: a crossed-beam imaging study SO CHEMICAL PHYSICS LETTERS LA English DT Article ID H-ABSTRACTION DYNAMICS; SATURATED-HYDROCARBONS; MOLECULAR-BEAM; CHEMICAL-DYNAMICS; ATOMS AB We present crossed-beam scattering results for reaction of ground state O(P-3) and electronically excited O(D-1) with n-pentane at a collision energy of 13 kcal/mol. The results were obtained using velocity map imaging with 157 nm single-photon ionization of the products. Using this probe, the only reaction channel observed was that producing the hydrocarbon radical and OH. The results show dramatically contrasting dynamics, with backward-sideways scattering dominating the ground state triplet reaction and isotropic/forward scattering for the singlet reaction. (C) 2003 Published by Elsevier B.V. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. RP Suits, AG (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 18 TC 11 Z9 11 U1 2 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JUL 31 PY 2003 VL 376 IS 5-6 BP 710 EP 716 DI 10.1016/S0009-2614(03)01063-7 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 708KL UT WOS:000184565900026 ER PT J AU Bragg, AE Wester, R Davis, AV Kammrath, A Neumark, DM AF Bragg, AE Wester, R Davis, AV Kammrath, A Neumark, DM TI Excited-state detachment dynamics and rotational coherences of C-2(-) via time-resolved photoelectron imaging SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ANGULAR-DISTRIBUTIONS; MOLECULAR ALIGNMENT; PHILLIPS SYSTEM; SWAN SYSTEM; C2 MOLECULE; SPECTROSCOPY; PHOTODETACHMENT; ELECTRONS; CONSTANTS; CLUSTERS AB Time-resolved photoelectron imaging (TRPEI) is used to investigate the effect of time-evolving alignment on the photoelectron angular distribution (PAD) from anion photo detachment. The B <-- X 0(0)(0) transition in C-2(-) is pumped with a ferritosecond laser pulse at 541 nm and probed by femtosecond photodetachment at 264 nm. The pump pulse produces rotational coherences in the upper state that exhibit partial and full revivals, as evidenced by modulation of the PAD anisotropy moments. From these, one can extract the excited state rotational constant of C, and information regarding the molecular frame PAD. (C) 2003 Elsevier B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Neumark, DM (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Neumark, Daniel/B-9551-2009; Wester, Roland/J-6293-2012 OI Neumark, Daniel/0000-0002-3762-9473; Wester, Roland/0000-0001-7935-6066 NR 35 TC 28 Z9 28 U1 0 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JUL 31 PY 2003 VL 376 IS 5-6 BP 767 EP 775 DI 10.1016/S0009-2614(03)01060-1 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 708KL UT WOS:000184565900035 ER PT J AU Hoard, JW Tonkyn, RG AF Hoard, JW Tonkyn, RG TI Two-stage plasma-catalysis for diesel NOx emission control SO JOURNAL OF ADVANCED OXIDATION TECHNOLOGIES LA English DT Article ID NONTHERMAL PLASMA; REDUCTION; REMOVAL AB Plasma discharges in diesel simulated exhaust gas oxidize NO primarily to NO2, while forming aldehydes and other partial-oxidation products from hydrocarbons. Appropriate catalysts can react NOx and aldehydes in the presence of oxygen, producing nitrogen. Suitable catalysts include sodium and barium forms of zeolite-Y, and for higher temperatures, high surface area gamma-alumina. Combinations of catalysts can be more effective that the individual ones, especially considering temperature transients which occur during vehicle operation. An oxidation catalyst is required following the NOx catalysts, to remove remaining hydrocarbon, aldehydes, and HCN species. A cascaded system consisting of multiple plasma-catalyst stages, can achieve higher NOx conversion and/or more efficient electrical power utilization than a single plasma-catalyst system. Best effort laboratory evaluations on simulated exhaust have achieved 90% NOx conversion. Vehicle tests have yet to show such promising results. C1 Ford Res Lab, Dearborn, MI 48121 USA. Pacific NW Natl Lab, Richland, WA USA. RP Ford Res Lab, MD 3179SRL,POB 2053, Dearborn, MI 48121 USA. EM Jhoard@ford.com; rg.Tonkyn@pnl.gov NR 39 TC 8 Z9 8 U1 1 U2 3 PU SYCAMORE GLOBAL PUBLICATIONS LLC PI TERRE HAUTE PA 6815 