FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Prakash, J Redey, L Vissers, DR AF Prakash, J. Redey, L. Vissers, D. R. TI Effect of Chemical Additives on the Performance of Na/NiCl(2) Cells SO IONICS LA English DT Article AB The effect of chemical additives on the performance of sodium/nickel chloride cells was investigated in quasi-sealed laboratory research cells. The performance of these cells was measured by galvanostatic and galvanodynamic methods. It was observed that the use of sodium bromide, sulfur, sodium iodide, and a combination of these additives enhance the performance of the Na/NiCl(2) cells by reducing the area-specific impedance of the nickel chloride electrode. Improved morphology by the use of the poreformer further improves the nickel utilization and the electrode impedance. The performance enhancement is attributed to the chemical and morphological modifications of the nickel chloride electrode in the Na/NiCl(2) cells. C1 [Prakash, J.] IIT, Ctr Electrochem Sci & Engn, Chicago, IL 60616 USA. [Prakash, J.] IIT, Dept Chem & Environm Engn, Chicago, IL 60616 USA. [Redey, L.; Vissers, D. R.] Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Prakash, J (reprint author), IIT, Ctr Electrochem Sci & Engn, Chicago, IL 60616 USA. FU Department of Energy [W-31-109-Eng. 38] FX The work described here was carried out at the Chemical Technology Division of the Argonne National Laboratory. The authors are grateful to Dr. K. M. Myles and Mr. C. C. Christianson of the Chemical Technology Division, Argonne National Laboratory, and Dr. Kenneth Heitner of the Office of Transportation Systems, Electric and Hybrid Propulsion Division, U. S. Department of Energy for encouragement and support. This work was supported by the Department of Energy under contract No. W-31-109-Eng. 38. NR 16 TC 4 Z9 4 U1 0 U2 2 PU SPRINGER HEIDELBERG PI HEIDELBERG PA TIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANY SN 0947-7047 J9 IONICS JI Ionics PD MAY PY 2000 VL 6 IS 3-4 BP 210 EP 217 DI 10.1007/BF02374068 PG 8 WC Chemistry, Physical; Electrochemistry; Physics, Condensed Matter SC Chemistry; Electrochemistry; Physics GA V18UA UT WOS:000208028500007 ER PT J AU Mesecar, AD Koshland, DE AF Mesecar, AD Koshland, DE TI Sites of binding and orientation in a four-location model for protein stereospecificity SO IUBMB LIFE LA English DT Article DE chirality; enantiomer specificity; enzyme and protein stereospecificity; four-location model; isocitrate dehydrogenase; three-point attachment ID ISOCITRATE DEHYDROGENASE; PHOSPHORYLATION; ERRORS AB The stereospecificity of the enzyme isocitrate dehydrogenase was examined by steady-state kinetics and x-ray crystallography. The enzyme has the intriguing property that the apoenzyme in the absence of divalent metal showed a selectivity for the inactive l-enantiomer of the substrate isocitrate, whereas the enzyme containing magnesium showed selectivity for the physiologically active d-enantiomer, The hydrogen atom on the C2 carbon that is transferred during the reaction was, in both the d- and l-isocitrate complexes, in an orientation very close to that expected for delivery of a hydride ion to the cosubstrate NADP(+). The beta-carboxylate that is eliminated as a CO2 molecule during the reaction occupied the same site on the protein in both the d- and l-isocitrate complexes, In addition, the C3 carbon was in the same protein site in both the d- and l-enantiomers. Only the fourth group, the OH atom, was in a very different position in the apo enzyme and in the metal-containing complexes. A four-location model is necessary to explain the enantiomeric specificity of IDH in contrast to the conventional three-point attachment model. The thermodynamic and kinetic ramifications of this model are explored. C1 Univ Illinois, Ctr Pharmaceut Biotechnol, Chicago, IL 60607 USA. Univ Illinois, Dept Med Chem & Pharmacognosy, Chicago, IL 60607 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. RP Mesecar, AD (reprint author), Univ Illinois, Ctr Pharmaceut Biotechnol, 900 S Ashland Ave,MC 870, Chicago, IL 60607 USA. OI Mesecar, Andrew/0000-0002-1241-2577 NR 25 TC 16 Z9 16 U1 0 U2 2 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1521-6543 J9 IUBMB LIFE JI IUBMB Life PD MAY PY 2000 VL 49 IS 5 BP 457 EP 466 PG 10 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 331CD UT WOS:000087999000017 PM 10902579 ER PT J AU Foley, JC Rehbein, DK AF Foley, JC Rehbein, DK TI Characterizing aluminum sintering using in-situ NDE SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article AB Considerable attention has been given to the use of nondestructive evaluation techniques to reduce the costs associated with the manufacture of powder-metallurgy components. One such technology that is being development the U.S Department of Energy's Ames Laboratory is all in-situ noncontact technique to characterize sintering. The method consists of a high-temperature electromagnetic acoustic transducer to measure the amplitude and velocity of an ultrasonic tone burst traveling through a sample during sintering. Results from the in-situ noncontact nondestructive evaluation measurements indicate that real-time in-situ monitoring of sintering is attainable. C1 Ames Lab, Ames, IA 50011 USA. RP Foley, JC (reprint author), Ames Lab, Ames, IA 50011 USA. NR 9 TC 6 Z9 6 U1 1 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD MAY PY 2000 VL 52 IS 5 BP 38 EP 39 DI 10.1007/s11837-000-0032-1 PG 2 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 313XY UT WOS:000087026000010 ER PT J AU Herwig, KW Fuhrmann, D Criswell, L Taub, H Hansen, FY Dimeo, R Neumann, DA AF Herwig, KW Fuhrmann, D Criswell, L Taub, H Hansen, FY Dimeo, R Neumann, DA TI Dynamics of intermediate-length alkane films absorbed on graphite SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT Workshop on Dynamics in Confinement CY JAN 26-29, 2000 CL INST LAUE-LANGEVIN, GREOBLE, FRANCE SP Inst Laue Langevin HO INST LAUE-LANGEVIN AB The dynamics of flexible chain molecules near a solid interface is of fundamental interest in polymer science. This paper makes a preliminary report on a quasielastic neutron scattering study of the dynamics of monolayer films of C24H50 adsorbed on graphite. Quasielastic scattering was observed at temperatures as low as similar to 180 K, well below the monolayer melting temperature of 340 K, Preliminary analysis of the data indicates that at 230 K the entire molecule executes a rolling motion about its long axis while the terminal methyl groups exhibit relatively rapid reorientation. C1 Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. NIST, Ctr Neutron Res, Gaithersburg, MD USA. RP Herwig, KW (reprint author), Argonne Natl Lab, IPNS, 9700 S Cass Ave,Bldg 360, Argonne, IL 60439 USA. RI Herwig, Kenneth/F-4787-2011 NR 5 TC 4 Z9 4 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 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAY PY 2000 VL 10 IS P7 BP 157 EP 160 DI 10.1051/jp4:2000731 PG 4 WC Physics, Multidisciplinary SC Physics GA 332UV UT WOS:000088092500032 ER PT J AU Bordallo, HN Herwig, KW Dozier, WD Drake, F AF Bordallo, HN Herwig, KW Dozier, WD Drake, F TI Water dynamics in controlled pore silica glasses SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT Workshop on Dynamics in Confinement CY JAN 26-29, 2000 CL INST LAUE-LANGEVIN, GREOBLE, FRANCE SP Inst Laue Langevin HO INST LAUE-LANGEVIN ID NEUTRON-SCATTERING; SUPERCOOLED WATER; LIQUID WATER; RELAXATION; SIMULATION; MOLECULES AB Water in porous silica glass is a suitable system for investigating the effect of confinement on translational diffusion. These systems are important because of their relevance in catalytic and separation processes. Here quasi-elastic neutron scattering experiments at room temperature on water-filled controlled-pore glasses with radius of 15, 24 and 32 Angstrom, are presented and analyzed using the random-jump diffusion model. Both the average residence time and the mean jump distance increase with decreasing pore radius. C1 Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Fannie Mae, Washington, DC 20016 USA. Exxon Res & Engn Co, Annandale, NJ 08801 USA. RP Bordallo, HN (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, Bldg 360, Argonne, IL 60439 USA. RI Herwig, Kenneth/F-4787-2011; Bordallo, Heloisa/I-6836-2012 OI Bordallo, Heloisa/0000-0003-0750-0553 NR 17 TC 6 Z9 6 U1 0 U2 1 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 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAY PY 2000 VL 10 IS P7 BP 207 EP 210 DI 10.1051/jp4:2000741 PG 4 WC Physics, Multidisciplinary SC Physics GA 332UV UT WOS:000088092500042 ER PT J AU Pais, P Tanga, MJ Salmon, CP Knize, MG AF Pais, P Tanga, MJ Salmon, CP Knize, MG TI Formation of the mutagen IFP in model systems and detection in restaurant meats SO JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY LA English DT Article DE heterocyclic amines; cooked meats; IFP; model systems; food mutagen ID HETEROCYCLIC AROMATIC-AMINES; FOOD-PRODUCTS; UNITED-STATES; COOKED FOOD; CANCER; CREATINE; DONENESS; COLON; RISK AB Mixtures of the free amino acids, creatine and glucose, were dry-heated to model the potential formation of heterocyclic amines in meats. The formation of the mutagenic amine IFP (determined to be 2-amino-(1,6-dimethylfuro[3,2-e]imidazo[4,5-b])pyridine) was investigated by varying heating time, heating temperature, and precursors. With an optimized mixture of glutamine, creatine, and glucose, heated at 200 degrees C for 60 min, 2 mg of IFP was purified for studies to define its structure. Trideuteriomethyl-IFP was made from trideuteriomethylcreatinine in the model system for use in LC-MS detection of IFP in foods. Analysis of well-done meats purchased from restaurants showed about half to contain IFP at levels from 1.4 to 46 ng/g of cooked meat, demonstrating human exposure to this mutagen. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. SRI Int, Menlo Park, CA 94025 USA. RP Knize, MG (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 808, Livermore, CA 94551 USA. FU NCI NIH HHS [CA5586] NR 28 TC 35 Z9 35 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-8561 J9 J AGR FOOD CHEM JI J. Agric. Food Chem. PD MAY PY 2000 VL 48 IS 5 BP 1721 EP 1726 DI 10.1021/jf990601d PG 6 WC Agriculture, Multidisciplinary; Chemistry, Applied; Food Science & Technology SC Agriculture; Chemistry; Food Science & Technology GA 315LV UT WOS:000087116000049 PM 10820085 ER PT J AU De Belie, N Lenehan, JJ Braam, CR Svennerstedt, B Richardson, M Sonck, B AF De Belie, N Lenehan, JJ Braam, CR Svennerstedt, B Richardson, M Sonck, B TI Durability of building materials and components in the agricultural environment, part III: Concrete structures SO JOURNAL OF AGRICULTURAL ENGINEERING RESEARCH LA English DT Review ID FEED ACIDS; SILAGE EFFLUENT; SILICA FUME; PIG HOUSES; FLY-ASH; CEMENT; RESISTANCE; ADDITIONS; ATTACK; FLOORS AB This final part of the literature review gives an overview of the knowledge on durability of concrete structures, concrete being undeniably one of the most frequently used building materials for solid and slatted floors in animal houses and for manure and silage storage structures. Resistance against corrosion caused by lactic and acetic acids is of major importance both for floors and silos. Concrete manure tanks, walls of manure pits in animal houses and the underside of concrete slats and slabs are exposed to biogenic sulphuric acid corrosion. Different demands for producing a high-quality and durable concrete structure are discussed. This includes correct specification of the concrete mix (water/cement ratio, cement content), compaction and curing. The influence of the cement type, pozzolanic additions, aggregate type, polymer additions, application of cement-bound surface layers, impregnation with water repellents or pore blockers and application of coatings, on the corrosion resistance is reviewed. (C) 2000 Silsoe Research Institute. C1 Katholieke Univ Leuven, Dept Agroengn & Econ, Louvain, Belgium. TEAGASC, Grange Res Ctr, Agr & Food Dev Author, Dunsany, Meath, Ireland. Delft Univ Technol, Fac Civil Engn, Concrete Struct Grp, Delft, Netherlands. Swedish Univ Agr Sci, Dept Agr Biosyst & Technol, Alnarp, Sweden. Univ Coll Dublin, Dept Civil Engn, Dublin 2, Ireland. Agr Res Ctr, Dept Mechanisat Labour Bldg Anim Welf & Environm, Ghent, Belgium. RP De Belie, N (reprint author), Katholieke Univ Leuven, Dept Agroengn & Econ, Louvain, Belgium. NR 112 TC 24 Z9 24 U1 3 U2 16 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0021-8634 J9 J AGR ENG RES JI J. Agr. Eng. Res. PD MAY PY 2000 VL 76 IS 1 BP 3 EP 16 DI 10.1006/jaer.1999.0520 PG 14 WC Agricultural Engineering SC Agriculture GA 316FA UT WOS:000087155900002 ER PT J AU Weller, A Frangos, W Seichter, M AF Weller, A Frangos, W Seichter, M TI Three-dimensional inversion of induced polarization data from simulated waste SO JOURNAL OF APPLIED GEOPHYSICS LA English DT Article DE electrical resistivity; geoelectrical prospection; induced polarization; inversion algorithm ID SPECTRAL-INDUCED POLARIZATION AB The Idaho National Laboratory (INEL) Cold Test Pit (CTP) has been carefully constructed to simulate buried hazardous waste sites. An induced polarization (IP) survey of the CTP shows a very strong polarization and a modest resistivity response associated with the simulated waste. A three-dimensional (3-D) inversion algorithm based on the simultaneous iterative reconstruction technique (SIRT) and finite difference forward modelling has been applied to generate a subsurface model of complex resistivity. The lateral extents of the waste zone are well resolved. Limited depth extent is recognized, but the bottom of the waste appears too deep. With a modelling experiment, the intrinsic polarizability of the waste material is determined. Since IP is a technique for detection of diffuse occurrences of metallic material, this method holds promise as a method to distinguish buried waste from conductive soil material. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Tech Univ Clausthal, Inst Geophys, D-38678 Clausthal Zellerfeld, Germany. Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. Tech Univ Carolo Wilhelmina Braunschweig, Inst Meteorol & Geophys, D-38106 Braunschweig, Germany. RP Tech Univ Clausthal, Inst Geophys, Arnold Sommerfeld Str 1, D-38678 Clausthal Zellerfeld, Germany. EM andreas.weller@tu-clausthal.de NR 28 TC 16 Z9 21 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-9851 EI 1879-1859 J9 J APPL GEOPHYS JI J. Appl. Geophys. PD MAY PY 2000 VL 44 IS 2-3 BP 67 EP 83 DI 10.1016/S0926-9851(00)00007-0 PG 17 WC Geosciences, Multidisciplinary; Mining & Mineral Processing SC Geology; Mining & Mineral Processing GA 317GU UT WOS:000087218300002 ER PT J AU Slater, L Binley, AM Daily, W Johnson, R AF Slater, L Binley, AM Daily, W Johnson, R TI Cross-hole electrical imaging of a controlled saline tracer injection SO JOURNAL OF APPLIED GEOPHYSICS LA English DT Article DE resistivity; tomography; solute transport; pixel-breakthroughs ID RESISTIVITY TOMOGRAPHY; RESISTANCE TOMOGRAPHY; INVERSION AB Electrical imaging of tracer tests can provide valuable information on the spatial variability of solute transport processes. This concept was investigated by cross-borehole electrical imaging of a controlled release in an experimental tank. A saline tracer (conductivity 8 X 10(3) ms/m volume 270 1) was injected into a tank facility (dimensions 10 X 10 X 3 m) consisting of alternating sand and clay layers. Injection was from 0.3 m below the surface, at a point where maximum interaction between tank structure and tracer transport was expected. Repeated imaging over a two-week period detected non-uniform tracer transport, partly caused by the sand/clay sequence. Tracer accumulation on two clay layers was observed and density-driven spill of tracer over a clay shelf was imaged. An additional unexpected flow pathway, probably caused by complications during array installation, was identified close to an electrode array. Pore water samples obtained following termination of electrical imaging generally supported the observed electrical response, although discrepancies arose when analysing the response of individual pixels. The pixels that make up the electrical images were interpreted as a large number of breakthrough curves. The shape of the pixel breakthrough-recession curve allowed some quantitative interpretation of solute travel time, as well as a qualitative assessment of spatial variability in advective-dispersive transport characteristics across the image plane. Although surface conduction effects associated with the clay layers complicated interpretation, the plotting of pixel breakthroughs was considered a useful step in the hydrological interpretation of the tracer test. The spatial coverage provided by the high density of pixels is the factor that most encourages the approach. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Missouri, Dept Geosci, Kansas City, MO 64110 USA. Univ Lancaster, Inst Environm & Nat Sci, Lancaster LA1 4YQ, England. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Oregon Grad Inst Sci & Technol, Ctr Groundwater Res, Portland, OR 97291 USA. RP Slater, L (reprint author), Univ Missouri, Dept Geosci, 5100 Rockhill Rd, Kansas City, MO 64110 USA. RI Binley, Andrew/C-2487-2013 OI Binley, Andrew/0000-0002-0938-9070 NR 24 TC 210 Z9 211 U1 6 U2 25 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-9851 J9 J APPL GEOPHYS JI J. Appl. Geophys. PD MAY PY 2000 VL 44 IS 2-3 BP 85 EP 102 DI 10.1016/S0926-9851(00)00002-1 PG 18 WC Geosciences, Multidisciplinary; Mining & Mineral Processing SC Geology; Mining & Mineral Processing GA 317GU UT WOS:000087218300003 ER PT J AU Clothiaux, EE Ackerman, TP Mace, GG Moran, KP Marchand, RT Miller, MA Martner, BE AF Clothiaux, EE Ackerman, TP Mace, GG Moran, KP Marchand, RT Miller, MA Martner, BE TI Objective determination of cloud heights and radar reflectivities using a combination of active remote sensors at the ARM CART sites SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID ATMOSPHERIC RADIATION; MICROPULSE LIDAR; PROFILING RADAR; 94-GHZ RADAR; PROGRAM; SIGNALS AB The U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) Program is deploying sensitive, millimeter-wave cloud radars at its Cloud and Radiation Test Bed (CART) sites in Oklahoma, Alaska, and the tropical western pacific Ocean. The radars complement optical devices, including a Belfort or Vaisala Laser ceilometer and a micropulse lidar, in providing a comprehensive source of information on the vertical distribution of hydrometeors overhead at the sites. An algorithm is described that combines data from these active remote sensors to produce an objective determination of hydrometeor height distributions and estimates of their radar reflectivities, vertical velocities, and Doppler spectral widths, which are optimized for accuracy. These data provide fundamental information for retrieving cloud microphysical properties and assessing the radiative effects of clouds on climate. The algorithm is applied to nine months of data from the CART site in Oklahoma for initial evaluation. Much of the algorithm's calculations deal with merging and optimizing data from the radar's four sequential operating modes, which have differing advantages and limitations, including problems resulting from range sidelobes, range aliasing, and coherent averaging. Two of rile modes use advanced phase-coded pulse compression techniques to yield approximately 10 and 15 dB more sensitivity than is available from the two conventional pulse modes. Comparison of cloud-base heights from the Belfort ceilometer and the micropulse lidar confirms small biases found in earlier studies, but recent information about the ceilometer brings the agreement to within 20-30 m. Merged data of the radar's modes were found to miss approximately 5.9% of the clouds detected by the laser systems. Using data from only the radar's two less-sensitive conventional pulse modes would increase the missed detections to 22%-34%. A significant remaining problem is that the radar's lower-altitude data are often contaminated with echoes from nonhydrometeor targets, such as insects. C1 Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. NOAA, Environm Technol Lab, Boulder, CO USA. Brookhaven Natl Lab, Div Appl Sci, Upton, NY 11973 USA. RP Clothiaux, EE (reprint author), Penn State Univ, Dept Meteorol, 503 Walker Bldg, University Pk, PA 16802 USA. NR 18 TC 293 Z9 298 U1 3 U2 26 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD MAY PY 2000 VL 39 IS 5 BP 645 EP 665 DI 10.1175/1520-0450(2000)039<0645:ODOCHA>2.0.CO;2 PG 21 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 315LY UT WOS:000087116300005 ER PT J AU Bowen, BM AF Bowen, BM TI Near-neutral surface layer turbulence at the boulder atmospheric observatory tower: Evidence of increasing vertical turbulence with height SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article ID CLASSIFICATION SCHEMES; STABILITY AB Wind and turbulence profiles were analyzed during breezy, near-neutral conditions at the Boulder Atmospheric Observatory tower to quantify the effects of an abrupt 20- to 30-m increase in terrain located 3-5 kin west of the tower. Results indicate that regional roughness length z(o) is greatest and local z(o) is smallest in sectors downwind of a long, shallow bluff, suggesting that distant, more complex, upwind terrain enhances horizontal turbulence but has little effect on local wind speed profiles. Turbulence parameter profiles are nearly constant up to 200 in above ground level (AGL), and friction velocity u(*) is neatly constant up to 150-200 m for simple fetch with z(o) equal to 4 cm and near-surface wind speed approximately equal to 7 m s(-1) at 10 In AGL. Horizontal turbulence parameters, however. increase by 50% to nearly 100% at all tower levels downwind of the distant terrain bluff when compared with those with simple fetch. The effect of the bluff on vertical turbulence increases with height. Although the effect on the 10-m standard deviation of vertical wind speed sigma(u) is negligible, the 200-m sigma(u) increases by about 0.5 m s(-1), or about twice the 10-m value. The u(*) also increases by 16% to nearly 100% between the 10- and 200-m heights downwind of the bluff. Primarily because of the enhanced sigma(w) downwind of the bluff, atmospheric dispersion could be underestimated by factors of about 2.5, 2.0, and 1.3 at the 200-, 100-, and 50-m levels, respectively, if the vertical and transverse standard deviations of the wind angle fluctuations are estimated from 10-m values. C1 Univ Calif Lawrence Livermore Natl Lab, Div Atmospher Sci, NARAC, Livermore, CA 94551 USA. RP Bowen, BM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Div Atmospher Sci, NARAC, L-103,POB 808, Livermore, CA 94551 USA. NR 23 TC 4 Z9 5 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD MAY PY 2000 VL 39 IS 5 BP 716 EP 724 DI 10.1175/1520-0450-39.5.716 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 315LY UT WOS:000087116300010 ER PT J AU Xie, JJ Chen, SP AF Xie, JJ Chen, SP TI Generation of Frenkel defects in heavily arsenic doped silicon: A first-principles study SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INITIO PSEUDOPOTENTIAL CALCULATIONS; ELECTRICAL DEACTIVATION; DOPANT DIFFUSION; SI; SYSTEMS; COMPLEX AB The generation of Frenkel defects (a self-interstitial and a vacancy) in heavily As doped Si is investigated theoretically based on first-principles total energy calculations. We find that it is much easier to generate a self-interstitial and a vacancy close to substitutional As atoms than in pure Si, due to the lower energy cost. The As atom binds strongly with the vacancy, but does not bind with Si self-interstitial and other As atoms. We have considered several different reactions such as Si-5--> Si4V+I, AsSi4--> AsSi3V+I, As2Si3--> As2Si2V+I, As3Si2--> As3SiV+I, and As4Si --> As4V+I. The theoretical results are in good agreement with experimental observations. (C) 2000 American Institute of Physics. [S0021-8979(00)04309-7]. 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 18 TC 20 Z9 21 U1 0 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 MAY 1 PY 2000 VL 87 IS 9 BP 4160 EP 4163 DI 10.1063/1.373046 PN 1 PG 4 WC Physics, Applied SC Physics GA 308QJ UT WOS:000086724100017 ER PT J AU Seager, CH Tallant, DR AF Seager, CH Tallant, DR TI The role of activator-activator interactions in reducing in low-voltage-cathodoluminescence efficiency in Eu and Tb doped phosphors SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB High resolution measurements of spectrally resolved cathodoluminescence (CL) decay have been made in several commercial and experimental phosphors doped with Eu and Tb at beam energies ranging from 0.8 to 4 keV. CL emission from the lowest two excited states of both rare-earth activators was compared to the decay of photoluminescence (PL) after pulsed laser excitation. We find that, at long times after the cessation of electron excitation, the CL decay rates are comparable to those measured in PL; at short times, the decay process is considerably faster and has a noticeable dependence on the energy of the electron beam. These beam energy effects are largest for the higher excited states and for phosphors with larger activator concentrations. Measurements of the experimental phosphors over a range of activator fractions from 0.1 to 0.002 show that the beam energy dependence of the steady-state CL efficiency is larger for higher excited states and weakens as the activator concentration is reduced; the latter effect is strongest for Y2SiO5:Tb, but also quite evident in Y2O3:Eu. We suggest that the electron beam dependence of both the decay lifetimes and the steady state CL efficiency may be due to interaction of nearby excited states which occurs as a result of the large energy deposition rate for low energy electrons. This picture for nonradiative quenching of rare-earth emission is an excited state analog of the well-known (ground state-excited state) concentration quenching mechanism. (C) 2000 American Institute of Physics. [S0021-8979(00)02609-8]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Seager, CH (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 4264 EP 4267 DI 10.1063/1.373063 PN 1 PG 4 WC Physics, Applied SC Physics GA 308QJ UT WOS:000086724100034 ER PT J AU Potter, BG Tikare, V Tuttle, BA AF Potter, BG Tikare, V Tuttle, BA TI Monte Carlo simulation of ferroelectric domain structure and applied field response in two dimensions SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID FIRST PRINCIPLES; BATIO3; PEROVSKITES; LATTICE AB A two-dimensional, lattice-Monte Carlo approach, based upon the energy minimization of an ensemble of electric dipoles, was developed to simulate ferroelectric domain behavior. The model utilizes a Hamiltonian for the total energy based upon electrostatic terms involving dipole-dipole interactions, local polarization gradients, and the influence of applied electric fields. The impact of boundary conditions on the domain configurations obtained was also examined. In general, the model exhibits domain structure characteristics consistent with those observed in a tetragonally distorted ferroelectric. The model was also extended to enable the simulation of ferroelectric hysteresis behavior. Simulated hysteresis loops were found to be very similar in appearance to those observed experimentally in actual materials. This qualitative agreement between the simulated hysteresis loop characteristics and real ferroelectric behavior was also confirmed in simulations run over a range of simulation temperatures and applied field frequencies. (C) 2000 American Institute of Physics. [S0021- 8979(00)08509-1]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Potter, BG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 40 Z9 40 U1 2 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 4415 EP 4424 DI 10.1063/1.373086 PN 1 PG 10 WC Physics, Applied SC Physics GA 308QJ UT WOS:000086724100059 ER PT J AU Levine, ZH Kalukin, AR Kuhn, M Frigo, SP McNulty, I Retsch, CC Wang, YX Arp, U Lucatorto, TB Ravel, BD Tarrio, C AF Levine, ZH Kalukin, AR Kuhn, M Frigo, SP McNulty, I Retsch, CC Wang, YX Arp, U Lucatorto, TB Ravel, BD Tarrio, C TI Tomography of integrated circuit interconnect with an electromigration void SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID RECONSTRUCTION AB An integrated circuit interconnect was subject to accelerated-life test conditions to induce an electromigration void. The silicon substrate was removed, leaving only the interconnect test structure encased in silica. We imaged the sample with 1750 eV photons using the 2-ID-B scanning transmission x-ray microscope at the Advanced Photon Source, a third-generation synchrotron facility. Fourteen views through the sample were obtained over a 170 degrees range of angles (with a 40 degrees gap) about a single rotation axis. Two sampled regions were selected for three-dimensional reconstruction: one of the ragged end of a wire depleted by the void, the other of the adjacent interlevel connection (or "via"). We applied two reconstruction techniques: the simultaneous iterative reconstruction technique and a Bayesian reconstruction technique, the generalized Gaussian Markov random field method. The stated uncertainties are total, with one standard deviation, which resolved the sample to 200 +/- 70 and 140 +/- 30 nm, respectively. The tungsten via is distinguished from the aluminum wire by higher absorption. Within the void, the aluminum is entirely depleted from under the tungsten via. The reconstructed data show the applicability of this technique to three-dimensional imaging of buried defects in submicrometer structures relevant to the microelectronics industry. (C) 2000 American Institute of Physics. [S0021-8979(00)00509-0]. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Rensselaer Polytech Inst, Troy, NY 12180 USA. Intel Corp RA1 329, Hillsboro, OR 97124 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. EM zlevine@nist.gov RI Arp, Uwe/C-2854-2009; OI Arp, Uwe/0000-0002-6468-9455 NR 17 TC 22 Z9 22 U1 2 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 MAY 1 PY 2000 VL 87 IS 9 BP 4483 EP 4488 DI 10.1063/1.373095 PN 1 PG 6 WC Physics, Applied SC Physics GA 308QJ UT WOS:000086724100068 ER PT J AU Lewis, LH Kramer, MJ Dennis, KW McCallum, RW AF Lewis, LH Kramer, MJ Dennis, KW McCallum, RW TI Compositional clustering in Nd2Fe14B melt-spun ribbons SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MAGNETS AB Elevated-temperature superconducting quantum interference device magnetometry was employed to investigate the detailed phase constitution of nominally glassy stoichiometric Nd2Fe14B melt-spun ribbons modified with 6 wt % Ti/C and subjected to various degrees of quenching by circumferential wheel speed variations of 40, 35, and 20 m/s. While previous microstructural characterization indicated that these materials were completely amorphous, ac susceptibility and magnetization measurements analyzed within the framework of superparamagnetism indicates that the materials actually contain a concentration of crystalline phase clusters of Nd2Fe14B and alpha-Fe that remained undetected by previous microstructural characterization due to their small size (diameter < 5 nm) and inhomogeneous spatial distribution. The Curie temperatures of the glassy component increase with decreasing wheel speed, while the amount of glass varies in a systematic manner from 78 to 91 wt %. The remaining phases in the quenched product are Nd2Fe14B and alpha-Fe. Analysis of the distribution and size of the alpha-Fe clusters provides insight into the nucleation and growth process that ultimately produces the crystallized microstructure associated with high energy-product melt-spun Nd2Fe14B-based magnets. (C) 2000 American Institute of Physics. [S0021-8979(00)29408-5]. C1 Brookhaven Natl Lab, Dept Appl Sci, Div Mat & Chem Sci, Upton, NY 11973 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Lewis, LH (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Div Mat & Chem Sci, Upton, NY 11973 USA. NR 10 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 4735 EP 4737 DI 10.1063/1.373142 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200022 ER PT J AU Merkulova, GY Margulies, L Dennis, KW McCallum, RW AF Merkulova, GY Margulies, L Dennis, KW McCallum, RW TI The temperature dependence of coercivity in nanocrystalline Nd-Fe-B-(TiC) magnets SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc AB TiC additions to Nd2Fe14B have been shown to enhance the control of microstructure and greatly modify the solidification behavior of the alloy. The temperature dependence of the coercivity, H-ci, of the Nd2Fe14B+xTiC(0 < x < 6 at. %) is important for both technical applications and a comprehensive understanding of the coercivity mechanism. In addition, by studying the onset of coercivity as a function of the annealing temperature of amorphous ribbons the activation energy for crystallization may be determined. Amorphous melt-spun ribbons with x=0, 2, 3, and 6 were annealed isothermally in an Ar atmosphere at temperatures near, above and below the crystallization temperature. The activation energies E-a were determined by fitting the dependence of the coercivity as a function of annealing time and temperature to the Arrenius' equation and found to be 18-25 kcal. The coercivity distribution functions of micro volumes of magnets were created using demagnetization and reversible magnetization curves that allowed the correlation of the coercive force with nanostructure. Maximum H-ci of up to 15 kOe (3 at. % TiC) is achieved for an average grain size of 20-40 nm. The temperature dependencies of coercivity of stoichiometric Nd2Fe14B ribbons without and with additions TiC have similar character in temperature range (250-400 K) for all samples. The coercivities for nanocrystalline Nd2Fe14B magnets with TiC are more than for stoichiometric material. (C) 2000 American Institute of Physics. [S0021-8979(00)63408-4]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. RP McCallum, RW (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 4 TC 2 Z9 2 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 4738 EP 4740 DI 10.1063/1.373143 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200023 ER PT J AU Crew, DC Lewis, LH Welch, DO Pourarian, F AF Crew, DC Lewis, LH Welch, DO Pourarian, F TI The effect of temperature on the magnetization reversal mechanism in sintered PrFeB SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MAGNETS AB To understand the effects of nucleation fields and intergranular dipolar interactions on the magnetization reversal mechanism, recoil curves from the major hysteresis loop have been measured on a sample of sintered PrFeB as a function of temperature from 150 to 300 K. At room temperature the reversible magnetization behavior indicates a reversal mechanism of nucleation of domain walls whose motion after nucleation is resisted by dipolar fields. As the temperature is reduced, the coercivity, and hence the nucleation field, is observed to increase while the dipolar fields, dependent on microstructure and saturation magnetization, remain approximately constant. These temperature-dependent changes in the relative magnitudes of the dipolar field and nucleation field cause the reversible magnetization behavior to change from domain wall motion to rotation. This change in behavior is attributed to the supposition that at temperatures where the nucleation field exceeds the dipolar field, once nucleated, domain walls are swept out of the material. (C) 2000 American Institute of Physics. [S0021-8979(00)29508-X]. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Carnegie Mellon Res Inst, Pittsburgh, PA 15230 USA. RP Crew, DC (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. EM dcrew@bnl.gov NR 7 TC 6 Z9 6 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 MAY 1 PY 2000 VL 87 IS 9 BP 4744 EP 4746 DI 10.1063/1.373145 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200025 ER PT J AU Girt, E Altounian, Z AF Girt, E Altounian, Z TI Model for predicting atomic substitutions in intermetallic compounds SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID PREFERENTIAL SITE OCCUPATION; NEUTRON-DIFFRACTION; MAGNETIC-PROPERTIES; FE; OCCUPANCY; ALLOYS; TI AB A thermodynamic model was developed for calculating the probabilities of atomic substitutions in different sites in intermetallic compounds. The model considers three contributions: chemical, elastic and structural, in calculating the changes that occur in the enthalpy due to the atomic substitutions at different sites in intermetallic compounds. The model was tested for over forty rare-earth containing compounds such as Nd-2(Fe,X)(17)(C), Nd-2(Fe,X)(14)B, R(Fe,X)(12), R(Al,X)(12), Nd-3(Fe,X)(29) and Er(Ni,X)(5) where X is the substituent atom. Comparison of the model calculations with results obtained from neutron diffraction show that the model precisely determines the sites preferentially occupied by the X atoms. (C) 2000 American Institute of Physics. [S0021-8979(00)89408-6]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. McGill Univ, Ctr Phys Mat, Dept Phys, Montreal, PQ H3A 2T8, Canada. RP Girt, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Altounian, Zaven/A-2073-2008 NR 19 TC 8 Z9 8 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 4747 EP 4749 DI 10.1063/1.373146 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200026 ER PT J AU Clatterbuck, DM Garcia, VJ Johnson, MJ Jiles, DC AF Clatterbuck, DM Garcia, VJ Johnson, MJ Jiles, DC TI An extended model of the Barkhausen effect based on the ABBM model SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID STRESS AB The Barkhausen model of Alessandro [J. Appl. Phys. 68, 2901 (1990)] has been extended to nonstationary domain wall dynamics. The assumptions of the original model limit, its use to situations where the differential permeability, and time derivative of applied field are constant. The later model of Jiles assumes that the Barkhausen activity in a given time interval is proportional to the rate of change of irreversible magnetization which can be calculated from hysteresis models. The extended model presented here incorporates ideas from both of these. It assumes that the pinning field and domain wall velocity behave according to the Alessandro model, but allows the rate of change of the magnetic flux to vary around a moving average which is determined by the shape of the hysteresis curve and the applied magnetic field wave form. As a result, the new model allows for changes in permeability with applied field and can also reproduce the frequency response of experimental Barkhausen signals. (C) 2000 American Institute of Physics. [S0021-8979(00)77908-4]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Ctr Nondestruct Evaluat, Ames, IA 50011 USA. RP Clatterbuck, DM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Jiles, David/H-9548-2012 NR 6 TC 7 Z9 8 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 4771 EP 4773 DI 10.1063/1.373154 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200034 ER PT J AU Crew, DC Lewis, LH AF Crew, DC Lewis, LH TI The effect of pinning and nucleation field distributions on reversible magnetization behavior SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc AB A model has been developed to examine the effect that different distributions of pinning and nucleation fields have upon the reversible magnetization behavior. The model allows each grain to be in one of three states, saturated in the positive and negative directions or containing a domain wall. The nucleation and pinning field distributions determine the rate of change of the number of grains in the three states with field. The results indicate that reversible magnetization curves display a well-defined minimum where the domain wall pinning fields exceed the reverse domain nucleation fields. Where the domain wall nucleation fields exceed the domain wall pinning fields no minimum is seen. The exact shape of the reversible magnetization curve and the position of the minimum are indicative of the dynamics of the reversal process. This model is able to reproduce the form of reversible magnetization curves measured previously in a sintered isotropic NdFeB based magnet and a Sm-2(Co, Fe, Cu, Zr)(17) type magnet. (C) 2000 American Institute of Physics. [S0021-8979(00)15208-9]. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Crew, DC (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 5 TC 19 Z9 19 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 4783 EP 4785 DI 10.1063/1.373158 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200038 ER PT J AU Morais, J Fecher, GH Denecke, R Hussain, Z Fadley, CS AF Morais, J Fecher, GH Denecke, R Hussain, Z Fadley, CS TI Magnetic dichroism in core-level photoemission from Gd(0001) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID CIRCULAR-DICHROISM; PHOTOELECTRON DIFFRACTION; SPIN AB This work reports on magnetic dichroism in photoemission from the Gd 4l(l=s,p,d,f ) core level of in-plane magnetized Gd films excited with linearly, circularly, and unpolarized light. Thin Gd films of about 100 ML thickness were evaporated onto a W(110) substrate at room temperature, and subsequently annealed to 700 K to form an ordered layer exhibiting a (0001) surface. The dichroism measurements were performed by physically rotating the sample azimuth so as to change the direction of the magnetization axis relative to the incident light. The magnetic dichroism asymmetries were obtained by calculating the normalized difference between spectra obtained with the two mutually orthogonal orientations of the magnetization. Strong asymmetries were observed, even if exciting the spectra by means of unpolarized light. The experimental results are compared to three-step photoemission cluster calculations based on a relativistic full potential algorithm respecting magnetic exchange. (C) 2000 American Institute of Physics. [S0021-8979(00)89808-4]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Morais, J (reprint author), LNLS Brazilian Synchrotron Light Source, CP 6192, BR-13083097 Campinas, SP, Brazil. RI Fecher, Gerhard/H-2470-2011; Morais, Jonder/E-5022-2013 OI Morais, Jonder/0000-0002-4143-1208 NR 7 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 4900 EP 4902 DI 10.1063/1.373196 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200077 ER PT J AU Mao, M Cerjan, C Law, B Grabner, F Vaidya, S AF Mao, M Cerjan, C Law, B Grabner, F Vaidya, S TI Influence of base pressure on FeMn exchange biased spin-valve films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc AB The influence of base pressure, P-b, on physical properties of FeMn exchange biased spin-valve films was studied by varying P-b over two decades from 3x10(-8) to 7x10(-6) Torr. Giant magnetoresistive value shows a slight increase with increasing P-b until a large decrease occurs at P-b> 3.3x10(-6) Torr. Exchange bias field and blocking temperature remain constant in the base pressure range between 3x10(-8) and 5x10(-7) Torr before a large reduction appears. Our results indicate an upper limit for base pressure, (u)P(b)approximate to 5x10(-7) Torr, above which significant spin-valve performance modification and deterioration in the crystallographic texture begin as a result of the contamination both at the ferromagnetic/antiferromagnetic interface and in the bulk of FeMn layer. (C) 2000 American Institute of Physics. [S0021-8979(00)36008-X]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Mao, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 6 TC 6 Z9 9 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 4933 EP 4935 DI 10.1063/1.373207 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200088 ER PT J AU Welp, U Berger, A Miller, DJ Vlasko-Vlasov, VK Gray, KE Mitchell, JF AF Welp, U Berger, A Miller, DJ Vlasko-Vlasov, VK Gray, KE Mitchell, JF TI Magneto-optical imaging of the first order spin-flop transition in the layered manganite La1.4Sr1.6Mn2O7 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID INTERPLANE TUNNELING MAGNETORESISTANCE; CRYSTAL AB The spin-flop transition in the antiferromagnetic layered manganite La1.4Sr1.6Mn2O7 was studied using magnetization measurements and a high-resolution magneto-optical imaging technique. We report the direct observation of the formation of ferromagnetic domains appearing at the first order spin-flop transition. The magnetization process proceeds through nucleation of polarized domains at crystal defect sites and not through the expansion of polarized domains due to domain wall motion. A small magnetic hysteresis is caused by the difference between the mechanisms of nucleation and annihilation of domains in the mixed state. These results establish a direct link between the magnetic structure on the atomic scale as seen in neutron scattering and the macroscopic properties of the sample as seen in magnetization and conductivity measurements. (C) 2000 American Institute of Physics. [S0021-8979(00)54008-0]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Welp, U (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Gao, Jinlong/C-1489-2010; Berger, Andreas/D-3706-2015 OI Berger, Andreas/0000-0001-5865-6609 NR 17 TC 8 Z9 8 U1 2 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5043 EP 5045 DI 10.1063/1.373242 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200124 ER PT J AU te Velthuis, SGE Berger, A Felcher, GP Hill, BK Dahlberg, ED AF te Velthuis, SGE Berger, A Felcher, GP Hill, BK Dahlberg, ED TI Training effects and the microscopic magnetic structure of exchange biased Co/CoO bilayers SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID ANISOTROPY; FILMS; MODEL; INTERFACES AB Exchange bias of a partially oxidized thin film of ferromagnetic Co was studied by magnetization measurements and polarized neutron reflectivity (PNR). The magnetization curve shows strong effects of training with cycling of the magnetic field. Reflectivity measurements with the field parallel to the cooling field showed the onset of spin-dependent diffuse scattering-off the specular reflection-after a training cycle. Such scattering, of the Yoneda type, is due to misaligned Co domains possibly close to the Co/CoO interface. Subjecting the field cooled Co/CoO pair to a field perpendicular to the cooling field causes a rotation of the magnetization. The PNR measurements confirmed earlier susceptibility studies by indicating that the rotation of the magnetization is reversible in fields up to 400 Oe. The rotation of the magnetization of Co is uniform across the film thickness. (C) 2000 American Institute of Physics. [S0021-8979(00)59008-2]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Minnesota, Dept Phys, Minneapolis, MN 55455 USA. RP te Velthuis, SGE (reprint author), Argonne Natl Lab, Div Mat Sci, Bldg 223,9700 S Cass Ave, Argonne, IL 60439 USA. RI te Velthuis, Suzanne/I-6735-2013; Berger, Andreas/D-3706-2015 OI te Velthuis, Suzanne/0000-0002-1023-8384; Berger, Andreas/0000-0001-5865-6609 NR 13 TC 67 Z9 67 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5046 EP 5048 DI 10.1063/1.373243 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200125 ER PT J AU Zein, NE Antropov, VP Harmon, BN AF Zein, NE Antropov, VP Harmon, BN TI Screened exact exchange functional calculations of the spin-wave dispersion in transition metals SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID LINEAR-RESPONSE CALCULATIONS; BAND-STRUCTURE CALCULATIONS; LATTICE-DYNAMICS; ASA METHOD; APPROXIMATION; SUSCEPTIBILITY; NICKEL AB The screened "exact" nonlocal exchange approach is applied to the calculation of magnetic susceptibility of transition metals, particularly to the calculation of spin-wave dispersion. We discuss the choice of an appropriate approach and aspects of linear muffin-tin orbital-atomic sphere approximation (ASA) calculations, in particular calculation of the Green function in the three-center approximation. We calculated transverse spin-wave frequencies in Fe with the local density approximation and with the nonlocal functional using both the "frozen" magnon method and calculation of bound state energies (corresponding to spin-wave excitations). (C) 2000 American Institute of Physics. [S0021-8979(00)64508-5]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Russian Res Ctr Kurchatov Inst, Moscow 123182, Russia. RP Antropov, VP (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 23 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5079 EP 5081 DI 10.1063/1.373254 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200136 ER PT J AU Koo, H Luu, TV Gomez, RD Metlushko, VV AF Koo, H Luu, TV Gomez, RD Metlushko, VV TI Slow magnetization dynamics of small permalloy islands SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID PARTICLES; CONFIGURATIONS; MICROSCOPY; ELEMENTS; ARRAYS AB The conditions that lead to specific domain configurations and the associated switching characteristics of small permalloy islands were studied by using magnetic force microscopy. By measuring a large number of particles, it was established that islands that have nonzero remanent moments (nonsolenoidal) exist in one of three distinct configurations, namely: (a) true single domain, (b) quasisingle domain with edge closure patterns, and (c) multidomain with nonuniform internal magnetization. The configuration depended upon the island width as well as the aspect ratio. Islands that are 310 nm wide or less are true single domain particles at low aspect ratios (similar to 1.87) and higher, while islands wider than 500 nm always exhibited edge closure domains even for very large aspect ratios. In the range between 310 and 500 nm, the onset of single domain behavior was a function of the aspect ratio and thickness. Our studies involving in situ applied field similarly revealed the mechanisms of the reversal processes for each of the configurations, which correlated quite well with the values of the switching fields. (C) 2000 American Institute of Physics. [S0021-8979(00)37308-X]. C1 Lab Phys Sci, College Pk, MD 20740 USA. Univ Maryland, Dept Elect & Comp Engn, College Pk, MD 20742 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Gomez, RD (reprint author), Lab Phys Sci, 8050 Greenmead Dr, College Pk, MD 20740 USA. OI Koo, Hyun Cheol/0000-0001-5044-1355 NR 7 TC 17 Z9 17 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5114 EP 5116 DI 10.1063/1.373266 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200148 ER PT J AU Osborn, R Goremychkin, EA Rainford, BD Sashin, IL Murani, AP AF Osborn, R Goremychkin, EA Rainford, BD Sashin, IL Murani, AP TI Anomalous magnetic response of Ce1-xLaxAl3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID 2-STATE SYSTEM; COMPOUND CEAL3; DYNAMICS AB We have been conducting a systematic investigation of the effect of chemical pressure on the ground state properties of the heavy fermion system Ce1-xLaxAl3. We observe the development of an inelastic magnetic response below a characteristic temperature T* (2.2 K at x=0.2,2.1 K at x=0.5) from the high-temperature quasielastic response. This inelastic response is also extremely sensitive to applied pressure. Our observations are consistent with the predictions of the anisotropic Kondo model. (C) 2000 American Institute of Physics. [S0021-8979(00)89908-9]. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Southampton, Dept Phys, Southampton SO17 1BJ, Hants, England. Joint Inst Nucl Res, Frank Lab Neutron Phys, Dubna 141980, Russia. Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. RP Osborn, R (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Osborn, Raymond/E-8676-2011 OI Osborn, Raymond/0000-0001-9565-3140 NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5131 EP 5133 DI 10.1063/1.373272 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200154 ER PT J AU Mikulina, O Kamarad, J Lacerda, A Syshchenko, O Fujita, T Prokes, K Sechovsky, V Nakotte, H Beyerman, W Menovsky, AA AF Mikulina, O Kamarad, J Lacerda, A Syshchenko, O Fujita, T Prokes, K Sechovsky, V Nakotte, H Beyerman, W Menovsky, AA TI Pressure effects on antiferromagnetism in UNiAl SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MAGNETOELASTIC PHENOMENA; INTERMETALLIC COMPOUNDS; MAGNETORESISTANCE; UNIGA AB The temperature dependencies of the electrical resistivity rho for current along and perpendicular to the c axis were measured on single crystalline UNiAl under various hydrostatic pressures. The rho(T) curves at ambient pressure exhibit a Cr anomaly around the Neel temperature T-N. Application of pressure causes a reduction of T-N value. Linear extrapolation of low-pressure T-N vs p data yields an estimate of a critical pressure for antiferromagnetism p(c)approximate to 10 GPa. Measurements above 1 GPa, however, reveal a collapse of the antiferromagnetic (AF) ordering already below 3 GPa, although AF correlations seem to affect resistivity behavior rho(T) in pressures up to 8 GPa. A sudden change of the rho(T) curve character for i perpendicular to c and T < T-N indicates a pressure-induced change of magnetic ordering or fluctuations within the basal plane. The results are discussed in terms of the instability of the itinerant 5f-electron antiferromagnetism in UNiAl. (C) 2000 American Institute of Physics. [S0021-8979(00)65108-3]. C1 Charles Univ, Dept Elect Struct, Prague 12116 2, Czech Republic. Acad Sci Czech Republ, Inst Phys, Prague 162253 6, Czech Republic. Univ Calif Los Alamos Natl Lab, Pulse Field Facil, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Hiroshima Univ, Dept Quantum Matter, Higashihiroshima 7398526, Japan. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. Univ Amsterdam, Van der Waals Zeeman Inst, NL-1018 XE Amsterdam, Netherlands. RP Prokes, K (reprint author), Charles Univ, Dept Elect Struct, Prague 12116 2, Czech Republic. RI Kamarad, Jiri/G-5880-2014; Sechovsky, Vladimir/A-5256-2008 OI Kamarad, Jiri/0000-0003-3502-9930; Sechovsky, Vladimir/0000-0003-1298-2120 NR 10 TC 7 Z9 7 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5152 EP 5154 DI 10.1063/1.373279 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200161 ER PT J AU Butler, WH Zhang, XG MacLaren, JM AF Butler, WH Zhang, XG MacLaren, JM TI Solution to the Boltzmann equation for layered systems for current perpendicular to the planes SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID GIANT MAGNETORESISTANCE; MAGNETIC MULTILAYERS; TRANSPORT AB Present theories of giant magnetoresistance (GMR) for current perpendicular to the planes (CPP) are based on an extremely restricted solution to the Boltzmann equation that assumes a single free electron band structure for all layers and all spin channels. Within this model only the scattering rate changes from one layer to the next. This model leads to the remarkable result that the resistance of a layered material is simply the sum of the resistances of each layer. We present a solution to the Boltzmann equation for CPP for the case in which the electronic structure can be different for different layers. The problem of matching boundary conditions between layers is much more complicated than in the current in the planes (CIP) geometry because it is necessary to include the scattering-in term of the Boltzmann equation even for the case of isotropic scattering. This term couples different values of the momentum parallel to the planes. When the electronic structure is different in different layers there is an interface resistance even in the absence of intermixing of the layers. The size of this interface resistance is affected by the electronic structure, scattering rates, and thicknesses of nearby layers. For Co-Cu, the calculated interface resistance and its spin asymmetry is comparable to that measured at low temperature in sputtered samples. (C) 2000 American Institute of Physics. [S0021-8979(00)71908-6]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Tulane Univ, New Orleans, LA 70018 USA. RP Butler, WH (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 17 TC 16 Z9 16 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5173 EP 5175 DI 10.1063/1.373285 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200168 ER PT J AU Zhang, XG Butler, WH AF Zhang, XG Butler, WH TI A simple treatment of the "scattering-in" term of the Boltzmann equation for multilayers SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MAGNETORESISTANCE AB We present a simple approximation for treating anisotropic scattering within the semiclassical Boltzmann equation for current in plane geometry in magnetic multilayers. This approximation can be used to qualitatively account for the forward scattering that is neglected in the lifetime approximation, and requires only one additional parameter. For the case of a bulk material its effect is a simple renormalization of the scattering rate. The simplicity of this term has allowed quick and simple solution to the Boltzmann equation for magnetic multilayers using realistic band structures. When we use the band structures for Cu\Co multilayers obtained from first-principles calculations, we find an increase in the resistance of the multilayer, compared to the solution without the scattering-in term, due to the higher scattering rates needed to fit the same bulk conductivities. The giant-magnetoresistance ratio is also changed when the vertex corrections are included. (C) 2000 American Institute of Physics. [S0021-8979(00)72008-1]. C1 Oak Ridge Natl Lab, Computat Phys & Engn Div, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Zhang, XG (reprint author), Oak Ridge Natl Lab, Computat Phys & Engn Div, POB 2008, Oak Ridge, TN 37831 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5176 EP 5178 DI 10.1063/1.373286 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200169 ER PT J AU You, CY Bader, SD AF You, CY Bader, SD TI Voltage controlled spintronic devices for logic applications SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID TUNNEL-JUNCTIONS; INTERLAYER; MAGNETORESISTANCE AB We consider logic device concepts based on our previously proposed spintronics device element whose magnetization orientation is controlled by application of a bias voltage instead of a magnetic field. The basic building block is the voltage-controlled rotation (VCR) element that consists of a four-layer structure-two ferromagnetic layers separated by both nanometer-thick insulator and metallic spacer layers. The interlayer exchange coupling between the two ferromagnetic layers oscillates as a function of applied voltage. We illustrate transistorlike concepts and reprogrammable logic gates based on VCR elements. (C) 2000 American Institute of Physics. [S0021-8979(00)32508-7]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP You, CY (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI You, Chun-Yeol/B-1734-2010; Bader, Samuel/A-2995-2013 OI You, Chun-Yeol/0000-0001-9549-8611; NR 11 TC 18 Z9 18 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5215 EP 5217 DI 10.1063/1.373299 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200182 ER PT J AU Girt, E Guillot, M Swainson, IP Krishnan, KM Altounian, Z Thomas, G AF Girt, E Guillot, M Swainson, IP Krishnan, KM Altounian, Z Thomas, G TI Structural and magnetic properties of Nd2Fe17-delta Ga delta (delta <= 2) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID NEUTRON-DIFFRACTION; SOLID-SOLUTIONS; SI AB Magnetization measurements of Nd2Fe17-deltaGadelta (delta=0-2) show that the saturation magnetization, M-s, decreases with an increase in Ga content from 40.4 mu(B)/f.u. for Nd2Fe17 to 36.1 mu(B)/f.u. for Nd2Fe15Ga2 at 4.2 K. Neutron diffraction data at 25 K show that the magnetic moment of Fe depends on its crystallographic site and decreases in the order Fe(6c)> Fe(18f)greater than or equal to Fe(18h)greater than or equal to Fe(9d). The magnetic moments of Fe(9d), Fe(18f), and Fe(18h) are found to be practically independent of the Ga content. However, the magnetic moment of Fe(6c) decreases from 2.81(9) mu(B) in Nd2Fe17 to 2.14(9) mu(B) in Nd2Fe15Ga2. The decrease of the Fe(6c) moment clearly reduces the exchange interaction between Fe(6c)-Fe(6c) dumbbell pairs which explains the decrease in the anomalous thermal expansion with an increase in Ga concentration. The reduced Fe(6c)-Fe(6c) exchange interaction may also play an important role in increasing the Curie temperature, T-C, with Ga content; T-C increases from 327 K in Nd2Fe17 to 535 K in Nd2Fe15Ga2. (C) 2000 American Institute of Physics. [S0021-8979(00)22008-2]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. CNRS, MPI, Lab Champs Magnet Intenses, F-38042 Grenoble, France. Steacie Inst Mol Sci, NRC, Neutron Program Mat Res, Chalk River, ON K0J 1P0, Canada. McGill Univ, Ctr Phys Mat, Dept Phys, Montreal, PQ H3A 2T8, Canada. RP Girt, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Altounian, Zaven/A-2073-2008 NR 10 TC 8 Z9 9 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5323 EP 5325 DI 10.1063/1.373335 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200218 ER PT J AU Felcher, GP AF Felcher, GP TI Neutron reflectometry as a tool to study magnetism (invited) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID FE/CR(001) SUPERLATTICES; FIELD PENETRATION; X-RAY; DEPTH; MULTILAYERS; REFLECTION; FILMS; DIFFRACTION; PHASE; MAGNETORESISTANCE AB Polarized-neutron specular reflectometry (PNR) was developed in the 1980's as a means of measuring magnetic depth profiles in flat films. Starting from simple profiles, and gradually solving structures of greater complexity, PNR has been used to observe or clarify a variety of magnetic phenomena. It has been used to measure the absolute magnetization of films of thickness not exceeding a few atomic planes, the penetration of magnetic fields in micron-thick superconductors, and the detailed magnetic coupling across nonmagnetic spacers in multilayers and superlattices. The development of new scattering techniques promises to enable the characterization of lateral magnetic structures. Retaining the depth sensitivity of specular reflectivity, off-specular reflectivity may be brought to resolve in-plane structures over nanometer to micron length scales. (C) 2000 American Institute of Physics. [S0021-8979(00)15508-2]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Felcher, GP (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 41 TC 18 Z9 18 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5431 EP 5436 DI 10.1063/1.373365 PN 2 PG 6 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200248 ER PT J AU Robinson, RA AF Robinson, RA TI Prospects for performing neutron scattering in intense pulsed magnetic fields (invited) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID METAMAGNETIC TRANSITION; R2T17 COMPOUNDS; EXCITATIONS; DIFFRACTION; MN-12-ACETATE; FLUCTUATIONS; ANISOTROPY; YBA2CU3O7; CLUSTERS; SYSTEM AB Present dc split-pair superconducting magnets designed for neutron scattering studies can reach fields up to 14.5 T. Prospects for achieving pulsed magnetic fields up to 30 T in conjunction with spallation neutron sources are reviewed, along with a number of scientific questions that can be addressed with such a capability. (C) 2000 American Institute of Physics. [S0021-8979(00)15608-7]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Robinson, RA (reprint author), Univ Calif Los Alamos Natl Lab, LANSCE-12, Mail Stop H805, Los Alamos, NM 87545 USA. NR 51 TC 3 Z9 3 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5437 EP 5442 DI 10.1063/1.373366 PN 2 PG 6 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200249 ER PT J AU Schumann, FO Tobin, JG AF Schumann, FO Tobin, JG TI Magnetic properties of Fe-based alloys SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID CORE-LEVEL PHOTOEMISSION; REORIENTATION TRANSITION; ULTRATHIN FILMS; BINARY-ALLOYS; X-RAY; DICHROISM; MOMENTS; INSTABILITY; CU(100); CU(001) AB The magnetic properties of fcc FexNi1-x and FexCo1-x alloys grown on Cu(100) were investigated in an element-specific fashion. The technique employed was linear dichroism in photoemission, which by varying the chirality can also determine the magnetization axis. We observed a different behavior for the two alloys at Fe concentrations above 60%. At this concentration the FexNi1-x alloy shows a strong reduction of the Fe dichroism associated with the invar instability. This is in contrast to the FexCo1-x alloy, where the Fe dichroism stays essentially constant across the concentration. Despite these differences both systems show a change of the easy axis at roughly the same electron count. For small Fe concentrations the easy axis is in-plane along the [011] direction. This changes into the [001] direction at Fe63Ni37, which is at 0.7 excess electrons per atom when compared with Fe. This is different to the bulk, where a change occurs at Fe25Ni75. We find the easy axis change for FexCo1-x to occur at 49% Fe. This would be equivalent to 0.5 excess electrons when compared with Fe. (C) 2000 American Institute of Physics. [S0021-8979(00)90208-1]. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94551 USA. RP Schumann, FO (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94551 USA. RI Schumann, Frank /K-9364-2014; Tobin, James/O-6953-2015 NR 20 TC 3 Z9 3 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5460 EP 5462 DI 10.1063/1.373372 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200255 ER PT J AU Parker, GJ Cerjan, C AF Parker, GJ Cerjan, C TI Micromagnetic simulations of submicron cobalt dots SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc AB Numerical simulations of submicron Co extruded elliptical dots were performed to illustrate the relative importance of different physical parameters on the switching behavior in the easy direction. Shape, size, magnetic moment magnitude, and the magnitude and distribution of the crystalline anisotropicity were varied. The simulation represents magnetostatic, exchange, and crystalline anisotropicity fields on a structured mesh using finite difference techniques. The smooth boundary of the dots is accurately represented by use of the embedded curve boundary method. Agreement with experimental hysteresis measurements of submicron dot arrays is obtained when an appropriate angular distribution of the grain anisotropicity axes is invoked. (C) 2000 American Institute of Physics. [S0021-8979(00)78508-2]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Parker, GJ (reprint author), Seagate Res, 2403 Sidney St, Pittsburgh, PA 15203 USA. NR 4 TC 16 Z9 17 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5514 EP 5516 DI 10.1063/1.373389 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200272 ER PT J AU Gammel, PL Lopez, D Bishop, DJ Eskildsen, MR Andersen, NH Mortensen, K Fisher, IR Cheon, KO Canfield, PC AF Gammel, PL Lopez, D Bishop, DJ Eskildsen, MR Andersen, NH Mortensen, K Fisher, IR Cheon, KO Canfield, PC TI Interwoven magnetic and flux line structures in single crystal (Tm,Er)Ni2B2C (invited) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID WEAK FERROMAGNETISM; SUPERCONDUCTIVITY; ERNI2B2C; STATE; TMNI2B2C; COEXISTENCE; TRANSITIONS; LUNI2B2C; LATTICE; ORDER AB We review studies of the interactions between magnetic order and the flux line lattice (FLL) in the (RE)Ni2B2C intermetallic borocarbides for (RE) = Tm and Er using small angle neutron scattering (SANS) and magneto-transport. For (RE) = Tm the magnetic order and the FLL assume a common symmetry, sharing a phase transition at similar to 2 kOe, despite an order of magnitude difference in periodicity. For (RE) = Er, the penetration depth lambda and the coherence length xi, both of which are derived from the FLL form factor, are modified near T-N = 6 K by a theoretically predicted weakly divergent pairbreaking. Finally, below 2.3 K, (RE) = Er shows a coexistence of weak ferromagnetism and superconductivity. This state reveals a highly disordered FLL and a striking increase in the critical current, both arising from the strong ferromagnetic pairbreaking. (C) 2000 American Institute of Physics. [S0021-8979(00)61908-4]. C1 Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. Riso Natl Lab, DK-4000 Roskilde, Denmark. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RP Gammel, PL (reprint author), Lucent Technol, Bell Labs, 700 Mt Ave, Murray Hill, NJ 07974 USA. RI Mortensen, Kell/A-5066-2009; Eskildsen, Morten/E-7779-2011; Andersen, Niels/A-3872-2012; Canfield, Paul/H-2698-2014 OI Mortensen, Kell/0000-0002-8998-9390; NR 26 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5544 EP 5548 DI 10.1063/1.373399 PN 2 PG 5 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200282 ER PT J AU Lin, YK Miller, DJ Jiang, JS Pearson, J Bader, SD AF Lin, YK Miller, DJ Jiang, JS Pearson, J Bader, SD TI Temperature dependent anomalous Hall effect in La-Ca-Mn-O films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID LA0.67CA0.33MNO3; LA1-XSRXMNO3 AB The colossal magnetoresistance of La1-xCaxMnO3 has been reported in many experiments. We present our study of the anomalous Hall effect in epitaxial La0.67Ca0.33MnO3 thin films. We have measured the temperature dependence of resistivity, magnetization, and anomalous Hall effect coefficients between 300 and 5 K for our samples grown on different substrates. From these studies, the relation between the resistivity and anomalous Hall effect coefficient as well as the temperature dependence of the anomalous Hall effect coefficient are explored. Our results show that the direction of the anomalous Hall effect is reversed below approximately 100 K. This sign reversal is discussed in terms of band structure and the coexistence of hole-like and electron-like conduction. (C) 2000 American Institute of Physics. [S0021-8979(00)33608-8]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Lin, YK (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Bader, Samuel/A-2995-2013 NR 13 TC 1 Z9 1 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5576 EP 5578 DI 10.1063/1.373409 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200292 ER PT J AU Borca, CN Cheng, RH Xu, QL Liou, SH Stadler, S Idzerda, YU Dowben, PA AF Borca, CN Cheng, RH Xu, QL Liou, SH Stadler, S Idzerda, YU Dowben, PA TI Origin of the magnetic moments in La0.65Pb0.35MnO3 epitaxial thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID RAY-ABSORPTION-SPECTROSCOPY; TRANSITION-METAL COMPOUNDS; VALENCE-BAND STRUCTURE; ELECTRONIC-STRUCTURE; COLOSSAL MAGNETORESISTANCE; LA1-XSRXMNO3; LA1-XCAXMNO3; PEROVSKITES; LA(0.65)A(0.35)MNO(3); PHOTOEMISSION AB Crystalline films of La0.65Pb0.35MnO3 grown on (100) LaAlO (3) substrates by rf sputtering have been investigated using magnetic circular dichroism and inverse photoemission spectroscopy. We find evidence for strong hybridization between unoccupied levels associated with Mn 3d and O 2p states. The oxygen atoms "pick-up" a small magnetic moment through hybridization with Mn. (C) 2000 American Institute of Physics. [S0021-8979(00)41908-0]. C1 USN, Res Lab, NSLS, Upton, NY 11973 USA. USN, Res Lab, Mat Phys Branch, Washington, DC 20375 USA. RP Borca, CN (reprint author), Univ Nebraska, Dept Phys & Astron, Lincoln, NE 68588 USA. NR 22 TC 4 Z9 4 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5606 EP 5608 DI 10.1063/1.372465 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200302 ER PT J AU Kowalewski, M Butler, WH Moghadam, N Stocks, GM Schulthess, TC Song, KJ Thompson, JR Arrott, AS Zhu, T Drewes, J Katti, RR McClure, MT Escorcia, O AF Kowalewski, M Butler, WH Moghadam, N Stocks, GM Schulthess, TC Song, KJ Thompson, JR Arrott, AS Zhu, T Drewes, J Katti, RR McClure, MT Escorcia, O TI The effect of Ta on the magnetic thickness of permalloy (Ni81Fe19) films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc AB The effect of Ta and Ta/Cu seed layers, and Ta and Cu cap layers on the effective magnetic thickness of ultrathin permalloy (Ni81Fe19) was investigated for MRAM applications. The films were deposited by Ion Beam Deposition. The magnetic moment of each as-deposited permalloy film was measured using a B-H looper and a SQUID magnetometer. The films were further annealed at either 525 K for 1/2 h or 600 K for 1 h to study the effect of thermally driven interdiffusion on the magnetic moment of the permalloy film. Our theoretical calculations showed that the presence of 12% intermixing at the interface reduces the Ni moments to zero. Experimentally, it was shown that the tantalum rather than the copper interfaces are primarily responsible for the magnetically dead layers. The Ta seed layer interface produces a loss of moment equivalent to a magnetically dead layer of thickness 0.6 +/- 0.2 nm. The Ta metal in the cap layer results in a loss of moment equivalent to a dead layer of thickness 1.0 +/- 0.2 nm. Upon annealing, thermally driven interdiffusion is concluded to have a strong effect on the Ta(seed)/ Ni81Fe19 as-deposited interface, based on the doubling of the magnetically dead layer to 1.2 +/- 0.2 nm. The Ni81Fe19/Ta(cap) as-deposited interface slightly increases its equivalent magnetically dead layer upon annealing to 1.2 +/- 0.2 nm. As-deposited interfaces of Ta(seed)/permalloy and permalloy/Ta(cap) are not chemically equivalent and result in different magnetically dead layers, whereas after annealing to 600 K both interfaces attain comparable intermixing and magnetically dead layers. It was also shown that a half-hour anneal at the lower 525 K annealing temperature, which is closer to the actual processing temperature, results in only slight increase of the magnetically dead layer at both interfaces. (C) 2000 American Institute of Physics. [S0021-8979(00)73808-4]. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Honeywell Inc, Plymouth, MN 55441 USA. Commonwealth Sci Corp, Alexandria, VA 22314 USA. RP Kowalewski, M (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Stocks, George Malcollm/Q-1251-2016 OI Stocks, George Malcollm/0000-0002-9013-260X NR 4 TC 45 Z9 45 U1 2 U2 18 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5732 EP 5734 DI 10.1063/1.372504 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200343 ER PT J AU Schulthess, TC Butler, WH AF Schulthess, TC Butler, WH TI Magnetostatic coupling in spin valves: Revisiting Neel's formula SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MULTILAYERS AB We use a numerical, atomistic approach to calculate the magnetostatic coupling in spin valves. In addition to the numerical treatment, the coupling energy is evaluated analytically and it is shown that Neel's formula is accurate to first order in the ratio of roughness amplitude to grain size. We also generalize the formula so that it can be applied to systems such as Py/Co/Cu/Co/Py spin valves that have complex ferromagnetic layers. (C) 2000 American Institute of Physics. [S0021-8979(00)45208-4]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Schulthess, TC (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 9 TC 15 Z9 15 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5759 EP 5761 DI 10.1063/1.372513 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200352 ER PT J AU Weller, D Baglin, JEE Kellock, AJ Hannibal, KA Toney, MF Kusinski, G Lang, S Folks, L Best, ME Terris, BD AF Weller, D Baglin, JEE Kellock, AJ Hannibal, KA Toney, MF Kusinski, G Lang, S Folks, L Best, ME Terris, BD TI Ion induced magnetization reorientation in Co/Pt multilayers for patterned media SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID IRRADIATION AB Co/Pt multilayer films with perpendicular magnetic anisotropy and large out-of-plane coercivities of 3.9-8.5 kOe have been found to undergo a spin reorientation transition from out-of-plane to in-plane upon irradiation with 700 keV nitrogen ions. X-ray reflectivity experiments show that the multilayer structure gets progressively disrupted with increasing ion dose, providing direct evidence for local atomic displacements at the Co/Pt interfaces. This effectively destroys the magnetic interface anisotropy, which was varied by about a factor of 2, between K-S congruent to 0.4 erg/cm(2) and K-S congruent to 0.85 erg/cm(2) for two particular films. The dose required to initiate spin-reorientation, 6 x 10(14) N+/cm(2) and 1.5 x 10(15) N+/cm(2), respectively, scales with K-S. It is roughly equal to the number of Co interface atoms per unit interface area contributing to K-S. (C) 2000 American Institute of Physics. [S0021-8979(00)67908-2]. C1 IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, NCEM, Berkeley, CA 94720 USA. RP Weller, D (reprint author), IBM Corp, Almaden Res Ctr, 650 Harry Rd, San Jose, CA 95120 USA. RI Folks, Liesl/C-7611-2016 OI Folks, Liesl/0000-0003-0161-957X NR 11 TC 82 Z9 82 U1 1 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5768 EP 5770 DI 10.1063/1.372516 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200355 ER PT J AU Chen, Y Snyder, JE Dennis, KW McCallum, RW Jiles, DC AF Chen, Y Snyder, JE Dennis, KW McCallum, RW Jiles, DC TI Temperature dependence of the magnetomechanical effect in metal-bonded cobalt ferrite composites under torsional strain SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID TORQUE; MAGNETIZATION; RING AB Metal-bonded cobalt ferrite composites are promising candidates for torque sensors and other magnetostrictive sensing and actuating applications. In the present study, the temperature dependence of the magnetomechanical effect in a ring-shape cobalt ferrite composite under torsional strain has been investigated in the temperature range of -37 to 90 degrees C. The changes of external axial magnetic field were measured as a function of applied torque. Magnetomechanical sensitivity of Delta H-ext/Delta tau=65 A N-1 m(-2) was observed with a magnetomechanical hysteresis of Delta tau=+/- 0.62 N m at room temperature (22 degrees C). These were then measured as a function of temperature. Both decreased as the temperature increased throughout the entire range. The magnetomechanical hysteresis became negligible at temperatures higher than 60 degrees C, above which there was a linear change in external magnetic field with applied torque. These temperature dependences are explained by the changes of magnetostriction, anisotropy, spontaneous magnetization, and pinning of domain walls caused by the availability of increased thermal energy. (C) 2000 American Institute of Physics. [S0021- 8979(00)94408-6]. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Chen, Y (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RI Jiles, David/H-9548-2012 NR 16 TC 26 Z9 26 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5798 EP 5800 DI 10.1063/1.372526 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200365 ER PT J AU Oseroff, SB Moreno, NO Pagliuso, PG Rettori, C Huber, DL Gardner, JS Sarrao, JL Thompson, JD Causa, MT Alejandro, G Tovar, M Alascio, BR AF Oseroff, SB Moreno, NO Pagliuso, PG Rettori, C Huber, DL Gardner, JS Sarrao, JL Thompson, JD Causa, MT Alejandro, G Tovar, M Alascio, BR TI Spin dynamics in perovskites, pyrochlores, and layered manganites SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID ESR AB High temperature electron spin resonance (ESR) and magnetic susceptibility (chi) are analyzed for manganites related with colossal magnetoresistance (CMR). The properties of compounds with different crystalline structures: three-dimensional (3D) perovskites, pyrochlore, and La1.2Sr1.8Mn2O7, a two-dimensional layer, are compared. In the paramagnetic regime, and outside the critical regions associated with phase transitions, the temperature dependence of the ESR linewidth presents a universal behavior dominated by the variations of chi(T), Delta H-pp(T)=[C/T chi(T)]Delta H-pp(infinity). The high temperature limit of the linewidth, Delta H-pp(infinity), is related to the parameters of the Hamiltonian describing the interactions of the spin system. The role played by magnetic anisotropy, isotropic superexchange, and double exchange is revealed and discussed in the analysis of the experimental data. In CMR and non-CMR pyrochlores, Delta H-pp(infinity)proportional to omega(p)(2)/J where J is proportional to the Curie-Weiss temperature, including the hybridization mechanism producing CMR. Instead, Delta H-pp(infinity) of CMR perovskites seems not to be affected by the double-exchange interaction. In contrast with the 3D perovskites, the ESR linewidth and resonance field of La1.2Sr1.8Mn2O7, a bilayer compound, although isotropic at high temperatures, becomes anisotropic for T-c=125 K < T < T(p)approximate to 450 K. (C) 2000 American Institute of Physics. [S0021-8979(00)42308-X]. C1 San Diego State Univ, San Diego, CA 92182 USA. UNICAMP, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. Univ Wisconsin, Madison, WI 53706 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Ctr Atom Bariloche, RA-8400 San Carlos de Bariloche, Rio Negro, Argentina. Comis Nacl Energia Atom, Inst Balseiro, RA-8400 San Carlos de Bariloche, Rio Negro, Argentina. Univ Nacl Cuyo, RA-8400 San Carlos de Bariloche, Rio Negro, Argentina. RP Oseroff, SB (reprint author), San Diego State Univ, San Diego, CA 92182 USA. RI Rettori, Carlos/C-3966-2012; Pagliuso, Pascoal/C-9169-2012; Moreno, Nelson/H-1708-2012; Gardner, Jason/A-1532-2013; Inst. of Physics, Gleb Wataghin/A-9780-2017 OI Rettori, Carlos/0000-0001-6692-7915; Moreno, Nelson/0000-0002-1672-4340; NR 10 TC 9 Z9 9 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5810 EP 5812 DI 10.1063/1.372530 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200369 ER PT J AU Rhyne, JJ Kaiser, H Stumpe, L Mitchell, JF McCloskey, T Chourasia, AR AF Rhyne, JJ Kaiser, H Stumpe, L Mitchell, JF McCloskey, T Chourasia, AR TI Spin dynamics and absence of a central peak anomaly in La0.67Ca0.33MnO3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID COLOSSAL-MAGNETORESISTANCE; LA1-XSRXMNO3; MANGANITES AB Low-angle inelastic neutron scattering was used to study the temperature and wave vector dependence of the spin waves in La0.67Ca0.33MnO3 perovskite-based colossal magnetoresistance material. At low q the spin waves show Heisenberg ferromagnetic dispersion (E=Dq(2)+Delta) where D is the spin stiffness, q is the wave vector, and Delta is the energy gap. However, the temperature renormalization of the spin stiffness D is anomalous, and as T increases toward T-c, D does not show the expected power law collapse, but rather exhibits a sudden sharp drop suggestive of a first-order phase transition. Detailed neutron measurements of the order parameter in zero applied field showed a similar first-order-like transition. However, no temperature hysteresis was observed in either D or in the magnetization. (C) 2000 American Institute of Physics. [S0021-8979(00)42408-4]. C1 Univ Missouri, Dept Phys, Columbia, MO 65211 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Texas A&M Univ, Dept Phys, Commerce, TX 75429 USA. RP Rhyne, JJ (reprint author), Univ Missouri, Dept Phys, Columbia, MO 65211 USA. NR 10 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5813 EP 5815 DI 10.1063/1.372531 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200370 ER PT J AU Rosenkranz, S Osborn, R Mitchell, JF Vasiliu-Doloc, L Lynn, JW Sinha, SK AF Rosenkranz, S Osborn, R Mitchell, JF Vasiliu-Doloc, L Lynn, JW Sinha, SK TI Low-energy spin-wave excitations in the bilayer manganite La1.2Sr1.8Mn2O7 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID T-C; GIANT MAGNETORESISTANCE; DYNAMICS; LA1.4SR1.6MN2O7; TRANSITION; CRYSTALS; STATE AB Inelastic neutron scattering experiments were performed on a single crystal of the bilayer manganite La1.2Sr1.8Mn2O7. Low-energy spin-wave excitations were observed along the c direction with a maximum energy of similar to 0.5 meV at the zone boundary. The dispersion of these acoustic spin wave modes is modeled by a nearest-neighbor Heisenberg model with an interbilayer exchange interaction between neighboring spins in different bilayers of 0.048(1) meV and an anisotropy gap of Delta = 0.077(3) meV. These results confirm the two-dimensional nature of the spin correlations in the bilayer manganites, with a ratio of the in-plane to interbilayer interaction of similar to 200. The temperature dependence of the energies and intensities of the spin wave excitations are in agreement with our earlier conclusion that the ferromagnetic transition is second order. (C) 2000 American Institute of Physics. [S0021-8979(00)42508-9]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Rosenkranz, S (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Osborn, Raymond/E-8676-2011; Rosenkranz, Stephan/E-4672-2011 OI Osborn, Raymond/0000-0001-9565-3140; Rosenkranz, Stephan/0000-0002-5659-0383 NR 25 TC 17 Z9 17 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5816 EP 5818 DI 10.1063/1.372532 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200371 ER PT J AU Vlasko-Vlasov, VK Lin, Y Welp, U Crabtree, GW Miller, DJ Nikitenko, VI AF Vlasko-Vlasov, VK Lin, Y Welp, U Crabtree, GW Miller, DJ Nikitenko, VI TI Observation of the structural phase transition in manganite films by magneto-optical imaging SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MAGNETORESISTANCE AB A high-resolution magneto-optical imaging technique is used to reveal the formation of twins occurring during a martensitic phase transition at similar to 105 K in La(2/3)Ca(1/3)MnO(3) (LCMO) films grown on SrTiO(3) (STO) substrates. The magnetic contrast arises due to the magneto-elastic tilts of the Mn- magnetic moments in the twins. Different magnetic structures are found in LCMO films grown on MgO, NGO, and LAO substrates showing the importance of the substrate material for the manganite film properties. (C) 2000 American Institute of Physics. [S0021-8979(00)42708-8]. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Russia. RP Vlasko-Vlasov, VK (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM vlasko-vlasov@anl.gov NR 10 TC 13 Z9 13 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5828 EP 5830 DI 10.1063/1.372536 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200375 ER PT J AU Roy, M Mitchell, JF Schiffer, P AF Roy, M Mitchell, JF Schiffer, P TI Time dependent effects and transport evidence for phase separation in La0.5Ca0.5MnO3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MAGNETIC-FIELD; MN-55 NMR; CHARGE; LA1-XCAXMNO3; MANGANITES; MAGNETORESISTANCE; LA-139; DIFFRACTION; TRANSITION; STATES AB The ground state of La1-xCaxMnO3 changes from a ferromagnetic metallic to an antiferromagnetic charge-ordered state as a function of Ca concentration at x similar to 0.50. We present evidence from transport measurements on a sample with x=0.50 that the two phases can coexist, in agreement with other observations of phase separation in these materials. We also observe that, by applying and then removing a magnetic field to the mainly charge-ordered state at some temperatures, we can "magnetically anneal" the charge order, resulting in a higher zero-field resistivity. We also observe logarithmic time dependence in both resistivity and magnetization after a field sweep at low temperatures. (C) 2000 American Institute of Physics. [S0021- 8979(00)42808-2]. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Roy, M (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RI Schiffer, Peter/F-3227-2011; OI Schiffer, Peter/0000-0002-6430-6549 NR 33 TC 26 Z9 26 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5831 EP 5833 DI 10.1063/1.372537 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200376 ER PT J AU Pufall, MR Berger, A AF Pufall, MR Berger, A TI Studying the reversal mode of the magnetization vector versus applied field angle using generalized magneto-optical ellipsometry SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc AB We used the technique of vector generalized magneto-optical ellipsometry to study the behavior of the magnetization vector of a 50 nm Co thin film as a function of external field magnitude and direction. We determined the relative contributions of magnetization rotation and domain formation to the reversal of M. The Co sample had a uniaxial in-plane anisotropy. When the angle between the applied field and the easy axis was greater than similar to 40 degrees, the reversal occurred primarily by rotation of the magnetization, accompanied by a small reduction of the magnitude of M. In this angular region, the field at which there is a large jump in the angle of M as a function of applied field angle followed a single domain coherent rotation model. However, at applied field angles less than 40 degrees to the easy axis, a larger reduction in \M\ occurred during the jump in the magnetization angle. The jump also occurred at fields much lower than those predicted by the coherent rotation model, indicating a reversal mode initiated by domain formation. (C) 2000 American Institute of Physics. [S0021-8979(00)90908-3]. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif San Diego, Ctr Magnetic Recording Res, La Jolla, CA 92093 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Pufall, MR (reprint author), Univ Calif San Diego, Dept Phys, 9500 Gilman Dr, La Jolla, CA 92093 USA. RI Berger, Andreas/D-3706-2015 OI Berger, Andreas/0000-0001-5865-6609 NR 5 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5834 EP 5836 DI 10.1063/1.372538 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200377 ER PT J AU Orgassa, D Fujiwara, H Schulthess, TC Butler, WH AF Orgassa, D Fujiwara, H Schulthess, TC Butler, WH TI Disorder dependence of the magnetic moment of the half-metallic ferromagnet NiMnSb from first principles SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID ELECTRONIC-STRUCTURE; MAGNETORESISTANCE; PTMNSB; FILMS AB Using half-metallic ferromagnets in spin-dependent devices, like spin valves and ferromagnetic tunnel junctions, is expected to increase the device performance. However, using the half-metallic ferromagnet NiMnSb in such devices led to much less than ideal results. One of the possible sources for this behavior is atomic disorder. First-principles calculations of the influence of atomic disorder on the electronic structure of NiMnSb underline the sensitivity of half-metallic properties in NiMnSb to atomic disorder. In this article, we report on the disorder dependence of the total magnetic moment calculated by applying the layer Korringa-Kohn-Rostoker method in conjunction with the coherent potential approximation. We consider the following types of disorder: (1) intermixing of Ni and Mn, (2) partial occupancy of a normally vacant lattice site by Ni and Mn, and (3) partial occupancy of this site by Mn and Sb. In all cases the composition is kept stoichiometric. All three types of disorder decrease the moment monotonically with increasing disorder levels. For the experimentally seen disorder of 5% Mn and 5% Sb on the normally vacant lattice site, the total moment is decreased by 4.1%. The results suggest that precise measurement of the saturation magnetization of NiMnSb thin films can give information on the disorder. (C) 2000 American Institute of Physics. [S0021-8979(00)50008-5]. C1 Univ Alabama, Ctr Mat Informat Technol MINT, Tuscaloosa, AL 35487 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Orgassa, D (reprint author), Univ Alabama, Ctr Mat Informat Technol MINT, Tuscaloosa, AL 35487 USA. NR 13 TC 30 Z9 30 U1 2 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5870 EP 5871 DI 10.1063/1.372550 PN 2 PG 2 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200389 ER PT J AU Schneider, G Jansen, HJF AF Schneider, G Jansen, HJF TI Role of orbital polarization in calculations of the magnetic anisotropy SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MAGNETOCRYSTALLINE ANISOTROPY; METALS; ENERGY; SYSTEMS; COBALT; NICKEL; IRON AB Magnetic anisotropy is a difficult topic to describe by electronic structure theory. The results of ab initio calculations for iron and nickel are disappointing, especially since these calculations require high numerical precision and are very time consuming. For iron the value of the energy is too small by a factor of 3, while for nickel the sign is wrong and the value is too small by a factor of 5. The local density approximation can be improved by adding corrections that mimic the inclusion of Hund's second rule. This is equivalent to increasing the effective spin-orbit parameter. For iron a small increase in the effective spin-orbit parameter is sufficient to reconcile theory and experiment. For nickel, this is not possible. (C) 2000 American Institute of Physics. [S0021-8979(00)66108-X]. C1 Oregon State Univ, Dept Phys, Corvallis, OR 97331 USA. RP Brookhaven Natl Lab, Upton, NY 11973 USA. EM henri@physics.orst.edu NR 24 TC 5 Z9 5 U1 0 U2 2 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 MAY 1 PY 2000 VL 87 IS 9 BP 5875 EP 5877 DI 10.1063/1.372552 PN 2 PG 3 WC Physics, Applied SC Physics GA 308RT UT WOS:000086727200391 ER PT J AU Rosenkranz, S Ramirez, AP Hayashi, A Cava, RJ Siddharthan, R Shastry, BS AF Rosenkranz, S Ramirez, AP Hayashi, A Cava, RJ Siddharthan, R Shastry, BS TI Crystal-field interaction in the pyrochlore magnet Ho2Ti2O7 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID LOW-TEMPERATURE PROPERTIES; FRUSTRATION; ICE AB Neutron time-of-flight spectroscopy has been employed to study the crystal-field interaction in the pyrochlore titanate Ho2Ti2O7. The crystal-field parameters and corresponding energy-level scheme have been determined from a profile fit to the observed neutron spectra. The ground state is a well separated E-g doublet with a strong Ising-like anisotropy, which can give rise to frustration in the pyrochlore lattice. Using the crystal-field parameters determined for the Ho compound as an estimate of the crystal-field potential in other pyrochlore magnets, we also find the Ising type behavior for Dy. In contrast, the almost planar anisotropy found for Er and Yb prevents frustration, because of the continuous range of possible spin orientations in this case. (C) 2000 American Institute of Physics. [S0021- 8979(00)22908-3]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Princeton Univ, Dept Chem, Princeton, NJ 08540 USA. Indian Inst Sci, Dept Phys, Bangalore 560012, Karnataka, India. RP Rosenkranz, S (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Rosenkranz, Stephan/E-4672-2011 OI Rosenkranz, Stephan/0000-0002-5659-0383 NR 16 TC 111 Z9 111 U1 1 U2 16 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5914 EP 5916 DI 10.1063/1.372565 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800008 ER PT J AU Larson, DJ Martens, RL Kelly, TF Miller, MK Tabat, N AF Larson, DJ Martens, RL Kelly, TF Miller, MK Tabat, N TI Atom probe analysis of planar multilayer structures SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID ION SPECIMEN PREPARATION; FILMS AB Atom probe field ion microscopy has been used to analyze a planar-deposited layered structure in plan view. The specimens were prepared with a newly developed method that involves a combination of photolithography and focused ion-beam milling. A multilayer structure consisting of {Ta/CoFe/(Cu/CoFe)(15)/Ru/(CoFe/Ru)(5)/Ru/NiFe} was sputter deposited for use as a test stack. The corresponding thicknesses of these layers were 7/13(3/3)/50/(3/1)/50/150 nm. The nanometer-scale periodicity of the Cu/CoFe stack is readily apparent in transmission electron microscopy images of a field ion specimen fabricated from this material, suggesting that the specimen preparation procedure does not lead to destruction of the multilayer structure. Atom probe analysis of the bulk NiFe layer and the Ru/NiFe interface revealed the distribution of impurity atoms in the film, and these may affect the magnetic properties of the multilayers. Whereas a uniform distribution of C, N and Ar was observed, segregation of O was observed in the NiFe layer within similar to 0.25 nm of the interphase interface, with a concentration greater than 20 times that found in the bulk of the NiFe layer. (C) 2000 American Institute of Physics. [S0021-8979(00)17308-6]. C1 Seagate Technol, Recording Head Operat, Minneapolis, MN 55435 USA. Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Larson, DJ (reprint author), Seagate Technol, Recording Head Operat, 7801 Comp Ave S, Minneapolis, MN 55435 USA. NR 12 TC 19 Z9 19 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 5989 EP 5991 DI 10.1063/1.372589 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800033 ER PT J AU Bennett, LH Waterstrat, RM Swartzendruber, LJ Bendersky, LA Brown, HJ Watson, RE AF Bennett, LH Waterstrat, RM Swartzendruber, LJ Bendersky, LA Brown, HJ Watson, RE TI Magnetism and incommensurate waves in Zr-3(Rh1-xPdx)(4) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID ZR; PHASE AB Unique properties of the Zr-3(Rh(1-x)Pdx)(4) alloy system are reported here. Contrary to most metallically bonded systems which are not quick to change magnetic behavior with alloy concentration, this system does. Pure Zr3Rh4 and pure Zr3Pd4 are each nonmagnetic, while in the limited range 0.02 < x < 0.08, there is a substantial increase in paramagnetism, attended by a similarly varying incommensurate density wave. At x=0.04 the system exhibits ferromagnetism and displays some superconductivity at x=0.06. The crystal structure involves disclination lines of Rh atoms, or channels, which are equivalent to those of the superconducting A15 structures and bear resemblances to those of the hard magnets. (C) 2000 American Institute of Physics. [S0021-8979(00)17808-9]. C1 George Washington Univ, Ashburn, VA 20147 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Bennett, LH (reprint author), George Washington Univ, Ashburn, VA 20147 USA. NR 7 TC 4 Z9 4 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6016 EP 6018 DI 10.1063/1.372598 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800042 ER PT J AU Hill, P Miller, LL AF Hill, P Miller, LL TI Magnetic properties of the rare-earth silicide Ho5Si3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc AB Despite their simple chemical formula and hexagonal structure, the magnetic and electrical properties of the family of rare-earth silicides R5Si3 have not been systematically investigated. To begin our systematic study of this system, we have synthesized Ho5Si3 and completed magnetic and resistivity measurements on this sample. AC susceptibility measurements show Ho5Si3 to have mu(eff)=10.5 mu(B)/Ho atom and theta=16.5 K. Magnetic measurements indicate that Ho5Si3 undergoes two transitions at low temperatures, the first at 24 K is an antiferromagnetic transition, while the second, at about 8 K, is ferromagnetic. Low temperature measurements as a function of field reveal a metamagnetic transition at H-c=2.2 T. The behavior of this sample is consistent with the complicated low temperature ordering found in other members of this series. (C) 2000 American Institute of Physics. [S0021-8979(00)18208-8]. C1 Univ No Iowa, Dept Phys, Cedar Falls, IA 50614 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. RP Hill, P (reprint author), Univ No Iowa, Dept Phys, Cedar Falls, IA 50614 USA. NR 10 TC 8 Z9 9 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6034 EP 6036 DI 10.1063/1.372604 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800048 ER PT J AU Allen, JW Gweon, GH Schek, HT Liu, LZ Tjeng, LH Park, JH Ellis, WP Chen, CT Gunnarsson, O Jepsen, O Andersen, OK Dalichaouch, Y Maple, MB AF Allen, JW Gweon, GH Schek, HT Liu, LZ Tjeng, LH Park, JH Ellis, WP Chen, CT Gunnarsson, O Jepsen, O Andersen, OK Dalichaouch, Y Maple, MB TI Kondo resonance behavior of heavy fermion f-electron materials (invited) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID INVARIANT PHOTOELECTRON-SPECTRA; CESI2 PHOTOEMISSION SPECTRA; ALPHA-GAMMA-TRANSITION; SINGLE IMPURITY MODEL; X-RAY-ABSORPTION; 5 MEV RESOLUTION; CE COMPOUNDS; TEMPERATURE-DEPENDENCE; ANDERSON MODEL; INTERMETALLIC COMPOUNDS AB The Kondo properties of the impurity Anderson model provide a theoretical framework for relating thermodynamic and angle integrated electron spectroscopy data in many heavy fermion materials. We describe the success and the challenges of this approach, summarize a detailed analysis of CeSi2, and give a perspective on the relation to the lattice Anderson model. (C) 2000 American Institute of Physics. [S0021-8979(00)93508-4]. C1 Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. Yale Univ, Dept Appl Phys, New Haven, CT 06520 USA. AT&T Bell Labs, Murray Hill, NJ 07974 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Allen, JW (reprint author), Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. NR 55 TC 13 Z9 13 U1 2 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6088 EP 6091 DI 10.1063/1.373421 PN 3 PG 4 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800064 ER PT J AU Shield, JE Kappes, BB Crew, DC Branagan, DJ AF Shield, JE Kappes, BB Crew, DC Branagan, DJ TI Exchange coupling in crystalline/amorphous Nd-Fe-B nanoassemblies SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID REVERSIBLE MAGNETIZATION AB The demagnetization behavior of nanoassembled crystalline/amorphous microstructures was investigated. The microstructures consisted of isolated Nd2Fe14B crystallites surrounded by regions of remaining amorphous phase. The hard magnetic crystallites interacted with the surrounding amorphous phase over a length scale of approximately 1.5-2 nm. As the extent of the amorphous phase decreased to less than this, interactions between hard magnetic grains were observed. (C) 2000 American Institute of Physics. [S0021-8979(00)66208-4]. C1 Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Shield, JE (reprint author), Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. NR 9 TC 2 Z9 2 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6113 EP 6115 DI 10.1063/1.372626 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800072 ER PT J AU Kim, J Barmak, K De Graef, M Lewis, LH Crew, DC AF Kim, J Barmak, K De Graef, M Lewis, LH Crew, DC TI Effect of annealing on magnetic exchange coupling in CoPt/Co bilayer thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID PERMANENT-MAGNETS AB Thin film CoPt/Co bilayers have been prepared as a model system to investigate the relationship between microstructure and exchange coupling in two-phase nanocomposite permanent magnets. The bilayers were prepared by magnetron sputter deposition of near-equiatomic CoPt with a thickness of 25 nm onto oxidized Si wafers. In the as-deposited state, CoPt had the A1 (fcc) structure and was magnetically soft. Before reinsertion into the sputtering chamber for the deposition of 2.8-16.7 nm thick Co layers, the CoPt films were annealed at 700 degrees C for 120 min to produce the magnetically hard, fully ordered L1(0) phase. The presence of exchange coupling in the bilayers was verified by magnetic hysteresis and recoil measurements and showed that only for Co thicknesses below 6.3 nm was this layer (in its as-deposited state) coupled through its full thickness to the CoPt layer. Annealing the bilayer samples at 300 and 550 degrees C for 20 min resulted in improvement of the interlayer magnetic coupling and produced clear differences in the magnetic reversal coherency and the recoil curves. However, for some samples, the improved coupling resulted in a decrease in coercivity, indicating that there is an optimum in the coupling strength for the attainment of high coercivity. Transmission electron microscopy studies of the bilayers in plan view showed that the increased interlayer coupling with annealing was a result of improved granular epitaxy of Co to CoPt. (C) 2000 American Institute of Physics. [S0021-8979(00)52208-7]. C1 Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. Brookhaven Natl Lab, Dept Appl Sci, Div Chem & Mat Sci, Upton, NY 11973 USA. RP Kim, J (reprint author), Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. RI Barmak, Katayun/A-9804-2008; DeGraef, Marc/G-5827-2010 OI Barmak, Katayun/0000-0003-0070-158X; DeGraef, Marc/0000-0002-4721-6226 NR 9 TC 19 Z9 19 U1 0 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6140 EP 6142 DI 10.1063/1.372635 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800081 ER PT J AU Furukawa, Y Lascialfari, A Jang, ZH Borsa, F AF Furukawa, Y Lascialfari, A Jang, ZH Borsa, F TI Proton spin-lattice relaxation at low temperature in the ferromagnetic spin ring Cu6 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID DYNAMICS; MAGNETS; H-1-NMR AB We report H-1 nuclear magnetic resonance spin-lattice relaxation rate (NSLR) measurements as a function of temperature (1.5-4.2 K) and as a function of applied magnetic field (0.2-8.2 T) in the molecular magnet [(PhSiO2)(6)Cu-6(O2SiPh)(6)] in short Cu6. The results are explained in terms of a simple model whereby the NSLR is driven by the fluctuations of the local hyperfine field due to the reorientation of the total spin of the molecule in its ground state. From the analysis of the data, we infer the temperature and field dependence of the characteristic rate of the fluctuations of the total magnetization of the Cu6 ring in its ground state. (C) 2000 American Institute of Physics. [S0021-8979(00)52508-0]. C1 Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Ames Lab, Ames, IA 50011 USA. Univ Pavia, Dipartimento Fis Gen A Volta, I-27100 Pavia, Italy. INFM, I-27100 Pavia, Italy. RP Furukawa, Y (reprint author), Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. NR 11 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6265 EP 6267 DI 10.1063/1.372674 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800121 ER PT J AU Al-Saqer, M Dobrovitski, VV Harmon, BN Katsnelson, MI AF Al-Saqer, M Dobrovitski, VV Harmon, BN Katsnelson, MI TI Many-spin effects and tunneling properties of magnetic molecules SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID QUANTUM; NANOMAGNET; RELAXATION; CLUSTERS; MN-12 AB Spin tunneling in molecular magnets has attracted much attention, however theoretical considerations of this phenomenon up to now have not taken into account the many-spin nature of molecular magnets. We present, to our knowledge, the first successful attempt of a realistic calculation of tunneling splittings for Mn-12 molecules, thus achieving a quantitatively accurate many-spin description of a real molecular magnet in the energy interval ranging from about 100 K down to 10(-12) K. Comparison with the results of the standard single-spin model shows that many-spin effects affect the tunneling splittings considerably. The values of ground state splitting given by single-spin and many-spin models differ from each other by a factor of 5. (C) 2000 American Institute of Physics. [S0021-8979(00)66308-9]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Al-Saqer, M (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Katsnelson, Mikhail/D-4359-2012 NR 16 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6268 EP 6270 DI 10.1063/1.372675 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800122 ER PT J AU Moze, O Rosenkranz, S Osborn, R Buschow, KHJ AF Moze, O Rosenkranz, S Osborn, R Buschow, KHJ TI Magnetic excitations in tetragonal HoCr2Si2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID INELASTIC NEUTRON-SCATTERING; CRYSTAL-FIELD; INTERMETALLIC COMPOUNDS; THCR2SI2 STRUCTURE AB Magnetic excitations in tetragonal HoCr2Si2 have been measured by neutron spectroscopy. The temperature and Q dependence of the excitations measured at 8 K confirm that they can be attributed to crystal field (CF) dipolar transitions experienced by the Ho ion. The analysis of the neutron spectroscopy data for HoCr2Si2 is simplified by the fact that the CF coefficients have already been determined for the series RX2Si2 (R=rare earth, X=Cu, Ni) by neutron spectroscopy. In addition, electronic band structure calculations and experimental determinations of the electric field gradient for numerous compounds of the type RT2Si2 (T=Cr, Cu, Ni) show that the first-order CF coefficient, A(2)(0), changes sign when passing from the series RX2Si2 (X=Cr, Ni) to RCu2Si2. In the light of this information, the available neutron spectroscopy data for HoCr2Si2 are presented and discussed. (C) 2000 American Institute of Physics. [S0021-8979(00)52708-X]. C1 Univ Modena & Reggio Emilia, Dipartimento Fis, INFM, I-41100 Modena, Italy. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60436 USA. Univ Amsterdam, Van der Waals Zeeman Inst, NL-1018 XE Amsterdam, Netherlands. RP Moze, O (reprint author), Univ Modena & Reggio Emilia, Dipartimento Fis, INFM, Via G Campi 213-A, I-41100 Modena, Italy. RI Osborn, Raymond/E-8676-2011; Rosenkranz, Stephan/E-4672-2011 OI Osborn, Raymond/0000-0001-9565-3140; Rosenkranz, Stephan/0000-0002-5659-0383 NR 13 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6283 EP 6285 DI 10.1063/1.372680 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800127 ER PT J AU Kusinski, GJ Krishnan, KM Thomas, G Nelson, EC AF Kusinski, GJ Krishnan, KM Thomas, G Nelson, EC TI Domain structures and temperature-dependent spin reorientation transitions in c-axis oriented Co-Cr thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID PERPENDICULAR MAGNETIC-ANISOTROPY AB Highly c-axis oriented Co95Cr5 films with perpendicular anisotropy were grown epitaxially on Si (111), using an Ag seed layer, by physical vapor deposition. Films were characterized by x-ray diffraction, transmission electron microscopy (TEM), selected area electron diffraction, and Lorentz microscopy in a TEM. The following epitaxial relationship was confirmed: (111)(Si)parallel to(111)(Ag)parallel to(0001)(CoCr);[(2) over bar 20](Si)parallel to[(2) over bar 20](Ag)parallel to[(1) over bar 100](CoCr). Magnetic domain structures of these films were observed as a function of thickness; t, in the range, 200 Angstrom < t < 700 Angstrom using a wedge-shaped sample, and temperature-dependent measurements were carried out by in situ resistance heating. Thickness was measured locally by electron energy loss spectroscopy. At room temperature, below a critical thickness, t(c)approximate to 300 Angstrom, the magnetization was found to be effectively in-plane of the film, and above t(c) a regular, stripe-like domain pattern with a significant, alternating in sign, perpendicular component was observed. The spin reorientation transitions of the stripe domains to the in-plane magnetization were studied dynamically by observing the domains as a function of temperature by in situ heating up to 350 degrees C. The critical transition thickness, t(c), which is a function of K-u and magnetostatic energy, was found to increase with increasing temperature. The stripe-domain period, L observed at room temperature was found to increase gradually with thickness; L=90 nm at t=300 Angstrom, and L=110 nm at t=700 Angstrom. (C) 2000 American Institute of Physics. [S0021-8979(00)46408-X]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Kusinski, GJ (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. NR 11 TC 8 Z9 8 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6376 EP 6378 DI 10.1063/1.372711 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800158 ER PT J AU Midzor, MM Wigen, PE Pelekhov, D Chen, W Hammel, PC Roukes, ML AF Midzor, MM Wigen, PE Pelekhov, D Chen, W Hammel, PC Roukes, ML TI Imaging mechanisms of force detected FMR microscopy SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID FERROMAGNETIC-RESONANCE; FILMS AB We demonstrate spatial resolution of ferromagnetic resonance in a microscopic sample of YIG using ferromagnetic resonance force microscopy (FMRFM). Measurements were performed on a small single crystal YIG film grown on a GGG substrate, roughly rectangular in shape 20 mu mx similar to 150 mu m and 3 mu m thick. The perpendicular and parallel force geometries of FMRFM, in conjunction with an external bias field both parallel and perpendicular to the film, were used to scan the sample. This enabled the detection of strong signals, even at atmospheric pressure and room temperature. The fundamental and higher-order magnetostatic modes were observed to have 26-29 Gauss separation. The intensity of these modes exhibited spatial variation as the magnetic tip was scanned over the sample, and this behavior is qualitatively explained by DE theory. An improved fabrication method for magnet on cantilever was employed, which yielded a spatial resolution of 15 mu m. These results demonstrate the potential of FMRFM for investigating the spatial dependence of ferromagnetic resonance, and for studying the anisotropy fields and exchange coupling effects within multilayer films and small magnetic systems. (C) 2000 American Institute of Physics. [S0021-8979(00)80608-8]. C1 CALTECH, Pasadena, CA 91125 USA. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Midzor, MM (reprint author), CALTECH, Pasadena, CA 91125 USA. RI Roukes, Michael/E-9787-2010; Hammel, P Chris/O-4845-2014 OI Hammel, P Chris/0000-0002-4138-4798 NR 7 TC 36 Z9 36 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6493 EP 6495 DI 10.1063/1.372748 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800197 ER PT J AU Lo, CCH Tang, F Biner, SB Jiles, DC AF Lo, CCH Tang, F Biner, SB Jiles, DC TI Effects of fatigue-induced changes in microstructure and stress on domain structure and magnetic properties of Fe-C alloys SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID DEPENDENCE; STEELS; DAMAGE AB A study of the effects of microstructural changes on domain structure and magnetic properties as a result of fatigue has been made on Fe-C alloys subjected to either cold work, stress-relief annealing, or heat treatment that produced a ferritic/pearlitic structure. The magnetic properties varied with stress cycling depending on the initial condition of the samples. Variations in coercivity in the initial stage of fatigue were closely related to the changes in dislocation structure. In the intermediate stage of fatigue the observed refinement of domain structures was related to the development of dislocation cell structures and formation of slip bands. In the final stage of fatigue the remanence and maximum permeability decreased dramatically, and this rate of decrease was dependent on the crack propagation rate. (C) 2000 American Institute of Physics. [S0021-8979(00)77008-3]. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Lo, CCH (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RI Jiles, David/H-9548-2012 NR 9 TC 10 Z9 11 U1 0 U2 13 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6520 EP 6522 DI 10.1063/1.372757 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800206 ER PT J AU Montenegro, FC Belanger, DP Slanic, Z Fernandez-Baca, JA AF Montenegro, FC Belanger, DP Slanic, Z Fernandez-Baca, JA TI d=3 random field behavior near percolation SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID ISING SYSTEM FEXZN1-XF2; SPIN-GLASS BEHAVIOR; NEUTRON-SCATTERING; ANTIFERROMAGNET; THRESHOLD; CROSSOVER; FE0.31ZN0.69F2 AB The highly diluted antiferromagnet Mn0.35Zn0.65F2 has been investigated by neutron scattering for H > 0. A low-temperature (T < 11 K), low-field (H < 1 T) pseudophase transition boundary separates a partially antiferromagnetically ordered phase from the paramagnetic one. For 1 < H < 7 T at low temperatures, a region of antiferromagnetic order is field induced but is not enclosed within a transition boundary. (C) 2000 American Institute of Physics. [S0021-8979(00)48908-5]. C1 Univ Fed Pernambuco, Dept Fis, BR-50670901 Recife, PE, Brazil. Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Montenegro, FC (reprint author), Univ Fed Pernambuco, Dept Fis, BR-50670901 Recife, PE, Brazil. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 20 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6537 EP 6539 DI 10.1063/1.372762 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800212 ER PT J AU Crew, DC Lewis, LH Welch, DO Panchanathan, V AF Crew, DC Lewis, LH Welch, DO Panchanathan, V TI Effect of degree of die upset on magnetic behavior in Nd-13.9(Fe0.92Co0.08)(80.3)B5.3Ga0.5 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID FE-B MAGNETS; NDFEB; COERCIVITY AB DC demagnetization (DCD), isothermal remanent magnetization (IRM), and reversible magnetization measurements were used to examine the magnetic reversal behavior in melt-quenched samples of composition Nd-13.9(Fe0.92Co0.08)(80.3)B5.3Ga0.5 subjected to different levels of thermomechanical deformation (die upsetting). The reversible magnetization measurements indicate that in the thermally demagnetized condition domain walls are present within the material for all levels of deformation. During demagnetization from a saturated state, domain walls are present in a minority of grains at low levels of deformation but these domain walls disappear at higher levels of deformation. This behavior is explained in terms of changes in the relative strengths of nucleation and pinning fields. Comparison of these results to previous results obtained on similar materials indicate that changes in the magnetization behavior with degree of deformation are more marked in samples which are free of Ga, indicating that Ga additions act to suppress the nucleation of new domain walls, presumably in the grain boundaries. (C) 2000 American Institute of Physics. [S0021-8979(00)23808-5]. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Magnequench Int Inc, Anderson, IN USA. RP Crew, DC (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 14 TC 2 Z9 2 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6570 EP 6572 DI 10.1063/1.372773 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800223 ER PT J AU Cheng, N Krishnan, KM Girt, E Farrow, RFC Marks, RF Kellock, A Young, A Huan, CHA AF Cheng, N Krishnan, KM Girt, E Farrow, RFC Marks, RF Kellock, A Young, A Huan, CHA TI Exchange biasing and interface structure in MnNi/Fe(Mo) bilayers SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID FILMS; ANISOTROPY; MODEL AB The role of magnetic, structural, and chemical roughness on the origin of exchange biasing in polycrystalline Mn52Ni48/Fe-92(Mo-8) bilayers has been investigated by transmission x-ray magnetic circular dichroism (XMCD), vibrating sample magnetometry (VSM), and transmission electron microscopy (TEM). Three bilayer samples of MnNi(22 nm)/Fe(Mo) (6 nm) were grown by molecular beam epitaxy under ultrahigh vacuum conditions with the MnNi layer at temperatures of 200 degrees C, 250 degrees C, and 300 degrees C. The exchange bias, H-e was observed to be the largest for the 250 degrees C growth sample. The angular dependence of H-e can be well modeled in terms of a cosine series with odd terms confirming the unidirectional nature of the anisotropy energy. However, the coefficients are different for the three samples indicating different microscopic magnetic interactions at the interface. XMCD measurements showed no magnetic moment for Mn and Ni but showed systematic variations of the Fe moment, i.e., a decrease in Fe moment with increase in H-e was observed. We have interpreted this decrease in Fe moment in terms of antiferromagnetic (AF) ordering of Fe at the interface with the extent of the AF ordering being related to the magnitude of the exchange. Thus, for samples grown at 250 degrees C, it is found that at least about 4 MLs of Fe appear to be AF. Preliminary energy-filtered imaging of cross-section samples shows that the Fe layer is chemically rough suggesting that the decrease in moment may arise from the intermixing of Fe with the MnNi layer. (C) 2000 American Institute of Physics. [S0021-8979(00)68908-9]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Krishnan, KM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 14 TC 6 Z9 6 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6647 EP 6649 DI 10.1063/1.372798 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800248 ER PT J AU Pechan, MJ Teng, N Stewart, JD Hilt, JZ Fullerton, EE Jiang, JS Sowers, CH Bader, SD AF Pechan, MJ Teng, N Stewart, JD Hilt, JZ Fullerton, EE Jiang, JS Sowers, CH Bader, SD TI Anisotropy determination in epitaxial Sm-Co/Fe exchange springs SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID FILMS; BILAYERS; MAGNETS; GROWTH; CO AB We report in-plane anisotropy in epitaxial Sm-Co(x)/Fe(y) bilayers as determined by ferromagnetic resonance (FMR). Four samples, (x,y)=(35, 30) and (20, 20) nm each on MgO (110) and (100) substrates, have been prepared via magnetron sputtering. The two substrate orientations result in twofold and fourfold Sm-Co symmetry respectively, with the Sm-Co c-axis in-plane. Magnetization curves indicate elastic exchange spring Fe behavior in reversing fields up to the Sm-Co switching fields (6 and 8 kG at room temperature in the (35, 30) and (20, 20) nm films, respectively). 35 GHz in-plane FMR measurements were made in order to map the crystalline anisotropy of the Fe layer as well as the induced anisotropy from the exchange coupling to the Sm-Co layer. The twofold Sm-Co samples exhibit a clear superposition of the near fourfold Fe crystal field anisotropy (530 Oe) and the unidirectional exchange-bias anisotropy (approximate to 650 Oe) arising from the Fe/Sm-Co interface. The crystalline Fe anisotropy in the fourfold Sm-Co samples is less well defined, presumably due to poorer epitaxy of the Fe layer for this orientation. (C) 2000 American Institute of Physics. [S0021-8979(00)88008-1]. C1 Miami Univ, Dept Phys, Oxford, OH 45056 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Pechan, MJ (reprint author), Miami Univ, Dept Phys, Oxford, OH 45056 USA. RI Bader, Samuel/A-2995-2013; Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 13 TC 27 Z9 28 U1 2 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6686 EP 6688 DI 10.1063/1.372808 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800258 ER PT J AU Meacham, BE Shield, JE Branagan, DJ AF Meacham, BE Shield, JE Branagan, DJ TI Order-disorder effects in nitrided Sm-Fe permanent magnets SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID ALLOYS AB Rapidly solidified Sm11Fe89 was observed to form partially ordered Sm2Fe17. The ordering increased systematically with annealing temperature, reaching an order parameter of 0.8 after annealing at 950 degrees C for 15 min. The coercivity of the corresponding interstitial compound Sm2Fe17Nx varied with annealing temperature and thus order parameter. The coercivity reached a maximum for an order parameter of 0.45-5, then dramatically decreased as the order increased. This behavior is characteristic of demagnetization controlled by domain wall pinning by antiphase boundaries. (C) 2000 American Institute of Physics. [S0021-8979(00)91008-9]. C1 Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Meacham, BE (reprint author), Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. NR 12 TC 12 Z9 12 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6707 EP 6709 DI 10.1063/1.372815 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800265 ER PT J AU Zhang, Y Corte-Real, M Hadjipanayis, GC Liu, JF Walmer, MS Krishnan, KM AF Zhang, Y Corte-Real, M Hadjipanayis, GC Liu, JF Walmer, MS Krishnan, KM TI Magnetic hardening studies in sintered Sm(Co,Cu-x,Fe,Zr)(z) 2 : 17 high temperature magnets SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID PERMANENT-MAGNETS; COERCIVITY AB Lorentz microscopy combined with conventional transmission electron microscopy were used to image the magnetic domains and microstructures of sintered Sm(CobalCuxFe0.06Zr0.03)(z) (0.088 less than or equal to x less than or equal to 0.128; 5.8 less than or equal to z less than or equal to 7.2) permanent magnets which were specifically designed for high temperature applications. The microstructural data were correlated with the magnetic measurements to understand the origin of coercivity. All sintered magnets showed typical cellular and lamellar microstructures. The cell size and coercivity were found to be more sensitive to z than to the Cu content. For a fixed Cu content, by increasing z from 5.8 to 7.2, the cell size was found to vary dramatically from 10 to 80 nm and the coercivity from 5.6 to 40 kOe, respectively. On the other hand, for fixed z, the cell size decreases slightly with increasing Cu content from 0.08 to 0.128 and the corresponding coercivity increases from 23.6 to 40 kOe. Both z and the Cu content show a smaller effect on the cell boundary width and lamella phase density. Domain wall pinning is observed in all magnets studied, irrespective of their cell size. The smaller the cell size, the less wavy the walls are, and the lower the coercivity. The Lorentz microscopy data indicate that the majority of pinning sites are the cell boundaries with occasional pinning at the intersection of cell boundaries with the lamella phase. (C) 2000 American Institute of Physics. [S0021-8979(00)29208-6]. C1 Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA. Electron Energy Corp, Landisville, PA 17538 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Zhang, Y (reprint author), Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA. NR 8 TC 16 Z9 30 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6722 EP 6724 DI 10.1063/1.372820 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800270 ER PT J AU Branagan, DJ Kramer, MJ Tang, Y McCallum, RW AF Branagan, DJ Kramer, MJ Tang, Y McCallum, RW TI Achieving optimum loop shapes in quaternary Pr-Co alloys SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MAGNETS; PRCO5 AB The magnetic properties and microstructures of a quaternary Pr-Co-Ti-C alloy were investigated. After heat treating at 800 degrees C, the quaternary alloy developed high coercivity (16.7 kOe) and high energy product (8.6 MGOe). Hysteretic loop shapes exhibiting single-phase magnetic character were achieved which was a problem which previously plagued development of Pr-Co alloys. The optimum microstructure contained 75-100 nm Pr1Co5 hard magnetic grains, 75-100 nm Pr1Co2 second phases, and < 10 nm TiC grain boundary precipitates. The important factors in achieving optimum loop shapes in Pr-Co alloys were examined in detail. (C) 2000 American Institute of Physics. [S0021-8979(00)24608-2]. C1 Idaho Natl Engn & Eenvironm Lab, Lockheed Martin Idaho Technol, Idaho Falls, ID 83415 USA. Iowa State Univ, Ames Lab, Ames, IA 50010 USA. RP Branagan, DJ (reprint author), Idaho Natl Engn & Eenvironm Lab, Lockheed Martin Idaho Technol, POB 1625, Idaho Falls, ID 83415 USA. NR 7 TC 9 Z9 9 U1 2 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6737 EP 6739 DI 10.1063/1.372825 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800275 ER PT J AU Miller, DJ Lin, YK Vlasko-Vlasov, V Welp, U AF Miller, DJ Lin, YK Vlasko-Vlasov, V Welp, U TI Grain boundary structures in La2/3Ca1/3MnO3 thin films SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID MAGNETIC-ANISOTROPY; MAGNETORESISTANCE; STRAIN; LA0.7CA0.3MNO3 AB As with many other oxide-based compounds that exhibit electronic behavior, structural defects have a strong influence on the electronic properties of the CMR manganites. In this work, we have studied the effect of grain boundaries on the transport properties and on the local orientation of magnetization. Thin films of the perovskite-related La2/3Ca1/3MnO3 compound were deposited onto bicrystal substrates using pulsed laser deposition. Transport measurements showed an enhancement of magnetoresistance across the grain boundary. The structure of the boundary was evaluated by electron microscopy. In contrast with the highly meandering boundaries typically observed in bicrystals of high-temperature superconductors, the boundaries in these films are relatively straight and well defined. However, magneto-optical imaging showed that the local magnetization was oriented out of the plane at the grain boundary while it was oriented within the plane in the grains on either side. This coordinated reorientation of local magnetization near the grain boundary leads to enhanced magnetoresistance across the boundary in low fields. (C) 2000 American Institute of Physics. [S0021-8979(00)55808-3]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Miller, DJ (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 18 TC 22 Z9 24 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6758 EP 6760 DI 10.1063/1.372832 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800282 ER PT J AU Stadler, S Idzerda, YU Chen, Z Ogale, SB Venkatesan, T AF Stadler, S Idzerda, YU Chen, Z Ogale, SB Venkatesan, T TI The effects of YBa2Cu3O7-delta overlayers on the magnetic and electronic properties of La0.7Sr0.3MnO3 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID RAY-ABSORPTION-SPECTROSCOPY; THIN-FILMS; OXYGEN DIFFUSION; SINGLE-CRYSTALS; MAGNETORESISTANCE; JUNCTIONS; DEVICES AB The effects of YBa2Cu3O7-delta (YBCO) cap layers on the magnetic and electronic properties of La0.7Sr0.3MnO3 (LSMO) underlayers was determined by x-ray magnetic circular dichroism and x-ray absorption spectroscopy techniques. The YBCO caps alter the LSMO in a way that effectively decreases the concentration of La at the LSMO/YBCO interface. (C) 2000 American Institute of Physics. [S0021-8979(00)62908-0]. C1 USN, Res Lab, Mat Phys Branch, Washington, DC 20375 USA. Univ Maryland, Ctr Superconduct Res, Dept Phys, College Pk, MD 20742 USA. RP Stadler, S (reprint author), Brookhaven Natl Lab, NSLS Bldg 725A-U4B, Upton, NY 11973 USA. RI Venkatesan, Thirumalai/E-1667-2013 NR 30 TC 11 Z9 11 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6767 EP 6769 DI 10.1063/1.372835 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800285 ER PT J AU Lin, CL Yuen, T Mihalisin, T Chu, F AF Lin, CL Yuen, T Mihalisin, T Chu, F TI The effects of Fe, Co, and Ni doping on the superconductivity and structure of HfV2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID COMPOUND; TA AB The temperature dependence of the specific heat has been measured for Fe-, Co-, and Ni-doped HfV2 systems. HfV2 undergoes a structural transformation at T-S=116 K and becomes superconducting at T-C=9 K. The low temperature specific heat of HfV2 shows an enhanced electronic specific heat coefficient indicating a large density of states at the Fermi level. T-C shows nonmonotonic behavior with magnetic ion concentration. It increases initially as one dopes HfV2 with small amounts of Fe, Co, or Ni and reaches a maximum of 9.4 K for about 3.0 to 4.0 at. % doping and then decreases for higher concentrations. On the other hand, the specific heat data at higher temperatures show that both T-S and the size of the specific heat anomaly at T-S decrease monotonically and dramatically when the concentration of Fe, Co, or Ni is increased. No evidence of a structural transformation is detected for samples with more than 5 at. % Fe, Co, or Ni. The variations of T-C and T-S can be explained qualitatively by recent theoretical calculations. (C) 2000 American Institute of Physics. [S0021-8979(00)69308-8]. C1 Temple Univ, Dept Phys, Philadelphia, PA 19122 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Lin, CL (reprint author), Temple Univ, Dept Phys, Philadelphia, PA 19122 USA. NR 14 TC 0 Z9 0 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6797 EP 6799 DI 10.1063/1.372845 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800295 ER PT J AU Chang, S Nakotte, H Andreev, AV Bordallo, HN Havela, L Sechovsky, V Torikachvili, MS AF Chang, S Nakotte, H Andreev, AV Bordallo, HN Havela, L Sechovsky, V Torikachvili, MS TI Magnetism in some UCo1/3T2/3Al solid solutions (T=transition metal) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID URANIUM AB We report on the magnetic properties of UCo1/3T2/3Al (T=Ru, Rh, Pt) solid solutions which form in the hexagonal ZrNiAl structure. We performed neutron diffraction and bulk magnetization studies. All three solid solutions exhibit long-range magnetic order at low temperatures. Bulk magnetization studies indicate a ferromagnetic ground state for UCo1/3Ru2/3Al, UCo1/3Rh2/3Al, and UCo1/3Pt2/3Al below 42, 41, and 27 K, respectively. At 4.2 K, the spontaneous moment ranges from similar to 0.15 mu(B)/U-atom (UCo1/3Ru2/3Al) to similar to 0.49 mu(B)/U-atom (UCo1/3Pt2/3Al). Below T-C, we find additional weak magnetic contributions in the neutron diffraction data, and our refinement is consistent with magnetic moments along the c axis. The magnitudes of the moments are in good agreement with the spontaneous moments determined from bulk studies. The results are discussed in terms of f-d hybridization, which is modified by changes in the d band occupation and preferential occupation of the transition metals within the lattice. (C) 2000 American Institute of Physics. [S0021-8979(00)94108-2]. C1 New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Acad Sci Czech Republ, Inst Phys, CZ-18040 Prague 8, Czech Republic. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Charles Univ, Dept Elect Struct, Prague 12116 2, Czech Republic. San Diego State Univ, Dept Phys, San Diego, CA 92182 USA. RP Chang, S (reprint author), New Mexico State Univ, Dept Phys, MSC 3D, Las Cruces, NM 88003 USA. RI Andreev, Alexander/B-6057-2011; Bordallo, Heloisa/I-6836-2012; Sechovsky, Vladimir/A-5256-2008 OI Bordallo, Heloisa/0000-0003-0750-0553; Sechovsky, Vladimir/0000-0003-1298-2120 NR 8 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6812 EP 6814 DI 10.1063/1.372850 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800300 ER PT J AU Kolomiets, AV Havela, L Rafaja, D Bordallo, HN Nakotte, H Yartys, VA Hauback, BC Drulis, H Iwasieczko, W DeLong, LE AF Kolomiets, AV Havela, L Rafaja, D Bordallo, HN Nakotte, H Yartys, VA Hauback, BC Drulis, H Iwasieczko, W DeLong, LE TI Magnetic properties and crystal structure of HoNiAl and UNiAl hydrides SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc AB The effect of hydrogenation on the magnetic properties and crystal structure of 4f and 5f intermetallics was studied on HoNiAlH2.0, UNiAlH2.3 and UNiAlD2.1. The incorporation of hydrogen into HoNiAl leads to a decrease of the magnetic ordering temperature from 13 to 6 K, while it increases from 19 K to values in the range 90-100 K in the UNiAl-H system. The crystal lattices of all compounds are anisotropically expanded. Moreover, the crystal symmetry is lowered to orthorhombic in HoNiAlH2.0, but remains hexagonal for UNiAlH(D)(x). Three different deuterium positions were found for both compounds. (C) 2000 American Institute of Physics. [S0021-8979(00)94208-7]. C1 Charles Univ, Dept Elect Struct, Prague 12116 2, Czech Republic. Argonne Natl Lab, Argonne, IL 60439 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Inst Energy Technol, N-2027 Kjeller, Norway. Polish Acad Sci, W Trzebiatowski Inst Low Temp & Struct Res, PL-50950 Wroclaw, Poland. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. RP Kolomiets, AV (reprint author), Charles Univ, Dept Elect Struct, Ke Karlovu 5, Prague 12116 2, Czech Republic. RI Bordallo, Heloisa/I-6836-2012; OI Bordallo, Heloisa/0000-0003-0750-0553; Rafaja, David/0000-0003-2411-7425 NR 16 TC 15 Z9 15 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6815 EP 6817 DI 10.1063/1.372851 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800301 ER PT J AU Goremychkin, EA Osborn, R AF Goremychkin, EA Osborn, R TI Crystal field excitations in YbT2Si2 (T = Fe, Co, Ni) SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 44th Annual Conference on Magnetism and Magnetic Materials CY NOV 15-18, 1999 CL SAN JOSE, CALIFORNIA SP Amer Inst Phys, Magnet Soc Inst Elect & Electr Engineers, Minerals Met & Mat Soc, Amer Soc Testing & Mat, USN Off Res, Amer Ceram Soc, Amer Phys Soc ID NEUTRON-SCATTERING AB The results of an inelastic neutron scattering investigation of the crystal field potential of YbT2Si2 (T = Ni, Co, Fe) are reported. We have observed well-defined inelastic peaks due to crystal field transitions for all three compounds. By performing a profile refinement of the measured spectra, we have determined the parameters of the crystal field Hamiltonian for YbCo2Si2 and YbNi2Si2. (C) 2000 American Institute of Physics. [S0021-8979(00)69608-1]. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Goremychkin, EA (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Osborn, Raymond/E-8676-2011 OI Osborn, Raymond/0000-0001-9565-3140 NR 11 TC 12 Z9 12 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 2000 VL 87 IS 9 BP 6818 EP 6820 DI 10.1063/1.372852 PN 3 PG 3 WC Physics, Applied SC Physics GA 308TK UT WOS:000086728800302 ER PT J AU Stephens, GL McCoy, RF McCoy, RB Gabriel, P Partain, PT Miller, SD Love, SP AF Stephens, GL McCoy, RF McCoy, RB Gabriel, P Partain, PT Miller, SD Love, SP TI A multipurpose scanning spectral polarimeter (SSP): Instrument description and sample results SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article ID ATMOSPHERIC RADIATION; SOLAR-RADIATION; ABSORPTION; CLOUDS AB This paper describes the design and characteristics of a scanning spectral polarimeter designed to measure spectral radiances and fluxes in the range between 0.4 and 4.0 mu m. The instrument characteristics are described, and the procedures to calibrate the unpolarized radiances and fluxes in the spectral range from 0.4 to 1.1 mu m are discussed along with detailed error analyses of this calibration. The accuracy of the radiance calibration was determined to be approximately 3%. The calibration of fluxes based on two different procedures is estimated to be accurate to 3%-6%. Detailed calibration of fluxes was performed using a standard lamp that is not an isotropic source. For this type of calibration the angular response of the flux channel deviates from a pure cosine function at wavelengths longer than 0.74 mu m, thus forming a frontal lobe. A less detailed calibration using a 40-in. integrated sphere was also performed. In that case the light source is isotropic and the frontal lobe does not appear. Calibration factors are derived by combining data from bath calibration procedures. A comparison with spectral flux measurements obtained from different instruments with different angular response properties is presented with agreement that is within the quoted calibration accuracy. Measurements obtained from two different aircraft flights are presented to illustrate the types of application of the data. Data analyses shows that the reflected (unpolarized) fluxes measured above a cirrus cloud can be reasonably matched to modeled fluxes using optical properties retrieved from the measured (unpolarized) radiances. C1 Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. Univ Calif Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Los Alamos, NM USA. RP Stephens, GL (reprint author), Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. NR 14 TC 4 Z9 4 U1 0 U2 2 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD MAY PY 2000 VL 17 IS 5 BP 616 EP 627 DI 10.1175/1520-0426(2000)017<0616:AMSSPS>2.0.CO;2 PG 12 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 319ET UT WOS:000087329100003 ER PT J AU Keim, P Price, LB Klevytska, AM Smith, KL Schupp, JM Okinaka, R Jackson, PJ Hugh-Jones, ME AF Keim, P Price, LB Klevytska, AM Smith, KL Schupp, JM Okinaka, R Jackson, PJ Hugh-Jones, ME TI Multiple-locus variable-number tandem repeat analysis reveals genetic relationships within Bacillus anthracis SO JOURNAL OF BACTERIOLOGY LA English DT Article ID DNA REPEATS; DIVERSITY; SEQUENCE; IDENTIFICATION; VARIABILITY; STRAINS; GENOMES; PCR AB Bacillus anthracis is one of the most genetically homogeneous pathogens described, making strain discrimination particularly difficult. In this paper, we present a novel molecular typing system based on rapidly evolving variable-number tandem repeat (VNTR) loci. Multiple-locus VNTR analysis (MLVA) uses the combined power of multiple alleles at several marker loci. In our system, fluorescently labeled PCR primers are used to produce PCR amplification products from eight VNTR regions in the B. anthracis genome. These are detected and their sizes are determined using an ABI377 automated DNA sequencer. Five of these eight loci were discovered by sequence characterization of molecular markers (vrrC(1), vrrC(2), vrrB(1), vrrB(2), and CG3), two mere discovered by searching complete plasmid nucleotide sequences (pXO1-aat and pXO2-at), and one was known previously (vrrA). MLVA characterization of 426 B. anthracis isolates identified 89 distinct genotypes. VNTR markers frequently identified multiple alleles (from two to nine), with Nei's diversity values between 0.3 and 0.8. Unweighted pair-group method arithmetic average cluster analysis identified six genetically distinct groups that appear to be derived from clones. Some of these clones show worldwide distribution, while others are restricted to particular geographic regions. Human commerce doubtlessly has contributed to the dispersal of particular clones in ancient and modern times. C1 No Arizona Univ, Dept Biol Sci, Flagstaff, AZ 86011 USA. Louisiana State Univ, Sch Vet Med, Dept Epidemiol & Community Hlth, Baton Rouge, LA 70803 USA. Univ Calif Los Alamos Natl Lab, Environm Mol Biol Grp, Los Alamos, NM 87545 USA. RP Keim, P (reprint author), No Arizona Univ, Dept Biol Sci, Box 5640, Flagstaff, AZ 86011 USA. RI Keim, Paul/A-2269-2010 FU NIGMS NIH HHS [R01 GM060795, R01GM60795] NR 27 TC 481 Z9 530 U1 1 U2 19 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD MAY PY 2000 VL 182 IS 10 BP 2928 EP 2936 DI 10.1128/JB.182.10.2928-2936.2000 PG 9 WC Microbiology SC Microbiology GA 309JE UT WOS:000086764100033 PM 10781564 ER PT J AU Ridley, MK Xiao, CB Palmer, DA Wesolowski, DJ AF Ridley, MK Xiao, CB Palmer, DA Wesolowski, DJ TI Thermodynamic properties of the ionization of morpholine as a function of temperature and ionic strength SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID AQUEOUS SODIUM TRIFLUOROMETHANESULFONATE; POTENTIOMETRIC DETERMINATION; DISSOCIATION QUOTIENTS; ASSOCIATION QUOTIENTS; MALONATE COMPLEXATION; ALUMINUM SPECIATION; ACETATE COMPLEXES; OXALIC-ACID; NACL MEDIA; CHLORIDE AB A hydrogen-electrode concentration cell was used to monitor pH in a study of morpholine ionization in aqueous solutions to temperatures of 290 degrees C and to ionic strengths of 1 m, maintained with either sodium trifluoromethanesulfonate or sodium chloride. The resulting hydrolysis quotients were combined with values from two previous potentiometric investigations of this reaction, as well as existing heat capacity and apparent molar volume data, to provide a global fitting equation. The computed thermodynamic parameters for the acid dissociation of the morpholinium ion at 25 degrees C and infinite dilution are log K = (-8.491 +/- 0.003); Delta H = (39 +/- 1) kJ.mol(-1); Delta S = (-31 +/- 1) J.K-1 mol(-1); Delta C-p = (40 +/- 7) J.K-1.mol(-1); and Delta V = (3 +/- 1) cm(3).mol(-1). At low ionic strengths, including values at infinite dilution, the log Q data were found to be near linear with respect to the reciprocal temperature in Kelvin over the measured temperature range of 0 degrees C to 300 degrees C. C1 Texas Tech Univ, Dept Geosci, Lubbock, TX 79409 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Ridley, MK (reprint author), Texas Tech Univ, Dept Geosci, POB 41053, Lubbock, TX 79409 USA. NR 27 TC 10 Z9 11 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD MAY-JUN PY 2000 VL 45 IS 3 BP 502 EP 507 DI 10.1021/je9903146 PG 6 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 313YG UT WOS:000087026800021 ER PT J AU Houk, RS AF Houk, RS TI Inductively coupled plasma-mass spectrometry and the European discovery of America SO JOURNAL OF CHEMICAL EDUCATION LA English DT Article; Proceedings Paper CT 10th Annual James L Waters Symposium at Pittcon CY MAR, 1999 CL PTIISBURGH, PENNSYLVANIA ID ICP-MS; TRACE-ELEMENTS; MATRIX; LENS; DENSITY C1 Iowa State Univ, Dept Chem, Ames Lab, US DOE, Ames, IA 50011 USA. RP Houk, RS (reprint author), Iowa State Univ, Dept Chem, Ames Lab, US DOE, Ames, IA 50011 USA. NR 36 TC 9 Z9 9 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD MAY PY 2000 VL 77 IS 5 BP 598 EP 607 PG 10 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA 303RX UT WOS:000086439000012 ER PT J AU Curtiss, LA Raghavachari, K Redfern, PC Pople, JA AF Curtiss, LA Raghavachari, K Redfern, PC Pople, JA TI Assessment of Gaussian-3 and density functional theories for a larger experimental test set SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID QUADRATIC CONFIGURATION-INTERACTION; CORRELATION ENERGIES; PERTURBATION-THEORY; BOND-ENERGIES; PARAMETER-X; FIRST-ROW; PCI-X; THERMOCHEMISTRY; COMPUTATION; GEOMETRIES AB The G2/97 test set [J. Chem. Phys. 106, 1063 (1997)] for assessing quantum chemical methods used to predict thermochemical data is expanded to include 75 additional enthalpies of formation of larger molecules. This new set, referred to as the G3/99 test set, includes enthalpies of formation, ionization potentials, electron affinities, and proton affinities in the G2/97 set and 75 new enthalpies of formation. The total number of energies in the G3/99 set is 376. Overall, G3 theory has a mean absolute deviation of 1.07 kcal/mol for the G3/99 test set and does about as well for the new hydrocarbons and substituted hydrocarbons as it does for those in the G2/97 test. However, G3 theory has large deviations for several of the new nonhydrogen systems in the G3/99 test set such as SF6 and PF5. Part of the source of error is traced to the inadequate geometries used in G3 theory for these molecules. Other variations of G3 theory are also assessed such as G3(MP2), G3(MP3), and the versions of G3 theory using scaled energy terms instead of the higher level correction. These variations also do well for the larger hydrocarbons and substituted hydrocarbons, but fail for the same nonhydrogen systems as G3 theory. The density functional methods assessed in this study, including the hybrid B3LYP method, all have much larger deviations from experiment for the new enthalpies of formation in the expanded test set; the mean absolute deviation more than doubles compared to that for the enthalpies in the G2/97 test set. This is due to a cumulative effect of the errors in the larger molecules in the density functional methods. (C) 2000 American Institute of Physics. [S0021-9606(00)30815-7]. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. RP Curtiss, LA (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 43 TC 613 Z9 617 U1 3 U2 36 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 2000 VL 112 IS 17 BP 7374 EP 7383 DI 10.1063/1.481336 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 305DH UT WOS:000086523800012 ER PT J AU Frink, LJD Thompson, A Salinger, AG AF Frink, LJD Thompson, A Salinger, AG TI Applying molecular theory to steady-state diffusing systems SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID GRADIENT-DRIVEN DIFFUSION; DYNAMICS SIMULATION; SELF-DIFFUSION; TRANSPORT; FLUIDS; MEMBRANE; EQUILIBRIUM; TRANSITION; SILICALITE; MICROPORES AB Predicting the properties of nonequilibrium systems from molecular simulations is a growing area of interest. One important class of problems involves steady-state diffusion. To study these cases, a grand canonical molecular dynamics approach has been developed by Heffelfinger and van Swol [J. Chem. Phys. 101, 5274 (1994)]. With this method, the flux of particles, the chemical potential gradients, and density gradients can all be measured in the simulation. In this paper, we present a complementary approach that couples a nonlocal density functional theory (DFT) with a transport equation describing steady-state flux of the particles. We compare transport-DFT predictions to GCMD results for a variety of ideal (color diffusion), and nonideal (uphill diffusion and convective transport) systems. In all cases, excellent agreement between transport-DFT and GCMD calculations is obtained with diffusion coefficients that are invariant with respect to density and external fields. (C) 2000 American Institute of Physics. [S0021-9606(00)50315-8]. C1 Sandia Natl Labs, Dept Computat Biol & Mat Technol, Albuquerque, NM 87185 USA. Sandia Natl Labs, Dept Parallel Computat Sci, Albuquerque, NM 87185 USA. RP Frink, LJD (reprint author), Sandia Natl Labs, Dept Computat Biol & Mat Technol, POB 5800, Albuquerque, NM 87185 USA. NR 32 TC 17 Z9 17 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 2000 VL 112 IS 17 BP 7564 EP 7571 DI 10.1063/1.481376 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 305DH UT WOS:000086523800032 ER PT J AU Fenter, P Cheng, L Rihs, S Machesky, M Bedzyk, MJ Sturchio, NC AF Fenter, P Cheng, L Rihs, S Machesky, M Bedzyk, MJ Sturchio, NC TI Electrical double-layer structure at the rutile-water interface as observed in situ with small-period X-ray standing waves SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE electrical double layer; X-ray standing waves; mineral-fluid interface; rutile; Sr2+ and Rb+ adsorption ID METAL-OXIDE SURFACES; INCIDENCE XAFS SPECTROSCOPY; DIFFUSE-DOUBLE-LAYER; COUNTERION DISTRIBUTION; ION ADSORPTION; 250-DEGREES-C; IDENTIFICATION; SCATTERING; MICELLES; SORPTION AB X-Ray standing wave (XSW) measurements were made of Rb and Sr adsorbed from aqueous solutions at the rutile (110)-water interface. These experiments were performed to address the extent to which direct measurements of electrical double-layer structure are possible. The experimental results show that the Bragg XSW technique, using small-period standing waves generated by Bragg diffraction from the substrate, can precisely measure ion locations within the condensed layer and the in situ partitioning of ions between the condensed and diffuse layers. Differences in condensed layer ion positions were observed for Sr ions (measured in situ) as compared with Rb ions (in situ) and also for Sr ions (ex situ). An additional constraint on the ex situ Sr site geometry was provided by polarization-dependent surface EXAFS measurements. Such measurements can provide important constraints for the development and verification of electrical double-layer theory especially as applied to ion adsorption at the solid-water interface. (C) 2000 Academic Press. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Northwestern Univ, Inst Environm Catalysis, Evanston, IL 60208 USA. Illinois State Water Survey, Champaign, IL 61820 USA. RP Fenter, P (reprint author), Argonne Natl Lab, ER-203,9700 S Cass Ave, Argonne, IL 60439 USA. RI Bedzyk, Michael/B-7503-2009; Cheng, Likwan/C-1436-2013; Bedzyk, Michael/K-6903-2013 NR 37 TC 79 Z9 79 U1 4 U2 18 PU ACADEMIC PRESS INC 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 MAY 1 PY 2000 VL 225 IS 1 BP 154 EP 165 DI 10.1006/jcis.2000.6756 PG 12 WC Chemistry, Physical SC Chemistry GA 309UC UT WOS:000086786800019 ER PT J AU Tuzun, RE Noid, DW Sumpter, BG AF Tuzun, RE Noid, DW Sumpter, BG TI Computation of internal coordinates, derivatives, and gradient expressions: Torsion and improper torsion SO JOURNAL OF COMPUTATIONAL CHEMISTRY LA English DT Article DE gradient; molecular dynamics; molecular mechanics; internal coordinate quantum Monte Carlo ID MOLECULAR-DYNAMICS; ENERGY; SIMULATIONS; FORCE AB Laplacians and gradient dot products are required for the recently developed internal coordinate quantum Monte Carlo method. New formulas are presented for these quantities for torsion and improper torsion angles. The Laplacians can also be used to economize calculation of sets of second derivatives used in molecular mechanics and other methods. Formulas for torsion angle gradient dot products and Laplacians, and completely new formulas for improper torsion, are presented In addition, calculations of cos tau and sin tau, some suitable for energy subroutines and others for force subroutines, are shown. Finally, in a related development, several sets of conditions for three atom Linearity or four atom planarity involving internal coordinate derivatives are reported. (C) 2000 John Wiley & Sons, Inc. C1 SUNY Coll Brockport, Computat Sci Program, Brockport, NY 14420 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Tuzun, RE (reprint author), SUNY Coll Brockport, Computat Sci Program, Brockport, NY 14420 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 14 TC 5 Z9 5 U1 1 U2 15 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0192-8651 J9 J COMPUT CHEM JI J. Comput. Chem. PD MAY PY 2000 VL 21 IS 7 BP 553 EP 561 DI 10.1002/(SICI)1096-987X(200005)21:7<553::AID-JCC4>3.3.CO;2-T PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 307WP UT WOS:000086677400004 ER PT J AU Canning, A Wang, LW Williamson, A Zunger, A AF Canning, A Wang, LW Williamson, A Zunger, A TI Parallel empirical pseudopotential electronic structure calculations for million atom systems SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE electronic structure; density functional theory; conjugate gradients; pseudopotential; quantum dots ID SEMICONDUCTOR QUANTUM DOTS; TOTAL-ENERGY CALCULATIONS; OPTICAL-PROPERTIES; BAND-GAPS; ALLOYS; POTENTIALS; DEPENDENCE; GAASN AB We present a parallel implementation of the previously developed folded spectrum method for empirical pseudopotential electronic structure calculations. With the parallel implementation we can calculate a small number of electronic states for systems of up to one million atoms. A plane-wave basis is used to expand the wavefunctions in the same way as is commonly used in ab initio calculations, but the potential is a fixed external potential generated using atomistic empirical pseudopotentials. Two techniques allow the calculation to scale to million atom systems. First, the previously developed folded spectrum method allows us to calculate directly a few electronic states of interest around the gap. This makes the scaling of the calculation O (N) for an N atom system and a fixed number of electronic states. Second, we have now developed an efficient parallel implementation of the algorithm that scales up to hundreds of processors, giving us the memory and computer power to simulate one million atoms. The program's performance is demonstrated for many large semiconductor nanostructure systems. (C) 2000 Academic Press. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. RI Zunger, Alex/A-6733-2013 NR 31 TC 78 Z9 78 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 0021-9991 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAY 1 PY 2000 VL 160 IS 1 BP 29 EP 41 DI 10.1006/jcph.2000.6440 PG 13 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 309RF UT WOS:000086782500002 ER PT J AU Dukowicz, JK Baumgardner, JR AF Dukowicz, JK Baumgardner, JR TI Incremental remapping as a transport/advection algorithm SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE remapping; transport; advection; semi-lagrange ID ADVECTION; SCHEMES AB There are two fundamentally different strategies for solving the standard transport or continuity equation, corresponding to whether it is expressed as a partial differential equation or as an integral statement of conservation. The more common approach is to discretize the partial differential equation and to march the solution forward in time. The alternative method is to project cell volumes along Lagrangian trajectories as far forward or backward in time as desired. and then to remap the resulting density distribution onto some target mesh. This latter approach is known as remapping. Remapping has many advantages, not the least of which is that the rime step is limited only by accuracy considerations, but it tends to be expensive and complex. In this paper we show that if the time step is made sufficiently short such that trajectories are confined to the nearest neighbor cells, then the remapping may be written as a flux-form transport algorithm, and it becomes nearly as simple and efficient as standard transport schemes. The resulting method, called incremental remapping, retains most of the advantages of general remapping. These include: (a) geometric basis for transport, (b) compatibility of associated tracts transport with simple tracer advection, i.e., retention of tracer monotonicity properties, and (c) efficient handling of multiple tracers since each additional tracer adds only a relatively small incremental cost. C1 Los Alamos Natl Lab, Div Theoret, Grp T3, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Theoret, Grp T3, Mail Stop B216, Los Alamos, NM 87545 USA. EM Duk@lanl.gov; Baumgardner@lanl.gov NR 18 TC 77 Z9 83 U1 0 U2 6 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAY 1 PY 2000 VL 160 IS 1 BP 318 EP 335 DI 10.1006/jcph.2000.6465 PG 18 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 309RF UT WOS:000086782500014 ER PT J AU Chilakapati, A Yabusaki, S Szecsody, J MacEvoy, W AF Chilakapati, A Yabusaki, S Szecsody, J MacEvoy, W TI Groundwater flow, multicomponent transport and biogeochemistry: development and application of a coupled process model SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article DE groundwater modeling; reactive transport; biogeochemistry; mixed kinetic-equilibrium reactions; particle tracking ID CO(II/III)EDTA REACTIVE TRANSPORT; CARBON-TETRACHLORIDE; SOLUTE TRANSPORT; NUMERICAL-MODEL; OXIDE SURFACE; POROUS-MEDIA; REDUCTION; IRON; CHROMATOGRAPHY; HETEROGENEITY AB A research tool for modeling the reactive flow and transport of groundwater contaminants in multiple dimensions is presented, Arbitrarily complex coupled kinetic-equilibrium heterogeneous reaction networks, automatic code generation, transfer-function based solutions, parameter estimation, high-resolution methods for advection, and robust solvers for the mixed kinetic-equilibrium chemistry are some of the features of reactive flow and transport (RAFT) that make it a versatile research tool in the modeling of a wide variety of laboratory and field experiments. The treatment of reactions is quite general so that RAFT can be used to model biological, adsorption/desorption, complexation, and mineral dissolution/precipitation reactions among others. The integrated framework involving automated code generation and parameter estimation allows for the development, characterization, and evaluation of mechanistic process models, The model is described and used to solve a problem in competitive adsorption that illustrates some of these features. The model is also used to study the development of an in situ Fe(II)-zone by encouraging the growth of an iron-reducing bacterium with lactate as the electron donor. Such redox barriers are effective in sequestering groundwater contaminants such as chromate and TCE. Published by Elsevier Science B.V. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Mesa State Coll, Grand Junction, CO 81501 USA. RP Chilakapati, A (reprint author), Pacific NW Natl Lab, POB 999,Mail Stop K9-36, Richland, WA 99352 USA. NR 53 TC 33 Z9 33 U1 3 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD MAY PY 2000 VL 43 IS 3-4 BP 303 EP 325 DI 10.1016/S0169-7722(99)00107-2 PG 23 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 312MQ UT WOS:000086947400005 ER PT J AU Muramatsu, Y Ueno, Y Hayashi, T Grush, MM Gullikson, EM Perera, RCC AF Muramatsu, Y Ueno, Y Hayashi, T Grush, MM Gullikson, EM Perera, RCC TI Soft X-ray emission and absorption spectroscopy of hydrofullerene SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article DE x-ray spectra; synchrotron radiation; hydrofullerene; DV-X alpha molecular orbital calculations; electronic structure ID C60H36; C-60; HYDROGEN AB High-resolution soft X-ray emission and absorption spectra in the C K region of hydrofullerene, which probably consists mainly of C60H36, were measured using highly brilliant synchrotron radiation to identify its molecular structure and electronic structure. Comparison with the C2p-DOS spectra, calculated by discrete variational (DV) X alpha molecular orbital calculations, of three possible C60H36 isomers, showed that the measured X-ray spectra approximately agreed with the calculated C2p-DOS spectra of the T-symmetry isomer. The X-ray spectral features were explained by the electronic structure hybridized between the sp(2) and sp(3) carbon atoms of the T-symmetry C60H36. (C) 2000 Elsevier Science B.V. All rights reserved. C1 NTT, Lifestyle & Environm Res Labs, Tokyo 1808585, Japan. Univ Tennessee, Knoxville, TN 37996 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Muramatsu, Y (reprint author), NTT, Lifestyle & Environm Res Labs, Tokyo 1808585, Japan. RI Ueno, Yuko/H-5651-2012 NR 21 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD MAY PY 2000 VL 107 IS 2 BP 177 EP 184 DI 10.1016/S0368-2048(00)00101-8 PG 8 WC Spectroscopy SC Spectroscopy GA 312NX UT WOS:000086950300009 ER PT J AU McComas, DJ Barraclough, BL Funsten, HO Gosling, JT Santiago-Munoz, E Skoug, RM Goldstein, BE Neugebauer, M Riley, P Balogh, A AF McComas, DJ Barraclough, BL Funsten, HO Gosling, JT Santiago-Munoz, E Skoug, RM Goldstein, BE Neugebauer, M Riley, P Balogh, A TI Solar wind observations over Ulysses' first full polar orbit SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID STREAMER BELT; PLASMA; HELIUM; SPEED; LATITUDES; MINIMUM AB This study examines solar wind plasma and magnetic field observations from Ulysses' first full polar orbit in order to characterize the high-latitude solar wind under conditions of decreasing and low solar activity. By comparing observations taken over nearly all heliolatitudes and two different intervals covering the same radial distances, we are able to separate the radial and latitudinal variations in the solar wind. We find that once the radial gradients are removed, none of the high-latitude solar wind parameters show much latitudinal variation, indicating that the solar wind emanating from the polar coronal holes is extremely uniform. In addition, by examining nearly 6 years of data starting in the declining phase of the last solar cycle and extending through the most recent solar minimum, we are able to address hemispheric asymmetries in the observations. We find that these asymmetries are most likely driven by differences in the solar wind source over the solar cycle and indicate that Inert energy goes into the polar solar wind during the declining phase of the solar cycle than around minimum. Because the mass flux is larger in the declining phase while the speeds are very similar, we conclude that this energy is introduced at an altitude below the solar wind acceleration critical point. Finally, we provide details of the statistics of over 20 solar wind parameters so that upcoming observations from Ulysses' second polar orbit, during much more active times on the Sun, can be readily compared to the quieter first orbit results. C1 Los Alamos Natl Lab, Los Alamos, NM USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Sci Applicat Int Corp, San Diego, CA 92121 USA. Univ London Imperial Coll Sci Technol & Med, Dept Phys, London SW7 2AZ, England. RP McComas, DJ (reprint author), Los Alamos Natl Lab, MS-D466, Los Alamos, NM USA. RI Funsten, Herbert/A-5702-2015 OI Funsten, Herbert/0000-0002-6817-1039 NR 36 TC 292 Z9 294 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 2000 VL 105 IS A5 BP 10419 EP 10433 DI 10.1029/1999JA000383 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309AQ UT WOS:000086745400020 ER PT J AU Kazimura, Y Gary, SP Li, H Sakai, JI AF Kazimura, Y Gary, SP Li, H Sakai, JI TI Electromagnetic fluctuations near the electron plasma frequency from an electron/electron instability SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID COMPETING PROCESSES; Z-MODE; BEAM; SIMULATIONS; EMISSIONS; WHISTLER; DRIVEN AB Enhanced electromagnetic fluctuations near the electron plasma frequency omega(e) are observed in the auroral and polar regions of the terrestrial magnetosphere; until recently, their origin has not been understood. Linear Vlasov theory and a particle-in-cell simulation with a two-dimensional fully relativistic electromagnetic code have been carried out for an electron/electron instability in a homogeneous, collisionless, mag magnetized plasma model under the condition omega(e)/\Omega(e)\ < 1 where Omega(e) is the electron cyclotron frequency. At propagation parallel to the background magnetic field the instability is strictly electrostatic, but at oblique propagation significant electromagnetic fluctuations are also excited. The simulation reproduces the following essential features of the observed plasma frequency fluctuations: (1) narrowband frequencies near omega(e), (2) relatively large electric fields (delta E/delta B much greater than 1), and (3) episodes of both right-hand and left-hand polarization. This polarization result is new and has not been published before. Furthermore, the present theory and simulation show that the right-hand polarized fluctuations are on a short-wavelength beam mode and are excited by linear instability,growth; the left-hand fluctuations are at relatively long wavelengths and are apparently driven by nonlinear processes. C1 Toyama Univ, Lab Plasma Astrophys, Toyama 930, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kazimura, Y (reprint author), Toyama Univ, Lab Plasma Astrophys, Toyama 930, Japan. NR 17 TC 2 Z9 2 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 2000 VL 105 IS A5 BP 10537 EP 10542 DI 10.1029/1999JA000410 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309AQ UT WOS:000086745400030 ER PT J AU Gary, SP Winske, D Hesse, M AF Gary, SP Winske, D Hesse, M TI Electron temperature anisotropy instabilities: Computer simulations SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID AURORAL KILOMETRIC RADIATION; WHISTLER-MODE WAVES; POLAR-CAP; DE-1 OBSERVATIONS; RADIO EMISSIONS; PLASMA; MAGNETOSPHERE; GENERATION; DAYSIDE; REGION AB An electron temperature anisotropy T-perpendicular to e/T-parallel to e > 1 leads to excitation of three distinct modes, the whistler, the electrostatic, and the Z-mode instabilities, in collisionless plasmas at frequencies below the electron cyclotron frequency \Omega(e)\. (Here perpendicular and parallel subscripts denote directions relative to the background magnetic field.) Two-and-one-half-dimensional particle-in-cell simulations are used to study the nonlinear consequences of the growth of these modes in homogeneous plasmas with omega(e) similar to \Omega(e)\, where omega(e) is the electron plasma frequency. The simulations show that wave-particle scattering by enhanced fluctuations from the whistler and electrostatic anisotropy instabilities imposes a beta-dependent upper bound on the electron temperature anisotropy at beta(parallel to e) less than or equal to 0.10 The simulations also demonstrate that the maximum value of the dimensionless fluctuating magnetic fields increases with PII, and that at sufficiently low beta the electrostatic instability leads to non-Maxwellian suprathermal enhancements on the reduced electron velocity distribution f(e)(nu(parallel to)). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Gary, SP (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. RI Hesse, Michael/D-2031-2012 NR 29 TC 29 Z9 30 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAY 1 PY 2000 VL 105 IS A5 BP 10751 EP 10759 DI 10.1029/1999JA000322 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 309AQ UT WOS:000086745400047 ER PT J AU Lacy, DA Wang, ZE Symula, DJ McArthur, CJ Rubin, EM Frazer, KA Locksley, RM AF Lacy, DA Wang, ZE Symula, DJ McArthur, CJ Rubin, EM Frazer, KA Locksley, RM TI Faithful expression of the human 5q31 cytokine cluster in transgenic mice SO JOURNAL OF IMMUNOLOGY LA English DT Article ID T-CELLS; TH2 CELLS; GENE; ASTHMA; IL-4; STAT6; INTERLEUKIN-4; ACTIVATION; SUFFICIENT; RESPONSES AB Interleukins -4, -5, and -13, cardinal cytokines produced by Th2 cells, are coordinately expressed and clustered in 150-kb syntenic regions on mouse chromosome 11 and human chromosome 5q31. We analyzed two sets of human yeast artificial chromosome transgenic mice that contained the 5q31 cytokines to assess whether conserved sequences required for their-coordinate and cell-specific regulation are contained within the cytokine cluster itself. Human IL-4, IL-13, and IL-5 were expressed under Th2, but not Th1, conditions in vitro. Each of these cytokines was produced during infection with Nippostrongylus brasiliensis, a Th2-inducing stimulus, and human IL-4 was generated after activation of NK T cells in vivo. Consistently fewer cells produced the endogenous mouse cytokines in transgenic than in control mice, suggesting competition for stable expression between the mouse and human genes. These data imply the existence of both conserved trans-activating factors and cis-regulatory elements that underlie the coordinate expression and lineage specificity of the type 2 cytokine genes in lymphocytes, The Journal of Immunology, 2000, 164: 4569-4574. C1 Univ Calif San Francisco, Howard Hughes Med Inst, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Med, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Immunol Microbiol, San Francisco, CA 94143 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Genome Sci, Berkeley, CA 94720 USA. RP Locksley, RM (reprint author), Univ Calif San Francisco, Howard Hughes Med Inst, Box 0654,C-443,521 Parnassus Ave, San Francisco, CA 94143 USA. FU NHLBI NIH HHS [HL56385]; NIAID NIH HHS [AI30663] NR 35 TC 14 Z9 14 U1 0 U2 0 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD MAY 1 PY 2000 VL 164 IS 9 BP 4569 EP 4574 PG 6 WC Immunology SC Immunology GA 306XQ UT WOS:000086624300019 PM 10779759 ER PT J AU Liekhus, KJ Zlochower, IA Cashdollar, KL Djordjevic, SM Loehr, CA AF Liekhus, KJ Zlochower, IA Cashdollar, KL Djordjevic, SM Loehr, CA TI Flammability of gas mixtures containing volatile organic compounds and hydrogen SO JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES LA English DT Article DE flammability; volatile organic compounds; hydrogen; test-chamber; prediction AB An experimental program was conducted to evaluate the accuracy of some current methods for predicting the flammability of gas mixtures containing hydrogen and flammable or nonflammable volatile organic compounds (VOCs) in air. The specific VOCs tested were toluene, 1,2-dichloroethane, 2-butanone, and carbon tetrachloride. The lower flammability limits (LFLs) of gas mixtures containing equal molar quantities of the components were determined in a 19.4-1 laboratory flammability chamber using a strong spark ignition source and a pressure criterion for flammability. All but one of the LFL values for the individual components were in agreement with earlier Literature values. However, the LFL of 1,2-dichloroethane was found to be significantly lower than the range of values reported for previous determinations in smaller chambers. Two methods for calculating the LFL of mixtures were considered. The Group Factor (atomic) Contribution Method was determined to be generally more accurate than the LeChatelier Method for estimating the LFL of the gas mixtures reported here, although the LeChatelier Method was usually more conservative. The Group Factor Method predicted higher values (nonconservative) for the LFLs of several mixtures than were experimentally measured. For the case of a mixture of hydrogen and carbon tetrachloride, the Group Method estimation of the LFL was seriously in error. (C) 2000 Published by Elsevier Science Ltd. All rights reserved. C1 NIOSH, Pittsburgh Res Lab, Pittsburgh, PA 15236 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Benchmark Environm, Albuquerque, NM 87110 USA. RP Zlochower, IA (reprint author), NIOSH, Pittsburgh Res Lab, Pittsburgh, PA 15236 USA. NR 14 TC 35 Z9 36 U1 2 U2 12 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0950-4230 J9 J LOSS PREVENT PROC JI J. Loss Prev. Process Ind. PD MAY-OCT PY 2000 VL 13 IS 3-5 SI SI BP 377 EP 384 DI 10.1016/S0950-4230(99)00034-0 PG 8 WC Engineering, Chemical SC Engineering GA 309TK UT WOS:000086785200020 ER PT J AU Klintenberg, M Derenzo, SE Weber, MJ AF Klintenberg, M Derenzo, SE Weber, MJ TI First-principles calculations of hole trapping and transport: Effects on scintillator luminescence SO JOURNAL OF LUMINESCENCE LA English DT Article; Proceedings Paper CT International Conference on Luminescence and Optical Spectroscopy of Condensed Matter CY AUG 23-27, 1999 CL OSAKA, JAPAN SP Sci Council Japan, Phys Soc Japan, Chem Soc Japan, Japan Soc Appl Phys, Int Union Pure & Appl Phys, Commemorative Assoc Japan World Exposit, Osaka Convent Bureau, Asahi Glass Fdn, Inoue Fdn Sci, Japan Legislat Soc Fdn, Kansai Res Fdn Tech Promot, Murata Sci Fdn, Nippon Sheet Glass Fdn Mat Sci & Engn, Novaltis Fdn Japan Promot Sci, Ogasawara Fdn Promot Sci & Engn DE hole trapping; hole transport; scintillator luminescence; cluster calculations AB An ab initio molecular orbital program is applied to clusters to compute energies and electron densities that describe the formation and transport of holes produced by ionizing radiation and their effects on luminescence of inorganic scintillator crystals. The resulting electron density plots for CsI show that a relaxed hole is shared equally by two bound I atoms (the classic V-k center). The calculated energy barrier for motion of the self-trapped hole is in excellent agreement with that expected from experimental measurements of the temperature dependence of the slow scintillation rise time of Tl-activated CsI. For CaF2 initial V-k center formation is again predicted. The calculated energy barrier against hole migration is in reasonable agreement with the experimental value, however the scintillation rise time of Eu2+-activated CaF2 is very fast. In this case the Eu2+ activator promptly captures a hole before it can become self-trapped, (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Klintenberg, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 55-121, Berkeley, CA 94720 USA. NR 8 TC 3 Z9 3 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 J9 J LUMIN JI J. Lumines. PD MAY PY 2000 VL 87-9 BP 546 EP 548 DI 10.1016/S0022-2313(99)00286-0 PG 3 WC Optics SC Optics GA 310GK UT WOS:000086818000154 ER PT J AU Weber, MJ Derenzo, SE Moses, WW AF Weber, MJ Derenzo, SE Moses, WW TI Measurements of ultrafast scintillation rise times: evidence of energy transfer mechanisms SO JOURNAL OF LUMINESCENCE LA English DT Article; Proceedings Paper CT International Conference on Luminescence and Optical Spectroscopy of Condensed Matter CY AUG 23-27, 1999 CL OSAKA, JAPAN SP Sci Council Japan, Phys Soc Japan, Chem Soc Japan, Japan Soc Appl Phys, Int Union Pure & Appl Phys, Commemorative Assoc Japan World Exposit, Osaka Convent Bureau, Asahi Glass Fdn, Inoue Fdn Sci, Japan Legislat Soc Fdn, Kansai Res Fdn Tech Promot, Murata Sci Fdn, Nippon Sheet Glass Fdn Mat Sci & Engn, Novaltis Fdn Japan Promot Sci, Ogasawara Fdn Promot Sci & Engn DE scintillation processes; ultrafast rise-time measurements; X-ray-excited luminescence AB The physical processes associated with scintillation growth and decay are investigated using ultrafast measurements of luminescence following pulsed X-ray excitation. Rise times with a time resolution of similar to 30 ps have been measured for several intrinsic and activated crystalline and amorphous materials at room temperature. Rise times of excitonic emission from CsI, CaF2, Y2SiO5, Y3Al5O12, Bi4Ge3O12, CeF3,and fused silica were less than our system response time, thus demonstrating very fast ( < 30 ps) exciton formation. Rapid rise times of < 100 ps were observed for CdS : Te2-, CaF2 : Eu2+, and Ce3+-activated aluminate, berate, phosphate, and berate crystals and silica and silicate glasses and are characteristic of prompt capture of holes at the activator site followed by electron capture. (Some Ce3+-activated materials also exhibit a slower rise-rime component(s) due to exciton-cerium transfer.) in contrast, CsI(Tl), CsI(Na), and NaI(Tl) have scintillation rise times of > 10 ns indicating excitation by prompt capture of electrons at the activator site Followed by the known slower migration and capture of holes (V-k centers). Measurements of core-valence luminescence from BaF2 and intraband luminescence from CsI are also reported. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Weber, MJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS 55-121,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 7 TC 32 Z9 34 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 J9 J LUMIN JI J. Lumines. PD MAY PY 2000 VL 87-9 BP 830 EP 832 DI 10.1016/S0022-2313(99)00430-5 PG 3 WC Optics SC Optics GA 310GK UT WOS:000086818000247 ER PT J AU Bowman, MK Tyryshkin, AM AF Bowman, MK Tyryshkin, AM TI Electron nuclear quadruple resonance for assignment of overlapping spectra SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE ENDOR; electron nuclear multiple resonance; pulsed EPR ID 2-DIMENSIONAL ESEEM; PULSED ENDOR; SPIN; SPECTROSCOPY; FREQUENCIES; ENVELOPE; LIGAND; TOOL AB Multiple resonance methods are important tools in EPR for revealing the network of hyperfine levels of free radicals and paramagnetic centers. The variations of electron nuclear double resonance (ENDOR) or electron spin-echo envelope modulation (ESEEM) techniques help to correlate nuclear frequencies with each other, These methods have limited utility when there is extensive overlap or suspected overlap in the EPR spectrum between different species or different orientations. In the ENDOR spectrum, overlap and second-order shifts of lines also leads to ambiguity in assignment and interpretation. A new electron nuclear multiple resonance method is presented here that is based on population transfer ENDOR. It is a quadruple resonance method that correlates ENDOR lines and reveals the network of hyperfine levels in samples with unoriented paramagnetic species and in samples with overlapping EPR or ENDOR lines. (C) 2000 Academic Press. C1 Pacific Nw Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Russian Acad Sci, Inst Chem Kinet & Combust, Novosibirsk 630090, Russia. RP Bowman, MK (reprint author), Pacific Nw Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RI Tyryshkin, Alexei/A-5219-2008; Bowman, Michael/F-4265-2011 OI Bowman, Michael/0000-0003-3464-9409 NR 24 TC 3 Z9 3 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD MAY PY 2000 VL 144 IS 1 BP 74 EP 84 DI 10.1006/jmre.2000.2043 PG 11 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 313NC UT WOS:000087004900009 PM 10783275 ER PT J AU Parker, GJ Cerjan, C Hewett, DW AF Parker, GJ Cerjan, C Hewett, DW TI Embedded curve boundary method for micromagnetic simulations SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE micromagnetic simulation; finite difference; Co dots; magnetic reversal; magnetic vortex ID STANDARD PROBLEM; SQUARE GRIDS AB The physical and numerical difficulties associated with inadequate boundary resolution in finite differencing applications is alleviated by the embedded curve boundary (ECB) method. The use of this technique in three-dimensional micromagnetic simulations shows more realistic boundary effects on smooth non-rectangular objects without increasing mesh resolution or computational requirements. Results of the new algorithm are presented that show the effect of smooth boundaries on magnetization field determination. A comparison of converged results with other published micromagnetic algorithms are shown for a model reference problem. Additionally, the hysteretic response of submicron-scale cobalt structures is compared with experimental measurements demonstrating the utility of the approach. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Parker, GJ (reprint author), Seagate Res, 2403 Sidney St, Pittsburgh, PA 15203 USA. NR 12 TC 5 Z9 5 U1 0 U2 1 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 MAY PY 2000 VL 214 IS 1-2 BP 130 EP 138 DI 10.1016/S0304-8853(00)00043-3 PG 9 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 313LU UT WOS:000087001800018 ER PT J AU Lee, SJ Kim, KJ Canfield, PC Lynch, DW AF Lee, SJ Kim, KJ Canfield, PC Lynch, DW TI Investigation of optical and magneto-optical constants and their surface-oxide-layer effects of single-crystalline GdCo2 SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE magneto-optics; spectroscopic ellipsometry; three-phase model; optical conductivity ID SPECTROSCOPIC ELLIPSOMETRY; THIN-FILMS; GD AB We investigated the optical. and magneto-optical properties of single-crystalline GdCo2 by spectroscopic ellipsometry (SE) and magneto-optical Kerr spectrometry (MOKS). The diagonal component of the optical conductivity tensor of the compound was obtained by SE in the 1.5-5.5 eV region and the off-diagonal component by using the measured magneto-optical parameters (Kerr rotation and ellipticity) by MOKS and the SE data. The measured spectra were corrected for the surface oxide layer by employing a three-phase model treating the oxide layer as nonmagnetic with constant refractive index. The magnitude of the diagonal component becomes enhanced and the optical transition structures of the off-diagonal component become more pronounced by the oxide correction. The overall optical and magneto-optical data are discussed in terms of the calculated spin-polarized band structure and optical absorption of the compound and the effect of the surface oxide layer. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Konkuk Univ, Dept Phys, Seoul 143701, South Korea. RP Lee, SJ (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Canfield, Paul/H-2698-2014 NR 26 TC 5 Z9 5 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD MAY PY 2000 VL 213 IS 3 BP 312 EP 320 DI 10.1016/S0304-8853(00)00010-X PG 9 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 310JY UT WOS:000086823800010 ER PT J AU Holesinger, TG Foltyn, SR Arendt, PN Kung, H Jia, QX Dickerson, RM Dowden, PC DePaula, RF Groves, JR Coulter, JY AF Holesinger, TG Foltyn, SR Arendt, PN Kung, H Jia, QX Dickerson, RM Dowden, PC DePaula, RF Groves, JR Coulter, JY TI The microstructure of continuously processed YBa2Cu3Oy coated conductors with underlying CeO2 and ion-beam-assisted yttria-stabilized zirconia buffer layers SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID O THIN-FILMS; ORDERED-DEFECT STRUCTURE; PULSED-LASER DEPOSITION; SUPERCONDUCTING FILMS; ORIENTATION; INTERFACES; ALLOYS; TAPES; PHASE; MGO AB The microstructural development of YBa2Cu3Oy (Y-123) coated conductors based on the ion-beam-assisted deposition (IBAD) of yttria-stabilized zirconia (YSZ) to produce a biaxially textured template is presented. The architecture of the conductors was Y-123/CeO2/IBAD YSZ/Inconel 625. A continuous and passivating Cr2O3 layer forms between the YSZ layer and the Inconel substrate. CeO2 and Y-123 are closely lattice-matched. and misfit strain is accommodated at the YSZ/CeO2 interface. Localized reactions between the Y-123 film and the CeO2 buffer layer result in the formation of BaCeO3, YCuO2, and CuO. The positive volume change that occurs from the interfacial reaction may act as a kinetic barrier that limits the extent of the reaction. Excess copper and yttrium generated by the interfacial reaction appear to diffuse along grain boundaries and intercalate into Y-123 grains as single layers of the Y-247, Y-248, or Y-224 phases. The interfacial reactions do not preclude the attainment of high critical currents (I-c) and current densities (J(c)) in these films nor do they affect to any appreciable extent the nucleation and alignment of the Y-123 film. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Holesinger, TG (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Jia, Q. X./C-5194-2008 NR 39 TC 44 Z9 45 U1 1 U2 10 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 2000 VL 15 IS 5 BP 1110 EP 1119 DI 10.1557/JMR.2000.0158 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 311DR UT WOS:000086869900012 ER PT J AU Zhu, S Su, CH Lehoczky, SL George, MA Lowndes, DH AF Zhu, S Su, CH Lehoczky, SL George, MA Lowndes, DH TI Surface texture and structure of ZnO films synthesized by off-axis sputtering deposition SO JOURNAL OF MATERIALS RESEARCH LA English DT Article AB Morphology and structure of ZnO films deposited on (0001) sapphire and glass substrates by off-axis sputtering were investigated at various temperatures and pressures. All films show highly textured structures on glass substrates and epitaxial growth on sapphire substrates. The full width at half-maximum of theta rocking curves for epitaxial films is less than 0.5 degrees. In textured films, it rises to several degrees. The trend of surface textures in films grown at low pressures is similar to those grown at high temperatures. A morphology transition from large well-defined hexagonal grains to flat surface was observed at a pressure of 50 mtorr and temperature of 550 degrees C The experiment results are explained by the transport behavior of depositing species. C1 NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, Huntsville, AL 35812 USA. NASA, George C Marshall Space Flight Ctr, Micrograv Sci & Applicat Dept, Huntsville, AL 35812 USA. Univ Alabama, Dept Chem, Huntsville, AL 35899 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Zhu, S (reprint author), NASA, George C Marshall Space Flight Ctr, Univ Space Res Assoc, Huntsville, AL 35812 USA. NR 3 TC 11 Z9 11 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 2000 VL 15 IS 5 BP 1125 EP 1130 DI 10.1557/JMR.2000.0160 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 311DR UT WOS:000086869900014 ER PT J AU Mang, JT Skidmore, CB Hjelm, RP Howe, PM AF Mang, JT Skidmore, CB Hjelm, RP Howe, PM TI Application of small-angle neutron scattering to the study of porosity in energetic materials SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CARBON-BLACK; MORPHOLOGY; BUBBLES; LAW AB Small-angle neutron scattering (SANS) and the method of contrast variation were used to measure porosity and crystallite surface area in the energetic system octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and to gauge the effects of mechanical deformation on the pore-size distribution and crystallite surface area. The crystallite surface area and the presence of voids (pores) in a high explosive system are known to affect its behavior and overall performance. Measures of these two quantities after an insult, resulting from various process and accident scenarios, can be used to predict the performance of an explosive system after process- and accident-related mechanical deformation. The contrast variation technique allows us to discriminate between internal pores and features that are on or contiguous with the crystallite surface. Measurements were conducted on loose powders of HMX (261 and 10 mu m, volume averaged mean particle diameters) and pellets made by uniaxial consolidation to 7 and 10 vol% porosity, respectively. Analysis of the SANS data indicates significant alteration of the intragranular pore structure and systematic shifts in the surface area that are dependent upon mechanical deformation. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mang, JT (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012 NR 26 TC 17 Z9 17 U1 0 U2 8 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 2000 VL 15 IS 5 BP 1199 EP 1208 DI 10.1557/JMR.2000.0170 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 311DR UT WOS:000086869900024 ER PT J AU Sugama, T Webster, R Reams, W Gawlik, K AF Sugama, T Webster, R Reams, W Gawlik, K TI High-performance polymer coatings for carbon steel heat exchanger tubes in geothermal environments SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID INTERFACES AB The most critical issue in developing thermal conductive coatings for the interior surfaces of heat exchanger tubes made from mild carbon steel (MCS), which are used in geothermal power plants at temperatures ranging from 110 degrees to 89 degrees C, is the deposition of scales. These scales, induced by the brine, chemically adhere to the coating surfaces. One of the major factors governing the formation of a strong interfacial bond at interfaces between the coatings and scales was the brine-promoted hydrothermal oxidation of the coatings. In seeking coating unsusceptible to hydrothermal oxidation, two semi-crystalline thermoplastic polymers, polyphenylenesulfide (PPS) and polytetrafluoroethylene (PTFE)-blended PPS, were applied as interior surface coatings to the zinc phosphated MCS tubes. The PPS coating surfaces suffered some oxidation caused by their chemical affinity for FeCl2 in geothermal brine. FeCl2-promoted oxidation of PPS surfaces not only incorporated more oxygen into them, generating a sulfide --> sulfone --> sulfonic acid conformational transformation within the PPS, but also caused the disintegration of PPS, yielding fragmental polychloroaryl compound and ferrous sulfate (FeSO4) derivatives. The FeSO4 reaction product formed at the interfaces between the scale and PPS coating was soluble in water, so that the coatings could be easily removed by highly pressurized water. The oxidation of PPS was considerably inhibited by blending PTFE into it, forming coating surface unsusceptible to hydrothermal oxidation reactions with hot brine. The major reason for such inhibition of oxidation was the formation of a chemically inert PTFE layer segregated from the PPS layer at the outermost surface site of the coating. Hence, the scale easily flaked off from the PTFE-blended PPS coating surfaces. This characteristic of surface was similar to that of the stainless steel surfaces. Nevertheless, both PPS and PTFE-blended PPS coatings can be classified as scale-free coatings. (C) 2000 Kluwer Academic Publishers. C1 Brookhaven Natl Lab, Dept Appl Sci, Energy Efficiency & Conservat Div, Upton, NY 11973 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sugama, T (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Energy Efficiency & Conservat Div, Upton, NY 11973 USA. NR 17 TC 10 Z9 12 U1 2 U2 10 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAY PY 2000 VL 35 IS 9 BP 2145 EP 2154 DI 10.1023/A:1004754204893 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 292ZT UT WOS:000085827300006 ER PT J AU Luo, ZP Zhang, SQ AF Luo, ZP Zhang, SQ TI High-resolution electron microscopy on the X-Mg12ZnY phase in a high strength Mg-Zn-Zr-Y magnesium alloy SO JOURNAL OF MATERIALS SCIENCE LETTERS LA English DT Article ID RE ALLOYS C1 Beijing Inst Aeronaut Mat, Beijing 100095, Peoples R China. Chinese Acad Sci, Beijing Lab Electron Microscopy, Beijing 100080, Peoples R China. RP Luo, ZP (reprint author), Argonne Natl Lab, Div Mat Sci, Bldg 223, Argonne, IL 60439 USA. RI Luo, Zhiping/C-4435-2014 OI Luo, Zhiping/0000-0002-8264-6424 NR 10 TC 183 Z9 197 U1 2 U2 19 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0261-8028 J9 J MATER SCI LETT JI J. Mater. Sci. Lett. PD MAY PY 2000 VL 19 IS 9 BP 813 EP 815 DI 10.1023/A:1006793411506 PG 3 WC Materials Science, Multidisciplinary SC Materials Science GA 303JD UT WOS:000086418000026 ER PT J AU Simner, S Hardy, J Stevenson, J Armstrong, T AF Simner, S Hardy, J Stevenson, J Armstrong, T TI Sintering of non-stoichiometric strontium doped lanthanum chromite SO JOURNAL OF MATERIALS SCIENCE LETTERS LA English DT Article C1 Pacific NW Lab, Dept Chem & Mat Sci, Richland, WA 99352 USA. RP Simner, S (reprint author), Pacific NW Lab, Dept Chem & Mat Sci, POB 999, Richland, WA 99352 USA. RI Hardy, John/E-1938-2016 OI Hardy, John/0000-0002-1699-3196 NR 8 TC 13 Z9 15 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0261-8028 J9 J MATER SCI LETT JI J. Mater. Sci. Lett. PD MAY PY 2000 VL 19 IS 10 BP 863 EP 865 DI 10.1023/A:1006733414271 PG 3 WC Materials Science, Multidisciplinary SC Materials Science GA 307WW UT WOS:000086678000012 ER PT J AU Nieto, MM Truax, DR AF Nieto, MM Truax, DR TI Time-dependent Schrodinger equations having isomorphic symmetry algebras. I. Classes of interrelated equations SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Article ID OPERATOR SQUEEZED STATES; HARMONIC-OSCILLATOR; COHERENT STATES; EVOLUTION OPERATOR; SYSTEMS; INVARIANTS; MASS AB In this paper, we focus on a general class of Schrodinger equations that are time dependent and quadratic in X and P. We transform Schrodinger equations in this class, via a class of time-dependent mass equations, to a class of solvable time-dependent oscillator equations. This transformation consists of a unitary transformation and a change in the "time" variable. We derive mathematical constraints for the transformation and introduce two examples. (C) 2000 American Institute of Physics. [S0022-2488(00)03005-X]. C1 Univ Calif Los Alamos Natl Lab, Theoret Div MSB285, Los Alamos, NM 87545 USA. Univ Calgary, Dept Chem, Calgary, AB T2N 1N4, Canada. RP Nieto, MM (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div MSB285, POB 1663, Los Alamos, NM 87545 USA. NR 44 TC 8 Z9 8 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0022-2488 J9 J MATH PHYS JI J. Math. Phys. PD MAY PY 2000 VL 41 IS 5 BP 2741 EP 2752 DI 10.1063/1.533268 PG 12 WC Physics, Mathematical SC Physics GA 305YD UT WOS:000086568600016 ER PT J AU Nieto, MM Truax, DR AF Nieto, MM Truax, DR TI Time-dependent Schrodinger equations having isomorphic symmetry algebras. II. Symmetry algebras, coherent and squeezed states SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Article ID SYSTEMS AB Using the transformations from paper I, we show that the Schrodinger equations for (1) systems described by quadratic Hamiltonians, (2) systems with time-varying mass, and (3) time-dependent oscillators all have isomorphic Lie space-time symmetry algebras. The generators of the symmetry algebras are obtained explicitly for each case and sets of number-operator states are constructed. The algebras and the states are used to compute displacement-operator coherent and squeezed states. Some properties of the coherent and squeezed states are calculated. The classical motion of these states is demonstrated. (C) 2000 American Institute of Physics. [S0022-2488(00)03105-4]. C1 Univ Calif Los Alamos Natl Lab, Theoret Div MSB285, Los Alamos, NM 87545 USA. Univ Calgary, Dept Chem, Calgary, AB T2N 1N4, Canada. RP Nieto, MM (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div MSB285, POB 1663, Los Alamos, NM 87545 USA. NR 20 TC 8 Z9 8 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0022-2488 J9 J MATH PHYS JI J. Math. Phys. PD MAY PY 2000 VL 41 IS 5 BP 2753 EP 2767 DI 10.1063/1.533269 PG 15 WC Physics, Mathematical SC Physics GA 305YD UT WOS:000086568600017 ER PT J AU Tsai, CY Tam, SY Lu, YF Brinker, CJ AF Tsai, CY Tam, SY Lu, YF Brinker, CJ TI Dual-layer asymmetric microporous silica membranes SO JOURNAL OF MEMBRANE SCIENCE LA English DT Article DE gas separations; inorganic membranes; membrane preparation and structure; microporous and porous membranes; CO2 removal ID GAS SEPARATION; FILMS AB We report a novel sol-gel dip-coating process to form dual-layer microporous silica membranes with improved membrane performance and reproducibility. First, we deposit a surfactant-templated silica (STS) intermediate layer on top of a commercial gamma-alumina support both to improve its 'surface finish' and to prevent a subsequently deposited microporous overlayer from penetrating into the support. Second, membranes are processed under clean room conditions to avoid dust contamination, and third, membranes are vacuum-calcined to promote further pore shrinkage and impart surface hydrophobicity. The resulting asymmetric membrane exhibits a gradual change in pore diameter from 50 Angstrom (gamma-alumina support layer) to 10-12 Angstrom (STS intermediate layer), and then to 3-4 Angstrom (30 nm thick, ultramicroporous silica top-layer). Compared to a single-layer process using only the microporous overlayer, the dual-layer process improves both flux and selectivity. For the industrially important problem of natural gas purification, the combined CO2 flux ((3-0.5)x 10(-4) cm(3)(STP)/s/cm(2)/cm Hg) and CO2/CH4 separation factors (200-600) are superior to all previously reported values for the separation of a 50/50 (v/v) CO2/CH4 gas mixture. In addition, the membrane selectively separated hydrogen from a simulated reformate from partial oxidation of methanol as evidenced by a high concentration of hydrogen recovery. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ New Mexico, NSF, Ctr Micro Engn Mat, Albuquerque, NM 87106 USA. Sandia Natl Labs, Adv Mat Lab, Albuquerque, NM 87106 USA. RP Tsai, CY (reprint author), Univ New Mexico, NSF, Ctr Micro Engn Mat, 1001 Univ Blvd SE, Albuquerque, NM 87106 USA. NR 24 TC 164 Z9 172 U1 5 U2 26 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0376-7388 J9 J MEMBRANE SCI JI J. Membr. Sci. PD MAY 1 PY 2000 VL 169 IS 2 BP 255 EP 268 DI 10.1016/S0376-7388(99)00343-9 PG 14 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA 299LC UT WOS:000086199200009 ER PT J AU O'Connell, S Lawson, RD Watwood, ME Lehman, RM AF O'Connell, S Lawson, RD Watwood, ME Lehman, RM TI BASIC program for reduction of data from community-level physiological profiling using Biolog microplates: rationale and critical interpretation of data SO JOURNAL OF MICROBIOLOGICAL METHODS LA English DT Article DE BASIC; Biolog; community-level; data reduction ID SUBSTRATE UTILIZATION PATTERNS; CARBON-SOURCE UTILIZATION; C-SOURCE UTILIZATION; MICROBIAL COMMUNITIES AB A BASIC program is offered that reduces data resulting from mixed-species inoculations into Biolog microplates. The procedures of the program are supported by a critical review of the literature relating to Biolog data reduction. The availability of standardized, accelerated data reduction protocols will facilitate study comparisons and allow efficient evaluation of new data reduction approaches. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Dept Biotechnol, Idaho Falls, ID 83415 USA. Idaho State Univ, Dept Biol Sci, Pocatello, ID 83209 USA. RP Lehman, RM (reprint author), Idaho Natl Engn & Environm Lab, Dept Biotechnol, POB 1625 MS 2203, Idaho Falls, ID 83415 USA. OI Lehman, Michael/0000-0002-3391-3178 NR 14 TC 15 Z9 17 U1 2 U2 8 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 MAY PY 2000 VL 40 IS 3 BP 213 EP 220 DI 10.1016/S0167-7012(00)00128-7 PG 8 WC Biochemical Research Methods; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA 318HZ UT WOS:000087279000003 PM 10802137 ER PT J AU Hansen, MC Palmer, RJ White, DC AF Hansen, MC Palmer, RJ White, DC TI Flowcell culture of Porphyromonas gingivalis biofilms under anaerobic conditions SO JOURNAL OF MICROBIOLOGICAL METHODS LA English DT Article DE biofilm; anaerobic; laser confocal microscopy; Porphyromonas gingivalis; plaque; periodontal disease AB We have developed an anaerobic biofilm culture system. The system is inexpensive, simple to use and, unlike an anaerobic glovebox, requires no dedicated space. As a test of the system, Porphyromonas gingivalis was cultured under low oxygen (1-2 ppm) and under anaerobic conditions (less than or equal to 0.1 ppm O-2). In the presence of small amounts of oxygen, the organism attached and formed an initial biofilm over the course of 4 h, but the biofilm was unable to maintain its growth and had lost biomass after Is h. Also, ambiguous results were obtained when the biofilm was stained with a viability stain. Under anaerobic conditions, the biofilm was able to continue growth - biomass was greater after 18 h than after 4 h, and the anaerobic biofilm had a less ambiguous staining pattern than did the low-O-2-grown biofilm. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. Tech Univ Denmark, Dept Microbiol, DK-2800 Lyngby, Denmark. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN USA. RP Palmer, RJ (reprint author), NIDCR, NIH, Bldg 30,Room 308,30 Convent Dr, Bethesda, MD 20892 USA. NR 13 TC 22 Z9 22 U1 0 U2 7 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 MAY PY 2000 VL 40 IS 3 BP 233 EP 239 DI 10.1016/S0167-7012(00)00126-3 PG 7 WC Biochemical Research Methods; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA 318HZ UT WOS:000087279000006 PM 10802140 ER PT J AU Emmert-Buck, MR Strausberg, RL Krizman, DB Bonaldo, MF Bonner, RF Bostwick, DG Brown, MR Buetow, KH Chuaqui, RF Cole, KA Duray, PH Englert, CR Gillespie, JW Greenhut, S Grouse, L Hillier, LW Katz, KS Klausner, RD Kuznetzov, V Lash, AE Lennon, G Linehan, WM Liotta, LA Marra, MA Munson, PJ Ornstein, DK Prabhu, VV Prange, C Schuler, GD Soares, MB Tolstoshev, CM Vocke, CD Waterston, RH AF Emmert-Buck, MR Strausberg, RL Krizman, DB Bonaldo, MF Bonner, RF Bostwick, DG Brown, MR Buetow, KH Chuaqui, RF Cole, KA Duray, PH Englert, CR Gillespie, JW Greenhut, S Grouse, L Hillier, LW Katz, KS Klausner, RD Kuznetzov, V Lash, AE Lennon, G Linehan, WM Liotta, LA Marra, MA Munson, PJ Ornstein, DK Prabhu, VV Prange, C Schuler, GD Soares, MB Tolstoshev, CM Vocke, CD Waterston, RH TI Molecular profiling of clinical tissue specimens - Feasibility and applications SO JOURNAL OF MOLECULAR DIAGNOSTICS LA English DT Reprint ID LASER CAPTURE MICRODISSECTION; PROSTATIC INTRAEPITHELIAL NEOPLASIA; GENE-EXPRESSION PATTERNS; MEN1 GENE; SUSCEPTIBILITY LOCUS; DNA MICROARRAYS; SEQUENCE TAGS; ALLELIC LOSS; HUMAN BRAIN; CANCER C1 NCI, Pathogenet Unit, Pathol Lab, NIH, Bethesda, MD 20892 USA. NCI, Canc Genome Anat Project, Off Director, Bethesda, MD 20892 USA. Univ Iowa, Dept Pediat, Iowa City, IA 52242 USA. Univ Iowa, Dept Physiol & Biophys, Iowa City, IA 52242 USA. NICHD, Lab Integrat & Med Biophys, Bethesda, MD USA. Bostwick Labs, Richmond, VA USA. NCI, Lab Populat Genet, Bethesda, MD 20892 USA. Washington Univ, Genome Sequencing Ctr, St Louis, MO USA. Natl Lib Med, Natl Ctr Biotechnol Informat, Bethesda, MD 20894 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Integrated Mol Anal Genomes & Their Express Conso, Livermore, CA USA. NCI, Urol Oncol Branch, Bethesda, MD 20892 USA. British Columbia Canc Res Ctr, Genome Sequence Ctr, Vancouver, BC V5Z 1L3, Canada. NIH, Math & Stat Comp Lab, Ctr Informat Technol, Bethesda, MD 20892 USA. RP Emmert-Buck, MR (reprint author), NCI, Pathogenet Unit, Pathol Lab, NIH, Bldg 10,Room 2A33,9000 Rockville Pike, Bethesda, MD 20892 USA. RI Bonner, Robert/C-6783-2015; Marra, Marco/B-5987-2008; Cole, Kristina/M-3922-2015 NR 52 TC 48 Z9 49 U1 0 U2 2 PU AMER SOC INVESTIGATIVE PATHOLOGY, INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3993 USA SN 1525-1578 J9 J MOL DIAGN JI J. Mol. Diagn. PD MAY PY 2000 VL 2 IS 2 BP 60 EP 66 DI 10.1016/S1525-1578(10)60617-4 PG 7 WC Pathology SC Pathology GA 365EH UT WOS:000089935100002 PM 11272889 ER PT J AU Coderre, JA Gavin, PR Capala, J Ma, R Morris, GM Button, TM Aziz, T Peress, NS AF Coderre, JA Gavin, PR Capala, J Ma, R Morris, GM Button, TM Aziz, T Peress, NS TI Tolerance of the normal canine brain to epithermal neutron irradiation in the presence of p-boronophenylalanine SO JOURNAL OF NEURO-ONCOLOGY LA English DT Article DE boron neutron capture therapy; boronophenylalanine; BNCT; brain; epithermal neutrons; irradiation; normal tissue tolerance ID RELATIVE BIOLOGICAL EFFECTIVENESS; CENTRAL-NERVOUS-SYSTEM; CAPTURE THERAPY; GLIOBLASTOMA-MULTIFORME; B-10(N,ALPHA)LI-7 REACTION; NORMAL TISSUE; BORON; BIODISTRIBUTION; COMPLEX; TUMORS AB Twelve normal dogs underwent brain irradiation in a mixed-radiation, mainly epithermal neutron field at the Brookhaven Medical Research Reactor following intravenous infusion of 950 mg of (10)B-enriched BPA/kg as its fructose complex. The 5 x 10 cm irradiation aperture was centered over the left hemisphere. For a subgroup of dogs reported previously, we now present more detailed analyses including dose-volume relationships, longer follow-ups, MRIs, and histopathological observations. Peak doses (delivered to 1 cm(3) of brain at the depth of maximum thermal neutron flux) ranged from 7.6 Gy (photon-equivalent dose: 11.8 Gy-Eq) to 11.6 Gy (17.5 Gy-Eq). The average dose to the brain ranged from 3.0 Gy (4.5 Gy-Eq) to 8.1 Gy (11.9 Gy-Eq) and to the left hemisphere, 6.6 Gy (10.1 Gy-Eq) to 10.0 Gy (15.0 Gy-Eq). Maximum tolerated 'threshold' doses were 6.7 Gy (9.8 Gy-Eq) to the whole brain and 8.2 Gy (12.3 Gy-Eq) to one hemisphere. The threshold peak brain dose was 9.5 Gy (14.3 Gy-Eq). At doses below threshold, some dogs developed subclinical MRI changes. Above threshold, all dogs developed dose-dependent MRI changes, neurological deficits, and focal brain necrosis. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Washington State Univ, Pullman, WA 99164 USA. Univ Oxford, Churchill Hosp, Res Inst, Oxford, England. SUNY Stony Brook, Sch Med, Dept Pathol, Div Neuropathol, Stony Brook, NY 11794 USA. RP Coderre, JA (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. EM coderre@bnl.gov NR 44 TC 8 Z9 9 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0167-594X J9 J NEURO-ONCOL JI J. Neuro-Oncol. PD MAY PY 2000 VL 48 IS 1 BP 27 EP 40 DI 10.1023/A:1006419210584 PG 14 WC Oncology; Clinical Neurology SC Oncology; Neurosciences & Neurology GA 351CA UT WOS:000089137400004 PM 11026694 ER PT J AU Hair, LM Coronado, PR Reynolds, JG AF Hair, LM Coronado, PR Reynolds, JG TI Mixed-metal oxide aerogels for oxidation of volatile organic compounds SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID METHANOL OXIDATION; CATALYTIC PROPERTIES; SILICA AEROGELS; SPECTROSCOPY AB Aerogels of 100% silica, 8 wt% Zr in silica, 5 wt% V in silica and 100% zirconia were synthesized and tested as oxidation catalysts in the temperature range of 300-700 degrees C for destruction of volatile organic compounds. The silica-based aerogels were all amorphous and had surface areas above 600 m(2)/g after oxidation. The zirconia aerogel was crystalline with a relatively low surface area of 250 m(2)/g. As catalysts for oxidation (using O-2 in He) of CH3OH to CO2, the zirconia aerogel exhibited the highest activity and best selectivity while the silica aerogel exhibited the poorest. Inclusion of Zr at levels as low as 8 wt% into the silica aerogel framework produced activities and selectivities which were very much like the zirconia aerogel. These properties have the impact of producing a Zr based catalyst with high activity, but with thermal stability afforded by Zr-silica mixtures. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Reynolds, JG (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-369, Livermore, CA 94551 USA. NR 46 TC 11 Z9 11 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 270 IS 1-3 BP 115 EP 122 DI 10.1016/S0022-3093(00)00077-6 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 317UA UT WOS:000087244300013 ER PT J AU Cho, JP Martin, SW Meyer, B Kim, KH Torgeson, DR AF Cho, JP Martin, SW Meyer, B Kim, KH Torgeson, DR TI Static B-11 NMR studies of the short range order in alkali metal modified B2S3 glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID DENSITY-MEASUREMENTS; 0-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-0.75 GLASSES; XNA2S+(1-X)B2S3 GLASSES; INFRARED-SPECTROSCOPY; BORATE GLASSES; POLYCRYSTALS; XK(2)S+(1-X)B2S3; SYSTEM AB The B-11 NMR spectra of xRb(2)S + (1 - x)B2S3 glasses in the range 0 less than or equal to x less than or equal to 0.75 and of xCs(2)S + (1 - x)B2S3 glasses in the range 0 less than or equal to x less than or equal to 0.60 are reported. The addition of Rb2S to B2S3 creates on average approximately two and one-half tetrahedral borons for each added sulfur ion, whereas It is found that the addition of Cs2S creates approximately 2 tetrahedral borons for each added sulfur ion. This behavior while more similar to that seen in the alkali borate glasses, contrasts that seen in the Na and K thioborate glasses, where six to eight and three, respectively, tetrahedral borons are formed for every sulfide anion added to the glass. These findings are supported by the IR and B-11 NMR spectra of the di-thioborate polycrystals (c-Rb2S:2B(2)S(3) and c-Cs2S:2B(2)S(3)) whose structures appear to be comprised of two BS4 tetrahedrals and two BS3 trigonals (N-4 similar to 0.5) like that in the alkali di-borate phases for both Rb and Cs. Unlike the B-11 NMR resonances of the sodium thioborate glasses where a single sharp line is observed for the tetrahedral boron site and a single quadrupolar broadened line is observed for all the trigonal sites, a third resonance line is observed at high alkali fractions for the rubidium and cesium thioborate glasses. This new structural feature may arise from asymmetric MBS2 (meta-thioborate groups) or tetrahedral boron groups possessing a non-bridging sulfur. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Martin, SW (reprint author), Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, 3053 Gilman Hall, Ames, IA 50011 USA. NR 27 TC 8 Z9 8 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 270 IS 1-3 BP 205 EP 214 DI 10.1016/S0022-3093(99)00958-8 PG 10 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 317UA UT WOS:000087244300023 ER PT J AU Treacy, MMJ Voyles, PM Gibson, JM AF Treacy, MMJ Voyles, PM Gibson, JM TI Schlafli cluster topological analysis of medium range order in paracrystalline amorphous semiconductor models SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID TETRAHEDRAL SEMICONDUCTORS; MOLECULAR-DYNAMICS; RANDOM NETWORKS; SILICON AB We show that topologically crystalline regions in computer models of amorphous materials can be identified by examining the Schlafli cluster associated with each atom. The Schlafli cluster contains those atoms that define the Schlafli circuit symbol. Different crystalline topologies that have the same Schlafli circuit symbol may be distinguished by considering the number of atoms in the Schlafli cluster. The diameter of the cubic diamond Schlafli cluster in Ge is similar to 0.9 nm, which is typical of the shorter length scales associated with medium range order in amorphous materials. Regions of connected identical Schlafli clusters can be readily identified in models and their combined size provides an intrinsic length scale for describing the medium range order. (C) 2000 Elsevier Science B.V. All rights reserved. C1 NEC Res Inst Inc, Princeton, NJ 08540 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Voyles, PM (reprint author), NEC Res Inst Inc, 4 Independence Way, Princeton, NJ 08540 USA. RI Gibson, Murray/E-5855-2013; OI Gibson, Murray/0000-0002-0807-6224; Voyles, Paul/0000-0001-9438-4284 NR 14 TC 25 Z9 25 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 150 EP 155 DI 10.1016/S0022-3093(99)00794-2 PN A PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 316VY UT WOS:000087189800027 ER PT J AU Biswas, R Li, YP Pan, BC AF Biswas, R Li, YP Pan, BC TI Isotopic effect between hydrogen and deuterium emission in silicon SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID OXIDE-SEMICONDUCTOR TRANSISTORS; AMORPHOUS-SILICON; MODEL; DEGRADATION; DESORPTION; STABILITY; VIBRATION; SI(111); ALLOY; SI AB We find an isotope effect between the breaking of SiH and SiD bands, using tight-binding molecular dynamics simulations. The vibrationally excited Si-D bending modes decay much more rapidly than Si-H bending modes, due to the coupling of SID modes with the interior silicon-phonon modes. The SiD bond is much more stable than the SiH bond. This stability explains the reduced degradation in deuterated metal-oxide-semiconductor (MOS) devices. For germanium, the GeD and GeH bonds have little difference in their stabilities since their vibrational frequencies are greater than the interior Ge-spectrum, consistent with this vibrational coupling model. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, US DOE, Microelect Res Ctr, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Univ Sci & Technol China, Dept Phys, Hefei 230026, Peoples R China. RP Biswas, R (reprint author), Iowa State Univ, US DOE, Microelect Res Ctr, Dept Phys & Astron, Ames, IA 50011 USA. NR 19 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 176 EP 179 DI 10.1016/S0022-3093(99)00806-6 PN A PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 316VY UT WOS:000087189800032 ER PT J AU Baugh, J Han, DX Kleinhammes, A Liu, CL Wu, Y Wang, Q AF Baugh, J Han, DX Kleinhammes, A Liu, CL Wu, Y Wang, Q TI Microstructure and dynamics of hydrogen in a-Si : H detected by nuclear magnetic resonance SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID AMORPHOUS-SILICON AB A proton nuclear magnetic resonance (NMR) study of a-Si:H was carried out on both hydrogen-diluted and nonhydrogen-diluted device quality glow-discharge (GD) a-Si:H films. The main features of the proton spectrum are the previously reported line with a linewidth of a few kHz and a line with a linewidth > 25 kHz. However, the broader line is a superposition of two peaks, rather than a single peak. Spin-lattice relaxation time (T-1) measurements of the non-H-diluted a-Si:H indicate that the spectral component with the greatest width (approximate to 80 kHz) relaxes about four times faster than the approximate to 35 kHz and the few kHz peaks. T-1 measurements cannot resolve components of the H-diluted a-Si:H spectrum and in that case the deviation from a single Gaussian function fitted to the approximate to 35 kHz line is much less. Above room temperature the intensity of the broadest line decreases whereas the narrow peak and a narrower portion of the broad peak increase in intensity. These spectral changes are reversible at temperatures < 200 degrees C. The temperature dependence of the spectra is larger for the non-H-diluted sample. We speculate that the temperature dependence is related to the intensity of the broadest spectral component and that this component may be associated with isolated trapped molecular hydrogen. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wu, Y (reprint author), Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. RI Baugh, Jonathan/F-3879-2011 NR 17 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 185 EP 189 DI 10.1016/S0022-3093(99)00811-X PN A PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 316VY UT WOS:000087189800034 ER PT J AU Su, TN Taylor, PC Chen, SL Crandall, RS Mahan, AH AF Su, TN Taylor, PC Chen, SL Crandall, RS Mahan, AH TI Molecular hydrogen in amorphous silicon revisited SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID PROTON-MAGNETIC-RESONANCE; SI-H; FILMS AB We measured the concentration of molecular hydrogen (Hz) in hydrogenated amorphous silicon (a-Si:H) by nuclear magnetic resonance (NMR) using a Jeener-Broekaert three-pulse sequence. For samples prepared by both plasma enhanced chemical vapor deposition (PECVD) and hot-wire chemical vapor deposition (HWCVD), the concentrations measured by this method are one order of magnitude larger than that inferred from the spin-lattice relaxation time (T-1) of hydrogen bonded to silicon. For the sample prepared by PECVD, we found two different environments for molecular hydrogen, where the relaxation mechanisms differ. Molecular hydrogen in the samples prepared by HWCVD is motionally narrowed even at 8 K, while in the sample prepared by PECVD the molecular hydrogen is almost completely 'frozen in' at 8 K. This difference is attributed to the effect of the host silicon structure. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Taylor, PC (reprint author), Univ Utah, Dept Phys, 115 S 1400, Salt Lake City, UT 84112 USA. NR 14 TC 17 Z9 17 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 195 EP 200 DI 10.1016/S0022-3093(99)00814-5 PN A PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 316VY UT WOS:000087189800036 ER PT J AU Branz, HM AF Branz, HM TI The hydrogen collision model: theory and experiment SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID A-SI-H; AMORPHOUS-SILICON; METASTABILITY; DIFFUSION; KINETICS AB The H collision model of the Staebler-Wronski effect in hydrogenated amorphous silicon attributes light- and carrier-induced metastability to the association in pairs of mobile H that have diffused long distances after excitation from Si-H bonds. This microscopic model is consistent with the constraints imposed by electron spin resonance and other experiments. Mobile H density is the key variable of the quantitative theory describing metastable dangling-bond creation. As predicted, pulsed illumination experiments show that there is an intermediate precursor between electron-hole recombination and metastable dangling-bond (DB) creation. I suggest this precursor is mobile H: whose density normally requires about a millisecond to respond to changes in illumination. The numerical constants describing H emission and trapping within the H collision model are estimated from recent pulsed-illumination experiments. A representative numerical solution of the model is shown. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Branz, HM (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 33 TC 9 Z9 10 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 391 EP 396 DI 10.1016/S0022-3093(99)00739-5 PN A PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 316VY UT WOS:000087189800074 ER PT J AU Biswas, R Li, YP AF Biswas, R Li, YP TI Metastability in amorphous silicon from hydrogen flips SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID COLLISION MODEL AB A new metastability of hydrogen atoms in a-Si:H was found, from molecular dynamics simulations. In the higher energy configuration H is flipped to the backside of the SiH bond, and is bonded to the same silicon atom since the SiH bond is rotated by nearly 180 degrees. This H-flip defect explains structural changes found from infrared absorption, Volume dilation, and nuclear magnetic reasonance measurements. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, US DOE, Microelect Res Ctr, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Univ Sci & Technol China, Dept Phys, Hefei 230026, Peoples R China. RP Biswas, R (reprint author), Iowa State Univ, US DOE, Microelect Res Ctr, Dept Phys & Astron, Ames, IA 50011 USA. NR 16 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 401 EP 404 DI 10.1016/S0022-3093(99)00758-9 PN A PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 316VY UT WOS:000087189800076 ER PT J AU Crandall, RS AF Crandall, RS TI Charge-trapping metastability in doped hydrogenated amorphous silicon SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID MEYER-NELDEL RULE; MECHANISMS; TRANSPORT; DEFECTS AB Transient capacitance measurements on n- and p-type hydrogenated amorphous silicon (a-Si:H) junction structures show metastable hole and electron trapping above the defect-equilibration temperature. Both electrons and holes can be trapped in the same doped layer. Each charge has its own annealing activation energy, virtually independent of dopant type. In both doping types, the majority carrier has the faster annealing time. These features result from making measurements above the isokinetic temperature. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Crandall, RS (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 10 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 423 EP 427 DI 10.1016/S0022-3093(00)00046-6 PN A PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 316VY UT WOS:000087189800081 ER PT J AU Yelon, A Fritzsche, H Branz, HM AF Yelon, A Fritzsche, H Branz, HM TI Electron beam creation of metastable defects in hydrogenated amorphous silicon: hydrogen collision model SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID A-SI-H; DIFFUSION; IRRADIATION; SEMICONDUCTORS; RECOMBINATION; ENERGY AB Metastable dangling bond (DB) creation during keV electron-beam irradiation of hydrogenated amorphous silicon (a-Si:H) is explained with the H collision model of light-induced metastability and several physically reasonable assumptions. Each incident electron creates an electron-hole pair every nm as it traverses the sample, resulting in a 1-nm-radius 'hot tube' extending from the front to the back surface of a film <40 nm thick. Electron-hole pair recombination within the tube excites mobile II out of Si-H bonds. During the 10 ps before the tube cools, mobile H normally annihilates with a DB left at its site of excitation, but it can diffuse up to 2 nm within the tube. Because mobile H are created so close together, there are occasional H collisions to form a metastable two-H complex. As in light-induced metastability, these collisions leave metastable DBs at the sites of excitation. The model predicts linear creation kinetics followed by saturation of the defect density, as observed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Energy Convers Devices, Troy, MI 48084 USA. RP Yelon, A (reprint author), Ecole Polytech, Dept Genie Phys, Montreal, PQ H3C 3A7, Canada. NR 22 TC 17 Z9 17 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 437 EP 443 DI 10.1016/S0022-3093(99)00772-3 PN A PG 7 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 316VY UT WOS:000087189800084 ER PT J AU Liu, X Spiel, CL Pohl, RO Iwaniczko, E Crandall, RS AF Liu, X Spiel, CL Pohl, RO Iwaniczko, E Crandall, RS TI Low temperature internal friction study of light-induced structural instability in hydrogenated amorphous silicon SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID LOW-ENERGY EXCITATIONS; A-SI; RELAXATION AB Light-induced structural change in some different types of a-Si:H and a-Si:D films has been studied by low temperature internal friction measurements. After extended light-soaking at room temperature, the low-temperature internal friction of a-Si:H prepared by both hot-wire and plasma-enhanced chemical-vapor deposition (PECVD) increase to similar to 6 x 10(-6), although their initial internal friction, the amount and the microstructure of hydrogen in both types of films differ. We attribute this similarity to an increase of structural disorder. However, the effect is considerably smaller in similarly prepared hot-wire a-Si:D. Experiments conducted on a sample prepared by hut-wire chemical-vapor deposition (HWCVD) show that this change anneals out at room temperature in about 70 days. Possible relation of the light-induced structural change to the Staebler-Wronski effect (SWE) is discussed. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 SFA Inc, Largo, MD 20774 USA. Cornell Univ, Dept Phys, Ithaca, NY 14853 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Liu, X (reprint author), SFA Inc, Largo, MD 20774 USA. NR 16 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 501 EP 505 DI 10.1016/S0022-3093(00)00050-8 PN A PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 316VY UT WOS:000087189800096 ER PT J AU Nelson, BP Xu, YQ Webb, JD Mason, A Reedy, RC Gedvilas, LM Lanford, WA AF Nelson, BP Xu, YQ Webb, JD Mason, A Reedy, RC Gedvilas, LM Lanford, WA TI Techniques for measuring the composition of hydrogenated amorphous silicon-germanium alloys SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp AB We grow hydrogenated amorphous silicon-germanium alloys by the hot-wire chemical vapor deposition (HWCVD) technique at deposition rates between 0.5 and 1.4 nm per second. We prepared a set of these alloys to determine the concentrations of the alloying elements as measured by various techniques. This set consists of samples throughout the range of germanium alloying from 0% (a-Si:H) to 100% (a-Ge:H). We find that by making the appropriate calibrations and corrections, our compositional measurements agree between the various techniques. Nuclear reaction analysis (NRA), Fourier transform infrared spectroscopy (FTIR)and secondary ion mass spectrometry (SIMS) all yield similar hydrogen contents, within +/-20% for each sample. Electron probe micro-analysis (EPMA) and SIMS yield silicon and germanium contents within +/-7% of each other with results being confirmed by Rutherford backscattering (RBS). EPMA oxygen measurements are affected by oxidized surface layers, thus these data show larger O concentrations than those measured by SIMS. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. SUNY Albany, Dept Phys, Albany, NY 12222 USA. RP Nelson, BP (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 22 TC 12 Z9 12 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 680 EP 684 DI 10.1016/S0022-3093(99)00848-0 PN B PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 315TW UT WOS:000087129900004 ER PT J AU Haerle, R Baldereschi, A Galli, G AF Haerle, R Baldereschi, A Galli, G TI Structural models of amorphous carbon and its surfaces by tight-binding molecular dynamics SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp ID ATOMIC-FORCE MICROSCOPY; DIAMOND-LIKE CARBON; ELECTRONIC-PROPERTIES; NEUTRON-SCATTERING; SUBPLANTATION AB We use liner-scaling tight-binding molecular dynamics to generate three structural models of amorphous carbon (a-C) with different atomic densities, a-C surfaces are then obtained by imposing tensile strain on these computer generated networks until fracture occurs. Our results show that for a given density, the formation energy of surfaces obtained with different tensile strains differ by only a few 10(-1) eV/atom and their structural properties are qualitatively similar. The presence of sp sites at the surface is observed at all densities, but with different concentrations. The surface thicknesses obtained in our simulations agree with experimental data. Furthermore we find that surface roughness increases with the amount of graphitic component in the bulk sample. The same trends of the macroscopic properties are obtained when using a two-center tight-binding (TC-TB) Hamiltonian, an environmental dependent one, and first principles calculations. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Ecole Polytech Fed Lausanne, Inst Phys Appl, CH-1015 Lausanne, Switzerland. PHB Ecublens, IRRMA, CH-1015 Lausanne, Switzerland. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Haerle, R (reprint author), Ecole Polytech Fed Lausanne, Inst Phys Appl, CH-1015 Lausanne, Switzerland. NR 21 TC 8 Z9 8 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 740 EP 745 DI 10.1016/S0022-3093(99)00793-0 PN B PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 315TW UT WOS:000087129900017 ER PT J AU Gao, W Liu, P Crandall, RS Lee, SH Benson, DK Branz, HM AF Gao, W Liu, P Crandall, RS Lee, SH Benson, DK Branz, HM TI Approaches for large-area a-SiC : H photovoltaic-powered electrochromic window coatings SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UT SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp AB We have fabricated 16 cm(2) monolithic, electrochromic (EC) window-coating devices powered by integral semitransparent amorphous silicon carbide (a-SiC:H) photovoltaics (PV). Self-powered PV-EC windows could modulate solar gain in buildings, thereby reducing both heating and cooling requirements. In preparation for work on large-area PV-EC devices, we examined several important new issues. The first issue is control of pinhole shunt density in the PV portion of the coating, and the second is resistive power loss in the transparent conductor contact layers. Adapting an electrochemical process previously demonstrated in a-Si:H, we have been able to electrically isolate shunts in our a-SiC:H devices. We propose a new design for scribing and bus bar connections that can reduce the resistive losses on large area TCO without greatly affecting window appearance. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Branz, HM (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM hbranz@nrel.gov RI Lee, Sehee/A-5989-2011; Liu, Ping/I-5615-2012 NR 10 TC 13 Z9 13 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 1140 EP 1144 DI 10.1016/S0022-3093(99)00918-7 PN B PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 315TW UT WOS:000087129900096 ER PT J AU Gao, W Lee, SH Benson, DK Branz, HM AF Gao, W Lee, SH Benson, DK Branz, HM TI Novel electrochromic projection and writing device incorporating an amorphous silicon carbide photodiode SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 18th International Conference on Amorphous and Microcrystalline Semiconductors (ICAMS 18) CY AUG 23-27, 1999 CL SNOWBIRD, UTAH SP Energy Convers Devices, Japan Steelworks Ltd, MVSystems Inc, Natl Renewable Energy Lab, Princeton Univ, Sanyo Elect Corp, Sony Corp, Syracuse Univ, United Solar Syst Corp, Univ Utah, Xerox Corp AB We describe an electrochromic (EC) device that can be bleached with a light pen, for use in light-on-dark viewgraph projection, signage, and children's toys. Our prototype monolithic, 16 cm(2), writing device modulates the transmittance by more than 90% over a large portion of the visible spectrum by combining a light-sensitive diode with an EC transmission modulation device. The diode is made of hydrogenated amorphous silicon carbide (a-SiC:H). The EC device consists of WO3, ion-conducting LiAlF4, and a NiW0.33O2 counter-electrode. Working together, WO3 and NiW0.33O2 produces a grayish colored state and a higher coloration efficiency compared with WO3 and a V2O5 counterelectrode. Our prototype device has light yellow writing on a black background. Design issues that control the writing speed and image persistency are discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Branz, HM (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Lee, Sehee/A-5989-2011 NR 9 TC 1 Z9 1 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY PY 2000 VL 266 BP 1233 EP 1237 DI 10.1016/S0022-3093(99)00930-8 PN B PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 315TW UT WOS:000087129900114 ER PT J AU Fink, JK AF Fink, JK TI Thermophysical properties of uranium dioxide SO JOURNAL OF NUCLEAR MATERIALS LA English DT Review ID THERMAL-CONDUCTIVITY; UO2-BASED SIMFUEL; HIGH-TEMPERATURE; HEAT-CAPACITY; UO2 FUEL; EXPANSION; BURNUP; OXIDE; PHASE; THO2 AB Experimental data on thermodynamic and transport properties of solid and liquid UO2 have been reviewed and analyzed to obtain consistent equations for the thermophysical properties. Thermodynamic properties that have been assessed include enthalpy, heat capacity, enthalpy of fusion, thermal expansion, density, surface tension and vapor pressure. Transport properties that have been assessed are thermal diffusivity, thermal conductivity, viscosity, emissivity and optical constants. The assessments include a review of the experiments and data, review of previous recommendations, analysis of data to obtain new recommendations, determination of uncertainties in the recommended values, and comparisons of new recommendations with data and previous recommendations. Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Reactor Engn Div, Argonne, IL 60439 USA. RP Fink, JK (reprint author), Argonne Natl Lab, Reactor Engn Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 99 TC 261 Z9 267 U1 13 U2 126 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 MAY PY 2000 VL 279 IS 1 BP 1 EP 18 DI 10.1016/S0022-3115(99)00273-1 PG 18 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 298DE UT WOS:000086123400001 ER PT J AU Lexa, D Leibowitz, L Kropf, J AF Lexa, D Leibowitz, L Kropf, J TI On the reactive occlusion of the (uranium trichloride plus lithium chloride plus potassium chloride) eutectic salt in zeolite 4A SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID WASTE AB The interaction between the (uranium trichloride + lithium chloride + potassium chloride) eutectic sail: and zeolite 4A has been studied by temperature-resolved synchrotron powder X-ray diffraction, evolved gas analysis and differential scanning calorimetry, between 300 and 900 K. The onset of salt occlusion by the zeolite has been detected at 450 K. Evidence of a reaction between zeolitic water and uranium trichloride, leading to the formation of uranium dioxide, has appeared at 600 K. The uranium dioxide particle size increases from 2 nm at 600 K to 25 nm at 900 K - an indication of their extra-zeolitic location. No appreciable degradation of the zeolite structure has been observed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Lexa, D (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI ID, MRCAT/G-7586-2011; Kropf, Arthur/B-8665-2015 NR 20 TC 19 Z9 19 U1 2 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 MAY PY 2000 VL 279 IS 1 BP 57 EP 64 DI 10.1016/S0022-3115(99)00279-2 PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 298DE UT WOS:000086123400006 ER PT J AU Farrell, K Stoller, RE Jung, P Ullmaier, H AF Farrell, K Stoller, RE Jung, P Ullmaier, H TI Hardening of ferritic alloys at 288 degrees C by electron irradiation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID PRESSURE-VESSEL; MECHANISMS; EMBRITTLEMENT; REACTOR AB Tensile specimens of a commercially pure iron, an iron-copper alloy and two ferritic pressure vessel steels, were irradiated at 288 degrees C with 2.5 MeV electrons to doses of 2.82 x 10(23) and 9.35 x 10(23) e(-)/m(2), corresponding to calculated atomic displacement doses of 9.53 x 10(-4) and 3.16 x 10(-3) dpa, respectively. Tensile tests at room temperature showed dose-dependent increases in yield stress and ultimate tensile stress and reductions in uniform elongation, compatible with literature data for A533B steel neutron-irradiated at 288 degrees C to similar displacement levels. No systematic effect of copper content was discerned in these electron irradiations, contrary to expectations based on neutron irradiations. For the limited dose range over which direct comparison can be made, it is concluded that the hardening efficiency of electron irradiations per unit dpa at 288 degrees C is similar to that for neutron irradiations. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Forschungszentrum Julich, D-52425 Julich, Germany. RP Farrell, K (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Stoller, Roger/H-4454-2011 NR 21 TC 10 Z9 10 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 MAY PY 2000 VL 279 IS 1 BP 77 EP 83 DI 10.1016/S0022-3115(99)00270-6 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 298DE UT WOS:000086123400008 ER PT J AU Klueh, RL Alexander, DJ Sokolov, MA AF Klueh, RL Alexander, DJ Sokolov, MA TI Effect of rhenium and osmium on mechanical properties of a 9Cr-2W-0.25V-0.07Ta-0.1C steel SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID CR-W STEELS; BEHAVIOR AB The nuclear transmutation of tungsten to rhenium and osmium in a tungsten-containing steel irradiated in a fission or fusion reactor will change the chemical composition of the steel. To determine the possible consequences of such compositional changes on the mechanical properties, tensile and Charpy impact properties were measured on five 9Cr-2W-0.25V-0.07Ta-0.1C steels that contained different amounts of rhenium, osmium, and tungsten. The mechanical properties changes caused by these changes in composition were minor. Observations were also made on the effect of carbon concentration. The effect of carbon on tensile behavior was minor, but there was a large effect on Charpy properties. Several of the steels showed little effect of tempering temperature on the Charpy transition temperature, a behavior that was tentatively attributed to the low silicon and/or manganese concentration of the experimental steels. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Klueh, RL (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008,MS 6376, Oak Ridge, TN 37831 USA. NR 13 TC 3 Z9 3 U1 1 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 MAY PY 2000 VL 279 IS 1 BP 91 EP 99 DI 10.1016/S0022-3115(99)00269-X PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 298DE UT WOS:000086123400010 ER PT J AU Xu, HF Wang, XF AF Xu, HF Wang, XF TI Crystallization sequence and microstructure evolution of Synroc samples crystallized from CaZrTi2O7 melts SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID ZIRCONOLITE AB Scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and analytical electron microscopy (AEM) studies have been conducted on samples crystallized from melts with a composition of zirconolite {(Ca0.9Gd0.1)Zr(Ti1.9Al0.1)(2)O-7}. The formation of a whole suite of Synroc phases (zirconia, ZrTiO4, zirconolite. perovskite and rutile) has been observed. In the CaZrTi2O7 system, the formation of these phases follows the crystallization sequence of Ti-bearing zirconia --> ZrTiO4 phase --> Zr-rich zirconolite --> Zr-poor zirconolite --> rutile/ perovskite. This sequence is induced by a fractional crystallization process, in which Zr-rich phases tend to crystallize first, resulting in continuous depletion of Zr in melt. Consistent with this melt compositional evolution, the Zr content in the zirconolite decreases from the area next to the ZrTiO4 phase to areas next to rutile or perovskite. High-resolution TEM images show that there are no glassy phases at the grain boundary between zirconolite and perovskite. The Fractional crystallization-induced textural heterogeneity may have a significant impact on the incorporation of radionuclides into crystalline phases and the resistance of radionuclides to leaching processes. Exsolution lamellae and multiple twinning resulting from the phase transition from tetragonal zirconia to monoclinic zirconia may decrease durability of the Synroc. Fast cooling of the melt may produce more zirconolite phase and relatively uniform texture. In general, however, a Synroc prepared by melting is less uniform in texture than that prepared by a sol-gel method. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ New Mexico, Dept Earth & Planetary Sci, Transmiss Electron Microscopy Lab, Albuquerque, NM 87131 USA. Sandia Natl Labs, Carlsbad, NM 88220 USA. RP Xu, HF (reprint author), Univ New Mexico, Dept Earth & Planetary Sci, Transmiss Electron Microscopy Lab, Albuquerque, NM 87131 USA. NR 22 TC 20 Z9 26 U1 1 U2 4 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 MAY PY 2000 VL 279 IS 1 BP 100 EP 106 DI 10.1016/S0022-3115(99)00272-X PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 298DE UT WOS:000086123400011 ER PT J AU Groch, MW Belzberg, AS DePuey, EG Erwin, WD Marshall, RC Kamran, M Ali, A Nichols, K Hendel, RC Barnett, CA AF Groch, MW Belzberg, AS DePuey, EG Erwin, WD Marshall, RC Kamran, M Ali, A Nichols, K Hendel, RC Barnett, CA TI Evaluation of ventricular performance using gated blood pool SPECT: A multicenter study. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Northwestern Univ, Sch Med, Chicago, IL 60611 USA. St Pauls Hosp, Vancouver, BC V6Z 1Y6, Canada. St Lukes Roosevelt Hosp, New York, NY 10025 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. Rush Univ, Chicago, IL 60612 USA. Columbia Univ, New York, NY USA. VA Med Ctr Martinez, Martinez, CA USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 15 BP 5P EP 5P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400016 ER PT J AU Zamora, PO Kim, HS Ferretti, JA Choi, JS Tio, FO Bhargava, B Osaki, S Som, P Waksman, R Kuan, HM Oster, ZH AF Zamora, PO Kim, HS Ferretti, JA Choi, JS Tio, FO Bhargava, B Osaki, S Som, P Waksman, R Kuan, HM Oster, ZH TI Re-188-stents for preventing restenosis. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Cardiovasc Res Fdn, Washington, DC USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Biomed Res Fdn S Texas, San Antonio, TX USA. InnerDyne Inc, Salt Lake City, UT USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 28 BP 8P EP 8P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400029 ER PT J AU Qi, J Huesman, RH AF Qi, J Huesman, RH TI Lesion detectability of MAP reconstruction using computer observer: A theoretical study. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. RI Qi, Jinyi/A-1768-2010 OI Qi, Jinyi/0000-0002-5428-0322 NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 70 BP 18P EP 19P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400071 ER PT J AU Lee, IJ Vaquero, JJ Barbosa, FJ Seidel, J Green, MV AF Lee, IJ Vaquero, JJ Barbosa, FJ Seidel, J Green, MV TI A high performance phoswich detector module for small animal PET. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 NIH, Ctr Clin, Bethesda, MD 20892 USA. Thomas Jefferson Natl Lab, Newport News, VA USA. RI Vaquero, Juan Jose/D-3033-2009 OI Vaquero, Juan Jose/0000-0001-9200-361X NR 0 TC 1 Z9 1 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 MAY PY 2000 VL 41 IS 5 SU S MA 74 BP 19P EP 20P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400075 ER PT J AU Huesman, RH Klein, GJ Reutter, BW Botvinick, EH Budinger, TF AF Huesman, RH Klein, GJ Reutter, BW Botvinick, EH Budinger, TF TI Evaluation of respiratory compensation efforts in cardiac PET. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. Univ Calif San Francisco, San Francisco, CA 94143 USA. NR 0 TC 1 Z9 1 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 MAY PY 2000 VL 41 IS 5 SU S MA 79 BP 21P EP 21P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400080 ER PT J AU McPherson, DW Knapp, FF AF McPherson, DW Knapp, FF TI Evaluation of M-1 and M-2, mAChR subtypes in aging and Alzheimer's rat models with dual-labeled E/Z-RR-IQNP. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 93 BP 24P EP 24P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400094 ER PT J AU Fowler, JS Logan, J Gimi, R Ding, YS Franceschi, D Wang, GJ Volkow, ND Pappas, N Schlyer, D Atkins, HL AF Fowler, JS Logan, J Gimi, R Ding, YS Franceschi, D Wang, GJ Volkow, ND Pappas, N Schlyer, D Atkins, HL TI Comparative studies of [C-11]clorgyline and deuterium substituted [C-11]clorgyline for measuring monoamine oxidase A (MAO A). SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 98 BP 25P EP 25P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400099 ER PT J AU Volkow, ND Wang, GJ Fowler, JS Franceschi, M Gerasimov, H Franceschi, D Maynard, LS Logan, J Gatley, SJ Ding, YS Wong, CT Pappas, NR AF Volkow, ND Wang, GJ Fowler, JS Franceschi, M Gerasimov, H Franceschi, D Maynard, LS Logan, J Gatley, SJ Ding, YS Wong, CT Pappas, NR TI Effects of Ritalin in brain dopamine concentration. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 1 U2 3 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 MAY PY 2000 VL 41 IS 5 SU S MA 103 BP 27P EP 27P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400104 ER PT J AU Gifford, AN Gatley, SJ Volkow, ND AF Gifford, AN Gatley, SJ Volkow, ND TI In vivo binding of H-[3]N-methylspiperone to 5-HT2 receptors and the effect of the 5-HT releaser, fenfluramine. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 261 BP 66P EP 67P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400262 ER PT J AU Rogoz, R Telang, FW Gifford, AN Gatley, SJ Volkow, ND AF Rogoz, R Telang, FW Gifford, AN Gatley, SJ Volkow, ND TI Towards a quantitative understanding of the effects of dopamine on the in vivo binding of raclopride. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 265 BP 67P EP 68P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400266 ER PT J AU Juweid, M Sparks, R Yeldell, D Stadtmauer, E Goldenberg, DM AF Juweid, M Sparks, R Yeldell, D Stadtmauer, E Goldenberg, DM TI Clinical and dosimetric validation of a safe level of whole-body Y-90 (111 MBQ/M-2) for re-infusion of hematopoietic stem cells (HSC) following high-dose radioimmunotherapy (RAIT) with Y-90-labeled monoclonal antibodies (MABs). SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Hosp Univ Penn, Philadelphia, PA 19104 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Garden State Canc Ctr, Belleville, NJ USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 312 BP 79P EP 79P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400313 ER PT J AU Groch, MW Marshall, RC Erwin, WD Spies, SM Barnett, CA AF Groch, MW Marshall, RC Erwin, WD Spies, SM Barnett, CA TI Left ventricular ejection fraction computed from gated SPECT blood pool imaging correlates with conventional planar imaging. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 VA Med Ctr Martinez, Martinez, CA USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Northwestern Univ, Chicago, IL 60611 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 388 BP 98P EP 98P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400389 ER PT J AU Gatley, SJ Volkow, ND Pyatt, B Gifford, AN AF Gatley, SJ Volkow, ND Pyatt, B Gifford, AN TI Neuroreceptor and motor activity changes after methamphetamine administration. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 412 BP 104P EP 104P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400413 ER PT J AU Gerasimiov, MR Franceschi, M Volkow, ND Pappas, NR Dewey, SL AF Gerasimiov, MR Franceschi, M Volkow, ND Pappas, NR Dewey, SL TI Synergistic elevations in nucleus accumbens (NAC) dopamine (DA) produced by nicotine and methylphenidate (MP). SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 411 BP 104P EP 104P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400412 ER PT J AU Gerasimov, MR Franceschi, M Volkow, ND Dewey, SL AF Gerasimov, MR Franceschi, M Volkow, ND Dewey, SL TI Synergistic accumbens elevations in nucleus accumbens (NACC) dopamine (DA) produced by cocaine and nicotine. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 414 BP 105P EP 105P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400415 ER PT J AU Volkow, ND Wang, GJ Fischman, MW Foltin, R Fowler, JS Franceschi, D Franceschi, M Logan, J Gatley, SJ Ding, YS Wong, CT Hitzemann, R AF Volkow, ND Wang, GJ Fischman, MW Foltin, R Fowler, JS Franceschi, D Franceschi, M Logan, J Gatley, SJ Ding, YS Wong, CT Hitzemann, R TI Effects of route on DA transporter blockade by cocaine. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Columbia Univ, New York, NY USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 416 BP 105P EP 105P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400417 ER PT J AU Volkow, ND Chang, L Wang, GJ Fowler, JS Franceschi, D Hitzemann, R Sedler, M Ding, YS Logan, J Gatley, SJ Wong, CT Pappas, NR AF Volkow, ND Chang, L Wang, GJ Fowler, JS Franceschi, D Hitzemann, R Sedler, M Ding, YS Logan, J Gatley, SJ Wong, CT Pappas, NR TI Brain metabolic changes in methamphetamine abusers. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Los Angeles, Torrance, CA USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 420 BP 106P EP 106P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400421 ER PT J AU Behr, TM Behe, M Angerstein, C Stabin, MG Apostolidis, C Molinet, R Koch, L Roesch, F Becker, W AF Behr, TM Behe, M Angerstein, C Stabin, MG Apostolidis, C Molinet, R Koch, L Roesch, F Becker, W TI Radiopeptide therapy with cholecystokinin-B/gastrin receptor ligands labeled with Auger/conversion electron-versus alpha- or conventional beta-emitters. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Gottingen, D-3400 Gottingen, Germany. ORISE, Oak Ridge, TN USA. Commiss European Communities, Joint Res Ctr, Inst Transuranium Elements, D-7500 Karlsruhe, Germany. Inst Nucl Chem, Mainz, Germany. RI Behe, Martin/E-2941-2013 NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 441 BP 112P EP 112P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400442 ER PT J AU Wang, GJ Volkow, ND Fowler, JS Logan, J Pappas, NR Wong, CT Netusil, N AF Wang, GJ Volkow, ND Fowler, JS Logan, J Pappas, NR Wong, CT Netusil, N TI Evaluation of brain dopamine systems in obese subjects using PET. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 550 BP 139P EP 140P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400551 ER PT J AU Knapp, FF Mirzadeh, S Beets, AL AF Knapp, FF Mirzadeh, S Beets, AL TI Tungsten-188/Re-188 generators using tungsten-188 reactor-produced from irradition of a natural tungsten target. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 1 U2 1 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 MAY PY 2000 VL 41 IS 5 SU S MA 588 BP 149P EP 149P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400589 ER PT J AU Logan, J Fowler, JS Ding, YS Volkow, ND Alexoff, DL AF Logan, J Fowler, JS Ding, YS Volkow, ND Alexoff, DL TI Removing the bias in the graphical analysis method. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 2 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 854 BP 188P EP 189P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400748 ER PT J AU Franceschi, D Volkow, ND Wang, GJ Fowler, JS Franceschi, M Maynard, L Wong, CT Pappas, NR Hitzemann, RJ AF Franceschi, D Volkow, ND Wang, GJ Fowler, JS Franceschi, M Maynard, L Wong, CT Pappas, NR Hitzemann, RJ TI Effect of different doses of ethanol to cerebral glucose metabolism measured with PET. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 SUNY Stony Brook, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 917 BP 203P EP 204P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400811 ER PT J AU Wang, GJ Volkow, ND Fowler, JS Franceschi, D Pappas, NR Wong, CT Felder, C Franceschi, M Maynard, L Hitzemann, RJ AF Wang, GJ Volkow, ND Fowler, JS Franceschi, D Pappas, NR Wong, CT Felder, C Franceschi, M Maynard, L Hitzemann, RJ TI Gender differences in regional brain metabolic responses to alcohol intoxication. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 SUNY Stony Brook, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 916 BP 203P EP 203P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400810 ER PT J AU Fowler, JS Logan, J Franceschi, D Wang, GJ Volkow, ND Ding, YS Liu, N Pappas, N Hitzemann, R AF Fowler, JS Logan, J Franceschi, D Wang, GJ Volkow, ND Ding, YS Liu, N Pappas, N Hitzemann, R TI L-Deprenyl pharmacodynamics PET studies of MAO A and dopamine transporter inhibition in human brain. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 922 BP 205P EP 205P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400816 ER PT J AU Ding, YS Bermel, RA Liu, N Logan, J Garza, V Shea, C MacGregor, R Fowler, JS Volkow, ND AF Ding, YS Bermel, RA Liu, N Logan, J Garza, V Shea, C MacGregor, R Fowler, JS Volkow, ND TI Synthesis and PET studies of [C-11]tamoxifen and (Z) and (E)-4-hydroxytamosifen. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 929 BP 207P EP 207P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400823 ER PT J AU Ding, YS Liu, N Logan, J Garza, V Shea, C MacGregor, R Fowler, JS Volkow, ND AF Ding, YS Liu, N Logan, J Garza, V Shea, C MacGregor, R Fowler, JS Volkow, ND TI Comparative PET studies of nicotinic acetyl-choline receptors using 2-and 6-[F-18]fluoro-3-(2-(S)-azetidinyl- methoxy)pyridine. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 1 Z9 1 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 MAY PY 2000 VL 41 IS 5 SU S MA 949 BP 212P EP 212P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400843 ER PT J AU Srivastava, SC Meinken, GE Freimuth, P AF Srivastava, SC Meinken, GE Freimuth, P TI Biodistribution of In-111 and I-131 labeled adenoviral fiber knob (AdFK) protein in mice. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 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 MAY PY 2000 VL 41 IS 5 SU S MA 1026 BP 231P EP 231P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400920 ER PT J AU Mausner, LF Schnakenberg, H Kolsky, KL Srivastava, SC AF Mausner, LF Schnakenberg, H Kolsky, KL Srivastava, SC TI A new Xe-127 production method at BLIP. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 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 MAY PY 2000 VL 41 IS 5 SU S MA 1091 BP 247P EP 247P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400985 ER PT J AU Glabe, AR Hanrahan, SM Huesman, MK Lohman, J VanBrocklin, HF AF Glabe, AR Hanrahan, SM Huesman, MK Lohman, J VanBrocklin, HF TI Iodophenylpiperazinium quaternary amines: Progress towards I-122 perfusion agents. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 1093 BP 248P EP 248P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892400987 ER PT J AU Srivastava, SC Meinken, GE Atkins, HL Mausner, LF AF Srivastava, SC Meinken, GE Atkins, HL Mausner, LF TI In-vitro and in-vivo stability of tin-117m(4+) chelates. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 1119 BP 254P EP + PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892401013 ER PT J AU Liepe, K Kropp, J Hliscs, R Runge, R Knapp, FF Franke, WG AF Liepe, K Kropp, J Hliscs, R Runge, R Knapp, FF Franke, WG TI Radiation dose of Re-188-HEDP in bone metastases. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Hosp Dresden, Dresden, Germany. NR 0 TC 0 Z9 0 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 MAY PY 2000 VL 41 IS 5 SU S MA 1167 BP 266P EP 266P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892401061 ER PT J AU Blower, PJ Kettle, AG O'Doherty, MJ Coakley, AJ Knapp, FF AF Blower, PJ Kettle, AG O'Doherty, MJ Coakley, AJ Knapp, FF TI Quantitative prediction of Re-188(V)DMSA distribution from Tc-99m(V)DMSA scans for radio-nuclide therapy planning. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. Kent & Canterbury Hosp, Canterbury, Kent, England. NR 0 TC 1 Z9 1 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 MAY PY 2000 VL 41 IS 5 SU S MA 1202 BP 274P EP 274P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 364KW UT WOS:000089892401096 ER PT J AU Beaver, CD AF Beaver, CD TI 5-torsion in the Shafarevich-Tate group of a family of elliptic curves SO JOURNAL OF NUMBER THEORY LA English DT Article ID L-SERIES; POINTS AB We compute the phi-Selmer group for a family of elliptic curves, where phi is an isogeny of degree 5, then find a practical formula for the Cassels-Tate pairing on the phi-Selmer groups and use it to show that a particular Family of elliptic curves have non-trivial 5-torsion in their Shafarevich Tate group. (C) 2000 Academic Press. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Beaver, CD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM cbeaver@sandia.gov NR 23 TC 7 Z9 7 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-314X J9 J NUMBER THEORY JI J. Number Theory PD MAY PY 2000 VL 82 IS 1 BP 25 EP 46 DI 10.1006/jnth.1999.2493 PG 22 WC Mathematics SC Mathematics GA 310FD UT WOS:000086815100003 ER PT J AU Curran, HJ Wu, C Marinov, N Pitz, WJ Westbrook, CK Burcat, A AF Curran, HJ Wu, C Marinov, N Pitz, WJ Westbrook, CK Burcat, A TI The ideal gas thermodynamics of diesel fuel ingredients. I. Naphthalene derivatives and their radicals SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Article DE ab initio calculations; naphthalenic compounds; thermodynamics ID SEMIEMPIRICAL METHODS; ENTHALPIES; MOLECULES; OPTIMIZATION; PARAMETERS AB The molecular fundamentals of 21 naphthalene derivatives were investigated, calculated and evaluated, and their ideal gas thermodynamic properties were calculated, for the sake of simulating the combustion properties of diesel fuel. Ten of these species are stable molecules and 11 are radicals. The molecular fundamentals are calculated using Gaussian 94 ab initio and MOPAC 6 semiempirical programs. The results can be used to estimate the MOPAC performance with polyaromatic species. (C) 2000 American institute of Physics. [S0047-2689(00)00303-2]. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Technion Israel Inst Technol, Fac Aerosp Engn, IL-32000 Haifa, Israel. RP Curran, HJ (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM aer0201@tx.technion.ac.il OI Curran, Henry/0000-0002-5124-8562 NR 50 TC 7 Z9 7 U1 3 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 0047-2689 J9 J PHYS CHEM REF DATA JI J. Phys. Chem. Ref. Data PD MAY-JUN PY 2000 VL 29 IS 3 BP 463 EP 517 DI 10.1063/1.1288947 PG 55 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA 360NZ UT WOS:000089675300004 ER PT J AU Figueroa, E Leman, JT Evans, WJ Ziller, JW Lawrence, JM Thompson, JD AF Figueroa, E Leman, JT Evans, WJ Ziller, JW Lawrence, JM Thompson, JD TI Crystal growth and physical characterization of NaBaVS4 obtained from sodium polysulfide flux SO JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS LA English DT Article DE inorganic compounds; crystal growth; X-ray diffraction; electrical conductivity; magnetic properties ID METAL POLYCHALCOGENIDES; SULFIDES; TRANSITION; BAVS3; PHASE AB Single crystals of NaBaVS4 were grown by precipitation from a sodium polysulfide flux at temperatures below 350 degrees C. The compound crystallizes in the centrosymmetric monoclinic space group P2(1)/n, with four formula units per unit cell. The unit cell dimensions are a = 6.143(12) Angstrom, b = 9.480(2) Angstrom, c = 11.667(2) Angstrom and beta = 102.149(14)degrees. The V5+ cations are surrounded by a tetrahedron of sulfide anions, the Ba2+ cations are coordinated by nine sulfides in a distorted tricapped trigonal prismatic array, and the Na+ cations, which are disordered, are surrounded by seven sulfide ions. Conductivity and magnetic susceptibility studies of a single crystal show that it is a non-magnetic insulator, which suggests that it is a normal valence compound. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lawrence, JM (reprint author), Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. NR 16 TC 1 Z9 1 U1 2 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-3697 J9 J PHYS CHEM SOLIDS JI J. Phys. Chem. Solids PD MAY PY 2000 VL 61 IS 5 BP 773 EP 778 DI 10.1016/S0022-3697(99)00264-4 PG 6 WC Chemistry, Multidisciplinary; Physics, Condensed Matter SC Chemistry; Physics GA 293NL UT WOS:000085859000017 ER PT J AU Yacoby, Y Pindak, R MacHarrie, R Pfeiffer, L Berman, L Clarke, R AF Yacoby, Y Pindak, R MacHarrie, R Pfeiffer, L Berman, L Clarke, R TI Direct structure determination of systems with two-dimensional periodicity SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID X-RAY-DIFFRACTION; PHASE AB We describe a new x-ray method for the direct measurement of structures which have two-dimensional (2D) periodicity, and are positionally correlated with an underlying substrate crystal. Examples include reconstructed crystal structures at interfaces, layered heterostructures, crystalline-amorphous interfaces, and self-assembled structures on crystalline substrates. The structure is obtained by determining the complex scattering factors along the Bragg rods and Fourier back-transforming them into real space. The method for determining the complex scattering factors has two variations. The first is generally applicable. It involves the measurement of the derivative of the diffraction phase along the Bragg rods and the subsequent determination of the diffraction phase using the known structure of the substrate, The second is applicable to 2D systems, with an unknown structure, that are buried within a crystal with a known structure, In this case the diffraction phase is determined without me need to measure its derivative first. We experimentally demonstrate both variations by determining the diffraction phase alone one Bragg rod of a GaAs sample with four buried AlAs monolayers. Using simulated data along the Bragg rods within a volume in reciprocal space, we show that the method yields the three-dimensional structure of 2D systems with atomic resolution. C1 Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. RP Yacoby, Y (reprint author), Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. NR 13 TC 27 Z9 27 U1 2 U2 11 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 MAY 1 PY 2000 VL 12 IS 17 BP 3929 EP 3938 DI 10.1088/0953-8984/12/17/301 PG 10 WC Physics, Condensed Matter SC Physics GA 318MA UT WOS:000087286900001 ER PT J AU Womersley, J AF Womersley, J TI Physics beyond the standard model SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 7th UK Phenomenology Workshop on Collider Physics CY SEP 19-24, 1999 CL UNIV DURHAM, ST JOHNS COLL, DURHAM, ENGLAND SP UK Particle Phys & Astron Res Council HO UNIV DURHAM, ST JOHNS COLL ID SEARCH AB I shall briefly summarize the prospects for extending our understanding of physics beyond the standard model within the next five years. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Womersley, J (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 26 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 MAY PY 2000 VL 26 IS 5 BP 505 EP 511 DI 10.1088/0954-3899/26/5/306 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 321HR UT WOS:000087450500007 ER PT J AU Allanach, BC van der Bij, JJ Dedes, A Djouadi, A Grosse-Knetter, J Hetherington, J Heinemeyer, S Holt, J Hutchcroft, D Kalinowski, J Kane, G Kartvelishvili, V King, SF Lola, S McNulty, R Parker, MA Patel, GD Ross, GG Spira, M Teixeira-Dias, P Weiglein, G Wilson, G Womersley, J Walker, P Webber, BR Wyatt, T AF Allanach, BC van der Bij, JJ Dedes, A Djouadi, A Grosse-Knetter, J Hetherington, J Heinemeyer, S Holt, J Hutchcroft, D Kalinowski, J Kane, G Kartvelishvili, V King, SF Lola, S McNulty, R Parker, MA Patel, GD Ross, GG Spira, M Teixeira-Dias, P Weiglein, G Wilson, G Womersley, J Walker, P Webber, BR Wyatt, T TI Report of the 'Beyond the Standard Model' working group of the 1999 UK Phenomenology Workshop on Collider Physics (Durham) 1. Introduction SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article; Proceedings Paper CT 7th UK Phenomenology Workshop on Collider Physics CY SEP 19-24, 1999 CL UNIV DURHAM, ST JOHNS COLL, DURHAM, ENGLAND SP UK Particle Phys & Astron Res Council HO UNIV DURHAM, ST JOHNS COLL AB The 'Beyond the Standard Model' working group discussed a variety of topics relating to exotic searches at current and future colliders, and the phenomenology of current models beyond the standard model (SM). For example, various supersymmetric (SUSY) and extra dimensions search possibilities and constraints are presented. Fine-tuning implications of SUSY searches are derived. The implications of Higgs (non)discovery are discussed, as well as the program HDECAY. The individual contributions are included separately. Much of the enclosed work is original, although some is reviewed. C1 Univ Cambridge, Dept Appl Math & Theoret Phys, Cambridge CB3 9EW, England. Univ Freiburg, Fak Phys, D-79104 Freiburg, Germany. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Montpellier 2, CNRS, UMR 5825, Lab Phys Math & Theor, F-34095 Montpellier 5, France. Univ Oxford, Nucl Phys Lab, Oxford OX1 3RH, England. Univ Cambridge, Cavendish Lab, Cambridge CB3 OHE, England. DESY, D-22603 Hamburg, Germany. Univ London, Royal Holloway & Bedford New Coll, Dept Phys, Egham TW20 0EX, Surrey, England. Univ Warsaw, Inst Fizyki Teoretycznej, PL-00681 Warsaw, Poland. Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. Univ Manchester, Schuster Lab, Dept Phys & Astron, Manchester M13 9PL, Lancs, England. Univ Southampton, Dept Phys & Astron, Southampton, Hants, England. CERN, Div Theory, CH-1211 Geneva 23, Switzerland. Univ Liverpool, Oliver Lodge Lab, Dept Phys, Liverpool L69 3BX, Merseyside, England. Univ Oxford, Dept Theoret Phys, Oxford OX1 3NP, England. Univ Hamburg, Inst Theoret Phys, D-22761 Hamburg, Germany. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Allanach, BC (reprint author), Univ Cambridge, Dept Appl Math & Theoret Phys, Silver St, Cambridge CB3 9EW, England. RI Hetherington, James/C-7996-2012; Kalinowski, Jan/D-8627-2013; Kartvelishvili, Vakhtang/K-2312-2013; Lola, Smaragda/L-6442-2014 OI Hetherington, James/0000-0001-6993-0319; Lola, Smaragda/0000-0002-1792-1856 NR 0 TC 1 Z9 1 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 MAY PY 2000 VL 26 IS 5 BP 551 EP 552 PG 2 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 321HR UT WOS:000087450500012 ER PT J AU Hassanein, A Konkashbaev, IK AF Hassanein, A Konkashbaev, IK TI Analytical model for collisionless scrape-off-layer plasma during disruptions and enhanced phase of normal operation SO JOURNAL OF PLASMA PHYSICS LA English DT Article ID DIVERTOR AB The structure of a collisionless scrape-off-layer (SOL) plasma in tokamak reactors is studied in order to define the electron distribution function and the corresponding sheath potential between the divertor plate and the edge plasma. The collisionless model is shown to be valid during the thermal phase of plasma disruption, as well as during the newly desired low-recycling normal phase of operation with low-density, high-temperature, edge plasma conditions. An analytical solution is developed by solving the Fokker-Planck equation for electron distribution and balance in the SOL. The solution is in good agreement with numerical studies using Monte Carlo methods. The analytical solutions provide insight into the role of different physical and geometrical processes in a collisionless SOL during disruptions and during the enhanced phase of normal operation over a wide range of parameters. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Troitsk Inst Innovat & Fus Res, Troitsk, Russia. RP Hassanein, A (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0022-3778 J9 J PLASMA PHYS JI J. Plasma Phys. PD MAY PY 2000 VL 63 BP 355 EP 369 DI 10.1017/S0022377800008369 PN 4 PG 15 WC Physics, Fluids & Plasmas SC Physics GA 339PW UT WOS:000088488000005 ER PT J AU Ponomarev, AL Sewell, TD Durning, CJ AF Ponomarev, AL Sewell, TD Durning, CJ TI Surface diffusion and relaxation of partially adsorbed polymers SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE adsorbed polymer; surface diffusion; computer simulation; Rouse model ID BOND-FLUCTUATION MODEL; MONTE-CARLO SIMULATION; DYNAMICS; CHAINS AB We studied by lattice simulation the surface diffusion and relaxation of isolated, self-avoiding polymers partially adsorbed onto a flat surface. The key parameters describing the system are the number of segments in the chain, N, the adsorption energy of a segment, expressed as a dimensionless surface temperature T-s, and the segmental friction factor on the surface relative to that in the hulk, zeta(s)/zeta(b). The simulation data indicate Rouse scaling of the surface diffusion coefficient, D-parallel to, and in-plane relaxation time, tau, versus N for all values of T-B and zeta(s)/zeta(b) studied. A simple application of the Rouse model to a partially adsorbed chain, which ignores fluctuations in adsorbed trains, yields a formula for D-parallel to with the correct N-scaling. It can account for the effects of T-s when zeta(s)/zeta(b) is finite (less than or similar to 10), but it fails when zeta(s)/zeta(b) diverges, predicting no surface diffusion at all, whereas simulations indicate finite surface mobilities facilitated by a caterpillar-like motion. (C) 2000 John Wiley & Sons, Inc. C1 Columbia Univ, Dept Chem Engn & Appl Chem, New York, NY 10027 USA. Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10027 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Durning, CJ (reprint author), Columbia Univ, Dept Chem Engn & Appl Chem, New York, NY 10027 USA. NR 16 TC 8 Z9 8 U1 1 U2 6 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD MAY 1 PY 2000 VL 38 IS 9 BP 1146 EP 1154 DI 10.1002/(SICI)1099-0488(20000501)38:9<1146::AID-POLB6>3.0.CO;2-L PG 9 WC Polymer Science SC Polymer Science GA 301XE UT WOS:000086335200006 ER PT J AU Nelson, RF Sexton, ED Olson, JB Keyser, M Pesaran, A AF Nelson, RF Sexton, ED Olson, JB Keyser, M Pesaran, A TI Search for an optimized cyclic charging algorithm for valve-regulated lead-acid batteries SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 8th Asian Battery Conference CY SEP 08-10, 1999 CL BANGKOK, THAILAND SP Pasminco Metals DE charge/termination algorithms; current-interrupt; cycle-life; oxygen cycle; valve-regulated lead-acid (VRLA) batteries AB Valve-regulated lead-acid (VRLA) batteries are characterized by relatively poor performance in cyclic applications of the order of two hundred to three hundred 100% depth-of-discharge (DoD) cycles. Failure is due to sulfation of the negative plate and softening of the positive active-material. It is felt that this failure mode arises from abnormally high levels of oxygen recombination that arise due to decreases in separator saturation levels as VRLA batteries age. Charging algorithms have been developed to address this changing condition throughout life. The key step is the finish of charge where, traditionally, low currents and low overcharge limits have been employed with poor results. It has been found that using high finishing currents in an alternating charge-rest algorithm results in proper recharge of the negative plate without creating unacceptable temperature increases. This has resulted in deep-discharge lifetimes of 800 to 1000 cycles, particularly when using a charging algorithm employing only partial recharges (97-100% return) interspersed with full conditioning recharges every 10th cycle. With such minimal average overcharge levels, deep-cycle lifetimes approaching 1000 cycles have been achieved without experiencing failure due to massive grid corrosion. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Recombinat Technol, Denver, CO 80204 USA. Optima Batteries, Aurora, CO 80011 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Nelson, RF (reprint author), Recombinat Technol, 909 Santa Fe Dr, Denver, CO 80204 USA. NR 4 TC 27 Z9 31 U1 0 U2 17 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD MAY PY 2000 VL 88 IS 1 BP 44 EP 52 DI 10.1016/S0378-7753(99)00509-1 PG 9 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 317JX UT WOS:000087223200007 ER PT J AU Sindelar, RL Lam, PS Caskey, GR Woo, LY AF Sindelar, RL Lam, PS Caskey, GR Woo, LY TI Flaw stability in mild steel banks in the upper-shelf ductile range - Part I: Mechanical properties SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers (Joint w/ICPVT) CY AUG 01-05, 1999 CL BOSTON, MASSACHUSETTS SP Amer Soc Mech Engineers AB Mechanical properties of 1950's vintage, A285 Grade B carbon steels have been compiled for elastic-plastic fracture mechanics analysis of storage tanks (Lam and Sindelar, 2000). The properties are from standard Charpy V-notch (CVN), 0.4T planform compact tension (C(T)), and tensile (T) specimens machined from archival steel from large water piping. The piping and storage tanks were constructed in the 1950s from semi-killed, hot-rolled carbon steel plate specified as A285 Grade B. Evaluation of potential aging mechanisms at both service conditions shows no loss in fracture resistance of the steel in either case. Site and literature data show that the A285. Grade B steel, at and above approximately 70 degreesF (21 degreesC), is in the upper transition to upper shelf region for absorbed energy and is not subject to cleavage cracking or a brittle fracture mode. Futhermore, the tank sidewalls are 1/2 or 5.8-in. (12.7 or 15.875 mm) thick, and therefore, the J-resistance (J(R)) curve that characterizes material resistance to stable crack extension under elastic-plastic deformation best defines the material fracture toughness. The J(R), curves for several heats of A285, Grade B steel tested at 40 degreesF (4.4 degreesC), a temperature near the average ductile-to-brittle (DBTT) transition temperature (CVN at 15 ft-lb or 20.3 J), are presented. This data is applicable to evaluate flaw stability of the storage tanks that are operated above 70 degreesF (21 degreesC) since, even at 40 degreesF (4.4 degreesC), crack advance is observed to proceed by ductile tearing. [S0094-9930(00)00402-9]. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA. RP Sindelar, RL (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. NR 9 TC 2 Z9 2 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD MAY PY 2000 VL 122 IS 2 BP 162 EP 168 DI 10.1115/1.556173 PG 7 WC Engineering, Mechanical SC Engineering GA 404PW UT WOS:000167110400008 ER PT J AU Lam, PS Sindelar, RL AF Lam, PS Sindelar, RL TI Flaw stability in mild steel tanks in the upper-shelf ductile range - Part II: J-integral-based fracture analysis SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers (Joint w/ICPVT) CY AUG 01-05, 1999 CL BOSTON, MASSACHUSETTS SP Amer Soc Mech Engineers AB The J-integral fracture methodology was applied to evaluate the stability of postulated flaws in mild steel storage tanks. The material properties and the J-resistance (JR) curve were obtained from the archival A285 Grade B carbon steel test data. The J-integral calculation was based on the center-cracked panel (CCP) solution of Shih and Hutchinson (1976, ASME J. Eng. Mater. Technol 98, pp. 289-295). A curvature correction was applied to account for the cylindrical shell configuration. A finite element analysis of an arbitrary flaw in the storage tank demonstrated that the curvature-correct CCP solution is a close approximation. The maximum storage tank fluid level for a postulated flaw size can be established based on the J-integral flaw stability methodology. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Lam, PS (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD MAY PY 2000 VL 122 IS 2 BP 169 EP 173 DI 10.1115/1.556174 PG 5 WC Engineering, Mechanical SC Engineering GA 404PW UT WOS:000167110400009 ER PT J AU DiPrete, DP Peterson, SF Sigg, RA AF DiPrete, DP Peterson, SF Sigg, RA TI Low-flux NAA applications at the Savannah River Site SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 10th International Conference on Modern Trends in Activation Analysis (MTAA-10) CY APR 19-23, 1999 CL NIH, BETHESDA, MARYLAND SP Natl Inst Stand & Technol HO NIH AB Neutron activation analysis using low-flux isotopic neutron sources is put to use in addressing areas of applied interest in managing the Savannah River Site. Some of the applications are unique due the site's operating history and its chemical processing facilities. Because sensitivity needs for many of the applications are not severe, they can be accomplished using a similar to 6 mg Cf-252 neutron activation analysis facility. Overviews of the facility and several example applications are presented. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP DiPrete, DP (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. NR 5 TC 6 Z9 6 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2000 VL 244 IS 2 BP 343 EP 347 DI 10.1023/A:1006775307360 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 338GK UT WOS:000088410600019 ER PT J AU Revay, Z Molnar, GL Belgya, T Kasztovszky, Z Firestone, RB AF Revay, Z Molnar, GL Belgya, T Kasztovszky, Z Firestone, RB TI A new gamma-ray spectrum catalog for PGAA SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 10th International Conference on Modern Trends in Activation Analysis (MTAA-10) CY APR 19-23, 1999 CL NIH, BETHESDA, MARYLAND SP Natl Inst Stand & Technol HO NIH ID ACTIVATION-ANALYSIS AB A major obstacle to the use of the prompt gamma activation analysis (PGAA) method has so far been the lack of a suitable library. Therefore, new measurements have been performed at the PGAA facility at Budapest Research Reactor (BRR) in order to create a prompt gamma-ray catalog for qualitative and quantitative analysis. Prompt gamma-ray energies and associated k(0)-factors have been determined by internal standardization. The resulting catalog contains prompt gamma-ray data from neutron capture and other reactions such as (n,alpha), and decay gamma-ray data from short-lived reaction products. Data have been measured for nearly all stable elements, from hydrogen to uranium. Generally, data for several isotopes are given, to enable isotopic analysis as well. C1 Chem Res Ctr, Inst Isotope & Surface Chem, H-1525 Budapest, Hungary. Lawrence Berkeley Lab, Isotopes Project, Berkeley, CA 94720 USA. RP Revay, Z (reprint author), Chem Res Ctr, Inst Isotope & Surface Chem, H-1525 Budapest, Hungary. OI Firestone, Richard/0000-0003-3833-5546 NR 10 TC 39 Z9 42 U1 0 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 2000 VL 244 IS 2 BP 383 EP 389 DI 10.1023/A:1006795827833 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 338GK UT WOS:000088410600026 ER PT J AU Reinelt, DA Kraynik, AM AF Reinelt, DA Kraynik, AM TI Simple shearing flow of dry soap foams with tetrahedrally close-packed structure SO JOURNAL OF RHEOLOGY LA English DT Article ID HIGHLY CONCENTRATED EMULSIONS; YIELD STRESS; COMPRESSED EMULSIONS; 3-DIMENSIONAL FOAMS; MINIMAL-SURFACES; PLATEAU BORDERS; RHEOLOGY; MODEL; SIMULATION; ELASTICITY AB The microrheology of dry soap foams subjected to quasistatic, simple shearing flow is analyzed. Two different monodisperse foams with tetrahedrally close-packed (TCP) structure are examined: Weaire-Phelan (A15) and Friauf-Laves (C15). The elastic-plastic response is evaluated by using the Surface Evolver to calculate foam structures that minimize total surface area at each value of strain. The foam geometry and macroscopic stress are piecewise continuous functions of strain. The stress scales as T/V-1/3, where T is surface tension and V is cell volume. Each discontinuity corresponds to large changes in foam geometry and topology that restore equilibrium to unstable configurations that violate Plateau's laws. The instabilities occur when the length of an edge on a polyhedral foam cell vanishes. The length can tend to zero smoothly or abruptly with strain. The abrupt case occurs when a small increase in strain changes the energy profile in the neighborhood of a foam structure from a local minimum to a saddle point, which can lead to symmetry-breaking bifurcations. In general, the new structure associated with each stable solution branch results from an avalanche of local topology changes called T1 transitions. Each T1 cascade produces different cell neighbors, reduces surface energy, and provides an irreversible, film-level mechanism for plastic yield behavior. Stress-strain curves and average stresses are evaluated by examining foam orientations that admit strain-periodic behavior. For some orientations, the deformation cycle includes Kelvin cells instead of the original TCP structure; but the foam does not remain perfectly ordered. Bifurcations during subsequent T1 cascades lead to disorder and can even cause strain localization. (C) 2000 The Society of Rheology. [S0148-6055(00)00303-5]. C1 Sandia Natl Labs, Engn Sci Ctr, Albuquerque, NM 87185 USA. So Methodist Univ, Dept Math, Dallas, TX 75275 USA. RP Kraynik, AM (reprint author), Sandia Natl Labs, Engn Sci Ctr, POB 5800, Albuquerque, NM 87185 USA. NR 49 TC 51 Z9 51 U1 1 U2 13 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0148-6055 J9 J RHEOL JI J. Rheol. PD MAY-JUN PY 2000 VL 44 IS 3 BP 453 EP 471 DI 10.1122/1.551096 PG 19 WC Mechanics SC Mechanics GA 312WB UT WOS:000086966000002 ER PT J AU Fouke, BW Farmer, JD Des Marais, DJ Pratt, L Sturchio, NC Burns, PC Discipulo, MK AF Fouke, BW Farmer, JD Des Marais, DJ Pratt, L Sturchio, NC Burns, PC Discipulo, MK TI Depositional facies and aqueous-solid geochemistry of travertine-depositing hot springs (Angel Terrace, Mammoth Hot Springs, Yellowstone National Park, USA) SO JOURNAL OF SEDIMENTARY RESEARCH LA English DT Review ID CARBON-ISOTOPE FRACTIONATION; PYRAMID LAKE SUBBASIN; CALCITE PRECIPITATION; DEVILS-HOLE; NEW-ZEALAND; SEDIMENTARY CARBONATES; BIOLOGICAL CARBONATES; OXYGEN ISOTOPES; URANIUM-SERIES; NORTH-ISLAND AB Petrographic and geochemical analyses of travertine depositing hot springs at Angel Terrace, Mammoth Hot Springs, Yellowstone National Park, have been used to define five depositional facies along the spring drainage system. Spring waters are expelled in the vent facies at 71 to 73 degrees C and precipitate mounded travertine composed of aragonite needle botryoids. The apron and channel facies (43-72 degrees C) is floored by hollow tubes composed of aragonite needle botryoids that encrust sulfide-oxidizing Aquificales bacteria. The travertine of the pond facies (30-62 degrees C) varies in composition from aragonite needle shrubs formed at higher temperatures to ridged networks of calcite and aragonite at lower temperatures. Calcite "ice sheets", calcified bubbles, and aggregates of aragonite needles ("fuzzy dumbbells") precipitate at the air-water interface and settle to pond floors. The proximal-slope facies (28-54 degrees C), which forms. the margins of terracette pools, is composed of arcuate aragonite needle shrubs that create small microterracettes on the steep slope face. Finally, the distal-slope facies (28-30 degrees C) is composed of calcite spherules and calcite "feather" crystals. Despite the presence of abundant microbial mat communities and their observed role in providing substrates for mineralization, the com positions of spring-water and travertine predominantly reflect abiotic physical and chemical processes, Vigorous CO2 degassing causes a +2 unit increase in spring water pH, as well as Rayleigh type covariations between the concentration of dissolved inorganic carbon and corresponding delta(13)C. Travertine delta(13)C and delta(18)O are nearly equivalent to aragonite and calcite equilibrium values calculated from spring water in the higher-temperature (similar to 50-73 degrees C) depositional facies. Conversely, travertine precipitating in the lower-temperature (< similar to 50 degrees C) depositional facies exhibits delta(13)C and delta(18)O values that are as much as 4%0 less than predicted equilibrium values, This isotopic shift may record microbial respiration as well as downstream transport of travertine crystals, Despite the production of H2S anti the abundance of sulfide-oxidizing microbes, preliminary delta(34)S data do not uniquely define the microbial metabolic pathways present in the spring system. This suggests that the high extent of CO2 degassing and large open-system solute reservoir in these thermal systems overwhelm biological controls on travertine crystal chemistry. C1 Univ Illinois, Dept Geol, Urbana, IL 61801 USA. NASA, Ames Res Ctr, Exobiol Branch, Moffett Field, CA 94035 USA. Indiana Univ, Dept Geol Sci, Biogeochem Labs, Bloomington, IN 47405 USA. Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. Univ Notre Dame, Dept Civil Engn & Geol Sci, Notre Dame, IN 46556 USA. RP Fouke, BW (reprint author), Univ Illinois, Dept Geol, 245 Nat Hist Bldg,1301 W Green St, Urbana, IL 61801 USA. RI Burns, Peter/J-3359-2013; OI Burns, Peter/0000-0002-2319-9628 NR 129 TC 150 Z9 152 U1 6 U2 43 PU SEPM-SOC SEDIMENTARY GEOLOGY PI TULSA PA 1731 E 71ST STREET, TULSA, OK 74136-5108 USA SN 1073-130X J9 J SEDIMENT RES JI J. Sediment. Res. PD MAY PY 2000 VL 70 IS 3 BP 565 EP 585 DI 10.1306/2DC40929-0E47-11D7-8643000102C1865D PN A PG 21 WC Geology SC Geology GA 319EQ UT WOS:000087328900015 PM 11543518 ER PT J AU Hendricks, TJ Huang, CD AF Hendricks, TJ Huang, CD TI High-performance radial AMTEC cell design for ultra-high-power solar AMTEC systems SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB Solar thermal Alkali-Metal-Thermal-to-Electric-Conversion (AMTEC) power systems potentially have several important advantages over current solar photovoltaic power systems in ultra-high-power spacecraft applications for medium-earth orbit (MEO) and geosynchronous orbit (GEO) missions. This work presents key aspects of radial AMTEC cell design to achieve high cell performance in solar AMTEC systems delivering larger than 50 kW(e) with AMTEC cell conversion efficiency larger than 22 percent. A new design parameter methodology is demonstrated establishing optimum design parameters in radial cell design to satisfy high-power mission requirements. Specific temperature- and pressure-dependent relationships define critical dependencies between key cell design parameters, particularly the impact of parasitic thermal losses on Beta Alumina Solid Electrolyte (BASE) area requirements, voltage. BASE tube number, and system power production for maximum power-per-BASE-area and optimum efficiency conditions. High-level system tradeoffs are demonstrated using the design parameter methodology to establish high-power radial cell design requirements and determine optimum radial AMTEC designs. [S0199-623(00)00102-7]. C1 Adv Modular Power Syst Inc, Ann Arbor, MI 48108 USA. RP Hendricks, TJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd,M-S 1633, Golden, CO 80401 USA. NR 10 TC 4 Z9 4 U1 2 U2 4 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 MAY PY 2000 VL 122 IS 2 BP 49 EP 55 DI 10.1115/1.1286219 PG 7 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 404NA UT WOS:000167105600001 ER PT J AU Raman, R Mantell, S Davidson, J Wu, CH Jorgensen, G AF Raman, R Mantell, S Davidson, J Wu, CH Jorgensen, G TI A review of polymer materials for solar water heating systems SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB This paper summarizes current research aimed at using polymer materials for glazing and heat exchanger components in solar water healing systems. Functional requirements, relevant polymer properties and an approach for selecting polymers are described for each of these components. Glazing must have high transmittance across the solar spectrum and withstand long term exposure to ultraviolet (UV) light. Candidate glazing materials were tested outdoors for one year in Golden, Phoenix and Miami, as well as exposed for over 300 days in an accelerated testing facility at a concentration ratio of two at the National Renewable Energy Laboratory. Measurements of hemispherical transmittance indicate that a 3.35 mm polycarbonate sheet with a thin film acrylic UV screen provides good transmittance without excessive degradation. The primary challenge to designing a polymer heat exchanger is selecting a polymer that is compatible with potable water and capable of withstanding the high pressure and temperature requirements of domestic hot water systems. Polymers certified for hot water applications by the National Sanitation Foundation or currently used in heat exchangers and exhibit good high temperature characteristics were compared on the basis of a merit value (thermal conductance per unit area per dollar) and manufacturer's recommendations. High temperature nylon (HTN), polypropylene (PP) and cross linked polypropylene (PEX) are recommended for tube components. For structural components (i.e. headers), glass reinforced high temperature nylon (HTN), polyphthalamide (PPA), polyphenylene sulphide (PPS) and polypropylene (PP) are recommended. [S0199-6231(00)00902-3]. C1 Univ Minnesota, Dept Mech Engn, Minneapolis, MN 55455 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Mantell, S (reprint author), Univ Minnesota, Dept Mech Engn, 111 Church St SE, Minneapolis, MN 55455 USA. NR 19 TC 22 Z9 23 U1 0 U2 18 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 MAY PY 2000 VL 122 IS 2 BP 92 EP 100 DI 10.1115/1.1288214 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 404NA UT WOS:000167105600006 ER PT J AU Hodges, JP Short, S Jorgensen, JD Xiong, X Dabrowski, B Mini, SM Kimball, CW AF Hodges, JP Short, S Jorgensen, JD Xiong, X Dabrowski, B Mini, SM Kimball, CW TI Evolution of oxygen-vacancy ordered crystal structures in the perovskite series SrnFenO3n-1 (n=2, 4, 8, and infinity), and the relationship to electronic and magnetic properties SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID MOSSBAUER-SPECTROSCOPY; NEUTRON-DIFFRACTION; HIGH-TEMPERATURE; OXIDES; STATE; SRFEO3-Y; SPIN; BEHAVIOR; SR2FEO4; LATTICE AB Over the oxygen composition range 2.5 less than or equal to x less than or equal to 3.0, the SrFeOx system exists as four distinct compounds with the nominal composition SrnFenO3n-1 (n = 2, 4, 8, and infinity). The end member SrFeO3 (n = infinity) possesses a simple cubic perovskite crystal structure, whereas the oxygen-deficient (n = 2, 4, and 8) members each adopt a different vacancy-ordered perovskite crystal structure. Using time-of-flight neutron powder diffraction, we show that previously proposed structures for the Sr4Fe4O11 (n = 4) and Sr8Fe8O23 (n = 8) compounds are incorrect. We determine the correct crystal structures for Sr4Fe4O11 (orthorhombic, space group Cmmm, a = 10.974(1) Angstrom, b = 7.702(1) Angstrom, and c = 5.473(1) Angstrom) and Sr8Fe8O23 (tetragonal, space group I4/mmm, a = 10.929(1) Angstrom and c = 7.698(1) Angstrom) through comparisons of the goodness of fit for Rietveld refinements of candidate models and bond-length distributions for each model. Using the correct crystal structures, we are able to assign valence states to the Fe crystallographic sites and to achieve consistency with published Mossbauer results for the same compounds. (C) 2000 Academic Press. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. RP Hodges, JP (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Hodges, Jason/K-1421-2013; OI Hodges, Jason/0000-0003-3016-4578 NR 54 TC 240 Z9 244 U1 6 U2 85 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD MAY PY 2000 VL 151 IS 2 BP 190 EP 209 DI 10.1006/jssc.1999.8640 PG 20 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 314KK UT WOS:000087054800005 ER PT J AU Avila-Sakar, AJ Kretsinger, RH Creutz, CE AF Avila-Sakar, AJ Kretsinger, RH Creutz, CE TI Membrane-bound 3D structures reveal the intrinsic flexibility of annexin VI SO JOURNAL OF STRUCTURAL BIOLOGY LA English DT Article DE annexin; annexin VI; 2D crystal; electron crystallography ID 3-DIMENSIONAL STRUCTURE; CRYSTAL-STRUCTURE; CALCIUM; AGGREGATION; RESOLUTION; SYNEXIN; BINDING; FUSION AB Several quasi-ordered arrays and three two-dimensional crystal forms of annexin VT were obtained on artificial lipid monolayers. Three-dimensional reconstructions of the crystal forms exhibit marked differences in the orientations of the two lobes, revealing flexibility of the linker between the two lobes of annexin VI. Evidence is presented that the lobes may bind the monolayer in a parallel orientation, or an antiparallel orientation, in which the second lobe is turned away from the monolayer It is hypothesized that annexin VI may also adopt several conformations in vivo, underlying different functional roles. (C) 2000 Academic Press. C1 Univ Virginia, Dept Pharmacol, Charlottesville, VA 22901 USA. Univ Virginia, Dept Biol, Charlottesville, VA 22901 USA. RP Avila-Sakar, AJ (reprint author), Lawrence Berkeley Natl Lab, 1 Cyclotron Rd,Mail Stop Donner, Berkeley, CA 94720 USA. EM AJAvila-Sakar@lbl.gov FU NCI NIH HHS [CA40042]; NIGMS NIH HHS [GM53266] NR 32 TC 28 Z9 28 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1047-8477 J9 J STRUCT BIOL JI J. Struct. Biol. PD MAY PY 2000 VL 130 IS 1 BP 54 EP 62 DI 10.1006/jsbi.2000.4246 PG 9 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 317HC UT WOS:000087219100006 PM 10806091 ER PT J AU Middleton, P Laulainen, N AF Middleton, P Laulainen, N TI Examining impacts of visibility and PM strategies before implementation SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article; Proceedings Paper CT Air-and-Waste-Management-Association Specialty Conference on Visual Air Quality, Aerosols, and Global Radiation Balance CY SEP 09-12, 1997 CL BARTLETT, NEW HAMPSHIRE SP Air & Waste Management Assoc ID MODEL AB One of the major challenges facing the world today is defining paths to sustainable futures. Part of the challenge is developing a national energy strategy that promotes an adequate energy supply for the United States, while enhancing environmental quality and maintaining U.S. competitiveness in the world economy. To assist in this challenge, we have developed a screening technique to analyze the effectiveness of different proposed emissions reduction strategies. The technique, referred to as the visibility assessment screening technique (VAST), is designed to examine possible impacts on visibility of emission changes of sulfur oxides, nitrogen oxides, volatile organic compounds (i.e., SO2, NOx, and VOC) and fine and coarse particulate matter (PM). The influence of relative humidity, natural aerosols, and the chemical interconnections among sulfur and nitrogen components of aerosols in determining the effectiveness of Clean Air Act Amendment and other projected energy-related emissions changes on eastern and western visibility are explored. The effectiveness of these strategies on particulate matter impacts and potentially on ozone is also noted. C1 RAND Environm Sci & Policy Ctr, Boulder, CO USA. Pacific NW Natl Lab, Richland, WA USA. RP Middleton, P (reprint author), RAND Environm Sci & Policy Ctr, Boulder, CO USA. NR 10 TC 0 Z9 0 U1 0 U2 2 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 MAY PY 2000 VL 50 IS 5 BP 875 EP 880 PG 6 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 313EA UT WOS:000086986300024 PM 10842951 ER PT J AU Tennery, VJ Breder, K Ferber, MK Jenkins, MG AF Tennery, VJ Breder, K Ferber, MK Jenkins, MG TI Flexural fracture strength, fracture locations, and Monte Carlo predictions for a silicon nitride by ten US laboratories SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CERAMICS AB The work reported was conducted to provide a basis for a number of structural ceramic mechanical property standardization activities in the United States, Germany, Japan, and Sweden, A comparison of key property values of a commercial silicon nitride determined in a number of laboratories was a major objective, The work reported was conducted by 10 U.S. laboratories on GN-10 silicon nitride, and represented the U.S. work within an International Energy Agency program including the United States, Germany, Japan, and Sweden, Fracture location analyses showed that fracture location within the inner span often was not a linear function of location within the span. Some of this behavior was explained by random sampling effects based upon simulation predictions, but some was apparently dependent upon friction within the fixtures in spite of efforts to minimize it. Flexural strengths were measured at 25 degrees and 1250 degrees C in air and were analyzed using the two-parameter Weibull model in terms of in and a, using both linear regression (LR) and maximum likelihood (ML) methods. Under the measurement conditions for the 10 room-temperature strength sets, the value of the ML estimator for in varied by as much as 36%, while the value for the sigma(Theta) parameter estimator varied only 3.3%, The LR estimator for tn varied by about 54%. For the high-temperature specimens, the ML estimator for in varied by 48% while the LR estimator varied by 38%, Ranked fracture location analysis showed that the high-temperature fracture locations were more random than those in the room-temperature specimens, and was probably due to friction in the high-temperature fixtures. There was little pin rolling ability in many of the high-temperature fixtures used. Monte Carlo and one-way analysis-of-variance (ANOVA) methods provided insight into the consistency of the strength values. Monte Carlo predictions showed that for room-temperature strength, the maximum likelihood estimator in for all 10 Laboratories fit within the 10% and 90% confidence bounds for 30 specimen sets. The dispersion of the high-temperature data was such that the nl estimator satisfied the model only at the 1% acid 99% confidence levels for the 15 specimen sets. ANOVA results showed that for the room-temperature flexural strength, data from all 10 laboratories were not distinguishable for this evaluator at the 95% confidence level and that scatter within individual data sets was a larger effect than was the variation between the data sets. For the high-temperature data, the results from one laboratory were clearly outside the allowable range at this confidence level. C1 Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. Univ Washington, Dept Mech Engn, Seattle, WA 98195 USA. RP Tennery, VJ (reprint author), Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. NR 20 TC 4 Z9 4 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2000 VL 83 IS 5 BP 1177 EP 1185 PG 9 WC Materials Science, Ceramics SC Materials Science GA 319ER UT WOS:000087329000028 ER PT J AU Tennery, VJ Breder, K Ferber, MK Jenkins, MG AF Tennery, VJ Breder, K Ferber, MK Jenkins, MG TI Tensile fracture behavior of two types of silicon nitride specimen geometries conducted by ten US groups SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CERAMICS AB The work reported was conducted to provide a basis for structural ceramic mechanical property standardization activities under way in the United States, Germany, Japan, and Sweden, All measurements reported here were conducted by 10 US. groups on GN-10 silicon nitride within an International Energy Agency program including the United States, Germany, Japan, and Sweden. This cooperative work included tensile strength studies of two geometries of button-head tensile specimens, The authors conducted some of the measurements and performed data analyses and interpretation. The tensile fracture behavior of GN-10 silicon nitride was studied at room temperature. A total of 150 strain-gaged button-head tensile specimens were measured, One hundred of a straight collet design and 50 of a tapered collet design were fractured. All specimens were highly strain gaged and the outputs for each were: measured during loading to fracture, Bending moments were calculated, Each participating laboratory group fractured 15 tensile specimens, 10 of the straight collet design and 5 of the tapered collet design under rigorously controlled testing conditions. Of 100 straight collet specimens 75 broke,in the gage section. Of 50 tapered collet specimens 34 broke within the gage section. Analysis of the Weibull m and a, estimators at upper and lower confidence bounds of 95% and 5% did not indicate a clear choice between the two designs. For specimens which fractured in the gage section, the unbiased maximum likelihood Weibull estimators for in and a, were 12.5 and 730 and 10.4 and 716, for the straight and tapered collet configurations, respectively. These are not statistically different at the 95% and 5% confidence levels. Strengths were also analyzed in terms of a three-parameter Weibull model. The straight collet specimen data fitted the three parameter model well with a threshold stress estimator gamma of 506 MPa, while the tapered collet specimens provided a poorer fit to the model and had a threshold stress estimator of 432 MPa, a difference of about 15%. Regression analysis indicated that the straight collet grip provided less bias of strength as a function of bending moment. The straight collet specimens showed essentially little dependence of tensile strength upon bending moment in the range of 0% to 6%, while the tapered collet specimens showed a decrease in strength as the bending moment increased from 0% to 4%, However, the regression parameter was low and no significant statistical conclusion could be made regarding the superiority of either of the grip designs. C1 Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. Univ Washington, Dept Mech Engn, Seattle, WA 98195 USA. RP Tennery, VJ (reprint author), Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. NR 14 TC 5 Z9 5 U1 0 U2 4 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2000 VL 83 IS 5 BP 1186 EP 1191 PG 6 WC Materials Science, Ceramics SC Materials Science GA 319ER UT WOS:000087329000029 ER PT J AU McKittrick, J Bacalski, CF Hirata, GA Hubbard, KM Pattillo, SG Salazar, KV Trkula, M AF McKittrick, J Bacalski, CF Hirata, GA Hubbard, KM Pattillo, SG Salazar, KV Trkula, M TI Characterization of photoluminescent (Y1-xEux)(2)O-3 thin films prepared by metallorganic chemical vapor deposition SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID YTTRIUM-OXIDE FILMS; Y2O3; LUMINESCENCE; PHOSPHORS; EU3+Y2O3; EU2O3 AB The purpose of this study was to identify and correlate the microstructural and luminescence properties of europium-doped Y2O3 (Y1-xEux)(2)O-3 thin films deposited by metallorganic chemical vapor deposition (MOCVD), as a function of deposition time and temperature. The influence of deposition parameters on the crystallite size and microstructural morphology were examined, as well as the influence of these parameters on the photoluminescence emission spectra. (Y1-xEux)(2)O-3 thin films were deposited onto (111) silicon and (001) sapphire substrates by MOCVD. The films were grown by reacting yttrium and europium tris(2,2,6,6-tetramethyl-3,5-heptanedionate) precursors with an oxygen atmosphere at low pressures (5 torr (1.7 x 10(3) Pa)) and low substrate temperatures (500 degrees-700 degrees C). The films deposited at 500 degrees C were smooth and composed of nanocrystalline regions of cubic Y2O3, grown in a textured [100] or [110] orientation to the substrate surface. Films deposited at 600 degrees C developed, with increasing deposition time, from a flat, nanocrystalline morphology into a platelike growth morphology with [111] orientation. Monoclinic (Y1-x Eu-x)(2)O-3 was observed in the photoluminescence emission spectra for all deposition temperatures. The increase in photoluminescence emission intensity with increasing postdeposition annealing temperature was attributed to the surface/grain boundary area-reduction effect. C1 Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. Univ Calif San Diego, Mat Sci Program, La Jolla, CA 92093 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP McKittrick, J (reprint author), Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. RI Hirata, Gustavo/E-2532-2016 NR 28 TC 55 Z9 55 U1 0 U2 4 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2000 VL 83 IS 5 BP 1241 EP 1246 PG 6 WC Materials Science, Ceramics SC Materials Science GA 319ER UT WOS:000087329000038 ER PT J AU Yan, Y Evetts, JE Zhang, JI Stobbs, WM AF Yan, Y Evetts, JE Zhang, JI Stobbs, WM TI Characteristic spherulitic microstructure in partial-melt-processed YBa2Cu3Ox/HfO2 SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID YBA2CU3O7-DELTA; SOLIDIFICATION; SUPERCONDUCTOR AB The microstructure of partial-melt-processed YBa2Cu3Ox/ HfO2 has been studied by transmission electron microscopy. A characteristic spherulitic microstructure is formed in the system. A. model for the growth mechanism has been proposed. The critical heterogeneous nucleation of the YBa2Cu3Ox phase appears to occur from the melt in an epitaxially controlled manner on CuO particles. Subsequent growth of YBa2Cu3Ox platelets from the nucleus region is repeatedly interrupted by the nucleation of hafnium-rich phases in the liquid at the solid/liquid interface in a manner that again appears to be epitaxially controlled and that promotes the splay of the c orientation of the YBaCuO grain. C1 Univ Cambridge, Irc Superconduct, Cambridge CB3 0HE, England. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Cambridge, Dept Mat Sci & Met, Cambridge CB2 3QZ, England. RP Yan, Y (reprint author), Univ Cambridge, Irc Superconduct, Madingley Rd, Cambridge CB3 0HE, England. NR 12 TC 1 Z9 1 U1 1 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2000 VL 83 IS 5 BP 1266 EP 1272 PG 7 WC Materials Science, Ceramics SC Materials Science GA 319ER UT WOS:000087329000042 ER PT J AU Fahrenholtz, WG Ellerby, DT Loehman, RE AF Fahrenholtz, WG Ellerby, DT Loehman, RE TI Al2O3-Ni composites with high strength and fracture toughness SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID MECHANICAL-PROPERTIES; SOL-GEL; ALUMINA AB Al2O3-Ni composites were prepared by the reactive hot pressing of Al and NiO. The composites had a two-phase, interpenetrating microstructure and contained similar to 35 vol% Ni. They exhibited an impressively high combination of strength and toughness at room temperature; the four-point bending strength was in excess of 600 MPa with a fracture toughness of more than 12 MPa.m(1/2). Examination of fracture surfaces showed that Ni ligaments underwent ductile deformation during fracture. SEM analysis revealed knife-edged Ni ligaments with a limited amount of debonding around their periphery (i.e., at the Ni-Al2O3 interface), indicating a strong Ni-Al2O3 bond. C1 Univ Missouri, Dept Ceram Engn, Rolla, MO 65409 USA. Sandia Natl Labs, Albuquerque, NM 87106 USA. Adv Mat Lab, Albuquerque, NM 87106 USA. RP Fahrenholtz, WG (reprint author), Univ Missouri, Dept Ceram Engn, Rolla, MO 65409 USA. OI Fahrenholtz, William/0000-0002-8497-0092 NR 15 TC 55 Z9 58 U1 1 U2 10 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2000 VL 83 IS 5 BP 1279 EP 1280 PG 2 WC Materials Science, Ceramics SC Materials Science GA 319ER UT WOS:000087329000045 ER PT J AU Fahrenholtz, WG Ellerby, DT Ewsuk, KG Loehman, RE AF Fahrenholtz, WG Ellerby, DT Ewsuk, KG Loehman, RE TI Forming Al2O3-Al composites with controlled compositions by reactive metal penetration of dense aluminosilicate preforms SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article AB Alumina-Al composites with controlled compositions containing 17 to 31 vol% Al were formed by reactive metal penetration (RMP) of molten Al into dense aluminosilicate preforms. A reaction model has been developed to accurately predict composite Al content from the SiO2:Al2O3 ratio of the preform. The model was tested and validated by comparing predicted composite compositions to those measured for RMP composites made from preforms of known compositions. Aluminosilicate preforms containing 28.1, 39.0, and 54.1 wt% SiO2 were reacted with Al to produce composites with 17, 25, and 31 vol% Al, respectively. These values compare favorably to Al contents of 17.7, 22.7, and 28.6 vol% Al predicted using the reaction model. The differences between predicted and measured values are attributed to the presence of porosity and Si in the composites, as well as impurities in the SiO2 glass phase and porosity in the preforms, none of which is specifically accounted for in the reaction model. C1 Univ New Mexico, Adv Mat Lab, Albuquerque, NM 87106 USA. Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87106 USA. Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Fahrenholtz, WG (reprint author), Univ Missouri, Dept Ceram Engn, Rolla, MO 65401 USA. OI Fahrenholtz, William/0000-0002-8497-0092 NR 11 TC 11 Z9 13 U1 1 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 2000 VL 83 IS 5 BP 1293 EP 1295 PG 3 WC Materials Science, Ceramics SC Materials Science GA 319ER UT WOS:000087329000050 ER PT J AU Amad, MH Houk, RS AF Amad, MH Houk, RS TI Mass resolution of 11,000 to 22,000 with a multiple pass quadrupole mass analyzer SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID LINEAR ION-TRAP; STABILITY REGIONS; SPECTROMETER; FILTER; TIME; PLASMA; 2ND AB CO+ and N-2(+) are separated with resolution of 11,000 [full width half maximum (FWHM)] using a conventional quadrupole mass spectrometer by applying square wave voltages to the entrance and exit lenses to trap or reflect the ions for multiple passes. A resolution of 22,000 (FWHM) with 63% of the total signal remaining is attained using multiple passes when ions are stored between injection pulses. Gated ion extraction also reduces the mass shift and number and intensity of artifact peaks and permits better resolution compared to the performance obtained when the ions are injected continuously. (C) 2000 American Society for Mass Spectrometry. C1 Iowa State Univ, US Dept Energy, Ames Lab, Dept Chem, Ames, IA 50011 USA. RP Houk, RS (reprint author), Iowa State Univ, US Dept Energy, Ames Lab, Dept Chem, Ames, IA 50011 USA. NR 35 TC 3 Z9 3 U1 1 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD MAY PY 2000 VL 11 IS 5 BP 407 EP 415 DI 10.1016/S1044-0305(00)00094-5 PG 9 WC Biochemical Research Methods; Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Biochemistry & Molecular Biology; Chemistry; Spectroscopy GA 306PC UT WOS:000086604200005 ER PT J AU Bruce, JE Anderson, GA Brands, MD Pasa-Tolic, L Smith, RD AF Bruce, JE Anderson, GA Brands, MD Pasa-Tolic, L Smith, RD TI Obtaining more accurate Fourier transform ion cyclotron resonance mass measurements without internal standards using multiply charged ions SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID SPECTROMETRY; IDENTIFICATION; PROTEINS; PROTEOME; NOISE AB Space-charge effects produce frequency shifts in Fourier transform ion cyclotron resonance (FTICR) mass spectrometry and correction for these shifts is necessary for obtaining accurate mass measurements. We report a novel method for obtaining accurate mass calibration to correct for space-charge induced mass shifts without the requirement for internal calibrants. The new approach is particularly well suited for electrospray ionization-FTICR mass spectra that contain multiple charge states of the same molecular species This method, deconvolution of Coulombic affected linearity (DeCAL), is described and presented with several examples demonstrating the increased mass measurement accuracy obtained. DeCAL provides the basis for more routinely obtaining higher mass accuracy measurements in conjunction with chromatographic separations for complex mixture analysis, and obviates the need for internal calibration in many applications. (C) 2000 American Society for Mass Spectrometry. C1 Pacific NW Natl Lab, Environm & Mol Sci Lab, Richland, WA USA. RP Brands, MD (reprint author), POB 999 MSIN,K8-98, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 FU NCI NIH HHS [CA81654] NR 29 TC 55 Z9 57 U1 0 U2 6 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD MAY PY 2000 VL 11 IS 5 BP 416 EP 421 DI 10.1016/S1044-0305(00)00096-9 PG 6 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 306PC UT WOS:000086604200006 PM 10790845 ER PT J AU Kostecki, R Song, XY Kinoshita, K AF Kostecki, R Song, XY Kinoshita, K TI Influence of geometry on the electrochemical response of carbon interdigitated microelectrodes SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID CAPILLARY-ELECTROPHORESIS; CHARACTERIZATION SYSTEMS; ARRAY MICROELECTRODES; MICRODISK ELECTRODES; BATTERY; FILM AB Microelectrodes were fabricated by carbonizing photoresist (700-1000 degrees C) that was patterned on a Si wafer by use of a mask and UV photolithography. Two geometric designs of interdigitated carbon microelectrodes were produced with dimensions of about 500 mu m length and 50 mu m width. The carbon structures were characterized by Raman spectroscopy, atomic force microscopy, and optical microscopy. The electrochemical response of the microelectrodes was investigated by cyclic voltammetry using the I-3(-)/I- redox couple. The collection efficiencies of carbon interdigitated array electrodes (IDAEs) varied from 59 to 90% depending on the cell size, geometry, and generator-collector arrangement. These collection efficiencies are comparable to those reported with multiband (n > 25 bands) IDAEs. (C) 2000 The Electrochemical Society. S0013-4651(99)11-087-5. All rights reserved. C1 Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Kostecki, R (reprint author), Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 22 TC 24 Z9 24 U1 0 U2 5 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 MAY PY 2000 VL 147 IS 5 BP 1878 EP 1881 DI 10.1149/1.1393451 PG 4 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 314UD UT WOS:000087075200046 ER PT J AU Wang, TH Ciszek, TF AF Wang, TH Ciszek, TF TI Growth of large-grain silicon layers by atmospheric iodine vapor transport SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article AB A novel growth method for high speed deposition of large-grain polycrystalline silicon layers on foreign substrates is described. The deposited silicon layers with a thickness of 10-40 mu m on high temperature glass substrate exhibit good uniformity and large grain sizes up to 20 mu m. A typical deposition rate is 3 mu m/min for a source/substrate temperature of 1100/950 degrees C. The growth method is based on iodine vapor transport of silicon at atmospheric pressure with a vertical thermal gradient. A gravity trapping effect allows use of an open-tube system without much loss of the volatile gas species or reduced iodine partial pressure, as is the case in a normal open system involving a carrier gas. The material appears to be an excellent candidate for thin-layer crystalline silicon solar cells. (C) 2000 The Electrochemical Society. S0013-4651(99)11-010-3. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wang, TH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 19 TC 13 Z9 13 U1 1 U2 2 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 MAY PY 2000 VL 147 IS 5 BP 1945 EP 1949 DI 10.1149/1.1393463 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 314UD UT WOS:000087075200058 ER PT J AU Ishimaru, M Dickerson, RM Sickafus, KE AF Ishimaru, M Dickerson, RM Sickafus, KE TI Scanning transmission electron microscopy-energy dispersive X-ray/electron energy loss spectroscopy studies on SiC-on-insulator structures SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ION-IMPLANTED SILICON; MICROSTRUCTURAL EVOLUTION; DOSE DEPENDENCE; BURIED OXIDE; CARBIDE; SIMOX AB Elemental distributions and chemical bonding states of oxygen-ion-implanted SiC have been examined using scanning transmission electron microscopy (STEM) equipped with an energy dispersive X-ray spectrometer (EDX) and an electron energy loss spectrometer (EELS). 6H-SiC single crystals with [0001] orientation were implanted with 180 keV oxygen ions at 650 degrees C to fluences of 0.7 x 10(18) and 1.4 x 10(18) cm(2). STEM-EDX/EELS measurements show that the low-dose sample possesses a buried amorphous SiCxOy layer, and oxygen concentration peaks around the center of the buried amorphous layer. On the other hand, a well-defined SiO2 layer including sell-bonded carbon atoms is formed in the high-dose sample, and this amorphous region has a layered structure due to compositional variations of silicon, carbon, and oxygen. A slight chemical disordering induced by implantation is also confirmed to exist in topmost SiC layer. (C) 2000 The Electrochemical Society. S0013-4651(99)10-053-3. All rights reserved. C1 Kyushu Univ, Dept Mat Sci & Engn, Fukuoka 8128581, Japan. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Ishimaru, M (reprint author), Kyushu Univ, Dept Mat Sci & Engn, Fukuoka 8128581, Japan. NR 18 TC 7 Z9 8 U1 4 U2 5 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 MAY PY 2000 VL 147 IS 5 BP 1979 EP 1981 DI 10.1149/1.1393470 PG 3 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 314UD UT WOS:000087075200065 ER PT J AU Endoh, Y Fukuda, T Wakimoto, S Arai, M Yamada, K Bennington, SM AF Endoh, Y Fukuda, T Wakimoto, S Arai, M Yamada, K Bennington, SM TI Dynamical magnetic susceptibility in the optimum doped LSCO with T-c=37 K SO JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN LA English DT Article; Proceedings Paper CT International Workshop on Magnetic Excitations in Strongly Correlated Electrons CY AUG 19-22, 1999 CL HAMAMATSU, JAPAN SP Inoue Fdn Sci, Oxford Instruments Co Ltd DE dynamical magnetic susceptibility; inelastic neutron scattering; optimum doped LSCO; TOF measurement; incommensurate structure ID SPIN CORRELATIONS; NEUTRON-SCATTERING; LA2-XSRXCUO4; LA2CUO4; FLUCTUATIONS; TEMPERATURE AB Inelastic neutron scattering results in the superconducting state at 10 K of LB1.85Sr0.15CuO4 with T-c = 37 K are presented. A large amount of the data taking with the multi angle PSD system of the chopper spectrometer, MARI were analyzed through a complex procedure of the instrumental correction. We could conclude that the incommensurate magnetic scattering centered ( pi,pi +/- delta) and ( pi +/- delta,pi) with delta = 0.12 rlu persists in high energies as much as 50 meV showing energy independent delta. Then, the incommensurate feature becomes umbiguous in higher energies, but the dynamical magnetic susceptibility chi "(q(2D), omega) extends considerably to higher energies, compared with the recent results of the superconducting YBCO. C1 Tohoku Univ, Inst Mat Res, Aoba Ku, Sendai, Miyagi 9808577, Japan. MIT, Dept Phys, Cambridge, MA 02139 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. KEK, Inst Mat Struct Sci, Tsukuba, Ibaraki 3050801, Japan. Inst Chem Res, Uji, Kyoto 6100011, Japan. Rutherford Appleton Lab, ISIS, Didcot OX11 0QX, Oxon, England. RP Endoh, Y (reprint author), Tohoku Univ, Inst Mat Res, Aoba Ku, Sendai, Miyagi 9808577, Japan. RI Yamada, Kazuyoshi/C-2728-2009 NR 21 TC 14 Z9 14 U1 0 U2 2 PU PHYSICAL SOC JAPAN PI TOKYO PA YUSHIMA URBAN BUILDING 5F, 2-31-22 YUSHIMA, BUNKYO-KU, TOKYO, 113-0034, JAPAN SN 0031-9015 J9 J PHYS SOC JPN JI J. Phys. Soc. Jpn. PD MAY PY 2000 VL 69 SU B BP 16 EP 21 PG 6 WC Physics, Multidisciplinary SC Physics GA 352LU UT WOS:000089218700004 ER PT J AU Joh, YG Orbach, R Wood, GG Hammann, J Vincent, E AF Joh, YG Orbach, R Wood, GG Hammann, J Vincent, E TI Finite size effects on spin glass dynamics SO JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN LA English DT Article DE aging; glassy dynamics; disordered systems; out-of-equilibrium phenomena ID THERMOREMANENT MAGNETIZATION; CORRELATION LENGTH; REPLICA SYMMETRY; FIELD; RELAXATION; SUSCEPTIBILITY; BREAKING; STATES AB The recent identification of a time and temperature dependent spin glass correlation length, xi(t(omega),T), has consequences for samples of finite size. Qualitative arguments are given on this basis for departures from t/t(w) scaling for the time decay of the thermoremanent magnetization, M-TRM (t, t(omega), T), where t is the measurement time after a "waiting time" t(omega) and for the imaginary part of the ac susceptibility, chi "(omega, t). Consistency is obtained for a more rapid decay of M-TRM(t, t(omega), T) With increasing t(omega) when plotted as a function of t/t(omega) for the deviation of the characteristic time for M-TRM(t, t(omega), T) from a linear dependence upon H-2 at larger values of H, and for the deviation of the decay of chi "(omega, t) from omega t scaling upon a change in magnetic field at large values of omega t. These departures from scaling can, in principle, be used to extract the particle size distribution for a given spin glass sample. C1 Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. CEA Saclay, Serv Phys Etat Condense, F-91191 Gif Sur Yvette, France. RP Joh, YG (reprint author), Yeungnam Univ, Dept Phys, Taegu, South Korea. NR 38 TC 13 Z9 13 U1 0 U2 0 PU PHYSICAL SOC JAPAN PI TOKYO PA YUSHIMA URBAN BUILDING 5F, 2-31-22 YUSHIMA, BUNKYO-KU, TOKYO, 113-0034, JAPAN SN 0031-9015 J9 J PHYS SOC JPN JI J. Phys. Soc. Jpn. PD MAY PY 2000 VL 69 SU A BP 215 EP 222 PG 8 WC Physics, Multidisciplinary SC Physics GA 351KR UT WOS:000089156800034 ER PT J AU Balakrishnan, J Boyd, ID Braun, DG AF Balakrishnan, J Boyd, ID Braun, DG TI Monte Carlo simulation of vapor transport in physical vapor deposition of titanium SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID VELOCITIES; MODEL AB In this work, the direct simulation Monte Carlo (DSMC) method is used to model the physical vapor deposition of titanium using electron-beam evaporation. Titanium atoms are vaporized from a molten pool at a very high temperature and are accelerated collisionally to the deposition surface. The electronic excitation of the vapor is significant at the temperatures of interest. Energy transfer between the electronic and translational modes of energy affects the flow significantly. The electronic energy is modeled in the DSMC method and comparisons are made between simulations in which electronic energy is excluded from and included among the energy modes of particles. The experimentally measured deposition profile is also compared to the results of the simulations. It is concluded that electronic energy is an important factor to consider in the modeling of flows of this nature. The simulation results show good agreement with experimental data. (C) 2000 American Vacuum Society. [S0734-2101(00)00803-4]. C1 Cornell Univ, Sibley Sch Mech & Aerosp Engn, Ithaca, NY 14853 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Balakrishnan, J (reprint author), Cornell Univ, Sibley Sch Mech & Aerosp Engn, Ithaca, NY 14853 USA. NR 11 TC 20 Z9 21 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 2000 VL 18 IS 3 BP 907 EP 916 DI 10.1116/1.582274 PG 10 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 315MR UT WOS:000087118000018 ER PT J AU Guillorn, MA Carr, DW Tiberio, RC Greenbaum, E Simpson, ML AF Guillorn, MA Carr, DW Tiberio, RC Greenbaum, E Simpson, ML TI Fabrication of dissimilar metal electrodes with nanometer interelectrode distance for molecular electronic device characterization SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID SINGLE; SPECTROSCOPY AB We report a versatile process for the fabrication of dissimilar metal electrodes with a minimum interelectrode distance of less than 6 nm using electron beam lithography and liftoff pattern transfer. This technique provides a controllable and reproducible method for creating structures suited for the electrical characterization of asymmetric molecules for molecular electronics applications. Electrode structures employing pairs of Au electrodes and non-Au electrodes were fabricated in three different patterns. Parallel electrode structures 300 mu m long with interelectrode distances as low as 10 nm, 75 nm wide electrode pairs with interelectrode distances less than 6 nm, and a multiterminal electrode structure with reproducible interelectrode distances of 8 nm were realized using this technique. The professing issues associated with the fabrication of these structures are discussed along with the intended application of these devices. (C) 2000 American Vacuum Society. [S0734-211X(00)03903-2]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Elect & Comp Engn, Knoxville, TN 37996 USA. Cornell Univ, Natl Nanofabricat Facil, Ithaca, NY 14853 USA. RP Simpson, ML (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Simpson, Michael/A-8410-2011 OI Simpson, Michael/0000-0002-3933-3457 NR 15 TC 37 Z9 37 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 2000 VL 18 IS 3 BP 1177 EP 1181 DI 10.1116/1.591355 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 325AM UT WOS:000087654200009 ER PT J AU Bernhardt, AF Contolini, RJ Jankowski, AF Liberman, V Morse, JD Musket, RG Barton, R Macaulay, J Spindt, C AF Bernhardt, AF Contolini, RJ Jankowski, AF Liberman, V Morse, JD Musket, RG Barton, R Macaulay, J Spindt, C TI Arrays of field emission cathode structures with sub-300 nm gates SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID TRACKS; CONES; FILM AB A novel field emission cathode process has been developed to produce cathode arrays with individual emitter structures having gates with <300 nm diameters. Ion tracking lithography was utilized to pattern submicron features, which can be controlled over the range 30-300 nm, and to create self-aligned and nanosized, gated emitter structures. Nanocone emitter tips were deposited into the gate structure using a variation of the Spindt process. Field emitter arrays having similar to 300 nm gate diameters and an emitter density of 10(8)/cm(2) exhibited a current density or 4 mA/cm(2) for a 45 V gate bias. This ion tracking lithographic approach is suitable and scalable for large flat panel video displays and appears to be commercially viable. (C) 2000 American Vacuum Society. [S0734-211X(00)12303-0]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Candescent Technol Corp, San Jose, CA 95119 USA. RP Bernhardt, AF (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 10 TC 16 Z9 17 U1 1 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 2000 VL 18 IS 3 BP 1212 EP 1215 DI 10.1116/1.591363 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 325AM UT WOS:000087654200017 ER PT J AU Xiu, K Gibson, JM AF Xiu, K Gibson, JM TI Optimized design for the scattering with angular limitation in projection electron-beam lithography based electron projection system SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID SCALPEL SYSTEM; OPTICAL DESIGN AB We investigate the design for a scattering with angular limitation in projection electron-beam lithography (SCALPEL) based electron projection system with a demagnification of -4. By a "field-flip" process we can construct a doubler in which the magnetic field has a flat feature in most of the optic column but opposite sign at two sides connected by a sharp transition region. Such a theoretical model can give a near zero chromatic aberration of rotation and much smaller field curvature and astigmatism. Compared with the conventional doublet, the total image blur caused by aberrations at 1/root 2 mm off-axis distance and 1.5 mrad semiangle aperture at the mask side is about only 24 nln for a column length of 400 mm. A shorter column, less than the current 400 mm, is also favored for further reducing the total aberration. These guarantee that we can choose a much larger aperture angle (compared with present 0.5 mrad) and beam current density in such a SCALPEL projection system to achieve higher throughput while still maintaining current resolution. A practical issue for possible magnetic lens design is also discussed. (C) 2000 American Vacuum Society. [S0734-211X(00)12203-6]. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. EM kaixiu@uiuc.edu RI Gibson, Murray/E-5855-2013 OI Gibson, Murray/0000-0002-0807-6224 NR 9 TC 1 Z9 1 U1 0 U2 0 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 2000 VL 18 IS 3 BP 1299 EP 1305 DI 10.1116/1.591378 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 325AM UT WOS:000087654200032 ER PT J AU Coldren, CW Spruytte, SG Harris, JS Larson, MC AF Coldren, CW Spruytte, SG Harris, JS Larson, MC TI Group III nitride-arsenide long wavelength lasers grown by elemental source molecular beam epitaxy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 18th North American Conference on Molecular Beam Epitaxy CY OCT 10-13, 1999 CL BANFF, CANADA ID QUANTUM-WELL LASERS AB Elemental source molecular beam epitaxy was used to grow InGaNAs quantum well samples, edge-emitting laser diodes, and vertical-cavity laser diodes on GaAs substrates. The quantum well samples exhibited an as-grown room temperature photoluminescence Deaf; beyond 1310 nm which both increased dramatically in intensity and blueshifted with thermal annealing. Edge emitting laser diodes had threshold current densities as low as 450 and 750 A/cm(2) for single and triple quantum well active regions, respectively, and emitted light at 1210-1250 nm. The vertical cavity laser diodes emitted light at 1200 nm and had threshold current densities of 3 kA/cm(2) and efficiencies of 0.066 W/A. (C) 2000 American Vacuum Society. [S0734-211X(00)09603-7]. C1 Stanford Univ, Solid State & Photon Lab, Stanford, CA 94305 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Coldren, CW (reprint author), Stanford Univ, Solid State & Photon Lab, Via Ortega, Stanford, CA 94305 USA. NR 7 TC 10 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 2000 VL 18 IS 3 BP 1480 EP 1483 DI 10.1116/1.591408 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 325AM UT WOS:000087654200065 ER PT J AU Park, Y Cich, MJ Zhao, R Specht, P Weber, ER Stach, E Nozaki, S AF Park, Y Cich, MJ Zhao, R Specht, P Weber, ER Stach, E Nozaki, S TI Analysis of twin defects in GaAs(111)B molecular beam epitaxy growth SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 18th North American Conference on Molecular Beam Epitaxy CY OCT 10-13, 1999 CL BANFF, CANADA ID SURFACES AB The formation of twin is common during GaAs(111) and GaN(0001) molecular beam epitaxy (MBE) metalorganic chemical vapor deposition growth. A stacking fault in the zinc-blende (ZB)(111) direction can be described as an insertion of one monolayer of wurtzite structure, sandwiched between two ZB structures that have been rotated 60 degrees along the growth direction. GaAs(111)A/B MBE growth within typical growth temperature regimes is complicated by the formation of pyramidal structures and 60 degrees rotated twins, which are caused by faceting and stacking fault formation. Although previous studies have revealed much about the structure of these twins, a well-established simple nondestructive characterization method which allows the measurement of total aerial density of the twins does not exist at present. In this article, the twin density of AlCaAs layers grown on 1 degrees miscut GaAs(111)B substrates has been measured using high resolution x-ray diffraction, and characterized with a combination of Nomarski microscopy, atomic force microscopy, and transmission electron microscopy. These comparisons permit the relationship between the aerial twin density and the growth condition to be determined quantitatively. (C) 2000 American Vacuum Society. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. Univ Electrocommun, Dept Elect Engn, Tokyo, Japan. RP Park, Y (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RI Stach, Eric/D-8545-2011 OI Stach, Eric/0000-0002-3366-2153 NR 12 TC 20 Z9 20 U1 0 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 2000 VL 18 IS 3 BP 1566 EP 1571 DI 10.1116/1.591427 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 325AM UT WOS:000087654200086 ER PT J AU Klem, JF Blum, O Kurtz, SR Fritz, J Choquette, KD AF Klem, JF Blum, O Kurtz, SR Fritz, J Choquette, KD TI GaAsSb/InGaAs type-II quantum wells for long-wavelength lasers on GaAs substrates SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 18th North American Conference on Molecular Beam Epitaxy CY OCT 10-13, 1999 CL BANFF, CANADA ID MOLECULAR-BEAM EPITAXY; COMPOSITIONAL ABRUPTNESS; PHOTOLUMINESCENCE; INTERFACE AB We have investigated the propel ties of type-II bilayer quantum-well structures grown by molecular-beam epitaxy for use in long-wavelength lasers on GaAs substrates. Structures with layer strains acid thicknesses designed to be thermodynamically stable against dislocation formation exhibit room-temperature photoluminescence at wavelengths as long as 1.43 mu m. The photolumincscence emission wavelength is significantly affected by growth temperature and the sequence of layer growth (InGaAs/GaAsSb versus GaAsSb/InGaAs), suggesting that Sb and/or In segregation results in nonideal interfaces under certain growth conditions. At low-injection currents, double-heterostructure lasers with CaAsSb/InGaAs bilayer quantum-well active regions display electroluminescence at wavelengths comparable to those obtained in photoluminescence, but at higher currents the electroluminescence shifts to shorter wavelengths. Lasers have been obtained with threshold current densities of 120 A/cm(2) at 1.17 mu m, and 2.1 kA/cm(2) and 2.1 mu m. (C) 2000 American Vacuum Society. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Klem, JF (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 38 Z9 40 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 2000 VL 18 IS 3 BP 1605 EP 1608 DI 10.1116/1.591437 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 325AM UT WOS:000087654200096 ER PT J AU Seta, T Kono, K Martinez, D Chen, SY AF Seta, T Kono, K Martinez, D Chen, SY TI Lattice Boltzmann scheme for simulating two-phase flows SO JSME INTERNATIONAL JOURNAL SERIES B-FLUIDS AND THERMAL ENGINEERING LA English DT Article DE computational fluid dynamics; finite difference method; multi-phase flow; lattice Boltzmann method; pseudo-potential; van der Waals-Cahn-Hilliard fee energy ID GAS AUTOMATA; MODEL; EQUATION AB A finite difference lattice Boltzmann method (FDLBM) for two-phase flows pertinent to isothermal non-ideal fluids is proposed. This FDLBM introduces pseudopotential and recovers a full set of hydrodynamic equations for non-ideal fluid through the Chapman-Enskog expansion procedure. Numerical measurement of surface tension agrees well with theoretical predictions. Simulations of two-phase phenomena, including phase-transition and droplets collision are carried out, showing applicability of the model for two-phase flows. Finite difference Lattice Boltzmann method ensures numerical stability of the scheme. This LB model retains advantages of conventional LB methods such as a linear advection in the kinetic equation and parallel nature in computing. C1 Shizuoka Sangyo Univ, Shizuoka 4380043, Japan. Fuji Res Inst Corp, Computat Engn Grp, Chiyoda Ku, Tokyo 1010054, Japan. IBM Corp, TJ Watson Res Ctr, Yorktown Heights, NY 10598 USA. Univ Calif Los Alamos Natl Lab, IBM Corp, TJ Watson Res Ctr, Yorktown Heights, NY 10598 USA. RP Seta, T (reprint author), Shizuoka Sangyo Univ, 1572-1 Ohara, Shizuoka 4380043, Japan. RI Chen, Shiyi/A-3234-2010 NR 19 TC 10 Z9 10 U1 2 U2 7 PU JAPAN SOC MECHANICAL ENGINEERS PI TOKYO PA SHINANOMACHI-RENGAKAN BLDG, SHINANOMACHI 35, SHINJUKU-KU, TOKYO, 160-0016, JAPAN SN 1340-8054 J9 JSME INT J B-FLUID T JI JSME Int. J. Ser. B-Fluids Therm. Eng. PD MAY PY 2000 VL 43 IS 2 BP 305 EP 313 PG 9 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 326CB UT WOS:000087713400024 ER PT J AU Choquette, KD AF Choquette, KD TI Selectively oxidized VCSELs go single-mode SO LASER FOCUS WORLD LA English DT Article AB Manipulating modal gains or losses allows selectively oxidized vertical-cavity surface-emitting lasers to reach single-transverse-mode operation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Choquette, KD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU PENNWELL PUBL CO PI NASHUA PA 98 SPIT BROOK RD, NASHUA, NH 03062-2801 USA SN 0740-2511 J9 LASER FOCUS WORLD JI Laser Focus World PD MAY PY 2000 VL 36 IS 5 BP 251 EP + PG 3 WC Optics SC Optics GA 314ND UT WOS:000087061400053 ER PT J AU Lee, JH AF Lee, JH TI PURR-TURBO: A novel pulse sequence for longitudinal relaxographic imaging SO MAGNETIC RESONANCE IN MEDICINE LA English DT Article DE high field MRI; pulse sequences; T-1 measurement; relaxographic imaging ID RELAXATION-TIMES; SINGLE-SCAN; HUMAN BRAIN; ONE-SHOT; T-1; T1; OPTIMIZATION; MRI AB A novel pulse sequence based on a segmented phase-encoding scheme for measuring the longitudinal relaxation time (T-1) value of an NMR signal in an imaging context is introduced. This pulse sequence is a hybrid version of the "single-shot" and "one-shot" inversion recovery (IR) snapshot-FLASH methods. These are also known as "multipoint" IR techniques. The new sequence presented here collects multiple k-space rows at each time point during magnetization recovery, rather than the entire dataset (as in a "single-shot" method) or just one row (as in a "one-shot" method). Thus, it reduces the scanning time without significant sacrifice of the small sampling time advantage of the one-shot IR snapshot-FLASH methods. Furthermore, this approach does not require a high-performance gradient system. Here, we demonstrate that a single slice human brain (H2O)-H-1 T-1 map with a nominal in-plane resolution of less than (1 mm)(2) can be obtained at 4 T in about 4 min. Magn Reson Med 43: 773-777, 2000. Published 2000 Wiley-Liss, Inc. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Lee, JH (reprint author), Brookhaven Natl Lab, Dept Chem, Bldg 555A, Upton, NY 11973 USA. RI Lee, Jing-Huei/J-3978-2016 OI Lee, Jing-Huei/0000-0001-9921-7629 NR 20 TC 7 Z9 7 U1 1 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0740-3194 J9 MAGNET RESON MED JI Magn. Reson. Med. PD MAY PY 2000 VL 43 IS 5 BP 773 EP 777 DI 10.1002/(SICI)1522-2594(200005)43:5<773::AID-MRM23>3.0.CO;2-7 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 309VQ UT WOS:000086790300023 PM 10800046 ER PT J AU Vairavamurthy, MA Goldenberg, WS Shi, OY Khalid, S AF Vairavamurthy, MA Goldenberg, WS Shi, OY Khalid, S TI The interaction of hydrophilic thiols with cadmium: investigation with a simple model, 3-mercaptopropionic acid SO MARINE CHEMISTRY LA English DT Article DE hydrophilic thiols; cadmium; 3-mercaptopropionic acid ID MARINE-SEDIMENTS; PORE WATERS; SULFUR; COMPLEXATION; GLUTATHIONE; SPECIATION; MERCURY AB Environmental contamination by cadmium is widely recognized as a serious problem. All cadmium compounds are considered toxic and are regulated by the US Environmental Protection Agency. In organisms, thiols or organic sulfhydryl compounds are primarily involved in mobilizing and detoxifying cadmium through the formation of cadmium-thiol complexes inside the cell. This complexation is also of environmental importance because a variety of thiols are generated by biotic and abiotic processes in anaerobic environments, such as estuarine wetlands and coastal sediments, which have increasingly become the targets of metal pollution. We investigated the complexation of cadmium by 3-mercaptopropionic acid (MPA), using it as a simple model to better understand the potential pathways of cadmium transformations by hydrophilic thiols. Our results show that cadmium forms primarily 1:1 and 1:2 complexes with MPA in aqueous solutions at near-neutral pH values. While the dithio complex was highly soluble in water, the monothio complex rapidly precipitated from solution. Based on mass spectrometric and X-ray absorption spectroscopic data, we propose a cyclic, charge-neutralized structure for the monothio complex, and a linear ionic structure for the dithio complex. These results suggest that the type of complex formed is an important determinant of the mobility of cadmium. Published by Elsevier Science B.V.. C1 Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Vairavamurthy, MA (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. NR 23 TC 36 Z9 40 U1 3 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-4203 J9 MAR CHEM JI Mar. Chem. PD MAY PY 2000 VL 70 IS 1-3 BP 181 EP 189 DI 10.1016/S0304-4203(00)00023-2 PG 9 WC Chemistry, Multidisciplinary; Oceanography SC Chemistry; Oceanography GA 322XG UT WOS:000087534100015 ER PT J AU Edinger, EN Limmon, GV Jompa, J Widjatmoko, W Heikoop, JM Risk, MJ AF Edinger, EN Limmon, GV Jompa, J Widjatmoko, W Heikoop, JM Risk, MJ TI Normal coral growth rates on dying reefs: Are coral growth rates good indicators of reef health? SO MARINE POLLUTION BULLETIN LA English DT Review DE coral growth rates; eutrophication; sedimentation; coral reef health; bioindicators; Indonesia ID GREAT-BARRIER-REEF; CONTINENTAL-SHELF TRENDS; CALCIUM-CARBONATE BUDGET; STATES VIRGIN-ISLANDS; MONTASTREA-ANNULARIS; SKELETAL EXTENSION; FRINGING-REEF; MASSIVE PORITES; BUILDING CORALS; WEST-COAST AB Massive coral growth rates may be poor indicators of coral reef health where coral reefs are subject to combined eutrophication and sedimentation. Massive coral growth (vertical extension) rates on polluted reefs were not different from extension rates on unpolluted reefs, while live coral cover was low and bioerosion intensity high, leading to net reef erosion and death of the polluted reefs. These combined patterns of coral growth rates, coral cover and bioerosion were documented on reefs affected by land-based pollution in the Java Sea, South Sulawesi and Ambon, Indonesia. Acid-insoluble content in coral skeletons reflected land-based pollution stress on reefs more reliably than did coral extension rates. Coral skeletal density was lower on polluted Ja, a Sea reefs than on unpolluted reefs used as reference sites, but coral calcification rates,were not significantly different. The most eutrophied Java Sea reefs had net carbonate loss, indicating net reef erosion, while a fringing reef adjacent to mangroves and two unpolluted coral cays both had positive net carbonate production, Coral growth and reef growth were decoupled, in that coral growth rates did not reliably predict rates of reef accretion. The apparently paradoxical combination of normal to rapid coral growth and net reef erosion on polluted reefs illustrates the need for a whole-reef perspective on coral reef health. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Laurentian Univ, Dept Earth Sci, Sudbury, ON P3E 2C6, Canada. McMaster Univ, Sch Geog & Geol, Hamilton, ON L8S 4M1, Canada. McMaster Univ, Dept Biol, Hamilton, ON L8S 4K1, Canada. Pattimura Univ, Fac Fisheries & Marine Sci, Ambon, Indonesia. Hasanuddin Univ, Fac Fisheries & Marine Sci, Ujung Pandang, Indonesia. Diponegoro Univ, Fac Fisheries & Marine Sci, Semarang, Indonesia. Los Alamos Natl Lab, Div Earth & Environm Sci, Geol & Geochem Grp EES 1, Los Alamos, NM 87545 USA. RP Edinger, EN (reprint author), Laurentian Univ, Dept Earth Sci, Ramsey Lake Rd, Sudbury, ON P3E 2C6, Canada. EM edinger@nickel.laurentian.ca RI Heikoop, Jeffrey/C-1163-2011; kohki, sowa/D-2955-2011; OI Jompa, Jamaluddin/0000-0001-9740-333X NR 109 TC 145 Z9 151 U1 8 U2 66 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0025-326X EI 1879-3363 J9 MAR POLLUT BULL JI Mar. Pollut. Bull. PD MAY PY 2000 VL 40 IS 5 BP 404 EP 425 DI 10.1016/S0025-326X(99)00237-4 PG 22 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 321JF UT WOS:000087451800017 ER PT J AU Hou, PY AF Hou, PY TI Compositions at Al(2)O(3)/FeCrAl interfaces after high temperature oxidation SO MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION LA English DT Article ID OXIDE SCALE ADHERENCE; SULFUR SEGREGATION; INTERGRANULAR FRACTURE; SURFACE SEGREGATION; METAL INTERFACE; ALLOYS; ADHESION; STEELS; IRON; GROWTH AB Scanning Auger microscopy was used to study the chemistry of Al(2)O(3)/FeCrAl interfaces after the oxide scale had been removed in ultra high vacuum. Past studies that examined impurity segregation at these interfaces have shown a strong presence of sulfur, along with carbon and chromium enrichments. However, the relationships between these elements and the rate of their build up at the interface have not been addressed. This work examined many areas on several different specimens treated at various oxidation times, temperatures and with different cooling rates. Results showed that the carbon segregated during cooling. Interfacial sulfur and chromium concentrations varied at different locations that were not associated with apparent morphological differences, whether they were undulated ridges or valleys, voids, oxide-imprinted areas, alloy grain boundaries or different alloy grain faces. In most cases, there was a strong co-segregation of sulfur and chromium, although no sulfide particles were observed using scanning electron microscopy. At some locations, sulfur was found to segregate without the enrichment of chromium. The sulfur concentration could be low, as in the case of surface segregation in binary systems, or as high as being multi-layered. Results are analyzed in an attempt to recognize the structure of these segregants at the scale/alloy interface, such that their possible effect on scale adhesion may be better understood. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Hou, PY (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 38 TC 26 Z9 27 U1 2 U2 5 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0947-5117 J9 MATER CORROS JI Mater. Corros. PD MAY PY 2000 VL 51 IS 5 BP 329 EP 337 DI 10.1002/(SICI)1521-4176(200005)51:5<329::AID-MACO329>3.0.CO;2-K PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 321JP UT WOS:000087452600007 ER PT J AU Sugama, T Weber, L Brothers, LE AF Sugama, T Weber, L Brothers, LE TI Sodium-polyphosphate-modified fly ash/calcium aluminate blend cement: durability in wet, harsh geothermal environments SO MATERIALS LETTERS LA English DT Article DE sodium-polyphosphate-modified fly ash/calcium aluminate blend cement; hydroxyapatite; analcime ID SILICATE-GLASSES AB To assess the durability of sodium-polyphosphate-modified fly ash/calcium aluminate blend (SFCB) cement, which was used to complete geothermal wells in Indonesia, the cement specimens were exposed for up to 7 months in autoclave containing a simulated geothermal brine with 20,000 ppm CO2 and 400 ppm H2S at 280 degrees C, Hydrothermal reactions between sodium polyphosphate (NaP) and fly ash or calcium aluminate cement (CAC) generated two major crystalline phases, hydroxyapatite (HOAp) and analcime (AN), which were responsible for developing a densified microstructure in cement bodies, offering their ultimate compressive strength. The AN phase was susceptible to a reaction with CO2, transforming it into the cancrinite (CAN) phase. The AN --> CAN phase transition continuously took place during exposure between 7 days and 4 months. This phase transition caused the alteration of a dense microtexture into a porous one, thereby resulting in some loss of strength. However, once the conversion of AN into CAN neared completion, there was no further significant change in compressive strength. After 7 months of exposure, the phase composition of cement consisted of HOAp and CAN as the major phases, and AN as the minor one. No decomposition of the cement was observed, nor was there any carbonation-caused erosion, suggesting that the SFCB cement has an excellent durability in a hostile geothermal environment. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Appl Sci, Div Mat & Chem Sci, Upton, NY 11973 USA. UNOCAL Corp, Sugarland, TX 77478 USA. Halliburton Energy Serv, Duncan, OK 73536 USA. RP Sugama, T (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Div Mat & Chem Sci, Bldg 526,12 N 6th St, Upton, NY 11973 USA. NR 9 TC 9 Z9 9 U1 2 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-577X J9 MATER LETT JI Mater. Lett. PD MAY PY 2000 VL 44 IS 1 BP 45 EP 53 DI 10.1016/S0167-577X(00)00002-1 PG 9 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 315CF UT WOS:000087094500010 ER PT J AU Ralph, D Wright, SJ AF Ralph, D Wright, SJ TI Superlinear convergence of an interior-point method despite dependent constraints SO MATHEMATICS OF OPERATIONS RESEARCH LA English DT Article DE interior-point method; monotone variational inequalities; superlinear convergence ID COMPLEMENTARITY-PROBLEMS; ALGORITHMS AB We show that an interior-point method for monotone variational inequalities exhibits superlinear convergence provided that all the standard assumptions hold except for the well-known assumption that the Jacobian of the active constraints has full rank at the solution. We show that superlinear convergence occurs even when the constant-rank condition on the Jacobian assumed in an earlier work does not hold. C1 Univ Cambridge, Judge Inst Management Studies, Cambridge CB2 1AG, England. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Ralph, D (reprint author), Univ Cambridge, Judge Inst Management Studies, Trumpington St, Cambridge CB2 1AG, England. NR 15 TC 17 Z9 18 U1 0 U2 1 PU INST OPERATIONS RESEARCH MANAGEMENT SCIENCES PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2909 USA SN 0364-765X J9 MATH OPER RES JI Math. Oper. Res. PD MAY PY 2000 VL 25 IS 2 BP 179 EP 194 DI 10.1287/moor.25.2.179.12227 PG 16 WC Operations Research & Management Science; Mathematics, Applied SC Operations Research & Management Science; Mathematics GA 328AN UT WOS:000087826800002 ER PT J AU Gall, K Horstemeyer, M McDowell, DL Fan, JH AF Gall, K Horstemeyer, M McDowell, DL Fan, JH TI Finite element analysis of the stress distributions near damaged Si particle clusters in cast Al-Si alloys SO MECHANICS OF MATERIALS LA English DT Article ID FATIGUE-CRACK-GROWTH; ALUMINUM-ALLOY; FRACTURE-BEHAVIOR; SILICON PARTICLES; TOUGHNESS AB The finite element method is used to study the effects of particle cluster morphology on the fracture and debonding of silicon particles embedded in an Al-1%Si matrix subjected to tensile-compressive cyclic loading conditions. Representative of an actual cast A-Si alloy, clusters of silicon inclusions (4-8 particles) are considered rather than a single isolated inclusion or an infinite periodic array of inclusions. The silicon particles are modeled with a linear-elastic constitutive relationship and the matrix material is modeled using an internal state variable cyclic plasticity model fitted to experimental data on matrix material. A total of seven parameters are varied to create 16 idealized microstructures: relative particle size, shape, spacing, configuration, alignment, grouping and matrix microporosity. A two-level design of experiment (DOE) methodology is used to screen the relative importance of the seven parameters on the fracture and debonding of the silicon particles. The results of the study demonstrate that particle shape and alignment are undoubtedly the most dominant parameters influencing initial particle fracture and debonding. Particle debonding results in a local intensification of stresses in the Al-1%Si matrix that is significantly larger than that due to particle fracture. The local stress fields after particle fracture are primarily concentrated within the broken particle halves. After the fracture of several particles within a cluster, the spacing between adjacent particles enters as a second-order effect. When several particles within a cluster debond, the spacing between adjacent particles enters as a dominant effect due to the large local stress intensification in the surrounding Al-1%Si matrix. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Solid & Mat Mech Dept, Ctr Mat Sci & Engn, Livermore, CA 94550 USA. Georgia Inst Technol, GWW Sch Mech Engn, Atlanta, GA 30332 USA. RP Gall, K (reprint author), Sandia Natl Labs, Solid & Mat Mech Dept, Ctr Mat Sci & Engn, 7011 East Ave,MS 9405, Livermore, CA 94550 USA. OI Horstemeyer, Mark/0000-0003-4230-0063 NR 33 TC 70 Z9 75 U1 1 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6636 J9 MECH MATER JI Mech. Mater. PD MAY PY 2000 VL 32 IS 5 BP 277 EP 301 DI 10.1016/S0167-6636(00)00003-X PG 25 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA 301YB UT WOS:000086337200002 ER PT J AU Eichler, J Liebetruth, J London, RA Ziegenhagen, L AF Eichler, J Liebetruth, J London, RA Ziegenhagen, L TI Temperature distribution for combined laser hyperthermia-photodynamic therapy in the esophagus SO MEDICAL ENGINEERING & PHYSICS LA English DT Article DE laser; hyperthermia; photodynamic therapy; cancer; esophagus ID TISSUE; COMBINATION; CANCER; SAFE AB In recent years photodynamic laser therapy (PDT) has been tested in animal and clinical studies for treatment of esophageal cancer. In several animal experiments a synergistic effect was found by simultaneously applying PDT and hyperthermia (HT). In this paper an optical fibre system is described which can be used in the esophagus for combined PDT with a 1 W dye laser and HT with a 15 W Nd:YAG laser. A phantom was built simulating the geometry of the esophagus using cow muscle. The spatial temperature field during HT was measured Versus irradiation time. The results were compared with calculations using a coupled Monte Carlo laser transport/finite difference heat transport model using the LATIS computer program. Measurements and calculations yield a realistic description of the temperature distribution during HT under various experimental conditions. The LATIS program allows the prediction of the effects of blood perfusion for in vivo situations. The results show that perfusion has considerable influence on the temperature field, reducing the effective depth in tissue for HT. (C) 2000 IPEM. Published by Elsevier Science Ltd, All rights reserved. C1 Univ Appl Sci, TFH, D-13347 Berlin, Germany. Humboldt Univ, Charite Berlin, D-10000 Berlin, Germany. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Eichler, J (reprint author), Univ Appl Sci, TFH, Seestr 64, D-13347 Berlin, Germany. NR 12 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1350-4533 J9 MED ENG PHYS JI Med. Eng. Phys. PD MAY PY 2000 VL 22 IS 4 BP 307 EP 312 DI 10.1016/S1350-4533(00)00037-0 PG 6 WC Engineering, Biomedical SC Engineering GA 360MV UT WOS:000089672500008 PM 11018463 ER PT J AU von Wittenau, AES Bergstrom, PM Cox, LJ AF von Wittenau, AES Bergstrom, PM Cox, LJ TI Patient-dependent beam-modifier physics in Monte Carlo photon dose calculations SO MEDICAL PHYSICS LA English DT Article DE Monte Carlo; photon dose calculation; photon teletherapy; radiation treatment planning ID X-RAY-BEAMS; ELECTRON CONTAMINATION; BUILDUP REGION; QUALITY ASSURANCE; SCATTERED PHOTONS; RADIOTHERAPY; DOSIMETRY; RADIATION; SURFACE; COLLIMATORS AB Model pencil-beam on slab calculations are used as well as a series of detailed calculations of photon and electron output from commercial accelerators to quantify level(s) of physics required for the Monte Carlo transport of photons and electrons in treatment-dependent beam modifiers, such as jaws, wedges, blocks, and multileaf collimators, in photon teletherapy dose calculations. The physics approximations investigated comprise (1) not tracking particles below a given kinetic energy, (2) continuing to track particles, but performing simplified collision physics, particularly in handling secondary particle production, and (3) not tracking particles in specific spatial regions. Figures-of-merit needed to estimate the effects of these approximations are developed, and these estimates are compared with full-physics Monte Carlo calculations of the contribution of the collimating jaws to the on-axis depth-dose curve in a water phantom. These figures of merit are next used to evaluate various approximations used in coupled photon/electron physics in beam modifiers. Approximations for tracking electrons in air are then evaluated. It is found that knowledge of the materials used for beam modifiers, of the energies of the photon beams used, as well as of the length scales typically found in photon teletherapy plans, allows a number of simplifying approximations to be made in the Monte Carlo transport of secondary particles from the accelerator head and beam modifiers to the isocenter plane. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP von Wittenau, AES (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 60 TC 24 Z9 24 U1 0 U2 1 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 MAY PY 2000 VL 27 IS 5 BP 935 EP 947 DI 10.1118/1.598959 PG 13 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 317EA UT WOS:000087212200014 PM 10841396 ER PT J AU Stabin, MG Konijnenberg, M Knapp, FF Spencer, RH AF Stabin, MG Konijnenberg, M Knapp, FF Spencer, RH TI Monte Carlo modeling of radiation dose distributions in intravascular radiation therapy SO MEDICAL PHYSICS LA English DT Article DE dosimetry; intravascular radiation therapy; radiation safety ID INHIBITS NEOINTIMA FORMATION; ARTERY BALLOON INJURY; CORONARY-ARTERIES; RESTENOSIS; ANGIOPLASTY; SWINE AB Radiation dose distributions are developed for balloon and wire sources of radioactivity within coronary arteries. The Monte Carlo codes MCNP 4B and EGS4 were used to calculate dose distributions for photons and electrons at discrete energies around such sources, with and without the presence of a high-density atherosclerotic plaque. An interactive computer program was developed which then calculates dose distributions for many radionuclides by applying the emission spectra to the discrete energy grids calculated by the Monte Carlo codes, weighting appropriately for electron energy and abundance. Results for Re-186 and Re-188 balloon sources are shown in comparison to an Ir-192 wire source. The program provides dose distributions as well as estimates of activity levels needed to deliver prescribed doses to the vessel wall at selected distances from the lumen in a selected time interval. In addition, dose calculations are presented in this paper for other organs in the body, from photon radiation as well as from possible loss of liquid activity into the bloodstream in the case of a balloon rupture. These results, especially the interactive computer program permitting easy comparison of various radionuclides and their physical characteristics, will greatly facilitate the comparison process and aid in the selection of the best candidate(s) fur clinical use. (C) 2000 American Association of Physicists in Medicine. [S0094-2405(00)02005-8]. C1 Univ Fed Pernambuco, Recife, PE, Brazil. Mallickrodt BV, Petten, Netherlands. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Tennessee, Knoxville, TN USA. RP Stabin, MG (reprint author), Univ Fed Pernambuco, Recife, PE, Brazil. NR 21 TC 21 Z9 21 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD MAY PY 2000 VL 27 IS 5 BP 1086 EP 1092 DI 10.1118/1.598973 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 317EA UT WOS:000087212200031 PM 10841413 ER PT J AU Kennel, SJ Davis, IA Branning, J Pan, HJ Kabalka, GW Paulus, MJ AF Kennel, SJ Davis, IA Branning, J Pan, HJ Kabalka, GW Paulus, MJ TI High resolution computed tomography and MRI for monitoring lung tumor growth in mice undergoing radioimmunotherapy: Correlation with histology SO MEDICAL PHYSICS LA English DT Article DE lung tumors; mice; computed tomography; radioimmunotherapy; histology ID BRONCHOGENIC-CARCINOMA; CHEST-WALL; CT; MICROSCOPY; RECONSTRUCTION; ONCOLOGY; INVASION; BI-213; MODEL AB A model lung tumor system has been developed in mice for the evaluation of vascular targeted radioimmunotherapy. In this model, EMT-6 mammary carcinoma tumors growing in the lung are treated with Bi-213, an alpha particle emitter, which is targeted to lung blood vessels using a monoclonal antibody. Smaller tumors (< 100 mu m in diameter) are cured, but larger tumors undergo a period of regression and then regrow and ultimately prove lethal. The goal of this work was to determine if external imaging with MRI or CT could be used routinely to monitor the growth/regression of lung tumors in live mice. To attempt to evaluate individual tumors in vivo, animals were initially imaged with magnetic resonance imaging (MRI). High resolution MRI images could be obtained only after sacrifice when lungs were not moving. In contrast, high resolution computed tomography (CT) produced evaluable images from anesthetized animals. Serial CT images (up to 5/animal) were collected over a 17 day period of tumor growth and treatment. When tumored animals became moribund, animals were sacrificed and lungs were inflated with fixative, embedded in paraffin, and then sectioned serially to compare the detection of tumors by high resolution CT with detection by histology. CT proved most useful in detecting lung tumors located in the hilar area and least useful in detecting serosal surface and anterior lobe tumor foci. Overall, CT images of live animals revealed tumors in similar to 2/3 of cases detected in histologic serial sections when relatively few tumors were present per lung. Detection of lesions and their resolution post therapy were complicated due to residual hemorrhagic, regressing tumor nodules and the development of lung edema both of which appeared as high density areas in the CT scans. We conclude that the microCT method used could identify some lung tumors as small as 100 mu m in diameter; however, no concrete evaluation of therapy induced regression of the tumors could be made with CT analyses alone. (C) 2000 American Association of Physicists in Medicine. [S0094-2405(00)02505-0]. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Instrumentat & Controls, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37920 USA. RP Kennel, SJ (reprint author), Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. NR 32 TC 65 Z9 65 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD MAY PY 2000 VL 27 IS 5 BP 1101 EP 1107 DI 10.1118/1.598974 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 317EA UT WOS:000087212200033 PM 10841415 ER PT J AU Cambel, V Karapetrov, G Elias, P Hasenohrl, S Kwok, WK Krause, J Manka, J AF Cambel, V Karapetrov, G Elias, P Hasenohrl, S Kwok, WK Krause, J Manka, J TI Approaching the pT range with a 2DEG InGaAs/InP Hall sensor at 77 K SO MICROELECTRONIC ENGINEERING LA English DT Article; Proceedings Paper CT 3rd International Conference on Low Dimensional Structures and Devices (LDSD 99) CY SEP 15-17, 1999 CL ANTALYA, TURKEY DE 2DEG Hall sensor; InGaAs/InP heterostructure; 1/f noise ID NOISE SOURCES AB The noise of two-dimensional electron gas InGaAs/InP Hall sensors of various dimensions was studied. In the first part of the work we show that for large-scale sensors ( > 0.2 mm linear dimension) at 77 K and at 1 kHz, a sensitivity better then 1 nT can be achieved. The second part of present work deals with the noise measurements of 2 and 10 mu m sensors dependent on bias current, frequency, applied magnetic field and temperature. It was found that the low-frequency noise of the 10 mu m sensor rapidly increased for applied magnetic field, but the noise of the 2 mu m sensor is a complicated function of temperature and magnetic field, for low temperatures and fields 1-3 T is the low-frequency noise of the sensor suppressed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Slovak Acad Sci, Inst Elect Engn, Bratislava 84239, Slovakia. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Res Ctr Julich, Julich, Germany. Slovak Acad Sci, Inst Measurement Sci, Bratislava, Slovakia. RP Cambel, V (reprint author), Slovak Acad Sci, Inst Elect Engn, Bratislava 84239, Slovakia. RI Hasenohrl, Stanislav/J-8945-2012; Karapetrov, Goran/C-2840-2008 OI Karapetrov, Goran/0000-0003-1113-0137 NR 7 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9317 J9 MICROELECTRON ENG JI Microelectron. Eng. PD MAY PY 2000 VL 51-2 BP 333 EP 342 DI 10.1016/S0167-9317(99)00491-8 PG 10 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Optics; Physics, Applied SC Engineering; Science & Technology - Other Topics; Optics; Physics GA 320ZY UT WOS:000087431500042 ER PT J AU Mikrajuddin Shi, FG Nieh, TG Okuyama, K AF Mikrajuddin Shi, FG Nieh, TG Okuyama, K TI Metal-to-semiconductor transition in nanocrystals: size and temperature dependence SO MICROELECTRONICS JOURNAL LA English DT Article DE nanocrystal; electrical conductivity; metal-to-semiconductor transition; size dependence; temperature dependence ID ELECTRONIC STATES; POROUS SILICON; CLUSTERS; NANOPARTICLES; PARTICLES AB The electrical conductivity of nanocrystals is investigated by using a hybrid approach that treats the electronic structure of a nanocrystal quantum mechanically, and the transport of electrons semiclassically. The simplicity and its analytical nature of the present approach allow one to gain unique insights into the size dependent metal-to-semiconductor transition in nanocrystals. The analytical expression for the electrical conductivity of nanocrystals as a function of size and temperature demonstrates that for a given temperature, there is a critical size at which the metal-to-semiconductor transition occurs which decreases with increasing temperature. For a given sized nanocrystal, a critical temperature for the occurrence of the metal-to-semiconductor transition is also demonstrated. The critical transition temperature is found to decrease with the increasing nanocrystal size. Although the predicted size and the temperature dependence of electrical conductivity for nanocrystals is shown to be remarkably consistent with the recent experimental observations, the effect of the size distribution of nanocrystals must be further investigated. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Hiroshima Univ, Fac Engn, Dept Chem Engn, Higashihiroshima 7398527, Japan. Univ Calif Irvine, Sch Engn, Irvine, CA 92697 USA. Lawrence Livermore Natl Lab, Chem & Mat Div, Livermore, CA 94551 USA. RP Hiroshima Univ, Fac Engn, Dept Chem Engn, Higashihiroshima 7398527, Japan. EM okuyama@ipc.hiroshima-u.ac.jp RI Nieh, Tai-Gang/G-5912-2011; okuyama, kikuo/F-6092-2010 OI Nieh, Tai-Gang/0000-0002-2814-3746; NR 26 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0026-2692 EI 1879-2391 J9 MICROELECTRON J JI Microelectron. J. PD MAY PY 2000 VL 31 IS 5 BP 343 EP 351 PG 9 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology SC Engineering; Science & Technology - Other Topics GA 310KA UT WOS:000086824000005 ER PT J AU Shin, Y Zemanian, TS Fryxell, GE Wang, LQ Liu, J AF Shin, Y Zemanian, TS Fryxell, GE Wang, LQ Liu, J TI Supercritical processing of functionalized size selective microporous materials SO MICROPOROUS AND MESOPOROUS MATERIALS LA English DT Article DE catalytic; microporous; selective; silanation; supercritical ID MOLECULAR-SIEVES; MESOPOROUS MATERIALS; CATALYSTS; ZEOLITES; METAL; MONOLAYERS AB A supercritical fluid silanation process is applied to effectively functionalize commercial microporous materials without blocking the pore channels. In this approach, supercritical carbon dioxide (SCCO2) is used to deposit mercaptopropyl silane into the microporosity of zeolite beta. The thiol group was subsequently oxidized into sulfonic acid. The size selective catalytic properties of the SCCO2 modified zeolite compare well with similar materials prepared by an in situ silanation process reported by Jones et al. The active functional groups were delivered to the internal pore surface of the microporous material and remain accessible to molecules that can enter the pore channels. The supercritical process provides an alternative approach to functionalize microporous materials because of the enhanced diffusivity of the functional molecules in the micropore channels and accelerated reaction kinetics. Furthermore, the supercritical process simplifies the materials preparation and may open up new opportunities for commercial zeolites. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99353 USA. RP Liu, J (reprint author), Pacific NW Natl Lab, Richland, WA 99353 USA. NR 23 TC 38 Z9 38 U1 0 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-1811 J9 MICROPOR MESOPOR MAT JI Microporous Mesoporous Mat. PD MAY PY 2000 VL 37 IS 1-2 BP 49 EP 56 DI 10.1016/S1387-1811(99)00192-4 PG 8 WC Chemistry, Applied; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 311FP UT WOS:000086874300006 ER PT J AU Volkl, E AF Volkl, E TI Live electron holography: Window to the phase world SO MICROSCOPY AND MICROANALYSIS LA English DT Article DE live electron holography; electron holography; live phase image; phase image; transfer function; surface display; live reconstruction; reconstruction ID RECONSTRUCTION AB While the idea of electron holography has been around for over 50 years, the technology necessary to establish a window to the phase world is only now becoming available. This is the first report of an all digital system for displaying the image phase continuously and live, instead of looking at one frame at a time after initiation of the reconstruction procedure. The technical requirements, including the necessary image processing steps which differ from the standard reconstruction procedure for single frame holograms, will, be discussed, and current lime demands for image acquisition and the different elements of image processing will be laid out. The modified requirements for continuous, live processing will be discussed in detail, and images obtained in the live mode will be shown. C1 Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Volkl, E (reprint author), Oak Ridge Natl Lab, High Temp Mat Lab, 1 Bethel Valley Rd, Oak Ridge, TN 37831 USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1431-9276 J9 MICROSC MICROANAL JI Microsc. microanal. PD MAY-JUN PY 2000 VL 6 IS 3 BP 211 EP 217 PG 7 WC Materials Science, Multidisciplinary; Microscopy SC Materials Science; Microscopy GA 309VR UT WOS:000086790400003 ER PT J AU Stewart, PL Cary, RB Peterson, SR Chiu, CY AF Stewart, PL Cary, RB Peterson, SR Chiu, CY TI Digitally collected cryo-electron micrographs for single particle reconstruction SO MICROSCOPY RESEARCH AND TECHNIQUE LA English DT Article DE adenovirus; DNA-dependent protein kinase; image reconstruction; resolution; slow-scan CCD camera ID CRYOELECTRON MICROSCOPY; ANGSTROM RESOLUTION; CATALYTIC SUBUNIT; PROTEIN-KINASE; ADENOVIRUS; CRYOMICROSCOPY; CAMERAS AB Several advantages and disadvantages have been cited for image collection with a slow-scan CCD camera. Here we explore its use for cryo-EM single particle reconstruction and present two practical examples. The icosahedral adenovirus (Ad) type 2 (similar to 150 MDa) was reconstructed from 396 particle images. The Fourier shell correlation (FSC) 0.5 threshold and the Fourier shell phase residual (FSPR) 45 degrees criterion yielded 17 Angstrom A resolution for the ordered viral capsid. Visual comparison with the filtered Ad2 crystallographic hexon confirmed a resolution range of 15-17 Angstrom. The asymmetric DNA-PKcs protein (470 kDa) was reconstructed from 9,473 particle images, using a previously published reconstruction based on class-sum images as an orientational search model [Chiu et al. (1998) J. Mol. Biol. 284:1075-1081]. FSC and FSPR methods yielded 17 Angstrom resolution for the new DNA-PKcs reconstruction, indicating a small but noticeable improvement over that of the class-sum based reconstruction. Despite the lack of symmetry for DNA-PKcs and its lower image contrast compared to Ad2 (0.8% vs. 2.5%), the same resolution was obtained for both particles by averaging significantly more DNA-PKcs images. Use of the CCD camera enables the microscopist to adjust the electron beam strength interactively and thereby maximize the image contrast for beam sensitive samples. On-line Fourier transformation also allows routine monitoring of drift and astigmatism during image collection, resulting in a high percentage of micrographs suitable for image processing. In conclusion, our results show that digital image collection with the YAG-scintillator slow-scan CCD camera is a viable approach for 3D reconstruction of both symmetric and asymmetric particles. Microsc. Res. Tech. 49:224-232, 2000. (C) 2000 Wiley-Liss, Inc. C1 Univ Calif Los Angeles, Sch Med, Dept Mol & Med Pharmacol, Los Angeles, CA 90095 USA. Univ Calif Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM 87545 USA. Icos Corp, Bothell, WA 98021 USA. RP Stewart, PL (reprint author), Univ Calif Los Angeles, Sch Med, Dept Mol & Med Pharmacol, A-324 CIBI,Box 951770, Los Angeles, CA 90095 USA. OI Chiu, Charles/0000-0003-2915-2094 FU NIAID NIH HHS [AI42929]; NIGMS NIH HHS [GM08042] NR 17 TC 16 Z9 17 U1 1 U2 6 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1059-910X J9 MICROSC RES TECHNIQ JI Microsc. Res. Tech. PD MAY 1 PY 2000 VL 49 IS 3 BP 224 EP 232 DI 10.1002/(SICI)1097-0029(20000501)49:3<224::AID-JEMT2>3.0.CO;2-0 PG 9 WC Anatomy & Morphology; Biology; Microscopy SC Anatomy & Morphology; Life Sciences & Biomedicine - Other Topics; Microscopy GA 312YP UT WOS:000086971800002 PM 10816264 ER PT J AU Noah, KS Olson, GJ AF Noah, KS Olson, GJ TI Biochemical removal of HAP precursors from coal - INEEL slurry column testing SO MINERALS & METALLURGICAL PROCESSING LA English DT Article DE biobeneficiation; coal cleaning; HAP precursor removal; slurry column; pyrite removal; biooxidation ID TRACE-ELEMENTS; BENEFICIATION AB A combined physical/biochemical process for the precombustion removal of 13 inorganic hazardous air pollutant (HAP) precursors, i.e., Sb, As, Be, Cd, Cr, CI, Co, F, Pb, Hg, Mn, Ni and Se, from coal was tested. Biochemical processes for removal of HAP precursors from coal potentially offer advantages of deeper cleaning, more specificity, and less coal loss. The slurry column is a second-generation process for the beneficiation of fine (60-mesh x 10-mu m) coal by a combination of physical separation of mineral matter and biooxidation of pyrite. Sixty-seven percent removal of pyrite from a 60-mesh Pittsburgh #8 coal was achieved at a 35% (w/w) slurry concentration and a five-day reactor residence time. Ninety per-cent of the hearing value of the feed coal was recovered. Among the HAP precursors of most concern, over half of the Se, As and Hg were removed from the feed coal. From 40% to 70% of most HAP precursors were removed from the feed coal. Hg in the feed coal was reduced from 0.12 to 0.054 mu g in the product coal, while waste coal contained 0.24 mu g/g. C1 Idaho Natl Lab, Dept Biotechnol, Idaho Falls, ID USA. Little Bear Labs Inc, Golden, CO USA. RP Noah, KS (reprint author), Idaho Natl Lab, Dept Biotechnol, Idaho Falls, ID USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU SOC MINING METALLURGY EXPLORATION INC PI LITTLETON PA 8307 SHAFFER PARKWAY, LITTLETON, CO 80127 USA SN 0747-9182 J9 MINER METALL PROC JI Miner. Metall. Process. PD MAY PY 2000 VL 17 IS 2 BP 77 EP 84 PG 8 WC Metallurgy & Metallurgical Engineering; Mining & Mineral Processing SC Metallurgy & Metallurgical Engineering; Mining & Mineral Processing GA 315CG UT WOS:000087094600002 ER PT J AU Thompson, DN Sayer, RL Noah, KS AF Thompson, DN Sayer, RL Noah, KS TI Sawdust-supported passive bioremediation of western United States acid rock drainage in engineered wetland systems SO MINERALS & METALLURGICAL PROCESSING LA English DT Article DE bioremediation; acid rock drainage; sawdust; lignocellulose; sulfate-reducing bacteria; wetland technology AB Economical remediation of acid rock drainage (ARD) at secluded high-altitude western ore mines is difficult given the current treatment technology. Several passive-engineered systems that are based on wetland technology were tested in the laboratory with three western ore mine ARDs (Co, Cu and Fe mines) and with a copper leachate effluent. These systems used well-weathered lodgepole pine sawdust as the sole carbon source and mud from a pond at one of the mine sites as the source of sulfate-reducing bacteria (SRB). Simple one pass flow-through systems removed 44% to 99% of the various heavy metals from the Co and Cu mine ARDs and increased the pH from 3 to 7 after 28 days of SRB acclimation with a five-day residence time. Carbohydrate utilization rates were generally low: except for one 437-day run, which consumed 25%, 30% and 21 % of the cellulose, hemicellulose and lignin, respectively. Initial pH, amounts of toxic heavy metals and the degree of predegradation of the sawdust were found to significantly affect both remediation potential and acclimation time. Engineered SRB systems, alone or in combination with other passive technologies, offer promise for the economical remediation of western US ore mine ARDs. C1 Idaho Natl Lab, Dept Biotechnol, Idaho Falls, ID USA. RP Thompson, DN (reprint author), Idaho Natl Lab, Dept Biotechnol, Idaho Falls, ID USA. NR 29 TC 2 Z9 2 U1 1 U2 3 PU SOC MINING METALLURGY EXPLORATION INC PI LITTLETON PA 8307 SHAFFER PARKWAY, LITTLETON, CO 80127 USA SN 0747-9182 J9 MINER METALL PROC JI Miner. Metall. Process. PD MAY PY 2000 VL 17 IS 2 BP 96 EP 104 PG 9 WC Metallurgy & Metallurgical Engineering; Mining & Mineral Processing SC Metallurgy & Metallurgical Engineering; Mining & Mineral Processing GA 315CG UT WOS:000087094600004 ER PT J AU Nicholson, DMC Sterne, PA Swihart, JC Tran, J Wang, Y AF Nicholson, DMC Sterne, PA Swihart, JC Tran, J Wang, Y TI Electron and positron states in amorphous Ni0.4Pd0.4P0.2 SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article; Proceedings Paper CT Workshop on Thermodynamic and Structural Properties of Alloy Materials CY JUN 20-24, 1999 CL ORANJESTAD, NETHERLANDS SP Army Res Off ID METALLIC GLASSES; ALLOYS; DENSITY; SPECTRA; ORDER AB We performed local density calculations of the electronic and positron states for a 300-atom model of bulk amorphous Ni0.4Pd0.4P0.2. The procedure for constructing the model and the resulting distribution of bond angles and free volume are described. Comparisons are made to experiment and to models of amorphous Ni0.8P0.2. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Luther Coll, Dept Phys, Decora, IA 52101 USA. Pittsburgh Supercomp Ctr, Pittsburgh, PA 15213 USA. RP Nicholson, DMC (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 19 TC 2 Z9 2 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD MAY PY 2000 VL 8 IS 3 BP 261 EP 268 DI 10.1088/0965-0393/8/3/306 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 323LU UT WOS:000087567500007 ER PT J AU Trenkler, J Abe, H Wochner, P Haeffner, D Bai, J Carstanjen, HD Moss, SC AF Trenkler, J Abe, H Wochner, P Haeffner, D Bai, J Carstanjen, HD Moss, SC TI Change from a bulk discontinuous phase transition in V2H to a continuous transition in a defective near-surface skin layer SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article; Proceedings Paper CT Workshop on Thermodynamic and Structural Properties of Alloy Materials CY JUN 20-24, 1999 CL ORANJESTAD, NETHERLANDS SP Army Res Off ID QUENCHED RANDOMNESS; SYSTEMS; FIELD; ORDER; DISORDER; ND4CL AB Using high- and low-energy x-ray scattering techniques, we have studied the effect of defects on the beta(1)-beta(2) phase transition in V2H. Since we earlier observed two length scales in this crystal, we focus here exclusively on either the pure bulk or the defective skin layer, which is several micrometres thick. While we found a strong and narrow discontinuous transition in the bulk, there is a continuous transition in this defective skin layer in which the mosaic spread decreases with depth. We suggest that the strain field associated with the change of the mosaic spread most likely prompts the conversion of the order of the phase transition. C1 Univ Houston, Dept Phys, Houston, TX 77204 USA. Max Planck Inst Met Forsch, D-70569 Stuttgart, Germany. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Trenkler, J (reprint author), Max Planck Inst Met Forsch, D-70569 Stuttgart, Germany. RI Bai, Jianming/O-5005-2015 NR 29 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD MAY PY 2000 VL 8 IS 3 BP 269 EP 275 DI 10.1088/0965-0393/8/3/307 PG 7 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 323LU UT WOS:000087567500008 ER PT J AU Asta, M Ozolins, V Hoyt, JJ AF Asta, M Ozolins, V Hoyt, JJ TI The energetics of surface-alloy formation: an embedded-atom-method, second-order-expansion study SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article; Proceedings Paper CT Workshop on Thermodynamic and Structural Properties of Alloy Materials CY JUN 20-24, 1999 CL ORANJESTAD, NETHERLANDS SP Army Res Off ID PERIODIC DOMAIN-STRUCTURES; SOLID-SOLUTIONS; METALS; CU; NI; AG; AU AB Chemical ordering and clustering instabilities in alloys are governed by the Fourier transform of the effective pair interactions, V(k). We make use of a second-order-expansion formalism, based upon embedded-atom-method interatomic potentials, to calculate chemical and elastic contributions to V(k) for monolayer surface alloys on single-crystal substrates. It is demonstrated that the elastic contribution to V(k) is characterized by a finite slope at the origin, consistent with continuum models which predict that V(k) infinity -\ k \ for small wavevectors. As a consequence, the global minimum in V(lc) always occurs at finite k, and therefore compositional instabilities in ultrathin surface-alloy films are generally of an ordering las opposed to clustering, k = 0) type. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RI Ozolins, Vidvuds/D-4578-2009 NR 16 TC 0 Z9 0 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 EI 1361-651X J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD MAY PY 2000 VL 8 IS 3 BP 287 EP 293 DI 10.1088/0965-0393/8/3/309 PG 7 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 323LU UT WOS:000087567500010 ER PT J AU Aguilar, JF Ravelo, R Baskes, MI AF Aguilar, JF Ravelo, R Baskes, MI TI Morphology and dynamics of 2D Sn-Cu alloys on (100) and (111) Cu surfaces SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID EMBEDDED-ATOM METHOD; METALS; IMPURITIES; INTERFACES; CU(111); TIN AB We have performed calculations of Sn deposition on Cu(111) and Cu(100) surfaces. The atomic interactions are described by modified embedded atom method (MEAM) potentials. This is a modification of the embedded atom method (EAM) to include higher moments in the electron density. We find that at low coverages Sn deposited on Cu(111)leads to the formation of a two-dimensional (2D) alloy phase with a p(root 3 x root 3)-R 30 degrees structure which is stable up to temperatures of 1200K. For deposition of Sn on Cu(100), a coverage of one-quarter of a monolayer results in the formation of a stable 2D alloy phase with a p(2 x 2) structure. These results are in agreement with ion-scattering experiments. It is found that on both Cu(100) and Cu(111) surfaces, the resulting alloy phases are rippled with the Sn atoms displaced outward from the surfaces. C1 Univ Texas, Dept Phys, El Paso, TX 79968 USA. Univ Texas, Mat Res Inst, El Paso, TX 79968 USA. Sandia Natl Labs, Mat Reliabil Dept, Livermore, CA 94551 USA. RP Aguilar, JF (reprint author), Univ Texas, Dept Phys, El Paso, TX 79968 USA. NR 16 TC 14 Z9 14 U1 2 U2 14 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD MAY PY 2000 VL 8 IS 3 BP 335 EP 344 DI 10.1088/0965-0393/8/3/313 PG 10 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 323LU UT WOS:000087567500014 ER PT J AU Richards, KL Anders, KR Nogales, E Schwartz, K Downing, KH Botstein, D AF Richards, KL Anders, KR Nogales, E Schwartz, K Downing, KH Botstein, D TI Structure-function relationships in yeast tubulins SO MOLECULAR BIOLOGY OF THE CELL LA English DT Article ID SYSTEMATIC MUTATIONAL ANALYSIS; SACCHAROMYCES-CEREVISIAE; BETA-TUBULIN; ALPHA-TUBULIN; PHENOTYPIC CONSEQUENCES; MITOTIC SPINDLE; ENCODING GENE; PROTEIN; MICROTUBULE; ACTIN AB A comprehensive set of clustered charged-to-alanine mutations was generated that systematically alter TUB1, the major alpha-tubulin gene of Saccharomyces cerevisiae. A variety of phenotypes were observed, including supersensitivity and resistance to the microtubule-destabilizing drug benomyl, lethality, and cold- and temperature-sensitive lethality. Many of the most benomyl-sensitive tub1 alleles were synthetically lethal in combination with tub3 Delta, supporting the idea that benomyl supersensitivity is a rough measure of microtubule instability and/or insufficiency in the amount of cr-tubulin. The systematic tub1 mutations were placed, along with the comparable set of tub2 mutations previously described, onto a model of the yeast alpha-beta-tubulin dimer based on the three-dimensional structure of bovine tubulin. The modeling revealed a potential site for binding of benomyl in the core of beta-tubulin. Residues whose mutation causes cold sensitivity were concentrated at the lateral and longitudinal interfaces between adjacent subunits. Residues that affect binding of the microtubule-binding protein Bim1p form a large patch across the exterior-facing surface of alpha-tubulin in the model. Finally, the positions of the mutations suggest that proximity to the alpha-beta interface may account for the finding of synthetic lethality of five viable tub1 alleles with the benomyl-resistant but otherwise entirely viable tub2-201 allele. C1 Stanford Univ, Sch Med, Dept Genet, Stanford, CA 94305 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Stanford Univ, Sch Med, Dept Genet, Stanford, CA 94305 USA. EM botstein@genome.stanford.edu FU NIGMS NIH HHS [GM46406, R01 GM046406, R37 GM046406] NR 59 TC 89 Z9 91 U1 3 U2 4 PU AMER SOC CELL BIOLOGY PI BETHESDA PA 8120 WOODMONT AVE, STE 750, BETHESDA, MD 20814-2755 USA SN 1059-1524 EI 1939-4586 J9 MOL BIOL CELL JI Mol. Biol. Cell PD MAY PY 2000 VL 11 IS 5 BP 1887 EP 1903 PG 17 WC Cell Biology SC Cell Biology GA 314HE UT WOS:000087049700030 PM 10793159 ER PT J AU Kim, CH Kao, CC Tinoco, I AF Kim, CH Kao, CC Tinoco, I TI RNA motifs that determine specificity between a viral replicase and its promoter SO NATURE STRUCTURAL BIOLOGY LA English DT Article ID BROME MOSAIC-VIRUS; IRREGULAR NUCLEIC-ACIDS; NMR-SPECTROSCOPY; SECONDARY STRUCTURE; POLYMERASE; SEQUENCE; INITIATION; STABILITY; OLIGONUCLEOTIDES; AMINOACYLATION AB The 3' end of brome mosaic virus RNA contains a tRNA-like sequence that directs its RNA synthesis, A stem loop structure in this sequence, stem loop C (SLC), was investigated using NMR, and correlated with its ability to direct RNA synthesis by its replicase. SLC consists of two discrete domains, a flexible stem with an internal loop and a rigid stem containing a 5'-AUA-3' triloop. Efficient RNA synthesis requires the sequence on only one side of the flexible stem and a specific compact conformation of the triloop. A high resolution structure of the triloop places the 5' adenine out in solution, and the 3' adenine within the triloop. held tightly through stacking and unusual hydrogen bonds. This high resolution structure of an RNA promoter from a (+)-strand RNA virus provides new insights into how the RNA-dependent RNA polymerase binds to the RNA to initiate synthesis. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Indiana Univ, Dept Biol, Bloomington, IN 47405 USA. RP Tinoco, I (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 45 TC 58 Z9 60 U1 1 U2 4 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1072-8368 J9 NAT STRUCT BIOL JI Nat. Struct. Biol. PD MAY PY 2000 VL 7 IS 5 BP 415 EP 423 PG 9 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 311WH UT WOS:000086908800019 PM 10802741 ER PT J AU Hwang, DQ McLean, HS Baker, KL Evans, RW Horton, RD Terry, SD Howard, S Schmidt, GL AF Hwang, DQ McLean, HS Baker, KL Evans, RW Horton, RD Terry, SD Howard, S Schmidt, GL TI Interaction of a spheromak-like compact toroid with a high beta spherical tokamak plasma SO NUCLEAR FUSION LA English DT Article ID OPERATION AB Recent experiments using accelerated spheromak-like compact toroids (SCTs) to fuel tokamak plasmas have quantified the penetration mechanism in the low beta regime; i.e. external magnetic field pressure dominates plasma thermal pressure. However, fusion reactor designs require high beta plasma and, more importantly, the proper plasma pressure profile. Here, the effect of the plasma pressure profile on SCT penetration, specifically, the effect of diamagnetism, is addressed. It is estimated that magnetic field pressure dominates penetration even up to 50% local beta. The combination of the diamagnetic effect on the toroidal magnetic field and the strong poloidal field at the outer major radius of a spherical tokamak will result in a diamagnetic well in the total magnetic field. Therefore, the spherical tokamak is a good candidate to test the potential trapping of an SCT in a high beta diamagnetic well. The diamagnetic effects of a high beta spherical tokamak discharge (low aspect ratio) are computed. To test the penetration of an SCT into such a diamagnetic well, experiments have been conducted of SCT injection into a vacuum field structure a which simulates the diamagnetic field effect of a high beta tokamak. The diamagnetic field gradient length is substantially shorter than that of the toroidal field of the tokamak, and the results show that it can still improve the penetration of the SCT. Finally, analytic results have been used to estimate the effect of plasma pressure on penetration and the effect of plasma pressure was found to be small in comparison with the magnetic field pressure. The penetration condition for a vacuum field only is reported. To study the diamagnetic effect in a high beta plasma, additional experiments need to be carried out on a high beta spherical tokamak. C1 Univ Calif Davis, Dept Appl Sci, Livermore, CA 95616 USA. Bennington Coll, Bennington, VT USA. Princeton Univ, Plasma Phys Lab, Princeton, NJ USA. RP Hwang, DQ (reprint author), Univ Calif Davis, Dept Appl Sci, Livermore, CA 95616 USA. NR 14 TC 8 Z9 8 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 MAY PY 2000 VL 40 IS 5 BP 897 EP 905 DI 10.1088/0029-5515/40/5/302 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 313RW UT WOS:000087013900001 ER PT J AU Hoang, GT Monier-Garbet, P Aniel, T Bourdelle, C Budny, RV Clairet, F Eriksson, LG Garbet, X Grisolia, C Platz, P Vallet, JC AF Hoang, GT Monier-Garbet, P Aniel, T Bourdelle, C Budny, RV Clairet, F Eriksson, LG Garbet, X Grisolia, C Platz, P Vallet, JC TI An H minority heating regime in Tore Supra showing improved L mode confinement SO NUCLEAR FUSION LA English DT Article ID TOROIDAL ROTATION; HEATED PLASMAS; HIGH-DENSITY; SIMULATIONS; DISCHARGES; PROFILES; TOKAMAKS; JET AB Tore Supra experiments are at present devoted to the study of high density regimes with radiofrequency heating. Recently, an improved L mode confinement regime has been observed in plasmas heated by ion cyclotron hydrogen minority heating, at relatively high densities up to 80% of the Greenwald limit. The quality of energy confinement is as good as that of ELMy H mode. The main physical mechanism of this regime has not been clearly identified. However, some features very similar to those of previous improved confinement modes using neutral beam heating in other tokamaks have been observed. C1 CEA Cadarache, EURATOM Assoc, Dept Rech Fus Controlee, St Paul Durance, France. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Hoang, GT (reprint author), CEA Cadarache, EURATOM Assoc, Dept Rech Fus Controlee, St Paul Durance, France. RI ANIEL, Thierry/G-8734-2011 OI ANIEL, Thierry/0000-0002-2598-9551 NR 23 TC 38 Z9 38 U1 1 U2 9 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 MAY PY 2000 VL 40 IS 5 BP 913 EP 921 DI 10.1088/0029-5515/40/5/304 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 313RW UT WOS:000087013900003 ER PT J AU Jardin, SC Schmidt, GL Fredrickson, ED Hill, KW Hyun, J Merrill, BJ Sayer, R AF Jardin, SC Schmidt, GL Fredrickson, ED Hill, KW Hyun, J Merrill, BJ Sayer, R TI A fast shutdown technique for large tokamaks SO NUCLEAR FUSION LA English DT Article ID RUNAWAY ELECTRONS; PELLET INJECTION; PLASMA; TRANSPORT; AVALANCHE; ITER AB A practical method is proposed for the fast shutdown of a large ignited tokamak. The method consists of injecting a rapid series of 30-45 (6 mm) deuterium pellets doped with a small (0.0005%) concentration of krypton impurity, and simultaneously ramping the plasma current and shaping fields down over a period of several seconds using the poloidal field system. Detailed modelling with the Tokamak Simulation Code using a newly developed pellet mass deposition model shows that this method should terminate the discharge in a controlled and stable way without producing significant numbers of runaway electrons. A partial prototyping of this technique was accomplished in TFTR. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Jardin, SC (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Jardin, Stephen/E-9392-2010 NR 21 TC 24 Z9 24 U1 0 U2 2 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 2000 VL 40 IS 5 BP 923 EP 933 DI 10.1088/0029-5515/40/5/305 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 313RW UT WOS:000087013900004 ER PT J AU Baker, DR Wade, MR Petty, CC Rosenbluth, MN Luce, TC deGrassie, JS Rice, BW Groebner, RJ Greenfield, CM Doyle, EJ Rettig, CL Rhodes, TL Mahdavi, MA AF Baker, DR Wade, MR Petty, CC Rosenbluth, MN Luce, TC deGrassie, JS Rice, BW Groebner, RJ Greenfield, CM Doyle, EJ Rettig, CL Rhodes, TL Mahdavi, MA TI Particle transport phenomena in the DIII-D tokamak SO NUCLEAR FUSION LA English DT Article ID DENSITY PROFILE CONSISTENCY; GRADIENT-DRIVEN TURBULENCE; PULSE-PROPAGATION; HELIUM TRANSPORT; PINCH; COEFFICIENTS; EQUILIBRIUM; OPERATION; INVARIANT; PLASMAS AB Many theoretical models show a direct connection between energy transport and particle transport. For a complete understanding of transport processes both energy and particle transport must be understood. A discussion is presented of how energy and particle transport should be related in terms of the relative importance of the diagonal and off-diagonal terms in the equation for the fluxes. A model for particle transport is discussed and it is shown that this model can describe measured density profiles in the DIII-D tokamak under a wide range of DIII-D parameters. This model is obtained from a Lagrangian formulation of the kinetic equation and utilizes the assumption that transport takes place while approximately conserving the first and second adiabatic invariants. The measured results utilize the improved diagnostic capability of DIII-D with an improved capability of measuring current density profiles and particle density profiles. This model is then extended to include energy transport. It is experimentally observed that the particle diffusivity and the thermal diffusivity do not differ greatly and have roughly the same radial dependence. This is discussed and compared with the model. A brief discussion of the effect of internal transport barriers is included. C1 Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Calif Los Angeles, Los Angeles, CA USA. RP Baker, DR (reprint author), Gen Atom Co, San Diego, CA 92186 USA. NR 40 TC 45 Z9 45 U1 0 U2 1 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 MAY PY 2000 VL 40 IS 5 BP 1003 EP 1016 DI 10.1088/0029-5515/40/5/301 PG 14 WC Physics, Fluids & Plasmas SC Physics GA 313RW UT WOS:000087013900011 ER PT J AU Dejus, RJ Shevchenko, OA Vinokurov, NA AF Dejus, RJ Shevchenko, OA Vinokurov, NA TI A linear integral-equation-based computer code for self-amplified spontaneous emission calculations of free-electron lasers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE free-electron laser; simulation ID FEL AB The linear integral-equation-based computer code "Roger Oleg Nikolai" (RON), which was recently developed at Argonne National Laboratory, was used to calculate the self-amplified spontaneous emission (SASE) performance of the free-electron laser (FEL) being built at Argonne. Signal growth calculations under different conditions were used to estimate tolerances of actual design parameters and to estimate optimal length of the break sections between undulator segments. Explicit calculation of the radiation field was added recently. The measured magnetic fields of five undulators were used to calculate the gain for the Argonne FEL. The result indicates that the real undulators for the Argonne FEL (the effect of magnetic field errors alone) will not significantly degrade the FEL performance. The capability to calculate the small-signal gain for an FEL-oscillator is also demonstrated. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. RP Dejus, RJ (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 19 EP 23 DI 10.1016/S0168-9002(00)00106-6 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900006 ER PT J AU Kim, KJ AF Kim, KJ TI Kick and phase errors in spontaneous and amplified radiation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE free electron lasers; magnet errors ID FREE-ELECTRON-LASER; PERFORMANCE; UNDULATOR AB Two types of magnet errors are considered - the random phase error (RPE), in which the phase errors are evenly distributed along the magnet, and the random kick error (RKE) in which the errors in the derivative of the phase are evenly distributed. We compute the reduction in performance of both spontaneous radiation and high-gain free-electron lasers for both types of errors within the framework of 1-D free-electron laser theory, (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Adv Photon Source, Accelerator Syst Div, Argonne, IL 60439 USA. RP Kim, KJ (reprint author), Argonne Natl Lab, Adv Photon Source, Accelerator Syst Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 TC 1 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 24 EP 27 DI 10.1016/S0168-9002(00)00107-8 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900007 ER PT J AU Freund, HP Biedron, SG Milton, SV AF Freund, HP Biedron, SG Milton, SV TI Nonlinear harmonic generation and proposed experimental verification in SASE FELs SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY ID ADVANCED PHOTON SOURCE; FREE-ELECTRON-LASER; GAIN; RADIATION AB Recently, a 3D, polychromatic, nonlinear simulation code was developed to study the growth of nonlinear harmonics in self-amplified spontaneous emission (SASE) free-electron lasers (FELs). The simulation was applied to the parameters for each stage of the Advanced Photon Source (APS) SASE FEL, intended for operation in the visible, UV, and short UV wavelength regimes, respectively, to study the presence of nonlinear harmonic generation. Significant nonlinear harmonic growth is seen. Here, a discussion of the code development, the APS SASE FEL, the simulations and results, and, finally, the proposed experimental procedure for verification of such nonlinear harmonic generation at the APS SASE FEL will be given. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Sci Applicat Int Corp, Mclean, VA 22102 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Freund, HP (reprint author), Sci Applicat Int Corp, 1710 Goodridge Dr, Mclean, VA 22102 USA. EM freund@mmace.nrl.navy.mil NR 24 TC 33 Z9 34 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 53 EP 58 DI 10.1016/S0168-9002(00)00113-3 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900013 ER PT J AU Xie, M AF Xie, M TI Exact and variational solutions of 3D eigenmodes in high gain FELs SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE 3D; high gain FEL theory; optical guiding; SASE ID FREE-ELECTRON-LASER; REGIME AB Exact solution and variational approximation of eigenmodes in high gain FELs are presented. These eigenmodes specify transverse profiles and exponential growth rates of the laser field before saturation. They are self-consistent solutions of coupled Maxwell-Vlasov equations describing FEL interaction taking into account the effects due to energy spread, emittance and betatron oscillations of the electron beam, as well as diffraction and optical guiding of the laser field. A new formalism of scaling is introduced and based on which solutions in various limiting cases are discussed. In addition, a fitting formula is obtained from interpolating the variational solution for quick calculation of exponential growth rate of the fundamental mode. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Xie, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 71-259, Berkeley, CA 94720 USA. NR 17 TC 89 Z9 90 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 59 EP 66 DI 10.1016/S0168-9002(00)00114-5 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900014 ER PT J AU Xie, M AF Xie, M TI Transverse coherence of self-amplified spontaneous emission SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE transverse coherence; SASE; 3D; high-gain FEL theory ID FREE-ELECTRON LASERS; HIGH-GAIN; MODES; FEL AB Transverse coherence of Self-Amplified Spontaneous Emission (SASE) in high-gain FELs is investigated through a three-dimensional eigenmode analysis. It is the first time such an analysis could be carried out to account for the effects of emittance and betatron focusing. In addition to the variational solution (Xie, Nucl. Instr. and Meth. A 445 (2000) 59, these proceedings) found for the fundamental mode, E-00, similar solutions are derived here for two higher order eigenmodes, E-10 and E-01. Based on the growth rates of these three modes, a universal criteria on transverse coherence of SASE is proposed. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Xie, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 71-259, Berkeley, CA 94720 USA. NR 12 TC 13 Z9 13 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 67 EP 71 DI 10.1016/S0168-9002(00)00115-7 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900015 ER PT J AU Biedron, SG Freund, HP Yu, LH AF Biedron, SG Freund, HP Yu, LH TI Parameter analysis for a high-gain harmonic generation FEL using a recently developed 3D polychromatic code SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY ID FREE-ELECTRON LASERS; SIMULATION; RADIATION AB One possible design for a fourth-generation light source is the high-gain harmonic generation (HGHG) free-electron laser (FEL). Here, a coherent seed with a wavelength at a subharmonic of the desired output radiation interacts with the electron beam in an energy-modulating section. This energy modulation is then converted into spatial bunching while traversing a dispersive section (a three-dipole chicane). The final step is passage through an undulator tuned to the desired higher harmonic output wavelength. The coherent seed serves to suppress noise and can be at a much lower subharmonic of the output radiation. Recently, a 3D code that includes multiple frequencies, multiple undulators (both in quantity and/or type), quadrupole magnets, and dipole magnets was developed to easily simulate HGHG. Here, a brief review of the HGHG theory, the code development, the Accelerator Test Facility's (ATF) HGHG FEL experimental parameters, and the parameter analysis from simulations of this specific experiment will be discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Biedron, SG (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NR 9 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 95 EP 100 DI 10.1016/S0168-9002(00)00120-0 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900020 ER PT J AU Huang, ZR Kim, KJ AF Huang, ZR Kim, KJ TI Effects of bunch density gradient in high-gain free-electron lasers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE bunched beam; coherent spontaneous emission; high-gain free-electron laser; self-amplified spontaneous emission ID AMPLIFIED-SPONTANEOUS-EMISSION; NOISE AB We investigate effects of the bunch density gradient in self-amplified spontaneous emission, including the role of coherent spontaneous emission (CSE) in the evolution of the free-electron laser process. In the exponential gain regime, we solve the coupled Maxwell-Vlasov equations and extend the linear theory to a bunched beam with energy spread. A time-dependent, nonlinear simulation algorithm is used to study the CSE effect and the nonlinear evolution of the radiation pulse. Published by Elsevier Science B.V. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Huang, ZR (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 105 EP 109 DI 10.1016/S0168-9002(00)00122-4 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900022 ER PT J AU Biedron, SG Chae, YC Dejus, RJ Faatz, B Freund, HP Milton, SV Nuhn, HD Reiche, S AF Biedron, SG Chae, YC Dejus, RJ Faatz, B Freund, HP Milton, SV Nuhn, HD Reiche, S TI Multi-dimensional free-electron laser simulation codes: a comparison study SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY ID FEL SIMULATION; GAIN AB A self-amplified spontaneous emission (SASE) free-electron laser(FEL) is under construction at the Advanced Photon Source (APS). Five FEL simulation codes were used in the design phase: GENESIS, GINGER, MEDUSA, RON, and TDA3D. Initial comparisons between each of these independent formulations show good agreement for the parameters of the APS SASE FEL. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. DESY, D-22603 Hamburg, Germany. Sci Applicat Int Corp, Mclean, VA 22101 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Biedron, SG (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 16 Z9 16 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 110 EP 115 DI 10.1016/S0168-9002(00)00124-8 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900023 ER PT J AU Nuhn, HD AF Nuhn, HD TI Technological challenges to X-ray FELs SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY ID AMPLIFIED SPONTANEOUS-EMISSION; FREE-ELECTRON LASER; GENERATION; INJECTOR; DESIGN; GAIN AB There is strong interest in the development of X-ray Free Electron Lasers (X-ray FELs). The interest is driven by the scientific opportunities provided by intense, coherent X-rays. An X-ray FEL has all the characteristics of a fourth-generation source: brightness several orders of magnitude greater than presently achieved in third-generation sources, full transverse coherence, and sub-picosecond long pulses. The SLAG and DESY laboratories have presented detailed design studies for X-ray FEL user-facilities around the 0.1 nm wavelength regime (LCLS at SLAG, TESLA X-ray FEL at DESY). Both laboratories are engaged in proof-of-principle experiments at longer wavelengths (TTF FEL Phase I at 71 nm, VISA at 600-800 nm) with results expected in 1999. The technologies needed to achieve the proposed performances are those of bright electron sources, of acceleration systems capable of preserving the brightness of the source, and of undulators capable of meeting the magnetic and mechanical tolerances that are required for operation in the SASE mode. This paper discusses the technological challenges presented by the X-ray FEL projects. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Nuhn, HD (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, POB 4249, Stanford, CA 94309 USA. NR 23 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 149 EP 154 DI 10.1016/S0168-9002(00)00053-X PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900030 ER PT J AU Tremaine, A Frigola, P Murokh, A Musumeci, P Pellegrini, C Rosenzweig, J Babzien, M Ben-Zvi, I Johnson, E Malone, R Rakowsky, G Skaritka, J Wang, XJ Yu, LH Van Bibber, KA Hill, JM Le Sage, GP Carr, R Cornacchia, M Nuhn, HD Ruland, R Nguyen, DC AF Tremaine, A Frigola, P Murokh, A Musumeci, P Pellegrini, C Rosenzweig, J Babzien, M Ben-Zvi, I Johnson, E Malone, R Rakowsky, G Skaritka, J Wang, XJ Yu, LH Van Bibber, KA Hill, JM Le Sage, GP Carr, R Cornacchia, M Nuhn, HD Ruland, R Nguyen, DC TI Status and initial commissioning of a high gain 800 nm SASE FEL SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE SASE; FEL; saturation; strong focussing; undulator AB We describe the status and initial commissioning of the Visible to Infrared SASE Amplifier (VISA) experiment. VISA uses a strong focusing 4 m undulator, the Brookhaven National Laboratory ATF linac with an energy of 72 McV, and a photoinjector electron source. The VISA fundamental radiation wavelength is near 800 nm and the power expected at saturation is near 60 MW. Power, angular and spectral measurements are planned for the VISA radiation and these results will be analyzed and compared with SASE FEL theory and computer simulation. In addition, the induced electron beam micro-bunching will be measured using coherent transition radiation. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. LLNL, Livermore, CA 94551 USA. SLAC, Berkeley, CA 94720 USA. LANL, Los Alamos, NM 87545 USA. RP Tremaine, A (reprint author), Brookhaven Natl Lab, Bldg 725,Brookhave Ave, Upton, NY 11973 USA. NR 12 TC 2 Z9 3 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 MAY 1 PY 2000 VL 445 IS 1-3 BP 160 EP 163 DI 10.1016/S0168-9002(00)00055-3 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900032 ER PT J AU Neil, GR Benson, S Biallas, G Bohn, CL Douglas, D Dylla, HF Evans, R Fugitt, J Gubeli, J Hill, R Jordan, K Krafft, G Li, R Merminga, L Oepts, D Piot, P Preble, J Shinn, M Siggins, T Walker, R Yunn, B AF Neil, GR Benson, S Biallas, G Bohn, CL Douglas, D Dylla, HF Evans, R Fugitt, J Gubeli, J Hill, R Jordan, K Krafft, G Li, R Merminga, L Oepts, D Piot, P Preble, J Shinn, M Siggins, T Walker, R Yunn, B TI First operation of an FEL in same-cell energy recovery mode SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE lasing; free-electron laser; recirculation AB The driver for Jefferson Lab's kW-level infrared free-electron laser (FEL) is a supcrsonducting, recirculating accelerator that recovers 75% of the electron-beam power and converts it to radio frequency power, As reported in FEL'98, the accelerator operated "straight-ahead" to deliver 38 MeV. 1.1 mA cw current for lasing at wavelengths in the vicinity of 5 mu m. The waste beam was sent directly to a dump, bypassing the recirculation loop. Stable operation at up to 311 W cw was achieved in this mode. The machine has now recirculated cw average current up to 4.7 mA, and has lased cw with energy recovery up to 1720 W output at 3.1 mu m. This is the first FEL to ever operate in the ''same-cell" energy recovery mode. Energy recovery offers several advantages (reduced RF power and dramatically reduced radio-nuclide production at the dump) and several challenges (potential for instabilities and difficult beam transport due to large energy spreads). Solutions to these challenges will be described. We have observed heating effects in the mirrors which will be described. We will also report on the additional performance measurements of the FEL that have been performed and connect those measurements to standard models. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Thomas Jefferson Natl Accelerator Fac, Newport News, VA 23606 USA. RP Neil, GR (reprint author), Thomas Jefferson Natl Accelerator Fac, MS 6A,12000 Jefferson Ave, Newport News, VA 23606 USA. OI EVANS, ROBIN/0000-0002-7988-3189 NR 11 TC 20 Z9 23 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 MAY 1 PY 2000 VL 445 IS 1-3 BP 192 EP 196 DI 10.1016/S0168-9002(00)00064-4 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900039 ER PT J AU Yu, LH Babzien, M Ben-Zvi, I DiMauro, LF Doyuran, A Graves, W Johnson, E Krinsky, S Malone, R Pogorelsky, I Skaritka, J Rakowsky, G Solomon, L Wang, XJ Woodle, M Yakimenko, V Biedron, SG Galayda, JN Gluskin, E Jagger, J Sajaev, V Vassserman, I AF Yu, LH Babzien, M Ben-Zvi, I DiMauro, LF Doyuran, A Graves, W Johnson, E Krinsky, S Malone, R Pogorelsky, I Skaritka, J Rakowsky, G Solomon, L Wang, XJ Woodle, M Yakimenko, V Biedron, SG Galayda, JN Gluskin, E Jagger, J Sajaev, V Vassserman, I TI First lasing of a high-gain harmonic generation free- electron laser experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY ID RADIATION AB We report on the first lasing of a high-gain harmonic generation (HGHG) free-electron laser (FEL). The experiment was conducted at the Accelerator Test Facility (ATF) at Brookhaven National Laboratory (BNL). This is a BNL experiment in collaboration with the Advanced Photon Source (APS) at Argonne National Laboratory. A preliminary measurement gives a high-gain harmonic generation (HGHG) pulse energy that is 2 x 10(7) times larger than the spontaneous radiation. In a purely self-amplified spontaneous emission (SASE) mode of operation, the signal was measured as 10 times larger than the spontaneous radiation in the same distance ( similar to 2 m) through the same wiggler. This means the HGHG signal is 2 x 10(6) times larger than the SASE signal. To obtain the same saturated output power by the SASE process, the radiator would have to be 3 times longer (6 m). Published by Elsevier Science B.V. C1 Brookhaven Natl Lab, ATF, Upton, NY 11973 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Yu, LH (reprint author), Brookhaven Natl Lab, ATF, NSLS Bldg,725 C,Box 5000, Upton, NY 11973 USA. NR 8 TC 30 Z9 30 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 301 EP 306 DI 10.1016/S0168-9002(00)00131-5 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900059 ER PT J AU Donohue, JT Gardelle, J Lefevre, T Rullier, JL Vermare, C Lidia, SM Meurdesoif, Y AF Donohue, JT Gardelle, J Lefevre, T Rullier, JL Vermare, C Lidia, SM Meurdesoif, Y TI Power generation in a resonant cavity using a beam bunched at 35 GHz by a free electron laser SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE free electron laser; resonant cavity; two-beam accelerator AB An intense beam of relativistic electrons (800 A, 6.7 MeV) has been bunched at 35 GHz by a free-electron laser, in which output power levels exceeding 100 MW were obtained. The beam was then extracted and transported through a resonant cavity, that was excited by its passage. Microwave power levels of 10 MW were extracted from the cavity, in reasonable agreement with a simple formula which relates power output to known properties of the both beam and cavity. (C) 2000 Elsevier Science B.V. All rights reserved. C1 CEN Bordeaux Gradignan, F-33175 Gradignan, France. Ctr Etud Sci & Tech Aquitaine, F-33114 Le Barp, France. EO Lawrence Berkeley Natl Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. Univ Bordeaux 1, Ctr Phys Theoret & Modelisat, F-33405 Talence, France. RP Donohue, JT (reprint author), CEN Bordeaux Gradignan, BP 120, F-33175 Gradignan, France. NR 12 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 307 EP 312 DI 10.1016/S0168-9002(00)00132-7 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900060 ER PT J AU Kim, KJ AF Kim, KJ TI Circular polarization with crossed-planar undulators in high-gain FELs SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE free electron lasers; circular polarization ID AMPLIFIED SPONTANEOUS EMISSION; FREE-ELECTRON LASER AB We propose a crossed undulator configuration for a high-gain free-electron laser to allow versatile polarization control. This configuration consists of a long (saturation length) planar undulator, a dispersive section, and a short (a few gain lengths) planar undulator oriented perpendicular to the first one. In the first undulator, a radiation component linearly polarized in the x-direction is amplified to saturation. In the second undulator, the x-polarized component propagates freely, while a new component, polarized in the p-direction, is generated and reaches saturation in a few gain lengths. By adjusting the strength of the dispersive section, the relative phase of two radiation components can be adjusted to obtain a suitable polarization for the total radiation field, including the circular polarization. The operating principle of the high-gain crossed undulator, which is quite different from that of the crossed undulator for spontaneous radiation, is illustrated in terms of 1-D FEL theory. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Adv Photon Source, Accelerator Syst Div, Argonne, IL 60439 USA. RP Kim, KJ (reprint author), Argonne Natl Lab, Adv Photon Source, Accelerator Syst Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 27 Z9 29 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 329 EP 332 DI 10.1016/S0168-9002(00)00137-6 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900065 ER PT J AU Lumpkin, AH Yang, BX Berg, WJ Lewellen, JW Sereno, NS Happek, U AF Lumpkin, AH Yang, BX Berg, WJ Lewellen, JW Sereno, NS Happek, U TI Electron beam bunch length characterizations using incoherent and coherent transition radiation on the APS SASE FEL project SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY AB The Advanced Photon Source (APS) injector linac has been reconfigured with a low-emittance RF thermionic gull and a photocathode (PC) RF gun to support self-amplified spontaneous emission (SASE) free-electron laser (FEL) experiments. One of the most critical parameters for optimizing SASE performance (gain length) is the electron beam peak current, which requires a charge measurement and a bunch length measurement capability. We report here initial measurements of the latter using both incoherent optical transition radiation (OTR) and coherent transition radiation (CTR). A visible light Hamamatsu C5680 synchroscan streak camera was used to measure the thermionic RF gun beam's bunch length (sigma similar to 2-3 ps) via OTR generated by the beam at 220 MeV and 200 mA macropulse average current. In addition, a CTR monitor (Michelson Interferometer) based on a Golay cell as the far-infrared (FIR) detector has been installed at the 40-MeV station in the beamline. Initial observations of CTR signal strength variation with gull cc-magnet current and interferograms have been obtained. Progress in characterizing the beam at these locations and a comparison to other bunch length determinations will be presented. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ Georgia, Dept Phys, Athens, GA 30602 USA. RP Lumpkin, AH (reprint author), Argonne Natl Lab, Adv Photon Source, Bldg 40,9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 5 Z9 5 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 MAY 1 PY 2000 VL 445 IS 1-3 BP 356 EP 361 DI 10.1016/S0168-9002(00)00143-1 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900071 ER PT J AU Andersson, A Eriksson, M Werin, S Biedron, S Freund, H AF Andersson, A Eriksson, M Werin, S Biedron, S Freund, H TI An RF-gun-driven recirculated linac as injector and FEL driver SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE RF gun; thermionic; linac; FEL; injector AB A new pre-injector for the MAX-Laboratory is under design and construction. A thermionic RF gun, designed to operate at medium currents with low back bombardment power, is under construction. The gun will, via a magnetic compressor and energy filter, feed a recirculated linac consisting of two SLED-equipped structures giving 125 MeV each. The first will be delivered in 1999. The system is aimed as a pre-injector for the existing storage rings at MAX-Lab, but will also open up possibilities for a SASE FEL in the UV reaching above 100 MW below 100 nm. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Lund, Max Lab, S-22100 Lund, Sweden. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. RP Werin, S (reprint author), Univ Lund, Max Lab, Box 118, S-22100 Lund, Sweden. NR 8 TC 5 Z9 5 U1 1 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 MAY 1 PY 2000 VL 445 IS 1-3 BP 413 EP 421 DI 10.1016/S0168-9002(00)00094-2 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900082 ER PT J AU Hahn, U den Hartog, PK Pfluger, J Ruter, M Schmidt, G Trakhtenberg, EM AF Hahn, U den Hartog, PK Pfluger, J Ruter, M Schmidt, G Trakhtenberg, EM TI Design and performance of the vacuum chambers for the undulator of the VUVFEL at the TESLA test facility at DESY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 21st Annual International Conference on Free Electron Laser CY AUG 23-26, 1999 CL DESY, HAMBURG, GERMANY SP DEDSY, ACCEL Instruments GmbH, Deutsch Forsch Gemeinschaft, USN, Off Res, Lufthansa AG, Hansestadt Hamburg, Elsevier Sci BV, Vaccuumschmelze GmbH, Danfysik AS, Puls Plasmatechn GmbH HO DESY DE vacuum chamber; undulator; beam position monitor; corrector coils ID FEL AB Three vacuum chambers for the VUV SASE FEL undulator sections at the TESLA Test Facility (TTF) were designed, built, tested and installed. Each chamber is 4.5 m long and of 11.5 mm thick. The inner diameter of the beam pipe is 9.5 mm. The rectangular chamber profile with a width of 128 mm is used to integrate beam position monitors and steerers. This is needed to provide a good overlap between the electron and the photon beam over the entire undulator length. The chambers are built in an aluminum extrusion technology developed for the insertion device vacuum chambers of the Advanced Photon Source. After manufacturing, special processing was performed to reach low outgassing rates (<1x10(-11)mbar.1/s.cm(2)) and particle-free chambers. Mounting of the chambers at TTF were performed under clean room conditions better class 100. (C) 2000 Elsevier Science B.V. All rights reserved. C1 DESY, HASYLAB, D-22603 Hamburg, Germany. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Hahn, U (reprint author), DESY, HASYLAB, Notkestr 85, D-22603 Hamburg, Germany. NR 11 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 2000 VL 445 IS 1-3 BP 442 EP 447 DI 10.1016/S0168-9002(00)00099-1 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 319AY UT WOS:000087317900087 ER PT J AU Selim, FA Hunt, AW Howell, R Lynn, KG Golovchenko, JA AF Selim, FA Hunt, AW Howell, R Lynn, KG Golovchenko, JA TI Multiple scattering measurements of energetic positrons in a thin gold polycrystal SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE positron scattering; multiple scattering; channeling; image plate detector ID IMAGING PLATE; ELECTRON AB As a step towards developing fast positrons as a probe to measure electron density and spin magnetic density in crystals, an experiment has been performed to measure the multiple scattering distribution of MeV positrons penetrating through thin polycrystalline films in both random and channeling directions. Image plate detectors were used to determine the angular distribution of emergent positrons. Image plate sensitivity was measured for high-energy positrons and for the background radiation encountered in our experiment. The image plates showed good sensitivity and good linearity for MeV positrons. The multiple scattering results are compared with the theory for random direction and show disagreement due to crystal effects and quantum mechanical considerations. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Harvard Univ, Dept Phys, Cambridge, MA 02138 USA. Washington State Univ, Dept Phys, Pullman, WA 99164 USA. Rowland Inst Sci Inc, Cambridge, MA 02142 USA. RP Selim, FA (reprint author), Univ Alexandria, Fac Engn, Dept Engn Phys, Alexandria 21544, Egypt. EM selim@huhepu.harvard.edu RI Selim, Farida/N-8077-2016 NR 24 TC 3 Z9 3 U1 1 U2 3 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 MAY PY 2000 VL 168 IS 1 BP 1 EP 10 DI 10.1016/S0168-583X(99)00718-1 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 317RU UT WOS:000087241400001 ER PT J AU Evans, PJ Vilaithong, T Yu, LD Monteiro, OR Yu, KM Brown, IG AF Evans, PJ Vilaithong, T Yu, LD Monteiro, OR Yu, KM Brown, IG TI Tribological effects of oxygen ion implantation into stainless steel SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE oxygen ion implantation; stainless steel; wear; friction; surface modification ID NITROGEN; VACUUM; GAS; FRICTION; CARBON; WEAR AB The formation of sub-surface oxide layers by hybrid metal-gas co-implantation into steel and other metals can improve their tribological properties. In this report, we compare the wear and friction performance of previously studied Al+O hybrid implants with that produced by single species oxygen ion (O+) implantation under similar conditions. The substrates were AISI 304L stainless steel discs polished to a final mirror finish using 1 mu m diamond paste, and the ion implantation was done using a conventional swept-beam technique at ion energies of 70 or 140 keV and doses of up to 1 x 10(17) cm(-2). The wear and friction behaviour of the implanted and unimplanted material was measured with a pin-on-disc tribometer. Here we describe the experimental procedure and results, and discuss the improvement relative to that achieved with surface layers modified by metal-gas co-implantation. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Australian Nucl Sci & Technol Org, Div Phys, Menai, NSW 2234, Australia. Chiang Mai Univ, Dept Phys, Chiang Mai 50200, Thailand. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Evans, PJ (reprint author), Australian Nucl Sci & Technol Org, Div Phys, Private Mail Bag 1, Menai, NSW 2234, Australia. RI Yu, Kin Man/J-1399-2012 OI Yu, Kin Man/0000-0003-1350-9642 NR 16 TC 6 Z9 6 U1 0 U2 3 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 MAY PY 2000 VL 168 IS 1 BP 53 EP 58 DI 10.1016/S0168-583X(99)00764-8 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 317RU UT WOS:000087241400007 ER PT J AU Eaton, SL Beard, CA Daemen, LL Wilson, WB Adams, ML AF Eaton, SL Beard, CA Daemen, LL Wilson, WB Adams, ML TI Calculational analysis of structural activation induced by 20-100 Mev proton beam loss in high-power linear accelerators SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE beam loss; activation; linear accelerator; dose; BCDTL; LAHET AB For the new high-power accelerators currently being designed, activation of the accelerator structure has became an important issue. To quantify this activation, a methodology was developed and utilized that coupled transport and depletion codes to obtain dose rate estimates at several locations near the accelerator. To perform these calculations, simplified computer models were developed from detailed engineering drawings of a typical high-power accelerator design. This research focused on the 20 and 100 MeV sections of the bridge-coupled drift tube linear (BCDTL) accelerator. The peak dose rate was found to be approximately 6.5 mR/h in the 100 MeV section near the quadrupoles at a 25 cm radius, given an assumed beam loss of 1 nA/m. This peak occurs after the longest irradiation time (1 year) and the 1 hour decay time considered for this research. It was determined that the activation was caused mostly by proton interactions and subsequent spallation products, as opposed to absorption of the generated neutrons. The worst contributors were the spallation products created by proton bombardment of iron, and the worst: component was the beam pipe, which consists mostly of iron. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Texas, Dept Mech Engn, Austin, TX 78712 USA. Texas A&M Univ, College Stn, TX 77843 USA. RP Eaton, SL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,Mail Stop K551, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012 NR 12 TC 0 Z9 0 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 MAY PY 2000 VL 168 IS 1 BP 88 EP 97 DI 10.1016/S0168-583X(99)00805-8 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 317RU UT WOS:000087241400012 ER PT J AU Charlton, WS Fearey, BL Nakhleh, CW Parish, TA Perry, RT Poths, J Quagliano, JR Stanbro, WD Wilson, WB AF Charlton, WS Fearey, BL Nakhleh, CW Parish, TA Perry, RT Poths, J Quagliano, JR Stanbro, WD Wilson, WB TI Operator declaration verification technique for spent fuel at reprocessing facilities SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE spent fuel; reprocessing; mass spectrometry; safeguards AB A verification technique for use at reprocessing facilities, which integrates existing technologies to strengthen safeguards through the use of environmental monitoring, has been developed at Los Alamos National Laboratory. This technique involves the measurement of isotopic ratios of stable noble fission gases from on-stack emissions during reprocessing of spent fuel using high-precision mass spectrometry. These results are then compared to a database of calculated isotopic ratios using a data analysis method to determine specific fuel parameters (e.g., burnup, fuel type, reactor type, etc.). These inferred parameters call be used to verify operator declarations. The integrated system (mass spectrometry, reactor modeling, and data analysis) has been validated using on-stack measurements during reprocessing of fuel from a US production reactor. These measurements led to an inferred burnup that matched the declared burnup to within 3.9%. suggesting that the current system is sufficient fur most safeguards applications. Partial system validation using gas samples from literature measurements of power reactor fuel has been reported elsewhere, This has shown that the technique developed here may have some difficulty distinguishing pressurized water reactor (PWR) from boiling water reactor (BWR) fuel; however, it consistently can distinguish light water reactor (either PWR or BWR) fuels from other reactor fuel types. Future validations will include advanced power reactor fuels (such as breeder reactor fuels) and research reactor fuels as samples become available. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Stafeguards Syst Grp NIS7, Los Alamos, NM 87545 USA. Texas A&M Univ, College Stn, TX 77843 USA. RP Charlton, WS (reprint author), Univ Calif Los Alamos Natl Lab, Stafeguards Syst Grp NIS7, Mail Stom E541, Los Alamos, NM 87545 USA. NR 31 TC 5 Z9 5 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 2000 VL 168 IS 1 BP 98 EP 108 DI 10.1016/S0168-583X(99)00633-3 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 317RU UT WOS:000087241400013 ER PT J AU Xie, ZQ Wutte, D Lyneis, CM AF Xie, ZQ Wutte, D Lyneis, CM TI Ionization efficiencies for highly charged stable and radioactive ions in the AECR-U ion source SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE high charge state ECR ion source; electron cyclotron resonance ion sources; plasma ion source; radioactive ion beams; ionization efficiency AB Ionization efficiencies for high charge state ions have been measured with the LBNL AECR-U ion source for ion beams produced from stable and radioactive gases. Various calibrated gas leaks from stable CO, CO2, O-2, Ne, Ar, CHF3, Kr and Xe were used in the measurements. Ionization efficiencies as high as 25% or higher were measured for O-16(6+) and C-12(4+) ion beams and more than 10% for high charge state stable ion beams of Ar, Kr and Xe. In addition, ionization efficiency measurements for radioactive species of C-11 and O-14 were carried out in which an efficiency of more than 10% for C-11(4+) was achieved. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Wutte, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd MS 88, Berkeley, CA 94720 USA. NR 14 TC 4 Z9 4 U1 1 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 MAY PY 2000 VL 168 IS 1 BP 117 EP 124 DI 10.1016/S0168-583X(99)00632-1 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 317RU UT WOS:000087241400015 ER PT J AU Weber, WJ AF Weber, WJ TI Models and mechanisms of irradiation-induced amorphization in ceramics SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE amorphization; radiation effects; ceramics; models ID BEAM-INDUCED AMORPHIZATION; ION-INDUCED CRYSTALLIZATION; DECAY-INDUCED AMORPHIZATION; RADIATION-DAMAGE; COMPOSITE MODEL; SILICON-CARBIDE; TEMPERATURE; ZIRCON; IMPLANTATION; RECRYSTALLIZATION AB A number of models have been developed to describe the various amorphization processes and the effects of temperature on the kinetics of amorphization. These models are reviewed and in some cases further developed. In general, these models contain a number of parameters relating to irradiation-assisted and thermal recovery processes, which make their application to existing data sets challenging. Nonetheless, general aspects of the models yield insights into the rate-limiting processes controlling the kinetics of amorphization within a given temperature regime. Several examples are used to illustrate features of the models and to highlight differences in behavior. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Weber, WJ (reprint author), Pacific NW Lab, MSIN K2-44,POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008 OI Weber, William/0000-0002-9017-7365 NR 46 TC 246 Z9 247 U1 11 U2 79 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 MAY PY 2000 VL 166 BP 98 EP 106 DI 10.1016/S0168-583X(99)00643-6 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200018 ER PT J AU Barbour, JC Knapp, JA Follstaedt, DM Mayer, TM Minor, KG Linam, DL AF Barbour, JC Knapp, JA Follstaedt, DM Mayer, TM Minor, KG Linam, DL TI The mechanical properties of alumina films formed by plasma deposition and by ion irradiation of sapphire SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE alumina; nanoindentation; irradiation; plasma-deposited; yield strength ID IMPLANTATION; TEMPERATURE; SUBSTRATE; OXIDE; AL2O3 AB This paper examines the correlation between mechanical properties and the density, phase and hydrogen content of deposited alumina layers, and compares them to those of sapphire and amorphous alumina synthesized through ion-beam irradiation of sapphire. Alumina films were deposited using electron beam evaporation of aluminum and cobombardment with O-2(+) ions (30-230 eV) from an electron-cyclotron resonance (ECR) plasma. The II content and phase were controlled by varying the deposition temperature and the ion energy. Sapphire was amorphized at 84 K by irradiation with Al and O ions (in stoichiometric ratio) to a defect level of 4 dpa in order to form an amorphous layer 370 nm thick. Nanoindentation was performed to determine the elastic modulus, yield strength and hardness of all materials. Sapphire and amorphized sapphire have a higher density and exhibit superior mechanical properties in comparison to the deposited alumina films. Density was determined to be the primary factor affecting the mechanical properties, which showed only a weak correlation to the hydrogen content. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87123 USA. RP Barbour, JC (reprint author), Sandia Natl Labs, 1515 Eubank SE, Albuquerque, NM 87123 USA. NR 18 TC 21 Z9 22 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 2000 VL 166 BP 140 EP 147 DI 10.1016/S0168-583X(99)00648-5 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200024 ER PT J AU Monge, MA Gonzalez, R Santiuste, JEM Pareja, R Chen, Y Kotomin, EA Popov, AI AF Monge, MA Gonzalez, R Santiuste, JEM Pareja, R Chen, Y Kotomin, EA Popov, AI TI Photoconversion of F+ centers in neutron-irradiated MgO SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE F centre; MgO; luminescence; interstitial; radiation damage ID CRYSTALS; DIFFUSION AB In neutron-irradiated MgO crystals, experiments and theory demonstrate that photon excitation of the positively charged anion vacancies (F+ centers) at 5.0 eV releases holes that are subsequently trapped at V-type centers, which are cation vacancies charge-compensated by impurities, such as Al3+, F, and OH ions. A photoconversion mechanism occurs very likely via electron transfer to F+ centers from the quasi-local states which are induced in the valence band. INDO quantum chemical simulations of Fi centers confirmed the appearance of two induced quasi-local states located at 1.2 and 2.0 eV below the top of the valence band. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Carlos III Madrid, Dept Fis, Madrid 28911, Spain. US DOE, Germantown, MD 20874 USA. Latvian State Univ, Inst Solid State Phys, LV-1063 Riga, Latvia. RP Popov, AI (reprint author), Univ Carlos III Madrid, Dept Fis, Madrid 28911, Spain. RI Dep Theor Physics, Computer Modeling/E-6336-2013; Kotomin, Eugene/B-8070-2013; Popov, Anatoli /E-8828-2010; Munoz Santiuste, Juan/K-7461-2015; OI Kotomin, Eugene/0000-0002-8122-6276; Popov, Anatoli /0000-0003-2795-9361; Munoz Santiuste, Juan/0000-0001-6286-139X; Monge, Miguel A./0000-0002-0425-6789 NR 16 TC 18 Z9 18 U1 1 U2 11 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 MAY PY 2000 VL 166 BP 220 EP 224 DI 10.1016/S0168-583X(99)00751-X PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200038 ER PT J AU Gritsyna, VT Afanasyev-Charkin, IV Kobyakov, VA Voitsenya, TI Sickafus, KE AF Gritsyna, VT Afanasyev-Charkin, IV Kobyakov, VA Voitsenya, TI Sickafus, KE TI Charge carrier rearrangement in spinel crystals irradiated at low temperatures SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE spinel crystals; optical centers; thermoluminescence; isothermal luminescence ID MGAL2O4; THERMOLUMINESCENCE; RADIATION; SPECTRA AB The results of an investigation of thermolurninescence (TL) in nominally pure MgAl2O4 spinel single crystals in the temperature range between 80-670 K are presented. For a heating rate of 0.21 Ws, TL spectra exhibit glow peaks in three distinct temperature ranges: 100 160, 270 370 and 470 670 K. The most prominent peaks are at 115, 140, 305, 335, 525, 570 and 605 K. The locations of the temperature maxima, as well as the intensity of the peaks, vary depending on the treatment of the crystals, the type of irradiation and the temperature of irradiation. Measurements of the glow peaks at different emission wavelengths and the use of partial bleaching and isothermal decay techniques for TL, allowed us to propose mechanisms for charge carrier rearrangement at lattice defects and impurity ions, during irradiation and subsequent heating. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Kharkov State Univ, Dept Phys & Technol, UA-310077 Kharkov, Ukraine. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Gritsyna, VT (reprint author), Kharkov State Univ, Dept Phys & Technol, Svoboda Sq 4, UA-310077 Kharkov, Ukraine. NR 16 TC 5 Z9 5 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 MAY PY 2000 VL 166 BP 244 EP 249 DI 10.1016/S0168-583X(99)00660-6 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200042 ER PT J AU Li, FX Ishimaru, M Lu, P Afanasyev-Charkin, IV Sickafus, KE AF Li, FX Ishimaru, M Lu, P Afanasyev-Charkin, IV Sickafus, KE TI Damage evolution in Xe-ion irradiated rutile (TiO2) single crystals SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE ion radiation effects; rutile (TiO2); crystal defects; amorphization; ion scattering; ion channeling; transmission electron microscopy; electron diffraction ID LATTICE DISORDER; IMPLANTED TIO2; CONDUCTIVITY AB Rutile (TiO2) single crystals with (110) and (100) orientations were irradiated with 360 keV Xe-24 ions at 300 K to fluences ranging from 1 x 10(17) to 5 x 10(20) Xe/m(2). Irradiated samples were analyzed using Rutherford backscattering spectroscopy combined with ion channeling analysis (RBS/C) and transmission electron microscopy (TEM). RBS/C results showed that much of the instantaneous displacement damage produced under ion irradiation is recovered under ambient temperature irradiation conditions. Upon irradiation to a fluence of 2 x 10(19) Xe/m(2), the radiation damage-induced microstructure was observed by TEM to consist of three distinct layers: (1) a layer near surface (thickness about 12 nm) exhibiting relatively homogeneous TEM contrast; (2) a second layer with a low density of relatively large-sized defects; and (3) a third layer consisting of a high concentration of small defects. After the fluence was increased to 5 x 10(19) Xe/m(2), a buried amorphous layer was observed by TEM. The thickness of the amorphous layer was found to increase with increasing Xe ion fluence. The uppermost damage layer, which accounts for the surface subpeak in RBS/C spectra, was found to be polygonized by ion irradiation. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. New Mexico Inst Min & Technol, Dept Mat Engn, Socorro, NM 87801 USA. Kyushu Univ, Dept Mat Sci & Engn, Fukuoka 8128581, Japan. RP Sickafus, KE (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, POB 1663, Los Alamos, NM 87545 USA. NR 17 TC 23 Z9 23 U1 1 U2 9 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 MAY PY 2000 VL 166 BP 314 EP 321 DI 10.1016/S0168-583X(99)00672-2 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200055 ER PT J AU Park, B Weber, WJ Corrales, LR AF Park, B Weber, WJ Corrales, LR TI Molecular dynamics study of the threshold displacement energy in MgO SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE displacement threshold energy; MgO; molecular dynamics ID COMPUTER-SIMULATION; DEFECT PRODUCTION; POINT-DEFECTS; CERAMICS AB Molecular dynamics (MD) simulations were used to obtain threshold displacement energies (Ed) of atoms along specific directions in MgO. In the simulation, an atom in the center of the cell was given kinetic energy along a specific crystallographic direction. The positions and site potential energies of the primary knock-on atom (pka) and all neighboring atoms were monitored as a function of time. In this work, the minimum displacement energies that formed stable Frenkel pair defects were determined to be 90 +/- 2 eV along the [131] direction for magnesium and 67 +/- 3 eV along the [121] direction for oxygen. The MD simulations reveal that atomic displacement events consist of replacement collision sequences in addition to the production of Frenkel pairs. (C) 2000 Elsevier Science B.V, All rights reserved. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Corrales, LR (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, K8-91,POB 999,902 Batelle Blvd, Richland, WA 99352 USA. RI Weber, William/A-4177-2008 OI Weber, William/0000-0002-9017-7365 NR 18 TC 15 Z9 15 U1 1 U2 8 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 MAY PY 2000 VL 166 BP 357 EP 363 DI 10.1016/S0168-583X(99)00694-1 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200062 ER PT J AU Jiang, W Weber, WJ Thevuthasan, S Grotzschel, R AF Jiang, W Weber, WJ Thevuthasan, S Grotzschel, R TI Irradiation effects and thermal annealing behavior in H-2(+)-implanted 6H-SiC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE damage accumulation and recovery; blistering; hydrogen profiles; 6H-SiC ID ION BEAM IRRADIATION; SILICON-CARBIDE; SIC CRYSTALS; DAMAGE; ACCUMULATION; TRANSITION; RECOVERY; HE+ AB RBS/channeling (RBS/C) has been used to study the accumulation and isochronal recovery of disorder on the Si sublattice in 6H-SiC single crystals irradiated with 100 keV H-2(+) ions at 100 and 300 K. The disorder at the damage peak shows a sigmoidal dependence on ion fluence for both irradiation temperatures. Dramatic simultaneous recovery is observed for the irradiation at 300 K. At fluences below 1.5 x 10(16) H+ cm(-2), isochronal recovery occurs gradually over a wide temperature range. Above a fluence of 1.5 x 10(17) H+ cm(2), a near amorphous state is produced, and significant recovery does not occur. At intermediate fluences between 4.5 x 10(16) and 1.0 x 10(17) H+ cm(-2), damage recovery occurs more rapidly between 300 and 670 K. Further annealing at 1070 K results in the formation of blisters. Hydrogen depth profiles at 100 and 300 K; are comparable and are well predicted by SRIM-97 simulations. Hydrogen release of about 30% is observed for silicon carbide (SiC) irradiated at 100 K and subsequently annealed at 1070 It for 20 min. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Res Ctr Rossendorf, D-01314 Dresden, Germany. RP Jiang, W (reprint author), Pacific NW Natl Lab, POB 999,MS K8-93,902 Battelle Blvd, Richland, WA 99352 USA. RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 15 TC 21 Z9 23 U1 1 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 MAY PY 2000 VL 166 BP 374 EP 378 DI 10.1016/S0168-583X(99)01050-2 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200064 ER PT J AU Ishimaru, M Dickerson, RM Sickafus, KE AF Ishimaru, M Dickerson, RM Sickafus, KE TI Ion beam synthesis of buried oxide layers in silicon carbide SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE SiC; semiconductor-on-insulator (SOI); STEM; EDX; EELS; elemental mapping ID MICROSTRUCTURAL EVOLUTION; IMPLANTED SILICON AB A field emission gun scanning transmission electron microscope equipped with an energy-dispersive X-ray spectrometer (EDX) and an electron energy loss spectrometer (EELS) has been used to characterize the microstructures, elemental distributions, and chemical bonding states of oxygen ion implanted silicon carbide (SiC). 