E MANOR DR, TERRE HAUTE, IN 47802 USA SN 1203-8407 J9 J ADV OXID TECHNOL JI J. Adv. Oxid. Technol. PD JUL 31 PY 2003 VL 6 IS 2 BP 158 EP 165 PG 8 WC Chemistry, Physical SC Chemistry GA 706BB UT WOS:000184430800005 ER PT J AU Zaveri, RA Berkowitz, CM Kleinman, LI Springston, SR Doskey, PV Lonneman, WA Spicer, CW AF Zaveri, RA Berkowitz, CM Kleinman, LI Springston, SR Doskey, PV Lonneman, WA Spicer, CW TI Ozone production efficiency and NOx depletion in an urban plume: Interpretation of field observations and implications for evaluating O-3-NOx-VOC sensitivity SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article DE air pollution; Lagrangian modeling; aircraft measurements ID POWER-PLANT PLUMES; SOUTHEASTERN UNITED-STATES; BOUNDARY-LAYER; CONTROL STRATEGIES; SOUTHERN OXIDANTS; RURAL SITE; JULY 18; NASHVILLE; HYDROCARBONS; EMISSIONS AB Ozone production efficiency ( OPE) can be defined as the number of ozone (O-3) molecules photochemically produced by a molecule of NOx (NO + NO2) before it is lost from the NOx-O-3 cycle. Here we consider observational and modeling techniques to evaluate various operational definitions of OPEs using aircraft and surface measurements taken as part of the 1999 Southern Oxidant Study field campaign in Nashville, Tennessee. A key tool in our analysis is a Lagrangian box model, which is used to quantitatively describe the effects of emissions, dilution, dry deposition, and photochemistry in an urban air parcel as it was advected downwind. After evaluating the model using the observed downwind concentrations of several key species, we show that the modeled NOx oxidation and O-3 production rates as well as the associated instantaneous and cumulative OPEs depend on the time of day and the photochemical age of the air parcel. The observation-based OPEs are found to be consistent with the modeled values with the expected biases. A model sensitivity study suggests that downwind O-3 concentrations in the Nashville plume are more sensitive to NOx emissions than anthropogenic VOC emissions. Because the OPE exhibits a nonlinear dependence on emissions and meteorological effects, it would be difficult to rely only on observations to map out the nonlinear response of O-3 to a wide span of NOx and VOC emission changes. Properly constrained and well-evaluated models using a variety of observations are therefore necessary to reliably predict O-3-NOx-VOC sensitivity for designing effective O3 control strategies. C1 Pacific NW Natl Lab, Atmospher Sci & Global Change Div, Richland, WA 99352 USA. Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. US EPA, Natl Exposure Res Lab, Senior Environm Employment Program, Res Triangle Pk, NC 27711 USA. Battelle Mem Inst, Atmospher Sci & Appl Technol Dept, Columbus, OH 43201 USA. RP Berkowitz, CM (reprint author), Pacific NW Natl Lab, Atmospher Sci & Global Change Div, Battelle Blvd,MSIN K9-30,POB 999, Richland, WA 99352 USA. EM rahul.zaveri@pnl.gov; carl.berkowitz@pnl.gov; kleinman@bnl.gov; srs@bnl.gov; pvdoskey@anl.gov; lonneman.bill@epamail.epa.gov; spicerc@battelle.org OI Zaveri, Rahul/0000-0001-9874-8807 NR 51 TC 36 Z9 37 U1 5 U2 26 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUL 31 PY 2003 VL 108 IS D19 AR 4436 DI 10.1029/2002JD003144 PG 23 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 710WZ UT WOS:000184707000006 ER PT J AU Camaioni, DM Dupuis, M Bentley, J AF Camaioni, DM Dupuis, M Bentley, J TI Theoretical characterization of oxoanion, XOmn-, solvation SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID POLARIZABLE CONTINUUM MODEL; DENSITY-FUNCTIONAL THEORIES; REACTION FIELD-THEORY; ELECTRON-TRANSFER REACTIONS; MST-SCRF CALCULATIONS; AQUEOUS-SOLUTIONS; ATOMIC CHARGES; RATE CONSTANTS; CAVITY SIZE; REDUCTION POTENTIALS AB We describe a new cavity definition protocol that yields accurate solvation energies and electrode potentials for selected oxoanions, XOmn-, including some for which other cavity protocols do not perform well enough. In this new definition scheme with cavities made of interlocked atomic spheres, the radii are given by simple empirically based expressions involving effective atomic charges of the solute atoms that fit the solute molecular electrostatic potential and a bond length-dependent factor to account for atomic size and hybridization. The scheme shows substantial qualitative differences from other previously proposed schemes, for example, by assigning a large radius to the central atom of the oxoanions. This difference is put on a firm theoretical basis in the case of NO3- through an analysis of the molecular electrostatic potential of the nitrate ion and an analysis of its interaction with a "solvent" water molecule. Despite a large positive partial charge assigned to nitrogen in the nitrate ion, the water solvent molecule continues to act as an H-bond donor in the region of the central N atom as a result of the electrostatic potential of the anion, although the water-nitrate interaction in that region is weaker than near the terminal O atoms. From these results, we surmise that the solvent molecules remain further away from the nitrogen atom, a finding that is consistent with the large radius assigned by the new scheme for nitrogen. The same qualitative feature holds true for all of the oxoanions considered here. C1 Pacific NW Natl Lab, Div Chem Sci, Richland, WA 99352 USA. Univ Notre Dame, Radiat Lab, Notre Dame, IN 46556 USA. RP Camaioni, DM (reprint author), Pacific NW Natl Lab, Div Chem Sci, POB 999, Richland, WA 99352 USA. EM donald.camaioni@pnl.gov; michel.dupuis@pnl.gov NR 88 TC 31 Z9 31 U1 0 U2 5 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 JUL 31 PY 2003 VL 107 IS 30 BP 5778 EP 5788 DI 10.1021/jp0343537 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 704TC UT WOS:000184355300017 ER PT J AU Laskin, J Futrell, JH AF Laskin, J Futrell, JH TI Entropy is the major driving force for fragmentation of proteins and protein-ligand complexes in the gas phase SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID INFRARED RADIATIVE DISSOCIATION; INTERMOLECULAR INTERACTIONS; OLIGOSACCHARIDE COMPLEXES; BLACKBODY RADIATION; MASS-SPECTROMETRY; ACTIVATION; KINETICS; ENERGIES; ANIONS; IONS AB This paper presents a critical analysis of Arrhenius parameters for gas-phase fragmentation of proteins and protein-ligand complexes reported in the literature. We demonstrate that there is a surprisingly strong correlation between the Arrhenius activation energy (E.) and the preexponential factor (A). This correlation becomes extremely important for reactions characterized by very high or very low values of A. This correlation is a direct consequence of the relative change in the spacing between vibrational levels of the reactant and the transition state for reaction. Converting the Arrhenius activation energy into the threshold energy for the reaction using Tolman's theorem reveals the true magnitude of the correlation between molecular complexity and stability. Tolman's correction factor (DeltaE(corr),) increases linearly with log(A) from 3 kcal/mol for log(A) = 16.2 to 36.4 kcal/mol for log(A) = 39.2. Threshold energies extracted from the Arrhenius activation parameters for 56 different reactions are the same within the experimental error bars, while the preexponential factors differ by many orders of magnitude. This indicates that activation entropy is the major driving force for dissociation of proteins and protein-ligand complexes in the gas phase. C1 Pacific NW Natl Lab, Fund Sci Div, Richland, WA 99352 USA. RP Laskin, J (reprint author), Pacific NW Natl Lab, Fund Sci Div, POB 999,K8-88, Richland, WA 99352 USA. RI Laskin, Julia/H-9974-2012 OI Laskin, Julia/0000-0002-4533-9644 NR 17 TC 20 Z9 20 U1 0 U2 8 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 JUL 31 PY 2003 VL 107 IS 30 BP 5836 EP 5839 DI 10.1021/jp0345093 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 704TC UT WOS:000184355300024 ER PT J AU Wishart, JF Neta, P AF Wishart, JF Neta, P TI Spectrum and reactivity of the solvated electron in the ionic liquid methyltributylammonium bis(trifluoromethylsulfonyl)imide SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID PICOSECOND PULSE-RADIOLYSIS; REACTION-KINETICS; ULTRAVIOLET-ABSORPTION; CYCLOHEXANE SOLUTIONS; SOLVATOCHROMIC DYES; MOLECULAR MOBILITY; BULK POLYMERS; RADICAL-IONS; MOLTEN-SALTS; NILE-RED AB Fast pulse radiolysis transient absorption experiments were conducted on the ionic liquid methyltributylammonium bis(trifluoromethylsulfonyl)imide (R4NNTf2). The solvated electron was observed to have a very broad absorption band peaking around 1410 nm (epsilon = 2.2 x 10(4) L mol(-1) cm(-1)) and a radiolytic yield (G) of 0.7 x 10(-7) mol J(-1). Dry electron capture by aromatic solutes, such as benzophenone and pyrene, is very efficient in R4NNTf2. Reactions of the solvated electron with the same compounds are diffusion limited, with rate constants of only k approximate to (1-2) x 10(8) L mol(-1) s(-1) due to the high viscosity of the ionic liquid. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Natl Inst Stand & Technol, Phys & Chem Properties Div, Gaithersburg, MD 20899 USA. RP Wishart, JF (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Wishart, James/L-6303-2013 OI Wishart, James/0000-0002-0488-7636 NR 61 TC 123 Z9 126 U1 1 U2 30 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JUL 31 PY 2003 VL 107 IS 30 BP 7261 EP 7267 DI 10.1021/jp027792z PG 7 WC Chemistry, Physical SC Chemistry GA 704TU UT WOS:000184357100006 ER PT J AU Holroyd, RA Wishart, JF Nishikawa, M Itoh, K AF Holroyd, RA Wishart, JF Nishikawa, M Itoh, K TI Reactions of charged species in supercritical xenon as studied by pulse radiolysis SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SELF-TRAPPED EXCITON; RARE-GAS CRYSTALS; NON-POLAR LIQUIDS; TRANSIENT ABSORPTION; ELECTRON-ATTACHMENT; EXCESS ELECTRON; CARBON-DIOXIDE; ARGON; LUMINESCENCE; MOBILITY AB The results of an initial study of the pulse radiolysis of supercritical xenon are reported. In pure xenon, transients are formed that absorb broadly throughout the visible. These transients are assigned to excimer species, Xe-2*, on the basis of lifetime and kinetic data. The formation of excimers by electron-ion recombination was time-resolved by pulse-probe measurements. The excimers can be quenched by adding small amounts of ethane, which then facilitates detection of other transients by absorption spectroscopy. The added ethane also accelerates the thermalization of electrons and allows measurements of fast reaction rates of thermal electrons. Electron attachment to hexafluorobenzene occurs near the maximum rate at high pressures in xenon-ethane mixtures. The C6F6- anion formed absorbs with a maximum at 500 nm and disappears by second-order kinetics. The mobility of this anion, as measured by conductivity, indicates sizable clusters of solvent around the ion at all pressures, which are of maximum size near critical density. The rate of electron transfer from C6F6- to benzoquinone exceeds 1 x 10(11) m(-1) s(-1) at most pressures. The rate maximizes near 62 bar at 21.4 degreesC. A maximum at this pressure is predicted by diffusion. The maximum is related to the increase in cluster size around the anion, which occurs at this pressure. C1 Kanagawa Inst Technol, Fac Engn, Atsugi 2430292, Japan. Univ Tokyo, Dept Pure & Appl Sci, Tokyo 1538902, Japan. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Holroyd, RA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Wishart, James/L-6303-2013 OI Wishart, James/0000-0002-0488-7636 NR 36 TC 11 Z9 11 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JUL 31 PY 2003 VL 107 IS 30 BP 7281 EP 7287 DI 10.1021/jp0300142 PG 7 WC Chemistry, Physical SC Chemistry GA 704TU UT WOS:000184357100009 ER PT J AU Zheng, YJ Case, MA Wishart, JF McLendon, GL AF Zheng, YJ Case, MA Wishart, JF McLendon, GL TI Do main chain hydrogen bonds create dominant electron transfer pathways? An investigation in designed proteins SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID STAPHYLOCOCCAL NUCLEASE; TUNNELING PATHWAYS; BUNDLE PROTEIN; TRANSFER RATES; DEPENDENCE; INTERFACE; PACKING AB We have investigated the contribution of main chain hydrogen bond (H-bond) pathways to the tunneling matrix elements which control electron transfer (ET) rates across an alpha-helical protein matrix. The paradigm system for these investigations is a metal ion-assembled parallel three-helix bundle protein that contains a ruthenium(II) tris(bipyridyl) electron donor and a ruthenium(III) pentammine electron acceptor separated by a direct metal to metal distance of ca. 19 Angstrom, requiring tunneling through 15 Angstrom of alpha-helical peptide. The putative ET pathway was modulated by a synthetic strategy in which specific main chain amide moieties along an alpha-helix were replaced by ester linkages that cannot form equivalent H-bonds. A simple pathway analysis implies a role for such H-bonds in facilitating electron transfer. Within the accuracy of the computational predictions, specific H-bonded pathway models do not predict the differences in the measured ET rates between the parent construct and the different H-bond deletion variants. C1 Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP McLendon, GL (reprint author), Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. RI Wishart, James/L-6303-2013 OI Wishart, James/0000-0002-0488-7636 NR 42 TC 24 Z9 24 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JUL 31 PY 2003 VL 107 IS 30 BP 7288 EP 7292 DI 10.1021/jp027092u PG 5 WC Chemistry, Physical SC Chemistry GA 704TU UT WOS:000184357100010 ER PT J AU Dimitrijevic, NM Saponjic, ZV Bartels, DM Thurnauer, MC Tiede, DM Rajh, T AF Dimitrijevic, NM Saponjic, ZV Bartels, DM Thurnauer, MC Tiede, DM Rajh, T TI Revealing the nature of trapping sites in nanocrystalline titanium dioxide by selective surface modification SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID INTERFACIAL ELECTRON-TRANSFER; PULSE-RADIOLYSIS; AQUEOUS-SOLUTION; TIO2 COLLOIDS; SEMICONDUCTOR PHOTOCATALYSIS; ENERGY-CONVERSION; CHARGE SEPARATION; REDOX REACTIONS; NANOPARTICLES; REDUCTION AB Excess electrons in nanocrystalline TiO2 were studied in bare and dopairtine-capped TiO2 nanoparticles by electron-beam pulse radiolysis. Reaction of hydrated electrons with dopamine-capped TiO2 nanoparticles was found to be at the diffusion-controlled limit, k = 1 x 10(11) M-1 s(-1), while the reaction with 1-hydroxy-1-methylethyl radicals, (CH3)(2)(C) over dot OH, was 2 orders of magnitude slower, k = 4 x 10(8) M-1 s(-1). The reactions result in injection of electrons into the conduction band of TiO2 nanoparticles. Optical absorption spectra of injected excess electrons in dopamine-capped nanoparticles display monotonic featureless wavelength dependence up to 1800 nm. In contrast, bare particles have shown two preferential optical transitions with energies in the visible region (lambda(max) = 670 nm and lambda(max) = 900 nm). Flat band potential of dopamine-capped TiO2 nanoparticles was shifted by 100 mV to more negative values. The strong coupling of dopamine to surface Ti atoms was also found to improve the separation of photogenerated charges. This was demonstrated by the enhanced efficiency of photogenerated electrons in reducing silver cations to metallic silver in systems linked via a dopamine bridge, compared to the same systems linked through carboxyl groups. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Rajh, T (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 58 TC 71 Z9 71 U1 6 U2 33 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JUL 31 PY 2003 VL 107 IS 30 BP 7368 EP 7375 DI 10.1021/jp034064i PG 8 WC Chemistry, Physical SC Chemistry GA 704TU UT WOS:000184357100023 ER PT J AU Fisk, Z AF Fisk, Z TI Condensed-matter physics - Singular behaviour SO NATURE LA English DT Editorial Material ID SUPERCONDUCTIVITY C1 Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Fisk, Z (reprint author), Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. NR 6 TC 1 Z9 1 U1 0 U2 3 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUL 31 PY 2003 VL 424 IS 6948 BP 504 EP 505 DI 10.1038/424504a PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 706LG UT WOS:000184454700027 PM 12891341 ER PT J AU Reeves, WH Skryabin, DV Biancalana, F Knight, JC Russell, PS Omenetto, FG Efimov, A Taylor, AJ AF Reeves, WH Skryabin, DV Biancalana, F Knight, JC Russell, PS Omenetto, FG Efimov, A Taylor, AJ TI Transformation and control of ultra-short pulses in dispersion-engineered photonic crystal fibres SO NATURE LA English DT Article ID STIMULATED RAMAN-SCATTERING; MODE OPTICAL-FIBER; SUPERCONTINUUM GENERATION; CONTINUUM GENERATION; SOLITONS; PROPAGATION AB Photonic crystal fibres (PCFs) offer greatly enhanced design freedom compared to standard optical fibres. For example, they allow precise control of the chromatic dispersion (CD) profile-the frequency dependence of propagation speed-over a broad wavelength range. This permits studies of nonlinear pulse propagation in previously inaccessible parameter regimes. Here we report on spectral broadening of 100-fs pulses in PCFs with anomalously flat CD profiles. Maps of the spectral and spatio-temporal behaviour as a function of power show that dramatic conversion (to both longer and shorter wavelengths) can occur in remarkably short lengths of fibre, depending on the magnitude and shape of the CD profile. Because the PCFs used are single-mode at all wavelengths, the light always emerges in a fundamental guided mode. Excellent agreement is obtained between the experimental results and numerical solutions of the nonlinear wave equation, indicating that the underlying processes can be reliably modelled. These results show how, through appropriate choice of CD, nonlinearities can be efficiently harnessed to generate laser light at new wavelengths. C1 Univ Bath, Dept Phys, Optoelect Grp, Bath BA2 7AY, Avon, England. Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Knight, JC (reprint author), Univ Bath, Dept Phys, Optoelect Grp, Bath BA2 7AY, Avon, England. RI Biancalana, Fabio/C-2377-2008; Knight, Jonathan/D-3879-2011; Russell, Philip/G-5132-2012; OI Knight, Jonathan/0000-0002-0802-8804; Russell, Philip/0000-0002-8972-2477; Biancalana, Fabio/0000-0002-4093-7688 NR 29 TC 287 Z9 304 U1 2 U2 62 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUL 31 PY 2003 VL 424 IS 6948 BP 511 EP 515 DI 10.1038/nature01798 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 706LG UT WOS:000184454700032 PM 12891348 ER PT J AU Dioumaev, VK Bullock, RM AF Dioumaev, VK Bullock, RM TI A recyclable catalyst that precipitates at the end of the reaction SO NATURE LA English DT Article ID LIQUID/SOLID PHASE-SEPARATION; FLUOROUS CATALYSIS; HOMOGENEOUS CATALYSIS; RECOVERABLE CATALYSTS; GREEN CHEMISTRY; SOLVENTS; COMPLEXES; TEMPERATURE; MOLYBDENUM; ALUMINUM AB Homogeneous catalysts-which exist in the same (usually liquid) phase as reactants and products- are usually more selective than heterogeneous catalysts and far less affected by limitations due to slow transport of reactants and products, but their separation from reaction products can be costly and inefficient. This has stimulated the development of strategies that facilitate the recycling of homogeneous catalysts(1-4). Some of these methods exploit the preference of a catalyst for one of two solvents with thermoregulated miscibility(5,6); others exploit a dramatic decrease in catalyst solubility as one reagent is consumed(7,8) or temperature changed after completion of the reaction(9-14). Here we describe a tungsten catalyst for the solvent-free hydrosilylation of ketones that retains its activity until essentially all of the liquid substrate is converted to liquid products, which we can then simply decant to separate the catalyst that precipitates from the products of the reaction. We attribute the ability of the catalyst to retain its solubility and hence activity until completion of the reaction to the transient formation of liquid clathrate(15,16) that contains a few molecules of the substrate per molecule of the otherwise solid catalyst. Insights into the fundamental processes controlling the formation of this liquid clathrate might help to tailor other catalysts and substrates, so as to develop efficient and solvent-free schemes for reactions of practical interest. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Bullock, RM (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. EM bullock@bnl.gov RI Bullock, R. Morris/L-6802-2016 OI Bullock, R. Morris/0000-0001-6306-4851 NR 28 TC 114 Z9 116 U1 1 U2 29 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUL 31 PY 2003 VL 424 IS 6948 BP 530 EP 532 DI 10.1038/nature01856 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 706LG UT WOS:000184454700036 PM 12891351 ER EF