6H-SiC substrates with the (0001) orientation were implanted with 180 keV oxygen ions at 650 degrees C to fluences of 0.7 x 10(18) and 1.4 x 10(18) cm(-2). A continuous amorphous layer is formed in the as-implanted state under these irradiation conditions. The amorphous layer is uniform in the low-dose sample, while it consists of three layers in the high-dose one. EDX maps of elemental distributions suggest that the layered structure in the latter sample originates from compositional fluctuations of silicon, carbon and oxygen. EELS measurements suggest that the amorphous regions in the high-dose sample consist of well-defined SiO2 layer which is accompanied by sp(2)-bonded carbon. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Kyushu Univ, Dept Mat Sci & Engn, Fukuoka 8128581, Japan. RP Ishimaru, M (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, POB 1663, Los Alamos, NM 87545 USA. NR 10 TC 9 Z9 9 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 MAY PY 2000 VL 166 BP 390 EP 394 DI 10.1016/S0168-583X(99)01057-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200067 ER PT J AU Handy, EM Rao, MV Holland, OW Jones, KA Chi, PH AF Handy, EM Rao, MV Holland, OW Jones, KA Chi, PH TI Acceptor ion-implantation in SiC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE SiC; ion-implantation; acceptors; annealing; activation AB Single and multiple energy Al, B and Ga ion-implantations were performed into n-type 6H-SiC epitaxial layers. Empirical formulae for the range statistics of the implant depth distributions in the energy range 50 keV-4 MeV were developed by analyzing the experimental secondary ion mass spectrometry (SIMS) implant depth profiles. The Al and Ga implants were electrically activated at an annealing temperature of 1500 degrees C, but the B implants required an annealing temperature of 1650 degrees C. In this study annealings were performed by using AlN or graphite encapsulant. The Al and Ga implants are thermally stable but the B implants showed redistribution during annealing. (C) 2000 Elsevier Science B.V. All rights It served. C1 George Mason Univ, Fairfax, VA 22030 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. USA, Res Lab, Adelphi, MD 20783 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Rao, MV (reprint author), George Mason Univ, Fairfax, VA 22030 USA. NR 10 TC 1 Z9 1 U1 1 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 MAY PY 2000 VL 166 BP 395 EP 398 DI 10.1016/S0168-583X(99)00867-8 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200068 ER PT J AU Weber, WJ Jiang, W Thevuthasan, S AF Weber, WJ Jiang, W Thevuthasan, S TI Defect annealing kinetics in irradiated 6H-SiC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE silicon carbide; defects; annealing; ion irradiation; RBS/channeling ID DAMAGE; ACCUMULATION AB Isochronal and isothermal annealing of ion-irradiation damage on the Si sublattice in 6H SiC has been investigated experimentally by in situ Rutherford backscattering spectrometry in channeling geometry (RBS/C). At low ion fluences corresponding to dilute concentrations of irradiation-induced defects, complete recovery of disorder on the Si sublattice can occur below room temperature. The implantation of helium impedes the defect recovery processes at low temperatures. Below room temperature, the thermal recovery of defects on the Si sublattice has an activation energy on the order of 0.25 +/- 0.1 eV. Recovery of disorder on the Si sublattice above 570 K has an activation energy on the order of 1.5 +/- 0.3 eV. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Weber, WJ (reprint author), Pacific NW Natl Lab, MSIN K2-44,POB 999, Richland, WA 99352 USA. EM bill.weber@pnl.gov RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 12 TC 27 Z9 28 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 2000 VL 166 BP 410 EP 414 DI 10.1016/S0168-583X(99)00868-X PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200071 ER PT J AU Song, JY Jonsson, H Corrales, LR AF Song, JY Jonsson, H Corrales, LR TI Self-trapped excitons in quartz SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE self-trapped excitons; quartz; density functional theory ID TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; ALPHA-QUARTZ; SILICON DIOXIDE; AB-INITIO; MOLECULAR-DYNAMICS; OXYGEN VACANCIES; SIO2; DEFECTS; GERMANIUM AB Triplet-state electronic excitations in quartz were studied using density functional theory (DFT). By using periodic boundary conditions, the lattice response and electronic structure relaxations can be determined in the bulk. Several self-trapped exciton (STE) states have been discovered, in addition to the oxygen-distorted state, which was originally predicted 10 years ago. One of these stales is a silicon-distorted state that lies energetically close to the oxygen-distorted state. The results reveal that these two major STE states are likely responsible for two distinct luminescence bands. The luminescence energies for STE states of impurities and intrinsic defects were also determined. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Washington, Dept Chem, Seattle, WA 98195 USA. RP Corrales, LR (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999,MS K8-91,902 Batelle Blvd, Richland, WA 99352 USA. EM rene.corrales@pnl.gov RI Jonsson, Hannes/G-2267-2013 OI Jonsson, Hannes/0000-0001-8285-5421 NR 30 TC 14 Z9 14 U1 1 U2 4 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 MAY PY 2000 VL 166 BP 451 EP 458 DI 10.1016/S0168-583X(99)00785-5 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200078 ER PT J AU Sarkisov, SS Curley, MJ Williams, EK Ila, D Svetchnikov, VL Zandbergen, HW Zykov, GA Banks, C Wang, JC Poker, DB Hensley, DK AF Sarkisov, SS Curley, MJ Williams, EK Ila, D Svetchnikov, VL Zandbergen, HW Zykov, GA Banks, C Wang, JC Poker, DB Hensley, DK TI Nonlinear optical waveguides produced by MeV ion implantation in LiNbO3 SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE nano-cluster composites; quantum dots; ion implantation; nonlinear waveguides ID SILICA AB We analyze microstructure, linear and nonlinear optical properties of planar waveguides produced by implantation of MeV Ag ions into LiNbO3. Linear optical properties are described by the parameters of waveguide propagation modes and optical absorption spectra, Nonlinear properties are described by the nonlinear refractive index, Operation of the implanted crystal as an optical waveguide is due to modification of the linear refractive index of the implanted region. The samples as implanted do not show any light-guiding. The implanted region has amorphous and porous microstructure with the refractive index lower than the substrate. Heat treatment of the implanted samples produces planar light-guiding layer near the implanted surface. High-resolution electron microscopy reveals re-crystallization of the host between the surface and the nuclear stopping region in the form of randomly oriented crystalline grains. They make up a light-guiding layer isolated from the bulk crystal by the nuclear stopping layer with low refractive index. Optical absorption of the sample as implanted has a peak at 430 nm. This peak is due to the surface plasmon resonance in nano-clusters of metallic silver. Heat treatment of the samples shifts the absorption peak to 545 nm. This is more likely due to the increase of the refractive index back to the value for the crystalline LiNbO3. The nonlinear refractive index of the samples at 532 nm (of the order of 10(-10) cm(2) W-1) was measured with the Z-scan technique using a picosecond laser source. Possible applications of the waveguides include ultra-fast photonic switches and modulators, (C) 2000 Elsevier Science B.V, All rights reserved. C1 Alabama A&M Univ, Dept Nat & Phys Sci Phys, Normal, AL 35762 USA. Alabama A&M Univ, Ctr Irradiat Mat, Normal, AL 35762 USA. Delft Univ Technol, Mat Sci Lab, Natl Ctr HREM, NL-2628 AL Delft, Netherlands. Inst Met Phys, Dept Superconduct, UA-252142 Kiev, Ukraine. Kiev State Univ, Dept Radiophys, UA-252017 Kiev, Ukraine. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Sarkisov, SS (reprint author), Alabama A&M Univ, Dept Nat & Phys Sci Phys, POB 1268, Normal, AL 35762 USA. RI Hensley, Dale/A-6282-2016 OI Hensley, Dale/0000-0001-8763-7765 NR 15 TC 20 Z9 20 U1 2 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 MAY PY 2000 VL 166 BP 750 EP 757 DI 10.1016/S0168-583X(99)01209-4 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200131 ER PT J AU Potter, BG Simmons-Potter, K AF Potter, BG Simmons-Potter, K TI Photosensitive point defects in optical glasses: Science and applications SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE photosensitivity; point defects; glass; optical phenomena; photonics ID PLANAR WAVE-GUIDES; REFRACTIVE-INDEX CHANGES; BRAGG GRATINGS; EXCIMER-LASER; THIN-FILMS; GEO2-SIO2 GLASSES; DOPED SILICA; ULTRAVIOLET-IRRADIATION; GERMANOSILICATE FIBERS; ABSORPTION BAND AB The understanding and manipulation of the point defect structure in oxide glasses have been critical to the enhanced performance and reliability of optical-fiber-based, photosensitive photonic devices that currently find widespread application in telecommunications and remote sensing technologies. We provide a brief review of past research investigating photosensitive mechanisms in germanosilicate glasses, the primary material system used in telecommunications fibers. This discussion motivates an overview of ongoing work within our laboratories to migrate photosensitive glass technologies to a planar format for integrated photonic applications. Using reactive-atmosphere, RF-magnetron sputtering, we have demonstrated control of glass defect structure during synthesis, thereby controlling both the material photosensitivity (i.e., dispersion and magnitude of the refractive index change) and its environmental stability. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Potter, BG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 47 TC 24 Z9 25 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 MAY PY 2000 VL 166 BP 771 EP 781 DI 10.1016/S0168-583X(99)00864-2 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200134 ER PT J AU Ila, D Williams, EK Zimmerman, RL Poker, DB Hensley, DK AF Ila, D Williams, EK Zimmerman, RL Poker, DB Hensley, DK TI Radiation induced nucleation of nanoparticles in silica SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE ion implantation; nanocrystals; optical materials ID MEV ION-IMPLANTATION; COLLOIDAL AU; FUSED-SILICA; NANOCLUSTERS; GLASS AB There is a threshold implantation dose, after which some of the implanted species will tend to spontaneously form nanoclusters, over-dose-implantation. Similarly, then is a threshold implantation dose for the implanted species in a layer of the host material, such that after high temperature annealing the nanoclusters can nucleate before the implanted material can dissolve in the host material (during such heat treatments). In this paper, we present the results of our investigation of producing nanoclusters of gold in silica at fluences of two orders of magnitude less than what is traditionally used. This is accomplished by implanting 2.0 MeV Au into silica followed by MeV bombardment by MeV Si ions. This process was used to reduce the threshold implantation dose by at least two orders of magnitude. To follow the formation of nanoclusters, we used both indirect measurement methods such as optical absorption spectrophotometry (non-destructive), and direct methods such as transmission electron microscopy (destructive). The size of the nanoclusters, ranging from 1 to 10 nm, are controlled by the implantation dose and by the total electronic energy deposited by each post-bombarding ion in the implanted layer. We will show how and at what concentrations species such as gold nucleates to form nanoclusters, either by induced strain or by radiation-enhanced nucleation at a dose below that needed for spontaneous nanocluster formation. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Alabama A&M Univ, Ctr Irradiat Mat, Dept Naur & Phys Sci, Normal, AL 35762 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Ila, D (reprint author), Alabama A&M Univ, Ctr Irradiat Mat, Dept Naur & Phys Sci, POB 1447, Normal, AL 35762 USA. RI Hensley, Dale/A-6282-2016 OI Hensley, Dale/0000-0001-8763-7765 NR 14 TC 23 Z9 24 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 MAY PY 2000 VL 166 BP 845 EP 850 DI 10.1016/S0168-583X(99)00794-6 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200146 ER PT J AU Zimmerman, RL Ila, D Williams, EK Gasic, B Elsamadicy, A Evelyn, AL Poker, DB Hensley, DK Larkin, DJ AF Zimmerman, RL Ila, D Williams, EK Gasic, B Elsamadicy, A Evelyn, AL Poker, DB Hensley, DK Larkin, DJ TI Gold, silver and copper nanocrystal formation in SiC by MeV implantation SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 10th International Conference on Radioation Effects in Insulators (REI-10) CY JUL 18-23, 1999 CL JENA, GERMANY SP Deutsch Forsch Gemeinsch, Friedrich Schiller Univ Jena, Thruinger Minist Wissensch, Forsch & Kultur, Elsevier Sci BV, Amsterdam, High Voltage Engn Europa BV, Amersfoort, Carl Zeiss Jena GmbH, Jena, Jenoptik AG, Jena, Layertec GmbH, Mellingen, VACOM GmbH, Jena, JENION, Jena, PINK GmbH, Wertheim DE implantation; nanocrystals; nonlinear optical materials ID ION-IMPLANTATION; SILICA; NANOCLUSTERS AB Nanoclusters gold, silver and copper are produced in 6H-SiC by implanting 1.0 MeV Au, 2.0 MeV Ag and 2.0 MeV Cu into the Si face of SiC at room or elevated temperature followed by annealing at various temperatures. The absorption bands for each type of metal nanoclusters in SIC were determined using optical absorption spectrophotometry, Elevated temperature implantation reduces optical absorption due to ion implantation induced defects. Using the Mie theory, we determined the index of refraction in the implanted volume. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Alabama A&M Univ, Ctr Irradiat Mat, Normal, AL 35762 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. NASA, Gleen Res Ctr, Cleveland, OH 44135 USA. RP Zimmerman, RL (reprint author), Alabama A&M Univ, Ctr Irradiat Mat, POB 1447, Normal, AL 35762 USA. RI Hensley, Dale/A-6282-2016 OI Hensley, Dale/0000-0001-8763-7765 NR 13 TC 15 Z9 17 U1 3 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 MAY PY 2000 VL 166 BP 892 EP 896 DI 10.1016/S0168-583X(99)01040-X PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 320VU UT WOS:000087422200154 ER PT J AU Yu, JF Zhang, RP Dai, XL Min, XF Xu, JY Hu, WQ Yin, DZ Zhou, W Xie, H Wang, YX Knapp, FF AF Yu, JF Zhang, RP Dai, XL Min, XF Xu, JY Hu, WQ Yin, DZ Zhou, W Xie, H Wang, YX Knapp, FF TI Intratumoral injection with [Re-188]rhenium sulfide suspension for treatment of transplanted human liver carcinoma in nude mice SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE [Re-188]thenium sulfide; suspension; intratumoral injection; tumor inhibiting ratio; hepatoma ID INTRA-TUMOR INJECTION; RADIATION SYNOVECTOMY AB Hepatocellular carcinoma (HCC) is one of the most common malignancies in China. Direct intratumoral injection of nonremovable radioactive material has been widely studied because it could deliver high doses of radiation to target sites and minimize radiation leakage to non-target organs or tissues. Thirty nude mice bearing SMMC 7721 human liver carcinoma were used for the biodistribution study after intratumoral injection of [Re-188]rhenium sulfide suspension or sodium [Re-188]perrhenate solution. Another 30 tumor-bearing mice were divided into six groups, four groups of which were treated with a 0.1 ml [Re-188]rhenium sulfide suspension at doses of 3.7, 7.4, 18.5, 29.6 MBq by a single intratumoral injection. For control studies, to study the tumor inhibiting ratio, the remaining two groups were injected with nonradioactive rhenium sulfide suspension and Hanks' balanced salt solution, respectively. The injections were repeated 6 days later, The retention percentages of radioactivity (%ID) in tumors injected with [Re-188]rhenium sulfide suspension were 90.96 + 6.63%, 86.09 +/- 22.58% and 87.62 +/- 13.97% at 1, 24 and 48 h, respectively. Tumor inhibition ratios are as high as 89% when the outer space of tumor (0.5-0.6 cm from center) received about 507.6 Gy doses. Intratumoral injection of [Re-188]rhenium sulfide suspension results in high tumor retention indicating this approach has strong potential for the treatment of hepatic carcinoma, NUCL MED BIOL 27;4:347-352, 2000. (C) 2000 Elsevier Science Inc. All rights reserved. C1 Acad Sinica, Shanghai Inst Nucl Res, Shanghai 201800, Peoples R China. Shanghai Inst Cell Biol, Shanghai, Peoples R China. Oak Ridge Natl Lab, Nucl Med Grp, Oak Ridge, TN USA. RP Yu, JF (reprint author), Acad Sinica, Shanghai Inst Nucl Res, POB 800-204, Shanghai 201800, Peoples R China. NR 12 TC 5 Z9 6 U1 1 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD MAY PY 2000 VL 27 IS 4 BP 347 EP 352 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 345PG UT WOS:000088823900004 ER PT J AU Ding, YS Liu, N Wang, T Marecek, J Garza, V Ojima, I Fowler, JS AF Ding, YS Liu, N Wang, T Marecek, J Garza, V Ojima, I Fowler, JS TI Synthesis and evaluation of 6-[F-18]fluoro-3-(2(S)azetidinylmethoxy)pyridine as a PET tracer for nicotinic acetylcholine receptors SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE nicotinic acetylcholine receptors; ABT-594; A-85380; positron emission tomography; trimethylammonium; nucleophilic aromatic substitution; F-18 ID EMISSION-TOMOGRAPHY LIGAND; BINDING-PROPERTIES; POTENT; (R)-5-(2-AZETIDINYLMETHOXY)-2-CHLOROPYRIDINE; DERIVATIVES; RADIOLIGAND; RADIOTRACER; AFFINITY; TOXICITY; ABT-594 AB Both ABT-594 ((R)-2-chloro-5-(2-azetidinylmethoxy)pyridine) and A-85380 (3-[2(S)-2-azetidinylmethoxy]pyridine), novel nicotinic agonists that possess potent non-opioid analgesic properties, have high affinity for neuronal nicotinic acetylcholine receptors (nAChR) but do not elicit the pronounced toxicity of epibatidine. 6-[F-18]Fluoro-3-(2(S)-azetidinylmethoxy) (6-[F-18]fluoro-A-85380), a F-18 labeled analogue of these two compounds, is therefore a promising radioligand for positron emission tomography (PET) studies in humans. The use of trimethylammonium as a leaving group in nucleophilic aromatic substitution reactions has proven to be a versatile and efficient strategy, and offers several advantages over other leaving groups. Here, we report the synthetic strategy for the preparation of a precursor, as a trimethylammonium iodide salt, and its use in the radiosynthesis to 6-[F-18]fluoro-A-85380. Preliminary compartative PET studies of 6-[F-18]fluoro-A-85380 and 2-[F-18]fluoro-A-85380 were carried out in baboon to examine their suitability as tracers for studying nAChR system. NUCL MED BIOL 27;4: 381-389, 2000. (C) 2000 Elsevier Science Inc. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. RP Ding, YS (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NINDS NIH HHS [NS-15380] NR 29 TC 43 Z9 44 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD MAY PY 2000 VL 27 IS 4 BP 381 EP 389 DI 10.1016/S0969-8051(00)00094-9 PG 9 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 345PG UT WOS:000088823900010 PM 10938474 ER PT J AU Fujii, Y Iwamoto, A Fukahori, T Ohnuki, T Nakagawa, M Hidaka, H Oura, Y Moller, P AF Fujii, Y Iwamoto, A Fukahori, T Ohnuki, T Nakagawa, M Hidaka, H Oura, Y Moller, P TI The nuclear interaction at Oklo 2 billion years ago SO NUCLEAR PHYSICS B LA English DT Article DE unified theories; time-dependent constants; natural reactors; Okio phenomenon ID COSMOLOGICAL CONSTANT; TIME; REACTORS; LIMITS AB We re-examine the effort to constrain the time variability of the coupling constants of the fundamental interactions by studying the anomalous isotopic abundance of Sm observed at the remnants of the natural reactors which were in operation at Oklo about 2 billion years ago, in terms of a possible deviation of the resonance energy from the value observed today. We rely on new samples that were carefully collected to minimize natural contamination and also on a careful temperature estimate of the reactors. We obtain the upper bound (-0.2 +/- 0.8) X 10(-17) y(-1) on the fractional rate of change of the electromagnetic as well as the strong interaction coupling constants. Our result basically agrees with and even suggests some improvement of the result due recently to Damour and Dyson. Strictly speaking, however, we find another choice of the resonance energy shift indicating a non-zero time variation of the constants. However, we find a rather strong but still tentative indication that this non-null range can be ruled out by including Gd data, for which it is essential to take the effect of contamination into account. (C) 2000 Elsevier Science B.V, All rights reserved. C1 Nihon Fukushi Univ, Handa, Aichi 4750012, Japan. Univ Tokyo, Inst Cosm Ray Res, Tanashi, Tokyo 1888502, Japan. Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. Hiroshima Univ, Dept Earth & Planetary Syst Sci, Hiroshima 7398526, Japan. Tokyo Metropolitan Univ, Dept Chem, Hachioji, Tokyo 1920397, Japan. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Fujii, Y (reprint author), Nihon Fukushi Univ, Handa, Aichi 4750012, Japan. RI Hidaka, Hiroshi/A-8490-2012 NR 30 TC 178 Z9 180 U1 5 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY 1 PY 2000 VL 573 IS 1-2 BP 377 EP 401 DI 10.1016/S0550-3213(00)00038-9 PG 25 WC Physics, Particles & Fields SC Physics GA 306MR UT WOS:000086600900020 ER PT J AU Wischnewski, R Andres, E Bai, X Barouch, G Barwick, S Bay, R Becker, K Bergstrom, L Bertrand, D Besson, D Biron, A Booth, J Botner, O Bouchta, A Carius, S Carlson, M Chinowsky, W Chirkin, D Conrad, J Cowen, DF Costa, C Dalberg, E Desiati, P Dewulf, J Deyoung, T Doksus, P Edsjo, J Ekstrom, P Feser, T Frichter, G Gaisser, T Goldschmidt, A Goobar, A Hallgren, A Halzen, F Hardtke, R Hellwig, M Hill, G Hulth, P Hundertmark, S Jacobsen, J Karle, A Kim, J Koepke, L Kowalski, M Kravchenko, I Lamoureux, J Leich, H Leuthold, M Lindahl, P Liss, T Loaiza, P Lowder, D Ludvig, J Marciniewski, P Matis, H Miller, T Miocinovic, P Mock, P Morse, R Neunhoeffer, T Newcomer, M Niessen, P Nygren, D De los Heros, CP Porrata, R Price, P Przybylski, G Rawlins, K Rhode, W Richter, S Rodriguez, J Romenesko, P Ross, D Rubinstein, H Sander, H Schafer, U Schmidt, T Schneider, E Schwarz, R Schwendicke, U Silvestri, A Smoot, G Solarz, M Spiczak, G Spiering, C Starinski, N Steffen, P Stokstad, R Streicher, O Taboada, I Thollander, L Thon, T Tilav, S Vander Donckt, M Walck, C Wiebusch, C Woschnagg, K Wu, W Yodh, G Young, S AF Wischnewski, R Andres, E Bai, X Barouch, G Barwick, S Bay, R Becker, K Bergstrom, L Bertrand, D Besson, D Biron, A Booth, J Botner, O Bouchta, A Carius, S Carlson, M Chinowsky, W Chirkin, D Conrad, J Cowen, DF Costa, C Dalberg, E Desiati, P Dewulf, J Deyoung, T Doksus, P Edsjo, J Ekstrom, P Feser, T Frichter, G Gaisser, T Goldschmidt, A Goobar, A Hallgren, A Halzen, F Hardtke, R Hellwig, M Hill, G Hulth, P Hundertmark, S Jacobsen, J Karle, A Kim, J Koepke, L Kowalski, M Kravchenko, I Lamoureux, J Leich, H Leuthold, M Lindahl, P Liss, T Loaiza, P Lowder, D Ludvig, J Marciniewski, P Matis, H Miller, T Miocinovic, P Mock, P Morse, R Neunhoeffer, T Newcomer, M Niessen, P Nygren, D De los Heros, CP Porrata, R Price, P Przybylski, G Rawlins, K Rhode, W Richter, S Rodriguez, J Romenesko, P Ross, D Rubinstein, H Sander, H Schafer, U Schmidt, T Schneider, E Schwarz, R Schwendicke, U Silvestri, A Smoot, G Solarz, M Spiczak, G Spiering, C Starinski, N Steffen, P Stokstad, R Streicher, O Taboada, I Thollander, L Thon, T Tilav, S Vander Donckt, M Walck, C Wiebusch, C Woschnagg, K Wu, W Yodh, G Young, S TI The AMANDA Neutrino Detector - Status report SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 6th Topical Seminar on Neutrino and Astroparticle Physics CY MAY 17-21, 1999 CL PISA, ITALY SP Univ Bologna, Univ Firenze, Inst Nazl Fis Nucleare, Soc Italiana Fis, Regione Toscana, Cassa Risparmio San Miniato, CAEN, Costruzioni Apparecchiat Elettro, Nucleari AB The first stage of the AMANDA High Energy Neutrino Detector at the South Pole, the 302 PMT array AMANDA-B10, is taking data since 1997. We describe results on atmospheric neutrinos, limits on indirect WIMP detection, seasonal muon flux variation, relativistic monopole flux limits, a search for gravitational collapse neutrinos, and a depth scan of the optical ice properties. The next stage 19-string detector AMANDA-II with similar to 650 PMTs will be completed in spring 2000. C1 DESY, Inst High Energy Phys, Zeuthen, Germany. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Calif Irvine, Dept Phys, Irvine, CA 92717 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Wuppertal, Dept Phys, Wuppertal, Germany. Stockholm Univ, Dept Phys, S-10691 Stockholm, Sweden. ULB, IIHE, Brussels, Belgium. Univ Kansas, Lawrence, KS 66045 USA. Univ Uppsala, Dept Phys, Uppsala, Sweden. Kalmar Univ, Dept Phys, Kalmar, Sweden. Lawrence Berkeley Lab, Berkeley, CA USA. Univ Penn, Dept Phys, Philadelphia, PA 19104 USA. Univ Mainz, D-6500 Mainz, Germany. Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. RP Wischnewski, R (reprint author), DESY, Inst High Energy Phys, Zeuthen, Germany. RI Botner, Olga/A-9110-2013; Loaiza, Pia/D-5861-2013; Wiebusch, Christopher/G-6490-2012; Kowalski, Marek/G-5546-2012; Hundertmark, Stephan/A-6592-2010; Hallgren, Allan/A-8963-2013 OI Streicher, Ole/0000-0001-7751-1843; Perez de los Heros, Carlos/0000-0002-2084-5866; Wiebusch, Christopher/0000-0002-6418-3008; NR 11 TC 3 Z9 3 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2000 VL 85 BP 141 EP 145 DI 10.1016/S0920-5632(00)00497-7 PG 5 WC Physics, Particles & Fields SC Physics GA 313UD UT WOS:000087016900023 ER PT J AU Monfardini, A Alessandrello, A Beeman, JW Brofferio, C Cremonesi, O Fiorini, E Giuliani, A Haller, EE Margesin, B Nucciotti, A Pavan, M Pessina, G Pignatel, G Previtali, E Zanotti, L Zen, M AF Monfardini, A Alessandrello, A Beeman, JW Brofferio, C Cremonesi, O Fiorini, E Giuliani, A Haller, EE Margesin, B Nucciotti, A Pavan, M Pessina, G Pignatel, G Previtali, E Zanotti, L Zen, M TI Microbolometers for high resolution x-ray spectroscopy and neutrino mass measurement SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 6th Topical Seminar on Neutrino and Astroparticle Physics CY MAY 17-21, 1999 CL PISA, ITALY SP Univ Bologna, Univ Firenze, Inst Nazl Fis Nucleare, Soc Italiana Fis, Regione Toscana, Cassa Risparmio San Miniato, CAEN, Costruzioni Apparecchiat Elettro, Nucleari ID ENVIRONMENTAL FINE-STRUCTURE; RE-187; DECAY; SPECTRA AB The low-Q Re-187 forbidden bets transition is studied by means of a microbolometers array in order to get a direct limit on the <(nu)over bar>(e) mass. The achievable limit of the on-the-shelf small array (ten detectors) in one year measure acquisition time is less than 10eV/c(2). Silicon and Germanium thermistors are being developed also for high resolution x-ray spectroscopy; an excellent energy resolution of 5.4eV in the 6keV region has been achieved. This represent the best published result of an Energy Dispersive Sensor (EDS) in this spectral band. C1 Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci, Berkeley, CA 94720 USA. Univ Trento, IRST, I-38050 Povo, TN, Italy. Univ Trento, Dipartimento Ingn Mat, I-38050 Povo, TN, Italy. RP Monfardini, A (reprint author), Univ Milan, Dipartimento Fis, Via Celoria 16, I-20133 Milan, Italy. RI Nucciotti, Angelo/I-8888-2012; Margesin, Benno/K-5826-2015; OI Nucciotti, Angelo/0000-0002-8458-1556; Margesin, Benno/0000-0002-1120-3968; pavan, maura/0000-0002-9723-7834; Pessina, Gianluigi Ezio/0000-0003-3700-9757 NR 9 TC 2 Z9 3 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 2000 VL 85 BP 280 EP 283 DI 10.1016/S0920-5632(00)00518-1 PG 4 WC Physics, Particles & Fields SC Physics GA 313UD UT WOS:000087016900044 ER PT J AU Kaminski, MD Nunez, L Purohit, A Lewandowski, M AF Kaminski, MD Nunez, L Purohit, A Lewandowski, M TI Metal surface decontamination using 1-hydroxyethane1,1-diphosphonic acid SO NUCLEAR TECHNOLOGY LA English DT Article DE chemical decontamination; diphosphonic acid; oxide dissolution ID OXIDES AB Substituted-ethane diphosphonic acids are art interesting moiety of organic acids because they display particularly favorable chemical characteristics toward the selective dissolution of metal oxides. In recent years, these systems have been studied to develop a cradle-to-grave process for the decontamination of ferrous metals typical of the nuclear power industry, This paper expands the understanding of this system to the dissolution of ferrous oxides found on corroded metals of nuclear facilities. It is found that pure iron oxides such as magnetite (Fe3O4) and hematite (Fe2O3) dissolved quickly (<1 h) using 0.5 M 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) and a strong reducing agent; the oxides with slower kinetics are the spinel structures, such as the nickel ferrites (NiOFe2O3), which dissolved very slowly in the foregoing solution, These results were confirmed in bench-scale tests on actual carbon steel and radioactively contaminated stainless steel samples. The decontamination of actual stainless steel from a nuclear reactor vessel required high concentrations of both HEDPA and reducing agent. Methods for treating the spent HEDPA solution are discussed. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Palisades Nucl Plant, Covert, MI 49043 USA. RP Kaminski, MD (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 18 TC 3 Z9 3 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAY PY 2000 VL 130 IS 2 BP 184 EP 195 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 305KV UT WOS:000086540000006 ER PT J AU Bayramian, AJ Bibeau, C Beach, RJ Marshall, CD Payne, SA Krupke, WF AF Bayramian, AJ Bibeau, C Beach, RJ Marshall, CD Payne, SA Krupke, WF TI Three-level Q-switched laser operation of ytterbium-doped Sr-5(PO4)(3)F at 985 nm SO OPTICS LETTERS LA English DT Article ID S-FAP LASER; YAG LASER; PERFORMANCE; CRYSTALS AB Ytterbium-doped Sr-5(PO4)(3)F was successfully lased at 985 nm in quasi-cw mode with a slope efficiency of 74% and an absorbed threshold energy of 18 mJ. Q-switched slope efficiencies of 21% were obtained with a maximum energy of 9.4 mJ in 8.8-ns pulses. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Bayramian, AJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 E Ave,L-482, Livermore, CA 94551 USA. NR 18 TC 12 Z9 12 U1 0 U2 2 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 MAY 1 PY 2000 VL 25 IS 9 BP 622 EP 624 DI 10.1364/OL.25.000622 PG 3 WC Optics SC Optics GA 307XU UT WOS:000086680100010 PM 18064130 ER PT J AU Arterburn, JB Rao, KV Goreham, DM Valenzuela, MV Holguin, MS Hall, KA Ott, KC Bryan, JC AF Arterburn, JB Rao, KV Goreham, DM Valenzuela, MV Holguin, MS Hall, KA Ott, KC Bryan, JC TI Functionalized rhenium(V) organoimido complexes as potential radiopharmaceuticals. 2. Synthesis, structural characterization, and reactivity of N-succinimidyl ester derivatives with amines SO ORGANOMETALLICS LA English DT Article ID RAY MOLECULAR-STRUCTURES; TC-99M LABELED BIOTIN; ORGANOMETALLIC COMPLEXES; MONOCLONAL-ANTIBODIES; TRANSITION-METALS; IMIDO COMPLEXES; HIGH-AFFINITY; PROTEINS; TECHNETIUM; CHEMISTRY AB Organoimidorhenium(V) complexes were synthesized as potential labeling agents for biologically relevant organic amines using the preconjugate approach. The bistriphenylphosphine organoimidorhenium N-succinimidyl ester complex Cl-3(PPh3)(2)Re=N-C6H4CO2N-(COCH2)(2) (2) was synthesized and characterized by single-crystal X-ray analysis. Complex 2 was coupled in aqueous dimethylformamide solvent with a series of primary and secondary amines, aminoacids, and a biotin-ethylenediamine derivative to give the corresponding amide complexes in good yields. These results demonstrate that the organoimido linkage is resistant toward hydrolysis and stable in the presence of more basic alkylamines. An unusual oxygen atom transfer reaction was observed between the byproduct N-hydroxysuccinimide and triphenylphosphine ligands when dichloromethane was used as solvent. The dithiocarbamate complexes Cl[Et2NCS2](2)Re=N-C6H4CO2N(COCH2)(2) (3) and O[(Et2NCS2)(2)Re=N-C6H4-CO2N(COCH2)(2)](2) (4) were also synthesized from 2. These complexes were unaffected by N-hydroxysuccinimide, but were not suitable for labeling due to hydrolysis of the organoimido groups under the reaction conditions. C1 New Mexico State Univ, Dept Chem & Biochem, Las Cruces, NM 88003 USA. Univ Calif Los Alamos Natl Lab, CST Div, Los Alamos, NM 87545 USA. Glaxo Wellcome Res & Dev Ltd, Med Res Ctr, Stevenage SG1 2NY, Herts, England. Symyx Technol Inc, Santa Clara, CA 95051 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Arterburn, JB (reprint author), New Mexico State Univ, Dept Chem & Biochem, MSC 3C,POB 30001, Las Cruces, NM 88003 USA. NR 53 TC 28 Z9 28 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD MAY 1 PY 2000 VL 19 IS 9 BP 1789 EP 1795 DI 10.1021/om990929w PG 7 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 310NZ UT WOS:000086835400025 ER PT J AU Zumkley, T Nakajima, H AF Zumkley, T Nakajima, H TI Solute diffusion of Ni in icosahedral Al-Pd-Mn quasicrystals SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID SINGLE QUASI-CRYSTALS; SELF-DIFFUSION; TEMPERATURE; MN-54; FE-59; NMR AB This paper presents the results of an experimental study of Ni solute diffusion in the single-grain icosahedral quasicrystalline compound Al70Pd21Mn9. Ni solute diffusion coefficients were measured over a temperature range from 699 to 1074 K. The radiotracer technique in combination with serial sectioning of the diffusion samples was used to determine concentration depth profiles. No deviation from Arrhenius behaviour was detected in the temperature range covered by the present experiments. The results are compared with the available diffusion data on quasicrystals and on diffusion in Al and various diffusion mechanisms proposed for quasicrystals are discussed. The most striking fact is that the diffusion of Ni and the diffusion of other transition-metal elements are found to be much slower than diffusion of non-transition-metal elements such as Ge and Zn in i-(Al-Pd-Mn) quasicrystalline alloys. Moreover, the activation enthalpies of diffusion of the transition-metal elements turned out to be considerably higher than those measured for the non-transition-metal elements. The present study shows that the diffusion of Ni atoms is Likely to proceed by a vacancy mechanism via Al and Pd sites. C1 Osaka Univ, Inst Sci & Ind Res, Osaka 5670047, Japan. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Zumkley, T (reprint author), Osaka Univ, Inst Sci & Ind Res, Mihogaoka 8-1, Osaka 5670047, Japan. NR 22 TC 15 Z9 15 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 2000 VL 80 IS 5 BP 1065 EP 1074 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 313QN UT WOS:000087010500004 ER PT J AU Rasmussen, T Vegge, T Leffers, T Pedersen, OB Jacobsen, KW AF Rasmussen, T Vegge, T Leffers, T Pedersen, OB Jacobsen, KW TI Simulation of structure and annihilation of screw dislocation dipoles SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID CROSS-SLIP; ATOMIC-STRUCTURE; METALS; ENERGETICS; COPPER AB Large scale atomistic simulations are used to investigate the properties of screw dislocation dipoles in copper. Spontaneous annihilation is observed for dipole heights less than 1 nm. Equilibrated dipoles of heights larger than 1 nm adopt a skew configuration due to the elastic anisotropy of Cu. The equilibrium splitting width of the screw dislocations decreases with decreasing dipole height, as expected from elasticity theory. The energy barriers, and corresponding transition states for annihilation of stable dipoles are determined for straight and for flexible dislocations for dipole heights up to 5.2 nm. In both cases the annihilation is initiated by cross-slip of one of the dislocations. For straight dislocations the activation energy shows a linear dependence on the inverse dipole height, and for flexible dislocations the dependence is roughly linear for the dipoles investigated. C1 Riso Natl Lab, Mat Res Dept, DK-400 Roskilde, Denmark. Tech Univ Denmark, Ctr Atom Scale Mat Phys, DK-2800 Lyngby, Denmark. Tech Univ Denmark, Dept Phys, DK-2800 Lyngby, Denmark. RP Rasmussen, T (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Jacobsen, Karsten/B-3602-2009; Vegge, Tejs/A-9419-2011 OI Jacobsen, Karsten/0000-0002-1121-2979; Vegge, Tejs/0000-0002-1484-0284 NR 27 TC 31 Z9 31 U1 0 U2 10 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 2000 VL 80 IS 5 BP 1273 EP 1290 PG 18 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 313QN UT WOS:000087010500019 ER PT J AU Rasmussen, T AF Rasmussen, T TI Comment on 'Atomistic simulation of cross-slip processes in model fcc structures' SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Editorial Material ID COPPER AB Recently Rao et al. (1999, Phil. Mag. A, 79, 1167) claimed reasonable agreement between their results for cross-slip activation energies (CSAEs) in Ni (from atomistic simulation) and in Cu (from scaling of the Ni result) and experimental results. Furthermore, the atomistic result for Cu by Rasmussen et al. (1997, Phys. Rev. B, 56, 2977) was described as deviating 'significantly' from theirs. This comment demonstrates that Rao et al.'s scaling approach is too simple and that it is possible to obtain good agreement between atomistic estimates of CSAEs with a more accurate, yet still approximate, scaling approach. It is noted that no experimentally derived value for the CSAE in Ni has been published. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Rasmussen, T (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 10 TC 4 Z9 4 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 2000 VL 80 IS 5 BP 1291 EP 1292 PG 2 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 313QN UT WOS:000087010500020 ER PT J AU Pieper, J Irrgang, KD Ratsep, M Voigt, J Renger, G Small, GJ AF Pieper, J Irrgang, KD Ratsep, M Voigt, J Renger, G Small, GJ TI Assignment of the lowest Q(y)-state and spectral dynamics of the CP29 chlorophyll a/b antenna complex of green plants: A hole-burning study SO PHOTOCHEMISTRY AND PHOTOBIOLOGY LA English DT Article ID LIGHT-HARVESTING-COMPLEX; EXCITATION-ENERGY TRANSFER; II SUBUNIT CP29; PHOTOSYSTEM-II; POLYACRYLAMIDE GELS; BINDING-PROTEINS; LHC-II; SPECTROSCOPY; SPINACH; DICYCLOHEXYLCARBODIIMIDE AB Low-temperature absorption, fluorescence and persistent nonphotochemical hole-burned spectra are reported for the CP29 chlorophyll (Chl) a/b antenna complex of photosystem II of green plants. The absorption-origin band of the lowest Q(y)-state lies at 678.2 nm and carries a width of similar to 130 cm(-1) that is dominated by inhomogeneous broadening at low temperatures. Its absorption intensity is equivalent to that of one of the six Chl a molecules of CP29. The absence of a significant satellite hole structure produced by hole burning, within the absorption band of the lowest state, indicates that the associated Chl a molecule is weakly coupled to the other Chl and, therefore, that the lowest-energy state is highly localized on a single Chl a molecule, The electron-phonon coupling of the 678.2 nn state is weak with a Huang-Rhys factor S of 0.5 and a peak phonon frequency to,) of similar to 20 cm(-1). These values give a Stokes shift (2S omega(m)) in good agreement with the measured positions of the absorption band at 678.2 mm and a fluorescence-origin band at 679.1 nm, Zero-phonon holes associated with the lowest state have a width of similar to 0.05 cm(-1) at 4.2 K, corresponding to a total effective dephasing time of similar to 400 ps, The temperature dependence of the zero-phonon holewidth indicates that this time constant is dominated at temperatures below 8 K by pure dephasing/spectral diffusion due to coupling of the optical transition to the glass-like two-level systems of the protein. Zero-phonon holewidths obtained for the Chl b bands at 638.5 and 650.0 nm, at 4.2 K, lead to lower limits of 900 +/- 150 fs and 4.2 +/- 0.3 ps, respectively, for the Chl b --> Chl a energy-transfer times, Downward energy transfer from the Chl a state(s) at 665.0 nm occurs in 5.3 +/- 0.6 ps at 4.2 K. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Humboldt Univ, Inst Phys, Berlin, Germany. Tech Univ Berlin, Max Volmer Inst Biophys Chem & Biochem, Berlin, Germany. RP Small, GJ (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. EM gsmall@iastate.edu NR 53 TC 36 Z9 36 U1 0 U2 6 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0031-8655 J9 PHOTOCHEM PHOTOBIOL JI Photochem. Photobiol. PD MAY PY 2000 VL 71 IS 5 BP 574 EP 581 DI 10.1562/0031-8655(2000)071<0574:AOTLQY>2.0.CO;2 PG 8 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 313FM UT WOS:000086989700011 PM 10818788 ER PT J AU Chumanov, G Picorel, R de Zarate, IO Cotton, TM Seibert, M AF Chumanov, G Picorel, R de Zarate, IO Cotton, TM Seibert, M TI Resonance raman and surface-enhanced resonance raman spectra of LH2 antenna complex from Rhodobacter sphaeroides and Ectothiorhodospira sp excited in the Q(x) and Q(y) transitions SO PHOTOCHEMISTRY AND PHOTOBIOLOGY LA English DT Article ID LIGHT-HARVESTING COMPLEX; PIGMENT-PROTEIN COMPLEX; SCATTERING SPECTROSCOPY; PHOTOSYNTHETIC MEMBRANES; RHODOPSEUDOMONAS-SPHAEROIDES; RHODOSPIRILLUM-RUBRUM; CRYSTAL-STRUCTURE; REACTION CENTERS; BACTERIAL; B800-850 AB Well-resolved vibrational spectra of LH2 complex isolated from two photosynthetic bacteria, Rhodobacter sphaeroides and Ectothiorhodospira sp,, were obtained using surface-enhanced resonance Raman scattering (SERRS) exciting into the Q(x) and the Q(y) transitions of bacteriochlorophyll a. High-quality SERRS spectra in the Q(y) region were accessible because the strong fluorescence background was quenched near the roughened Ag surface. A comparison of the spectra obtained with 590 nm and 752 mm excitation in the mid- and low-frequency regions revealed spectral differences between the two LH2 complexes as well as between the LH2 complexes and isolated bacteriochlorophyll a. Because peripheral modes of pigments contribute mainly to the low-frequency spectral region, frequencies and intensities of many vibrational bands in this region are affected by interactions with the protein. The results demonstrate that the microenvironment surrounding the pigments within the two LH2 complexes is somewhat different, despite the fact that the complexes exhibit similar electronic absorption spectra. These differences are most probably due to specific pigment-pigment and pigment-protein interactions within the LH2 complexes, and the approach might be useful for addressing subtle static and dynamic structural variances between pigment-protein complexes from different sources or in complexes altered chemically or genetically. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. CSIC, Estac Expt Aula Dei, Zaragoza, Spain. Iowa State Univ, Dept Chem, Ames, IA USA. RP Seibert, M (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI PICOREL, RAFAEL/K-7930-2014 OI PICOREL, RAFAEL/0000-0003-3791-129X FU NIGMS NIH HHS [GM48000] NR 34 TC 9 Z9 9 U1 0 U2 13 PU AMER SOC PHOTOBIOLOGY PI AUGUSTA PA BIOTECH PARK, 1021 15TH ST, SUITE 9, AUGUSTA, GA 30901-3158 USA SN 0031-8655 J9 PHOTOCHEM PHOTOBIOL JI Photochem. Photobiol. PD MAY PY 2000 VL 71 IS 5 BP 589 EP 595 DI 10.1562/0031-8655(2000)071<0589:RRASER>2.0.CO;2 PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 313FM UT WOS:000086989700013 PM 10818790 ER PT J AU West, GB AF West, GB TI Perturbation theory, asymptotic series and the renormalisation group SO PHYSICA A LA English DT Article DE asymptotic series; perturbation theory; QCD ID ANNIHILATION CROSS-SECTION; LOOP QCD CONTRIBUTION AB The divergence of the perturbation series in quantum field theory is reviewed and an argument presented showing that, at least in the unrenormalised theory, it must be asymptotic in the Poincare sense. Some basic concepts of asymptotic series are reviewed, By combining momentum analyticity with the constraints of the renormalisation group it is shown how in quantum chromodynamics the large order coefficients can be estimated and the effective expansion parameter for the series derived. The optimum number of meaningful terms in the series is estimated. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP West, GB (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS B285, Los Alamos, NM 87545 USA. NR 9 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD MAY 1 PY 2000 VL 279 IS 1-4 BP 180 EP 187 DI 10.1016/S0378-4371(99)00531-2 PG 8 WC Physics, Multidisciplinary SC Physics GA 310JR UT WOS:000086823200016 ER PT J AU Kalos, MH Pederiva, F AF Kalos, MH Pederiva, F TI Fermion Monte Carlo for continuum systems SO PHYSICA A LA English DT Article DE quantum Monte Carlo; fermion systems; He-3 ID HELIUM AB We have been studying methods for the Monte Carlo treatment of many-fermion systems in continuous space. We use generalizations of diffusion Monte Carlo that involve ensembles of correlated pairs of random walkers that carry opposite signs. We have been able to exhibit stable long-term behavior of the random walks: the new method suppresses the usual decay of the signal-to-noise ratio of the integrals that appear in a quotient that estimates the energy. One way of checking this result is to calculate a bosonic system with the same Hamiltonian and to estimate separately the boson-fermion energy difference. Specifically, we performed a "fixed-node" calculation of 14 He-3 atoms, and then a "transient estimation" removing the fixed-node constraint. The rate of decay in imaginary time of the energy denominator gives a fairly accurate measure of the boson-fermion energy difference, in good agreement with the exact energy difference. This suggests a simple method of estimating fermion energies, viz., to use directly the bosonic energy and the energy difference measured in a transient calculation. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Trento, Dipartimento Fis, I-38050 Povo Trento, Italy. RP Kalos, MH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 8 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD MAY 1 PY 2000 VL 279 IS 1-4 BP 236 EP 243 DI 10.1016/S0378-4371(00)00009-1 PG 8 WC Physics, Multidisciplinary SC Physics GA 310JR UT WOS:000086823200022 ER PT J AU Graf, MJ Yip, SK Sauls, JA AF Graf, MJ Yip, SK Sauls, JA TI Transport in the heavy-fermion superconductor UPt3 SO PHYSICA B LA English DT Article; Proceedings Paper CT 22nd International Conference on Low Temperature Physics CY AUG 04-11, 1999 CL HELSINKI UNIV TECHNOL, HELSINKI, FINLAND SP Commiss C5 low Temp Phys, Int Union Pure & Appl Phys, Acad Finland, Helsinki Univ Technol, Int Assoc Promot Sci, Oxford Instruments Ltd, FortumCorp, Nokia Grp, Finnair Ltd, Datex Engstrom Ltd, Finnish Phys Soc, Picker Nordstar Ltd, Neuromag ltd, SAP Finland Ltd, Espoo Elect Ltd, Outokumpu Ltd, City Espoo, Finnish Acad Sci & Letters, DCA-Instruments Ltd, Vaisala Ltd HO HELSINKI UNIV TECHNOL DE heavy fermions; sound attenuation; thermal conductivity; unconventional superconductivity; UPt3 ID THERMAL-CONDUCTIVITY; ORDER-PARAMETER; GAP STRUCTURE; PHASES AB We report new theoretical results and analysis for the transport properties of superconducting UPt3 based on the leading models for the pairing symmetry. We use Fermi surface data and the measured inelastic scattering rate to show that the low-temperature thermal conductivity and transverse sound attenuation in the A- and B-phase of UPt3 are in excellent agreement with pairing states belonging to the two-dimensional orbital El, representation. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. Natl Ctr Theoret Sci, Div Phys, Hsinchu 300, Taiwan. Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. RP Graf, MJ (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RI Yip, Sungkit/F-3422-2015; OI Sauls, James/0000-0002-3619-2572 NR 11 TC 5 Z9 5 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 MAY PY 2000 VL 280 IS 1-4 BP 176 EP 177 DI 10.1016/S0921-4526(99)01557-4 PG 2 WC Physics, Condensed Matter SC Physics GA 301WP UT WOS:000086333700047 ER PT J AU Morr, DK AF Morr, DK TI The resonance peak in the high-T-c cuprates SO PHYSICA B LA English DT Article; Proceedings Paper CT 22nd International Conference on Low Temperature Physics CY AUG 04-11, 1999 CL HELSINKI UNIV TECHNOL, HELSINKI, FINLAND SP Commiss C5 low Temp Phys, Int Union Pure & Appl Phys, Acad Finland, Helsinki Univ Technol, Int Assoc Promot Sci, Oxford Instruments Ltd, FortumCorp, Nokia Grp, Finnair Ltd, Datex Engstrom Ltd, Finnish Phys Soc, Picker Nordstar Ltd, Neuromag ltd, SAP Finland Ltd, Espoo Elect Ltd, Outokumpu Ltd, City Espoo, Finnish Acad Sci & Letters, DCA-Instruments Ltd, Vaisala Ltd HO HELSINKI UNIV TECHNOL DE magnetic excitations; resonance peak; spin-fermion model ID NEUTRON-SCATTERING; EXCITATIONS; YBA2CU3O6+X AB I present a theory in which the resonance peak observed in inelastic neutron scattering experiments on YBa2Cu3O6+x and Bi2Sr2CaCu2O8+x. arises from a dispersing spin mode. I argue that it is heavily damped in the normal state and becomes visible in the superconducting state due to a drastic decrease in the spin damping. I show thar a spin-fermion model correctly describes the doping dependence of the peak position and of its integrated intensity. Finally, I derive a criterion for the existence of the resonance peak in other cuprate superconductors. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Morr, DK (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Mail Stop B262, Los Alamos, NM 87545 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 2000 VL 280 IS 1-4 BP 178 EP 179 DI 10.1016/S0921-4526(99)01559-8 PG 2 WC Physics, Condensed Matter SC Physics GA 301WP UT WOS:000086333700048 ER PT J AU Endoh, Y Birgeneau, RJ Kastner, MA Shirane, G Yamada, K AF Endoh, Y Birgeneau, RJ Kastner, MA Shirane, G Yamada, K TI Static and dynamical magnetic characters in doped Cu oxides SO PHYSICA B LA English DT Article; Proceedings Paper CT 22nd International Conference on Low Temperature Physics CY AUG 04-11, 1999 CL HELSINKI UNIV TECHNOL, HELSINKI, FINLAND SP Commiss C5 low Temp Phys, Int Union Pure & Appl Phys, Acad Finland, Helsinki Univ Technol, Int Assoc Promot Sci, Oxford Instruments Ltd, FortumCorp, Nokia Grp, Finnair Ltd, Datex Engstrom Ltd, Finnish Phys Soc, Picker Nordstar Ltd, Neuromag ltd, SAP Finland Ltd, Espoo Elect Ltd, Outokumpu Ltd, City Espoo, Finnish Acad Sci & Letters, DCA-Instruments Ltd, Vaisala Ltd HO HELSINKI UNIV TECHNOL DE ac susceptibility; diagonal spin stripe; vertical spin stripe ID SPIN CORRELATIONS; LA2-XSRXCUO4; LA2CUO4; HOLES; PURE AB The discovery of the spin density wave (SDW) state defined as stripe in the doped Cu oxides becomes a central issue in the elucidation of the high-temperature superconducting mechanism. We present the coexistence of the stripe order and superconductivity, and the change of the stripe structure associated with the insulter-metal transition. Both static and dynamical SDW are robust of the high-temperature superconducting Cu oxides. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Tohoku Univ, CREST, Dept Phys, Aoba Ku, Sendai, Miyagi 9808578, Japan. MIT, Dept Phys, Cambridge, MA 02139 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Kyoto Univ, Inst Chem Res, Kyoto 6110011, Japan. RP Endoh, Y (reprint author), Tohoku Univ, CREST, Dept Phys, Aoba Ku, Aramaki Aza Aoba, Sendai, Miyagi 9808578, Japan. RI Yamada, Kazuyoshi/C-2728-2009 NR 21 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 2000 VL 280 IS 1-4 BP 201 EP 204 DI 10.1016/S0921-4526(99)01573-2 PG 4 WC Physics, Condensed Matter SC Physics GA 301WP UT WOS:000086333700055 ER PT J AU Corson, J Orenstein, J Eckstein, JN Bozovic, I AF Corson, J Orenstein, J Eckstein, JN Bozovic, I TI Low-temperature AC conductivity of Bi2Sr2CaCu2O8+delta SO PHYSICA B LA English DT Article; Proceedings Paper CT 22nd International Conference on Low Temperature Physics CY AUG 04-11, 1999 CL HELSINKI UNIV TECHNOL, HELSINKI, FINLAND SP Commiss C5 low Temp Phys, Int Union Pure & Appl Phys, Acad Finland, Helsinki Univ Technol, Int Assoc Promot Sci, Oxford Instruments Ltd, FortumCorp, Nokia Grp, Finnair Ltd, Datex Engstrom Ltd, Finnish Phys Soc, Picker Nordstar Ltd, Neuromag ltd, SAP Finland Ltd, Espoo Elect Ltd, Outokumpu Ltd, City Espoo, Finnish Acad Sci & Letters, DCA-Instruments Ltd, Vaisala Ltd HO HELSINKI UNIV TECHNOL DE Bi-2212; Terahertz radiation AB We report measurements of anamolously large dissipative conductivities, sigma(1), in Bi2Sr2 CaCu2 O8+delta at low temperatures. We have measured the complex conductivity of Bi2Sr2 CaCu2 O8+delta thin films at 100-600 GHz as a function of doping from the underdoped to the overdoped state. At low temperatures there exists a residual al which scales with the T = 0 superfluid density as the doping is varied. This residual ar is larger than the possible contribution to sigma(1) from a thermal population of quasiparticles (QP) at the d-wave gap nodes, (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Dept Phys, Berkeley, CA 94720 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Oxxel GmbH, D-28359 Bremen, Germany. RP Corson, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Dept Phys, Berkeley, CA 94720 USA. RI Orenstein, Joseph/I-3451-2015 NR 6 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 MAY PY 2000 VL 280 IS 1-4 BP 212 EP 213 DI 10.1016/S0921-4526(99)01580-X PG 2 WC Physics, Condensed Matter SC Physics GA 301WP UT WOS:000086333700058 ER PT J AU Liu, X Pohl, RO Crandall, RS AF Liu, X Pohl, RO Crandall, RS TI Lattice vibration of amorphous and disordered crystalline silicon SO PHYSICA B LA English DT Article; Proceedings Paper CT 22nd International Conference on Low Temperature Physics CY AUG 04-11, 1999 CL HELSINKI UNIV TECHNOL, HELSINKI, FINLAND SP Commiss C5 low Temp Phys, Int Union Pure & Appl Phys, Acad Finland, Helsinki Univ Technol, Int Assoc Promot Sci, Oxford Instruments Ltd, FortumCorp, Nokia Grp, Finnair Ltd, Datex Engstrom Ltd, Finnish Phys Soc, Picker Nordstar Ltd, Neuromag ltd, SAP Finland Ltd, Espoo Elect Ltd, Outokumpu Ltd, City Espoo, Finnish Acad Sci & Letters, DCA-Instruments Ltd, Vaisala Ltd HO HELSINKI UNIV TECHNOL DE amorphous silicon; internal friction; low-energy tunneling states ID LOW-ENERGY EXCITATIONS AB The disappearance of low-energy tunneling states in an amorphous solid discovered recently has shown that the amorphous structure is not their primary cause, as had previously been widely accepted. We have also found that the same tunneling states can be generated in crystalline silicon as the crystal structure is gradually disordered by Si+ and B+ ion implantation. Most strikingly, their number densities saturate at their characteristic level regardless whether the crystal amorphizes or not. It is concluded that the nature of the tunneling states, and the cause for their saturation density, should be explored in disordered crystals. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Cornell Univ, Atom & Solid State Phys Lab, Ithaca, NY 14853 USA. SFA Inc, Largo, MD 20774 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Liu, X (reprint author), Cornell Univ, Atom & Solid State Phys Lab, Ithaca, NY 14853 USA. NR 5 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 2000 VL 280 IS 1-4 BP 251 EP 252 DI 10.1016/S0921-4526(99)01664-6 PG 2 WC Physics, Condensed Matter SC Physics GA 301WP UT WOS:000086333700072 ER PT J AU Bud'ko, SL Canfield, PC AF Bud'ko, SL Canfield, PC TI Superconductivity in presence of localized magnetic moments. Case study of Er(Ni,Co)(2)B2C SO PHYSICA B LA English DT Article; Proceedings Paper CT 22nd International Conference on Low Temperature Physics CY AUG 04-11, 1999 CL HELSINKI UNIV TECHNOL, HELSINKI, FINLAND SP Commiss C5 low Temp Phys, Int Union Pure & Appl Phys, Acad Finland, Helsinki Univ Technol, Int Assoc Promot Sci, Oxford Instruments Ltd, FortumCorp, Nokia Grp, Finnair Ltd, Datex Engstrom Ltd, Finnish Phys Soc, Picker Nordstar Ltd, Neuromag ltd, SAP Finland Ltd, Espoo Elect Ltd, Outokumpu Ltd, City Espoo, Finnish Acad Sci & Letters, DCA-Instruments Ltd, Vaisala Ltd HO HELSINKI UNIV TECHNOL DE borocarbides; H-T phase diagram; superzone gap; weak ferromagnetism ID ORDERING TEMPERATURES; ERNI2B2C; COEXISTENCE; CO; TM; ER AB Some recent results of magnetic and transport measurements on single crystals of the Er(Ni,Co)(2)B2C series will be presented and discussed, in particular, possible evidence of a superzone gap formation at the antiferromagnetic phase transition in pure ErNi2B2C, detailed anisotropic H-T phase diagrams and their modification with Co doping, and enhancement of the superconducting critical current in the weak ferromagnetic phase. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Bud'ko, SL (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Canfield, Paul/H-2698-2014 NR 20 TC 8 Z9 8 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 MAY PY 2000 VL 280 IS 1-4 BP 356 EP 361 DI 10.1016/S0921-4526(99)01742-1 PG 6 WC Physics, Condensed Matter SC Physics GA 301WP UT WOS:000086333700100 ER PT J AU Palmieri, VG Abreu, MC Bell, WH Berglund, P de Boer, W Borchi, E Borer, K Bruzzi, M Buontempo, S Casagrande, L Chapuy, S Cindro, V D'Ambrosio, N Da Via, C Devine, S Dezillie, B Dimcovski, Z Eremin, V Esposito, A Granata, V Grigoriev, E Hauler, F Heijne, E Heising, S Janos, S Jungermann, L Konorov, I Li, Z Lourenco, C Mikuz, M Niinikoski, TO O'Shea, V Pagano, S Paul, S Pirollo, S Pretzl, K Rato, P Ruggiero, G Smith, K Sonderegger, P Sousa, P Verbitskaya, E Watts, S Zavrtanik, M AF Palmieri, VG Abreu, MC Bell, WH Berglund, P de Boer, W Borchi, E Borer, K Bruzzi, M Buontempo, S Casagrande, L Chapuy, S Cindro, V D'Ambrosio, N Da Via, C Devine, S Dezillie, B Dimcovski, Z Eremin, V Esposito, A Granata, V Grigoriev, E Hauler, F Heijne, E Heising, S Janos, S Jungermann, L Konorov, I Li, Z Lourenco, C Mikuz, M Niinikoski, TO O'Shea, V Pagano, S Paul, S Pirollo, S Pretzl, K Rato, P Ruggiero, G Smith, K Sonderegger, P Sousa, P Verbitskaya, E Watts, S Zavrtanik, M CA RD39 Collaboration TI Radiation hard position-sensitive cryogenic silicon detectors: the Lazarus effect SO PHYSICA B LA English DT Article; Proceedings Paper CT 22nd International Conference on Low Temperature Physics CY AUG 04-11, 1999 CL HELSINKI UNIV TECHNOL, HELSINKI, FINLAND SP Commiss C5 low Temp Phys, Int Union Pure & Appl Phys, Acad Finland, Helsinki Univ Technol, Int Assoc Promot Sci, Oxford Instruments Ltd, FortumCorp, Nokia Grp, Finnair Ltd, Datex Engstrom Ltd, Finnish Phys Soc, Picker Nordstar Ltd, Neuromag ltd, SAP Finland Ltd, Espoo Elect Ltd, Outokumpu Ltd, City Espoo, Finnish Acad Sci & Letters, DCA-Instruments Ltd, Vaisala Ltd HO HELSINKI UNIV TECHNOL DE irradiated silicon detectors; cryogenic detectors; Lazarus effect AB The discovery of the so-called Lazarus effect, namely the recovery of the charge collection efficiency (CCE) of irradiated silicon detectors by means of cryogenic cooling has entailed an increasing interest in the behavior of silicon detectors at cryogenic temperatures. We have measured the CCE of a silicon p-i-n diode detector previously irradiated with an equivalent fluence of 1 x 10(15) n/cm(2) neutrons of 1 MeV energy. The charge collection efficiency has been measured at 77 ii;. showing that the low-temperature operation considerably decreases the bias current. This is also the case when forward voltage bias is applied, which then becomes a suitable option. In this condition, the sample shows a charge collection efficiency in excess of 65% at 250 V corresponding to a most probable signal for a minimum ionizing particle of 21000e(-). (C) 2000 Elsevier Science B.V. All rights reserved. C1 CERN, Div EP, CH-1211 Geneva 23, Switzerland. LIP, P-1000 Lisbon, Portugal. Univ Glasgow, Glasgow, Lanark, Scotland. Helsinki Univ Technol, FIN-02150 Espoo, Finland. Univ Karlsruhe, IEKP, Karlsruhe, Germany. Ist Nazl Fis Nucl, I-50125 Florence, Italy. Univ Florence, Florence, Italy. Univ Bern, LHEP, Bern, Switzerland. Ist Nazl Fis Nucl, I-80125 Naples, Italy. Univ Naples, Naples, Italy. Univ Geneva, Dept Radiol, Geneva, Switzerland. JSI, Ljubljana, Slovenia. Univ Ljubljana, Ljubljana, Slovenia. Brunel Univ, Brunel, England. Brookhaven Natl Lab, Upton, NY 11973 USA. IOFFE, St Petersburg, Russia. Tech Univ Munich, D-8000 Munich, Germany. RP Palmieri, VG (reprint author), CERN, Div EP, CH-1211 Geneva 23, Switzerland. RI Zavrtanik, Marko/A-1524-2008; Rato Mendes, Pedro/F-8827-2010; O'Shea, Val/G-1279-2010; Verbitskaya, Elena/D-1521-2014; Bruzzi, Mara/K-1326-2015; Pagano, Sergio/C-5332-2008; OI Zavrtanik, Marko/0000-0001-5606-6912; Rato Mendes, Pedro/0000-0001-9929-0869; D'Ambrosio, Nicola/0000-0001-9849-8756; O'Shea, Val/0000-0001-7183-1205; Bruzzi, Mara/0000-0001-7344-8365; Pagano, Sergio/0000-0001-6894-791X; Abreu, Maria Conceicao/0000-0003-0093-7496 NR 6 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 MAY PY 2000 VL 280 IS 1-4 BP 532 EP 534 DI 10.1016/S0921-4526(99)01853-0 PG 3 WC Physics, Condensed Matter SC Physics GA 301WP UT WOS:000086333700151 ER PT J AU Jaime, M Movshovich, R Sarrao, J Stewart, G Kim, J Canfield, PC AF Jaime, M Movshovich, R Sarrao, J Stewart, G Kim, J Canfield, PC TI Heat capacity measured up to 60 T in Ce3Bi4Pt3 Kondo insulator SO PHYSICA B LA English DT Article; Proceedings Paper CT 22nd International Conference on Low Temperature Physics CY AUG 04-11, 1999 CL HELSINKI UNIV TECHNOL, HELSINKI, FINLAND SP Commiss C5 low Temp Phys, Int Union Pure & Appl Phys, Acad Finland, Helsinki Univ Technol, Int Assoc Promot Sci, Oxford Instruments Ltd, FortumCorp, Nokia Grp, Finnair Ltd, Datex Engstrom Ltd, Finnish Phys Soc, Picker Nordstar Ltd, Neuromag ltd, SAP Finland Ltd, Espoo Elect Ltd, Outokumpu Ltd, City Espoo, Finnish Acad Sci & Letters, DCA-Instruments Ltd, Vaisala Ltd HO HELSINKI UNIV TECHNOL DE specific heat; Kondo effect; heavy fermions; pulsed magnetic fields ID MAGNETIC-FIELDS; GAP AB The low-temperature heat capacity C(T) of the Kondo insulator Ce3Bi4Pt3 has been measured in the new 60 T long pulse magnet at NHMFL-LANL. A large increase in the zero temperature Sommerfeld coefficient gamma = (C/T)(T-->0) is observed in a magnetic field of 40 T. The high magnetic field value gamma(40T) = 47 mJ/mol K-2 is consistent with a magnetic field induced Kondo insulator to heavy fermion metal phase transition, observed for the first time with a thermodynamic probe. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Florida, Gainesville, FL 32611 USA. Iowa State Univ, Ames, IA 50011 USA. RP Jaime, M (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Canfield, Paul/H-2698-2014; Jaime, Marcelo/F-3791-2015 OI Jaime, Marcelo/0000-0001-5360-5220 NR 4 TC 2 Z9 2 U1 1 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 MAY PY 2000 VL 280 IS 1-4 BP 563 EP 564 DI 10.1016/S0921-4526(99)01866-9 PG 2 WC Physics, Condensed Matter SC Physics GA 301WP UT WOS:000086333700164 ER PT J AU Kopnin, NB AF Kopnin, NB TI The vortex physics which comes from the vortex core SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 22nd International Conference on Low Temperature Physics CY AUG 04-11, 1999 CL HELSINKI UNIV TECHNOL, HELSINKI, FINLAND SP Commiss C5 low Temp Phys, Int Union Pure & Appl Phys, Acad Finland, Helsinki Univ Technol, Int Assoc Promot Sci, Oxford Instruments Ltd, FortumCorp, Nokia Grp, Finnair Ltd, Datex Engstrom Ltd, Finnish Phys Soc, Picker Nordstar Ltd, Neuromag ltd, SAP Finland Ltd, Espoo Elect Ltd, Outokumpu Ltd, City Espoo, Finnish Acad Sci & Letters, DCA-Instruments Ltd, Vaisala Ltd HO HELSINKI UNIV TECHNOL DE flux flow; Hall effect; vortex mass ID D-WAVE SUPERCONDUCTORS; SPECTRAL FLOW; MUTUAL FRICTION; FLUX-FLOW; DYNAMICS; STATES; MASS AB A theoretical view of vortex core states and of their effects on physics of vortices in clean s- and d-wave-type II superconductors is presented based on a semi-classical picture of a vortex core as an Andreev potential well containing many quasiparticle states. We discuss the density of states, the vortex dissipation, Hall effect, and the vortex mass. The dynamic characteristics are determined by relaxation of core excitations driven by a moving vortex. In a d-wave superconductor, gap nodes make the con states more extended and introduce novel features into thermodynamics and kinetics of vortices. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, LD Landau Theoret Phys Inst, Moscow 117940, Russia. Argonne Natl Lab, Argonne, IL 60439 USA. RP Kopnin, NB (reprint author), Russian Acad Sci, LD Landau Theoret Phys Inst, Kosygin Str 2, Moscow 117940, Russia. EM kopnin@landau.ac.ru NR 15 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD MAY PY 2000 VL 280 IS 1-4 BP 231 EP 236 DI 10.1016/S0921-4526(99)01635-X PG 6 WC Physics, Condensed Matter SC Physics GA 301WP UT WOS:000086333700064 ER PT J AU Reichhardt, C Scalettar, RT Zimanyi, GT Gronbech-Jensen, N AF Reichhardt, C Scalettar, RT Zimanyi, GT Gronbech-Jensen, N TI Shapiro steps in driven vortex lattices interacting with periodic pinning arrays SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Vortex Matter in Superconductors at Extreme Scales and Conditions CY SEP 18-24, 1999 CL IRAKLION, GREECE SP VORTEX, ESF DE Shapiro steps; vortex; vortex lattices; flux pinning; pinning arrays ID ANTIDOT LATTICE; LOGARITHMIC INTERACTIONS; REGULAR ARRAY; MAGNETIC DOTS; THIN-FILMS; VORTICES; SUPERCONDUCTORS; SUMMATION; PHASES; MEDIA AB We examine the effects of DC and AC driving on vortex lattices in periodic pinning arrays for a system containing twice as many vortices as pinning sites. The vortex flow occurs by the motion of the interstitial vortices through a periodic potential generated by the vortices that remain pinned at the pinning sites. With an AC offset, we observe Shapiro steps when the interstitial vortex motion interferes with the applied AC driving. The widths of the Shapiro steps as a function of the magnitude of the AC driving are found to follow a Bessel function in agreement with theory. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. RP Reichhardt, C (reprint author), Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. NR 24 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY PY 2000 VL 332 IS 1-4 BP 1 EP 4 DI 10.1016/S0921-4534(99)00635-8 PG 4 WC Physics, Applied SC Physics GA 317UK UT WOS:000087245200003 ER PT J AU Aranson, IS Vinokur, VM Kopnin, NB AF Aranson, IS Vinokur, VM Kopnin, NB TI Nucleation of vortices in superfluid He-3-B by thermal quench SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Vortex Matter in Superconductors at Extreme Scales and Conditions CY SEP 18-24, 1999 CL IRAKLION, GREECE SP VORTEX, ESF DE nucleation; vortices; Ginzburg-Landau model; front instability; thermal quench ID TRANSITION AB We show that nucleation of vortex loops in superfluid He-3 by rapid thermal quench in the presence of superflow is dominated by a transverse instability of the moving normal-superfluid interface. Exact expressions for the instability threshold as a function of supercurrent density and the front velocity are found. The results are verified by numerical solution of the Ginzburg-Landau equation. (C) 2000 Elsevier Science B.V. C1 Argonne Natl Lab, Argonne, IL 60439 USA. LD Landau Theoret Phys Inst, Moscow 117334, Russia. RP Aranson, IS (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Aranson, Igor/I-4060-2013 NR 5 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY PY 2000 VL 332 IS 1-4 BP 129 EP 130 DI 10.1016/S0921-4534(99)00654-1 PG 2 WC Physics, Applied SC Physics GA 317UK UT WOS:000087245200023 ER PT J AU Jung, J Yan, H Darhmaoui, H Kwok, WK AF Jung, J Yan, H Darhmaoui, H Kwok, WK TI Fast vortex motion and filamentary phase separation in YBCO and TlBCCO thin films SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Vortex Matter in Superconductors at Extreme Scales and Conditions CY SEP 18-24, 1999 CL IRAKLION, GREECE SP VORTEX, ESF DE critical current density; flux pinning; flux dynamics; thin films ID HIGH-TEMPERATURE SUPERCONDUCTORS; CRITICAL-CURRENT-DENSITY; MAGNETIC-RELAXATION; YBA2CU3O7-DELTA; BEHAVIOR; DEFECTS; CREEP AB We found a correlation between the temperature dependence of the normalized magnetic relaxation rate S(T) = d In J/d In t, and the filamentary phase separation in the a-b planes of high T-c thin films, i.e., the ratio of the amount of an underdoped phase to that of an optimally doped one. These phases are characterized by different temperature dependences of the critical current density J(c)(T). J(c)(T) of the underdoped component is that of the Ginzburg-Landau (CL) one [with J(c)(T) proportional to (T-c - T)(3/2)]. For the phase closer to the optimum doping, J(c)(T) is described by the Ambegaokar-Baratoff (AB) behaviour at low temperatures with a crossover to the GL one above 0.8T(c), which is indicative of the presence of the Josephson nanostructures in the a-b planes. The results revealed that when the amount of the underdoped GL-like phase increases above a certain threshold value, a peak appears in S(T) at a temperature of 20-30 K and its height gradually increases with the magnitude of the critical current flowing through this phase. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Alakhawayn Univ, Sch Sci & Engn, Waltair 530003, Andhra Pradesh, India. RP Jung, J (reprint author), Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. NR 15 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY PY 2000 VL 332 IS 1-4 BP 207 EP 213 DI 10.1016/S0921-4534(99)00673-5 PG 7 WC Physics, Applied SC Physics GA 317UK UT WOS:000087245200037 ER PT J AU Mota, AC Dumont, E Smith, JL Maeno, Y AF Mota, AC Dumont, E Smith, JL Maeno, Y TI Unconventional strong pinning in multiphase superconductors SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Vortex Matter in Superconductors at Extreme Scales and Conditions CY SEP 18-24, 1999 CL IRAKLION, GREECE SP VORTEX, ESF DE pinning structures; magnetic relaxation; flux creep; flux pinning ID MUON-SPIN RELAXATION; U1-XTHXBE13; STATE; UPT3 AB Upt(3) and thoriated UBe13 are the only known examples of superconductors that show more thin one superconducting phase below T-c. In both materials, a second jump in the specific heat is clearly observed at a temperature T-c2 < T-c. By means of magnetic relaxation measurements in UPt3 and thoriated UBe13. we found vortex creep transitions of about three orders of magnitude at T-c2, From a regime of thermally activated creep to a low temperature regime of no creep in a time scale of 10(5) s. This lack of creep points to new type of extremely strong pinning structures and new type of vortices in the low temperature superconducting phases of these unconventional superconductors. Recently. we detected similar vortex transition in Sr5RuO4 at T approximate to 30 mK. (C) 2000 Elsevier Science B.V. All rights reserved. C1 ETH Honggerberg, Festkorperphys Lab, CH-8093 Zurich, Switzerland. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Kyoto Univ, Dept Phys, Kyoto 60601, Japan. RP Mota, AC (reprint author), ETH Honggerberg, Festkorperphys Lab, CH-8093 Zurich, Switzerland. NR 13 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY PY 2000 VL 332 IS 1-4 BP 272 EP 276 DI 10.1016/S0921-4534(99)00684-X PG 5 WC Physics, Applied SC Physics GA 317UK UT WOS:000087245200048 ER PT J AU Eskildsen, MR Fisher, IR Gammel, PL Bishop, DJ Andersen, NH Mortensen, K Canfield, PC AF Eskildsen, MR Fisher, IR Gammel, PL Bishop, DJ Andersen, NH Mortensen, K Canfield, PC TI Non-locality and the flux line lattice square to hexagonal symmetry transition in the borocarbide superconductors SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Vortex Matter in Superconductors at Extreme Scales and Conditions CY SEP 18-24, 1999 CL IRAKLION, GREECE SP VORTEX, ESF DE flux line lattice; borocarbides; non-locality ID NEUTRON-SCATTERING; LUNI2B2C; ERNI2B2C; YNI2B2C; STATE; NI; LU(NI1-XCOX)(2)B2C; SUSCEPTIBILITY; RESISTIVITY; MAGNETISM AB Using small angle neutron scattering we have studied the square to hexagonal flux line lattice symmetry transition in different members of the borocarbide superconductors. The studies were performed using samples of ErNi2B2C, Lu(Ni1-xCox)(2)B2C with cobalt doping levels x = 1.5-9% and Y0.64Lu0.36Ni2B2C. We find that the onset field of the symmetry transition can be shifted more than an order of magnitude due to changes in the range of the non-local electrodynamics. Comparing the results to transport measurements of the electronic mean free path and the superconducting coherence length we find that the transition onset follows a model by V. Kogan et nl., which includes non-local corrections to the London model due to the Fermi surface anisotropy of the borocarbides. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Riso Natl Lab, DK-4000 Roskilde, Denmark. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Eskildsen, MR (reprint author), Univ Geneva, Dept Phys Mat Condensee, 24 Quai E Ansermet, CH-1211 Geneva 4, Switzerland. RI Mortensen, Kell/A-5066-2009; Eskildsen, Morten/E-7779-2011; Andersen, Niels/A-3872-2012; Canfield, Paul/H-2698-2014 OI Mortensen, Kell/0000-0002-8998-9390; NR 28 TC 3 Z9 3 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY PY 2000 VL 332 IS 1-4 BP 320 EP 326 DI 10.1016/S0921-4534(99)00694-2 PG 7 WC Physics, Applied SC Physics GA 317UK UT WOS:000087245200058 ER PT J AU Balatsky, AV AF Balatsky, AV TI Field-induced d(x2-y2)+id(xy) state and marginal stability of high-T-c superconductor SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Vortex Matter in Superconductors at Extreme Scales and Conditions CY SEP 18-24, 1999 CL IRAKLION, GREECE SP VORTEX, ESF DE field-induced d(x2-y2) + id(xy) state; marginal stability; d-wave superconductor ID D-WAVE SUPERCONDUCTORS; T-C SUPERCONDUCTORS; SYMMETRY ORDER PARAMETERS; SPONTANEOUS TIME-REVERSAL; THERMAL-CONDUCTIVITY; D(X(2)-Y(2))-WAVE SUPERCONDUCTOR; MAGNETIC-IMPURITIES; PAIRING SYMMETRY; PARITY BREAKING; SURFACE AB It is shown that the complex d(xy) component is generated in d-wave superconductor in the magnetic field. As one enters superconducting state at finite field, the normal to superconducting transition occurs into bulk d(x2-y2) + id(xy) (d + id') state. The driving force for the transition is the linear coupling between magnetic field and non-zero magnetization of the d + id' condensate. The external magnetic field violates parity and time reversal symmetries and the nodal quasiparticle states respond by generating the id(xy) component of the order parameter, with the magnitude estimated to be on the order of a few Kelvins. Parity (P) and time reversal (T) symmetries are violated in this state. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, T Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, MST Div, Los Alamos, NM 87545 USA. RP Balatsky, AV (reprint author), Univ Calif Los Alamos Natl Lab, T Div, B262, Los Alamos, NM 87545 USA. NR 34 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY PY 2000 VL 332 IS 1-4 BP 337 EP 342 DI 10.1016/S0921-4534(99)00697-8 PG 6 WC Physics, Applied SC Physics GA 317UK UT WOS:000087245200061 ER PT J AU Hucho, C Carter, JM Muller, V Petrean, A Kwok, WK AF Hucho, C Carter, JM Muller, V Petrean, A Kwok, WK TI Reentrant softening as precursor to reentrant melting of the vortex lattice in YBCO single crystal SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Vortex Matter in Superconductors at Extreme Scales and Conditions CY SEP 18-24, 1999 CL IRAKLION, GREECE SP VORTEX, ESF DE softening; melting; vortex lattice ID SUPERCONDUCTORS AB A vibrating sample technique was used to study the elastic behavior of the magnetic vortex system in YBa2Cu3O7 single crystals. The setup consists of a system of two weakly coupled mechanical oscillators (transducer, sample), the frequency and Q of which depend sensitively on the frequencies of the two subsystems as well as the coupling between both. By sweeping a magnetic field at temperatures below the superconducting transition temperature T-c, we observe pronounced attenuation peaks at characteristic field strengths H-1 and H-2. These fields mark points of constant elasticity of the vortex ensemble. Since softening precedes the melting of the vortex lattice by approaching H-c1 as well as H-c2, the observed angular dependence of H-1 and H-2 is interpreted as due to reentrant softening as precursor to reentrant melting. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Paul Drude Inst Festkorperelekt, D-10117 Berlin, Germany. Univ Augsburg, Inst Expt Phys 3, D-86135 Augsburg, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. RP Hucho, C (reprint author), Paul Drude Inst Festkorperelekt, Hausvogteipl 5-7, D-10117 Berlin, Germany. NR 12 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY PY 2000 VL 332 IS 1-4 BP 370 EP 373 DI 10.1016/S0921-4534(99)00705-4 PG 4 WC Physics, Applied SC Physics GA 317UK UT WOS:000087245200068 ER PT J AU Idemoto, Y Hayakawa, Y Koura, N Richardson, JW Loong, CK AF Idemoto, Y Hayakawa, Y Koura, N Richardson, JW Loong, CK TI Oxygen-content dependence of crystal structure and T-c of (Nd0.675Ce0.325)(2)(Ba0.664Nd0.336)(2)Cu3.00Oy (vol C 329, pg 29, 2000) SO PHYSICA C LA English DT Correction C1 Sci Univ Tokyo, Fac Sci & Technol, Dept Ind Chem, Chiba 2788510, Japan. Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Idemoto, Y (reprint author), Sci Univ Tokyo, Fac Sci & Technol, Dept Ind Chem, 2641 Yamazaki, Chiba 2788510, Japan. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 2000 VL 331 IS 3-4 BP 337 EP 337 DI 10.1016/S0921-4534(00)00017-4 PG 1 WC Physics, Applied SC Physics GA 306JZ UT WOS:000086594700015 ER PT J AU Crabtree, GW Kwok, WK Paulius, LM Petrean, AM Olsson, RJ Karapetrov, G Tobos, V Moulton, WG AF Crabtree, GW Kwok, WK Paulius, LM Petrean, AM Olsson, RJ Karapetrov, G Tobos, V Moulton, WG TI The effect of disorder on the critical points in the vortex phase diagram of YBCO SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT 1st Euroconference on Vortex Matter in Superconductors at Extreme Scales and Conditions CY SEP 18-24, 1999 CL IRAKLION, GREECE SP VORTEX, ESF DE YBCO; Bose glass transition; first order melting; line disorder; vortex phase diagram ID HIGH-TEMPERATURE SUPERCONDUCTORS; UNTWINNED YBA2CU3O7-DELTA; MELTING TRANSITION; SINGLE-CRYSTALS; IRRADIATION; LIQUID; STATE; HEAT; LINE AB The effect of line disorder induced by heavy ion irradiation and of point disorder induced by proton and electron irradiation on the upper and lower critical points in the vortex phase diagram of YBCO is presented. We find that dilute line disorder induces a Bose glass transition at low fields which is replaced at the lower critical point by first order melting at higher fields. Strong pinning point defects raise the lower critical point, while weak pinning point defects have little or no effect on the lower critical point. The upper critical point is lowered by point disorder, bur raised by Line disorder. First order melting is suppressed by point disorder in two ways, by lowering of the upper critical point for weak point pins, or by merging of the upper and lower critical points for strong point pins. The differing responses of the upper and lower critical points to line and point disorder can be understood in a picture of transverse and longitudinal spatial fluctuations. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Michigan State Univ, Dept Phys, E Lansing, MI 48824 USA. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. RP Crabtree, GW (reprint author), Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RI Karapetrov, Goran/C-2840-2008 OI Karapetrov, Goran/0000-0003-1113-0137 NR 28 TC 13 Z9 13 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY PY 2000 VL 332 IS 1-4 BP 71 EP 79 DI 10.1016/S0921-4534(99)00647-4 PG 9 WC Physics, Applied SC Physics GA 317UK UT WOS:000087245200015 ER PT J AU Biemont, E Quinet, P Faenov, AY Skobeleb, I Nilsen, J Romanova, VM Scholz, M Karpinski, L Szydlowski, A AF Biemont, E Quinet, P Faenov, AY Skobeleb, I Nilsen, J Romanova, VM Scholz, M Karpinski, L Szydlowski, A TI Dielectronic structure of 2/-1s transitions of multicharged ions of argon with nuclear charges Z=10-17 SO PHYSICA SCRIPTA LA English DT Article ID NITROGEN ISOELECTRONIC SEQUENCE; SPECTRAL-LINE INTENSITIES; FLUORINE-LIKE IONS; F-LIKE IONS; N = 2-2; OSCILLATOR-STRENGTHS; SATELLITE SPECTRA; ATOMIC DATA; ENERGY-LEVELS; CALCULATED WAVELENGTHS AB A plasma of argon produced with a plasma focus discharge has been observed between 3.8 and 4.2 Angstrom. Spectra registered with a spectral resolution of 0.03 Angstrom/mm show satellite lines of Ar which were measured and compared with two independent theoretical calculations. Seven transitions of Li-like, eleven of Be-like. twelve of B-like, twenty of C-like, nine of N-like, seven of O-like and two of F-like argon have been identified The agreement between the observations and the calculations and also between the two sets of calculations is generally good. C1 Univ Liege, IPNE, B-4000 Liege 1, Belgium. Univ Mons, B-7000 Mons, Belgium. VNIIFIRI, Multicharged Ions Spectra Data Ctr, Mendeleevo 141570, Moscow Region, Russia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. PN Lebedev Phys Inst, Moscow 117924, Russia. IPPLM, Warsaw 49, Poland. Soltan Inst Nucl Studies, Warsaw, Poland. RP Biemont, E (reprint author), Univ Liege, IPNE, Bat B15, B-4000 Liege 1, Belgium. RI Romanova, Vera/M-6922-2015 NR 56 TC 14 Z9 14 U1 0 U2 2 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PD MAY PY 2000 VL 61 IS 5 BP 555 EP 566 DI 10.1238/Physica.Regular.061a00555 PG 12 WC Physics, Multidisciplinary SC Physics GA 311QU UT WOS:000086897000009 ER PT J AU Bowie, JL Garrison, JC Chiao, RY AF Bowie, JL Garrison, JC Chiao, RY TI Stimulated Raman gain in a Lambda-type atomic system with doubly excited transitions SO PHYSICAL REVIEW A LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; QUANTUM INTERFERENCE; LIGHT AMPLIFICATION; LASER; OSCILLATION; RESONANCES; INVERSION; VAPOR AB Measurements of stimulated Raman gain in rubidium vapor are made and compared with a detailed model. Amplification of a weak probe laser is observed in a Lambda-type three-level system that is driven by a strong cw coupling laser. The intensity of the coupling laser is sufficiently strong that it both optically pumps the atomic levels, causing a population inversion in the ground-state hyperfine levels, and drives the stimulated Raman process producing gain. A theory that models all aspects of the gain mechanism is presented. The model includes all interactions between the external fields and the atomic transitions, including those: processes that involve multiple fields interacting with the same transition. Numerical calculations are compared with gain measurements made at several coupling laser intensities and detunings from the D1 line in Rb-85. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Bowie, JL (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94550 USA. NR 29 TC 1 Z9 1 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 MAY PY 2000 VL 61 IS 5 BP art. no. EP 053811 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 312QD UT WOS:000086953200109 ER PT J AU Carney, JPJ Pratt, RH Kissel, L Roy, SC Sen Gupta, SK AF Carney, JPJ Pratt, RH Kissel, L Roy, SC Sen Gupta, SK TI Rayleigh scattering from excited states of atoms and ions SO PHYSICAL REVIEW A LA English DT Article ID INNER-SHELL PHOTOIONIZATION; R-MATRIX CALCULATIONS; X-RAY-SCATTERING; ELASTIC-SCATTERING; LITHIUM; PHOTONS AB Elastic photon scattering from the ground state and various excited states of carbon atoms and ions has been investigated, using the S-matrix formalism, for incident photon energies ranging from 100 eV to 10 keV, contrasting the results obtained for different configurations. The excited states considered include hollow-atom states, where one or more inner shells are completely vacated. Ionic cases are considered as a limit of excitation. Results demonstrate how cross sections for different excited states group together according to shared properties of the configurations, such as the number of K electrons. Cross sections may exhibit deep dips below the K edge, depending on the occupation of the subshells corresponding to the strongest transitions. Scattering from excited states can have significantly larger cross sections than scattering from the ground state, particularly just below the K resonance region, and therefore it needs to be considered in situations where there is a large population of these excited stares. Results are interpreted in terms of form-factor arguments and the qualitative behavior of individual subshell amplitudes. The angular dependence of cross sections can be understood in terms of angle-dependent form factors and anomalous scattering factors, taken to be angle independent. Cases are identified for which excited-state total integrated cross sections are much larger than the corresponding cross sections for scattering from the ground state. Our main results use an averaging over magnetic substates at the level of the amplitude, exact only for fully filled subshells, but generally appropriate for the carbon case considered, which simplifies the discussion and explains most of the general features. We also present results for a hollow lithium atom with and without this approximation to illustrate the differences that can arise in certain circumstances. C1 Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Bose Inst, Dept Phys, Calcutta 700009, W Bengal, India. Univ N Bengal, Univ Sci Instrumentat Ctr, Raja Rammohanpur 734430, W Bengal, India. RP Carney, JPJ (reprint author), Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. NR 42 TC 10 Z9 10 U1 2 U2 8 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 MAY PY 2000 VL 61 IS 5 BP art. no. EP 052714 DI 10.1103/PhysRevA.61.052714 PG 14 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 312QD UT WOS:000086953200068 ER PT J AU Czarnecki, A Melnikov, K Yelkhovsky, A AF Czarnecki, A Melnikov, K Yelkhovsky, A TI Calculation of alpha(2) corrections to parapositronium decay SO PHYSICAL REVIEW A LA English DT Article ID EFFECTIVE-FIELD-THEORY; PRECISION-MEASUREMENT; VACUUM POLARIZATION; POSITRONIUM DECAY; ORTHOPOSITRONIUM; ORDER; MOMENTA; QUARK; WIDTH; STATE AB We present details of our recent calculation of alpha(2) corrections to the parapositronium decay into two photons. These corrections are rather small and our final result for the parapositronium lifetime agrees well with the most recent measurement. Implications for orthopositronium decays are briefly discussed. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Stanford Linear Accelerator Ctr, Theoret Phys Grp, Stanford, CA 94309 USA. Novosibirsk State Univ, Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Novosibirsk State Univ, Dept Phys, Novosibirsk 630090, Russia. RP Czarnecki, A (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 33 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 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2000 VL 61 IS 5 BP art. no. EP 052502 DI 10.1103/PhysRevA.61.052502 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 312QD UT WOS:000086953200043 ER PT J AU Ludziejewski, T Stohlker, T Ionescu, DC Rymuza, P Beyer, H Bosch, F Kozhuharov, C Kramer, A Liesen, D Mokler, PH Stachura, Z Swiat, P Warczak, A Dunford, RW AF Ludziejewski, T Stohlker, T Ionescu, DC Rymuza, P Beyer, H Bosch, F Kozhuharov, C Kramer, A Liesen, D Mokler, PH Stachura, Z Swiat, P Warczak, A Dunford, RW TI Simultaneous excitation and ionization of He-like uranium ions in relativistic collisions with gaseous targets SO PHYSICAL REVIEW A LA English DT Article ID RADIATIVE ELECTRON-CAPTURE; K-SHELL IONIZATION; ATOMIC-COLLISIONS; HEAVY-IONS; 10.8 GEV/NUCLEON; PAIR-PRODUCTION; CROSS-SECTIONS; PROJECTILES; HELIUM; AU79+ AB The process of simultaneous excitation and ionization is investigated for He-like uranium (U90+) ions colliding with Ar, Kr, and Xe targets at an incident energy of 223.2 MeV/u. The two-electron transitions, where one of the ground-state electrons is promoted into the continuum and the other into the L-subshell states of the projectile, are identified by the coincident observation of U Lyman-series radiation and U91+ ions. The experimental cross sections are compared to relativistic calculations based on the independent particle approximation and first-order perturbation theory. It is shown, that simultaneous excitation-ionization occurs preferably at small impact parameters, for which the excitation process is dominated by the monopole part of the interaction potential and the perturbation potential is largest. Good agreement is found between experimental data and calculations for the Ar target. For heavier targets the experimental results are generally smaller than predicted pointing to the invalidity of the first-order perturbation theory in this energy-target atomic number domain. C1 Gesell Schwerionenforsch GmbH, D-64220 Darmstadt, Germany. Soltan Inst Nucl Studies, PL-05400 Swierk, Poland. Univ Frankfurt, Inst Kernphys, D-60486 Frankfurt, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Inst Nucl Phys, PL-31342 Krakow, Poland. Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. Argonne Natl Lab, Argonne, IL 60439 USA. RP Ludziejewski, T (reprint author), Gesell Schwerionenforsch GmbH, D-64220 Darmstadt, Germany. NR 40 TC 17 Z9 17 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 MAY PY 2000 VL 61 IS 5 AR 052706 DI 10.1103/PhysRevA.61.052706 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 312QD UT WOS:000086953200060 ER PT J AU Morin, P Simon, M Miron, C Leclercq, N Kukk, E Bozek, JD Berrah, N AF Morin, P Simon, M Miron, C Leclercq, N Kukk, E Bozek, JD Berrah, N TI Role of bending in the dissociation of selective resonant inner-shell excitation as observed in CO2 SO PHYSICAL REVIEW A LA English DT Article ID RAMAN; STATES; SPECTRA; DECAY; N2O AB Combining high-resolution electron spectroscopy with electron-ion coincidence data, we have been able to show the role of bending excitation in the dissociation of CO2 after C 1s-->Pi(u) resonant excitation. We demonstrate that the predissociation of the dominating A state created through participator decay is not constant along the resonance profile. The interpretation is based on a preferential excitation of high levels of the bending mode at low-photon-energy side of the resonance, which favors the O+ + CO decay channel. C1 Univ Paris 11, LURE, F-91405 Orsay, France. CENS, CEA, DRECAM, SPAM, F-91191 Gif Sur Yvette, France. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Univ Paris 11, LURE, Bat 209D, F-91405 Orsay, France. RI Bozek, John/E-4689-2010; Bozek, John/E-9260-2010; MIRON, Catalin/D-3446-2009 OI Bozek, John/0000-0001-7486-7238; MIRON, Catalin/0000-0002-8302-7158 NR 19 TC 58 Z9 58 U1 0 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2000 VL 61 IS 5 AR 050701 DI 10.1103/PhysRevA.61.050701 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 312QD UT WOS:000086953200004 ER PT J AU Sant'Anna, MM Melo, WS Santos, ACF de Jesus, VLB Shah, MB Sigaud, GM Montenegro, EC Busnengo, HF Corchs, SE Rivarola, RD Gulyas, L AF Sant'Anna, MM Melo, WS Santos, ACF de Jesus, VLB Shah, MB Sigaud, GM Montenegro, EC Busnengo, HF Corchs, SE Rivarola, RD Gulyas, L TI Electronic capture by He2+ from atomic and molecular hydrogen SO PHYSICAL REVIEW A LA English DT Article ID MULTIPLY-CHARGED IONS; CROSS-SECTIONS; HE-2+ IONS; COLLISIONS; IONIZATION; IMPACT; H-2; APPROXIMATION; DEPENDENCE; H+ AB We present absolute measurements of electron-capture cross sections in atomic and molecular hydrogen by alpha particles with energies ranging from 0.5 to 2.75 MeV. The measured single-electron-capture cross sections as well as the ratio sigma(c)(H2)/sigma(c)(H) are compared with several available theories. In particular, a detailed analysis of the role played by two-electron processes in the single-electron capture of H-2 is performed considering a distorted-wave model as a starting point. C1 Queens Univ Belfast, Dept Pure & Appl Phys, Belfast BT7 1NN, Antrim, North Ireland. Univ Nacl Rosario, CONICET, RA-2000 Rosario, Santa Fe, Argentina. RP Sant'Anna, MM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA USA. RI Sigaud, Geraldo/B-6341-2008; santos, antonio/G-2033-2010; Sant'Anna, Marcelo/B-9355-2013 OI santos, antonio/0000-0001-7402-6594; Sant'Anna, Marcelo/0000-0001-5342-5799 NR 43 TC 2 Z9 2 U1 0 U2 2 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 MAY PY 2000 VL 61 IS 5 AR 052717 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 312QD UT WOS:000086953200071 ER PT J AU Zeman, V Armour, EAG Pack, RT AF Zeman, V Armour, EAG Pack, RT TI Treatment of the t mu+D-2 reaction by the methods of quantum reactive scattering SO PHYSICAL REVIEW A LA English DT Article ID QUANTUM REACTIVE SCATTERING; CATALYZED FUSION CYCLE; MOLECULE DT-MU; CROSS-SECTION; RESONANT FORMATION; ENERGY SHIFT; FINITE SIZE; REPRESENTATION; DEEXCITATION; STATES AB We have applied the methods of quantum reactive scattering to the key resonant reaction in the muoncatalyzed fusion (MCF) cycle that leads to the formation of a dt mu muonic molecular ion, in which fusion takes place very rapidly. We have calculated reaction probabilities for the resonances that occur in t mu+D-2 scattering for incident kinetic energies less than 0.6 eV and total angular momentum J(tot)=0. To reduce the six-body problem to a three-body problem, the motions of the electrons were treated in the Born-Oppenheimer (BO) approximation while those of the muon were treated with a sophisticated adiabatic approximation. The resulting three-body potential energy surface (PES) was represented by a pairwise additive approximation. The dt mu part of the PES was scaled to allow it to exhibit the correct binding energy of the crucial (J,v)=(1,1) state. Scattering calculations were carried out using a hyperspherical formulation, and the positions of the resonances were found to occur at energies of a few meV greater than if dt mu is assumed to be a point particle. A comparison of the resonances with the Breit-Wigner formula allowed us to calculate partial widths for back decay, Gamma(e)(Jtot). Once these are known for all significant J(tot), the rate of formation of dt mu can be determined. This rate, next to the sticking fraction, is the most important parameter in determining the rate of the entire MCF cycle. We have also carried out a calculation whereby the muon was treated in a BO formalism and have found significant differences in the final results, demonstrating the importance of treating the muon as accurately as possible. This work represents a successful ab initio calculation of this reaction. C1 Univ Nottingham, Sch Math Sci, Nottingham NG7 2RD, England. Los Alamos Natl Lab, Theoret Div T 12 MS B268, Los Alamos, NM 87545 USA. RP Univ Nottingham, Sch Math Sci, Nottingham NG7 2RD, England. NR 59 TC 6 Z9 6 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 2000 VL 61 IS 5 AR 052713 DI 10.1103/PhysRevA.61.052713 PG 14 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 312QD UT WOS:000086953200067 ER PT J AU Persson, K Ekman, M Ozolins, V AF Persson, K Ekman, M Ozolins, V TI Phonon instabilities in bcc Sc, Ti, La, and Hf SO PHYSICAL REVIEW B LA English DT Article ID GROUP-IV METALS; TRANSITION-METALS; LATTICE-DYNAMICS; DISPERSION; PHASE; PSEUDOPOTENTIALS; TRANSFORMATION; FREQUENCIES; PRESSURE; SYSTEMS AB The lattice dynamics of the elements Sc, Ti, La, and Hf in the bcc structure is studied using the density-functional linear-response theory. The elements exhibit similar phonon instabilities which cover large parts of the Brillouin zone. In particular, the entire T-[1 (1) over bar 1][xi xi 0] branch, where the zone-boundary phonon is responsible for the bcc-->hcp transition, and the L[2/3 2/3 2/3] mode (bcc-->omega) are unstable. However, the T[xi xi xi] branch is unstable for ail elements except Sc, and Ti and Sc exhibit distorted bcc energy minima not seen in the other elements. C1 Royal Inst Technol, SE-10044 Stockholm, Sweden. Sandia Natl Labs, Livermore, CA 94551 USA. RP Persson, K (reprint author), Royal Inst Technol, SE-10044 Stockholm, Sweden. RI Ozolins, Vidvuds/D-4578-2009 NR 41 TC 37 Z9 37 U1 0 U2 13 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 MAY 1 PY 2000 VL 61 IS 17 BP 11221 EP 11224 DI 10.1103/PhysRevB.61.11221 PG 4 WC Physics, Condensed Matter SC Physics GA 312HN UT WOS:000086937700007 ER PT J AU Hettler, MH Hirschfeld, PJ AF Hettler, MH Hirschfeld, PJ TI Order-parameter holes and theory of microwave conductivity in YBa2CU3O7-delta SO PHYSICAL REVIEW B LA English DT Article ID D-WAVE; SURFACE IMPEDANCE; SUPERCONDUCTORS; YBA2CU3O6.95; TEMPERATURE; SUPPRESSION; IMPURITIES AB We propose that the low-temperature discrepancy between simple d-wave models of the microwave conductivity and existing experiments on single crystals of YBa2Cu3O7-delta can be resolved by including the scattering of quasiparticles from "holes'' of the order parameter at impurity sites. Within a framework proposed previously, we find in particular excellent agreement with data of Hosseini et al. on slightly overdoped YBa2Cu3O7-delta samples over the entire temperature range down to about 2-3 K, and for a wide range of frequencies. Remaining discrepancies in the "universal'' regime at very low temperatures are discussed. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. RP Hettler, MH (reprint author), Forschungszentrum Karlsruhe, Postfach 3840, D-76021 Karlsruhe, Germany. RI Hirschfeld, Peter /A-6402-2010 NR 22 TC 18 Z9 19 U1 0 U2 0 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 MAY 1 PY 2000 VL 61 IS 17 BP 11313 EP 11316 DI 10.1103/PhysRevB.61.11313 PG 4 WC Physics, Condensed Matter SC Physics GA 312HN UT WOS:000086937700031 ER PT J AU Cao, D Bridges, F Worledge, DC Booth, CH AF Cao, D Bridges, F Worledge, DC Booth, CH TI Effect of annealing temperature on local distortion of La0.67Ca0.33MnO3 thin films SO PHYSICAL REVIEW B LA English DT Article ID ABSORPTION FINE-STRUCTURE; X-RAY; OXYGEN STOICHIOMETRY; PHASE-DIAGRAM; LA1-XCAXMNO3; SPECTROSCOPY; MAGNETORESISTANCE; LA1-XSRXMNO3; MAGNETISM; TRANSPORT AB Mn K-edge fluorescence data are presented for thin-film samples (3000 Angstrom) of colossal magnetoresistive (CMR) La0.67Ca0.33MnO3: as deposited, and post annealed at 1000 and 1200 K. The local distortion is analyzed in terms of three contributions: static, phonon, and an extra, temperature-dependent, polaron term. The polaron distortion is very small for the as-deposited sample and increases with the annealing temperature. In contrast, the static distortion in the samples decreases with the annealing temperature. Although the local structure of the as-deposited sample shows very little temperature dependence, the change in resistivity with temperature is the largest of these three thin-film samples. The as-deposited sample also has the highest magnetoresistance, which indicates some other mechanism may also contribute to the transport properties of CMR samples. We also discuss the relationship between local distortion and the magnetization of the sample. C1 Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cao, D (reprint author), Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. RI Booth, Corwin/A-7877-2008 NR 22 TC 31 Z9 34 U1 0 U2 3 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 MAY 1 PY 2000 VL 61 IS 17 BP 11373 EP 11378 DI 10.1103/PhysRevB.61.11373 PG 6 WC Physics, Condensed Matter SC Physics GA 312HN UT WOS:000086937700044 ER PT J AU Park, JH Tjeng, LH Tanaka, A Allen, JW Chen, CT Metcalf, P Honig, JM de Groot, FMF Sawatzky, GA AF Park, JH Tjeng, LH Tanaka, A Allen, JW Chen, CT Metcalf, P Honig, JM de Groot, FMF Sawatzky, GA TI Spin and orbital occupation and phase transitions in V2O3 SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-ABSORPTION; METAL-INSULATOR TRANSITIONS; CR-DOPED V2O3; ELECTRONIC-STRUCTURE; PHOTOEMISSION; SPECTROSCOPY; BAND; SPECTRA; SYSTEMS; ENERGY AB Polarization dependent x-ray-absorption measurements were performed on pure and Cr-doped V2O3 single crystals in the antiferromagnetic insulating, paramagnetic insulating, and metallic phases. The orbital occupation of the V 3d(2) ion is found to depend appreciably on the phase, but always with the S= 1 character, requiring an explanation which is beyond the elegant simplicity of the pure one-band Hubbard model or of models in which the a(1g) orbital is projected out by means of a simple dimerization. The results reveal the critical role of the spin and orbital dependence of the on-site 3d-3d Coulomb energy, and a mechanism is proposed to explain the closing or opening of the band gaps which are of much higher energy scale than the transition temperatures. C1 Univ Michigan, Randall Lab, Ann Arbor, MI 48109 USA. AT&T Bell Labs, Murray Hill, NJ 07974 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Michigan, Randall Lab, Ann Arbor, MI 48109 USA. Univ Groningen, Ctr Mat Sci, Solid State Phys Lab, NL-9747 AG Groningen, Netherlands. Hiroshima Univ, Fac Sci, Dept Mat Sci, Higashihiroshima 724, Japan. Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. RP Park, JH (reprint author), POSTECH, Dept Phys, Pohang 790784, South Korea. RI Sawatzky, George/D-2997-2012; de Groot, Frank/A-1918-2009 NR 48 TC 141 Z9 141 U1 2 U2 28 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 MAY 1 PY 2000 VL 61 IS 17 BP 11506 EP 11509 DI 10.1103/PhysRevB.61.11506 PG 4 WC Physics, Condensed Matter SC Physics GA 312HN UT WOS:000086937700060 ER PT J AU Zheludev, A Maslov, S Yokoo, T Akimitsu, J Raymond, S Nagler, SE Hirota, K AF Zheludev, A Maslov, S Yokoo, T Akimitsu, J Raymond, S Nagler, SE Hirota, K TI Role of single-ion excitations in the mixed-spin quasi-one-dimensional quantum antiferromagnet Nd2BaNiO5 SO PHYSICAL REVIEW B LA English DT Article ID HALDANE-GAP EXCITATIONS; STAGGERED MAGNETIC-FIELD; SOFT-MODE TRANSITION; CHAIN; Y2BANIO5; (NDXY1-X)(2)BANIO5; SCATTERING; PR2BANIO5; R2BANIO5; ORDER AB Inelastic neutron scattering experiments on Nd2BaNiO5 single crystals and powder samples are used to study the dynamic coupling of one-dimensional Haldane-gap excitations in the S=1 Ni2+-chains to local crystal-field transitions, associated with the rare earth ions. Substantial interference between the two types of excitations is observed even in the one-dimensional paramagnetic phase. Despite that, the results provide solid justification for the previously proposed "static staggered field" model for R2BaNiO5 nickelates. The observed behavior is qualitatively explained by a simple chain-random-phase-approximation model. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Aoyama Gakuin Univ, Dept Phys, Setagaya Ku, Tokyo 157, Japan. Univ Geneva, CH-1211 Geneva 4, Switzerland. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Tohoku Univ, Dept Phys, Aoba Ku, Sendai, Miyagi 9808578, Japan. RP Zheludev, A (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Hirota, Kazuma/C-6797-2008; Nagler, Stephen/B-9403-2010; Nagler, Stephen/E-4908-2010; Maslov, Sergei/C-2397-2009 OI Nagler, Stephen/0000-0002-7234-2339; Maslov, Sergei/0000-0002-3701-492X NR 22 TC 14 Z9 14 U1 0 U2 1 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 MAY 1 PY 2000 VL 61 IS 17 BP 11601 EP 11612 DI 10.1103/PhysRevB.61.11601 PG 12 WC Physics, Condensed Matter SC Physics GA 312HN UT WOS:000086937700071 ER PT J AU Yan, H Jung, J Darhmaoui, H Ren, ZF Wang, JH Kwok, WK AF Yan, H Jung, J Darhmaoui, H Ren, ZF Wang, JH Kwok, WK TI Fast vortex motion and filamentary phase separation in high-T-c thin films SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; CRITICAL-CURRENT-DENSITY; MAGNETIC-RELAXATION; COLUMNAR DEFECTS; FLUX-CREEP; YBA2CU3O7-DELTA CRYSTALS; TRANSPORT-PROPERTIES; O CRYSTALS; BEHAVIOR; INHOMOGENEITIES AB We investigated the temperature dependence of the normalized logarithmic relaxation rate S(T) and the corresponding temperature dependence of the critical current I-c(T) in high-T-c thin films (YBCO-123, TlBCCO-2212, -2223, and -2201, and Bi-2212). Experiments have been performed using persistent critical currents flowing in the a-b planes of ring-shaped samples. The magnitude of I, and the relaxation rate have been extracted from the measurement of the self-field of the current. The results revealed a relationship between I-c(T) and S(T). I-c(T) in YBCO is a superposition of two universal components: an underdoped Ginzburg-Landau- (GL) like one with I-c(T)proportional to(T-c- T)(3/2) and T-c between 40 and 60 K, and an Ambegaokar-Baratoff-like one close to an optimum doping. The results revealed that when the amount of the GL-like phase increases above a certain threshold value, a peak appears in S(T) at temperatures of 20-30 K, and its height gradually increases with the magnitude of I-c at 10 K for this phase. We discuss similarities between these results and those reported for YBCO crystals with columnar defects. The presence of two maxima in S(T) have been observed for TlBCCO films that are composed of three different phases, at temperatures close to T, of two underdoped components. The studies imply that the filamentary phase separation on a nanometer scale level in the a-b planes is responsible for the changes in vortex dynamics. C1 Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. SUNY Buffalo, Dept Chem, Buffalo, NY 14260 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Alakhawayn Univ, Sch Sci & Engn, Ifrane 5300, Morocco. Boston Coll, Dept Phys, Chestnut Hill, MA 02467 USA. RP Jung, J (reprint author), Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. EM jung@phys.ualberta.ca RI Ren, Zhifeng/B-4275-2014 NR 35 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 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2000 VL 61 IS 17 BP 11711 EP 11721 DI 10.1103/PhysRevB.61.11711 PG 11 WC Physics, Condensed Matter SC Physics GA 312HN UT WOS:000086937700086 ER PT J AU Muller, J Lang, M Steglich, F Schlueter, JA Kini, AM Geiser, U Mohtasham, J Winter, RW Gard, GL Sasaki, T Toyota, N AF Muller, J Lang, M Steglich, F Schlueter, JA Kini, AM Geiser, U Mohtasham, J Winter, RW Gard, GL Sasaki, T Toyota, N TI Comparative thermal-expansion study of beta ''-(ET)(2)SF5CH2CF2SO3 and kappa-(ET)(2)Cu(NCS)(2): Uniaxial pressure coefficients of T-c and upper critical fields SO PHYSICAL REVIEW B LA English DT Article ID ORGANIC SUPERCONDUCTOR KAPPA-(BEDT-TTF)2CU(NCS)2; MAGNETIC-FIELD; TRANSPORT-PROPERTIES; SINGLE-CRYSTALS; BEDT-TTF; HEAT; BIS(ETHYLENEDITHIO)TETRATHIAFULVALENE; YBA2CU3O7-DELTA; FLUCTUATIONS; TEMPERATURE AB We report high-resolution measurements of the coefficient of thermal expansion, alpha = l(-1) x (partial derivative l/partial derivative T), on single crystals of the organic superconductors beta "- (ET)(2)SF5CH2CF2SO3 and kappa-(ET)(2)Cu(NCS)(2). For both salts we find large and highly anisotropic phase-transition anomalies at T-c. Combining these data with literature results on the specific heat via the Ehrenfest relation, the uniaxial pressure coefficients of T-c can be determined. Most remarkably, a strikingly similar in-plane vs out-of-plane anisotropy is found for both compounds: the strong suppression of T-c observed in hydrostatic-pressure experiments is dominated by a huge negative uniaxial stress effect perpendicular to the conducting planes. Therefore we expect that an increase of T-c in this class of superconductors can be obtained by enlarging the distance between the conducting layers. Application of magnetic fields perpendicular to the planes for the beta"-(ET)(2)SF5CH2CF2SO3 salt were found to result in pronounced superconducting fluctuation effects and scaling behavior in alpha(T,B). Owing to the pronounced phase-transition anomalies in alpha(T,B) at T-c, our measurements allow for an accurate determination of the upper critical fields. We find B-c2(perpendicular to)(0) = (1.4+/-0.2) T and B-c2(parallel to) (0) = (10.4+/-0.5) T for fields perpendicular and parallel to the conducting planes, respectively. C1 Max Planck Inst Chem Phys Solids, D-01187 Dresden, Germany. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Portland State Univ, Dept Chem, Portland, OR 97207 USA. Tohoku Univ, Inst Mat Res, Sendai, Miyagi 980, Japan. Tohoku Univ, Fac Sci, Dept Phys, Sendai, Miyagi 980, Japan. RP Muller, J (reprint author), Max Planck Inst Chem Phys Solids, D-01187 Dresden, Germany. RI Sasaki, Takahiko/F-1231-2010; Kini, Aravinda/F-4467-2012 OI Sasaki, Takahiko/0000-0002-0767-5428; NR 31 TC 37 Z9 37 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 MAY 1 PY 2000 VL 61 IS 17 BP 11739 EP 11744 DI 10.1103/PhysRevB.61.11739 PG 6 WC Physics, Condensed Matter SC Physics GA 312HN UT WOS:000086937700089 ER PT J AU Gutmann, M Billinge, SJL Brosha, EL Kwei, GH AF Gutmann, M Billinge, SJL Brosha, EL Kwei, GH TI Possible charge inhomogeneities in the CuO2 planes of YBa2Cu3O6+x (x=0.25,0.45,0.65,0.94) from pulsed neutron diffraction SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-ABSORPTION; POWDER-DIFFRACTION; LOCAL-STRUCTURE; YBA2CU3O7-DELTA; SUPERCONDUCTORS; DISTORTIONS; REFINEMENT; CRYSTALS; RANGE AB The atomic pair distribution functions (PDFs) of four powder samples of YBa2Cu3O6+x (x = 0.25, 0.45, 0.65, 0.94) at 15 K have been measured by means of pulsed neutron diffraction. The PDF is modeled using a full-profile fitting approach to yield structural parameters. In contrast to earlier x-ray absorption fine structure work we find no evidence of a split apical oxygen site. However, a slightly improved fit over the average crystallographic model results when the planar Cu(2) site is split along the c direction. This is interpreted in terms of charge inhomogeneities in the CuO2 planes. C1 Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Michigan State Univ, Ctr Fundamental Mat Res, E Lansing, MI 48824 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. NR 40 TC 16 Z9 16 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 2000 VL 61 IS 17 BP 11762 EP 11768 DI 10.1103/PhysRevB.61.11762 PG 7 WC Physics, Condensed Matter SC Physics GA 312HN UT WOS:000086937700092 ER PT J AU Paulius, LM Kwok, WK Olsson, RJ Petrean, AM Tobos, V Fendrich, JA Crabtree, GW Burns, CA Ferguson, S AF Paulius, LM Kwok, WK Olsson, RJ Petrean, AM Tobos, V Fendrich, JA Crabtree, GW Burns, CA Ferguson, S TI Evolution of the vortex phase diagram in YBa2Cu3O7-delta with random point disorder SO PHYSICAL REVIEW B LA English DT Article ID UNTWINNED YBA2CU3O7-DELTA; SINGLE-CRYSTALS; ELECTRON-IRRADIATION; MELTING TRANSITION; ORDER; IRREVERSIBILITY; IMPURITIES; TRANSPORT; DEFECTS; LIQUID AB We demonstrate the gradual evolution of the first-order vortex melting transition into a continuous transition with the systematic addition of point disorder induced by proton irradiation. The evolution occurs via the decrease of the upper critical point and the increase of the lower critical point. The collapse of the first-order melting transition occurs when the two critical points merge. We compare these results with the effects of electron irradiation on the first-order transition. C1 Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Argonne Natl Lab, Sci & Technol Ctr Superconduct, Argonne, IL 60439 USA. RP Paulius, LM (reprint author), Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. NR 26 TC 25 Z9 25 U1 0 U2 1 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 MAY 1 PY 2000 VL 61 IS 18 BP 11910 EP 11913 PG 4 WC Physics, Condensed Matter SC Physics GA 312QA UT WOS:000086952900015 ER PT J AU Reichhardt, C Scalettar, RT Zimanyi, GT Gronbech-Jensen, N AF Reichhardt, C Scalettar, RT Zimanyi, GT Gronbech-Jensen, N TI Phase-locking of vortex lattices interacting with periodic pinning SO PHYSICAL REVIEW B LA English DT Article ID ANTIDOT LATTICE; THIN-FILMS; LOGARITHMIC INTERACTIONS; SUPERCONDUCTING FILM; REGULAR ARRAY; MAGNETIC DOTS; VORTICES; SUMMATION; DEFECTS; MEDIA AB We examine Shapiro steps for vortex lattices interacting with periodic pinning arrays driven by ac and de currents. The vortex flow occurs by the motion of the interstitial vortices through the periodic potential generated by the vortices that remain pinned at the pinning sites. Shapiro steps are observed for fields B-phi5 indicating strong coupling between the Ce3+ ion and lattice. Temperature dependence of the band centroids exhibits contrasting behavior that is dominated by higher-order coupling terms in the linear harmonic oscillator model or by crystal-field effects. Oscillator strengths of the 4f-->5d transitions are calculated from Smakula's formula and knowledge of the Ce3+ distribution between the two crystallographically inequivalent sites. Values for peaks b, c, and d range from approximately 0.003 to 0.004, and peak a spans magnitude approximately 0.012 to 0.018. From the known correlation between average Ce3+-ion-ligand distance and oscillator strength, we tentatively conclude that peak a is correlated with the seven-oxygen-coordinated site, and peaks b, c, and d are associated with the six-oxygen-coordinated site. These results support the previously proposed two-activation-center model and identify the centers as the two crystallographically inequivalent substitutional sites. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Cooke, DW (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 24 TC 37 Z9 39 U1 1 U2 7 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 MAY 1 PY 2000 VL 61 IS 18 BP 11973 EP 11978 DI 10.1103/PhysRevB.61.11973 PG 6 WC Physics, Condensed Matter SC Physics GA 312QA UT WOS:000086952900024 ER PT J AU Ujfalussy, B Faulkner, JS Moghadam, NY Stocks, GM Wang, Y AF Ujfalussy, B Faulkner, JS Moghadam, NY Stocks, GM Wang, Y TI Calculating properties with the polymorphous coherent-potential approximation SO PHYSICAL REVIEW B LA English DT Article ID RANDOM SUBSTITUTIONAL ALLOYS; ELECTRONIC-STRUCTURE CALCULATIONS; INDIVIDUAL PAIR DISPLACEMENTS; DENSITY-FUNCTIONAL THEORY; TOTAL-ENERGY CALCULATIONS; RANDOM METALLIC ALLOYS; MOLECULAR-DYNAMICS; FIRST-PRINCIPLES; QUANTUM FORCES; BAND-STRUCTURE AB The formulas for calculating properties of an alloy such as the density of states, the charge density, and the Bloch spectral density function are derived from multiple-scattering theory for the polymorphous coherent-potential approximation (PCPA). The chemical shifts obtained for three alloy systems using the PCPA, the Korringa-Kohn-Rostoker CPA, and the locally self-consistent multiple-scattering method are compared with experiment A significant improvement in the treatment of Coulomb effects is achieved using the PCPA with only a little more computational effort than for the older isomorphous CPA's. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37830 USA. Florida Atlantic Univ, Dept Phys, Boca Raton, FL 33431 USA. Florida Atlantic Univ, Alloy Res Ctr, Boca Raton, FL 33431 USA. RP Ujfalussy, B (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37830 USA. RI Ujfalussy, Balazs/A-8155-2013; Stocks, George Malcollm/Q-1251-2016 OI Ujfalussy, Balazs/0000-0003-3338-4699; Stocks, George Malcollm/0000-0002-9013-260X NR 71 TC 25 Z9 25 U1 0 U2 3 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 MAY 1 PY 2000 VL 61 IS 18 BP 12005 EP 12016 DI 10.1103/PhysRevB.61.12005 PG 12 WC Physics, Condensed Matter SC Physics GA 312QA UT WOS:000086952900028 ER PT J AU Criado, A Jimenez-Ruiz, M Cabrillo, C Bermejo, FJ Fernandez-Perea, R Fischer, HE Trouw, FR AF Criado, A Jimenez-Ruiz, M Cabrillo, C Bermejo, FJ Fernandez-Perea, R Fischer, HE Trouw, FR TI Rotational dynamics in the plastic-crystal phase of ethanol: Relevance for understanding the dynamics during the structural glass transition SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-DYNAMICS; NEUTRON-SCATTERING; DISORDERED MATTER; LIQUID; HEXACHLOROETHANE; SIMULATION AB The reorientational dynamics within the rotationally disordered cubic plastic phase of solid ethanol is investigated by means of the concurrent use of computer molecular dynamics and quasielastic neutron scattering. Motions involving widely different time scales are shown to take place above the calorimetric "glass transition" which is centered at T(g)approximate to 97 K. These correspond to well-defined reorientations belonging to the cubic point group. The dynamics of this solid exhibits features remarkably close to those of the supercooled liquid that can exist at the same temperature. Such similitude of dynamic behavior serves to provide some clues for the understanding of the nature of molecular motions at temperatures close to the canonical liquid-->glass transition. C1 Univ Seville, CSIC, Inst Ciencia Mat Sevilla, E-41080 Seville, Spain. Univ Seville, CSIC, Dept Fis Mat Condensada, E-41080 Seville, Spain. Consejo Super Invest Cient, Madrid 28006, Spain. Argonne Natl Lab, Argonne, IL 60439 USA. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. RP Criado, A (reprint author), Univ Seville, CSIC, Inst Ciencia Mat Sevilla, POB 1065, E-41080 Seville, Spain. RI Fernandez-Perea, Ricardo/E-9118-2016; Fischer, Henry/D-5299-2012 OI Fernandez-Perea, Ricardo/0000-0002-4011-2344; Fischer, Henry/0000-0002-1204-0750 NR 28 TC 43 Z9 45 U1 0 U2 14 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 MAY 1 PY 2000 VL 61 IS 18 BP 12082 EP 12093 DI 10.1103/PhysRevB.61.12082 PG 12 WC Physics, Condensed Matter SC Physics GA 312QA UT WOS:000086952900037 ER PT J AU Fishman, RS Lee, WT Liu, SH Mandrus, D Robertson, JL Song, KJ Thompson, JR AF Fishman, RS Lee, WT Liu, SH Mandrus, D Robertson, JL Song, KJ Thompson, JR TI Structural and magnetic phase transitions in Mn-Ni alloys SO PHYSICAL REVIEW B LA English DT Article ID SPIN-DENSITY WAVE; FE/CR(001) SUPERLATTICES; LATTICE DISTORTION; GAMMA; MANGANESE AB When the Ni concentration exceeds about 18%, Mn-Ni alloys were expected to support two different noncollinear spin-density wave (SDW) phases. A triple-e SDW with moments along the crystal diagonals was believed to appear in the fee phase between T-N and T-t. Below T-t, the fct phase with c>a was believed to contain a double-e SDW with moments in the ab plane and at 45 degrees angles from the crystal axes. Based on resistivity, neutron-scattering, and susceptibility measurements, we show that the structural and magnetic phase transitions in a Mn1-xNix alloy with x approximate to 0.20 are actually distinct, with the structural phase transition at T-t approximate to 250 K lying far above the magnetic transition at T(m)approximate to 125 K. A Hamiltonian which includes elastic, mag netoelastic, and noncollinearity energies is used to describe these two transitions. In the tetragonal phase between T-t and T-m, our model predicts a new SDW phase with moments tilted away from the crystal diagonals toward the ab plane. The energy gap in the spin-wave spectrum is predicted to change discontinuously at T-m. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Tennessee, Knoxville, TN 37996 USA. RP Fishman, RS (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Fishman, Randy/C-8639-2013; Mandrus, David/H-3090-2014 NR 31 TC 10 Z9 10 U1 1 U2 2 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 MAY 1 PY 2000 VL 61 IS 18 BP 12159 EP 12168 DI 10.1103/PhysRevB.61.12159 PG 10 WC Physics, Condensed Matter SC Physics GA 312QA UT WOS:000086952900045 ER PT J AU Ahmad, I Dunford, RW Esbensen, H Gemmell, DS Kanter, EP Rutt, U Southworth, SH AF Ahmad, I Dunford, RW Esbensen, H Gemmell, DS Kanter, EP Rutt, U Southworth, SH TI Nuclear excitation by electronic transition in Os-189 SO PHYSICAL REVIEW C LA English DT Article ID ELLIPTIC MULTIPOLE WIGGLER; X-RAY; AUGER AB Monochromatic x rays have been used to explore the phenomenon of nuclear excitation by electronic transition (NEET) in the Os-189 atomic/nuclear system. A new theoretical approach to calculating this process has also been developed and predicts a value for the "NEET probability," P-NEET, of 1 3x10(-10). P-NEET is the probability that a given atomic excitation (in this case a K vacancy), will result in the excitation of a specific nuclear state (in this case the 69.5-keV level in Os-189). This value is much lower than most of the calculated values given in the literature for this system. Our measurement gives the result P-NEET <9x10(-10), an upper limit which is several orders of magnitude lower than the values found in previous measurements, but which is consistent with the new calculation. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Ahmad, I (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 22 TC 35 Z9 36 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 MAY PY 2000 VL 61 IS 5 AR 051304 DI 10.1103/PhysRevC.61.051304 PG 5 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000004 ER PT J AU Brown, CM Milosevich, Z Kaplan, M Vardaci, E DeYoung, PA Whitfield, JP Peterson, D Dykstra, C Karol, PJ McMahan, MA AF Brown, CM Milosevich, Z Kaplan, M Vardaci, E DeYoung, PA Whitfield, JP Peterson, D Dykstra, C Karol, PJ McMahan, MA TI Light-charged-particle emission in the matched reactions 280 MeV Ar-40+Al-27 and 670 MeV Mn-55+C-12: Coincidence results SO PHYSICAL REVIEW C LA English DT Article ID COMPOSITE NUCLEI; HE-4; H-1; KR-86+CU-63; EVAPORATION; FUSION AB Exclusive measurements of light-charged-particle (H-1, H-2, and He-4) energy spectra, angular distributions, and emission multiplicities are reported for the two reactions Ar-40+ Al-27 and Mn-55+ C-12 at a matched excitation energy of 127 MeV. Comparisons are made with statistical model predictions for the evaporative processes in these reactions, which can be characterized as emissions from rotational-energy-dominated systems. The model simulations do well in reproducing a broad range of angular distribution data and the He-4/H-1 cross-section ratio, using spin distributions derived from fusion cross-section systematics. The same model parameters, however, predict particle energy spectra and coincidence cross sections which are inconsistent with the measurements for both reactions. These results support previous conclusions from model comparisons with inclusive data, and suggest fundamental flaws in the statistical model as applied to light-mass, high-spin, nuclear systems. C1 Carnegie Mellon Univ, Dept Chem, Pittsburgh, PA 15213 USA. Hope Coll, Dept Phys, Holland, MI 49423 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Brown, CM (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-414, Livermore, CA 94551 USA. NR 22 TC 3 Z9 3 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 MAY PY 2000 VL 61 IS 5 AR 054611 DI 10.1103/PhysRevC.61.054611 PG 11 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000032 ER PT J AU Collins, CB Davanloo, F Rusu, AC Iosif, MC Zoita, NC Camase, DT Hicks, JM Karamian, SA Ur, CA Popescu, II Dussart, R Pouvesle, JM Kirischuk, VI Strilchuk, NV McDaniel, P Crist, CE AF Collins, CB Davanloo, F Rusu, AC Iosif, MC Zoita, NC Camase, DT Hicks, JM Karamian, SA Ur, CA Popescu, II Dussart, R Pouvesle, JM Kirischuk, VI Strilchuk, NV McDaniel, P Crist, CE TI gamma emission from the 31-yr isomer of Hf-178 induced by x-ray irradiation SO PHYSICAL REVIEW C LA English DT Article ID DEPOPULATION AB A sample containing 6.3x10(14) nuclei of the 16(+) isomer of Hf-178 having a half life of 31 years and excitation energy of 2.446 MeV was irradiated with x-ray pulses derived from a device operated at 15 mA to produce bremsstrahlung radiation with an end point energy set to be 63 keV. Gamma spectra of the isomeric target were taken with two independent Ge detectors. Intensities of the 213.4 keV (4(+)-->2(+)) and 325.5 keV (6(+)-->4(+)) transitions in the ground state band of Hf-178 were found to increase when irradiated. The largest enhancement was 1.6+/-0.3% measured in the 213.4 keV transition. Such an accelerated decay of the Hf-178 isomer is consistent with an integrated cross section exceeding 2.2x10(-22) cm(2) keV if the resonant absorption takes place below 20 keV as indicated by the use of selective absorption filters in the irradiating beam. C1 Univ Texas, Ctr Quantum Elect, Richardson, TX 75083 USA. Joint Inst Nucl Res, Dubna 141980, Russia. H Hulubei Natl Inst Phys & Nucl Engn, Bucharest, Romania. IGE Fdn, Bucharest, Romania. Univ Orleans, CNRS, GREMI, Orleans, France. Ctr Sci, Inst Nucl Res, Kiev, Ukraine. USAF, Res Lab, DEPA, Kirtland AFB, Albuquerque, NM 87123 USA. Sandia Natl Labs, Albuquerque, NM 87123 USA. RP Collins, CB (reprint author), Univ Texas, Ctr Quantum Elect, Richardson, TX 75083 USA. RI Zoita, Nicolae Catalin/F-9868-2013 OI Zoita, Nicolae Catalin/0000-0002-8337-9559 NR 11 TC 41 Z9 45 U1 0 U2 10 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 MAY PY 2000 VL 61 IS 5 AR 054305 DI 10.1103/PhysRevC.61.054305 PG 7 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000017 ER PT J AU Csernai, LP Ellis, PJ Jeon, S Kapusta, JI AF Csernai, LP Ellis, PJ Jeon, S Kapusta, JI TI Dynamical evolution of the scalar condensate in heavy ion collisions SO PHYSICAL REVIEW C LA English DT Article ID DISORIENTED CHIRAL CONDENSATE; FINITE-TEMPERATURE; PHASE-TRANSITION; FIELD-THEORY; DISSIPATION; FLUCTUATIONS AB We derive the effective coarse-grained field equation for the scalar condensate of the linens sigma model in a simple and straightforward manner using linear response theory. The dissipative coefficient is calculated consistently at tree level on the basis of the physical processes of sigma-meson decay and of thermal sigma mesons and pions knocking sigma mesons out of the condensate. The field equation is solved for hot matter undergoing either one- or three-dimensional expansion and cooling in the aftermath of a high energy nuclear collision. The results show that the time constant far returning the scaler condensate to thermal equilibrium is of order 2 fm/c. C1 Univ Bergen, Dept Phys, N-5007 Bergen, Norway. KFKI, Res Inst Particle & Nucl Phys, H-1525 Budapest, Hungary. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. CERN, Div TH, CH-1211 Geneva 23, Switzerland. RP Univ Bergen, Dept Phys, N-5007 Bergen, Norway. EM csernai@sentef2.fi.uib.no; ellis@physics.spa.umn.edu; jeon@nta2.lbl.gov; kapusta@physics.spa.umn.edu NR 31 TC 4 Z9 4 U1 1 U2 1 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 MAY PY 2000 VL 61 IS 5 AR 054901 DI 10.1103/PhysRevC.61.054901 PG 9 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000039 ER PT J AU Davids, CN Esbensen, H AF Davids, CN Esbensen, H TI Decay rates of spherical and deformed proton emitters SO PHYSICAL REVIEW C LA English DT Article ID NUCLEI AB Using Green's function techniques, we derive expressions for the width of a proton decaying state in spherical and deformed nuclei. We show that the proton decay widths calculated by the "exact" expressions of Maglione et al. are equivalent to the distorted wave expressions of Bugrov et al., and that of Aberg et al. in the spherical case. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Davids, CN (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 14 TC 47 Z9 49 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 MAY PY 2000 VL 61 IS 5 AR 054302 DI 10.1103/PhysRevC.61.054302 PG 5 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000014 ER PT J AU Elliott, JB Hirsch, AS AF Elliott, JB Hirsch, AS TI Standard thermodynamic quantities as determined via models of nuclear multifragmentation SO PHYSICAL REVIEW C LA English DT Article ID GAS PHASE-TRANSITION; 1A GEV GOLD; STATISTICAL MULTIFRAGMENTATION; FINITE NUCLEI; LIQUID; COLLISIONS; YIELDS; MATTER; FRAGMENTATION; COEXISTENCE AB Both simple and sophisticated models are frequently used in an attempt to understand how real nuclei breakup when subjected to large excitation energies, a process known as nuclear multifragmentation. Many of these models assume equilibrium thermodynamics and produce results often interpreted as evidence of a phase transition. This work examines one class of models and employs standard thermodynamical procedures to explore the possible existence and nature of a phase transition. The role of various terms, e.g., Coulomb and surface energy, is discussed. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Purdue Univ, W Lafayette, IN 47907 USA. RP Elliott, JB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 35 TC 22 Z9 22 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 MAY PY 2000 VL 61 IS 5 AR 054605 DI 10.1103/PhysRevC.61.054605 PG 17 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000026 ER PT J AU Esbensen, H Hencken, K AF Esbensen, H Hencken, K TI Systematic study of B-8 breakup cross sections SO PHYSICAL REVIEW C LA English DT Article ID COULOMB DISSOCIATION; HALO NUCLEI; E2 TRANSITIONS; PROTON HALO; RADII; MEV/NUCLEON; SCATTERING; BE-7 AB Breakup cross sections of B-8 are analyzed in a two-body structure model, with an inert Be-7 core and a loosely bound valence proton. The nuclear induced breakup is calculated in an eikonal approximation, and Coulomb dissociation is calculated to first order. There is a strong correlation within this model between the total E1 strength and the one-proton removal cross section sigma(1p). Thus we find that the measured values of sigma(1p) For a carbon target are consistent with the E1 strength extracted in recent Coulomb dissociation experiments. The predicted sigma(1p) values on high-Z targets are significantly larger than measured. We discuss how this discrepancy can be reduced by improving the description of Coulomb dissociation. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. RP Esbensen, H (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 27 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 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 2000 VL 61 IS 5 AR 054606 DI 10.1103/PhysRevC.61.054606 PG 8 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000027 ER PT J AU Giannelli, RA Ritchie, BG Applegate, JM Beck, E Beck, J Vanderpool, AO Morris, CL Rahwool-Sullivan, M Jones, MK Ransome, RD Yadav, M Watson, DL Oganesjan, KO Pasyuk, EA Guber, FF Reshetin, AI AF Giannelli, RA Ritchie, BG Applegate, JM Beck, E Beck, J Vanderpool, AO Morris, CL Rahwool-Sullivan, M Jones, MK Ransome, RD Yadav, M Watson, DL Oganesjan, KO Pasyuk, EA Guber, FF Reshetin, AI TI Multiproton final states in positive pion absorption below the Delta(1232) resonance SO PHYSICAL REVIEW C LA English DT Article ID CROSS-SECTIONS; LIGHT-NUCLEI; ENERGY-DEPENDENCE; DELTA-RESONANCE; HEAVY-NUCLEI; HE-3; EMISSION; REGION; O-16; C-12 AB Inclusive cross sections for positive pion absorption leading to final states including two or more protons have been measured with a large solid angle detector for incident pion energies from 30 to 135 MeV for targets with A=2-208. The mass dependences for the inclusive ( pi(+),2p), ( pi(+),3p), and total absorption cross sections for multiproton final states were found to be proportional to A(n) with n approximate to 0.5. These cross sections also were observed to have an energy dependence at energies below 150 MeV reflective of the importance of the Delta(1232) resonance, similar to that observed for pi d-->pp. The inclusive cross sections for ( pi(+),4p) were found to be less than 10 mb for all targets at all energies. Estimates were also obtained for cross sections for pion absorption leading to 2p 1n and 3p 1n final states. Quasideuteron absorption contributions increase slowly with A, and the energy dependence of those contributions mirrors that for pi d-->pp. The data obtained here for multiproton final states indicate that a significant fraction of absorption events, increasing with A, most likely arises from final states containing fewer than two protons. C1 Arizona State Univ, Tempe, AZ 85287 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Univ York, York YO10 5DAD, N Yorkshire, England. Joint Inst Nucl Res, Dubna 141980, Moscow Region, Russia. Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. RP Giannelli, RA (reprint author), USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. RI Guber, Fedor/I-4271-2013 OI Guber, Fedor/0000-0001-8790-3218 NR 46 TC 11 Z9 11 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 MAY PY 2000 VL 61 IS 5 AR 054615 DI 10.1103/PhysRevC.61.054615 PG 18 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000036 ER PT J AU Hicks, K Gladyshev, V Baghaei, H Caracappa, A Cichocki, A Deininger, R Finlay, R Gresko, T Hoblit, S Khandaker, M Kistner, O Li, FX Lindgren, R Lucas, M Miceli, L Norum, B Rapaport, J Sandorfi, A Sealock, R Smith, LC Thorn, C Thornton, S Whisnant, CS Willits, D Wright, LE AF Hicks, K Gladyshev, V Baghaei, H Caracappa, A Cichocki, A Deininger, R Finlay, R Gresko, T Hoblit, S Khandaker, M Kistner, O Li, FX Lindgren, R Lucas, M Miceli, L Norum, B Rapaport, J Sandorfi, A Sealock, R Smith, LC Thorn, C Thornton, S Whisnant, CS Willits, D Wright, LE TI The O-16(->/gamma,pi(-)p)reaction at E-gamma similar or equal to-300 MeV SO PHYSICAL REVIEW C LA English DT Article ID NUCLEUS ELASTIC-SCATTERING; DELTA-RESONANCE REGION; PION-PHOTOPRODUCTION; PROTON-KNOCKOUT; DELTA(1232); PHOTONS; ENERGY AB Cross sections are presented for the O-16(<(gamma)over right arrow>, pi(-) p) reaction at incident photon energies between 290 and 325 MeV. The data are presented for specific proton and pion angles as a function of proton energy, which are compared with calculations in a local distorted wave impulse approximation model. The results are in agree ment at most kinematics, although at some kinematics the data and calculations disagree by a factor of 2 or more. These data do not support the conclusion of a large modification to the mass of the Delta resonance in the nucleus. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Ohio Univ, Dept Phys & Astron, Athens, OH 45701 USA. Univ S Carolina, Dept Phys, Columbia, SC 29208 USA. George Washington Univ, Dept Phys, Washington, DC 20052 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22903 USA. Virginia Polytech Inst & State Univ, Dept Phys, Blacksburg, VA 24061 USA. RP Hicks, K (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 25 TC 4 Z9 4 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 MAY PY 2000 VL 61 IS 5 AR 054609 DI 10.1103/PhysRevC.61.054609 PG 9 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000030 ER PT J AU Hindi, MM Larimer, RM Norman, EB Rech, GA AF Hindi, MM Larimer, RM Norman, EB Rech, GA TI Internal bremsstrahlung endpoint energy of Mn-54 SO PHYSICAL REVIEW C LA English DT Article ID COSMIC-RAYS AB For Mn-54 there is a discrepancy between the Q(EC) obtained from the endpoint energy of the internal bremsstrahlung (IB) spectrum which accompanies the electron capture decay (Q(EC)= 1353+/-8 keV) and that obtained from the accepted mass differences (Q(EC)= 1377+/-1 keV). This Q value is needed to deduce the partial-half life of the astrophysically interesting beta(-) decay of Mn-54 from the recently measured beta(+) partial half-life. To resolve this discrepancy, we have remeasured the endpoint energy of the IB spectrum, by recording coincidences between the IB and the 835-keV gamma ray, both detected in Compton-suppressed Ge detectors. The Q(EC) We deduce is 1379+/-8 keV, in agreement with the accepted mass differences. C1 Tennessee Technol Univ, Dept Phys, Cookeville, TN 38505 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Hindi, MM (reprint author), Tennessee Technol Univ, Dept Phys, Cookeville, TN 38505 USA. NR 10 TC 0 Z9 0 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 MAY PY 2000 VL 61 IS 5 AR 055501 PG 5 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000055 ER PT J AU Khaustov, P Alburger, DE Barnes, PD Bassalleck, B Berdoz, AR Biglan, A Burger, T Carman, DS Chrien, RE Davis, CA Fischer, H Franklin, GB Franz, J Gan, L Ichikawa, A Iijima, T Imai, K Kondo, Y Koran, P Landry, M Lee, L Lowe, J Magahiz, R May, M McCrady, R Meyer, CA Merrill, F Motoba, T Page, SA Paschke, K Pile, PH Quinn, B Ramsay, WD Rusek, A Sawafta, R Schmitt, H Schumacher, RA Stotzer, RW Sutter, R Takeutchi, F van Oers, WTH Yamamoto, K Yamamoto, Y Yosoi, M Zeps, VJ AF Khaustov, P Alburger, DE Barnes, PD Bassalleck, B Berdoz, AR Biglan, A Burger, T Carman, DS Chrien, RE Davis, CA Fischer, H Franklin, GB Franz, J Gan, L Ichikawa, A Iijima, T Imai, K Kondo, Y Koran, P Landry, M Lee, L Lowe, J Magahiz, R May, M McCrady, R Meyer, CA Merrill, F Motoba, T Page, SA Paschke, K Pile, PH Quinn, B Ramsay, WD Rusek, A Sawafta, R Schmitt, H Schumacher, RA Stotzer, RW Sutter, R Takeutchi, F van Oers, WTH Yamamoto, K Yamamoto, Y Yosoi, M Zeps, VJ CA AGS E885 Collaboration TI Evidence of Xi hypernuclear production in the C-12(K-, K+)(Xi)Be-12 reaction SO PHYSICAL REVIEW C LA English DT Article ID K-,K+ REACTION; SEARCH AB The E885 Collaboration utilized the 1.8 GeV/cK(-) beam line at the Alternating Gradient Synchrotron (AGS) to accumulate greater than 10 times the world's existing data sample of (K-,Rf) events on carbon. A total of about 3x10(5) (K-,K+) events were collected and analyzed. drop hypernuclear states are expected to be produced through the reaction K- + C-12-->K+ + Be-12(drop). A signal could also result from direct production of (11)(Lambda)Bei+Lambda without a distinct drop intermediate state. The measured missing-mass spectrum indicates the existence of a signal below the threshold for free drop(-) production that cannot be explained by background or effects of limited resolution. Although the resolution was not sufficient to resolve discrete hypernuclear states, the excess of events in the region of missing mass, kinematically inaccessible in free drop(-) production, can be compared with theoretical predictions for Be-12(drop) production. Reasonable agreement between the data and theory is achieved by assuming a drop-nucleus potential well depth V-0 drop of about 14 MeV within the Woods-Saxon prescription. C1 Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. High Energy Accelerator Res Org, KEK, Tsukuba, Ibaraki 305, Japan. Kyoto Sangyo Univ, Kyoto 603, Japan. Kyoto Univ, Sakyo Ku, Kyoto 606, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Osaka Electrocommun Univ, Osaka 5728530, Japan. TRIUMF, Vancouver, BC V6T 2A3, Canada. Tsuru Univ, Tsuru 4028555, Japan. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Freiburg, D-79104 Freiburg, Germany. Univ Kentucky, Lexington, KY 40507 USA. Univ Manitoba, Winnipeg, MB R3T 2N2, Canada. Univ New Mexico, Albuquerque, NM 87131 USA. RP Khaustov, P (reprint author), Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RI Schumacher, Reinhard/K-6455-2013; Meyer, Curtis/L-3488-2014 OI Schumacher, Reinhard/0000-0002-3860-1827; Meyer, Curtis/0000-0001-7599-3973 NR 10 TC 182 Z9 186 U1 0 U2 1 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 MAY PY 2000 VL 61 IS 5 AR 054603 DI 10.1103/PhysRevC.61.054603 PG 7 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000024 ER PT J AU Zanini, L Corvi, F Postma, H Becvar, F AF Zanini, L Corvi, F Postma, H Becvar, F TI Dependence of the populations of low-energy levels in Ag-108,Ag-110 on the resonance spin and parity SO PHYSICAL REVIEW C LA English DT Article ID NEUTRON RESONANCES; NONCONSERVATION; SPECTROSCOPY; VIOLATION; CD-113; U-238 AB Measurements of prompt gamma rays, following neutron capture in Ag-107 and Ag-109 have been performed at the GELINA facility in the resonance energy region up to about 1 keV. From the intensities of low- and high energy gamma rays the spins of 53 Ag-107 and 78 Ag-109 s- and p-wave resonances have been assigned. These spectroscopic quantities are important for the interpretation of data from parity violation experiments performed by the TRIPLE Collaboration. The intensities of low-energy transitions showed a dependence not only on the spin of the resonance but also on its parity. This effect allows the assignment of the parity of the resonances and may open new perspectives in the study of the gamma decay of the compound nucleus. C1 Commiss European Communities, Joint Res Ctr, Inst Reference Mat & Measurements, B-2440 Geel, Belgium. Delft Univ Technol, NL-2600 GA Delft, Netherlands. Charles Univ Prague, Fac Math & Phys, CZ-18000 Prague 8, Czech Republic. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 35 TC 11 Z9 11 U1 0 U2 1 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 MAY PY 2000 VL 61 IS 5 AR 054616 DI 10.1103/PhysRevC.61.054616 PG 11 WC Physics, Nuclear SC Physics GA 312QB UT WOS:000086953000037 ER PT J AU Adams, T Alton, A Bolton, T Goldman, J Goncharov, M Naples, D Johnson, RA Vakili, M Wu, V Conrad, J Fleming, BT Formaggio, J Koutsoliotas, S Kim, JH McNulty, C Romosan, A Shaevitz, MH Spentzouris, P Stern, EG Vaitaitis, A Zimmerman, ED Bernstein, RH Bugel, L Lamm, MJ Marsh, W Nienaber, P Yu, J de Barbaro, L Buchholz, D Schellman, H Zeller, GP Brau, J Drucker, RB Frey, R Mason, D Avvakumov, S de Barbaro, P Bodek, A Budd, H Harris, DA McFarland, KS Sakumoto, WK Yang, UK AF Adams, T Alton, A Bolton, T Goldman, J Goncharov, M Naples, D Johnson, RA Vakili, M Wu, V Conrad, J Fleming, BT Formaggio, J Koutsoliotas, S Kim, JH McNulty, C Romosan, A Shaevitz, MH Spentzouris, P Stern, EG Vaitaitis, A Zimmerman, ED Bernstein, RH Bugel, L Lamm, MJ Marsh, W Nienaber, P Yu, J de Barbaro, L Buchholz, D Schellman, H Zeller, GP Brau, J Drucker, RB Frey, R Mason, D Avvakumov, S de Barbaro, P Bodek, A Budd, H Harris, DA McFarland, KS Sakumoto, WK Yang, UK TI Evidence for diffractive charm production in nu Fe-mu and nu Fe-mu scattering at the Fermilab Tevatron SO PHYSICAL REVIEW D LA English DT Article ID NEUTRINO; ANTINEUTRINOS; DOMINANCE; PHYSICS; MESONS AB We present evidence for the diffractive processes nu(mu)Fe-->mu(-)D(s)(+)(D*(s))Fe and <(nu)over bar>Fe-mu-->mu(+)D(s)(-)(D*(s))Fe using the Fermilab SSQT neutrino beam and the Lab E neutrino detector. The data are consistent with standard model production of the neutrino trident reactions nu(mu)Fe-->nu(mu)mu(-)mu(+)Fe and <(nu)over bar>Fe-mu--><(nu)over bar>(mu)mu(+)mu(-)Fe. We see no evidence for neutral-current production of J/psi via either diffractive or deep inelastic scattering mechanisms. C1 Kansas State Univ, Manhattan, KS 66506 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Columbia Univ, New York, NY 10027 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Northwestern Univ, Evanston, IL 60208 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Rochester, Rochester, NY 14627 USA. RP Adams, T (reprint author), Kansas State Univ, Manhattan, KS 66506 USA. RI Frey, Raymond/E-2830-2016 OI Frey, Raymond/0000-0003-0341-2636 NR 34 TC 18 Z9 18 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 MAY 1 PY 2000 VL 61 IS 9 AR 092001 DI 10.1103/PhysRevD.61.092001 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 310CZ UT WOS:000086810100003 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlson, J Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chan, AW Chang, PS Chang, FT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Cihangir, S Ciobanu, CI Clark, AG Connolly, A Conway, J Cooper, J Cordelli, M Costanzo, D Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Green, C Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kirk, M Kim, BJ Kim, HS Kim, MJ Kim, SH Kim, YK Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, M Latino, G LeCompte, T Lee, AM Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Taylor, W Tecchio, M Teng, PK Terashi, K Tether, S Theriot, D Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Wu, X Wyss, J Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Zanetti, A Zetti, F Zucchelli, S AF Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bevensee, B Bhatti, A Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlson, J Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chan, AW Chang, PS Chang, FT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Cihangir, S Ciobanu, CI Clark, AG Connolly, A Conway, J Cooper, J Cordelli, M Costanzo, D Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Green, C Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kirk, M Kim, BJ Kim, HS Kim, MJ Kim, SH Kim, YK Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, M Latino, G LeCompte, T Lee, AM Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Rakitine, A Reher, D Reichold, A Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Signorelli, G Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Taylor, W Tecchio, M Teng, PK Terashi, K Tether, S Theriot, D Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Wu, X Wyss, J Yagil, A Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Measurement of the differential dijet mass cross section in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW D LA English DT Article ID = 1.8 TEV; (P)OVER-BAR-P COLLISIONS; PARTON DISTRIBUTIONS; PBARP COLLISIONS; GLOBAL ANALYSIS; SEARCH; EVENTS; ENERGY; CDF AB We present a measurement of the cross section for production of two or more jets as a function of dijet mass, based on an integrated luminosity of 86 pb(-1) collected with the Collider Detector at Fermilab. Our dijet mass spectrum is described within errors by next-to-leading order QCD predictions using CTEQ4HJ parton distributions, and is in good agreement with a similar measurement from the Dempty set experiment. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Cantabria, Inst Fis Cantabria, E-39005 Santander, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Nucl Res Inst, RU-141980 Dubna, Russia. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Kyungpook Natl Univ, Korean Hadron Collider Lab, Taegu 702701, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Sungkyunkwan Univ, Suwon 440746, South Korea. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan. MIT, Cambridge, MA 02139 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Oxford, Oxford OX1 3RH, England. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Affolder, T (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; Prokoshin, Fedor/E-2795-2012 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Prokoshin, Fedor/0000-0001-6389-5399 NR 16 TC 4 Z9 4 U1 0 U2 4 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 MAY 1 PY 2000 VL 61 IS 9 AR 091101 DI 10.1103/PhysRevD.61.091101 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 310CZ UT WOS:000086810100001 ER PT J AU Baer, H Drees, M Paige, F Quintana, P Tata, X AF Baer, H Drees, M Paige, F Quintana, P Tata, X TI Trilepton signal for supersymmetry at the Fermilab Tevatron reexamined SO PHYSICAL REVIEW D LA English DT Article ID CHARGINO-NEUTRALINO PRODUCTION; LARGE TAN-BETA; MINIMAL SUPERGRAVITY; RELIC DENSITY; P(P)OVER-BAR COLLISIONS; ROOT-S=1.8 TEV; DARK-MATTER; COLLIDER; REACH; B->S-GAMMA AB Within a wide class of models, the CERN LEP2 lower limit of 95 GeV on the chargino mass implies gluinos are heavier than similar to 300 GeV. In this case electroweak (W) over tilde(1)(W) over tilde(1) production and (W) over tilde(1)(Z) over tilde(2) production are the dominant supersymmerry (SUSY) processes at the Fermilab Tevatron, and the extensively examined isolated trilepton signal From (W) over tilde(1)(Z) over tilde(2) production assumes an even greater importance. We update our previous calculations of the SUSY reach of luminosity upgrades of the Fermilab Tevatron in this channel incorporating (i) decay matrix elements in the computation of the momenta of leptons from chargino and neutralino decays, (ii) the trilepton background from W*Z* and W*gamma* production which, though neglected in previous analyses, turns out to be the dominant background, and finally, (iii) modified sets of cuts designed to reduce these new backgrounds and increase the range of model parameters for which the signal is observable. We show our improved projections for the reach for SUSY of both the Fermilab Main Injector and the proposed TeV33 upgrade. We also present opposite sign same flavor dilepton invariant mass distributions as well as the p(T) distributions of leptons in SUSY trilepton events, and comment upon how the inclusion of decay matrix elements impacts upon the Tevatron reach, as well as upon the extraction of neutralino masses. C1 Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. Univ Estadual Paulista, IFT, BR-01405900 Sao Paulo, Brazil. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Hawaii, Dept Phys & Astron, Honolulu, HI 96822 USA. RP Baer, H (reprint author), Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. NR 40 TC 65 Z9 65 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 MAY 1 PY 2000 VL 61 IS 9 AR 095007 DI 10.1103/PhysRevD.61.095007 PG 14 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 310CZ UT WOS:000086810100029 ER PT J AU Cobb, JH Marshak, ML Allison, WWM Alner, GJ Ayres, DS Barrett, WL Bode, C Border, PM Brooks, CB Cotton, RJ Courant, H Demuth, DM Fields, TH Gallagher, HR Goodman, MC Gran, R Joffe-Minor, T Kafka, T Kasahara, SMS Leeson, W Litchfield, PJ Longley, NP Mann, WA Milburn, RH Miller, WH Moon, C Mualem, L Napier, A Oliver, WP Pearce, GF Peterson, EA Petyt, DA Price, LE Ruddick, K Sanchez, M Sankey, P Schneps, J Schub, MH Seidlein, R Stassinakis, A Thron, JL Vassiliev, V Villaume, G Wakely, SP West, N Wall, D AF Cobb, JH Marshak, ML Allison, WWM Alner, GJ Ayres, DS Barrett, WL Bode, C Border, PM Brooks, CB Cotton, RJ Courant, H Demuth, DM Fields, TH Gallagher, HR Goodman, MC Gran, R Joffe-Minor, T Kafka, T Kasahara, SMS Leeson, W Litchfield, PJ Longley, NP Mann, WA Milburn, RH Miller, WH Moon, C Mualem, L Napier, A Oliver, WP Pearce, GF Peterson, EA Petyt, DA Price, LE Ruddick, K Sanchez, M Sankey, P Schneps, J Schub, MH Seidlein, R Stassinakis, A Thron, JL Vassiliev, V Villaume, G Wakely, SP West, N Wall, D TI Observation of a shadow of the Moon in the underground muon flux in the Soudan 2 detector SO PHYSICAL REVIEW D LA English DT Article ID COSMIC-RAYS; RANDOM-FIELD; SUN; SIMULATION; CASCADES; MAXIMUM; ARRAY AB A shadow of the Moon, with a statistical significance of 5 sigma, has been observed in the underground muon Aux at a depth of 2090 mwe using the Soudan 2 detector, The angular resolution of the detector is well described by a Gaussian with a sigma less than or equal to 0.3 degrees. The position of the shadow confirms that the alignment of the detector is known to better than 0.15 degrees and has remained stable during ten years of data taking. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Minnesota, Minneapolis, MN 55455 USA. Univ Oxford, Dept Phys, Oxford OX1 3RH, England. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Tufts Univ, Medford, MA 02155 USA. Western Washington State Univ, Bellingham, WA 98225 USA. RP Cobb, JH (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Cotton, Richard/K-2175-2012; Sankey, Jack/K-5072-2012; Sankey, Jack/H-1373-2012 NR 20 TC 0 Z9 0 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 MAY 1 PY 2000 VL 61 IS 9 AR 090002 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 310CZ UT WOS:000086810100004 ER PT J AU Guo, XF Qiu, JW AF Guo, XF Qiu, JW TI Probing quark-gluon correlation functions SO PHYSICAL REVIEW D LA English DT Article ID STRUCTURE-FUNCTION RATIOS; TRANSVERSE-MOMENTUM DISTRIBUTION; NUCLEAR PARTON DISTRIBUTIONS; FRAGMENTATION FUNCTIONS; POWER CORRECTIONS; LEADING ORDER; SMALL-X; DEPENDENCE; QCD; SCATTERING AB We review the applicability of the QCD factorization theorem to multiple scattering in deeply inelastic lepton-nucleus scattering. We show why an A(1/3)-type nuclear enhancement can be calculated consistently in perturbative QCD. We derive the transverse momentum broadening of the leading pions in deeply inelastic lepton-nucleus collisions. We argue that the measurement of such transverse momentum broadening can provide direct information on the multiple-parton correlation functions inside a nucleus. We also estimate the numerical values of the broadening at different values of x(B) and Q(2). C1 Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Guo, XF (reprint author), Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. NR 41 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 1550-7998 EI 1550-2368 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 2000 VL 61 IS 9 AR 096003 DI 10.1103/PhysRevD.61.096003 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 310CZ UT WOS:000086810100036 ER PT J AU Herczeg, P AF Herczeg, P TI P, T-violating electron-nucleon interactions in the R-parity violating minimal supersymmetric standard model SO PHYSICAL REVIEW D LA English DT Article ID CHROMOELECTRIC DIPOLE-MOMENT; PROTON DECAY; THALLIUM FLUORIDE; SIGMA-TERM; CP; COUPLINGS; LIMITS; HG-199; ODD; CONSERVATION AB We show that the present experimental limits on electron-nucleon interactions that violate both parity and time reversal invariance provide new stringent bounds on the imaginary parts of some of the products of the R-parity-violating coupling constants in the R-parity-violating minimal supersymmetric standard model. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Herczeg, P (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 62 TC 14 Z9 14 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 MAY 1 PY 2000 VL 61 IS 9 AR 095010 DI 10.1103/PhysRevD.61.095010 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 310CZ UT WOS:000086810100032 ER PT J AU Hinchliffe, I Paige, FE AF Hinchliffe, I Paige, FE TI Measurements in supergravity models with large tan beta at CERN LHC SO PHYSICAL REVIEW D LA English DT Article ID LARGE HADRON COLLIDER; MINIMAL SUPERGRAVITY; GRAND UNIFICATION; SUPERSYMMETRY; SIGNALS; PHYSICS AB We present an example of a scenario of particle production and decay in supersymmetry models in which the supersymmetry breaking is transmitted to the observable world via gravitational interactions. The case is chosen so that there is a large production of tau leptons in the final state. It is characteristic of large tan beta in that decays into muons and electrons may be suppressed. It is shown that hadronic tan decays can be used to reconstruct final states. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Hinchliffe, I (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 25 TC 71 Z9 71 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 MAY 1 PY 2000 VL 61 IS 9 AR 095011 DI 10.1103/PhysRevD.61.095011 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 310CZ UT WOS:000086810100033 ER PT J AU Plehn, T Rainwater, D Zeppenfeld, D AF Plehn, T Rainwater, D Zeppenfeld, D TI Method for identifying H ->pi pi -> e(+/-)mu(+/-)p(T) at the CERN LHC SO PHYSICAL REVIEW D LA English DT Article ID HEAVY-HIGGS-BOSON; SUPERCONDUCTING SUPER COLLIDER; INTERMEDIATE-MASS HIGGS; WW DECAY MODE; HADRON SUPERCOLLIDERS; STANDARD MODEL; FERMILAB TEVATRON; PAIR PRODUCTION; RAPIDITY GAPS; JETS AB Weak boson fusion promises to be a copious source of intermediate mass Higgs bosons at the CERN LHC. The additional very energetic forward jets in these events provide for powerful background suppression tools. We analyze the subsequent H --> tau tau --> e(+/-)mu(-/+) p(T) decay for Higgs boson masses in the 100-150 GeV range. A parton level analysis of the dominant backgrounds demonstrates that this channel allows the observation of H --> tau tau in a low-background environment, yielding a significant Higgs boson signal with an integrated luminosity of order 60 fb(-1) or less, over most of the mass range. We also restate a no-lose theorem for observation of at least one of the CP-even neutral Higgs bosons in the MSSM, which requires an integrated luminosity of only 40 fb(-1). C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. RP Plehn, T (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. NR 69 TC 117 Z9 117 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 MAY 1 PY 2000 VL 61 IS 9 AR 093005 DI 10.1103/PhysRevD.61.093005 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 310CZ UT WOS:000086810100009 ER PT J AU Yasui, Y AF Yasui, Y TI Technique for loop calculations in non-Abelian gauge theories with applications to a five gluon amplitude SO PHYSICAL REVIEW D LA English DT Article ID BACKGROUND FIELD METHOD; MULTIPLE BREMSSTRAHLUNG; YANG-MILLS; SCATTERING; INTEGRALS AB A powerful tool for calculations in non-Abelian gauge theories is obtained by combining the background field gauge, the helicity basis, and the color decomposition methods. It has reproduced the one-loop calculation of the five-gluon amplitudes in QCD, is applicable to electroweak processes, and extendable to two-loop calculations. C1 Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Yasui, Y (reprint author), Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. EM yasui@bnl.gov NR 46 TC 0 Z9 0 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 MAY 1 PY 2000 VL 61 IS 9 AR 094502 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 310CZ UT WOS:000086810100021 ER PT J AU Sachtjen, ML Carreras, BA Lynch, VE AF Sachtjen, ML Carreras, BA Lynch, VE TI Disturbances in a power transmission system SO PHYSICAL REVIEW E LA English DT Article ID SELF-ORGANIZED CRITICALITY AB A simple model for a power transmission system is presented. In this model, disturbances of all sizes may occur. They are randomly triggered and have the characteristic behavior of avalanches. A single parameter describes the scaling of the avalanche size. This parameter combines a measure of closeness to the maximum load, size of transferred loads during an overloading event, and connectivity of the system. The probability distribution function of the size of the disturbance has power-scaling range with the exponent close to -1. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Sachtjen, ML (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Lynch, Vickie/J-4647-2012 OI Lynch, Vickie/0000-0002-5836-7636 NR 5 TC 139 Z9 142 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2000 VL 61 IS 5 BP 4877 EP 4882 DI 10.1103/PhysRevE.61.4877 PN A PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 314RH UT WOS:000087071000031 ER PT J AU Palmer, BJ Rector, DR AF Palmer, BJ Rector, DR TI Lattice-Boltzmann algorithm for simulating thermal two-phase flow SO PHYSICAL REVIEW E LA English DT Article ID BGK MODELS; LIQUID-GAS; EQUATION AB An algorithm is described for incorporating thermal effects into lattice-Boltzmann simulations of two-phase flow. This algorithm is a combination of a two-distribution model for simulating single-phase thermal flow recently proposed by the authors and the thermodynamically-based model for isothermal two-phase flow of Swift et al. [Phys. Rev. E 54, 5041 (1996)]. The algorithm also corrects a problem with the original single-phase thermal flow model, which described the thermal energy flux as proportional to a gradient of the internal energy instead of being proportional to the gradient of the temperature. For ideal-gas systems, these two descriptions are equivalent but for nonideal systems there is a systematic discrepancy between the original thermal model and classical hydrodynamics. The algorithm is tested on several simple problems. These include formation of a free-standing isothermal thin liquid film, evaporation of a thin liquid film from a heated plate, evaporation of an isolated droplet, and condensation of liquid in a channel. Where possible, the simulations are compared against known analytic results. C1 Pacific NW Lab, Environm & Mol Sci Lab, Richland, WA 99352 USA. RP Palmer, BJ (reprint author), Pacific NW Lab, Environm & Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 21 TC 40 Z9 40 U1 4 U2 17 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2000 VL 61 IS 5 BP 5295 EP 5306 DI 10.1103/PhysRevE.61.5295 PN A PG 12 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 314RH UT WOS:000087071000079 ER PT J AU Ramshaw, JD AF Ramshaw, JD TI Simple model for mixing at accelerated fluid interfaces with shear and compression SO PHYSICAL REVIEW E LA English DT Article ID RAYLEIGH-TAYLOR INSTABILITY; VARIABLE ACCELERATION; TURBULENT AB A simple model was recently described for predicting linear and nonlinear mixing at an unstable planar interface between two fluids of different density subjected to an arbitrary time-dependent variable acceleration history [J. D. Ramshaw, Phys. Rev. E 58, 5834 (1998)]. Here we generalize this model to include the Kelvin Helmholtz (KH) instability resulting from a tangential velocity discontinuity Delta u, as well as the effects of a uniform anisotropic compression or expansion of the mixing layer as a whole. The model consists of a second-order nonlinear ordinary differential equation of motion for the half-width h of the mixing layer. This equation is derived by combining the wavelength renormalization hypothesis used in the earlier model with a suitable expression for the rate of change of the kinetic energy of the mixing layer. The resulting generalized model contains no additional free parameters, and reduces to the previous model in the absence of tangential velocities and compression. It also reduces in the linear regime to the correct linearized stability equation for an accelerated shear layer with compression [J. D. Ramshaw, Phys. Rev. E 61, 1486 (2000)]. For a pure incompressible KH instability in the nonlinear regime, the model predicts that h = eta\Delta u\t, where eta = [alpha(2 - theta)/ root theta(1 - theta)] root rho(1)rho(2)rho/ (rho(1) + rho(2)), and alpha and theta are parameters appearing in the nonlinear Rayleigh-Taylor and Richtmyer-Meshkov growth laws. For equal densities and the same parameter values previously used to match variable-acceleration experimental data, we and eta=0.10, in close agreement with experimental data for free shear layers. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Ramshaw, JD (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-097, Livermore, CA 94551 USA. NR 17 TC 5 Z9 5 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2000 VL 61 IS 5 BP 5339 EP 5344 DI 10.1103/PhysRevE.61.5339 PN A PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 314RH UT WOS:000087071000084 ER PT J AU Blair, D Aranson, IS Crabtree, GW Vinokur, V Tsimring, LS Josserand, C AF Blair, D Aranson, IS Crabtree, GW Vinokur, V Tsimring, LS Josserand, C TI Patterns in thin vibrated granular layers: Interfaces, hexagons, and superoscillons SO PHYSICAL REVIEW E LA English DT Article ID SWIFT-HOHENBERG EQUATION; VERTICAL VIBRATION; WAVE PATTERNS; SURFACE-WAVES; DYNAMICS; MODEL; TRANSITION; SYSTEM; GASES; SAND AB A theoretical and experimental study of patterns in vibrated granular layers is presented. An order parameter model based on the parametric Ginzburg-Landau equation is used to describe strongly nonlinear excitations including hexagons, interfaces between flat antiphase domains, and new localized objects, superoscillons. The experiments confirm the existence of superoscillons and bound states of superoscillons and interfaces. On the basis of the order parameter model we predict analytically and confirm experimentally that additional subharmonic driving results in the controlled motion of interfaces. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif San Diego, Inst Nonlinear Sci, La Jolla, CA 92093 USA. Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Aranson, Igor/I-4060-2013; Blair, Daniel/C-7911-2017 NR 33 TC 31 Z9 32 U1 0 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2000 VL 61 IS 5 BP 5600 EP 5610 DI 10.1103/PhysRevE.61.5600 PN B PG 11 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 314RK UT WOS:000087071200022 ER PT J AU Pacella, D Fournier, KB Zerbini, M Finkenthal, M Mattioli, M May, MJ Goldstein, WH AF Pacella, D Fournier, KB Zerbini, M Finkenthal, M Mattioli, M May, MJ Goldstein, WH TI Temperature and impurity transport studies of heated tokamak plasmas by means of a collisional-radiative model of x-ray emission from Mo30+ to Mo39+ SO PHYSICAL REVIEW E LA English DT Article ID 2L-NL' TRANSITIONS; COMPLEX SPECTRA; SPECTROMETER; ATOMS; MO AB This work presents and interprets, by means of detailed atomic calculations, observations of L-shell (n = 3 --> n = 2) transitions in highly ionized molybdenum, the main intrinsic heavy impurity in the Frascati tokamak upgrade plasmas. These hot plasmas were obtained by additional electron cyclotron resonance heating (ECRH), at the frequency of 140 Ghz, during the current ramp-up phase of the discharge. Injecting 400 kW on axis and 800 kW slightly off axis, the peak central electron temperature reached 8.0 and 7.0 keV, respectively, for a time much longer than the ionization equilibrium time of the molybdenum ions. X-ray emissions from rarely observed high charge states, Mo30+ to Mo39+ have been studied with moderate spectral resolution (lambda/Delta lambda similar to 150) and a time resolution of 5 ms. A sophisticated collisional-radiative model for the study of molybdenum ions in plasmas with electron temperature in the range 4-20 keV is presented. The sensitivity of the x-ray emission to the temperature and to impurity transport processes is discussed. This model has been then used to investigate two different plasma scenarios. In the first regime the ECRH heating occurs on axis during the current ramp up phase, when the magnetic shear is evolving from negative to zero up to the half radius. The spectrum is well reproduced with the molybdenum ions in coronal equilibrium and with a central impurity peaking. In the second regime, at the beginning of the current flat top when magnetic sheer is monotonic and sawtoothing activity is appearing, the lowest charge states (Mo33+ to Mo30+), populated off axis, are affected by anomalous transport and the total molybdenum profile is found to be flat up to the half radius. We conclude with the presentation of "synthetic spectra" computed for even higher temperature plasmas that are expected in future experiments with higher ECRH power input. C1 ENEA Fusione, EURATOM, I-00044 Rome, Italy. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. RP Pacella, D (reprint author), ENEA Fusione, EURATOM, I-00044 Rome, Italy. NR 24 TC 13 Z9 13 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2000 VL 61 IS 5 BP 5701 EP 5709 DI 10.1103/PhysRevE.61.5701 PN B PG 9 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 314RK UT WOS:000087071200037 ER PT J AU de Abajo, FJG AF de Abajo, FJG TI Smith-Purcell radiation emission in aligned nanoparticles SO PHYSICAL REVIEW E LA English DT Article ID INDUCED PHOTON-EMISSION; EXTERNAL ELECTRON-BEAM; ENERGY-LOSS; RELATIVISTIC ELECTRONS; MULTIPLE-SCATTERING; DIELECTRICS; GENERATION; MEDIA; LIGHT; PARTICLES AB Smith-Purcell (SP) radiation produced by interaction of fast electron beams running parallel to strings of nanoparticles is investigated. Results fur the radiation emission probability and electron energy loss spectra using finite and infinite strings of Al and silica spheres are presented. Both of these quantities are obtained by solving Maxwell's equations exactly using a multipole expansion approach. The response of the spheres is described in terms of their local frequency-dependent dielectric functions. In silica, the emission probability is seen to coincide with the energy loss probability within the gap region, where the solid cannot absorb any energy. Large emission rates are predicted fur Al, suggesting its possible application in tunable soft uv light generation. The dependence of the emission on the size of the spheres, the string period, and the electron energy is discussed in detail. Finite size effects are also studied for strings of 1-15 Al spheres. C1 Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP de Abajo, FJG (reprint author), Donostia Int Phys Ctr, Fac Informat, Dept CCIA, San Sebastian, Spain. RI Garcia de Abajo, Javier/A-6095-2009; DONOSTIA INTERNATIONAL PHYSICS CTR., DIPC/C-3171-2014 OI Garcia de Abajo, Javier/0000-0002-4970-4565; NR 40 TC 22 Z9 22 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2000 VL 61 IS 5 BP 5743 EP 5752 DI 10.1103/PhysRevE.61.5743 PN B PG 10 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 314RK UT WOS:000087071200042 ER PT J AU Strasburg, S Davidson, RC AF Strasburg, S Davidson, RC TI Production of halo particles by excitation of collective modes in high-intensity charged particle beams SO PHYSICAL REVIEW E LA English DT Article ID VLASOV-MAXWELL EQUATIONS; FOCUSING CHANNEL; STABILITY PROPERTIES; DOMINATED BEAMS; PROPAGATION; FIELD; SIMULATION AB This paper examines analytically and numerically the effects of self-consistent collective oscillations excited in a high-intensity charged particle beam on the motion of a test particle in the beam core. Even under ideal conditions, assuming a constant transverse focusing force (smooth focusing approximation), and perturbations about a uniform-density, constant radius beam, it is found that collective mode excitations, in combination with the applied focusing force and the equilibrium test fields, can eject particles from the beam core to large radii. Test particle orbits are calculated for collective oscillations with n = 1 and 2 radial mode structure, and an estimate is obtained for the range of initial conditions for which particles will be expelled from the beam interior. Resonances for meridional particles are found to be unimportant, while a class of particles with nonzero angular momentum are found to participate in resonant behavior. Once expelled from the beam, numerical solutions of the orbit equations indicate that Kolmogorov-Arnold-Moser curves, phase space spanning integrals of motion, confine particles within 1.5 times the beam radius for moderately low mode amplitudes, but are successively destabilized for higher amplitudes. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Strasburg, S (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 23 TC 11 Z9 11 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2000 VL 61 IS 5 BP 5753 EP 5766 DI 10.1103/PhysRevE.61.5753 PN B PG 14 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 314RK UT WOS:000087071200043 ER PT J AU Lidorikis, E Soukoulis, CM AF Lidorikis, E Soukoulis, CM TI Pulse-driven switching in one-dimensional nonlinear photonic band gap materials: a numerical study SO PHYSICAL REVIEW E LA English DT Article ID OPTICAL SOLITARY WAVES; MULTILAYER STRUCTURES; PERIODIC STRUCTURES; SOLITONS; SUPERLATTICES; PROPAGATION; BISTABILITY AB We numerically examine the time-dependent properties of nonlinear bistable multilayer structures for constant wave illumination. We find that our system exhibits both steady-state and self-pulsing solutions. In the steady-state regime, we examine the dynamics of driving the system between different transmission states by injecting pulses, and we find optimal pulse parameters. We repeat this work for the case of a linear periodic system with a nonlinear impurity layer. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Lidorikis, E (reprint author), Louisiana State Univ, CCLMS, Baton Rouge, LA 70803 USA. RI Soukoulis, Costas/A-5295-2008 NR 25 TC 19 Z9 31 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 2000 VL 61 IS 5 BP 5825 EP 5829 DI 10.1103/PhysRevE.61.5825 PN B PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 314RK UT WOS:000087071200051 ER PT J AU Formaggio, JA Zimmerman, ED Adams, T Alton, A Avvakumov, S de Barbaro, L de Barbaro, P Bernstein, RH Bodek, A Bolton, T Brau, J Buchholz, D Budd, H Bugel, L Case, S Conrad, JM Drucker, RB Fleming, BT Frey, R Goldman, J Goncharov, M Harris, DA Johnson, RA Kim, JH Koutsoliotas, S Lamm, MJ Marsh, W Mason, D McFarland, KS McNulty, C Naples, D Nienaber, P Romosan, A Sakumoto, WK Schellman, HM Shaevitz, MH Spentzouris, P Stern, EG Vakili, M Vaitaitis, A Wu, V Yang, UK Yu, J Zeller, GP AF Formaggio, JA Zimmerman, ED Adams, T Alton, A Avvakumov, S de Barbaro, L de Barbaro, P Bernstein, RH Bodek, A Bolton, T Brau, J Buchholz, D Budd, H Bugel, L Case, S Conrad, JM Drucker, RB Fleming, BT Frey, R Goldman, J Goncharov, M Harris, DA Johnson, RA Kim, JH Koutsoliotas, S Lamm, MJ Marsh, W Mason, D McFarland, KS McNulty, C Naples, D Nienaber, P Romosan, A Sakumoto, WK Schellman, HM Shaevitz, MH Spentzouris, P Stern, EG Vakili, M Vaitaitis, A Wu, V Yang, UK Yu, J Zeller, GP TI Search for a 33.9 MeV/c(2) neutral particle in pion decay SO PHYSICAL REVIEW LETTERS LA English DT Article ID HEAVY-LEPTONS; NEUTRINOS; BEAM AB The E815 (NnTeV) neutrino experiment has performed a search for a 33.9 MeV/c(2) weakly interacting neutral particle produced in pion decay. Such a particle may be responsible for an anomaly in the timing distribution of neutrino interactions in the KARMEN experiment. E815 has searched for this particle's decays in an instrumented decay region; no evidence for this particle was found. The search is sensitive to pion branching ratios as low as 10(-13). C1 Columbia Univ, New York, NY 10027 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Fermilab Astrophys Ctr, Batavia, IL 60510 USA. Kansas State Univ, Manhattan, KS 66506 USA. Northwestern Univ, Evanston, IL 60201 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Rochester, Rochester, NY 14627 USA. RP Formaggio, JA (reprint author), Columbia Univ, New York, NY 10027 USA. RI Frey, Raymond/E-2830-2016 OI Frey, Raymond/0000-0003-0341-2636 NR 16 TC 17 Z9 17 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 MAY 1 PY 2000 VL 84 IS 18 BP 4043 EP 4046 DI 10.1103/PhysRevLett.84.4043 PG 4 WC Physics, Multidisciplinary SC Physics GA 309YN UT WOS:000086797300007 ER PT J AU Airapetian, A Akopov, N Amarian, M Aschenauer, EC Avakian, H Avakian, R Avetissian, A Avetissian, E Bains, B Baumgarten, C Beckmann, M Belostotski, S Belz, JE Benisch, T Bernreuther, S Bianchi, N Blouw, J Bottcher, H Borissov, A Bouwhuis, M Brack, J Brauksiepe, S Braun, B Bray, B Brons, S Bruckner, W Brull, A Bruins, EEW Bulten, HJ Capitani, GP Carter, P Chumney, P Cisbani, E Court, GR Dalpiaz, PF De Sanctis, E De Schepper, D Devitsin, E Huberts, PKAD Di Nezza, P Duren, M Dvoredsky, A Elbakian, G Ely, J Fantoni, A Fechtchenko, A Ferstl, M Fiedler, K Filippone, BW Fischer, H Fox, B Franz, J Frullani, S Funk, MA Garber, Y Gao, H Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Golendukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Guidal, M Gute, A Gyurjyan, V Haas, JP Haeberli, W Hansen, JO Hartig, M Hasch, D Hausser, O Heinsius, FH Henderson, R Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A Kaiser, R Kinney, E Kisselev, A Kitching, P Kobayashi, H Koch, N Konigsmann, K Kolstein, M Kolster, H Korotkov, V Korsch, W Kozlov, V Kramer, LH Krivokhijine, VG Kurisuno, M Kyle, G Lachnit, W Lenisa, P Lorenzon, W Makins, NCR Martens, FK Martin, JW Masoli, F Mateos, A McAndrew, M McIlhany, K McKeown, RD Meissner, F Menden, F Metz, A Meyners, N Mikloukho, O Miller, CA Miller, MA Milner, R Most, A Muccifora, V Mussa, R Nagaitsev, A Naryshkin, Y Nathan, AM Neunreither, F Niczyporuk, M Nowak, WD Nupieri, M Oganessyan, KA O'Neill, TG Openshaw, R Ouyang, J Owen, BR Papavassiliou, V Pate, SF Pitt, M Potashov, S Potterveld, DH Rakness, G Reali, A Redwine, R Reolon, AR Ristinen, R Rith, K Rossi, P Rudnitsky, S Ruh, M Ryckbosch, D Sakemi, Y Savin, I Scarlett, C Schafer, A Schmidt, F Schmitt, H Schnell, G Schuler, KP Schwind, A Seibert, J Shibata, TA Shibatani, K Shin, T Shutov, V Simani, C Simon, A Sinram, K Slavich, P Spengos, M Steffens, E Stenger, J Stewart, J Stoesslein, U Sutter, M Tallini, H Taroian, S Terkulov, A Teryaev, O Thomas, E Tipton, B Tytgat, M Urciuoli, GM van den Brand, JFJ van der Steenhoven, G van de Vyver, R van Hunen, JJ Vetterli, MC Vikhrov, V Vincter, MG Visser, J Volk, E Wander, W Wendland, J Williamson, SE Wise, T Woller, K Yoneyama, S Zohrabian, H AF Airapetian, A Akopov, N Amarian, M Aschenauer, EC Avakian, H Avakian, R Avetissian, A Avetissian, E Bains, B Baumgarten, C Beckmann, M Belostotski, S Belz, JE Benisch, T Bernreuther, S Bianchi, N Blouw, J Bottcher, H Borissov, A Bouwhuis, M Brack, J Brauksiepe, S Braun, B Bray, B Brons, S Bruckner, W Brull, A Bruins, EEW Bulten, HJ Capitani, GP Carter, P Chumney, P Cisbani, E Court, GR Dalpiaz, PF De Sanctis, E De Schepper, D Devitsin, E Huberts, PKAD Di Nezza, P Duren, M Dvoredsky, A Elbakian, G Ely, J Fantoni, A Fechtchenko, A Ferstl, M Fiedler, K Filippone, BW Fischer, H Fox, B Franz, J Frullani, S Funk, MA Garber, Y Gao, H Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Golendukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Guidal, M Gute, A Gyurjyan, V Haas, JP Haeberli, W Hansen, JO Hartig, M Hasch, D Hausser, O Heinsius, FH Henderson, R Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A Kaiser, R Kinney, E Kisselev, A Kitching, P Kobayashi, H Koch, N Konigsmann, K Kolstein, M Kolster, H Korotkov, V Korsch, W Kozlov, V Kramer, LH Krivokhijine, VG Kurisuno, M Kyle, G Lachnit, W Lenisa, P Lorenzon, W Makins, NCR Martens, FK Martin, JW Masoli, F Mateos, A McAndrew, M McIlhany, K McKeown, RD Meissner, F Menden, F Metz, A Meyners, N Mikloukho, O Miller, CA Miller, MA Milner, R Most, A Muccifora, V Mussa, R Nagaitsev, A Naryshkin, Y Nathan, AM Neunreither, F Niczyporuk, M Nowak, WD Nupieri, M Oganessyan, KA O'Neill, TG Openshaw, R Ouyang, J Owen, BR Papavassiliou, V Pate, SF Pitt, M Potashov, S Potterveld, DH Rakness, G Reali, A Redwine, R Reolon, AR Ristinen, R Rith, K Rossi, P Rudnitsky, S Ruh, M Ryckbosch, D Sakemi, Y Savin, I Scarlett, C Schafer, A Schmidt, F Schmitt, H Schnell, G Schuler, KP Schwind, A Seibert, J Shibata, TA Shibatani, K Shin, T Shutov, V Simani, C Simon, A Sinram, K Slavich, P Spengos, M Steffens, E Stenger, J Stewart, J Stoesslein, U Sutter, M Tallini, H Taroian, S Terkulov, A Teryaev, O Thomas, E Tipton, B Tytgat, M Urciuoli, GM van den Brand, JFJ van der Steenhoven, G van de Vyver, R van Hunen, JJ Vetterli, MC Vikhrov, V Vincter, MG Visser, J Volk, E Wander, W Wendland, J Williamson, SE Wise, T Woller, K Yoneyama, S Zohrabian, H CA HERMES Collaboration TI Evidence for a single-spin azimuthal asymmetry in semi-inclusive pion electroproduction SO PHYSICAL REVIEW LETTERS LA English DT Article ID FRAGMENTATION FUNCTIONS; ANALYZING POWER; DISTRIBUTIONS; LEPTOPRODUCTION; NUCLEONS; BEAM AB Single-spin asymmetries for semi-inclusive pion production in deep-inelastic scattering have been measured for the first time. A significant target-spin asymmetry of the distribution in the azimuthal angle phi of the pion relative to the lepton scattering plane was formed for pi(+) electroproduction on a longitudinally polarized hydrogen target. The corresponding analyzing power in the sin phi moment of the cross section is 0.022 +/- 0.005 +/- 0.003. This result can be interpreted as the effect of terms in the cross section involving chiral-odd spin distribution functions in combination with a chiral-odd fragmentation function that is sensitive to the transverse polarization of the fragmenting quark. C1 Yerevan Phys Inst, Yerevan 375036, Armenia. Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. CALTECH, WK Kellogg Radiat Lab, Pasadena, CA 91125 USA. Univ Colorado, Nucl Phys Lab, Boulder, CO 80309 USA. DESY, D-22603 Hamburg, Germany. DESY, D-15738 Zeuthen, Germany. Joint Inst Nucl Res, Dubna 141980, Russia. Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany. Univ Ferrara, Dipartimento Fis, I-44100 Ferrara, Italy. Univ Ferrara, Ist Nazl Fis Nucl, Sez Ferrara, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Florida Int Univ, Dept Phys, Miami, FL 33199 USA. Univ Freiburg, Fak Phys, D-79104 Freiburg, Germany. Univ Ghent, Dept Subatom & Radiat Phys, B-9000 Ghent, Belgium. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Univ Liverpool, Dept Phys, Liverpool L69 7ZE, Merseyside, England. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. PN Lebedev Phys Inst, Moscow 117924, Russia. Univ Munich, Sekt Phys, D-85748 Garching, Germany. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. NIKHEF H, NL-1009 DB Amsterdam, Netherlands. Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany. Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. Ist Super Sanita, Phys Lab, I-00161 Rome, Italy. Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. TRIUMF, Vancouver, BC V6T 2A3, Canada. Tokyo Inst Technol, Dept Phys, Tokyo 1528551, Japan. Free Univ Amsterdam, Dept Phys & Astron, NL-1081 HV Amsterdam, Netherlands. RP Yerevan Phys Inst, Yerevan 375036, Armenia. RI Gao, Haiyan/G-2589-2011; Gavrilov, Gennady/C-6260-2013; Holt, Roy/E-5803-2011; Kozlov, Valentin/M-8000-2015; Terkulov, Adel/M-8581-2015; Cisbani, Evaristo/C-9249-2011; OI Cisbani, Evaristo/0000-0002-6774-8473; Mussa, Roberto/0000-0002-0294-9071 NR 29 TC 336 Z9 336 U1 1 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 MAY 1 PY 2000 VL 84 IS 18 BP 4047 EP 4051 DI 10.1103/PhysRevLett.84.4047 PG 5 WC Physics, Multidisciplinary SC Physics GA 309YN UT WOS:000086797300008 ER PT J AU Fischer, SM Balamuth, DP Hausladen, PA Lister, CJ Carpenter, MP Seweryniak, D Schwartz, J AF Fischer, SM Balamuth, DP Hausladen, PA Lister, CJ Carpenter, MP Seweryniak, D Schwartz, J TI Evidence for collective oblate rotation in N = Z Se-68 SO PHYSICAL REVIEW LETTERS LA English DT Article ID NUCLEI; IDENTIFICATION; TRIAXIALITY; COEXISTENCE; SE-72 AB A gamma-ray spectroscopic measurement of the N = Z nucleus Se-68 has been made Following the C-12(Ni-58.2n) reaction at 185 and 220 MeV using Gammasphere and the Argonne Fragment Mass Analyzer. Despite a very low production cross section of 200(50) mu b, two distinct rotational bands were found: the ground state band consistent with oblate collective rotation, and an excited band consistent with prolate rotation. These observations support long-standing predictions that nuclear ground states with substantial oblate (beta(2) similar to -0.3) deformation should exist in this region. C1 De Paul Univ, Dept Phys, Chicago, IL 60614 USA. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Fischer, SM (reprint author), De Paul Univ, Dept Phys, Chicago, IL 60614 USA. RI Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 18 TC 90 Z9 93 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 MAY 1 PY 2000 VL 84 IS 18 BP 4064 EP 4067 DI 10.1103/PhysRevLett.84.4064 PG 4 WC Physics, Multidisciplinary SC Physics GA 309YN UT WOS:000086797300012 ER PT J AU Groenenboom, GC Mas, EM Bukowski, R Szalewicz, K Wormer, PES van der Avoird, A AF Groenenboom, GC Mas, EM Bukowski, R Szalewicz, K Wormer, PES van der Avoird, A TI Water pair and three-body potential of spectroscopic quality from ab initio calculations SO PHYSICAL REVIEW LETTERS LA English DT Article ID TERAHERTZ LASER SPECTROSCOPY; ADAPTED PERTURBATION-THEORY; COUPLED 6-DIMENSIONAL CALCULATIONS; ROTATION-TUNNELING SPECTRUM; FAR-INFRARED SPECTRUM; QUANTITATIVE CHARACTERIZATION; THEORETICAL-ANALYSIS; TORSIONAL MANIFOLD; TRIMER ISOTOPOMERS; SYMMETRY AB zWe present the first pair plus three-body potential of water from ab initio calculations that quantitatively reproduces the experimental far-infrared spectra of the water dimer and trimer. The dimer spectrum was obtained from the pair potential through rigorous six-dimensional quantum calculations of the vibration-rotation-tunneling levels. The three-body interactions, together with the pair potential, produce an accurate representation of the hydrogen bond torsional levels of the water trimer. C1 Univ Nijmegen, NSR Ctr, Inst Theoret Chem, NL-6525 ED Nijmegen, Netherlands. Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Warsaw, Dept Chem, Quantum Chem Lab, PL-02093 Warsaw, Poland. RP Groenenboom, GC (reprint author), Univ Nijmegen, NSR Ctr, Inst Theoret Chem, NL-6525 ED Nijmegen, Netherlands. RI Groenenboom, Gerrit/F-9692-2015; OI Groenenboom, Gerrit/0000-0002-0920-3707 NR 29 TC 88 Z9 88 U1 0 U2 13 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 MAY 1 PY 2000 VL 84 IS 18 BP 4072 EP 4075 DI 10.1103/PhysRevLett.84.4072 PG 4 WC Physics, Multidisciplinary SC Physics GA 309YN UT WOS:000086797300014 ER PT J AU Yoo, CS Cynn, H Soderlind, P Iota, V AF Yoo, CS Cynn, H Soderlind, P Iota, V TI New beta(fcc)-cobalt to 210 GPa SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-PRESSURE; TRANSITION-METALS; CRYSTAL-STRUCTURE; X-RAY; PHASE-DIAGRAM; EARTH-CORE; IN-SITU; IRON; STATE; TEMPERATURE AB We report a new phase transition in cobalt from the magnetic epsilon(hcp) to a beta(fcc) phase, likely nonmagnetic, at 105 GPa. It occurs martensitically in an extended pressure region between 105 and 150 GPa without any apparent volume change. The fee phase of Co is in systematic accordance with the id and 5d counterparts. The pressure-volume isotherm of beta-Co resembles those of alpha(fcc)-Ni and epsilon(hcp)-Fe within 1%. The phase diagram of cobalt suggests that the fee stability increases with increasing occupancy of d-band electrons from Fe to Co to Ni. C1 Univ Calif Lawrence Livermore Natl Lab, Phys Directorate, H Div, Livermore, CA 94551 USA. RP Yoo, CS (reprint author), Univ Calif Lawrence Livermore Natl Lab, Phys Directorate, H Div, Livermore, CA 94551 USA. NR 25 TC 81 Z9 81 U1 0 U2 9 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 MAY 1 PY 2000 VL 84 IS 18 BP 4132 EP 4135 DI 10.1103/PhysRevLett.84.4132 PG 4 WC Physics, Multidisciplinary SC Physics GA 309YN UT WOS:000086797300029 ER PT J AU Menoni, CS Miao, L Patel, D Mic'ic, OI Nozik, AJ AF Menoni, CS Miao, L Patel, D Mic'ic, OI Nozik, AJ TI Three-dimensional confinement in the conduction band structure of InP SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUANTUM DOTS; PRESSURE; TRANSITION; WIRES; FILMS; STATE; WELLS; GAP AB Strong quantum confinement in InP is observed to significantly reduce the separation between the direct and indirect conduction band states. The effects of three-dimensional confinement are investigated by tailoring the initial separation between conduction band states using quantum dots (QDs) of different sizes and hydrostatic pressure. Analyses of the QD emission spectra show that the X-1c states are lowest in energy at pressures of similar to 6 GPa, much lower than in the bulk. The transition to the X-1c states can be explained by either a sequence of Gamma-L and L-X crossings, or by the crossover between strongly coupled Gamma and X states. C1 Colorado State Univ, Dept Elect & Comp Engn, Ft Collins, CO 80523 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Menoni, CS (reprint author), Colorado State Univ, Dept Elect & Comp Engn, Ft Collins, CO 80523 USA. RI Menoni, Carmen/A-3775-2008; Menoni, Carmen/B-4989-2011; Nozik, Arthur/A-1481-2012; Nozik, Arthur/P-2641-2016 NR 16 TC 18 Z9 19 U1 0 U2 6 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 MAY 1 PY 2000 VL 84 IS 18 BP 4168 EP 4171 DI 10.1103/PhysRevLett.84.4168 PG 4 WC Physics, Multidisciplinary SC Physics GA 309YN UT WOS:000086797300038 ER PT J AU Canpolat, M Mourant, JR AF Canpolat, M Mourant, JR TI High-angle scattering events strongly affect light collection in clinically relevant measurement geometries for light transport through tissue SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID SOURCE-DETECTOR SEPARATIONS; DIFFUSION-APPROXIMATION; ABSORPTION-COEFFICIENTS; OPTICAL-PROPERTIES; FREQUENCY-DOMAIN; TURBID MEDIA; REFLECTANCE; CELLS; SPECTROSCOPY; DIAGNOSTICS AB Measurement of light transport in tissue has the potential to be an inexpensive and practical tool for non-invasive tissue diagnosis in medical applications because it can provide information on both morphological and biochemical properties. To capitalize on the potential of light transport as a diagnostic tool, an understanding of what information can be gleaned from light transport measurements is needed. We present data concerning the sensitivity of light transport measurements, made in clinically relevant geometries, to scattering properties. The intensity of the backscattered light at small source-detector separations is shown to be sensitive to the phase function, and furthermore the collected light intensity is found to be correlated with the amount of high-angle scattering in the medium. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. RP Canpolat, M (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, MS E535, Los Alamos, NM 87545 USA. RI Tewatia, Dinesh/D-5897-2012 FU NCI NIH HHS [CA71898, R01 CA071898] NR 27 TC 24 Z9 25 U1 2 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD MAY PY 2000 VL 45 IS 5 BP 1127 EP 1140 DI 10.1088/0031-9155/45/5/304 PG 14 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 319CG UT WOS:000087321900005 PM 10843095 ER PT J AU Manuilskiy, I Lee, WW AF Manuilskiy, I Lee, WW TI The split-weight particle simulation scheme for plasmas SO PHYSICS OF PLASMAS LA English DT Article ID GYROKINETIC SIMULATION; DRIFT INSTABILITIES AB An efficient numerical method for treating electrons in magnetized plasmas has been developed. The scheme, which is based on the perturbative (delta f) gyrokinetic particle simulation, splits the particle electron responses into adiabatic and nonadiabatic parts. The former is incorporated into the gyrokinetic Poisson's equation, while the latter is calculated dynamically with the aid of the charge conservation equation. The new scheme affords us the possibility of suppressing unwanted high-frequency oscillations and, in the meantime, relaxing the Courant condition for the thermal particles moving in the parallel direction. It is most useful for studying low-frequency phenomena in plasmas. As an example, one-dimensional drift wave simulation has been carried out using the scheme and the results are presented in this paper. This methodology can easily be generalized to problems in three-dimensional toroidal geometry, as well as those in unmagnetized plasmas. (C) 2000 American Institute of Physics. [S1070-664X(00)00405-5]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Manuilskiy, I (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 11 TC 45 Z9 45 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1381 EP 1385 DI 10.1063/1.873955 PN 1 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 304XY UT WOS:000086510800008 ER PT J AU Sanchez, E Hidalgo, C Lopez-Bruna, D Garcia-Cortes, I Balbin, R Pedrosa, MA van Milligen, B Riccardi, C Chiodini, G Bleuel, J Endler, M Carreras, BA Newman, DE AF Sanchez, E Hidalgo, C Lopez-Bruna, D Garcia-Cortes, I Balbin, R Pedrosa, MA van Milligen, B Riccardi, C Chiodini, G Bleuel, J Endler, M Carreras, BA Newman, DE TI Statistical characterization of fluctuation wave forms in the boundary region of fusion and nonfusion plasmas SO PHYSICS OF PLASMAS LA English DT Article ID SELF-ORGANIZED CRITICALITY; EDGE TURBULENCE; COHERENT STRUCTURES; TOROIDAL PLASMA; TRANSPORT; CONFINEMENT; OPERATION; DYNAMICS; LAYER AB The statistical properties of plasma fluctuations have been investigated in the plasma boundary region of fusion (tokamaks and stellarators) and nonfusion plasmas. Fluctuations in ion saturation current and floating potential have a near-Gaussian character in the proximity of the velocity shear layer (r(sh)). However, fluctuations deviate from a Gaussian distribution when moving inside of the plasma edge (r < r(sh)) or into the scrape-off layer region (r > r(sh)). Furthermore, fluctuations show sporadic pulses that are asymmetric in time. The present analysis shows a coupling of those pulses and the averaged flow in the shear layer region. (C) 2000 American Institute of Physics. [S1070-664X(00)00805-3]. C1 Asoc Euratim Ciemat, Madrid 28040, Spain. Univ Milan Bicocca, I-20126 Milan, Italy. INFM, I-20126 Milan, Italy. IPP Garching, EURATOM Assoc, D-85740 Garching, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Alaska, Fairbanks, AK 99775 USA. RP Sanchez, E (reprint author), Asoc Euratim Ciemat, Madrid 28040, Spain. RI Sanchez, Edilberto/D-4620-2009; van Milligen, Boudewijn/H-5121-2015; Lopez Bruna, Daniel/L-6539-2014; Garcia-Cortes, Isabel/H-3341-2015; Balbin, Rosa/F-8210-2010; Hidalgo, Carlos/H-6109-2015; OI Sanchez, Edilberto/0000-0003-1062-7870; van Milligen, Boudewijn/0000-0001-5344-6274; Garcia-Cortes, Isabel/0000-0002-5223-391X; Balbin, Rosa/0000-0001-5231-1300; RICCARDI, CLAUDIA/0000-0002-3983-5414 NR 28 TC 82 Z9 82 U1 3 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1408 EP 1416 PN 1 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XY UT WOS:000086510800011 ER PT J AU Alman, DA Ruzic, DN Brooks, JN AF Alman, DA Ruzic, DN Brooks, JN TI A hydrocarbon reaction model for low temperature hydrogen plasmas and an application to the Joint European Torus SO PHYSICS OF PLASMAS LA English DT Article ID IONIZATION CROSS-SECTIONS; DISSOCIATIVE RECOMBINATION; IMPACT AB A model of collisional processes of hydrocarbons in hydrogen plasmas has been developed to aid in computer modeling efforts relevant to plasma-surface interactions. It includes 16 molecules (CH up to CH4, C2H to C2H6, and C3H to C3H6) and four reaction types (electron impact ionization/dissociative ionization, electron impact dissociation, proton impact charge exchange, and dissociative recombination). Experimental reaction rates or cross sections have been compiled, and estimates have been made for cases where these are not available. The proton impact charge exchange reaction rates are calculated from a theoretical model using molecular polarizabilities. Dissociative recombination rates are described by the equation A/T-B where parameter A is fit using polarizabilities and B is estimated from known reaction rates. The electron impact ionization and dissociation cross sections are fit to known graphs using four parameters: threshold energy, maximum value of the cross section, energy at the maximum, and a constant for the exponential decay as energy increases. The model has recently been used in an analysis of the Joint European Torus [P. H. Rebut, R. J. Bickerton, and B. E. Keen, Nucl. Fusion 25, 1011 (1985)] MARK II carbon inner divertor using the WBC Monte Carlo impurity transport code. The updated version of WBC, which includes the full set of hydrocarbon reactions, helps to explain an observed asymmetry in carbon deposition near the divertor. (C) 2000 American Institute of Physics. [S1070-664X(00)00505-X]. C1 Univ Illinois, Dept Nucl Plasma & Radiol Engn, Urbana, IL 61801 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Alman, DA (reprint author), Univ Illinois, Dept Nucl Plasma & Radiol Engn, Urbana, IL 61801 USA. NR 23 TC 75 Z9 75 U1 1 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1421 EP 1432 DI 10.1063/1.873960 PN 1 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 304XY UT WOS:000086510800013 ER PT J AU Gorelenkov, NN Cheng, CZ Fu, GY Kaye, S White, R Gorelenkova, MV AF Gorelenkov, NN Cheng, CZ Fu, GY Kaye, S White, R Gorelenkova, MV TI Fast particle destabilization of toroidicity-induced Alfven eigenmodes in the National Spherical Torus Experiment SO PHYSICS OF PLASMAS LA English DT Article ID TOROIDAL PLASMAS; STABILITY AB Toroidicity-induced Alfven eigenmode (TAE) stability in the National Spherical Torus Experiment (NSTX) [S. M. Kaye, M. Ono, Y.-K. M. Peng , Fusion Technol. 36, 16 (1999)] is analyzed using the improved NOVA-K code [N. N. Gorelenkov, C. Z. Cheng, and G. Y. Fu, Phys. Plasmas 6, 2802 (1999)], which includes finite orbit width and Larmor radius effects and is able to predict the saturation amplitude for the mode using the quasilinear theory. A broad spectrum of unstable global TAEs with different toroidal mode numbers is predicted. Due to the strong poloidal field and the presence of the magnetic well in NSTX, better particle confinement in the presence of TAEs in comparison with tokamaks is illustrated making use of the ORBIT code [R. B. White and M. S. Chance, Phys. Fluids 27, 2455 (1984)]. (C) 2000 American Institute of Physics. [S1070-664X(00)00705-9]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. TRINITI, Troitsk 142092, Moscow Region, Russia. RP Gorelenkov, NN (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI White, Roscoe/D-1773-2013; Cheng, Chio/K-1005-2014 OI White, Roscoe/0000-0002-4239-2685; NR 16 TC 8 Z9 8 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1433 EP 1436 DI 10.1063/1.873961 PN 1 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 304XY UT WOS:000086510800014 ER PT J AU Peterson, RR Lindman, EL Delamater, ND Magelssen, GR AF Peterson, RR Lindman, EL Delamater, ND Magelssen, GR TI Computer simulations of laser hot spots and implosion symmetry kiniform phase plate experiments on Nova SO PHYSICS OF PLASMAS LA English DT Article ID PLASMAS; INTERPENETRATION AB LASNEX computer code simulations have been performed for radiation symmetry experiments on the Nova laser with vacuum and gas-filled hohlraum targets [R. L. Kauffman , Phys. Plasmas 5, 1927 (1998)]. In previous experiments with unsmoothed laser beams, the symmetry was substantially shifted by deflection of the laser beams. In these experiments, laser beams have been smoothed with Kiniform Phase Plates in an attempt to remove deflection of the beams. The experiments have shown that this smoothing significantly improves the agreement with LASNEX calculations of implosion symmetry. The images of laser produced hot spots on the inside of the hohlraum case have been found to differ from LASNEX calculations, suggesting that some beam deflection or self-focusing may still be present or that emission from interpenetrating plasmas is an important component of the images. The measured neutron yields are in good agreement with simulations for vacuum hohlraums but are far different for gas-filled hohlraums. (C) 2000 American Institute of Physics. [S1070-664X(00)02505-2]. C1 Univ Wisconsin, Fus Technol Inst, Madison, WI 53706 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Peterson, RR (reprint author), Univ Wisconsin, Fus Technol Inst, 1500 Engn Dr, Madison, WI 53706 USA. NR 14 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1544 EP 1554 DI 10.1063/1.873974 PN 1 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 304XY UT WOS:000086510800027 ER PT J AU Delamater, ND Lindman, EL Magelssen, GR Failor, BH Murphy, TJ Hauer, AA Gobby, P Moore, JB Gomez, V Gifford, K Kauffman, RL Landen, OL Hammel, BA Glendinning, G Powers, LV Suter, LJ Dixit, S Peterson, RR Richard, AL AF Delamater, ND Lindman, EL Magelssen, GR Failor, BH Murphy, TJ Hauer, AA Gobby, P Moore, JB Gomez, V Gifford, K Kauffman, RL Landen, OL Hammel, BA Glendinning, G Powers, LV Suter, LJ Dixit, S Peterson, RR Richard, AL TI Observation of reduced beam deflection using smoothed beams in gas-filled hohlraum symmetry experiments at Nova SO PHYSICS OF PLASMAS LA English DT Article ID LASER; PERFORMANCE; SYSTEM; FUSION; FLOW AB Execution and modeling of drive symmetry experiments in gas-filled hohlraums have been pursued to provide both a better understanding of radiation symmetry in such hohlraums and to verify the accuracy of the design tools which are used to predict target performance for the National Ignition Facility (NIF) [J. Lindl, Phys. Plasmas 2, 3933 (1995)]. In this paper, the results of a series of drive symmetry experiments using gas-filled hohlraums at the Nova laser facility [C. Bibeau , Appl. Opt. 31, 5799 (1992)] at Lawrence Livermore National Laboratory are presented. A very important element of these experiments was the use of kineform phase plates (KPP) to smooth the Nova beams. The effect of smoothing the ten Nova beams with KPP phase plates is to remove most of the beam bending which had been observed previously, leaving a residual bending of only 1.5 degrees, equivalent to a 35 mu m pointing offset at the hohlraum wall. The results show that the symmetry variation with pointing of implosions in gas-filled hohlraums is consistent with time integrated modeling. (C) 2000 American Institute of Physics. [S1070-664X(00)02405-8]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Wisconsin, Madison, WI 53706 USA. CEA, DIF, F-91680 Bruyeres Le Chatel, France. RP Delamater, ND (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Murphy, Thomas/F-3101-2014 OI Murphy, Thomas/0000-0002-6137-9873 NR 15 TC 19 Z9 21 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1609 EP 1613 DI 10.1063/1.873982 PN 1 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 304XY UT WOS:000086510800036 ER PT J AU Remington, BA Drake, RP Takabe, H Arnett, D AF Remington, BA Drake, RP Takabe, H Arnett, D TI A review of astrophysics experiments on intense lasers SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID DRIVEN SHOCK-WAVES; EXPANDING PHOTOSPHERE METHOD; TYCHO SUPERNOVA REMNANT; DENSITY FOAM TARGETS; GAMMA-RAY BURSTS; II SUPERNOVAE; CYGNUS LOOP; SN 1993J; X-RAY; ABSORPTION-MEASUREMENTS AB Astrophysics has traditionally been pursued at astronomical observatories and on theorists' computers. Observations record images from space, and theoretical models are developed to explain the observations. A component often missing has been the ability to test theories and models in an experimental setting where the initial and final states are well characterized. Intense lasers are now being used to recreate aspects of astrophysical phenomena in the laboratory, allowing the creation of experimental testbeds where theory and modeling can be quantitatively tested against data. We describe here several areas of astrophysics-supernovae, supernova remnants, gamma-ray bursts, and giant planets-where laser experiments are under development to test our understanding of these phenomena. (C) 2000 American Institute of Physics. [S1070-664X(00)97605-5]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Osaka Univ, Osaka, Japan. Univ Arizona, Tucson, AZ 85721 USA. RP Remington, BA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Drake, R Paul/I-9218-2012 OI Drake, R Paul/0000-0002-5450-9844 NR 138 TC 130 Z9 132 U1 2 U2 14 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1641 EP 1652 DI 10.1063/1.874046 PN 2 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000004 ER PT J AU Velikovich, AL Dahlburg, JP Schmitt, AJ Gardner, JH Phillips, L Cochran, FL Chong, YK Dimonte, G Metzler, N AF Velikovich, AL Dahlburg, JP Schmitt, AJ Gardner, JH Phillips, L Cochran, FL Chong, YK Dimonte, G Metzler, N TI Richtmyer-Meshkov-like instabilities and early-time perturbation growth in laser targets and Z-pinch loads SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WA SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; INDUCED SPATIAL INCOHERENCE; TAILORED DENSITY PROFILES; START-UP PHASE; SHOCK-WAVE; RAREFACTION WAVE; DRIVEN; MODEL; STABILITY; IMPLOSION AB The classical Richtmyer-Meshkov (RM) instability develops when a planar shock wave interacts with a corrugated interface between two different fluids. A larger family of so-called RM-like hydrodynamic interfacial instabilities is discussed. All of these feature a perturbation growth at an interface, which is driven mainly by vorticity, either initially deposited at the interface or supplied by external sources. The inertial confinement fusion relevant physical conditions that give rise to the RM-like instabilities range from the early-time phase of conventional ablative laser acceleration to collisions of plasma shells (like components of nested-wire-arrays, double-gas-puff Z-pinch loads, supernovae ejecta and interstellar gas). In the laser ablation case, numerous additional factors are involved: the mass flow through the front, thermal conduction in the corona, and an external perturbation drive (laser imprint), which leads to a full stabilization of perturbation growth. In contrast with the classical RM case, mass perturbations can exhibit decaying oscillations rather than a linear growth. It is shown how the early-time perturbation behavior could be controlled by tailoring the density profile of a laser target or a Z-pinch load, to diminish the total mass perturbation seed for the Rayleigh-Taylor instability development. (C) 2000 American Institute of Physics. [S1070-664X(00)93305-6]. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. USN, Res Lab, Computat Phys & Fluid Dynam Lab, Washington, DC 20375 USA. Berkeley Res Associates Inc, Springfield, VA 22150 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Nucl Res Ctr Negev, Dept Phys, IL-84190 Beer Sheva, Israel. Sci Applicat Int Corp, Mclean, VA 22150 USA. RP USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. RI Velikovich, Alexander/B-1113-2009 NR 66 TC 49 Z9 49 U1 1 U2 10 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 MAY PY 2000 VL 7 IS 5 BP 1662 EP 1671 DI 10.1063/1.873986 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000006 ER PT J AU Peng, YKM AF Peng, YKM TI The physics of spherical torus plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID ASPECT-RATIO TOKAMAK; MAGNETOHYDRODYNAMIC TEARING MODES; COAXIAL HELICITY INJECTION; HIGH-BETA PLASMAS; TRANSPORT BARRIERS; HALO CURRENTS; SUSTAINMENT; LIMITS AB Broad and important progress in plasma tests, theory, new experiments, and future visions of the spherical torus (ST, or very low aspect ratio tokamaks) have recently emerged. These have substantially improved our understanding of the potential properties of the ST plasmas, since the preliminary calculation of the ST magnetohydrodynamic equilibria more than a decade ago. Exciting data have been obtained from concept exploration level ST experiments of modest capabilities (with major radii up to 35 cm), making important scientific contributions to toroidal confinement in general. The results have helped approval and construction of new and/or more powerful ST experiments, and stimulated an increasing number of theoretical calculations of interest to magnetic fusion energy. Utilizing the broad knowledge base from the successful tokamak and advanced tokamak research, a wide range of new ST physics features has been suggested. These properties of the ST plasma will be tested at the 1 MA level with major radius up to similar to 80 cm in the new proof of principle devices National Spherical Torus Experiment (NSTX, U.S.) [M. Peng , European Conf. Abst. 22C, 451 (1998); S. M. Kaye , Fusion Technol. 36, 16 (1999); M. Ono , "Exploration of Spherical Torus Physics in the NSTX Device," 17th IAEA Fusion Energy Conf., paper IAEA-CN-69/ICP/01 (R), Yokohama, Japan (1998)], Mega Ampere Spherical Tokamak (MAST, U.K.) [A. C. Darke , Fusion Technol. 1, 799 (1995); Q. W. Morris , Proc. Int. Workshop on ST (Ioffe Inst., St. Petersburg, 1997), Vol. 1, p. 290], and Globus-M (R.F.) [V. K. Gusev , European Conf. Abst. 22C, 576 (1998)], which have just started full experimental operation. New concept exploration experiments, such as Pegasus (University of Wisconsin) [R. Fonck and the PEGASUS Team, Bull. Am. Phys. Soc. 44, 267 (1999)], Helicity Injected Tokamak-II (HIT-II, University of Washington) [T. R. Jarboe , Phys. Plasmas 5, 1807 (1998)], and Current Drive Experiment-Upgrade (CDX-U, Princeton Plasma Physics Laboratory) [M. Ono , Proceedings of the 16th International Conference on Fusion Energy (IAEA, Vienna, 1997), Vol. 2, p. 71] and other experiments in Japan and Brazil, etc., present additional opportunities for important progress. This tutorial paper summarizes our understanding and projections of the physics of the ST plasmas, the investigation of which will hopefully bring new enthusiasm and advancements for fusion energy science research in the U.S. and the world. (C) 2000 American Institute of Physics. [S1070-664X(00)97905-9]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Peng, YKM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 67 TC 50 Z9 51 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1681 EP 1692 DI 10.1063/1.874048 PN 2 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000008 ER PT J AU Barnes, DC Schauer, MM Umstadter, KR Chacon, L Miley, G AF Barnes, DC Schauer, MM Umstadter, KR Chacon, L Miley, G TI Electron equilibrium and confinement in a modified Penning trap and its application to Penning fusion SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID FOCUS AB The Penning fusion concept is described. Recent theoretical work on eliminating limitations on thermonuclear gain (Q) associated with ion-ion collisions is reviewed. A critical issue identified is the demonstration of the desired spherical electron configuration. Constraints on the electron distribution function are derived. A small combined trap (majority electrons), PFX-I (Penning Fusion eXperiment-Ions) has been constructed to study these issues. PFX-I is described. Two diagnostics described for electrons are destructive dumping of trapped electrons and noninvasive optical detection of impact induced fluorescence. Initial results of PFX-I operation at applied voltages V-0 up to 2 kV and magnetic fields B up to 1.14 T are described. Electron equilibrium is found to be consistent with trap filling to the space charge limit, with inventory proportional to V-0 and independent of B. Electron confinement times range from 1 to 10 ms and are determined by neutral pressure. These results are interpreted and future directions sketched. (C) 2000 American Institute of Physics. [S1070-664X(00)93505-5]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Illinois, Fus Studies Lab, Urbana, IL 61801 USA. RP Barnes, DC (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 25 TC 16 Z9 17 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1693 EP 1701 DI 10.1063/1.873987 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000009 ER PT J AU del-Castillo-Negrete, D AF del-Castillo-Negrete, D TI Chaotic transport in zonal flows in analogous geophysical and plasma systems SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID PRESERVING NONTWIST MAPS; ANOMALOUS DIFFUSION; ROSSBY WAVES; PARTICLE-TRANSPORT; GEOSTROPHIC FLOW; REVERSED SHEAR; LEVY FLIGHTS; INSTABILITY; TRANSITION; TURBULENCE AB Zonal flows occur naturally in geophysical fluids. Important examples include Jupiter's zonal flows, large scale jets in the earth's stratosphere, and oceanic jets like the Gulf Stream. These zonal flows create transport barriers that have a crucial influence on mixing and confinement. On the other hand, zonal flows have also been observed in fusion plasmas and their role in the reduction of transport has been widely recognized. Based on the analogy between Rossby waves in quasigeostrophic flows and drift waves in magnetically confined plasmas, recent models and laboratory experiments developed for studying transport in geophysical fluid dynamics are discussed in the context of plasma physics. The flows considered are not turbulent and are dominated by large scale coherent structures which we describe with simple deterministic Hamiltonian models that exhibit chaotic transport. Two transport problems are studied: the role of drift/Rossby waves in the destruction of transport barriers, and the statistics of test particle motion. It is shown that non-monotonic zonal flows close to marginal stability typically exhibit robust transport barriers at the peak velocity where the shear locally vanishes. Also, it is shown that the trapping effect of vortices combined with the zonal flows gives rise to anomalous diffusion and Levy (non-Gaussian) statistics. The models are compared with fluid laboratory experiment. (C) 2000 American Institute of Physics. [S1070-664X(00)95805-1]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP del-Castillo-Negrete, D (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. OI del-Castillo-Negrete, Diego/0000-0001-7183-801X NR 45 TC 39 Z9 39 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1702 EP 1711 DI 10.1063/1.873988 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000010 ER PT J AU Sanbonmatsu, KY Vu, HX Bezzerides, B DuBois, DF AF Sanbonmatsu, KY Vu, HX Bezzerides, B DuBois, DF TI The effect of kinetic processes on Langmuir turbulence SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID STIMULATED RAMAN-SCATTERING; PLASMA TURBULENCE; DIFFUSION; IONOSPHERE; WAVES AB Kinetic processes are shown to be crucial in determining the saturation level of stimulated Raman scattering for regimes relevant to NOVA [Campbell et al., Fusion Technol. 21, 1344 (1992)] and the National Ignition Facility [Lindl, Phys. Plasmas 2, 3933 (1995)]. To investigate these kinetic effects, the Zakharov, quasilinear-Zakharov, and reduced-description particle-in-cell simulation models are compared in the test case of a uniformly driven plasma. Good agreement is observed between all three simulation methods for relatively low primary Langmuir wave numbers (k(1)lambda(De) similar to 0.1) in weakly driven regimes. In the strongly driven case, quasilinear diffusion provides an important correction to the Landau damping rate, producing saturation levels in agreement with reduced-description particle-in-cell simulations, in contrast to pure Zakharov simulations, which overestimate the saturation significantly. At higher k(1)lambda(De) similar to 0.25, both the quasilinear-Zakharov and pure Zakharov models fail. In this regime, the autocorrelation time of the Langmuir wave spectrum is much larger than the quasilinear diffusion time, causing the quasilinear diffusion approximation to break down. (C) 2000 American Institute of Physics. [S1070-664X(00)94305-2]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sanbonmatsu, KY (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 27 TC 23 Z9 23 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1723 EP 1731 DI 10.1063/1.873991 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000013 ER PT J AU Yamada, M Ji, HT Hsu, S Carter, T Kulsrud, R Trintchouk, F AF Yamada, M Ji, HT Hsu, S Carter, T Kulsrud, R Trintchouk, F TI Experimental investigation of the neutral sheet profile during magnetic reconnection SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID LABORATORY PLASMA AB During magnetic reconnection, a "neutral sheet" current is induced, heating the plasma. The resultant plasma thermal pressure forms a stationary equilibrium with the opposing magnetic fields. The reconnection layer profile holds significant clues about the physical mechanisms which control reconnection. In the Magnetic Reconnection Experiment [M. Yamada et al., Phys. Plasmas 4, 1936 (1997)], a quasi steady-state and axisymmetric neutral sheet profile has been measured precisely using a magnetic probe array with spatial resolution equal to one quarter of the ion gyro-radius. It was found that the reconnecting field profile fits well with a Harris-type profile [E. G. Harris, Il Nuovo Cimento 23, 115 (1962)], B(x) similar to tanh(x/delta). This agreement is remarkable since the Harris theory does not take into account reconnection and associated electric fields and dissipation. An explanation for this agreement is presented. The sheet thickness delta is found to be similar to 0.4 times the ion skin depth, which agrees with a generalized Harris theory incorporating nonisothermal electron and ion temperatures and finite electric field. The detailed study of additional local features of the reconnection region is also presented. (C) 2000 American Institute of Physics. [S1070-664X(00)95505-8]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Yamada, M (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Carter, Troy/E-7090-2010; Yamada, Masaaki/D-7824-2015; OI Carter, Troy/0000-0002-5741-0495; Yamada, Masaaki/0000-0003-4996-1649; Hsu, Scott/0000-0002-6737-4934 NR 19 TC 66 Z9 66 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1781 EP 1787 DI 10.1063/1.873999 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000021 ER PT J AU Fu, GY Ku, LP Cooper, WA Hirshman, SH Monticello, DA Redi, MH Reiman, A Sanchez, R Spong, DA AF Fu, GY Ku, LP Cooper, WA Hirshman, SH Monticello, DA Redi, MH Reiman, A Sanchez, R Spong, DA TI Magnetohydrodynamics stability of compact stellarators SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID PLASMAS; TOKAMAK; MODES; SHEAR AB Recent stability results of external kink modes and vertical modes in compact stellarators are presented. The vertical mode is found to be stabilized by externally generated poloidal flux. A simple stability criterion is derived in the limit of large aspect ratio and constant current density. For a wall at infinite distance from the plasma, the amount of external flux needed for stabilization is given by F-i = (kappa(2) - kappa)/(kappa(2) + 1), where kappa is the axisymmetric elongation and F-i is the fraction of the external rotational transform. A systematic parameter study shows that the external kink mode in a quasiaxisymmetric stellarator (QAS) can be stabilized at high beta (similar to 5%) without a conducting wall by magnetic shear via three-dimensional (3D) shaping. It is found that external kinks are driven by both parallel current and pressure gradient. The pressure contributes significantly to the overall drive through the curvature term and the Pfirsch-Schluter current. (C) 2000 American Institute of Physics. [S1070-664X(00)91005-X]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. EPFL, CRPP, CH-1015 Lausanne, Switzerland. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. Univ Carlos III Madrid, Madrid, Spain. RP Fu, GY (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Sanchez, Raul/C-2328-2008; Spong, Donald/C-6887-2012 OI Spong, Donald/0000-0003-2370-1873 NR 25 TC 10 Z9 10 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1809 EP 1815 DI 10.1063/1.874002 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000025 ER PT J AU Fasoli, A Borba, D Breizman, B Gormezano, C Heeter, RF Juan, A Mantsinen, M Sharapov, S Testa, D AF Fasoli, A Borba, D Breizman, B Gormezano, C Heeter, RF Juan, A Mantsinen, M Sharapov, S Testa, D TI Fast particles-wave interaction in the Alfven frequency range on the Joint European Torus tokamak SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID DEUTERIUM-TRITIUM PLASMAS; FUSION TEST REACTOR; DIII-D; EIGENMODES; INSTABILITIES; TOROIDICITY; EXCITATION; EVOLUTION; TRANSPORT; JT-60U AB Wave-particle interaction phenomena in the Alfven Eigenmode (AE) frequency range are investigated at the Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)] using active and passive diagnostic methods. Fast particles are generated by neutral beam injection, ion cyclotron resonance heating, and fusion reactions. External antennas are used to excite stable AEs and measure fast particle drive and damping separately. Comparisons with numerical calculations lead to an identification of the different damping mechanisms. The use of the active AE diagnostic system to generate control signals based on the proximity to marginal stability limits for AE and low-frequency magnetohydrodynamic (MHD) modes is explored. Signatures of the different nonlinear regimes of fast particle driven AE instabilities predicted by theory are found in the measured spectra. The diagnostic use of AE measurements to get information both on the plasma bulk and the fast particle distribution is assessed. (C) 2000 American Institute of Physics. [S1070-664X(00)91505-2]. C1 MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, PSFC, Cambridge, MA 02139 USA. Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Inst Super Tecn, EURATOM Assoc, P-1096 Lisbon, Portugal. Univ Texas, Inst Fus Studies, Austin, TX 78712 USA. Royal Inst Technol, Alfven Lab, SE-10044 Stockholm, Sweden. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Fasoli, A (reprint author), MIT, Dept Phys, 175 Albany St, Cambridge, MA 02139 USA. RI Borba, Duarte/K-6148-2015; Mantsinen, Mervi/B-8023-2016 OI Borba, Duarte/0000-0001-5305-2857; Mantsinen, Mervi/0000-0001-9927-835X NR 39 TC 29 Z9 29 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1816 EP 1824 DI 10.1063/1.874003 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000026 ER PT J AU Lin, Z Hahm, TS Lee, WW Tang, WM White, RB AF Lin, Z Hahm, TS Lee, WW Tang, WM White, RB TI Gyrokinetic simulations in general geometry and applications to collisional damping of zonal flows SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID TEMPERATURE-GRADIENT TURBULENCE; PARTICLE-SIMULATION; POLOIDAL ROTATION; TOKAMAK PLASMAS; TRANSPORT; DYNAMICS; DRIVEN; MODEL; EQUATIONS; WAVES AB A fully three-dimensional gyrokinetic particle code using magnetic coordinates for general geometry has been developed and applied to the investigation of zonal flows dynamics in toroidal ion-temperature-gradient turbulence. Full torus simulation results support the important conclusion that turbulence-driven zonal flows significantly reduce the turbulent transport. Linear collisionless simulations for damping of an initial poloidal flow perturbation exhibit an asymptotic residual flow. The collisional damping of this residual causes the dependence of ion thermal transport on the ion-ion collision frequency, even in regimes where the instabilities are collisionless. (C) 2000 American Institute of Physics. [S1070-664X(00)94705-0]. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Lin, Z (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI White, Roscoe/D-1773-2013 OI White, Roscoe/0000-0002-4239-2685 NR 42 TC 58 Z9 58 U1 0 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1857 EP 1862 DI 10.1063/1.874008 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000031 ER PT J AU McKee, GR Murakami, M Boedo, JA Brooks, NH Burrell, KH Ernst, DR Fonck, RJ Jackson, GL Jakubowski, M La Haye, RJ Messiaen, AM Ongena, J Rettig, CL Rice, BW Rost, C Staebler, GM Sydora, RD Thomas, DM Unterberg, B Wade, MR West, WP AF McKee, GR Murakami, M Boedo, JA Brooks, NH Burrell, KH Ernst, DR Fonck, RJ Jackson, GL Jakubowski, M La Haye, RJ Messiaen, AM Ongena, J Rettig, CL Rice, BW Rost, C Staebler, GM Sydora, RD Thomas, DM Unterberg, B Wade, MR West, WP TI Impurity-induced turbulence suppression and reduced transport in the DIII-D tokamak SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WA SP Amer Phys Soc, Div Plasma Phys ID MAGNETIC CONFINEMENT DEVICES; I MODE-STABILITY; SHEAR; PLASMA; DISCHARGES; DENSITY AB Long wavelength turbulence as well as heat and momentum transport are significantly reduced in the DIII-D tokamak [Plasma Physics and Controlled Nuclear Fusion Research (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159] as a result of neon seeding of a low confinement mode negative central shear discharge. Correspondingly, the energy confinement time increases by up to 80%. Fully saturated turbulence measurements near rho = 0.7 (rho = r/a) in the wave number range 0.1 less than or equal to k(perpendicular to)rho(s) less than or equal to 0.6, obtained with beam emission spectroscopy, exhibit a significant reduction of fluctuation power after neon injection. Fluctuation measurements obtained with far infrared scattering also show a reduction of turbulence in the core, while the Langmuir probe array measures reduced particle flux in the edge and scrape-off layer. Gyrokinetic linear stability simulations of these plasmas are qualitatively consistent, showing a reduction in the growth rate of ion temperature gradient driven modes for 0 < k(perpendicular to)rho(s) less than or equal to 1.4, and nonlinear gyrokinetic simulations show a reduced saturated density fluctuation amplitude. The measured omega(ExB) shearing rate increased at rho = 0.7, suggesting that impurity-induced growth rate reduction is acting synergistically with omega(ExB) shear to decrease turbulence and reduce anomalous transport. (C) 2000 American Institute of Physics. [S1070-664X(00)92805-2]. C1 Gen Atom Co, San Diego, CA 92186 USA. Univ Wisconsin, Madison, WI USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Forschungszentrum Julich, Julich, Germany. Univ Calif Los Angeles, Los Angeles, CA USA. Lawrence Livermore Natl Lab, Livermore, CA USA. MIT, Cambridge, MA 02139 USA. Univ Alberta, Edmonton, AB, Canada. RP McKee, GR (reprint author), Gen Atom Co, San Diego, CA 92186 USA. EM mckee@fusion.gat.com RI Ernst, Darin/A-1487-2010; OI Ernst, Darin/0000-0002-9577-2809; Unterberg, Bernhard/0000-0003-0866-957X NR 30 TC 43 Z9 43 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1870 EP 1877 DI 10.1063/1.874010 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000033 ER PT J AU Baylor, LR Jernigan, TC Combs, SK Houlberg, WA Murakami, M Gohil, P Burrell, KH Greenfield, CM Groebner, RJ Hsieh, CL La Haye, RJ Parks, PB Staebler, GM Schmidt, GL Ernst, DR Synakowski, EJ Porkolab, M AF Baylor, LR Jernigan, TC Combs, SK Houlberg, WA Murakami, M Gohil, P Burrell, KH Greenfield, CM Groebner, RJ Hsieh, CL La Haye, RJ Parks, PB Staebler, GM Schmidt, GL Ernst, DR Synakowski, EJ Porkolab, M CA DIII-D Team TI Improved core fueling with high field side pellet injection in the DIII-D tokamak SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID MAGNETIC SHEAR; ASPECT RATIO; CONFINEMENT; JET; DISCHARGES; PROFILES; TRANSPORT; PLASMAS; DENSITY; TFTR AB The capability to inject deuterium pellets from the magnetic high field side (HFS) has been added to the DIII-D tokamak [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)]. It is observed that pellets injected from the HFS lead to deeper mass deposition than identical pellets injected from the outside midplane, in spite of a factor of 4 lower pellet speed. HFS injected pellets have been used to generate peaked density profile plasmas [peaking factor (n(e)(0)/[n(e)]) in excess of 3] that develop internal transport barriers when centrally heated with neutral beam injection. The transport barriers are formed in conditions where T-e similar to T-i and q(0) is above unity. The peaked density profiles, characteristic of the internal transport barrier, persist for several energy confinement times. The pellets are also used to investigate transport barrier physics and modify plasma edge conditions. Transitions from L- to H-mode have been triggered by pellets, effectively lowering the H-mode threshold power by 2.4 MW. Pellets injected into H-mode plasmas are found to trigger edge localized modes (ELMs). ELMs triggered from the low field side (LFS) outside midplane injected pellets are of significantly longer duration than from HFS injected pellets. (C) 2000 American Institute of Physics. [S1070-664X(00)94105-3]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Gen Atom Co, San Diego, CA USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. MIT, Cambridge, MA 02139 USA. RP Baylor, LR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Ernst, Darin/A-1487-2010 OI Ernst, Darin/0000-0002-9577-2809 NR 38 TC 86 Z9 91 U1 5 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1878 EP 1885 DI 10.1063/1.874011 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000034 ER PT J AU Bonoli, PT Brambilla, M Nelson-Melby, E Phillips, CK Porkolab, M Schilling, G Taylor, G Wukitch, SJ Boivin, RL Boswell, CJ Fiore, CL Gangadhara, S Goetz, J Granetz, R Greenwald, M Hubbard, AE Hutchinson, IH In, Y Irby, J LaBombard, B Lipschultz, B Marmar, E Mazurenko, A Nachtrieb, R Pappas, D Pitcher, CS Reardon, J Rice, J Rowan, WL Snipes, JA Takase, Y Terry, J Wolfe, SM AF Bonoli, PT Brambilla, M Nelson-Melby, E Phillips, CK Porkolab, M Schilling, G Taylor, G Wukitch, SJ Boivin, RL Boswell, CJ Fiore, CL Gangadhara, S Goetz, J Granetz, R Greenwald, M Hubbard, AE Hutchinson, IH In, Y Irby, J LaBombard, B Lipschultz, B Marmar, E Mazurenko, A Nachtrieb, R Pappas, D Pitcher, CS Reardon, J Rice, J Rowan, WL Snipes, JA Takase, Y Terry, J Wolfe, SM TI Mode conversion electron heating in Alcator C-Mod: Theory and experiment SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WA SP Amer Phys Soc, Div Plasma Phys ID ION-BERNSTEIN WAVES; CURRENT DRIVE; CYCLOTRON RANGE; TOKAMAK; PLASMAS; PROPAGATION; FREQUENCIES AB Localized electron heating [full width at half maximum of Delta(r/a) approximate to 0.2] by mode converted ion Bernstein waves (IBW) has been observed in the Alcator C-Mod tokamak [I. H. Hutchinson , Phys. Plasmas 1, 1511 (1994)]. These experiments were performed in D(He-3) plasmas at high magnetic field (B-0 = 7.9 T), high-plasma density (n(e0) greater than or equal to 1.5 x 10(20) m(-3)), and for 0.05 less than or equal to n(He-3)/n(e) less than or equal to 0.30. Electron heating profiles of the mode converted IBW were measured using a break in slope analysis of the electron temperature versus time in the presence of rf (radio frequency) modulation. The peak position of electron heating was found to be well-correlated with He-3 concentration, in agreement with the predictions of cold plasma theory. Recently, a toroidal full-wave ion cyclotron range of frequencies (ICRF) code TORIC [M. Brambilla, Nucl. Fusion 38, 1805 (1998)] was modified to include the effects of IBW electron Landau damping at (k(perpendicular to)rho(i))(2) much greater than 1, This model was used in combination with a 1D (one-dimensional) integral wave equation code METS [D. N. Smithe et al., Radio Frequency Power in Plasmas, AIP Conf. Proc. 403 (1997), p. 367] to analyze these experiments. Model predictions were found to be in qualitative and in some instances quantitative agreement with experimental measurements. A model for mode conversion current drive (MCCD) has also been developed which combines a toroidal full wave code with an adjoint evaluation of the ICRF current drive efficiency. Predictions for off-axis MCCD in C-Mod have been made using this model and will be described. (C) 2000 American Institute of Physics. [S1070-664X(00)94205-8]. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Max Planck Inst Plasma Phys, D-85748 Garching, Germany. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Texas, Fus Res Ctr, Austin, TX 78712 USA. Univ Tokyo, Dept Phys, Tokyo 113, Japan. RP Bonoli, PT (reprint author), MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. EM bonoli@psfc.mit.edu RI Hutchinson, Ian/D-1136-2009; Lipschultz, Bruce/J-7726-2012; OI Hutchinson, Ian/0000-0003-4276-6576; Lipschultz, Bruce/0000-0001-5968-3684; Greenwald, Martin/0000-0002-4438-729X NR 27 TC 22 Z9 22 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 MAY PY 2000 VL 7 IS 5 BP 1886 EP 1893 DI 10.1063/1.874012 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000035 ER PT J AU Neilson, GH Reiman, AH Zarnstorff, MC Brooks, A Fu, GY Goldston, RJ Ku, LP Lin, Z Majeski, R Monticello, DA Mynick, H Pomphrey, N Redi, MH Reiersen, WT Schmidt, JA Hirshman, SP Lyon, JF Berry, LA Nelson, BE Sanchez, R Spong, DA Boozer, AH Miner, WH Valanju, PM Cooper, WA Drevlak, M Merkel, P Nuehrenberg, C AF Neilson, GH Reiman, AH Zarnstorff, MC Brooks, A Fu, GY Goldston, RJ Ku, LP Lin, Z Majeski, R Monticello, DA Mynick, H Pomphrey, N Redi, MH Reiersen, WT Schmidt, JA Hirshman, SP Lyon, JF Berry, LA Nelson, BE Sanchez, R Spong, DA Boozer, AH Miner, WH Valanju, PM Cooper, WA Drevlak, M Merkel, P Nuehrenberg, C TI Physics issues in the design of high-beta, low-aspect-ratio stellarator experiments SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID ENERGY CONFINEMENT; TRANSPORT; EQUILIBRIA; DEVICES AB High-beta, low-aspect-ratio ("compact") stellarators are promising solutions to the problem of developing a magnetic plasma configuration for magnetic fusion power plants that can be sustained in steady state without disrupting. These concepts combine features of stellarators and advanced tokamaks and have aspect ratios similar to those of tokamaks (2-4). They are based on computed plasma configurations that are shaped in three dimensions to provide desired stability and transport properties. Experiments are planned as part of a program to develop this concept. A beta = 4% quasi-axisymmetric plasma configuration has been evaluated for the National Compact Stellarator Experiment (NCSX). It has a substantial bootstrap current and is shaped to stabilize ballooning, external kink, vertical, and neoclassical tearing modes without feedback or close-fitting conductors. Quasi-omnigeneous plasma configurations stable to ballooning modes at beta = 4% have been evaluated for the Quasi-Omnigeneous Stellarator (QOS) experiment. These equilibria have relatively low bootstrap currents and are insensitive to changes in beta. Coil configurations have been calculated that reconstruct these plasma configurations, preserving their important physics properties. Theory- and experiment-based confinement analyses are used to evaluate the technical capabilities needed to reach target plasma conditions. The physics basis for these complementary experiments is described. (C) 2000 American Institute of Physics. [S1070-664X(00)94905-X]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Columbia Univ, Dept Appl Phys, New York, NY 10027 USA. Univ Texas, Austin, TX 78712 USA. Ecole Polytech Fed Lausanne, Lausanne, Switzerland. Max Planck Inst Plasma Phys, D-17491 Greifswald, Germany. RP Neilson, GH (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Sanchez, Raul/C-2328-2008; pomphrey, neil/G-4405-2010; Spong, Donald/C-6887-2012 OI Spong, Donald/0000-0003-2370-1873 NR 37 TC 45 Z9 45 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1911 EP 1918 DI 10.1063/1.874015 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000038 ER PT J AU Boivin, RL Goetz, JA Hubbard, AE Hughes, JW Hutchinson, IH Irby, JH LaBombard, B Marmar, ES Mossessian, D Pitcher, CS Terry, JL Carreras, BA Owen, LW AF Boivin, RL Goetz, JA Hubbard, AE Hughes, JW Hutchinson, IH Irby, JH LaBombard, B Marmar, ES Mossessian, D Pitcher, CS Terry, JL Carreras, BA Owen, LW TI Effects of neutral particles on edge dynamics in Alcator C-Mod plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID DIII-D; CONFINEMENT; RECOMBINATION; TRANSITION; TRANSPORT; TOKAMAKS AB Neutral particle densities and energy losses have been measured in the Alcator C-Mod tokamak [Hutchinson et al., Phys. Plasmas 1, 1511 (1994)]. Their effect on the formation and evolution of the edge barrier which accompanies the enhanced confinement regime are discussed. The neutrals can enter the edge dynamics through the particle, momentum, and energy balance. Neutral densities of up to 5 x 10(16) m(-3) have been measured in the edge barrier region. Neutrals enter the local dynamics around most of the periphery, not just at the X-point. High resolution measurements of the ionization profile have been obtained for the region near the separatrix. The profile shifts inside the separatrix as the plasma is making a transition from low-to high-mode confinement (H-mode) regimes, partly accounting for the dramatic rise in edge density. The measured neutral density is large enough to affect the bulk ion momentum by charge exchange, and thereby introduces a negative radial electric field at the edge. At the same time, significant edge heat flux, carried by the neutrals, contributes to the measured power loss. At very high edge densities, this loss mechanism could contribute to quenching H-modes. (C) 2000 American Institute of Physics. [S1070-664X(00)95005-5]. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Boivin, RL (reprint author), MIT, Plasma Sci & Fus Ctr, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Hutchinson, Ian/D-1136-2009 OI Hutchinson, Ian/0000-0003-4276-6576 NR 26 TC 43 Z9 43 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1919 EP 1926 DI 10.1063/1.874016 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000039 ER PT J AU Douglas, MR Deeney, C Spielman, RB Coverdale, CA Roderick, NF Peterson, DL AF Douglas, MR Deeney, C Spielman, RB Coverdale, CA Roderick, NF Peterson, DL TI Implosion dynamics of long-pulse wire array Z pinches SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID POWER AB Recent improvements in Z-pinch wire array load design at Sandia National Laboratories have led to a substantial increase in pinch performance as measured by radiated powers of up to 280 TW in 4 ns and 1.8 MJ of total radiated energy. Next generation, higher-current machines will allow for larger mass arrays and comparable or higher velocity implosions to be reached, possibly extending these results. As the current is pushed above 20 MA, a conventional machine design based on a 100 ns implosion time results in higher voltages, hence higher cost and power flow risk. Another approach, which shifts the risk to the load configuration, is to increase the implosion time to minimize the voltage. This approach is being investigated in a series of experimental campaigns on the Saturn [C. Deeney et al., Phys. Plasmas 6, 3576 (1999)] and Z [R. B. Spielman et al., Phys. Plasmas 5, 2105 (1998)] machines. In this paper, both experimental and two-dimensional computational modeling of the first long implosion time Z experiments will be presented. The experimental data shows broader pulses, lower powers, and larger pinch diameters compared to the corresponding short pulse data. By employing a nested array configuration, the pinch diameter was reduced by 50% with a corresponding increase in power of > 30%. Numerical simulations suggest that load velocity is the dominating mechanism behind these results. (C) 2000 American Institute of Physics. [S1070-664X(00)96005-1]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Albuquerque, NM 87102 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Douglas, MR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 27 TC 18 Z9 19 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1935 EP 1944 DI 10.1063/1.874018 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000041 ER PT J AU Xu, XQ Cohen, RH Rognlien, TD Myra, JR AF Xu, XQ Cohen, RH Rognlien, TD Myra, JR TI Low-to-high confinement transition simulations in divertor geometry SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID H-MODE TRANSITION; TURBULENCE; TRANSPORT; TOKAMAKS; PLASMA; PARAMETERS; EQUATIONS; DYNAMICS; SYSTEMS; SHEAR AB Recent results are presented for turbulence in tokamak boundary plasmas and its relationship to the low-to-high confinement (L-H) transition in a realistic divertor geometry. These results are obtained from a three-dimensional (3D) nonlocal electromagnetic turbulence code, which models the boundary plasma using fluid equations for plasma vorticity, density, electron and ion temperatures and parallel momenta. With sources added in the core-edge region and sinks in the scrape-off layer (SOL), the code follows the self-consistent profile evolution together with turbulence. Under DIII-D [Luxon , International Conference on Plasma Physics and Controlled Nuclear Fusion (International Atomic Energy Agency, Vienna, 1986), p. 159] tokamak L-mode conditions, the dominant source of turbulence is pressure-gradient-driven resistive X-point modes. These modes are electromagnetic and curvature-driven at the outside mid-plane region but become electrostatic near X-points due to magnetic shear and collisionality. Classical resistive ballooning modes at high toroidal mode number, n, coexist with these modes but are sub-dominant. Results indicate that, as the power is increased, these modes are stabilized by increased turbulence-generated velocity shear, resulting in an abrupt suppression of high-n turbulence and the formation of a pedestal in density and temperature, as is characteristic of the H-mode transition. The sensitivity of the boundary turbulence to the direction of the toroidal field B-t is discussed. [S1070-664X(00)96405-X]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Lodestar Res Corp, Boulder, CO 80301 USA. RP Xu, XQ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 33 TC 124 Z9 125 U1 0 U2 17 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1951 EP 1958 DI 10.1063/1.874044 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000043 ER PT J AU Parks, PB Sessions, WD Baylor, LR AF Parks, PB Sessions, WD Baylor, LR TI Radial displacement of pellet ablation material in tokamaks due to the grad-B effect SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID INJECTION; PLASMA; FIELD; CLOUD AB During pellet injection in tokamaks, a rapid movement of pellet ablation substance towards the low-field or outward major radius R direction is observed, favoring pellet injection from the high-field side in order to promote deeper fuel penetration. The motion has been attributed to a vertical curvature and del B drift current induced inside the ionized ablated material by the 1/R toroidal field variation. The uncompensated vertical drift current inside the weakly diamagnetic (beta < 0.1) ablation cloud will cause charge separation at the boundary. The resulting electrostatic field induces the ExB drift to the large-R side of the torus. The calculated fuel penetration depth is consistent with inside launched pellet experiments on the DIII-D tokamak [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)]. The dependence of the penetration depth with plasma parameters suggests that low velocity inside launched pellets may provide a unique solution to the refueling problem in larger and hotter machines of the future. (C) 2000 American Institute of Physics. [S1070-664X(00)97005-8]. C1 Gen Atom Co, San Diego, CA 92186 USA. Tennessee Technol Univ, Cookeville, TN 38505 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Parks, PB (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 18 TC 68 Z9 72 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1968 EP 1975 DI 10.1063/1.874052 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000045 ER PT J AU Ferron, JR Chu, MS Jackson, GL Lao, LL Miller, RL Osborne, TH Snyder, PB Strait, EJ Taylor, TS Turnbull, AD Garofalo, AM Makowski, MA Rice, BW Chance, MS Baylor, LR Murakami, M Wade, MR AF Ferron, JR Chu, MS Jackson, GL Lao, LL Miller, RL Osborne, TH Snyder, PB Strait, EJ Taylor, TS Turnbull, AD Garofalo, AM Makowski, MA Rice, BW Chance, MS Baylor, LR Murakami, M Wade, MR TI Modification of high mode pedestal instabilities in the DIII-D tokamak SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID EDGE-LOCALIZED MODES; CURRENT PROFILES; BALLOONING MODE; STABILITY; PLASMAS AB The amplitude and frequency of modes driven in the edge region of tokamak high mode (H-mode) discharges [type I edge-localized modes (ELMs)] are shown to depend on the discharge shape. The measured pressure gradient threshold for instability and its scaling with discharge shape are compared with predictions from ideal magnetohydrodynamic theory for low toroidal mode number (n) instabilities driven by pressure gradient and current density and good agreement is found. Reductions in mode amplitude are observed in discharge shapes with either high squareness or low triangularity where the stability threshold in the edge pressure gradient is predicted to be reduced and the most unstable mode is expected to have higher values of n. The importance of access to the ballooning mode second stability regime is demonstrated through the changes in the ELM character that occur when second regime access is not available. An edge stability model is presented that predicts that there is a threshold value of n for second regime access and that the most unstable mode has n near this threshold. (C) 2000 American Institute of Physics. [S1070-664X(00)97205-7]. C1 Gen Atom Co, San Diego, CA 92186 USA. Columbia Univ, New York, NY 10027 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Xerogen, Alameda, CA 94501 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ferron, JR (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 30 TC 65 Z9 65 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1976 EP 1983 DI 10.1063/1.874053 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000046 ER PT J AU Ditmire, T Zweiback, J Yanovsky, VP Cowan, TE Hays, G Wharton, KB AF Ditmire, T Zweiback, J Yanovsky, VP Cowan, TE Hays, G Wharton, KB TI Nuclear fusion in gases of deuterium clusters heated with a femtosecond laser SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID X-RAY-EMISSION; ATOMIC CLUSTERS; EXPLOSION; PULSES AB Recent experiments on the interaction of intense, ultrafast pulses with large van der Waals bonded clusters have shown that these clusters can explode with substantial kinetic energy. Producing explosions in deuterium clusters with a 35 fs laser pulse, deuterium ions were accelerated to sufficient kinetic energy to drive deuterium-deuterium (DD) nuclear fusion. By diagnosing the fusion yield through measurements of 2.45 MeV fusion neutrons, over 10(4) neutrons per laser shot were measured when 100 mJ of laser energy is used. (C) 2000 American Institute of Physics. [S1070-664X(00)90605-0]. C1 Univ Calif Lawrence Livermore Natl Lab, Laser Program, Livermore, CA 94550 USA. RP Ditmire, T (reprint author), Univ Calif Lawrence Livermore Natl Lab, Laser Program, Livermore, CA 94550 USA. RI Yanovsky, Victor/B-5899-2008; Cowan, Thomas/A-8713-2011 OI Cowan, Thomas/0000-0002-5845-000X NR 24 TC 53 Z9 55 U1 1 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1993 EP 1998 DI 10.1063/1.874020 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000048 ER PT J AU Kalantar, DH Remington, BA Colvin, JD Mikaelian, KO Weber, SV Wiley, LG Wark, JS Loveridge, A Allen, AM Hauer, AA Meyers, MA AF Kalantar, DH Remington, BA Colvin, JD Mikaelian, KO Weber, SV Wiley, LG Wark, JS Loveridge, A Allen, AM Hauer, AA Meyers, MA TI Solid-state experiments at high pressure and strain rate SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID X-RAY-DIFFRACTION; LASER-SHOCKED CRYSTALS; CONSTITUTIVE MODEL; DEFORMATION; ALUMINUM; DYNAMICS AB Experiments have been developed using high powered laser facilities to study the response of materials in the solid state under extreme pressures and strain rates. Details of the target and drive development required for solid-state experiments and results from two separate experiments are presented. In the first, thin foils were compressed to a peak pressure of 180 GPa and accelerated. A pre-imposed modulation at the embedded Rayleigh-Taylor unstable interface was observed to grow. The growth rates were fluid-like at early time, but suppressed at later time. This result is suggestive of the theory of localized heating in shear bands, followed by conduction of the heat into the bulk material, allowing for recovery of the bulk material strength. In the second experiment, the response of Si was studied by dynamic x-ray diffraction. The crystal was observed to respond with uni-axial compression at a peak pressure 11.5-13.5 GPa. (C) 2000 American Institute of Physics. [S1070-664X(00)94505-1]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. RP Kalantar, DH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Meyers, Marc/A-2970-2016 OI Meyers, Marc/0000-0003-1698-5396 NR 31 TC 45 Z9 46 U1 0 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 1999 EP 2006 DI 10.1063/1.874021 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000049 ER PT J AU Goldman, SR Barnes, CW Caldwell, SE Wilson, DC Batha, SH Grove, JW Gittings, ML Hsing, WW Kares, RJ Klare, KA Kyrala, GA Margevicius, RW Weaver, RP Wilke, MD Dunne, AM Edwards, MJ Graham, P Thomas, BR AF Goldman, SR Barnes, CW Caldwell, SE Wilson, DC Batha, SH Grove, JW Gittings, ML Hsing, WW Kares, RJ Klare, KA Kyrala, GA Margevicius, RW Weaver, RP Wilke, MD Dunne, AM Edwards, MJ Graham, P Thomas, BR TI Production of enhanced pressure regions due to inhomogeneities in inertial confinement fusion targets SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID DRIVEN CYLINDRICAL IMPLOSIONS; INSTABILITY AB It is shown that regions of enhanced pressure have been produced in targets with indirect radiation drive in planar and cylindrically convergent geometry through the interaction between the flows caused by target inhomogeneities and the main target drive. Design calculations for National Ignition Facility (NIF) [J. A. Paisner et al., Laser Focus World 30, 75 (1994)] targets with beryllium ablators formed by bonded hemi-shells [D. C. Wilson et al., Bull. Am. Phys. Soc. 43, 1667 (1998)] indicate that related behavior produces a seed perturbation in the ablator which can in some cases lead to the suppression of ignition. From simulation and analysis of the NIF problem in the planar geometry analog, a scaling for the perturbation, which should be useful for validation of the behavior with lower energy drive and smaller-scale geometries, is derived. (C) 2000 American Institute of Physics. [S1070-664X(00)94005-9]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Atom Weap Estab, Reading RG7 4PR, Berks, England. RP Goldman, SR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Dunne, Mike/B-4318-2014 OI Dunne, Mike/0000-0001-8740-3870 NR 21 TC 7 Z9 7 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2007 EP 2013 DI 10.1063/1.874022 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000050 ER PT J AU Tanaka, KA Kodama, R Fujita, H Heya, M Izumi, N Kato, Y Kitagawa, Y Mima, K Miyanaga, N Norimatsu, T Pukhov, A Sunahara, A Takahashi, K Allen, M Habara, H Iwatani, T Matusita, T Miyakosi, T Mori, M Setoguchi, H Sonomoto, T Tanpo, M Tohyama, S Azuma, H Kawasaki, T Komeno, T Maekawa, O Matsuo, S Shozaki, T Suzuki, K Yoshida, H Yamanaka, T Sentoku, Y Weber, F Barbee, TW DaSilva, L AF Tanaka, KA Kodama, R Fujita, H Heya, M Izumi, N Kato, Y Kitagawa, Y Mima, K Miyanaga, N Norimatsu, T Pukhov, A Sunahara, A Takahashi, K Allen, M Habara, H Iwatani, T Matusita, T Miyakosi, T Mori, M Setoguchi, H Sonomoto, T Tanpo, M Tohyama, S Azuma, H Kawasaki, T Komeno, T Maekawa, O Matsuo, S Shozaki, T Suzuki, K Yoshida, H Yamanaka, T Sentoku, Y Weber, F Barbee, TW DaSilva, L TI Studies of ultra-intense laser plasma interactions for fast ignition SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID OVERDENSE PLASMAS; PULSE; EMISSION; TARGETS AB Laser plasma interactions in a relativistic parameter regime have been intensively investigated for studying the possibility of fast ignition in inertial confinement fusion (ICF). Using ultra-intense laser systems and particle-in-cell (PIC) simulation codes, relativistic laser light self-focusing, super hot electrons, ions, and neutron production, are studied. The experiments are performed with ultra-intense laser with 50 J energy, 0.5-1 ps pulse at 1053 nm laser wavelength at a laser intensity of 10(19) W/cm(2). Most of the laser shots are studied under preformed plasma conditions with a 100 mu m plasma scale length condition. In the study of laser pulse behavior in the preformed plasmas, a special mode has been observed which penetrated the preformed plasma all the way very close to the original planar target surface. On these shots, super hot electrons have been observed with its energy peak exceeding 1 MeV. The energy transport of the hot electrons has been studied with making use of K alpha emissions from a seeded metal layer in planar targets. The details of ion acceleration followed by beam fusion reaction have been studied with neutron spectrometers. Laser ponderomotive force self-focusing and hot electron generation have been applied to a compressed core to see the effect of heating by injecting 12 beams of 100 ps, 1 TW pulses. (C) 2000 American Institute of Physics. [S1070-664X(00)95605-2]. C1 Osaka Univ, Inst Laser Engn, Suita, Osaka 5650871, Japan. Inst Laser Technol, Osaka 5500004, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Osaka Univ, Dept Electro Informat Syst & Energy Engn, Suita, Osaka 5650871, Japan. Max Planck Inst Quantum Opt, D-85748 Garching, Germany. RP Tanaka, KA (reprint author), Osaka Univ, Inst Laser Engn, 2-6 Yamada Oka, Suita, Osaka 5650871, Japan. RI Toyama, Yusuke/H-8023-2012; Miyanaga, Noriaki/F-1340-2015; Norimatsu, Takayoshi/I-5710-2015; pukhov, alexander/C-8082-2016; Mima, Kunioki/H-9014-2016; Kodama, Ryosuke/G-2627-2016; IZUMI, Nobuhiko/J-8487-2016; Sentoku, Yasuhiko/P-5419-2014; OI Toyama, Yusuke/0000-0003-3230-1062; Miyanaga, Noriaki/0000-0002-9902-5392; IZUMI, Nobuhiko/0000-0003-1114-597X; SUNAHARA, ATSUSHI/0000-0001-7543-5226 NR 31 TC 100 Z9 104 U1 3 U2 16 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2014 EP 2022 DI 10.1063/1.874023 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000051 ER PT J AU Still, CH Berger, RL Langdon, AB Hinkel, DE Suter, LJ Williams, EA AF Still, CH Berger, RL Langdon, AB Hinkel, DE Suter, LJ Williams, EA TI Filamentation and forward Brillouin scatter of entire smoothed and aberrated laser beams SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID INERTIAL CONFINEMENT FUSION; RANDOM-PHASE PLATE; TRANSVERSE-PLASMA FLOW; STIMULATED BRILLOUIN; HOT-SPOTS; INSTABILITY SUPPRESSION; LIGHT; IGNITION; SIMULATION; DEFLECTION AB Laser-plasma interactions are sensitive to both the fine-scale speckle and the larger scale envelope intensity of the beam. For some time, simulations have been done on volumes taken from part of the laser beam cross-section, and the results from multiple simulations extrapolated to predict the behavior of the entire beam. However, such extrapolation could very well miss effects of the larger scale structure on the fine-scale. The only definitive method is to simulate the entire beam. These very large calculations have not been feasible until recently, but they are now possible on massively parallel computers. Whole beam simulations show the dramatic difference in the propagation and break up of smoothed and aberrated beams. [S1070-664X(00)96505-4]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Still, CH (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave,L-031, Livermore, CA 94550 USA. NR 54 TC 45 Z9 46 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2023 EP 2032 DI 10.1063/1.874055 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000052 ER PT J AU Glendinning, SG Colvin, J Haan, S Kalantar, DH Landen, OL Marinak, MM Remington, BA Wallace, R Cherfils, C Dague, N Divol, L Galmiche, D Richard, AL AF Glendinning, SG Colvin, J Haan, S Kalantar, DH Landen, OL Marinak, MM Remington, BA Wallace, R Cherfils, C Dague, N Divol, L Galmiche, D Richard, AL TI Ablation front Rayleigh-Taylor growth experiments in spherically convergent geometry SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID INSTABILITY; DENSITY; NOVA AB Experiments were performed on the Nova laser [E. M. Campbell et al., Rev. Sci. Instrum. 57, 2101 (1986)], using indirectly driven capsules mounted in cylindrical gold hohlraums, to measure the Rayleigh-Taylor growth at the ablation front by time-resolved radiography. Modulations were preformed on the surface of Ge-doped plastic capsules. With initial modulation amplitude of 2-2.5 mu m, growth factors of about six in optical depth were seen, in agreement with simulations using the radiation hydrocode FCI2 [G. Schurtz, La fusion thermonucleaire inertielle par laser, edited by R. Dautray et al. (Eyrolles, Paris, 1994), Vol. 2]. With initial modulation amplitude of 0.5 mu m and a longer drive, growth factors of about 100-150 in optical depth were seen. Comparable planar experiments showed growth factors of about 40 in optical depth. Analytical models predict the observed growth factors. (C) 2000 American Institute of Physics. [S1070-664X(00)94605-6]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. CEA, Direct Applicat Mil Ile France, F-91680 Bruyeres Le Chatel, France. RP Glendinning, SG (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 25 TC 46 Z9 47 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2033 EP 2039 DI 10.1063/1.874024 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000053 ER PT J AU Benage, JF AF Benage, JF TI Review of electrical resistivity measurements of dense aluminum and comparison to theory SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID STRONGLY COUPLED PLASMA; CONDUCTIVITY; DEGENERATE; METAL AB Four recent experiments that measured the electrical resistivity of aluminum at conditions where the aluminum is in a dense, strongly coupled, plasma state have been analyzed. The properties of dense, strongly coupled plasmas cannot be treated using standard plasma theory, which treats the correlations among particles as a small effect. Many theories have been developed which predict the properties of such plasmas, but there is little experimental data with which to compare. These recent experiments provide data for a comprehensive comparison of electrical resistivity with dense plasma theories. The experiments were carried out under a wide range of conditions, from temperatures < 1 eV up to 25 eV and densities from nearly solid to < 1% solid. The data from these experiments are compared with various theoretical models, the best of which give predictions consistent with the data for most of the experimental conditions, but not all. A discussion of yet unresolved issues is also presented. (C) 2000 American Institute of Physics. [S1070-664X(00)91605-7]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Benage, JF (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 19 TC 20 Z9 20 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2040 EP 2045 DI 10.1063/1.874025 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000054 ER PT J AU Hall, CA AF Hall, CA TI Isentropic compression experiments on the Sandia Z accelerator SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys AB A long-standing goal of the equation of state (EOS) community has been the development of a loading capability for direct measurement of material properties along an isentrope. Previous efforts on smooth bore launchers have been somewhat successful, but quite difficult to accurately reproduce, had pressure limitations, or tended to be a series of small shocks as opposed to a smoothly increasing pressure load. A technique has recently been developed on the Sandia National Laboratories Z accelerator which makes use of the high current densities and magnetic fields available to produce nearly isentropic compression of samples that are approximately 1 mm in thickness over approximately 120 ns. Velocity interferometry is used to measure the rear surface motion of these samples. The resulting time resolved velocity profiles from multiple sample thicknesses provide information about mechanical response under isentropic loading conditions and phase transition kinetics. Feasibility experiments have been performed to pressures of approximately 130 kbar in copper and 300 kbar in iron with effects of the alpha-epsilon phase change kinetics in iron clearly observed. Work is in progress to achieve 1%-2% accuracy in P-upsilon space along an isentrope, provide uniaxial strain, and to eliminate magnetic field and current diffusion within the sample of interest. (C) 2000 American Institute of Physics. [S1070-664X(00)93705-4]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hall, CA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 52 Z9 61 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2069 EP 2075 DI 10.1063/1.874029 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000058 ER PT J AU Hatchett, SP Brown, CG Cowan, TE Henry, EA Johnson, JS Key, MH Koch, JA Langdon, AB Lasinski, BF Lee, RW Mackinnon, AJ Pennington, DM Perry, MD Phillips, TW Roth, M Sangster, TC Singh, MS Snavely, RA Stoyer, MA Wilks, SC Yasuike, K AF Hatchett, SP Brown, CG Cowan, TE Henry, EA Johnson, JS Key, MH Koch, JA Langdon, AB Lasinski, BF Lee, RW Mackinnon, AJ Pennington, DM Perry, MD Phillips, TW Roth, M Sangster, TC Singh, MS Snavely, RA Stoyer, MA Wilks, SC Yasuike, K TI Electron, photon, and ion beams from the relativistic interaction of Petawatt laser pulses with solid targets SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID PLASMA INTERACTIONS AB In recent Petawatt laser experiments at Lawrence Livermore National Laboratory, several hundred joules of 1 mu m laser light in 0.5-5.0-ps pulses with intensities up to 3 x 10(20) W cm(-2) were incident on solid targets and produced a strongly relativistic interaction. The energy content, spectra, and angular patterns of the photon, electron, and ion radiations have all been diagnosed in a number of ways, including several novel (to laser physics) nuclear activation techniques. About 40%-50% of the laser energy is converted to broadly beamed hot electrons. Their beam centroid direction varies from shot to shot, but the resulting bremsstrahlung beam has a consistent width. Extraordinarily luminous ion beams (primarily protons) almost precisely normal to the rear of various targets are seen-up to 3 x 10(13) protons with kT(ion) similar to several MeV representing similar to 6% of the laser energy. Ion energies up to at least 55 MeV are observed. The ions appear to originate from the rear target surfaces. The edge of the ion beam is very sharp, and collimation increases with ion energy. At the highest energies, a narrow feature appears in the ion spectra, and the apparent size of the emitting spot is smaller than the full back surface area. Any ion emission from the front of the targets is much less than from the rear and is not sharply beamed. The hot electrons generate a Debye sheath with electrostatic fields of order MV per micron, which apparently accelerate the ions. (C) 2000 American Institute of Physics. [S1070-664X(00)93905-3]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. GSI Lab, Darmstadt, Germany. RP Hatchett, SP (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI MacKinnon, Andrew/P-7239-2014; Cowan, Thomas/A-8713-2011 OI MacKinnon, Andrew/0000-0002-4380-2906; Cowan, Thomas/0000-0002-5845-000X NR 16 TC 760 Z9 774 U1 4 U2 46 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2076 EP 2082 DI 10.1063/1.874030 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000059 ER PT J AU Callahan-Miller, DA Tabak, M AF Callahan-Miller, DA Tabak, M TI Progress in target physics and design for heavy ion fusion SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID NATIONAL-IGNITION-FACILITY; PLASMA; ENERGY; POWER; GAIN AB Two-dimensional, integrated calculations of a close-coupled version of the distributed radiator, heavy ion target predict gain 130 from 3.3 MJ of beam energy. To achieve these results, the case-to-capsule ratio was decreased by about 25% from the previous heavy ion targets [M. Tabak and D. Callahan-Miller, Phys. Plasmas 5, 1895 (1998)]. These targets are robust to changes in the ion stopping model because changes in the ion stopping model can be accommodated by changes to the target. The capsule is also insensitive to changes in the deuterium-tritium (DT) gas fill in the center of the capsule over the range that is of interest for target fabrication and target injection. Single-mode Rayleigh-Taylor growth rates for this capsule are smaller than those for at least one National Ignition Facility (NIF) [J. A. Paisner et al., Laser Focus World 30, 75 (1994)] design. As a result, stability issues for the heavy ion capsule can be settled on NIF. The close-coupled target also opens up the possibility of a high gain engineering test facility from a 1.5-2 MJ driver; calculations predict that gain 90 is achievable from 1.75 MJ of beam energy. Finally, the choice of hohlraum wall material, which must satisfy constraints from target physics, environment and safety, chamber design, and target fabrication, is discussed. (C) 2000 American Institute of Physics. [S1070-664X(00)90805-X]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Callahan-Miller, DA (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-015,POB 808, Livermore, CA 94550 USA. NR 23 TC 52 Z9 52 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2083 EP 2091 DI 10.1063/1.874031 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000060 ER PT J AU Suter, L Rothenberg, J Munro, D Van Wonterghem, B Haan, S AF Suter, L Rothenberg, J Munro, D Van Wonterghem, B Haan, S TI Exploring the limits of the National Ignition Facility's capsule coupling SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID ROSSELAND MEAN OPACITY; NOVA LASER SYSTEM; HIGH-TEMPERATURES; DRIVE; DESIGN AB The original ignition "point designs" (circa 1992) for the National Ignition Facility (NIF) [J. A. Paisner, E. M. Campbell, and W. J. Hogan, Fusion Technol. 26, 755 (1994)] were made energetically conservative to provide margin for uncertainties in laser absorption, x-ray conversion efficiency and hohlraum-capsule coupling. Since that time, extensive experiments on Nova [J. T. Hunt and D. R. Speck, Opt. Eng. 28, 461 (1989)] and Omega [J. M. Soures et al., Phys. Plasmas 3, 2108 (1996)] and their related analysis indicate that NIF coupling efficiency may be almost "as good as we could hope for." Given close agreement between experiment and theory/modeling, one can credibly explore target enhancements which couple more of NIFs energy to an ignition capsule. These include using optimized mixtures of materials to reduce x-ray wall losses, slightly reduced laser entrance holes, and laser operation strategies which increase the amount of energy one can extract from NIF. It is found that 3-4x increases in absorbed capsule energy appear possible, providing a potentially more robust target and similar to 10x increase in capsule yield. [S1070-664X(00)94805-5]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Suter, L (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 26 TC 46 Z9 49 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2092 EP 2098 DI 10.1063/1.873913 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000061 ER PT J AU Edwards, J Glendinning, SG Suter, LJ Remington, BA Landen, O Turner, RE Shepard, TJ Lasinski, B Budil, K Robey, H Kane, J Louis, H Wallace, R Graham, P Dunne, M Thomas, BR AF Edwards, J Glendinning, SG Suter, LJ Remington, BA Landen, O Turner, RE Shepard, TJ Lasinski, B Budil, K Robey, H Kane, J Louis, H Wallace, R Graham, P Dunne, M Thomas, BR TI Turbulent hydrodynamics experiments using a new plasma piston SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; INERTIAL CONFINEMENT FUSION; RICHTMYER-MESHKOV INSTABILITY; RADIATIVELY DRIVEN SHOCKS; NUMERICAL-SIMULATION; EVOLUTION; SN-1987A; LASER AB A new method for performing compressible hydrodynamic instability experiments using high-power lasers is presented. A plasma piston is created by supersonically heating a low-density carbon based foam with x-rays from a gold hohlraum heated to similar to 200 eV by a similar to 1 ns Nova laser pulse [E. M. Campbell et al., Laser Part. Beams 9, 209 (1991)]. The piston causes an almost shockless acceleration of a thin, higher-density payload consisting of a layer of gold, initially 1/2 mu m thick, supported on 10 mu m of solid plastic, at similar to 45 mu m/ns(2). The payload is also heated by hohlraum x-rays to in excess of 150 eV so that the Au layer expands to similar to 20 mu m prior to the onset of instability growth. The Atwood number between foam and Au is similar to 0.7. Rayleigh-Taylor instability, seeded by the random fibrous structure of the foam, causes a turbulent mixing region with a Reynolds number > 10(5) to develop between piston and Au. The macroscopic width of the mixing region was inferred from the change in Au layer width, which was recorded via time resolved x-radiography. The mix width thus inferred is demonstrated to depend on the magnitude of the initial foam seed. For a small initial seed, the bubble front in the turbulent mixing region is estimated indirectly to grow as similar to 0.036 +/- 0.19 [integral root(Ag)dt](2) which would imply for a constant acceleration 0.036 +/- 0.019 Agt(2). More direct measurement techniques must be developed in larger scale experiments to remove potential complicating factors and reduce the error bar to a level that would permit the measurements to discriminate between various theories and models of turbulent mixing. (C) 2000 American Institute of Physics. [S1070-664X(00)95305-9]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Atom Weap Estab PLC, Reading RG7 4PR, Berks, England. RP Edwards, J (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI Dunne, Mike/B-4318-2014 OI Dunne, Mike/0000-0001-8740-3870 NR 42 TC 8 Z9 8 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2099 EP 2107 DI 10.1063/1.874177 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000062 ER PT J AU Moody, JD MacGowan, BJ Glenzer, SH Kirkwood, RK Kruer, WL Montgomery, DS Schmitt, AJ Williams, EA Stone, GF AF Moody, JD MacGowan, BJ Glenzer, SH Kirkwood, RK Kruer, WL Montgomery, DS Schmitt, AJ Williams, EA Stone, GF TI Experimental investigation of short scalelength density fluctuations in laser-produced plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID INERTIAL CONFINEMENT FUSION; STIMULATED BRILLOUIN-SCATTERING; UNDERDENSE PLASMAS; FILAMENTATION; BEAM; TARGETS; IGNITION; NOVA; PROPAGATION; SUPPRESSION AB The technique of near forward laser scattering is used to infer characteristics of intrinsic and controlled density fluctuations in laser-produced plasmas. Intrinsic fluctuations are studied in long-scalelength plasmas where it is found that the fluctuations exhibit scale sizes related to the intensity variation scales in the plasma forming and interaction beams. Stimulated Brillouin forward scattering and filamentation appear to be the primary mechanism through which these fluctuations originate. The beam spray resulting from these fluctuations is important to understand, since it can affect symmetry in an inertial confinement fusion (ICF) experiment. Controlled fluctuations are studied in foam and exploding foil targets. Forward scattered light from foam targets shows evidence that the initial target inhomogeneities remain after the target is laser heated. Forward scattered light from an exploding foil plasma shows that a regular intensity pattern can be used to produce a spatially correlated density fluctuation pattern. These results provide data which are being used to benchmark numerical models of beam spray. [S1070-664X(00)96705-3]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Moody, JD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 43 TC 9 Z9 9 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2114 EP 2125 DI 10.1063/1.874056 PN 2 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000064 ER PT J AU Back, CA Bauer, JD Hammer, JH Lasinski, BF Turner, RE Rambo, PW Landen, OL Suter, LJ Rosen, MD Hsing, WW AF Back, CA Bauer, JD Hammer, JH Lasinski, BF Turner, RE Rambo, PW Landen, OL Suter, LJ Rosen, MD Hsing, WW TI Diffusive, supersonic x-ray transport in radiatively heated foam cylinders SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID INERTIAL CONFINEMENT FUSION; LASER-DRIVEN SHOCKS; THERMAL-RADIATION; CONVERSION; ENERGY; LIGHT; PLASMAS; TARGETS; MODEL; WAVES AB Diffusive supersonic radiation transport, where the ratio of the diffusive radiation front velocity to the material sound speed > 2 has been studied in experiments on low density (40 mg/cc to 50 mg/cc) foams. Laser-heated Au hohlraums provided a radiation drive that heated SiO2 and Ta2O5 aerogel foams of varying lengths. Face-on emission measurements at 550 eV provided clean signatures of the radiation breakout. The high quality data provides new detailed information on the importance of both the fill and wall material opacities and heat capacities in determining the radiation front speed and curvature. The Marshak radiation wave transport is studied in a geometry that allows direct comparisons with analytic models and two-dimensional code simulations. Experiments show important effects that will affect even nondiffusive and transonic radiation transport experiments studied by others in the field. This work is of basic science interest with applications to inertial confinement fusion and astrophysics. [S1070-664X(00)97405-6]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Back, CA (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-21,POB 808, Livermore, CA 94551 USA. NR 40 TC 34 Z9 43 U1 1 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2126 EP 2134 DI 10.1063/1.874057 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000065 ER PT J AU Drake, RP Carroll, JJ Smith, TB Keiter, P Glendinning, SG Hurricane, O Estabrook, K Ryutov, DD Remington, BA Wallace, RJ Michael, E McCray, R AF Drake, RP Carroll, JJ Smith, TB Keiter, P Glendinning, SG Hurricane, O Estabrook, K Ryutov, DD Remington, BA Wallace, RJ Michael, E McCray, R TI Laser experiments to simulate supernova remnants SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID SN 1987A; EJECTA; DRIVEN; RING; INSTABILITIES; SN-1987A; BULLETS; NEBULA; SHELL; WAVES AB An experiment using a large laser facility to simulate young supernova remnants (SNRs) is discussed. By analogy to the SNR, the laboratory system includes dense matter that explodes, expansion and cooling to produce energetic, flowing plasma, and the production of shock waves in lower-density surrounding matter. The scaling to SNRs in general and to SN1987A in particular is reviewed. The methods and results of x-ray radiography, by which the system in diagnosed, are discussed. The data show that the hohlraum used to provide the energy for explosion does so in two ways-first, through its radiation pulse, and second, through an additional impulse that is attributed to stagnation pressure. Attempts to model these dynamics are discussed. (C) 2000 American Institute of Physics. [S1070-664X(00)93105-7]. C1 Univ Michigan, Ann Arbor, MI 48109 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Colorado, Joint Inst Lab Astrophys, Boulder, CO 80309 USA. RP Drake, RP (reprint author), Univ Michigan, Ann Arbor, MI 48109 USA. RI Drake, R Paul/I-9218-2012; Keiter, Paul/J-3037-2013 OI Drake, R Paul/0000-0002-5450-9844; NR 34 TC 11 Z9 12 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2142 EP 2148 DI 10.1063/1.874034 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000067 ER PT J AU Birn, J Thomsen, MF Borovsky, JE Reeves, GD Hesse, M AF Birn, J Thomsen, MF Borovsky, JE Reeves, GD Hesse, M TI Particle acceleration in the dynamic magnetotail SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID GEOSYNCHRONOUS OBSERVATIONS; INJECTIONS; SIMULATIONS; ORBIT AB The acceleration of charged particles to suprathermal energies is investigated in the context of magnetospheric substorms. Ion and electron test particle orbits are studied in dynamically evolving fields obtained from a three-dimensional resistive magnetohydrodynamic (MHD) simulation of reconnection in the near magnetotail. The simulation leads to plasmoid formation and ejection into the distant tail and an earthward collapse of the field in the inner tail. Energization of particles takes place predominantly in the inner tail region earthward of the neutral line, rather than in the vicinity of the neutral line. The test particle studies reproduce major observed characteristics of energetic particle flux increases ("injections") in the inner magnetotail; a fast rise, a limited energy range of the flux increases, and spatially varying delays between the onsets of ion and electron injections. Acceleration mechanisms include a "quasipotential" acceleration, resulting from nonadiabatic particle motion in the direction of the cross-tail electric field, as well as betatron and Fermi-type acceleration. The major source region for accelerated ions (electrons) in the hundreds of keV range is the central plasma sheet at the dawn (dusk) flank, outside the reconnection site. Since this source plasma is already hot and dense, a moderate energization by a factor of approximately 2 is sufficient to explain the observed increases in the energetic particle fluxes. Differences between ions and electrons at energies of a few tens of keV are found to be associated with differences in the bounce periods, which enables ions to circumvent the acceleration region, so that only electron fluxes in that energy range become enhanced. (C) 2000 American Institute of Physics. [S1070-664X(00)93805-9]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20770 USA. RP Birn, J (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. RI Hesse, Michael/D-2031-2012; Reeves, Geoffrey/E-8101-2011 OI Reeves, Geoffrey/0000-0002-7985-8098 NR 20 TC 17 Z9 17 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2149 EP 2156 DI 10.1063/1.874035 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000068 ER PT J AU Scime, EE Keiter, PA Balkey, MM Boivin, RF Kline, JL Blackburn, M Gary, SP AF Scime, EE Keiter, PA Balkey, MM Boivin, RF Kline, JL Blackburn, M Gary, SP TI Ion temperature anisotropy limitation in high beta plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID PROTON CYCLOTRON INSTABILITY; EARTHS MAGNETOSHEATH; DEPLETION LAYER; MIRROR PLASMAS; FLUCTUATIONS; TOMOGRAPHY AB Measurements of parallel and perpendicular ion temperatures in the Large Experiment on Instabilities and Anisotropies (LEIA) space simulation chamber display an inverse correlation between the upper bound on the ion temperature anisotropy and the parallel ion beta (beta = 8 pi nkT/B-2). Fluctuation measurements indicate the presence of low frequency, transverse, electromagnetic waves with wave numbers and frequencies that are consistent with predictions for Alfven Ion Cyclotron instabilities. These observations are also consistent with in situ spacecraft measurements in the Earth's magnetosheath and with a theoretical/computational model that predicts that such an upper bound on the ion temperature anisotropy is imposed by scattering from enhanced fluctuations due to growth of the Alfven ion cyclotron instability. (C) 2000 American Institute of Physics. [S1070-664X(00)91405-8]. C1 W Virginia Univ, Morgantown, WV 26506 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Scime, EE (reprint author), W Virginia Univ, Morgantown, WV 26506 USA. RI Keiter, Paul/J-3037-2013 NR 39 TC 34 Z9 34 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2157 EP 2165 DI 10.1063/1.874036 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000069 ER PT J AU Kwan, TJT Snell, CM Christenson, PJ AF Kwan, TJT Snell, CM Christenson, PJ TI Electron beam-target interaction and spot size stabilization in flash x-ray radiography SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys AB A high current relativistic electron beam incident on a high-Z target to produce bremsstrahlung photons for radiographic applications can be subjected to charge neutralization by target plasma ion production due to energy deposition by the electron beam. This partial charge neutralization can lead to premature focusing of the electron beam at a distance away from the target and subsequent radial divergence. Furthermore, as the ion column continues to expand, the focal point moves upstream along the path of the electron beam, causing the beam spot on the target to grow in time. The increase in radiation spot size is detrimental to the spatial resolution of radiographic images. The ion effects were confirmed via particle-in-cell simulations and analysis, and methods were investigated to suppress the growth of the electron beam spot size in single- and multiple-pulse radiographic applications. The concept of a self-biased target was proposed and validated by computer simulation showing that the electron beam can be used in a configuration to establish an electric potential between the target and the collimator. This potential can effectively trap the ions, limit the ion column length, and thereby maintain the electron beam spot size. Another approach is the placement of a thin metallic foil at 1-2 cm in front of the target, which serves as a barrier to the ions but is essentially transparent to the incoming electron beam. Our study also showed that optimized confinement of plasma ions with the electromagnetic or the mechanical method can provide an additional ion-focusing effect which leads to a desirable further reduction of the beam spot size. (C) 2000 American Institute of Physics. [S1070-664X(00)93405-0]. C1 Univ Calif Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. RP Kwan, TJT (reprint author), Univ Calif Los Alamos Natl Lab, Div Appl Phys, X-PA,MS B259,POB 1663, Los Alamos, NM 87545 USA. NR 18 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2215 EP 2223 DI 10.1063/1.874043 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000077 ER PT J AU Hogan, MJ Assmann, R Decker, FJ Iverson, R Raimondi, P Rokni, S Siemann, RH Walz, D Whittum, D Blue, B Clayton, CE Dodd, E Hemker, R Joshi, C Marsh, KA Mori, WB Wang, S Katsouleas, T Lee, S Muggli, P Catravas, P Chattopadhyay, S Esarey, E Leemans, WP AF Hogan, MJ Assmann, R Decker, FJ Iverson, R Raimondi, P Rokni, S Siemann, RH Walz, D Whittum, D Blue, B Clayton, CE Dodd, E Hemker, R Joshi, C Marsh, KA Mori, WB Wang, S Katsouleas, T Lee, S Muggli, P Catravas, P Chattopadhyay, S Esarey, E Leemans, WP TI E-157: A 1.4-m-long plasma wake field acceleration experiment using a 30 GeV electron beam from the Stanford Linear Accelerator Center Linac SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 41st Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 15-19, 1999 CL SEATTLE, WASHINGTON SP Amer Phys Soc, Div Plasma Phys ID WAKEFIELD ACCELERATION; LASER WAKEFIELD; WAVE; CHANNEL AB In the E-157 experiment now being conducted at the Stanford Linear Accelerator Center, a 30 GeV electron beam of 2 x 10(10) electrons in a 0.65-mm-long bunch is propagated through a 1.4-m-long lithium plasma of density up to 2 x 10(14) e(-)/cm(3). The initial beam density is greater than the plasma density, and the head of the bunch expels the plasma electrons leaving behind a uniform ion channel with transverse focusing fields of up to several thousand tesla per meter. The initial transverse beam size with sigma = 50-100 mu m is larger than the matched size of 5 mu m resulting in up to three beam envelope oscillations within the plasma. Time integrated optical transition radiation is used to study the transverse beam profile immediately before and after the plasma and to characterize the transverse beam dynamics as a function of plasma density. The head of the bunch deposits energy into plasma wakes, resulting in longitudinal accelerating fields which are witnessed by the tail of the same bunch. A time-resolved Cherenkov imaging system is located in an energy dispersive plane downstream of the plasma. It images the beam onto a streak camera allowing time-resolved measurements of the beam energy spectrum as a function of plasma density. Preliminary experimental data from the first three runs are compared to theory and computer simulations. (C) 2000 American Institute of Physics. [S1070-664X(00)97805-4]. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ So Calif, Los Angeles, CA 90089 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Hogan, MJ (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RI Assmann, Ralph/L-8457-2016 NR 33 TC 46 Z9 47 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 2000 VL 7 IS 5 BP 2241 EP 2248 DI 10.1063/1.874059 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 304XZ UT WOS:000086511000080 ER PT J AU Vrana, TP Dytman, SA Lee, TSH AF Vrana, TP Dytman, SA Lee, TSH TI Baryon resonance extraction from pi N data using a unitary multichannel model SO PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS LA English DT Review ID MESON-NUCLEON SCATTERING; RELATIVIZED QUARK-MODEL; PARTIAL-WAVE ANALYSIS; ETA-PHOTOPRODUCTION; ELECTROPRODUCTION; AMPLITUDES AB A unitary multi-channel approach. first developed by the Carnegie-Mellon Berkeley group, is applied to extract the pole positions, masses, and partial decay widths of nucleon resonances from the partial wave amplitudes for the transitions from pi N to eight possible final baryon-meson states. Results of single energy analyses of the VPI group using the most current database are used in this analysis. A proper treatment of threshold effects and channel coupling within the unitarity constraint is shown to be crucial in extracting resonant parameters, especially for the resonance states, such as S-11(1535), which have decay thresholds very close to the resonance pole position. The extracted masses and partial decay widths of baryon resonances up to about 2 GeV mass are listed and compared with the results from previous analyses. In many cases, the new results agree with previous analyses. However, some significant differences, in particular for the resonances that are weakly excited in pi N reactions, are found. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Dytman, SA (reprint author), Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. EM dytman@pitt.edu NR 43 TC 168 Z9 168 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-1573 J9 PHYS REP JI Phys. Rep.-Rev. Sec. Phys. Lett. PD MAY PY 2000 VL 328 IS 4 BP 181 EP 236 DI 10.1016/S0370-1573(99)00108-8 PG 56 WC Physics, Multidisciplinary SC Physics GA 299VA UT WOS:000086217500001 ER PT J AU Drell, SD AF Drell, SD TI Andrei Sakharov and the nuclear danger SO PHYSICS TODAY LA English DT Article C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Drell, SD (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD MAY PY 2000 VL 53 IS 5 BP 37 EP 41 DI 10.1063/1.883099 PG 5 WC Physics, Multidisciplinary SC Physics GA 309FM UT WOS:000086757700010 ER PT J AU Cordey, JG Alper, B Budny, R Christiansen, JP Coffey, I Erents, K Harbour, P Horton, LD Lawson, K Matthews, GF Saibene, G Sartori, R Strachan, J Thomsen, K AF Cordey, JG Alper, B Budny, R Christiansen, JP Coffey, I Erents, K Harbour, P Horton, LD Lawson, K Matthews, GF Saibene, G Sartori, R Strachan, J Thomsen, K TI Isotope identity experiments in JET SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA AB ELMy H-mode pulses have been obtained with different hydrogenic isotopes (H and D) but having the same profiles of the dimensionless parameters rho*, beta, nu* and q, to test whether the confinement scale invariance principle is valid in a tokamak. The fact that the confinement times, the ELM and sawtooth frequencies in the two pulses all scale as expected suggests that the invariance principle is satisfied through the plasma radial extent, in spite of the differing physical processes taking place in the plasma centre, core and edge regions. An application of this 'isotope windtunnel technique' to predicting the D-T performance of the next step devices is discussed. C1 Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Princeton Univ, PPPL, Princeton, NJ 08544 USA. RP Cordey, JG (reprint author), Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. NR 5 TC 6 Z9 6 U1 0 U2 0 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 MAY PY 2000 VL 42 SU 5A BP A127 EP A132 DI 10.1088/0741-3335/42/5A/312 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000013 ER PT J AU Doyle, EJ Staebler, GM Zeng, L Rhodes, TL Burrell, KH Greenfield, CM Groebner, RJ McKee, GR Peebles, WA Rettig, CL Rice, BW Stallard, BW AF Doyle, EJ Staebler, GM Zeng, L Rhodes, TL Burrell, KH Greenfield, CM Groebner, RJ McKee, GR Peebles, WA Rettig, CL Rice, BW Stallard, BW TI Observation of simultaneous internal transport barriers in all four transport channels and correlation with turbulence behaviour in NCS discharges on DIII-D SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA ID MAGNETIC SHEAR DISCHARGES; FLUID MODEL TURBULENCE; FINITE ASPECT RATIO; D TOKAMAK; HIGH-PERFORMANCE; CONFINEMENT; REFLECTOMETER; PLASMAS AB Very steep internal transport barriers (ITBs) have been observed in all four transport channels on DIII-D. These ITBs are among the most highly localized(width less than or equal to 5 cm), simultaneous core transport barriers observed on any machine to date, and have only been observed in discharges with a negative central magnetic shear (NCS discharges), at power levels above similar to 8 MW. Profile gradients and scale lengths at the location of the core (rho similar to 0.3-0.4) transport barriers are similar to those observed at the plasma edge during H-mode, while profiles inside the transport barriers are flat. The spatial location of the transport barriers coincides in all four transport channels, although the temporal evolution of the profiles is different; very steep gradients in the electron density and temperature profiles form after such gradients are first observed in the ion temperature and angular momentum profiles. Turbulence measurements during the evolution of the core particle transport barrier show no decrease in low-wavenumber (0-6 cm(-1)) turbulence levels in the plasma centre, including within the steep gradient ITB region. Several possible interpretations for this observation are presented. C1 Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, IPFR, Los Angeles, CA 90095 USA. Gen Atom Co, San Diego, CA USA. Univ Wisconsin, Madison, WI USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Doyle, EJ (reprint author), Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. NR 29 TC 35 Z9 35 U1 0 U2 1 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 MAY PY 2000 VL 42 SU 5A BP A237 EP A246 DI 10.1088/0741-3335/42/5A/328 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000029 ER PT J AU Greenwald, M Boivin, R Bonoli, P Fiore, C Goetz, J Granetz, R Hubbard, A Hutchinson, I Irby, J Lin, Y Marmar, E Mazurenko, A Mossessian, D Pedersen, TS Rice, J Snipes, J Schilling, G Taylor, G Terry, J Wolfe, S Wukitch, S AF Greenwald, M Boivin, R Bonoli, P Fiore, C Goetz, J Granetz, R Hubbard, A Hutchinson, I Irby, J Lin, Y Marmar, E Mazurenko, A Mossessian, D Pedersen, TS Rice, J Snipes, J Schilling, G Taylor, G Terry, J Wolfe, S Wukitch, S TI Studies of EDA H-mode in Alcator C-Mod SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA ID CONFINEMENT AB Studies of the enhanced D-alpha H-mode (EDA) have been extended to include ohmic plasmas. No clear difference in the EDA/ELMfree boundary or in other phenomenology are seen between ohmic and ICRF-heated plasmas, suggesting that neither the effect of ion tails nor direct RF/edge plasma interaction plays a role in EDA. Edge safety factor (q(95)) is the principal variable which determines which regime a discharge will be in. When q(95) is greater than 4.0 for standard-shaped plasmas, the discharge is almost always EDA, while when it is less than 3.5, the plasma is almost always ELMfree. New edge diagnostics have allowed measurement of pedestal profiles with resolution of the order of 1 mm. Sudden changes in profile widths are not seen when the plasma makes a transition from EDA to ELMfree; however, the widths do vary with the same parameters that determine the EDA/ELMfree boundary. Strong edge-density fluctuations are observed to accompany EDA and may be responsible for the change in particle transport which is observed. The fluctuations have a quasi-coherent component whose frequency varies inversely with the pedestal width as measured by a visible continuum diagnostic. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Greenwald, M (reprint author), MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. RI Lin, Yijun/B-5711-2009; Hutchinson, Ian/D-1136-2009 OI Hutchinson, Ian/0000-0003-4276-6576 NR 7 TC 53 Z9 53 U1 2 U2 11 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 MAY PY 2000 VL 42 SU 5A BP A263 EP A269 DI 10.1088/0741-3335/42/5A/331 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000032 ER PT J AU Hahm, TS Burrell, KH Lin, Z Nazikian, R Synakowski, EJ AF Hahm, TS Burrell, KH Lin, Z Nazikian, R Synakowski, EJ TI Zonal flow measurements concept I SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA ID TRANSPORT BARRIER FORMATION; FUSION TEST REACTOR; EXB VELOCITY-SHEAR; X-B FLOW; TURBULENT TRANSPORT; EDGE TURBULENCE; MAGNETIC SHEAR; TOKAMAK; PLASMA; FLUCTUATIONS AB We study the characteristics of self-generated zonal flows as observed in nonlinear global gyrokinetic simulations of toroidal ion temperature gradient (ITG) turbulence for typical parameters of DIII-D core plasmas. In addition, we discuss various possibilities for experimental measurements and the development of new diagnostics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Gen Atom Co, San Diego, CA 92186 USA. RP Hahm, TS (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 36 TC 79 Z9 79 U1 0 U2 2 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 MAY PY 2000 VL 42 SU 5A BP A205 EP A210 DI 10.1088/0741-3335/42/5A/323 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000024 ER PT J AU Hidalgo, C Pedrosa, MA Sanchez, E Balbin, R Lopez-Fraguas, A van Milligen, B Silva, C Fernandes, H Varandas, CAF Riccardi, C Carrozza, R Fontanesi, M Carreras, BA Garcia, L AF Hidalgo, C Pedrosa, MA Sanchez, E Balbin, R Lopez-Fraguas, A van Milligen, B Silva, C Fernandes, H Varandas, CAF Riccardi, C Carrozza, R Fontanesi, M Carreras, BA Garcia, L TI Generation of sheared poloidal flows via Reynolds stress and transport barrier physics SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA ID MAGNETIC CONFINEMENT DEVICES; L-H TRANSITION; ANOMALOUS TRANSPORT; EDGE TURBULENCE; VELOCITY-SHEAR; PLASMA; TOKAMAKS; BIFURCATION; DISCHARGES; STABILITY AB A view of the latest experimental results and progress in the understanding of the role of poloidal flows driven by fluctuations via Reynolds stress is given. Reynolds stress shows a radial gradient close to the velocity shear layer location in tokamaks and stellarators, indicating that this mechanism may drive significant poloidal flows in the plasma boundary. Observation of the generation of E x B sheared flows via Reynolds stress at the ion Bernstein resonance layer has been noticed in toroidal magnetized plasmas. The experimental evidence of sheared E x B flows linked to the location of rational surfaces in stellarator plasmas might be interpreted in terms of Reynolds stress sheared driven flows. These results show that E x B sheared flows driven by fluctuations can play an important role in the generation of transport barriers. C1 CIEMAT, EURATOM Assoc, E-28040 Madrid, Spain. Inst Super Tecn, EURATOM Assoc, P-1096 Lisbon, Portugal. Univ Milan, I-20133 Milan, Italy. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Carlos III Madrid, Madrid, Spain. RP Hidalgo, C (reprint author), CIEMAT, EURATOM Assoc, E-28040 Madrid, Spain. RI Sanchez, Edilberto/D-4620-2009; Silva, Carlos/L-6490-2013; Fernandes, Horacio/E-3292-2012; Varandas, Carlos/N-3519-2013; Lopez-Fraguas, Antonio/L-8104-2014; Garcia, Luis/A-5344-2015; van Milligen, Boudewijn/H-5121-2015; Balbin, Rosa/F-8210-2010; Hidalgo, Carlos/H-6109-2015 OI Sanchez, Edilberto/0000-0003-1062-7870; Silva, Carlos/0000-0001-6348-0505; Fernandes, Horacio/0000-0001-6542-7767; Varandas, Carlos/0000-0002-6164-0170; Lopez-Fraguas, Antonio/0000-0002-0277-8137; Garcia, Luis/0000-0002-0492-7466; van Milligen, Boudewijn/0000-0001-5344-6274; Balbin, Rosa/0000-0001-5231-1300; NR 38 TC 48 Z9 48 U1 0 U2 3 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 MAY PY 2000 VL 42 SU 5A BP A153 EP A160 DI 10.1088/0741-3335/42/5A/316 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000017 ER PT J AU Kamada, Y Oikawa, T Lao, L Takizuka, T Hatae, T Isayama, A Manickam, J Okabayashi, M Fukuda, T Tsuchiya, K AF Kamada, Y Oikawa, T Lao, L Takizuka, T Hatae, T Isayama, A Manickam, J Okabayashi, M Fukuda, T Tsuchiya, K TI Disappearance of giant ELMs and appearance of minute grassy ELMs in JT-60U high-triangularity discharges SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA ID H-MODE; EDGE AB In JT-60U H-mode plasmas, giant (type I) ELMs disappear and minute grassy ELMs appear when triangularity delta, edge safety factor q(95) and beta(p) are high enough. Complete suppression of giant ELMs was observed at delta greater than or similar to 0.45, q(95) greater than or similar to 6 and beta(p) greater than or similar to 1.6. At higher delta (0.54), giant ELMs can disappear at a lower q(95) (similar to 4.0) In the grassy ELMy H-mode, edge temperature and pressure can be higher than those in giant ELMy H-mode and a favourable confinement can be sustained without an increase of the impurity concentration. An edge stability analysis suggests that the edge plasma is accessing the second stability regime of the high n ballooning mode in the grassy ELMy discharges. C1 Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 3110193, Japan. Gen Atom Co, San Diego, CA 92186 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kamada, Y (reprint author), Japan Atom Energy Res Inst, Naka Fus Res Estab, 801-1 Mukouyama, Naka, Ibaraki 3110193, Japan. NR 13 TC 76 Z9 76 U1 2 U2 14 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 MAY PY 2000 VL 42 SU 5A BP A247 EP A253 DI 10.1088/0741-3335/42/5A/329 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000030 ER PT J AU Mossessian, D Hubbard, AE Marmar, ES Pedersen, TS Granetz, RS Boivin, RL Greenwald, M Hughes, J Irby, J Johnson, D LaBombard, B Lin, Y Mazurenko, A Nazikian, R Pitcher, CS Taylor, G Wolfe, SM AF Mossessian, D Hubbard, AE Marmar, ES Pedersen, TS Granetz, RS Boivin, RL Greenwald, M Hughes, J Irby, J Johnson, D LaBombard, B Lin, Y Mazurenko, A Nazikian, R Pitcher, CS Taylor, G Wolfe, SM TI Measurements and scalings of the H-mode pedestal on Alcator C-Mod SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA ID IMPURITY TRANSPORT; ENERGY CONFINEMENT; DIII-D AB In this paper we summarize the results of recent measurements of the high confinement mode (H-mode) edge transport barrier in Alcator C-Mod. A number of new, high-resolution edge diagnostics provide measurements of plasma parameters (electron density and temperature, and impurity density) in the pedestal region. Pedestal parameters are measured both at the top edge of the plasma and at the midplane. Very narrow (2-5 mm) electron density and temperature and impurity density pedestals are observed. The impurity pedestal is located inside the density and temperature pedestals in the midplane measurements, bur coincides with the n(e) pedestal at the top edge. Correlation of both width and height of the pedestals at the midplane with global plasma parameters and core confinement characteristics is observed. At the same time there are no clear indications of scaling for the electron density and impurity pedestal widths measured at the top of the plasma. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Mossessian, D (reprint author), MIT, Plasma Sci & Fus Ctr, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Lin, Yijun/B-5711-2009 NR 15 TC 8 Z9 8 U1 0 U2 0 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 MAY PY 2000 VL 42 SU 5A BP A255 EP A262 DI 10.1088/0741-3335/42/5A/330 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000031 ER PT J AU Osborne, TH Ferron, JR Groebner, RJ Lao, LL Leonard, AW Mahdavi, MA Maingi, R Miller, RL Turnbull, AD Wade, M Watkins, J AF Osborne, TH Ferron, JR Groebner, RJ Lao, LL Leonard, AW Mahdavi, MA Maingi, R Miller, RL Turnbull, AD Wade, M Watkins, J TI The effect of plasma shape on H-mode pedestal characteristics on DIII-D SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA ID ELECTRIC-FIELD; TURBULENCE; TOKAMAKS; EDGE; STABILIZATION; STABILITY; SHEAR; ELMS AB The characteristics of the H-mode are studied in discharges with varying triangularity and squareness. The pressure at the top of the H-mode pedestal increases strongly with triangularity, primarily due to an increase in the margin by which the edge pressure gradient exceeds the ideal ballooning mode first stability limit. Two models are considered for how the edge may exceed the ballooning mode limit. in one model, access to the ballooning mode second stable regime allows the edge pressure gradient and associated bootstrap current to continue to increase until an edge localized. low toroidal mode number, ideal kink mode is destabilized. In the second model, the finite width of the H-mode transport barrier and diamagnetic effects raise the pressure gradient limit above the ballooning mode limit. We observe a weak inverse dependence of the width of the H-mode transport barrier, Delta, on triangularity relative to the previously obtained scaling Delta proportional to (beta(P)(PE))(1/2) The energy loss for Type I ELMs increases with triangularity in proportion to the pedestal energy increase. At low density, the energy confinement of high-triangularity discharges is larger than discharges with low triangularity, as a result of an increase in the energy in the H-mode pedestal. At high density, both the change in pedestal pressure and the response of the density profile are found to play a role in setting the energy confinement. The highest energy confinement at high density was obtained in low-triangularity discharges. C1 Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Osborne, TH (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 30 TC 88 Z9 88 U1 0 U2 4 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 MAY PY 2000 VL 42 SU 5A BP A175 EP A184 DI 10.1088/0741-3335/42/5A/319 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000020 ER PT J AU Rognlien, TD Xu, XQ Cohen, RH AF Rognlien, TD Xu, XQ Cohen, RH TI Simulation of edge-plasma profiles and turbulence related to L-H transitions in tokamaks SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA ID ELECTRIC-FIELD; POLOIDAL ROTATION; SEPARATRIX; TRANSPORT; SHEAR AB Results are presented for fluid-equation simulations of transport and turbulence in the edge region of a tokamak using the transport code UEDGE and the turbulence code BOUT. UEDGE calculates two-dimensional plasma and neutral gas profiles using empirical radial transport coefficients, while BOUT simulates three-dimensional plasma turbulence and resulting transport using experimental or UEDGE plasma profiles. Using UEDGE, the radial electric field structure near the magnetic separatrix is studied for variations of core power, anomalous perpendicular ion viscosity, nu(a perpendicular to), and prompt ion loss. A BOUT simulation measures the effective nu(a perpendicular to) from the calculated turbulence-induced radial ion current, giving a value similar to the ion heat diffusivity. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Rognlien, TD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 17 TC 9 Z9 9 U1 1 U2 7 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 MAY PY 2000 VL 42 SU 5A BP A271 EP A276 DI 10.1088/0741-3335/42/5A/332 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000033 ER PT J AU Strachan, JD Budny, R Coffey, I Dumortier, P Grisolia, C Harbour, P von Hellermann, M Hillis, D Hoang, T Hogan, J Horton, LD Ingesson, LC Jackson, G Jaeckel, H Maddison, G Matthews, GF Mayer, M Messiaen, A Monier-Garbet, P Nave, MFN Ongena, J Rapp, J Unterberg, B Wade, M Zastrow, KD AF Strachan, JD Budny, R Coffey, I Dumortier, P Grisolia, C Harbour, P von Hellermann, M Hillis, D Hoang, T Hogan, J Horton, LD Ingesson, LC Jackson, G Jaeckel, H Maddison, G Matthews, GF Mayer, M Messiaen, A Monier-Garbet, P Nave, MFN Ongena, J Rapp, J Unterberg, B Wade, M Zastrow, KD TI JET radiative mantle experiments in ELMy H-mode SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 7th IAEA Technical Committee Meeting on H-Mode and Transport Barrier Physics CY SEP 27-29, 1999 CL OXFORD, ENGLAND SP JET, IAEA ID ASDEX UPGRADE; CONFINEMENT; DISCHARGES; PLASMAS AB Radiative mantle experiments were performed on JET ELMy H-mode plasmas. The septum configuration was used where the X-point is embedded into the top of the septum. Argon radiated 50% of the input power from the bulk plasma while Z(eff) rose from an intrinsic level of 1.5 to about 1.7 due to the injected argon. The total energy content and global energy confinement time decreased 15% when the impurities were introduced. In contrast, the effective thermal diffusivity in the core confinement region (r/a = 0.4-0.8) decreased by 30%. Usually, JET ELMy H-mode plasmas have confinement that Is correlated to the edge pedestal pressure. The radiation lowered the edge pedestal and consequently lowered the global confinement. Thus the global confinement was changed by a competition between the edge pedestal reduction lowering the confinement and the weaker RI effect reducing the core transport coefficients. The ELM frequency increased from 10 Hz type-I ELMs, to 200 Hz type-m ELMs. The energy lost by each ELM reduced to 0.5% of the plasma energy content. C1 Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. RP Strachan, JD (reprint author), Princeton Univ, PPPL, Princeton, NJ 08544 USA. RI Nave, Maria/A-5581-2013 OI Nave, Maria/0000-0003-2078-6584 NR 13 TC 14 Z9 14 U1 0 U2 2 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 MAY PY 2000 VL 42 SU 5A BP A81 EP A88 DI 10.1088/0741-3335/42/5A/306 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 325PZ UT WOS:000087686000007 ER PT J AU Triolo, A Lin, JS Wignall, GD Triolo, R AF Triolo, A Lin, JS Wignall, GD Triolo, R TI Structure of isotactic polypropylene-hydrogenated oligo(cyclopentadiene) (iPP-HOCP) blends Part II. HOCP-rich blends SO POLYMER LA English DT Article DE SAXS; SANS; iPP ID ANGLE X-RAY; LAMELLAR 2-PHASE SYSTEMS; NEUTRON-SCATTERING; PHASE-DIAGRAM; SEMICRYSTALLINE; MORPHOLOGY AB Blends of isotactic polypropylene (iPP) and hydrogenated oligo(cyclopentadiene) (HOCP) were investigated to gain structural information by means of both SAXS and SANS techniques. The composition range (from 30 to 60% w/w HOCP content) and the temperature range (between 25 and 160 degrees C) were chosen in order to cover the miscibility gap in the phase diagram of the material system. In a previous report, blends lying outside the miscibility gap have been investigated and the corresponding SAXS patterns were interpreted in terms of a pseudo-two phase model. For the SAXS patterns, blends lying inside the miscibility gap are rather hard to be interpreted in terms of such a model. On the other hand, SANS patterns display a behaviour that can be directly rationalised in terms of two different coexisting lamellar phases (each corresponding to two domains enriched in either one of the two components). A novel approach is described which allows such a separation of morphological phases. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Heriot Watt Univ, Dept Chem, Edinburgh EH14 4AS, Midlothian, Scotland. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Palermo, Dipartimento Chim Fis, I-90128 Palermo, Italy. RP Triolo, A (reprint author), Heriot Watt Univ, Dept Chem, Edinburgh EH14 4AS, Midlothian, Scotland. RI Triolo, Alessandro/B-7760-2008; Triolo, Alessandro/A-4431-2012; OI Triolo, Alessandro/0000-0003-4074-0743; Wignall, George/0000-0002-3876-3244 NR 23 TC 3 Z9 4 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD MAY PY 2000 VL 41 IS 10 BP 3751 EP 3758 DI 10.1016/S0032-3861(99)00403-6 PG 8 WC Polymer Science SC Polymer Science GA 285KM UT WOS:000085388300028 ER PT J AU Chen, W Moon, IK Wunderlich, B AF Chen, W Moon, IK Wunderlich, B TI Study of crystallization kinetics by temperature-modulated DSC SO POLYMER LA English DT Article DE polymer crystallization; reversible phase transition; irreversible phase transition ID DIFFERENTIAL SCANNING CALORIMETRY; POLY(ETHYLENE-TEREPHTHALATE) AB A method of temperature-modulated differential scanning calorimetry (TMDSC), proposed by Toda et al., is used to study the crystallization kinetics of a polyester-imid, namely poly(4,4'-phthaloimidobenzoyldodecamethyoxycarbonyl). The polymer shows one irreversible melting/crystallization transition and one smaller, partially reversible transition. The experimental results prove that with this method one can obtain an important parameter that characterizes polymer crystallization via the temperature-dependence of the crystal-growth rate. The TMDSC data consist of the total heat flow, the magnitude of the apparent heat capacity, and the change of the phase lag of the heat how in the transition region. No specific assumptions an made about the crystallization kinetics. (C) 2000 Elsevier Science Ltd. 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 Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 28 TC 6 Z9 7 U1 1 U2 6 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD MAY PY 2000 VL 41 IS 11 BP 4119 EP 4125 DI 10.1016/S0032-3861(99)00621-7 PG 7 WC Polymer Science SC Polymer Science GA 288LX UT WOS:000085565200024 ER PT J AU Lee, HS Denn, MM AF Lee, HS Denn, MM TI Blends of linear and branched polyethylenes SO POLYMER ENGINEERING AND SCIENCE LA English DT Article ID MOLECULAR-WEIGHT DISTRIBUTION; HIGH-DENSITY POLYETHYLENE; ANGLE NEUTRON-SCATTERING; PHASE SEGREGATION; POLYMER BLENDS; RHEOLOGICAL PROPERTIES; CRYSTALLINE POLYMERS; VISCOELASTIC LIQUIDS; RELAXATION PROCESSES; SHEAR-FLOW AB We employ rheological measurements of polyethylene blends in the melt and solid state, together with thermal analysis, to infer phase behavior. Partial-miscibility in the melt is characterized by use of the double-reptation model to define the complex modulus of the continuous phase for input into the emulsion model for the blend; this approach introduces a new fitting parameter, the fraction of the minor component contained in the continuous phase. The results on binary systems suggest the use of HDPE as a compatibilizer for LLDPE/LDPE blends, apparently creating a fully miscible ternary system. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Lee, HS (reprint author), LG Chem Ltd, Ctr Tech, Yusgung Gu, Jang Dong 84, Taejon 305343, South Korea. OI Lee, Heon Sang/0000-0002-6806-5666 NR 37 TC 48 Z9 49 U1 3 U2 18 PU SOC PLASTICS ENG INC PI BROOKFIELD PA 14 FAIRFIELD DR, BROOKFIELD, CT 06804-0403 USA SN 0032-3888 J9 POLYM ENG SCI JI Polym. Eng. Sci. PD MAY PY 2000 VL 40 IS 5 BP 1132 EP 1142 DI 10.1002/pen.11241 PG 11 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA 318HB UT WOS:000087276900010 ER PT J AU Hu, MZC Kurian, V Payzant, EA Rawn, CJ Hunt, RD AF Hu, MZC Kurian, V Payzant, EA Rawn, CJ Hunt, RD TI Wet-chemical synthesis of monodispersed barium titanate particles - hydrothermal conversion of TiO2 microspheres to nanocrystalline BaTiO3 SO POWDER TECHNOLOGY LA English DT Article; Proceedings Paper CT AICHE Annual Meeting CY NOV 15-20, 1998 CL MIAMI, FLORIDA SP AICHE DE monodispersed particles; powders; titania; barium titanate; hydrothermal ID DOUBLE-JET PRECIPITATION; HOMOGENEOUS PRECIPITATION; MECHANISMS; KINETICS AB A low-temperature hydrothermal reaction scheme has been developed to produce pure, ultrafine, uniform-sized, nanocrystalline barium titanate (BaTiO3) microspheres from two inorganic precursors: synthesized titania microspheres and barium hydroxide solutions. The size and morphology of titania (TiO2) microspheres were controlled using isopropanol to fine-tune the dielectric constant of the isopropanol-water mixed solvent system. Monodispersed titania microspheres approximately 0.1-1 mu m in diameter were successfully synthesized for the further conversion to barium titanate. Barium titanate and titania microspheres were characterized by scanning electron microscopy (SEM) and room-temperature X-ray diffraction (RTXRD). High-temperature XRD (HTXRD) was also utilized for in situ study of the phase transformations and changes of crystallite size with calcination temperatures. The titania microspheres were predominant in the anatase (plus some brookite) phase at room temperature and were converted to the rutile phase when the calcination temperature was increased from 650 degrees C to 900 degrees C. Monodispersed barium titanate microspheres were successfully synthesized from optimized titania via a hydrothermal reaction (less than or equal to 100 degrees C) in barium hydroxide solutions. The size and morphology of the barium titanate particles remained the same as the precursor titania particles, indicating a "shrinking-core" diffusion-reaction mechanism. Barium carbonate in the form of witherite was also found along with the formation of barium titanate, especially under conditions with higher Ba/Ti ratios, but a formic acid washing procedure effectively removed this impurity phase from the barium titanate samples. The as-prepared barium titanate was in the cubic nanocrystalline form and did not change when the temperature was increased from room temperature to as high as 750 degrees C. The cubic phase was also stable at high temperatures for over 5 h. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Knox Coll, Dept Chem, Galesburg, IL 61401 USA. RP Hu, MZC (reprint author), Oak Ridge Natl Lab, Div Chem Technol, 1 Bethel Valley Rd, 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 15 TC 89 Z9 90 U1 3 U2 47 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD MAY 1 PY 2000 VL 110 IS 1-2 SI SI BP 2 EP 14 DI 10.1016/S0032-5910(99)00262-4 PG 13 WC Engineering, Chemical SC Engineering GA 341VF UT WOS:000088611000002 ER PT J AU Sugama, T Cook, M AF Sugama, T Cook, M TI Poly(itaconic acid)-modified chitosan coatings for mitigating corrosion of aluminum substrates SO PROGRESS IN ORGANIC COATINGS LA English DT Review DE poly(itaconic acid); aluminum; water-insoluble ID RAY PHOTOELECTRON-SPECTROSCOPY; POLYMER SURFACES; ADHESION AB To make a water-insoluble chitosan (CS) biopolymer, the synthetic poly(itaconic acid) (PIA) polymer was added to graft it onto the Liner CS chains and to crosslink between the CS chains. The grafting and crosslinking reactions were generated by a strong chemical affinity between the NH2 groups in the CS and the COOH groups in the PLA, leading to the formation of amide bonds. When this polymer was applied as environmentally benign water-based coatings to an aluminum (Al) substrate by a simple dip-withdrawing method, the following three factors played an essential role in mitigating the rate of corrosion of the Al: first was the polymer's conformation containing hydrophobic amide bonds, together with a minimal amount of hydrophilic unreacted COOH in PIA and NH2 in CS; second was the lesser susceptibility of the coating films to moisture due to the enhanced degree of grafting and crosslinking; and third was the interactions at the interfaces between the grafted CS and the Al substrate, developing the formation of the -COO-Al Linkage. The PIA-grafted and -crosslinked CS polymer coating films generated from the proper proportions of PIA to CS included all these factors and displayed low ionic conductivity, thereby imparting a salt-spray resistance of 694 h for coated Al panels. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Brookhaven Natl Lab, Dept Appl Sci, Div Mat & Chem Sci, Upton, NY 11973 USA. Polytech Univ, Dept Chem, Brooklyn, NY 11201 USA. RP Brookhaven Natl Lab, Dept Appl Sci, Div Mat & Chem Sci, Upton, NY 11973 USA. NR 19 TC 36 Z9 37 U1 3 U2 27 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0300-9440 J9 PROG ORG COAT JI Prog. Org. Coat. PD MAY PY 2000 VL 38 IS 2 BP 79 EP 87 DI 10.1016/S0300-9440(00)00077-1 PG 9 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA 329LZ UT WOS:000087909600005 ER PT J AU Souers, PC Anderson, S Mercer, J McGuire, E Vitello, P AF Souers, PC Anderson, S Mercer, J McGuire, E Vitello, P TI JWL++: A simple reactive flow code package for detonation SO PROPELLANTS EXPLOSIVES PYROTECHNICS LA English DT Article AB JWL++ is a simple Reactive Flow model that includes time-dependent reaction in prompt detonation. It consists of a Murnahan unreacted equation of state, a JWL reacted EOS, a mixer for the two EOS's and a single-time-constant exponential rate. The mixing can be done by four ways, using either pressure or pressure plus artificial viscosity in the rate, and also using either an analytic function or a pressure equilibrator. The model reproduces the Size Effect and detonation front curvature. Detonation failure can also be induced. JWL++ propagates also through an arbitrary geometry in 3-D without the need for pre-run program burn calculations. It is slower than a JWL/program "Burn" but faster than "Ignition & Growth". C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Souers, PC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 20 TC 37 Z9 38 U1 0 U2 11 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0721-3115 J9 PROPELL EXPLOS PYROT JI Propellants Explos. Pyrotech. PD MAY PY 2000 VL 25 IS 2 BP 54 EP 58 DI 10.1002/(SICI)1521-4087(200004)25:2<54::AID-PREP54>3.0.CO;2-3 PG 5 WC Chemistry, Applied; Engineering, Chemical SC Chemistry; Engineering GA 316JX UT WOS:000087164600002 ER PT J AU Segelke, BW Forstner, M Knapp, M Trakhanov, SD Parkin, S Newhouse, YM Bellamy, HD Weisgraber, KH Rupp, B AF Segelke, BW Forstner, M Knapp, M Trakhanov, SD Parkin, S Newhouse, YM Bellamy, HD Weisgraber, KH Rupp, B TI Conformational flexibility in the apolipoprotein E amino-terminal domain structure determined from three new crystal forms: Implications for lipid binding SO PROTEIN SCIENCE LA English DT Article DE apolipoprotein E; lipid binding; MAD phasing; X-ray crystallography ID LDL RECEPTOR-BINDING; ALZHEIMERS-DISEASE; MYOCARDIAL-INFARCTION; PLASMA-LIPOPROTEINS; SIGNAL-TRANSDUCTION; AQUEOUS-SOLUTION; TYPE-4 ALLELE; ACID-SEQUENCE; APOPROTEIN-E; HEAD-INJURY AB An amino-terminal fragment of human apolipoprotein E3 (residues 1-165) has been expressed and crystallized in three different crystal forms under similar crystallization conditions. One crystal form has nearly identical cell dimensions to the previously reported orthorhombic (P2(1)2(1)2(1)) crystal form of the amino-terminal 22 kDa fragment of apoliporprotein E (residues 1-191). A second orthorhombic crystal form (P2(1)2(1)2(1) With cell dimensions differing from the first form) and a trigonal (P3(1)21) crystal form were also characterized. The structures of the first orthorhombic and the trigonal from were determined by seleno-methionine multiwavelength anomalous dispersion, and the structure of the second orthorhombic form was determined by molecular replacement using the structure from the trigonal form as a search model. A combination of modern experimental and computational techniques provided high-quality electron-density maps. which revealed new features of the apolipoprotein E structure, including an unambiguously traced loop connecting helices 2 and 3 in the four-helix bundle and a number of multiconformation side chains. The three crystal Terms contain a common intermolecular, antiparallel packing arrangement. The electrostatic complimentarity observed in this anti-parallel packing resembles the interaction of apolipoprotein E with the monoclonal antibody 2E8 and the low density lipoprotein receptor. Superposition of the model structures from all three crystal forms reveals flexibility and pronounced kinks in helices near one end of the four-helix bundle. This mobility at one end of the molecule provides new insights into the structural changes in apolipoprotein E that occur with lipid association. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Univ Calif San Francisco, Gladstone Inst Cardiovasc Dis, San Francisco, CA 94141 USA. Univ Calif San Francisco, Cardiovasc Res Inst, San Francisco, CA 94141 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Univ Calif San Francisco, Dept Pathol, San Francisco, CA 94141 USA. RP Rupp, B (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, L-452, Livermore, CA 94550 USA. RI Parkin, Sean/E-7044-2011 FU NCRR NIH HHS [RR01614]; NINDS NIH HHS [NS35939] NR 74 TC 42 Z9 44 U1 0 U2 4 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0961-8368 J9 PROTEIN SCI JI Protein Sci. PD MAY PY 2000 VL 9 IS 5 BP 886 EP 897 PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 317UM UT WOS:000087245400006 PM 10850798 ER PT J AU Martin, MC AF Martin, MC TI How to use a synchrotron for IR microscopy SO R&D MAGAZINE LA English DT Article C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RP Martin, MC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU CAHNERS-DENVER PUBLISHING CO PI OAK BROOK PA 2000 CLEARWATER DR, OAK BROOK, IL 60523-8809 USA SN 0746-9179 J9 R&D MAG JI R D Mag. PD MAY PY 2000 VL 42 IS 5 BP 105 EP 105 PG 1 WC Engineering, Industrial; Multidisciplinary Sciences SC Engineering; Science & Technology - Other Topics GA 325PN UT WOS:000087685000037 ER PT J AU Werst, DW Choure, SC Vinokur, EI Xu, LQ Trifunac, AD AF Werst, DW Choure, SC Vinokur, EI Xu, LQ Trifunac, AD TI Radiation chemistry in occluded phases: MCM-41 SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article DE MCM-41; radiolysis; heterogeneous chemistry; mesoporous; EPR ID BENZENE RADICAL CATIONS; ELECTRON-SPIN-RESONANCE; ION MOLECULE REACTIONS; RESOLUTION; ZEOLITES; EPR; SURFACES; MATRICES; RESISTS; SILICA AB Mixed-phase systems were designed by condensing hydrocarbons and halocarbons into the 30 Angstrom pores of the silica tube material, MCM-41. Radical cation probes, generated radiolytically at the phase interface with the silica wall or in the occluded phase inside the mesopores, were detected, as well as their paramagnetic reaction products, by variable-temperature EPR. Chemistry of radical cations at the phase interface and in such confined phases reveals the effects of energy transfer to solvent and geometric constraints on molecular packing and mobility. New, ordered forms of mesoporous silica offer many possibilities for studying the effects of nanoscale heterogeneity on radiation chemistry and on chemistry in general. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Werst, DW (reprint author), Argonne Natl Lab, Div Chem, 9700 Cass Ave, Argonne, IL 60439 USA. NR 22 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD MAY PY 2000 VL 58 IS 3 BP 223 EP 232 DI 10.1016/S0969-806X(99)00467-3 PG 10 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 318RK UT WOS:000087297500004 ER PT J AU Glass, WA AF Glass, WA TI William Carl Roesch (1923-1999) - In memoriam SO RADIATION RESEARCH LA English DT Biographical-Item C1 Pacific NW Natl Lab, Richland, WA 99352 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAY PY 2000 VL 153 IS 5 BP 607 EP 608 DI 10.1667/0033-7587(2000)153[0607:IM]2.0.CO;2 PN 1 PG 2 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 317BK UT WOS:000087204300017 ER PT J AU Griffin, GD Williams, MW Gailey, PC AF Griffin, GD Williams, MW Gailey, PC TI Cellular communication in clone 9 cells exposed to magnetic fields SO RADIATION RESEARCH LA English DT Article ID JUNCTIONAL INTERCELLULAR COMMUNICATION; NORMAL C3H/10T1/2 CELLS; ELECTROMAGNETIC-FIELDS; NEURITE OUTGROWTH; INHIBITION; GROWTH; ONCOGENE; GENE AB Magnetic-field exposure (45 Hz B(a.c.) over a Bur density range of 7.7 to 49.9 mu T r.m.s. with parallel B(d.c.) of 36.6 mu T) has been reported by Blackman and coworkers to inhibit gap junction intercellular communication in Clone 9 cells treated with chloral hydrate for 24 h prior to field exposure in accord with predictions of the ion parametric resonance model. The study reported here is an attempt to reproduce this effect. Baseline experiments showed that growth in culture and state of confluence at time of addition of chloral hydrate were comparable in both laboratories, PMA inhibited cell-cell communication in a dose-dependent manner, similar to the results of Blackman and coworkers, whereas cells in the present study were somewhat more sensitive to chloral hydrate than reported by Blackman and coworkers. A total of 38 exposure experiments were undertaken using a 45 Hz magnetic field with a Bur density of 23.8 mu T r.m.s., in parallel with a 36.6-mu T static magnetic field for 40 to 45 min, after pretreatment with 25 mM chloral hydrate for 24 h, In 14 unblinded experiments, a small but statistically significant effect of magnetic-field exposure was observed, but due to the subjective nature of the assay, it was deemed essential to carry out blinded experiments, The remaining 24 experiments were blinded. In 15 blinded experiments, cells purchased from the American Type Culture Collection and grown only in this laboratory were used, while in 9 experiments, the cells had originally been grown in Blackman's laboratory and were subsequently sent to this laboratory. There was no statistically significant effect of magnetic-field exposure on gap junction intercellular communication in these blinded experiments using either cell line. (C) 2000 Radiation Research Society. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Ohio Univ, Dept Phys & Astron, Athens, OH 45701 USA. Oak Ridge Natl Lab, Div Energy, Oak Ridge, TN 37831 USA. RP Griffin, GD (reprint author), Oak Ridge Natl Lab, Div Life Sci, POB 2008,MS-6101, Oak Ridge, TN 37831 USA. FU NIEHS NIH HHS [5 R03 ES08864-02] NR 41 TC 4 Z9 4 U1 0 U2 1 PU RADIATION RESEARCH SOC PI LAWRENCE PA 810 E TENTH STREET, LAWRENCE, KS 66044 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAY PY 2000 VL 153 IS 5 BP 690 EP 698 DI 10.1667/0033-7587(2000)153[0690:CCICCE]2.0.CO;2 PN 2 PG 9 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 317BL UT WOS:000087204400012 PM 10790294 ER PT J AU Orlova, AI Jardine, LJ AF Orlova, AI Jardine, LJ TI Immobilization of excess weapons plutonium SO RADIOCHEMISTRY LA English DT Article C1 Lobachevskii Nizhni Novgorod State Univ, Nizhnii Novgorod, Russia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Orlova, AI (reprint author), Lobachevskii Nizhni Novgorod State Univ, Nizhnii Novgorod, Russia. RI Orlova, Albina/A-1590-2014 OI Orlova, Albina/0000-0002-6397-6081 NR 0 TC 0 Z9 0 U1 0 U2 0 PU MAIK NAUKA/INTERPERIODICA PI NEW YORK PA C/O KLUWER ACADEMIC-PLENUM PUBLISHERS, 233 SPRING ST, NEW YORK, NY 10013-1578 USA SN 1066-3622 J9 RADIOCHEMISTRY+ JI Radiochemistry PD MAY-JUN PY 2000 VL 42 IS 3 BP 307 EP 310 PG 4 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear SC Chemistry GA 346VX UT WOS:000088892700019 ER PT J AU Baumann, TF Reynolds, JG Fox, GA AF Baumann, TF Reynolds, JG Fox, GA TI Polymer pendant crown thioethers: synthesis, characterization and Hg2+ extraction studies of polymer-supported thiacrowns ([14]aneS(4) and [17]aneS(5)) SO REACTIVE & FUNCTIONAL POLYMERS LA English DT Article DE polymer pendant ligand; thiacrown; toxic metal; metal extraction ID LIGAND CHEMISTRY; AQUEOUS-SOLUTION; MERCURY(II); IONS; PRECONCENTRATION; DIVINYLBENZENE; DERIVATIVES; SILVER(I); RECOVERY; COMPLEX AB We are interested in designing polymer-bound extractants fur Hg2+ remediation in mixed-waste streams. Towards this goal, we have synthesized novel polymer extractants where 2-aminomethylthiacrowns are immobilized on a polystyrene-divinylbenzene matrix through the pendant arm of the crowns. Reaction of 2,3-dimercapto-1-propanol with either 4,7-dithiadecane-1, 10-di-p-toluenesulfonate or 4,7, 10-trithiatridecane-1,13-di-p-toluenesulfonate generated the 2-hydroxymethylthiacrowns, 3 ([14]aneS(4)-OH) and 4 ([17]aneS(5)-OH). Treatment of the 2-hydroxymethylthiacrowns with thionyl chloride, followed by monomethylamine, produced the N-(methyl)-2-aminomethylthiacrowns, 5 [14]aneS(4)-(NRR2)-R-1) and 6 ([17]aneS(5)-N (RR2)-R-1) (R-1 =Me, R-2 = H). The thiacrown polymers were prepared through the copolymerization of a 4-vinylbenzyl-substituted aminomethylthiacrown, 7 ([14]aneS(4)-N (RR2)-R-1) or 8 ([17]aneS(5)-N (RR2)-R-1) (R-1 = Me, R-2 = 4-vinylbenzyl), with divinylbenzene, Extraction of Hg2+ from aqueous media using the [17]aneS(5) thiacrown polymer 10 with under a variety of conditions ([Hg2+] 4-200 ppm, pH 1.5-6.2) shows that the resin effectively and selectively removes Hg2+ ions from acidic aqueous solutions with extraction efficiency similar to 95%. Mercury recovery and polymer regeneration was also demonstrated using chloroform solutions of diphenylthiocarbazone to strip the bound Hg2+ from the resin. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Baumann, TF (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 27 TC 39 Z9 39 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1381-5148 J9 REACT FUNCT POLYM JI React. Funct. Polym. PD MAY PY 2000 VL 44 IS 2 BP 111 EP 120 DI 10.1016/S1381-5148(99)00085-1 PG 10 WC Chemistry, Applied; Engineering, Chemical; Polymer Science SC Chemistry; Engineering; Polymer Science GA 325KG UT WOS:000087674300003 ER PT J AU Ice, GE Chung, JS Lowe, W Williams, E Edelman, J AF Ice, GE Chung, JS Lowe, W Williams, E Edelman, J TI Small-displacement monochromator for microdiffraction experiments SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID RAY; RESOLUTION AB We describe the design, construction, and performance of the MHATT-CAT microdiffraction x-ray monochromator. This monochromator is specially engineered for x-ray microdiffraction experiments with a high brilliance undulator source. The monochromator passes a small emittance beam, suitable for focusing to submicron size with submilliradian divergence. Over its energy range of 8-22 keV the absolute energy calibration is better than 2 eV and scans of +/- 1 keV show no measurable hysterisis. The monochromator operates with a simple water-cooled first crystal and shows no measurable warm-up time. Horizontal linear bearings allow the monochromator crystals to be rapidly inserted or removed from the beam. Slits before and after the monochromator work to pass broad bandpass or monochromatic x-ray beams at the same vertical height. The monochromatic beam direction is adjusted so the monochromatic and broad bandpass beams are coaxial. The design and performance of the monochromator allows efficient collection of microdiffraction data when coupled to a nondispersive Kirkpatrick-Baez focusing mirror pair. (C) 2000 American Institute of Physics. [S0034-6748(00)01805-0]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. Howard Univ, Washington, DC 20059 USA. RP Ice, GE (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. EM icege@oml.gov NR 10 TC 29 Z9 29 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0034-6748 EI 1089-7623 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 2000 VL 71 IS 5 BP 2001 EP 2006 DI 10.1063/1.1150568 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 309XJ UT WOS:000086794300008 ER PT J AU Hamza, AV Barnes, AV Magee, E Newman, M Schenkel, T McDonald, JW Schneider, DH AF Hamza, AV Barnes, AV Magee, E Newman, M Schenkel, T McDonald, JW Schneider, DH TI Highly charged ion based time-of-flight emission microscope SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID MIRROR ELECTRON-MICROSCOPY; SLOW; COINCIDENCE; STATE AB An emission microscope using highly charged ions as the excitation source has been designed, constructed, and operated. A novel "acorn" objective lens has been used to simultaneously image electron and secondary ion emission. A resistive anode-position sensitive detector is used to determine the x-y position and time of arrival of the secondary events at the microscope image plane. Contrast in the image can be based on the intensity of the electron emission and/or the presence of particular secondary ions. Spatial resolution of better than 1 mu m and mass resolution m/Delta m of better than 400 were demonstrated. Background rejection from uncorrelated events of greater than an order of magnitude is also achieved. (C) 2000 American Institute of Physics. [S0034-6748(00)03105-1]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Hamza, AV (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 16 TC 11 Z9 11 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 2000 VL 71 IS 5 BP 2077 EP 2081 DI 10.1063/1.1150582 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 309XJ UT WOS:000086794300023 ER PT J AU Gillen, KT Celina, M Keenan, MR AF Gillen, KT Celina, M Keenan, MR TI Methods for predicting more confident lifetimes of seals in air environments SO RUBBER CHEMISTRY AND TECHNOLOGY LA English DT Article; Proceedings Paper CT Spring Meeting of the American-Chemical-Society Rubber Division CY APR 13-16, 1999 CL CHICAGO, ILLINOIS SP Amer Chem Soc, Rubber Div ID DIFFUSION-LIMITED OXIDATION; THERMALLY AGED ELASTOMERS; STRESS-RELAXATION; OXYGEN DIFFUSION; TIME DEVELOPMENT; EXTRAPOLATION; COMPRESSION; ARRHENIUS; POLYMERS; PROFILES AB We have been working for many years to develop improved methods for predicting the lifetimes of polymers exposed to air environments and have recently turned our attention to seal materials. This paper describes an extensive study on a butyl material using elevated temperature compression stress-relaxation (CSR) techniques in combination with conventional oven aging exposures. The results initially indicated important synergistic effects when mechanical strain is combined with oven aging, as well as complex, non-Arrhenius behavior of the CSR results. By combining modeling and experiments, we show that diffusion-limited oxidation (DLO) anomalies dominate traditional CSR experiments. A new CSR approach allows us to eliminate DLO effects and recover Arrhenius behavior. Furthermore, the resulting CSR activation energy (E-a) from 125 to 70 degrees C is identical to the activation energies for the tensile elongation and for the oxygen consumption rate of unstrained material over similar temperature ranges. This strongly suggests that the same underlying oxidation reactions determine both the unstrained and strained degradation rates. We therefore utilize our ultrasensitive oxygen consumption rare approach down to 23 degrees C to show that the CSR E-a likely remains unchanged when extrapolated below 70 degrees C, allowing more confident room temperature lifetime predictions for the butyl seal. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Gillen, KT (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 36 TC 37 Z9 38 U1 3 U2 15 PU AMER CHEMICAL SOC INC PI AKRON PA RUBBER DIV UNIV AKRON PO BOX 499, AKRON, OH 44309-0499 USA SN 0035-9475 J9 RUBBER CHEM TECHNOL JI Rubber Chem. Technol. PD MAY-JUN PY 2000 VL 73 IS 2 BP 265 EP 283 DI 10.5254/1.3547590 PG 19 WC Polymer Science SC Polymer Science GA 327NW UT WOS:000087800800009 ER PT J AU Nellis, WJ AF Nellis, WJ TI Making metallic hydrogen SO SCIENTIFIC AMERICAN LA English DT Editorial Material C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Nellis, WJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 3 TC 9 Z9 9 U1 0 U2 5 PU SCI AMERICAN INC PI NEW YORK PA 415 MADISON AVE, NEW YORK, NY 10017 USA SN 0036-8733 J9 SCI AM JI Sci.Am. PD MAY PY 2000 VL 282 IS 5 BP 84 EP 90 PG 7 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 306CN UT WOS:000086579100026 PM 11056992 ER PT J AU Barnett, MO Jardine, PM Brooks, SC Selim, HM AF Barnett, MO Jardine, PM Brooks, SC Selim, HM TI Adsorption and transport of uranium(VI) in subsurface media SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID SURFACE PRECIPITATION; SORPTION; URANYL; MONTMORILLONITE; SMECTITE; MINERALS; MODEL AB Uranium(VI) adsorption and transport in three natural, heterogeneous subsurface media were investigated in batch and column experiments. The rate of U(VI) adsorption to the natural samples was rapid over the first few hours of the experiments, and then slowed appreciably after 23 to 48 h. The adsorption of U(VI) to the samples was also nonlinear, suggesting a decreasing attraction for the surface with increased surface loading. The extent of adsorption on each of the media was strongly pH-dependent, increasing sharply as the pH increased from 4.5 to 5.5 and then decreasing sharply over the pH range 7.5 to 8.5 as the concentration of dissolved carbonate and U(VI)-carbonate complexes increased, The similarities in the pH-dependent behavior between the three materials despite differences in bulk mineralogy was likely due to the similar Fe contents of the materials. The transport of U(VI) through packed columns of the soils and sediments was significantly retarded but reversible. The local equilibrium assumption and the batch-measured adsorption isotherms dramatically underestimated the degree of retardation observed in the columns. The U(VI) displacement experiments were modeled with the one-dimensional advertive-dispersive equation and several different model formulations describing the interactions of U(VI) with the solid phase. These models were able to fit the observed breakthrough curves within 0.1 root mean square error of the initial concentration. C1 Auburn Univ, Dept Civil Engn, Auburn, AL 36849 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Louisiana State Univ, Dept Agron, Baton Rouge, LA 70803 USA. RP Barnett, MO (reprint author), Auburn Univ, Dept Civil Engn, 208 Harbert Engn Ctr, Auburn, AL 36849 USA. RI Brooks, Scott/B-9439-2012 OI Brooks, Scott/0000-0002-8437-9788 NR 30 TC 140 Z9 145 U1 5 U2 56 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD MAY-JUN PY 2000 VL 64 IS 3 BP 908 EP 917 PG 10 WC Soil Science SC Agriculture GA 356MD UT WOS:000089446300013 ER PT J AU Hagaman, EW Farrow, L Galipo, EG AF Hagaman, EW Farrow, L Galipo, EG TI Search for retrogressive reactions accompanying demineralization in native and air-oxidized coals SO SOLID STATE NUCLEAR MAGNETIC RESONANCE LA English DT Article; Proceedings Paper CT 218th American-Chemical-Society National Meeting CY AUG 22-26, 1999 CL NEW ORLEANS, LOUISIANA SP Amer Chem Soc DE coal; air oxidation; coal demineralization; polymerization; C-13 CP/MAS NMR ID C-13 NMR; OXIDATION AB This solid state C-13 NMR study confirms, for coals, and extends, for air-oxidized coals, the claim that the Bishop and Ward strong aqueous-acid coal demineralization procedure [M. Bishop, D.L. Ward, Fuel 37 (1958) 191.] does not lead to the formation of detectable levels of cross-links in the organic matrix of these materials. The study was prompted by the demonstration that polymerization accompanies strong acid demineralization in lignin, and the recognition that the chemical environment created in air-oxidized coals contains introduced reactive functionality similar to that in the lignin. In particular, both contain oxidized benzylic carbon functionality that can undergo acid-catalyzed polymerization reactions. For two coals of differing rank, no acid-induced cross-link formation has been observed in the pristine or air-oxidized coals, within the 5 parts per thousand (ppt) sensitivity of the NMR technique used in this study. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Hagaman, EW (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 15 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-2040 J9 SOLID STATE NUCL MAG JI Solid State Nucl. Magn. Reson. PD MAY PY 2000 VL 16 IS 1-2 SI SI BP 69 EP 75 DI 10.1016/S0926-2040(00)00056-4 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter; Spectroscopy SC Chemistry; Physics; Spectroscopy GA 311QE UT WOS:000086895000009 PM 10811431 ER PT J AU Malozemoff, AP Annavarapu, S Fritzemeier, L Li, Q Prunier, V Rupich, M Thieme, C Zhang, W Goyal, A Paranthaman, M Lee, DF AF Malozemoff, AP Annavarapu, S Fritzemeier, L Li, Q Prunier, V Rupich, M Thieme, C Zhang, W Goyal, A Paranthaman, M Lee, DF TI Low-cost YBCO coated conductor technology SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article; Proceedings Paper CT 4th European Conference on Applied Superconductivity CY SEP 14-17, 1999 CL SITGES, SPAIN ID ELECTRON-BEAM EVAPORATION; BIAXIALLY TEXTURED NI; BUFFER LAYERS; ALUMINATE FILMS; GROWTH; DEPOSITION; TAPES AB Deformation-textured non-silver substrates, and solution-based deposition of buffer and superconductor layers offer routes to a low-cost YBCO coated-conductor technology for high-temperature superconducting wire. Several significant steps towards such a technology are reported here: a solution-based Gd2O3 Seed buffer layer was deposited by a web-coating technique over a metre-length tape of deformation-textured nickel with excellent texture and uniformity. Also, short full-stack samples with YBCO performance up to 0.8 MA cm(-2) at 77 K were prepared at Oak Ridge National Laboratory (ORNL) and American Superconductor (ASC) using a CeO2/YSZ/CeO2 buffer sequence on textured nickel and a trifluoroacetate (TFA) precursor YBCO process; in this case the buffers are deposited by e-beam and magnetron sputtering. C1 Amer Superconductor, Westborough, MA 01581 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Malozemoff, AP (reprint author), Amer Superconductor, 2 Technol Dr, Westborough, MA 01581 USA. RI Paranthaman, Mariappan/N-3866-2015 OI Paranthaman, Mariappan/0000-0003-3009-8531 NR 26 TC 76 Z9 77 U1 1 U2 12 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 MAY PY 2000 VL 13 IS 5 BP 473 EP 476 DI 10.1088/0953-2048/13/5/308 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 322HL UT WOS:000087504100010 ER PT J AU Specht, ED Goyal, A Kroeger, DM AF Specht, ED Goyal, A Kroeger, DM TI Scaling of percolative current flow to long lengths in biaxially textured conductors SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; THICK-FILMS; DEPOSITION AB A random mixture of conducting and non-conducting sites or bonds on a two-dimensional lattice is used to model textured polycrystalline superconducting conductors in which high currents are carried only by low-angle grain boundaries. We calculate the frequency with which unfavourable configurations will significantly decrease current flow. For realistic distributions, in very narrow conductors (similar to 10 grains wide) critical current is reduced, sometimes to zero, over long lengths. For a typical conductor, 1 cm wide with 50 mu m grain size, fluctuations in critical current of less than 10% are expected for kilometre lengths. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Specht, ED (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Specht, Eliot/A-5654-2009 OI Specht, Eliot/0000-0002-3191-2163 NR 10 TC 37 Z9 38 U1 0 U2 1 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 MAY PY 2000 VL 13 IS 5 BP 592 EP 597 DI 10.1088/0953-2048/13/5/331 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 322HL UT WOS:000087504100033 ER PT J AU Blount, MA Simmons, JA Moon, JS Lyo, SK Wendt, JR Reno, JL AF Blount, MA Simmons, JA Moon, JS Lyo, SK Wendt, JR Reno, JL TI Magnetic anticrossing of 1D subbands in ballistic double quantum wires SO SUPERLATTICES AND MICROSTRUCTURES LA English DT Article; Proceedings Paper CT 3rd International Workshop on Surgaces and Interfaces in Mesoscopic Devices (SIMD 99) CY DEC 06-10, 1999 CL MAUI, HAWAII SP USN, Off Res, Univ Illinois, Beckman Inst DE quantum point contact; magnetoconductance; tunneling; anticrossing AB We study the low-temperature in-plane magnetoconductance of vertically coupled double quantum wires. Using a novel flip-chip technique, the wires are defined by two pairs of mutually aligned split gates on opposite sides of a less than or equal to 1 micron thick AlGaAs/GaAs double quantum well heterostructure. We observe quantized conductance steps due to each quantum well and demonstrate independent control of each 1D wire. A broad dip in the magnetoconductance at similar to 6 T is observed when a magnetic field is applied perpendicular to both the current and growth directions. This conductance dip is observed only when 1D subbands are populated in both the top and bottom constrictions. This data is consistent with a counting model whereby the number of subbands crossing the Fermi level changes with field due to the formation of an anticrossing in each pair of 1D subbands. (C) 2000 Academic Press. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. RP Simmons, JA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 8 TC 0 Z9 0 U1 1 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0749-6036 J9 SUPERLATTICE MICROST JI Superlattices Microstruct. PD MAY-JUN PY 2000 VL 27 IS 5-6 BP 463 EP 468 DI 10.1006/spmi.2000.0828 PG 6 WC Physics, Condensed Matter SC Physics GA 340AR UT WOS:000088511400031 ER PT J AU Thomas, EV Ge, NX AF Thomas, EV Ge, NX TI Development of robust multivariate calibration models SO TECHNOMETRICS LA English DT Article DE calibration maintenance; chemometrics; diffuse reflectance spectroscopy; robust experimental design; signal-response system ID PARAMETER DESIGN; INFRARED-SPECTROSCOPY; CHEMOMETRICS; INSTRUMENTS AB Multivariate calibration is frequently used for the quantitative analysis of a wide variety of materials using spectroscopy in the agricultural and food industries, manufacturing industries, medical sciences, and pharmaceutical industries. To date, most of the research activities in the multivariate calibration literature have focused on data analysis for model building and prediction with methods such as principal-components regression or partial least squares regression. As an alternative to focusing on data-analytic activities, we consider the ability of an experimental design to improve the robustness of the resulting calibration model. Through an example involving diffuse reflectance measurements, we illustrate how consideration of environmental and instrumental factors during the experimental design phase can result in a calibration model that is robust (against natural environmental and instrument variations) and easy to maintain. In this example, the analyte of interest produces a spectroscopic signal that is very weak in comparison to the environmental and instrumental factors. C1 Sandia Natl Labs, Stat & Human Factors Dept, Albuquerque, NM 87185 USA. Bristol Myers Squibb, Princeton, NJ 08543 USA. RP Thomas, EV (reprint author), Sandia Natl Labs, Stat & Human Factors Dept, POB 5800, Albuquerque, NM 87185 USA. NR 21 TC 29 Z9 29 U1 1 U2 6 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD MAY PY 2000 VL 42 IS 2 BP 168 EP 177 DI 10.2307/1271449 PG 10 WC Statistics & Probability SC Mathematics GA 337VK UT WOS:000088382200007 ER PT J AU Ristorcelli, JR Poje, AC AF Ristorcelli, JR Poje, AC TI Lagrangian covariance analysis of beta-plane turbulence SO THEORETICAL AND COMPUTATIONAL FLUID DYNAMICS LA English DT Article ID 2-DIMENSIONAL TURBULENCE; MEAN FLOWS; ROTATING SPHERE; TRANSPORT; CIRCULATION; DRIVEN; WAVES; DISPERSION; JETS AB The effects of Rossby wave-turbulence interactions on particle dispersion are investigated in a Lagrangian analysis of the potential vorticity equation. The analysis produces several exact statistical results for fluid particle dispersion in barotropic turbulence on a beta-plane. In the inviscid problem the first integral time scale of the meridional velocity is found to be zero, as might occur in pure wave processes, and the meridional particle dispersion is bounded. The second integral time scale, which determines the magnitude of the bound, is shown to depend explicitly on beta, the enstrophy and the energy of the meridional velocity. Expressions relating the autocorrelation of the vorticity to the autocorrelation of the meridional velocity are derived and the Lagrangian integral time scale of the relative vorticity is diagnostically related to the meridional velocity correlation. The applicability of these predictions is verified in a series of numerical simulations. For a range of beta values, the meridional extent of quasisteady alternating zonally averaged jets occurring in the numerical solutions scales with a length scale given by the the standard deviation of the meridional particle dispersion. C1 Univ Calif Los Alamos Natl Lab, Div 10, Los Alamos, NM 87545 USA. Brown Univ, Div Appl Math, Providence, RI 02912 USA. RP Ristorcelli, JR (reprint author), Univ Calif Los Alamos Natl Lab, Div 10, POB 1663, Los Alamos, NM 87545 USA. NR 30 TC 1 Z9 1 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0935-4964 J9 THEOR COMP FLUID DYN JI Theor. Comput. Fluid Dyn. PD MAY PY 2000 VL 14 IS 1 BP 1 EP 20 DI 10.1007/s001620050122 PG 20 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 322PH UT WOS:000087517600001 ER PT J AU Burr, TL AF Burr, TL TI Quasi-equilibrium theory for the distribution of rare alleles in a subdivided population: Justification and implications SO THEORETICAL POPULATION BIOLOGY LA English DT Article ID GENE FLOW; NEUTRAL ALLELES; SAMPLING THEORY AB Th is paper examines a quasi-equilibrium theory of rare alleles for subdivided populations that follow an island-model version of the Wright-Fisher model of evolution. All mutations are assumed to create new alleles. We present four results: (1) conditions for the theory to apply are formally established using properties of the moments of the binomial distribution; (2) approximations currently in the literature can be replaced with exact results that are in better agreement with our simulations; (3) a modified maximum likelihood estimator of migration rate exhibits the same good performance on island-model data or on data simulated from the multinomial mixed with the Dirichlet distribution, and (4) a connection between the rare-allele method and the Ewens Sampling Formula for the infinite-allele mutation model is made. This introduces a new and simpler proof for the expected number of alleles implied by the Ewens Sampling Formula. (C) 2000 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Burr, TL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 19 TC 3 Z9 3 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0040-5809 J9 THEOR POPUL BIOL JI Theor. Popul. Biol. PD MAY PY 2000 VL 57 IS 3 BP 297 EP 306 DI 10.1006/tpbi.2000.1453 PG 10 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 320QG UT WOS:000087411400009 PM 10828221 ER PT J AU Hubbard, KM Espinoza, BF AF Hubbard, KM Espinoza, BF TI Corrosion-resistant erbium oxide coatings by organometallic chemical vapor deposition SO THIN SOLID FILMS LA English DT Article DE chemical vapor deposition; rare-earth oxide; erbia; corrosion; plutonium ID FILMS AB An oganometallic chemical vapor deposition (OMCVD) process was developed for the preparation of protective erbium oxide coatings resistant to corrosion by liquid plutonium. The coatings were deposited from the precursor compound Er(tmhd)(3) using a standard hot-wall reactor. The substrates used for process development were 304 stainless-steel flats; coatings were subsequently deposited on the internal surfaces of high-aspect-ratio tubular parts, as well as a variety of curved samples. The coatings have the correct oxygen/erbium ratio, and small concentrations of carbon and hydrogen impurities. The impurities are present in the form of unreacted or partially-reacted precursor molecules, presumably concentrated at the grain boundaries of the material. The films are polycrystalline with a grain size of 40-50 nm, and exhibit excellent adhesion and mechanical toughness. The small grain size and the resultant favorable mechanical properties may be attributable in part to the presence of the organic fragments at the grain boundaries. Coatings deposited on stainless-steel hats are resistant to corrosion by liquid plutonium, although an erbia-thickness threshold is observed. The failure mechanism for samples with thicknesses below the threshold value is most likely related to flaws in the film morphology, for example large pinholes, rather than grain-boundary attack. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hubbard, KM (reprint author), Univ Calif Los Alamos Natl Lab, Polymers & Coatings MST-7,POB 1663,Mail Stop 1663, Los Alamos, NM 87545 USA. NR 14 TC 32 Z9 33 U1 0 U2 3 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 MAY 1 PY 2000 VL 366 IS 1-2 BP 175 EP 180 DI 10.1016/S0040-6090(00)00720-3 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 314VT UT WOS:000087078800030 ER PT J AU van Birgelen, APJM Chou, BJ Renne, RA Grumbein, SL Roycroft, JH Hailey, JR Bucher, JR AF van Birgelen, APJM Chou, BJ Renne, RA Grumbein, SL Roycroft, JH Hailey, JR Bucher, JR TI Effects of glutaraldehyde in a 2-year inhalation study in rats and mice SO TOXICOLOGICAL SCIENCES LA English DT Article; Proceedings Paper CT 38th Annual Meeting of the Society-for-Toxicology CY MAR 14-18, 1999 CL NEW ORLEANS, LOUISIANA SP Soc Toxicol DE glutaraldehyde; toxicity; carcinogenicity; nose ID ZERO DOSE CONTROL; BODY-WEIGHT; RESPIRATORY-TRACT; B6C3F(1) MICE; LONG-TERM; FORMALDEHYDE; TOXICITY; CARCINOGENICITY; ACETALDEHYDE; ALDEHYDES AB Whole-body inhalation toxicology and carcinogenicity studies were performed with the widely used fixative and cold-sterilant glutaraldehyde. Groups of 50 male and female F344/N rats and B6C3F(1) mice were exposed to glutaraldehyde (rats: 0, 250, 500, or 750 ppb; mice: 0, 62.5, 125, or 250 ppb)6 h/day, 5 days/week, for 104 weeks. Survival of 500- and 750-ppb female rats was less than that of controls. Mean body weights of all exposed groups of male rats, 500- and 750-ppb female rats, and 250-ppb female mice were generally less than those of controls. No exposure-related neoplastic lesions were observed in either rats or mice. Non-neoplastic lesions were limited primarily to the most anterior region of the nasal cavity. In rats, hyperplasia and inflammation of the squamous epithelium; hyperplasia, goblet cell hyperplasia, inflammation, and squamous metaplasia of the respiratory epithelium; and hyaline degeneration of the olfactory epithelium were observed. In mice, the nasal lesions were qualitatively similar to those in rats. Squamous metaplasia of the respiratory epithelium was observed in both sexes of mice while female mice also had inflammation and hyaline degeneration of the respiratory epithelium. In contrast to the nasal carcinogen formaldehyde, no neoplastic lesions were observed after inhalation exposure to glutaraldehyde. However, exposure to glutaraldehyde resulted in considerable non-neoplastic lesions in the noses of rats and mice. C1 NIEHS, Res Triangle Pk, NC 27709 USA. Battelle Pacific NW, Richland, WA USA. RP van Birgelen, APJM (reprint author), Hoffmann La Roche Inc, Bldg 100,340 Kingsland St, Nutley, NJ 07110 USA. NR 55 TC 11 Z9 11 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1096-6080 J9 TOXICOL SCI JI Toxicol. Sci. PD MAY PY 2000 VL 55 IS 1 BP 195 EP 205 DI 10.1093/toxsci/55.1.195 PG 11 WC Toxicology SC Toxicology GA 310FH UT WOS:000086815500022 PM 10788574 ER PT J AU Chandler, DP Brockman, FJ Holman, DA Grate, JW Bruckner-Lea, CJ AF Chandler, DP Brockman, FJ Holman, DA Grate, JW Bruckner-Lea, CJ TI Renewable microcolumns for solid-phase nucleic acid separations and analysis from environmental samples SO TRAC-TRENDS IN ANALYTICAL CHEMISTRY LA English DT Article DE flow injection; sequential injection; DNA; renewable microcolumn; sample preparation; super-paramagnetic bead; microparticle ID FLOW-INJECTION; IMMUNOMAGNETIC SEPARATION; ESCHERICHIA-COLI; DRUG DISCOVERY; MICROARRAYS; CELL; HYBRIDIZATION; SPORES; FOOD AB This article summarizes the convergence of sequential injection-renewable separation columns (SI-RSC) and techniques with nucleic acid analysis at the Pacific Northwest National Laboratory. New renewable microcolumn designs, functional principles and their analytical and practical utility are presented within the context of automated nucleic acid extraction and purification from environmental samples. (C) 2000 Published by Elsevier Science B.V. C1 Pacific NW Lab, Environm Microbiol Grp, Richland, WA 99352 USA. Pacific NW Lab, Chem Sensors & Microanalyt Syst, Richland, WA 99352 USA. RP Chandler, DP (reprint author), Pacific NW Lab, Environm Microbiol Grp, POB 999,Mail Stop P7-50, Richland, WA 99352 USA. NR 23 TC 35 Z9 35 U1 0 U2 1 PU ELSEVIER SCIENCE LONDON PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0165-9936 J9 TRAC-TREND ANAL CHEM JI Trac-Trends Anal. Chem. PD MAY PY 2000 VL 19 IS 5 BP 314 EP 321 DI 10.1016/S0165-9936(99)00213-7 PG 8 WC Chemistry, Analytical SC Chemistry GA 309CR UT WOS:000086750500009 ER PT J AU Wilson, KB Baldocchi, DD Hanson, PJ AF Wilson, KB Baldocchi, DD Hanson, PJ TI Spatial and seasonal variability of photosynthetic parameters and their relationship to leaf nitrogen in a deciduous forest SO TREE PHYSIOLOGY LA English DT Article DE A/C-i curve; drought; gas exchange; leaf age; maple; oak ID PETRAEA MATT LIEBL; NORTHERN RED OAK; GAS-EXCHANGE; USE EFFICIENCY; STOMATAL CONDUCTANCE; CO2 ASSIMILATION; CARBON GAIN; NET PHOTOSYNTHESIS; FIELD CONDITIONS; PHOTOSYSTEM-II AB We used gas exchange techniques to estimate maximum rate of carboxylation (V-cmax), a measure of photosynthetic capacity, in the understory and upper crown of a closed deciduous forest over two seasons. There was extensive variability in photosynthetic capacity as a result of vertical canopy position, species type, leaf age and drought. Photosynthetic capacity was greater in oaks than in maples and greater in the overstory than in the understory. Parameter V-cmax was maximal early in the season but declined slowly throughout most of the summer, and then more rapidly during senescence. There was also an apparent decline during drought in some trees. Variability in V-cmax as a result of species or vertical canopy gradients was described well by changes in leaf nitrogen per unit area (N-a). However, temporal changes in V-cmax were often poorly correlated with leaf nitrogen, especially in spring and summer and during drought. This poor correlation may be the result of a seasonally dependent fractional allocation of leaf nitrogen to Rubisco; however, we could not discount Rubisco inactivation, patchy stomatal closure or changes in mesophyll resistance. Consequently, when a single annual regression equation of V-cmax versus N-a was used for this site, there were substantial errors in the temporal patterns in V-cmax that will inevitably result in modeling errors. C1 NOAA, Atmospher Turbulence & Diffus Div, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Wilson, KB (reprint author), NOAA, Atmospher Turbulence & Diffus Div, POB 2456, Oak Ridge, TN 37831 USA. RI Hanson, Paul J./D-8069-2011; Baldocchi, Dennis/A-1625-2009 OI Hanson, Paul J./0000-0001-7293-3561; Baldocchi, Dennis/0000-0003-3496-4919 NR 58 TC 215 Z9 224 U1 8 U2 43 PU HERON PUBLISHING PI VICTORIA PA 202, 3994 SHELBOURNE ST, VICTORIA, BC V8N 3E2, CANADA SN 0829-318X J9 TREE PHYSIOL JI Tree Physiol. PD MAY PY 2000 VL 20 IS 9 BP 565 EP 578 PG 14 WC Forestry SC Forestry GA 315JV UT WOS:000087111300001 ER PT J AU Kestel, BJ AF Kestel, BJ TI Preparation of damage-free glass TEM specimens SO ULTRAMICROSCOPY LA English DT Article DE glass NBS and ARM TEM specimens; damage-free jet polishing; automatic polishing termination AB A jet polishing technique to chemically thin glass specimens for transmission electron microscopy (TEM) after a preliminary mechanical dimpling step has been developed. Slightly modified commercial equipment is used with automatic optical termination of the polishing process to produce foils exhibiting large, high quality, electron transparent regions. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Kestel, BJ (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 2 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD MAY PY 2000 VL 83 IS 1-2 BP 61 EP 66 DI 10.1016/S0304-3991(99)00173-4 PG 6 WC Microscopy SC Microscopy GA 309BP UT WOS:000086747700006 ER PT J AU Bajt, S Barty, A Nugent, KA McCartney, M Wall, M Paganin, D AF Bajt, S Barty, A Nugent, KA McCartney, M Wall, M Paganin, D TI Quantitative phase-sensitive imaging in a transmission electron microscope SO ULTRAMICROSCOPY LA English DT Article DE holography; exit wave reconstruction; data processing/image processing ID HOLOGRAPHY; RESOLUTION; FILMS AB This paper presents a new technique for forming quantitative phase and amplitude electron images applicable to a conventional transmission electron microscope. With magnetised cobalt microstructures used as a test object, we use electron holography to obtain an independent measurement of the phase shift. After a suitable calibration of the microscope, we obtain quantitative agreement of the phase shift imposed on the 200 keV electrons passing through the sample. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Melbourne, Sch Phys, Melbourne, Vic 3010, Australia. Univ Calif Lawrence Livermore Natl Lab, Informat Sci & Technol Program, Livermore, CA 94550 USA. Arizona State Univ, Ctr Solid State Sci, Tempe, AZ 85287 USA. RP Nugent, KA (reprint author), Univ Melbourne, Sch Phys, Melbourne, Vic 3010, Australia. RI paganin, david/B-9717-2009; Bajt, Sasa/G-2228-2010; Nugent, Keith/J-2699-2012; Barty, Anton/K-5137-2014; Nugent, Keith/I-4154-2016 OI Nugent, Keith/0000-0003-1522-8991; Barty, Anton/0000-0003-4751-2727; Nugent, Keith/0000-0002-4281-3478 NR 16 TC 113 Z9 116 U1 2 U2 21 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD MAY PY 2000 VL 83 IS 1-2 BP 67 EP 73 DI 10.1016/S0304-3991(99)00174-6 PG 7 WC Microscopy SC Microscopy GA 309BP UT WOS:000086747700007 ER PT J AU Kaduchak, G Sinha, DN Lizon, DC Keleher, MJ AF Kaduchak, G Sinha, DN Lizon, DC Keleher, MJ TI A non-contact technique for evaluation of elastic structures at large stand-off distances: applications to classification of fluids in steel vessels (vol 37, 531, 2000) SO ULTRASONICS LA English DT Correction C1 Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Kaduchak, G (reprint author), Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, POB 1663, Los Alamos, NM 87545 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0041-624X J9 ULTRASONICS JI Ultrasonics PD MAY PY 2000 VL 37 IS 9 BP 657 EP 657 DI 10.1016/S0041-624X(00)00010-X PG 1 WC Acoustics; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Radiology, Nuclear Medicine & Medical Imaging GA 316ZZ UT WOS:000087199800006 ER PT J AU Brown, GO Hsieh, HT Lucero, DA AF Brown, GO Hsieh, HT Lucero, DA TI Evaluation of laboratory dolomite core sample size using representative elementary volume concepts SO WATER RESOURCES RESEARCH LA English DT Article ID POROUS-MEDIA; COMPUTERIZED-TOMOGRAPHY; SOIL; MACROPORES AB The adequacy for laboratory testing of four dolomite cores from the Culebra Dolomite of the Rustler Formation at the Waste Isolation Pilot Plant near Carlsbad, New Mexico, were evaluated using representative elementary volume (REV) theory. Gamma ray computerized tomography created three-dimensional grids of bulk density and macropore index over volumes from 1.4 x 10(-7) to 1.6 L. Three different methods for both volume averaging and REV analysis were applied and compared. Both density and macropore index converged to single values with increasing volume, which meets the most common qualitative definition of a REV. Statistical test results for the relatively homogeneous samples indicate that volumes larger than 1 to 7 mt have constant properties. Contrarily, a highly varied sample required 250 and 373 mL to achieve invariant density and macropore characteristics, respectively. Prismatic volume averaging was found to be better than slice averaging, while a qualitative test for the REV provided similar results as a rigorous statistical method. All cores were larger than the REV but were significantly different from one another. This implies that multiple cores are necessary to determine the entire range of transport properties within the rock. C1 Oklahoma State Univ, Dept Agr & Biosyst Engn, Stillwater, OK 74078 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Brown, GO (reprint author), Oklahoma State Univ, Dept Agr & Biosyst Engn, 219 Ag Hall, Stillwater, OK 74078 USA. RI Brown, Glenn/H-4354-2012 NR 23 TC 22 Z9 24 U1 0 U2 7 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 MAY PY 2000 VL 36 IS 5 BP 1199 EP 1207 DI 10.1029/2000WR900017 PG 9 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 310ET UT WOS:000086814100004 ER PT J AU Salve, R Wang, JSY Tokunaga, TK AF Salve, R Wang, JSY Tokunaga, TK TI A probe for measuring wetting front migration in rocks SO WATER RESOURCES RESEARCH LA English DT Article AB To facilitate investigations of flow dynamics in unsaturated fractured rocks, we have designed a probe to qualitatively monitor saturation changes in borehole environments. This flexible probe is able to fit the cylindrical shape of boreholes and requires no backfill. Field results suggest that the design of this electrical resistivity probe (ERP) is suitable for determining changes in relative wetness along boreholes in unsaturated fractured rock environments. The performance of these probes was compared with that of psychrometers under a variety of tests; these probes were found to be significantly cheaper in addition to providing data that had a greater spatial and temporal resolution. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Salve, R (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,Mail Stop 14-116, Berkeley, CA 94720 USA. RI Tokunaga, Tetsu/H-2790-2014 OI Tokunaga, Tetsu/0000-0003-0861-6128 NR 9 TC 8 Z9 8 U1 0 U2 3 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 MAY PY 2000 VL 36 IS 5 BP 1359 EP 1367 DI 10.1029/2000WR900022 PG 9 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 310ET UT WOS:000086814100020 ER PT J AU Gang, O Ocko, BM Wu, XZ Sirota, EB Deutsch, M AF Gang, O Ocko, BM Wu, XZ Sirota, EB Deutsch, M TI Surface structure tuning in alcohol melts by bulk additives SO COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS LA English DT Article; Proceedings Paper CT 15th European Chemistry at Interfaces Conference CY OCT 18-22, 1998 CL JERUSALEM, ISRAEL SP Israel Minist Sci, Israel Foreign Minist, Hebrew Univ Jerusalem DE surface freezing; pure alcohol melts; bulk additives; monolayer-bilayer surface phase transition ID LIQUID NORMAL-ALKANES; PHASES AB Surface freezing, i.e. the formation of a solid bilayer at the surface of a pure alcohol melt above the freezing temperature, was recently discovered. We demonstrate here that the structure of the bilayer can be influenced by specific bulk additives. Two different additives, able to form hydrogen bonds (water) and both hydrogen bonds and van der Waals interactions (alpha,omega-diols), are used. The surface layer's structure is studied by surface-specific X-ray methods. We find that water swells the bilayer by intercalation into its center at a molecular water:alcohol ratio of similar to 1:2. For the diolated alcohols a reversible monolayer-bilayer surface phase transition is observed, the first of its kind for surface-frozen layers. A continuous decrease of the molecular tilt with increasing diol concentration is also found for the tilted bilayer phases. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. IBM, Almaden Res Ctr, San Jose, CA 95120 USA. Exxon Res & Engn Co, Annandale, NJ 08801 USA. RP Gang, O (reprint author), Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. RI Sirota, Eric/A-7633-2009 NR 15 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-7757 J9 COLLOID SURFACE A JI Colloid Surf. A-Physicochem. Eng. Asp. PD APR 30 PY 2000 VL 164 IS 1 BP 55 EP 61 DI 10.1016/S0927-7757(99)00392-1 PG 7 WC Chemistry, Physical SC Chemistry GA 286KY UT WOS:000085446200008 ER PT J AU Harnisch, JA Angelici, RJ AF Harnisch, JA Angelici, RJ TI Gold and platinum benzenehexathiolate complexes as large templates for the synthesis of 12-coordinate polyphosphine macrocycles SO INORGANICA CHIMICA ACTA LA English DT Article DE benzenehexathiolate complexes; templated synthesis; phosphine macrocycle; gold complexes; platinum complexes ID COORDINATED LIGANDS; CRYSTAL-STRUCTURES; CROWN ETHERS; 1,5,9-TRIPHOSPHACYCLODODECANE; PALLADIUM(II); ANALOGS; ALKYL AB A general strategy for the synthesis of large-ring, poly-donor macrocycles using multi-metal ion templates is outlined. This strategy is illustrated in the design and synthesis of the hexanuclear (divinyl)(phenyl)phosphine gold complex of benzenehexathiolate, {[(C2H3)(2)(Ph)P]Au}(6)(C6S6) (1), which undergoes macrocycle formation upon reaction with PhPH2 in the presence of AIBN (Scheme 1). NMR spectra (H-1 and P-31) and elemental analyses indicate that the resulting macrocycle is a 36-membered ring containing 12 phosphorus donors, six of which are coordinated to the six Au atoms in the Au-6(C6S6) core. A series of tri-platinum complexes, (P boolean AND P)Pt](3)(C6S6) (16-19), where (P boolean AND P) is a bidentate phosphine ligand, with three (P boolean AND P)Pt-II units coordinated to a C6S66- core, were also prepared as models for templated formation of other poly-phosphorus macrocycles. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Angelici, RJ (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 59 TC 20 Z9 20 U1 0 U2 15 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0020-1693 J9 INORG CHIM ACTA JI Inorg. Chim. Acta PD APR 30 PY 2000 VL 300 BP 273 EP 279 DI 10.1016/S0020-1693(99)00552-6 PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 320WA UT WOS:000087422800034 ER PT J AU Bakac, A Butkovic, V Espenson, JH Orhanovic, M AF Bakac, A Butkovic, V Espenson, JH Orhanovic, M TI Concurrent homolysis, beta-elimination, and hydrolysis of macrocyclic alkylchromium complexes SO INORGANICA CHIMICA ACTA LA English DT Article DE alkylchromium; homolysis; hydrolysis; beta-elimination; kinetics ID CARBON BOND; ALKYL-HALIDES; MECHANISM; KINETICS; REACTIVITY; RADICALS AB The complexes L-1(H2O)CrR2+ (L-1=[14]aneN(4)) undergo homolytic chromium-carbon bond cleavage in aqueous solutions (R = CHMed(2), k = 0.003 s (- 1); CH(Me)(Et), 0.013; CH(Et)(2), 0.047) much more rapidly than the complexes in the aqua series, (H2O)(5)CrR2+. The hydrolysis, on the other hand, is much slower for the macrocyclic complexes. Both effects are discussed in terms of the steric congestion at the reaction site and the availability of coordinated molecules of water cis to the alkyl group. The complex L-1(H2O)CrCH(CH3)(2)(2+) also undergoes beta-elimination with a kinetic isotope effect of similar to 1.7. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Rudjer Boskovic Inst, Zagreb 10000, Croatia. RP Bakac, A (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 26 TC 1 Z9 1 U1 1 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0020-1693 J9 INORG CHIM ACTA JI Inorg. Chim. Acta PD APR 30 PY 2000 VL 300 BP 280 EP 284 DI 10.1016/S0020-1693(99)00569-1 PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 320WA UT WOS:000087422800035 ER PT J AU Albinati, A Chaloupka, S Currao, A Klooster, WT Koetzle, TF Nesper, R Venanzi, LM AF Albinati, A Chaloupka, S Currao, A Klooster, WT Koetzle, TF Nesper, R Venanzi, LM TI Structural studies of the hydride-bridged iridium gold complexes 'IrHm{CH3C(CH2PPh2)(3)}{Au(PR3)}(n)' SO INORGANICA CHIMICA ACTA LA English DT Article DE structural studies; hydride-bridged complexes; iridium gold complexes; trigold cluster ID TRANSITION-METAL COMPLEXES; NEUTRON-DIFFRACTION; CLUSTER COMPLEXES; AG-IR; LIGANDS; ELIMINATION; CRYSTAL; ALCOHOL AB The X-ray crystal structure of [{(triphos)H(3-x)Ir}(mu-H)(x) {Au(PR3)}][PF6] (triphos = CH3C(CH2PPh2)(3), x = 2) shows that the gold atom builds two almost equal Ir-H-Au bridges with the he'IrH3(triphos)' building block. The Ir-H-Au bridging parameters are typical of three-center-two-electron interactions. The X-ray crystal structure of [{(triphos)H(3-y)Ir}(mu-H)(y) {Au(PR3)}(2)][PF6](2) shows that each gold atom builds two Ir(mu(2)-H)Au bridges with the three hydrides of the 'IrH3(triphos)' building block; one Ir(mu(3)-H)Au-2 bridge is also present (y = 3). The relative positions of the Ir, H, Au and P atoms show that typical three-center-two-electron interactions predominate in this compound, in which there is no direct Au-Au bonding. The neutron diffraction structure of [{(triphos)Ir}(mu-H)(2){Au(PPh3)}(3)][PF6](2) confirms the earlier hypothesis that only two of the three Ir-Au edges are associated with a hydride with formation of Ir(mu(2)-H)Au bridges. The presence or absence of the latter ligand changes the Ir-Au distance only marginally, in contrast to the general trend in hydride clusters. It is shown that the formation of a 'classical' cluster in this set of compounds requires a quadrimetallic unit and the two additional electrons generated by loss of a proton from an Ir-fl bond in the trication [{(triphos)Ir (mu(2)-H)(3){Au(PR3)}(3)}(3+). (C) 2000 Elsevier Science S.A. All rights reserved. C1 ETH Zurich, Anorgan Chem Lab, CH-8092 Zurich, Switzerland. Univ Milan, Ist Chim Farmaceut, I-20131 Milan, Italy. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Venanzi, LM (reprint author), ETH Zurich, Anorgan Chem Lab, CH-8092 Zurich, Switzerland. RI Albinati, Alberto/I-1262-2015 OI Albinati, Alberto/0000-0002-8779-3327 NR 49 TC 7 Z9 7 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0020-1693 J9 INORG CHIM ACTA JI Inorg. Chim. Acta PD APR 30 PY 2000 VL 300 BP 903 EP 911 DI 10.1016/S0020-1693(00)00004-9 PG 9 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 320WA UT WOS:000087422800106 ER PT J AU Stolyarov, VV Zhu, YT Lowe, TC Islamgaliev, RK Valiev, RZ AF Stolyarov, VV Zhu, YT Lowe, TC Islamgaliev, RK Valiev, RZ TI Processing nanocrystalline Ti and its nanocomposites from micrometer-sized Ti powder using high pressure torsion SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE nanocrystalline; microstructure; high pressure torsion ID SEVERE PLASTIC-DEFORMATION; CHANNEL ANGULAR EXTRUSION; MECHANICAL-BEHAVIOR; CERAMIC POWDERS; GRAIN-SIZE; CONSOLIDATION; COPPER; ALLOYS; METALS; MICROSTRUCTURE AB Nanocrystalline Ti and Ti-TiO2 nanocomposites were produced by high pressure torsion (HPT) of precompacts of Ti powder (21 mu m) and its mixture with TiO2 powder (36 nm). Effects of processing temperature and pressure on material density and microhardness were systematically studied. The HPT process simultaneously consolidated the TI and Ti-TiO2 powders and refined the grains to nanometer size. The microstructure of as-processed samples contained high dislocation density, high internal stress, high angle, non-equilibrium grain boundaries, and texture. Mechanical properties such as microhardness increased with increasing density. Tensile testing showed that the as-processed materials were very brittle. High pressure torsion was found to be a promising technique for producing nanocrystalline materials from micrometer-sized metallic powders. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Ufa State Aviat Tech Univ, Inst Phys Adv Mat, Ufa 450000, Russia. RP Zhu, YT (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Zhu, Yuntian/B-3021-2008 OI Zhu, Yuntian/0000-0002-5961-7422 NR 45 TC 81 Z9 85 U1 0 U2 17 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD APR 30 PY 2000 VL 282 IS 1-2 BP 78 EP 85 DI 10.1016/S0921-5093(99)00764-9 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 295LB UT WOS:000085966600011 ER PT J AU Holden, TM Holt, RA Tome, CN AF Holden, TM Holt, RA Tome, CN TI Intergranular strains in Inconel-600 SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE neutron diffraction; EPSC model; tensile strain AB Neutron diffraction measurements of the residual intergranular strains generated by uniaxial plastic deformations of + 5.6 and - 6.0% in samples of Inconel-600 are presented as strain pole-figures for the (111), (002), (220), and (113) reflections of the face-centered cubic structure. The results agree with earlier unusual results obtained for Inconel-600 and also show that the intergranular strains change sign when the sign of the plastic deformation is reversed. The results provide a test of the elasto-plastic self-consistent model with which they are critically compared. Published by Elsevier Science S.A. C1 Univ Calif Los Alamos Natl Lab, MST Div, Los Alamos, NM 87545 USA. Natl Res Council Canada, Steacie Inst Mol Sci, Neutron Program Mat Res, Chalk River, ON K0J 1J0, Canada. AECL Res, Chalk River Labs, Chalk River, ON K0J 1J0, Canada. RP Tome, CN (reprint author), Univ Calif Los Alamos Natl Lab, MST Div, POB 1663, Los Alamos, NM 87545 USA. RI Tome, Carlos/D-5058-2013 NR 10 TC 19 Z9 19 U1 0 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD APR 30 PY 2000 VL 282 IS 1-2 BP 131 EP 136 DI 10.1016/S0921-5093(99)00774-1 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 295LB UT WOS:000085966600018 ER PT J AU O'Rourke, M Diskin, MG Sreenan, JM Roche, JF AF O'Rourke, M Diskin, MG Sreenan, JM Roche, JF TI The effect of dose and route of oestradiol benzoate administration on plasma concentrations of oestradiol and FSH in long-term ovariectomised heifers SO ANIMAL REPRODUCTION SCIENCE LA English DT Article DE cattle; endocrinology; ovariectomy; oestradiol; FSH ID FOLLICLE-STIMULATING-HORMONE; GONADOTROPIN-RELEASING-HORMONE; ESTROUS-CYCLE; LUTEINIZING-HORMONE; DOMINANT FOLLICLE; OVARIAN-FUNCTION; WAVE DYNAMICS; ESTRADIOL; CATTLE; COWS AB Oestradiol (E-2) suppresses FSH and affects follicle wave dynamics in cattle. However, neither the optimum dose of ODB required to suppress FSH nor the effect of route of ODB administration on blood concentrations of E-2 are known; hence, the aim of this experiment was to answer these questions. Ovariectomised heifers received Progesterone Releasing Intravaginal Device (PRID) for 7 days, and 4 days later heifers received one of eight ODB treatments at second PRID insertion as follows; (1) 0.0 mg (Control; n = 3), (2) 0.5 mg (n = 4), (3) 1.0 mg (n = 4), (4) 2.5 mg (n = 6), (5) 5.0 mg (n = 4), (6) 10.0 mg (n = 4), (7) 5.0 mg (n = 4), and (8) 10.0 mg (n = 5). For treatments 2-6 inclusive, ODB was administered intramuscularly in oil, while for treatments 7 and 8, the ODB in powder form was administered topically in the vagina by gelatine capsule attached to the PRID. Blood samples were collected every 6 h for the first 48 h, every 12 h for the next 48 h, and twice daily for a further 6 days. The interval from ODB administration to peak E-2 concentration was similar (P > 0.05) for treatments 2-6 where ODB was administered intramuscularly (mean 13.4 +/- 1.24 h), and was longer (P < 0.05) for the intravaginal capsule treatments (mean 25.5 +/- 2.84 h). Plasma concentrations of E-2 increased with increasing intramuscular dose of ODB injected, (plasma E-2 = -0.237 + 16.109 (dose) - 0.74 (dose)(2), R-2 = 0.75; P < 0.05). Peak plasma concentrations off, following the 5- and 10-mg capsules were similar to each other and to those following the 0.5-mg injection (P > 0.05), but were lower than concentrations obtained following injection of 1.0-5.0 mg (P < 0.05). Across all treatments, both the maximum percentage decline in FSH and the interval to FSH nadir were related to the peak plasma concentrations of E-2 (maximum % decline in FSH = 11.17 + 1.561 (peak E-2)- 0.009 (peak E-2)(2), R-2 = 0.75; P < 0.01), (hours to FSH nadir = 10.678 + 1.486(hours to peak E-2) - 0.0782(hours to peak E-2)(2), R-2 = 0.22; P < 0.05). Concentrations of FSH increased as E-2 declined from its peak value, irrespective of maximum value achieved. It was concluded that the intramuscular administration of ODB in oil to ovariectomised heifers given a PRID results in higher plasma concentrations of E-2 and causes a greater reduction in FSH than administration topically by intravaginal gelatine capsule. E-2 transiently suppresses FSH in ovariectomised heifers. and the magnitude of the suppression is dose-dependent; however FSH concentrations begin to increase 1-2 days after ODB administration while concentrations of E-2 were declining but still high. (C) 2000 Elsevier Science B.V. All rights reserved. C1 TEAGASC, Agr & Food Dev Author, Athenry Res Ctr, Galway, Ireland. Univ Coll Dublin, Fac Med Vet, Dublin 2, Ireland. RP Diskin, MG (reprint author), TEAGASC, Agr & Food Dev Author, Athenry Res Ctr, Galway, Ireland. NR 35 TC 31 Z9 32 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4320 J9 ANIM REPROD SCI JI Anim. Reprod. Sci. PD APR 28 PY 2000 VL 59 IS 1-2 BP 1 EP 12 DI 10.1016/S0378-4320(99)00094-9 PG 12 WC Agriculture, Dairy & Animal Science; Reproductive Biology SC Agriculture; Reproductive Biology GA 312NE UT WOS:000086948700001 PM 10804271 ER PT J AU Gerasimov, MR Schiffer, WK Brodie, JD Lennon, IC Taylor, SJC Dewey, SL AF Gerasimov, MR Schiffer, WK Brodie, JD Lennon, IC Taylor, SJC Dewey, SL TI gamma-Aminobutyric acid mimetic drugs differentially inhibit the dopaminergic response to cocaine SO EUROPEAN JOURNAL OF PHARMACOLOGY LA English DT Article DE gamma-aminobutyric acid (GABA); dopamine; microdialysis; cocaine; gamma-vinyl GABA (vigabatrin); gamma-aminobutyric acid (GABA) reuptake inhibitor ID NUCLEUS-ACCUMBENS DOPAMINE; GABA UPTAKE INHIBITOR; EXTRACELLULAR DOPAMINE; VINYL-GABA; LOCOMOTOR-ACTIVITY; RATS; RELEASE; MODULATION; VIGABATRIN; TIAGABINE AB Dopaminergic activity in the mesocorticolimbic system is associated with reinforcing properties of psychostimulant drugs. We previously demonstrated that increased gamma-aminobutyric acid (GABA)-ergic activity produced by gamma-vinyl GABA [D,L-4-amino-hex-5-enoic acid (Vigabatrin(R))], an irreversible inhibitor of GABA-transaminase, attenuated cocaine, nicotine, heroin, alcohol, and methamphetamine-induced increases in extracellular nucleus accumbens dopamine as well as behaviors associated with three biochemical changes. In the present study, using in vivo microdialysis techniques, we compared three different strategies to increase GABAergic activity in order to modulate cocaine-induced increase in extracellular dopamine. Our data demonstrate that the anticonvulsant 1-(2-(((diphenylmethylene)amino)oxy)ethyl)-1,2,5,6-tetrahydro-3-pyridinecarboxylic acid hydrochloride (NNC-711), a GAB A uptake inhibitor, dose and time dependently diminished increases in extracellular dopamine following acute cocaine challenge. Furthermore, we demonstrated that cyclized analogue of vigabatrin, a competitive reversible GABA-transaminase inhibitor, is a more potent inhibitor of cocaine-induced dopamine increase than vigabatrin. Our data suggest that in addition to irreversible inhibition of GABA transaminase, inhibition of GABA uptake represent another potentially effective, indirect strategy for the treatment of cocaine abuse. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Gerasimov, MR (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NIMH NIH HHS [MH49165]; PHS HHS [R2955155] NR 41 TC 32 Z9 32 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0014-2999 J9 EUR J PHARMACOL JI Eur. J. Pharmacol. PD APR 28 PY 2000 VL 395 IS 2 BP 129 EP 135 DI 10.1016/S0014-2999(00)00267-3 PG 7 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 310DQ UT WOS:000086811600007 PM 10794818 ER PT J AU Lewis, LH Gallagher, K Wu, K Branagan, DJ Sellers, CH AF Lewis, LH Gallagher, K Wu, K Branagan, DJ Sellers, CH TI Evidence for elemental partitioning in gas-atomized Nd2Fe14B modified by alloying additions SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE magnetically ordered material; rapid solidification processing; chemical segregation; magnetic properties ID MAGNETIC-PROPERTIES; PERMANENT AB Measurements of the Curie and spin reorientation temperatures provide information about elemental partitioning as a function of effective quench rate in Nd2Fe14B-based powders modified by alloying additions, including Ti and C. The Curie and spin reorientation temperatures of inert gas-atomized (IGA) powders of various size fractions and annealing conditions were measured using differential thermal analysis (DTA) and SQUID AC magnetometry. The Curie temperatures of all size fractions of the Ti/C-containing powders are lower for both the as-quenched and annealed portions than those of the Ti/C-free powders. The spin reorientation temperatures of the Ti/C-modified material are found to be significantly lower than that expected for pure Nd2Fe14B. The data suggest that the alloying additions reside in the Nd2Fe14B lattice to varying degrees, dependent upon the quench rate experienced by the particle, and are expelled from the compound to the grain boundaries upon extended annealing. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Brookhaven Natl Lab, Dept Appl Sci, Div Mat & Chem Sci, Upton, NY 11973 USA. Lockheed Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Brookhaven Natl Lab, Dept Appl Sci, Div Mat & Chem Sci, Upton, NY 11973 USA. EM lhlewis@bnl.gov NR 21 TC 1 Z9 1 U1 1 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 EI 1873-4669 J9 J ALLOY COMPD JI J. Alloy. Compd. PD APR 28 PY 2000 VL 302 IS 1-2 BP 239 EP 247 DI 10.1016/S0925-8388(99)00823-3 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 302YJ UT WOS:000086393800041 ER PT J AU Sen, CK Khanna, S Roy, S Packer, L AF Sen, CK Khanna, S Roy, S Packer, L TI Molecular basis of vitamin E action - Tocotrienol potently inhibits glutamate-induced pp60(c-Src) kinase activation and death of HT4 neuronal cells SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID OSTEOCLASTIC BONE-RESORPTION; ALPHA-LIPOIC ACID; OXIDATIVE STRESS; C-SRC; TYROSINE KINASE; LIPID-PEROXIDATION; ENDOTHELIAL-CELLS; CYSTINE UPTAKE; ANTIOXIDANT; LINE AB HT4 hippocampal neuronal cells were studied to compare the efficacy of tocopherols and tocotrienol to protect against glutamate-induced death. Tocotrienols were more effective than alpha-tocopherol in preventing glutamate-induced death. Uptake of tocotrienols from the culture medium was more efficient compared with that of alpha-tocopherol. Vitamin E molecules have potent antioxidant properties. Results show that at low concentrations, tocotrienols may have protected cells by an antioxidant-independent mechanism. Examination of signal transduction pathways revealed that protein tyrosine phosphorylation processes played a central role in the execution of death. Activation of pp60(c-Src) kinase and phosphorylation of ERK were observed in response to glutamate treatment. Nanomolar amounts of cy-tocotrienol, but not alpha-tocopherol, blocked glutamate-induced death by suppressing glutamate-induced early activation of c-Src kinase. Overexpression of kinase-active c-Src sensitized cells to glutamate-induced death. Tocotrienol treatment prevented death of Src-overexpressing cells treated with glutamate. alpha-Tocotrienol did not influence activity of recombinant c-Src kinase suggesting that its mechanism of action may include regulation of SH domains. This study provides first evidence describing the molecular basis of tocotrienol action. At a concentration 4-10-fold lower than levels detected in plasma of supplemented humans, tocotrienol regulated unique signal transduction processes that were not sensitive to comparable concentrations of tocopherol. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. RP Sen, CK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,Bldg 90,Rm 3031, Berkeley, CA 94720 USA. RI Sen, Chandan/A-8762-2013; Khanna, Savita/E-3378-2011; Roy, sashwati/E-3990-2011 FU NIGMS NIH HHS [GM27345] NR 60 TC 206 Z9 212 U1 1 U2 5 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD APR 28 PY 2000 VL 275 IS 17 BP 13049 EP 13055 DI 10.1074/jbc.275.17.13049 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 309HK UT WOS:000086762300093 PM 10777609 ER PT J AU Quinones, I Cavazzini, A Guiochon, G AF Quinones, I Cavazzini, A Guiochon, G TI Adsorption equilibria and overloaded band profiles of basic drugs in a reversed-phase system SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE adsorption isotherms; band profiles; mathematical modeling; buspirone; doxepin; diltiazem ID PERFORMANCE LIQUID-CHROMATOGRAPHY; SILICA-GEL; PH; RETENTION; ISOTHERMS; MODEL AB Single-solute adsorption equilibrium isotherms of three basic drugs: buspirone, doxepin and diltiazem were determined by frontal analysis in a reversed-phase system composed of an octadecylsilica packing material and a buffered mobile phase containing acetonitrile. The adsorption data were fitted to the bi-langmuir model. Within the framework of this model, the adsorption of the drugs is assumed to occur on two distinct kinds of sites with different average adsorption energies. The data are consistent with the assumption that the low energy sites account for the hydrophobic interactions between the solutes and the chemically bonded alkyl chains and the high energy sites account for the ion-exchange interactions between the residual active silanols and the protonated bases. Multisolute, overloaded band profiles were also measured for the three binaries and for mixtures of the three drugs. Theoretical band profiles were calculated using the equilibrium dispersive model and the ideal adsorbed solution theory model which uses the parameters determined from the correlation of the single-solute adsorption data. Good agreement was found between the experimental and calculated overloaded band profiles. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Chem Engn, 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. RI Cavazzini, Alberto/B-7051-2015 OI Cavazzini, Alberto/0000-0002-2510-0871 NR 24 TC 26 Z9 26 U1 0 U2 5 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 APR 28 PY 2000 VL 877 IS 1-2 BP 1 EP 11 DI 10.1016/S0021-9673(00)00183-7 PG 11 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 312GW UT WOS:000086935800001 PM 10845785 ER PT J AU Khattabi, S Cherrak, DE Fischer, J Jandera, P Guiochon, G AF Khattabi, S Cherrak, DE Fischer, J Jandera, P Guiochon, G TI Study of the adsorption behavior of the enantiomers of 1-phenyl-1-propanol on a cellulose-based chiral stationary phase SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE enantiomer separation; adsorption isotherms; chiral stationary phases; LC; 1-phenyl-1-propanol ID CHROMATOGRAPHY AB Using single-step frontal analysis, we measured single-component and competitive adsorption isotherm data for the two enantiomers of I-phenyl-l-propanol (PP). These experimental data were fitted to several competitive bi-langmuir models (with 8, 6, 5 and 4 parameters) and to the competitive Langmuir model. The latter model accounted well for the behavior of both PP enantiomers on Chiracel OB (cellulose tribenzoate coated on silica gel). The parameters obtained were used in numerical calculations to predict the band profiles of the two single components and of their mixtures under overloaded conditions. The equilibrium-dispersive model provides satisfactory results, with minor differences between the calculated and the experimental profiles. These differences became negligible when a more complex kinetic model was used, with a concentration-dependent rate coefficient. (C) 2000 Elsevier Science BN. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Food Sci & Technol, Knoxville, TN 37901 USA. Oak Ridge Natl Lab, Dept Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Pardubice, Dept Analyt Chem, Pardubice, Czech Republic. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 14 TC 23 Z9 23 U1 2 U2 6 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 APR 28 PY 2000 VL 877 IS 1-2 BP 95 EP 107 DI 10.1016/S0021-9673(00)00133-3 PG 13 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 312GW UT WOS:000086935800008 PM 10845792 ER PT J AU Cherrak, DE Khattabi, S Guiochon, G AF Cherrak, DE Khattabi, S Guiochon, G TI Adsorption behavior and prediction of the band profiles of the enantiomers of 3-chloro-1-phenyl-1-propanol - Influence of the mass transfer kinetics SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE adsorption isotherms; mass transfer; enantiomer separation; chiral stationary phases; LC; band profiles; 3-chloro-1-phenyl-1-propanol ID PERFORMANCE LIQUID-CHROMATOGRAPHY; MOVING-BED CHROMATOGRAPHY; CHIRAL STATIONARY PHASES; 2 ENANTIOMERS; SEPARATION; CELLULOSE; RESOLUTION; DEPENDENCE; ISOTHERMS AB The single-component and competitive adsorption isotherms of the enantiomers of 3-chloro-1-phenyl-1-propanol were measured by frontal analysis. The stationary phase was a cellulose tribenzoate coated on silica, the mobile phase an n-hexane-ethyl acetate (95:5) solution. The adsorption data measured fitted well to the Langmuir isotherm model. The band profiles of single components and of their mixtures were calculated using the equilibrium-dispersive model. These profiles were found to match quite satisfactorily the experimental band profiles. However, the agreement between calculated and experimental band profiles was significantly improved when a more complex model taking into account the mass transfer kinetics was used. The mass transfer rate coefficients, k(f), for both single components were determined by using the transport-dispersive model of chromatography. The coefficients obtained were used to predict the band profiles of mixtures of the two enantiomers to good agreement. (C) 2000 Elsevier Science BN. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Food Sci & Technol, Knoxville, TN 37996 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 21 TC 24 Z9 24 U1 0 U2 6 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 APR 28 PY 2000 VL 877 IS 1-2 BP 109 EP 122 DI 10.1016/S0021-9673(00)00189-8 PG 14 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 312GW UT WOS:000086935800009 PM 10845793 ER PT J AU Gong, XY Yeung, ES AF Gong, XY Yeung, ES TI Genetic typing and HIV-1 diagnosis by using 96 capillary array electrophoresis and ultraviolet absorption detection SO JOURNAL OF CHROMATOGRAPHY B LA English DT Article; Proceedings Paper CT Symposium on Novel Technologies in Biomedical Analysis CY JUN 27-30, 1999 CL SANDEFJORD, NORWAY SP EU Commiss DE genetic typing ID LASER-INDUCED FLUORESCENCE; POLYMERASE CHAIN-REACTION; REPLACEABLE LINEAR POLYACRYLAMIDE; CROSS-LINKED POLYACRYLAMIDE; DNA RESTRICTION FRAGMENTS; GEL-ELECTROPHORESIS; STRANDED-DNA; HIGH-SPEED; CONFORMATION POLYMORPHISM; REACTION PRODUCTS AB Current high-throughput approaches to the analysis of PCR products are based primarily on electrophoretic separation and laser-excited fluorescence detection. We show that capillary array electrophoresis can be applied to HIV-1 diagnosis and D1S80 VNTR genetic typing based simply on UV absorption detection. The additive contribution of each base pair to the total absorption signal provides adequate detection sensitivity for analyzing most PCR products. Not only is the use of specialized and potentially toxic fluorescent labels eliminated, but also the complexity and cost of the instrumentation are greatly reduced. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Ames Lab, USDOE, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Yeung, ES (reprint author), Iowa State Univ, Ames Lab, USDOE, Ames, IA 50011 USA. NR 37 TC 17 Z9 18 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4347 J9 J CHROMATOGR B JI J. Chromatogr. B PD APR 28 PY 2000 VL 741 IS 1 BP 15 EP 21 DI 10.1016/S0378-4347(00)00165-1 PG 7 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 310HB UT WOS:000086819500003 PM 10839127 ER PT J AU Lu, G Zheng, C Donahoe, RJ Lyons, WB AF Lu, G Zheng, C Donahoe, RJ Lyons, WB TI Controlling processes in a CaCO3 precipitating stream in Huanglong Natural Scenic District, Sichuan, China SO JOURNAL OF HYDROLOGY LA English DT Article DE stream; aqueous chemistry; calcium carbonate; vaterite; travertine; precipitation ID CALCITE PRECIPITATION; KINETICS; ISOTOPE; DISSOLUTION; SYSTEMS; CO2 AB Huanglong Scenic District is well known for its unusual and diversified landforms such as travertine pools, travertine falls and travertine flows. These landforms, resulting from high-altitude surface cold-water CaCO3 precipitation, were chosen by UNESCO in 1994 as an entry in The World's Nature Heritage. Huanglong is a pristine region where there are limited human activities. Water analyses and thin section (glass slide) precipitation experiments were conducted to determine the aqueous processes controlling CaCO3 precipitation and travertine landform formation. Results from the travertine how indicate that the concentrations of HCO3-, Ca+2, and H+ decrease regularly along the how paths. Chemical equilibrium modeling results demonstrate the importance of CO2 out-gassing and CaCO3 precipitation processes. CO2 out-gassing and CaCO3 Precipitation increase with increasing flow velocities. In the pool area, varying hydrodynamics are the primary factors which determine the extent of processes such as advection and diffusion, and hence also control CaCO3 precipitation and CO2 out-gassing. When the pool water circulation is very slow, the pH of water flowing over the travertine dams increases significantly (approximately 0.15 pH units) downstream. When the circulation is relatively fast, the pH of stream water initially decreases followed by an increase of approximately 0.21 pH units as it flows past the travertine pool dams. In both cases, the pn rise is caused by sudden changes in the hydrodynamics of thr pools, despite the different initial flow conditions. Pool development is a consequence of spatial variations in pH which provide different conditions for CaCO3 precipitation inside the travertine dam, where less precipitation or even dissolution occurs, compared to conditions at the top and downstream side of the dams. Precipitation experiments demonstrate that the top and downstream side of travertine darns are the locations of the most active precipitation, particularly for pools having faster circulation. Precipitation experiments also reveal that vaterite, a rare polymorph of CaCO3, co-precipitates with calcite in milky opalescent water near the upstream input portion of the pool groups. Thin sections covered by algae at the bottom of pools have 40% less CaCO3 precipitation than those not covered by algae. SEM photographs of the surface of natural travertine deposits show that biofilms with diatom minimize CaCO3 precipitation and that diatom-adhered calcite surfaces show signs of etching, suggesting that calcite dissolution may be aided by diatoms, (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Alabama, Dept Geol Sci, Tuscaloosa, AL 35487 USA. Univ Calif Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. RP Lu, G (reprint author), Univ Alabama, Dept Geol Sci, Box 870338, Tuscaloosa, AL 35487 USA. RI Zheng, Chunmiao/I-5257-2014 OI Zheng, Chunmiao/0000-0001-5839-1305 NR 25 TC 39 Z9 46 U1 3 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD APR 28 PY 2000 VL 230 IS 1-2 BP 34 EP 54 DI 10.1016/S0022-1694(00)00171-2 PG 21 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 308VY UT WOS:000086734600003 ER PT J AU Williams, MD Oostrom, M AF Williams, MD Oostrom, M TI Oxygenation of anoxic water in a fluctuating water table system: an experimental and numerical study SO JOURNAL OF HYDROLOGY LA English DT Article DE anoxic water; dissolved oxygen; fluctuating water table; air entrapment; natural attenuation ID GOVERNING MULTIPHASE FLOW; NONAQUEOUS-PHASE LIQUID; TRAPPED GAS-PHASE; POROUS-MEDIA; LABORATORY EXPERIMENTS; DISSOLVED-OXYGEN; KINETIC-MODEL; TRANSPORT AB A side effect of in situ groundwater remediation techniques that operate by establishing reducing conditions within an aquifer is that anoxic water exits these zones, posing a potential risk to aquatic organisms inhabiting areas of groundwater discharge downgradient from the site. A number of processes have been identified that can attenuate an anoxic plume in an unconfined aquifer with a fluctuating water table. The hypothesis that water table fluctuations increase oxygen transfer from air to water, through enhanced exchange from entrapped air, is tested in an intermediate-scale, fluctuating water table experiment. A dual-energy gamma radiation system was used to measure water saturations while dissolved oxygen (DO) concentrations were measured with flow-through oxygen microelectrodes. A hysteretic multifluid simulator was used to test whether the experimentally obtained water and entrapped air saturations, as well as DO concentrations, could be predicted using the assumptions of two-phase flow and equilibrium partitioning between the gas and the aqueous phases. The experimental results show that zones with entrapped air, formed during the imbibition portions of the experiment, were instrumental in re-oxygenation of the water. The fluctuating water table system also caused significant amounts of dissolved oxygen to be transported deeper into the Row cell. The simulator was able to predict water and entrapped air saturations, as well as dissolved oxygen concentrations reasonably well. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Environm Technol Div, Richland, WA 99352 USA. RP Oostrom, M (reprint author), Pacific NW Natl Lab, Environm Technol Div, POB 999,MS K9-33, Richland, WA 99352 USA. NR 34 TC 51 Z9 52 U1 4 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD APR 28 PY 2000 VL 230 IS 1-2 BP 70 EP 85 DI 10.1016/S0022-1694(00)00172-4 PG 16 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 308VY UT WOS:000086734600005 ER PT J AU Boettger, JC Trickey, SB AF Boettger, JC Trickey, SB TI Inclusion of relativistic effects in Gaussian-basis density functional calculations for extended systems SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article DE relativistic effects; density functional calculations; extended systems ID GENERALIZED GRADIENT APPROXIMATION; DOUGLAS-KROLL TRANSFORMATION; STRUCTURAL PHASE-STABILITY; FULL CHARGE-DENSITY; VARIATIONAL TREATMENT; ELECTRONIC-STRUCTURE; ELASTIC-CONSTANTS; TRANSITION-METALS; ACTINIDE METALS; ATOMIC VOLUME AB Non-perturbative calculation of the scalar relativistic contributions to the density functional total energy and one-electron energies of extended systems until recently has been via exploitation of the features of cellular basis sets (the Koelling-Harmon scheme and cousins) to achieve the decoupling of large and small components. Cellular basis sets are relatively uncommon in quantum chemistry codes; Gaussian-type orbitals are the de facto standard. Among the various order-by-order decouplings used for molecular calculations in quantum chemistry, the Douglas-Kroll transformation has advantages which have brought it to prominence. Here we review the first extension of that procedure to an all-electron, linear combination of Gaussian-type-orbitals, fitting function (LCGTO-FF) methodology for DFT calculations on crystals and ordered films. To show the power and accuracy of the method, we summarize results for Au, Mo, Th, and Pu. In general, values from the Gaussian methodology and from cellular-basis, all-electron, scalar-relativistic density functional codes are essentially indistinguishable. In every case of a difference compared to previously published results, the prediction of the Gaussian methodology has been confirmed by an independent high-quality cellular-based calculation. These outcomes verify that, for the first time, a single, consistent, systematic, first-principles, all-electron, full-potential DFT technique is available for prediction of the properties of complex crystalline, slab, ordered polymer, and cluster/molecule systems that contain heavy elements, all devoid of potentially troublesome algorithmic inconsistencies. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Florida, Dept Phys, Quantum Theory Project, Gainesville, FL 32611 USA. Univ Florida, Dept Chem, Quantum Theory Project, Gainesville, FL 32611 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Trickey, SB (reprint author), Univ Florida, Dept Phys, Quantum Theory Project, Gainesville, FL 32611 USA. NR 67 TC 6 Z9 6 U1 0 U2 2 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 APR 28 PY 2000 VL 501 BP 285 EP 296 DI 10.1016/S0166-1280(99)00440-6 PG 12 WC Chemistry, Physical SC Chemistry GA 322ZY UT WOS:000087541100034 ER PT J AU Thrall, KD Poet, TS AF Thrall, KD Poet, TS TI Determination of biokinetic interactions in chemical mixtures using real-time breath analysis and physiologically based pharmacokinetic modeling SO JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A LA English DT Article ID CYTOCHROME-P450 ISOZYMES; METABOLIC INTERACTIONS; TRICHLOROACETIC-ACID; RAT-LIVER; TRICHLOROETHYLENE; TOLUENE; BENZENE; EXPOSURE; INVIVO; XYLENE AB Regulatory agencies are challenged to conduct risk assessments on chemical mixtures without full information on toxicological interactions that may occur at real-world, low-dose exposure levels. The present study was. undertaken to investigate the pharmacokinetic impact of low-dose coexposures to toluene and trichloroethylene in vivo in male F344 rats using a real-time breath analysis system coupled with physiologically based pharmacokinetic (PBPK) modeling. Rats were exposed to compounds alone or as a binary mixture, at low (5 to 25 mg/kg) or high (240 to 800 mg/kg) dose levels. Exhaled breath from the exposed animals was monitored for the parent compounds and a PBPK model was used to analyze the data. At low doses, exhaled breath kinetics from the binary mixture exposure compared with those obtained during single exposures, thus indicating that no metabolic interaction occurred with these low doses. In contract, at higher doses the binary PBPK model simulating independent metabolism was found to underpredict the exhaled breath concentration, suggesting an inhibition of metabolism. Therefore the binary mixture PBPK model was used to compare the measured exhaled breath levels from high- and low-dose exposures with the predicted levels under various metabolic interaction simulations (competitive, noncompetitive, or uncompetitive inhibition). Of these simulations, the optimized competitive metabolic interaction description yielded a K-i value closest to the K-m of the inhibitor solvent, indicating that competitive inhibition is the most plausible type of metabolic interaction between these two solvents. C1 Battelle Mem Inst, Pacific NW Div, Mol Biosci Dept, Chem Dosimetry Grp, Richland, WA 99352 USA. RP Thrall, KD (reprint author), Battelle Mem Inst, Pacific NW Div, Mol Biosci Dept, Chem Dosimetry Grp, POB 999,Mail Stop P7-59, Richland, WA 99352 USA. NR 24 TC 15 Z9 15 U1 1 U2 6 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 1528-7394 J9 J TOXICOL ENV HEAL A JI J. TOXICOL. ENV. HEALTH PT A PD APR 28 PY 2000 VL 59 IS 8 BP 653 EP 670 DI 10.1080/009841000156646 PG 18 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 308XX UT WOS:000086739100005 PM 10839498 ER PT J AU Wunderlich, B Androsch, R Pyda, M Kwon, YK AF Wunderlich, B Androsch, R Pyda, M Kwon, YK TI Heat capacity by multi-frequencies sawtooth modulation SO THERMOCHIMICA ACTA LA English DT Article DE heat capacity; temperature-modulated differential scanning calorimetry (TMDSC); Fourier transformation; higher harmonics; sawtooth modulation ID DIFFERENTIAL SCANNING CALORIMETRY; TEMPERATURE; DSC AB In this paper a simple method is proposed to carry out temperature-modulated calorimetry with multiple frequencies. The method is based on modulation with a complex sawtooth. The harmonics of the Fourier series of the measured heat-how rate and temperature are used to extract data pertaining to the frequencies of the 1st, 3rd, 5th, 7th and 9th harmonic. The complex sawtooth produces similar modulation amplitudes of the temperature of the first four harmonics. In temperature-modulated differential scanning calorimetry with a period of less than about 150 s, corrections by extrapolation to zero frequency are commonly needed. With the proposed method, these extrapolations can be done in a single experiment. Difficulties of baseline subtraction and other possible instrumentation and software problems are discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 21 TC 31 Z9 31 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD APR 28 PY 2000 VL 348 IS 1-2 BP 181 EP 190 DI 10.1016/S0040-6031(99)00455-4 PG 10 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 306BT UT WOS:000086576800022 ER PT J AU von Salzen, K Leighton, HG Ariya, PA Barrie, LA Gong, SL Blanchet, JP Spacek, L Lohmann, U Kleinman, LI AF von Salzen, K Leighton, HG Ariya, PA Barrie, LA Gong, SL Blanchet, JP Spacek, L Lohmann, U Kleinman, LI TI Sensitivity of sulphate aerosol size distributions and CCN concentrations over North America to SOx emissions and H2O2 concentrations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; INORGANIC MULTICOMPONENT AEROSOLS; PROGNOSTIC PHYSICOCHEMICAL MODEL; TROPOSPHERIC SULFUR CYCLE; CHEMICAL-TRANSPORT MODEL; LARGE-SCALE ENVIRONMENT; CUMULUS CLOUD ENSEMBLE; REGIONAL CLIMATE MODEL; UNITED-STATES; SULFATE DISTRIBUTION AB To assess the influence of aerosols on climate, the Northern Aerosol Regional Climate Model (NARCM) is currently being developed. NARCM includes size-segregated aerosols as prognostic and interactive constituents. In this paper, the model is being applied to sulphate aerosol over North America during time periods in July and December 1994. The results give evidence for considerable regional and seasonal variations in sulphate aerosol size distributions over North America. Comparisons of the results with different observations yield a reasonably good agreement in terms of meteorological and physicochemical parameters. Some of the differences in sulphate concentrations and wet deposition rates can be attributed to differences in cloud amounts and precipitation between model results and observations. Indirect tests of the simulated aerosol mass mean diameters are also encouraging. Additional simulations for hypothetical decreases in anthropogenic sulphur emissions and increases in hydrogen peroxide (H2O2) background concentrations are performed for the same time periods to study the responses of concentration, size distribution, and wet deposition of sulphate aerosol to these changes. Also, responses of cloud condensation nuclei (CCN) number concentrations are investigated. The simulation results show that sulphate aerosol concentrations respond almost linearly in both time periods to decreases in sulphur emissions but that CCN number concentrations respond nonlinearly due to decreases in sulphate mass mean diameters. Especially for the December period, increases in hydrogen peroxide background concentrations lead to increases in CCN number concentrations at critical diameters larger than about 0.07 mu m. These results lead to the hypothesis that increased in-cloud oxidation in convective clouds due to future increases in oxidant concentrations may produce larger CCN which eventually can be easily activated in subsequently forming stratiform clouds. C1 McGill Univ, Dept Atmospher & Ocean Sci, Montreal, PQ H3A 2K6, Canada. Meteorol Serv Canada, Toronto, ON M3H 5T4, Canada. Univ Quebec, Dept Earth Sci, Montreal, PQ H3C 3P8, Canada. Dalhousie Univ, Dept Phys, Halifax, NS B3H 3J5, Canada. Brookhaven Natl Lab, Environm Chem Div, Upton, NY 11973 USA. RP von Salzen, K (reprint author), Univ Victoria, Ctr Climate Modelling & Anal, STN CSC, POB 1700, Victoria, BC V8W 2Y2, Canada. EM knut.vonsalzen@ec.gc.ca; henry@zephyr.meteo.mcgill.ca; ariya@omc.lan.mcgill.ca; leonard.barrie@pnl.gov; sunling.gong@ec.gc.ca; blanchet.jean-pierre@uqam.ca; spacek@atlas.sca.uqam.ca; ulrike@fizz.phys.dal.ca; kleinman@bnl.gov RI Ariya, Parisa/G-2810-2015; Lohmann, Ulrike/B-6153-2009 OI Lohmann, Ulrike/0000-0001-8885-3785 NR 78 TC 35 Z9 35 U1 0 U2 1 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 APR 27 PY 2000 VL 105 IS D8 BP 9741 EP 9765 DI 10.1029/2000JD900027 PG 25 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ND UT WOS:000086658600001 ER PT J AU Disselkamp, RS Carpenter, MA Cowin, JP Berkowitz, CM Chapman, EG Zaveri, RA Laulainen, NS AF Disselkamp, RS Carpenter, MA Cowin, JP Berkowitz, CM Chapman, EG Zaveri, RA Laulainen, NS TI Ozone loss in soot aerosols SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID REACTION-KINETICS; HEXANE SOOT; CARBON; TROPOSPHERE AB The fractal-like structure of atmospheric soot (e.g., elemental carbon) provides a large surface area available for heterogeneous chemistry in the upper troposphere and lower stratosphere [Blake and Kato, 1995]. One potentially important reaction is ozone decomposition on soot. Although extensively studied in the laboratory, a wide range of reaction probabilities have been observed (gamma similar to 10(-3) to gamma similar to 10(-7)) which have been attributed to differences in reactivity between fresh (i.e., nonoxidized) versus aged (i.e., oxidized) soot [Schurath and Naumann, 1998]. The importance in understanding soot-ozone chemistry is particularly important in light of recent nighttime field measurements [Berkowitz et al., 2000] made over Portland, Oregon. The data revealed episodes of an anticorrelation between ozone mixing ratio and aerosol surface area density. During these episodes a single scattering albedo in the range 0.8-0.9 was measured, indicating an increased absorptive component of the aerosol, perhaps due to elemental carbon. In addition, an increase in the concentration of aerosols contained in the small size range of the fine mode (<0.1-0.15 mu m) was observed, suggestive of new aerosol formation. In this article we attempt to explain these field observations. One explanation of the field observations is ozone loss occurring on atmospheric soot aerosol. Here we present laboratory results obtained using a static aerosol reactor that indicate that direct ozone loss on soot aerosol is unlikely under ambient conditions in the troposphere. An alternative and more likely explanation of the field data is based on ozone-mediated organic aerosol production. This could occur by either nighttime nitrate radical oxidation or direct ozone oxidation of hydrocarbons as suggested previously [Starn et al., 1998; Griffin ed al., 1999; Kamens et al., 1999; Yu et al., 1999; De Gouw and Lovejoy, 1998]. C1 Pacific NW Lab, Atmospher Sci Tech Grp, Richland, WA 99352 USA. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Disselkamp, RS (reprint author), Pacific NW Lab, Atmospher Sci Tech Grp, 902 Battelle Blvd, Richland, WA 99352 USA. EM robert.disselkamp@pnl.gov; michael.carpenter@pnl.gov; cowin@pnl.gov; carl.berkowitz@pnl.gov; elaine.chapman@pnl.gov.jp; rahul.zaveri@pnl.gov; nels.laulainen@pnl.gov RI Chapman, Elaine/K-8756-2012; OI Zaveri, Rahul/0000-0001-9874-8807 NR 29 TC 36 Z9 37 U1 1 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 27 PY 2000 VL 105 IS D8 BP 9767 EP 9771 DI 10.1029/1999JD901189 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ND UT WOS:000086658600002 ER PT J AU Whiteman, CD Zhong, S Bian, X Fast, JD Doran, JC AF Whiteman, CD Zhong, S Bian, X Fast, JD Doran, JC TI Boundary layer evolution and regional-scale diurnal circulations over the Mexico Basin and Mexican plateau SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID 4-DIMENSIONAL DATA ASSIMILATION; AIR-POLLUTION; MOUNTAINOUS TERRAIN; CANYONLAND BASIN; ENERGY-BALANCE; LOS-ANGELES; CITY; MODEL; HEAT; FLOWS AB Data collected in a measurement campaign in February and March 1997 showed that the Mexico Basin (also called the Valley of Mexico), located atop the Mexican plateau, fails to develop the strong nocturnal inversions usually associated with basins and does not exhibit diurnally reversing valley wind systems. Data analyses, two- and three-dimensional numerical simulations with the Regional Atmospheric Modeling System (RAMS), and a Lagrangian particle dispersion model are used to interpret these observations and to examine the effects of topography and regional diurnal circulations on boundary layer evolution over the Mexico Basin and its surroundings during fair weather periods in the winter dry season. We show that the boundary layer evolution in and above the basin is driven primarily by regional diurnal circulations that develop between the air above the Mexican Plateau and the generally cooler surrounding coastal areas. A convective boundary layer (CBL) grows explosively over the plateau in the late morning to reach elevations of 2250 m agl (4500 m msl) by noon, and a strong baroclinic zone forms on the edges of the plateau separating the warm CBL air from its cooler surroundings. In early afternoon the rates of heating and CBL growth are slowed as cool air leaks onto the plateau and into the basin through passes and over low-lying plateau edges. The flow onto the plateau is retarded, however, by the strongly rising branch of a plain-plateau circulation at the plateau edges, especially where mountains or steep slopes are present. An unusually rapid and deep cooling of the air above the plateau begins in late afternoon and early evening when the surface energy budget reverses, the CBL decays, and air accelerates onto the plateau through the baroclinic zone. Flow convergence near the basin floor and the associated rising motions over the basin and plateau produce cooling in 3 hours that is equivalent to half the daytime heating. While the air that converges onto the plateau comes from elevations at and above the plateau, it is air that was modified earlier in the day by a cool, moist coastal inflow carried up the plateau slopes by the plain-plateau circulation. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Whiteman, CD (reprint author), Pacific NW Natl Lab, POB 999,MSIN K9-30, Richland, WA 99352 USA. EM dave.whiteman@pnl.gov; shiyuan.zhong@pnl.gov; randy.x.bian@pnl.gov; jerome.fast@pnl.gov; christopher.doran@pnl.gov NR 47 TC 60 Z9 60 U1 1 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD APR 27 PY 2000 VL 105 IS D8 BP 10081 EP 10102 DI 10.1029/2000JD900039 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 307ND UT WOS:000086658600022 ER PT J AU Segal, D Nitzan, A Davis, WB Wasielewski, MR Ratner, MA AF Segal, D Nitzan, A Davis, WB Wasielewski, MR Ratner, MA TI Electron transfer rates in bridged molecular systems 2. A steady-state analysis of coherent tunneling and thermal transitions SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID REDUCED DENSITY-MATRICES; QUANTUM TIME EVOLUTION; DISTANCE DEPENDENCE; ENERGY-TRANSFER; TRANSFER KINETICS; PENTAAMMINERUTHENIUM COMPLEXES; ALKANETHIOL MONOLAYERS; SUPRAMOLECULAR SYSTEMS; TENSOR PROPAGATOR; DUPLEX DNA AB The effect of dephasing and relaxation on electron transfer in bridged molecular systems is investigated using a simple molecular model. The interaction between the molecular system and the thermal environment is described on the level of the Redfield theory, modified when needed for the description of steady-state situations. Noting that transient as well as steady-state measurements are possible in such system, we discuss the relationship between the rates obtained from these different types of experiments and, in particular, the conditions under which these rates are the same. Also, a formal relation between the steady-state rate for electron transfer across a molecular bridge and the conductance of this bridge when placed between two metal contacts is established. The effect of dephasing and relaxation on the electron transfer is investigated, and new observations are made with regard to the transition from the superexchange to the thermal (hopping through bridge) regime of the transfer process. In particular, the rate is temperature-independent in the superexchange regime, and its dependence on the bridge length (N) is exponential, exp(-beta N). The rate behaves like (alpha(1) + alpha(2)N)(-1) exp(-Delta E/k(B)T) beyond a crossover value of N, where Delta E is the energy gap between the donor/acceptor and the bridge levels, and where alpha(1) and alpha(2) are characteristic times for activation onto the bridge and diffusion in the bridge, respectively. We find that, in typical cases, alpha(1) >> alpha(2), and therefore, a region of very weak N dependence is expected before the Ohmic behavior, N-1, is established for large enough N. In addition, a relatively weak exponential dependence, exp(-alpha N), is expected for long bridges if competing processes capture electrons away from the bridge sites. Finally, we consider ways to distinguish experimentally between the thermal and the tunneling routes. C1 Tel Aviv Univ, Sackler Fac Med, Sch Chem, IL-69978 Tel Aviv, Israel. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Tel Aviv Univ, Sackler Fac Med, Sch Chem, IL-69978 Tel Aviv, Israel. RI Abraham, Nitzan/A-9963-2008 NR 90 TC 240 Z9 242 U1 1 U2 37 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 APR 27 PY 2000 VL 104 IS 16 BP 3817 EP 3829 DI 10.1021/jp993260f PG 13 WC Chemistry, Physical SC Chemistry GA 329GY UT WOS:000087900200010 ER PT J AU Kopidakis, N Schiff, EA Park, NG van de Lagemaat, J Frank, AJ AF Kopidakis, N Schiff, EA Park, NG van de Lagemaat, J Frank, AJ TI Ambipolar diffusion of photocarriers in electrolyte-filled, nanoporous TiO2 SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SOLAR-CELLS; DYE; TRANSPORT; PHOTOCURRENT; SPECTROSCOPY; PHOTOVOLTAGE; EFFICIENCY; SILICON; FILMS; MODEL AB We report transient photocurrent measurements on solar cell structures based on dye-sensitized, porous TiO2 films filled with a liquid electrolyte. The measurements are interpreted as ambipolar diffusion; under most measurement conditions, the ambipolar diffusion coefficient is dominated by electrons diffusing in the TiO2 matrix. We report a strong dependence of the ambipolar diffusion coefficient upon the photoexcitation density, as has been proposed previously. The coefficients vary from 10(-8) cm(2) s(-1) at low density to 10(-4) cm(2) s(-1) for densities of 10(18) cm(-3) At a specified photoexcitation density, ambipolar diffusion coefficients measured using weak laser pulses and optical bias are about 10 times larger than coefficients measured using large-intensity laser pulses. We describe trapping models for these effects based on an exponential distribution (T-0 = 650 K) of electron trap levels in TiO2. We infer an electron recombination cross section less than 2 x 10(-27) cm(2): this value is nearly 10 orders of magnitude smaller than typical values in compact semiconductors and indicates the extraordinarily effective separation of electrons in the TiO2 matrix from electrolyte ions only nanometers distant. C1 Syracuse Univ, Dept Phys, Syracuse, NY 13244 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Schiff, EA (reprint author), Syracuse Univ, Dept Phys, Syracuse, NY 13244 USA. RI van de Lagemaat, Jao/J-9431-2012; Park, Nam-Gyu/F-2477-2014; Kopidakis, Nikos/N-4777-2015 NR 37 TC 279 Z9 281 U1 3 U2 52 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 27 PY 2000 VL 104 IS 16 BP 3930 EP 3936 DI 10.1021/jp9936603 PG 7 WC Chemistry, Physical SC Chemistry GA 329GY UT WOS:000087900200025 ER PT J AU Family, F Hentschel, HGE Braiman, Y AF Family, F Hentschel, HGE Braiman, Y TI Friction at the nanoscale SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID STICK-SLIP MOTION; FRENKEL-KONTOROVA MODEL; DRY FRICTION; LUBRICATED SURFACES; SLIDING FRICTION; TOMLINSON MODEL; DYNAMICS; FLUCTUATIONS; OSCILLATORS; ARRAYS AB Dissipation mechanisms at the nanoscale are influenced by finite size effects that may significantly affect the frictional response of sliding objects. In particular, locking of temporal and spatial dynamics may introduce several distinct modes of motion leading to friction selection. Here, we discuss such nonlinear mechanisms leading to stick-slip dynamics at the atomic scale. C1 Emory Univ, Dept Phys, Atlanta, GA 30322 USA. Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Family, F (reprint author), Emory Univ, Dept Phys, Atlanta, GA 30322 USA. NR 36 TC 15 Z9 15 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 27 PY 2000 VL 104 IS 16 BP 3984 EP 3987 DI 10.1021/jp994260i PG 4 WC Chemistry, Physical SC Chemistry GA 329GY UT WOS:000087900200033 ER PT J AU Dohrmann, CR AF Dohrmann, CR TI Dynamics of a tire-wheel - Suspension assembly - Reply SO JOURNAL OF SOUND AND VIBRATION LA English DT Letter C1 Sandia Natl Labs, Struct Dynam Dept, Albuquerque, NM 87185 USA. RP Dohrmann, CR (reprint author), Sandia Natl Labs, Struct Dynam Dept, Mail Stop 0847, Albuquerque, NM 87185 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD APR 27 PY 2000 VL 232 IS 2 BP 474 EP 476 DI 10.1006/jsvi.1999.2741 PG 3 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 312WC UT WOS:000086966100010 ER PT J AU Cederstrom, B Cahn, RN Danielsson, M Lundqvist, M Nygren, DR AF Cederstrom, B Cahn, RN Danielsson, M Lundqvist, M Nygren, DR TI Focusing hard X-rays with old LPs SO NATURE LA English DT Article ID REFRACTIVE LENS C1 Royal Inst Technol, Dept Phys, SE-10405 Stockholm, Sweden. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. RP Cederstrom, B (reprint author), Royal Inst Technol, Dept Phys, SE-10405 Stockholm, Sweden. NR 5 TC 61 Z9 66 U1 1 U2 10 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 27 PY 2000 VL 404 IS 6781 BP 951 EP 951 DI 10.1038/35010190 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 309HG UT WOS:000086762000041 ER PT J AU de Bernardis, P Ade, PAR Bock, JJ Bond, JR Borrill, J Boscaleri, A Coble, K Crill, BP De Gasperis, G Farese, PC Ferreira, PG Ganga, K Giacometti, M Hivon, E Hristov, VV Iacoangeli, A Jaffe, AH Lange, AE Martinis, L Masi, S Mason, PV Mauskopf, PD Melchiorri, A Miglio, L Montroy, T Netterfield, CB Pascale, E Piacentini, F Pogosyan, D Prunet, S Rao, S Romeo, G Ruhl, JE Scaramuzzi, F Sforna, D Vittorio, N AF de Bernardis, P Ade, PAR Bock, JJ Bond, JR Borrill, J Boscaleri, A Coble, K Crill, BP De Gasperis, G Farese, PC Ferreira, PG Ganga, K Giacometti, M Hivon, E Hristov, VV Iacoangeli, A Jaffe, AH Lange, AE Martinis, L Masi, S Mason, PV Mauskopf, PD Melchiorri, A Miglio, L Montroy, T Netterfield, CB Pascale, E Piacentini, F Pogosyan, D Prunet, S Rao, S Romeo, G Ruhl, JE Scaramuzzi, F Sforna, D Vittorio, N TI A flat Universe from high-resolution maps of the cosmic microwave background radiation SO NATURE LA English DT Article ID ANISOTROPY; SUPERNOVAE; EMISSION AB The blackbody radiation left over from the Big Bang has been transformed by the expansion of the Universe into the nearly isotropic 2.73 K cosmic microwave background. Tiny inhomogeneities in the early Universe left their imprint on the microwave background in the form of small anisotropies in its temperature. These anisotropies contain information about basic cosmological parameters, particularly the total energy density and curvature of the Universe. Here we report the first images of resolved structure in the microwave background anisotropies over a significant part of the sky. Maps at four frequencies clearly distinguish the microwave background from foreground emission. We compute the angular power spectrum of the microwave background, and rnd a peak at Legendre multipole I-peak = (197 +/- 6), with an amplitude Delta T-200 = (69 +/- 8) mu K. This is consistent with that expected for cold dark matter models in a flat (euclidean) Universe, as favoured by standard inflationary models. C1 Univ Rome La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Univ London Queen Mary & Westfield Coll, Dept Phys, London E1 4NS, England. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Toronto, CITA, Toronto, ON M5S 3H8, Canada. LBNL, NERSC, Berkeley, CA 94720 USA. CNR, IROE, I-50127 Florence, Italy. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. CALTECH, Pasadena, CA 91125 USA. Univ Roma Tor Vergata, Dipartimento Fis, I-00133 Rome, Italy. Univ Oxford, Oxford OX1 3RH, England. Coll France, PCC, F-75231 Paris 05, France. Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. ENEA, Ctr Ric Frascati, I-00044 Frascati, Italy. Cardiff Univ, Dept Phys & Astron, Cardiff CF2 3YB, S Glam, Wales. Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA. Univ Toronto, Dept Phys & Astron, Toronto, ON M5S 3H8, Canada. Ist Nazl Geofis, I-00143 Rome, Italy. RP de Bernardis, P (reprint author), Univ Rome La Sapienza, Dipartimento Fis, P A Moro 2, I-00185 Rome, Italy. RI Jaffe, Andrew/D-3526-2009; de Gasperis, Giancarlo/C-8534-2012; Piacentini, Francesco/E-7234-2010; OI de Gasperis, Giancarlo/0000-0003-2899-2171; Piacentini, Francesco/0000-0002-5444-9327; Masi, Silvia/0000-0001-5105-1439; de Bernardis, Paolo/0000-0001-6547-6446; ROMEO, Giovanni/0000-0002-5535-7803; Melchiorri, Alessandro/0000-0001-5326-6003; Hivon, Eric/0000-0003-1880-2733 NR 47 TC 1814 Z9 1817 U1 4 U2 125 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 27 PY 2000 VL 404 IS 6781 BP 955 EP 959 DI 10.1038/35010035 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 309HG UT WOS:000086762000045 ER PT J AU Bauer, CW Ligeti, Z Luke, M AF Bauer, CW Ligeti, Z Luke, M TI A model independent determination of vertical bar V-ub vertical bar SO PHYSICS LETTERS B LA English DT Article ID SEMILEPTONIC B-DECAY; LEPTON SPECTRUM; NONPERTURBATIVE CORRECTIONS; INVARIANT MASS; QCD; DISTRIBUTIONS; BEAUTY; MESONS AB It is shown that measuring the lepton invariant mass spectrum in inclusive semileptonic (B) over bar --> X(u)l<(nu)over bar> decay yields a model independent determination of \V-ub\. Unlike the lepton energy and hadronic invariant mass spectra, nonperturbative effects are only important in the resonance region, and play a parametrically suppressed role when d Gamma/dq(2) is integrated over q(2) > (m(B) - m(D))(2), which is required to eliminate the charm background. Perturbative and nonperturbative corrections are presented to order alpha(s)(2)beta(0) and Lambda(QCD)(2)/m(b)(2), and the Lambda(QCD)(3)/m(b)(3) corrections are used to estimate the uncertainty in our results. The utility of the (B) over bar --> X(s)l(+)l(-) decay rate above the psi(2S) resonance is discussed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. Fermilab, Theory Grp, Batavia, IL 60510 USA. RP Bauer, CW (reprint author), Univ Toronto, Dept Phys, 60 St George St, Toronto, ON M5S 1A7, Canada. NR 38 TC 62 Z9 62 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 27 PY 2000 VL 479 IS 4 BP 395 EP 401 DI 10.1016/S0370-2693(00)00318-X PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 311GY UT WOS:000086877400006 ER PT J AU Wan, WL Chan, TF Smith, B AF Wan, WL Chan, TF Smith, B TI An energy-minimizing interpolation for robust multigrid methods SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE multigrid; interpolation; energy minimization; nonsmooth coefficient; elliptic differential equations ID DEPENDENT TRANSFER OPERATORS; ELLIPTIC PROBLEMS; DIFFUSION-PROBLEMS; ITERATIVE METHODS; GRID METHOD; DECOMPOSITION; CONVERGENCE; COEFFICIENTS; ALGORITHMS; EQUATIONS AB We propose a robust interpolation for multigrid based on the concepts of energy minimization and approximation. It can handle PDE coefficients of various types on structured or unstructured grids under one framework. The formulation is general; it can be applied to any dimension. We demonstrate numerically the effectiveness of the multigrid method in two dimensions by applying it to a discontinuous coefficient problem, an oscillatory coefficient problem, and an anisotropic problem. Empirically, the convergence rate is independent of the coefficients of the underlying PDE, in addition to being independent of the mesh size. The proposed method is primarily designed for second-order elliptic PDEs, with possible extensions to other classes of problems such as integral equations. C1 Stanford Univ, SCCM Program, Stanford, CA 94305 USA. Univ Calif Los Angeles, Dept Math, Los Angeles, CA 90095 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Wan, WL (reprint author), Stanford Univ, SCCM Program, Gates Bldg 2B, Stanford, CA 94305 USA. RI Chan, Tony/A-4166-2013 NR 44 TC 51 Z9 52 U1 1 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PD APR 27 PY 2000 VL 21 IS 4 BP 1632 EP 1649 PG 18 WC Mathematics, Applied SC Mathematics GA 312GN UT WOS:000086935000024 ER PT J AU Li, W Meitzner, GD Borry, RW Iglesia, E AF Li, W Meitzner, GD Borry, RW Iglesia, E TI Raman and X-ray absorption studies of Mo species in Mo/H-ZSM5 catalysts for non-oxidative CH4 reactions SO JOURNAL OF CATALYSIS LA English DT Article ID MOLYBDENUM CARBIDE CATALYSTS; K-EDGE; METHANE; CONVERSION; SPECTROSCOPY; BENZENE; AROMATIZATION; SPECTRA; ZEOLITE; DEHYDROGENATION AB The structure of MoOx and MoCy species in Mo/H-ZSM5 after exchange and during CH4 reactions was probed by in situ Raman and X-ray absorption spectroscopy. Raman spectra of physical mixtures of H-ZSM5 and MoO3 powders initially showed strong Raman bands characteristic of bulk MoO3. The intensity of Raman bands for Mo-O-Mo decreased relative to those for Mo=O bonds during treatment in air at 773 K, suggesting that MoO3 spreads as (MoO3), oligomers on external zeolite surfaces. The Raman bands for MoO3 crystallites became much weaker after treatment in air at 973 K; this occurred concurrently with H2O evolution, indicating that dispersed MoOx species exchanged with acidic OH groups in the zeolite. Weak bands appeared at 970 and 1045 cm(-1) they were assigned to stretching modes in exchanged MoOx species, The X-ray near-edge spectrum of MoO3/H-ZSM5 mixtures gradually evolves to one characteristic of tetrahedral Mo6+ centers in bulk MgMo2O7 as H2O forms during treatment at 773-973 K, confirming that exchange occurs in this temperature range. Each Mo6+ replaces one H+ at all Mo contents (Mo/Al= 0.11-0.37). The radial structure function derived from the absorption fine structure also evolves from that for bulk MoO3, to that expected of dispersed MoO3 without long-range periodicity, to one described using multiple scattering simulations as a (Mo2O7)(2-) dimer resembling MgMo2O7 with two of the (C) atoms located in the zeolite framework. This structure is consistent with the exchange stoichiometry from H2O desorption and with the removal of 2.5 O/Mo during reduction-carburization. The required number of Al pairs in the samples to accommodate the dimer structures is within the range predicted by Monte Carlo calculation of Al statistical distribution. The absorption edge and near-edge features in exchanged MoOx/-ZSM5 evolve during CH4 reactions at 973 K to resemble bulk Mo2C without long-range periodicity, with the concurrent evolution of CO, CO2, and H2O and an increase in the rate of hydrocarbon formation. Multiple scattering analysis of a MoCx cluster bonded to an O atom leads to a radial structure function in excellent agreement with experiment. (C) 2000 Academic Press. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Edge Analyt, Middleton, WI 53562 USA. RP Iglesia, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Iglesia, Enrique/D-9551-2017 OI Iglesia, Enrique/0000-0003-4109-1001 NR 43 TC 103 Z9 106 U1 6 U2 54 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9517 J9 J CATAL JI J. Catal. PD APR 25 PY 2000 VL 191 IS 2 BP 373 EP 383 DI 10.1006/jcat.1999.2795 PG 11 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 317QN UT WOS:000087238600013 ER PT J AU Sault, AG Martino, A Kawola, JS Boespflug, E AF Sault, AG Martino, A Kawola, JS Boespflug, E TI Novel sol-gel-based Pt nanocluster catalysts for propane dehydrogenation SO JOURNAL OF CATALYSIS LA English DT Article DE sol-gel; aerogel; xerogel; platinum; dehydrogenation; propane ID PT/SIO2 CATALYSTS; ISOBUTANE DEHYDROGENATION; RU CATALYSTS; SILICA; HYDROGENOLYSIS; STABILIZATION; PRECURSOR; SUPPORT; AEROGEL; PD AB We report the propane dehydrogenation behavior of catalysts prepared using two novel synthesis strategies that combine inverse micelle Pt nanocluster technology with silica and alumina sol-gel processing. Unlike some other sol-gel catalyst preparations, Pt particles in these catalysts are not encapsulated in the support structure and the entire Pt particle surface is accessible for reaction. Turnover frequencies for these catalysts are comparable to those obtained over Pt catalysts prepared by traditional techniques such as impregnation, yet the resistance to deactivation by carbon poisoning is much greater in our catalysts. The deactivation behavior is more typical of traditionally prepared PtSn catalysts than of pure Pt catalysts. (C) 2000 Academic Press. C1 Sandia Natl Labs, Catalyt & Porous Mat Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Dept Chem Technol, Albuquerque, NM 87185 USA. RP Sault, AG (reprint author), Sandia Natl Labs, Catalyt & Porous Mat Dept, POB 5800, Albuquerque, NM 87185 USA. NR 33 TC 25 Z9 26 U1 4 U2 34 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9517 J9 J CATAL JI J. Catal. PD APR 25 PY 2000 VL 191 IS 2 BP 474 EP 479 DI 10.1006/jcat.1999.2782 PG 6 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 317QN UT WOS:000087238600023 ER PT J AU Schoenemann, PT Budinger, TF Sarich, VM Wang, WSY AF Schoenemann, PT Budinger, TF Sarich, VM Wang, WSY TI Brain size does not predict general cognitive ability within families SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID INTELLIGENCE; MRI; PRIMATES AB Hominid brain size increased dramatically in the face of apparently severe associated evolutionary costs. This suggests that increasing brain size must have provided some sort of counterbalancing adaptive benefit. Several recent studies using magnetic resonance imaging (MRI) have indicated that a substantial correlation (mean r = approximate to 0.4) exists between brain size and general cognitive performance, consistent with the hypothesis that the payoff for increasing brain size was greater general cognitive ability. However, these studies confound between-family environmental influences with direct genetic/biological influences. To address this problem, within-family (WF) sibling differences for several neuroanatomical measures were correlated to WF scores on a diverse battery of cognitive tests in a sample of 36 sibling pairs. WF correlations between neuroanatomy and general cognitive ability were essentially zero, although moderate correlations were found between prefrontal volumes and the Stroop test (known to involve prefrontal cortex). These findings suggest that nongenetic influences play a role in brain volume/cognitive ability associations. Actual direct genetic/biological associations may be quite small, and yet still may be strong enough to account for hominid brain evolution. C1 Univ Penn, Univ Museum 325, Dept Anthropol, Philadelphia, PA 19104 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Anthropol, Berkeley, CA 94720 USA. City Univ Hong Kong, Dept Elect Engn, Kowloon, Hong Kong, Peoples R China. Univ Calif Berkeley, Dept Linguist, Berkeley, CA 94720 USA. RP Schoenemann, PT (reprint author), Univ Penn, Univ Museum 325, Dept Anthropol, 33rd & Spruce St, Philadelphia, PA 19104 USA. NR 53 TC 51 Z9 51 U1 0 U2 7 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 APR 25 PY 2000 VL 97 IS 9 BP 4932 EP 4937 DI 10.1073/pnas.97.9.4932 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 308GW UT WOS:000086703000096 PM 10781101 ER PT J AU Balcioglu, A Ahrenkiel, RK Friedman, DJ AF Balcioglu, A Ahrenkiel, RK Friedman, DJ TI Evidence of an oxygen recombination center in p(+)-n GaInNAs solar cells SO APPLIED PHYSICS LETTERS LA English DT Article ID SPECTROSCOPY AB We have studied deep-level impurities in p(+)-n GaInNAs solar cells using deep-level transient spectroscopy (DLTS). These films were grown by atmospheric- and low-pressure metalorganic vapor-phase epitaxy. The base layer is doped with silicon, and the emitter layer is zinc doped. Two types of samples have been studied: samples were grown with and without the addition of oxygen impurity. Two electron traps were found in all samples. These are designated as: E1, at E-C-0.23-E-C-0.27 eV, E2 at E-C-0.45 eV, and E2* at 0.77 eV. With the addition of oxygen impurity, DLTS showed additional traps designated as E3 (electron) at E-C-0.59 eV and H3 (hole) at E-V+0.59 eV. Using secondary ion mass spectroscopy, the oxygen concentration was found to be about 2-3x10(19) and 1x10(17) cm(-3) in two sets of samples. However, only samples containing oxygen contained the two near-midgap levels (E3 and H3). We present evidence that these levels are associated with the oxygen defect. As we change the dc bias voltage, the E3 trap disappears in unison with the appearance of the H3 trap. Furthermore, E3 and H3 trap levels have comparable capture cross sections. This oxygen-related trap is an effective recombination center. The measured Shockley-Hall-Read lifetime for this center is about 0.6 mu s. (C) 2000 American Institute of Physics. [S0003-6951(00)04617-9]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Balcioglu, A (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 15 TC 26 Z9 26 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 24 PY 2000 VL 76 IS 17 BP 2397 EP 2399 DI 10.1063/1.126383 PG 3 WC Physics, Applied SC Physics GA 305KJ UT WOS:000086538700025 ER PT J AU Skierbiszewski, C Perlin, P Wisniewski, P Knap, W Suski, T Walukiewicz, W Shan, W Yu, KM Ager, JW Haller, EE Geisz, JF Olson, JM AF Skierbiszewski, C Perlin, P Wisniewski, P Knap, W Suski, T Walukiewicz, W Shan, W Yu, KM Ager, JW Haller, EE Geisz, JF Olson, JM TI Large, nitrogen-induced increase of the electron effective mass in InyGa1-yNxAs1-x SO APPLIED PHYSICS LETTERS LA English DT Article ID ALLOYS; GAAS1-XNX AB A dramatic increase of the conduction band electron mass in a nitrogen-containing III-V alloy is reported. The mass is found to be strongly dependent on the nitrogen content and the electron concentration with a value as large as 0.4m(0) in In0.08Ga0.92As0.967N0.033 with 6x10(19) cm(-3) free electrons. This mass is more than five times larger than the electron effective mass in GaAs and comparable to typical heavy hole masses in III-V compounds. The results provide a critical test and fully confirm the predictions of the recently proposed band anticrossing model of the electronic structure of the III-N-V alloys. (C) 2000 American Institute of Physics. [S0003-6951(00)04817-8]. C1 Polish Acad Sci, UNIPRESS, PL-01142 Warsaw, Poland. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Skierbiszewski, C (reprint author), Polish Acad Sci, UNIPRESS, Ul Sokolowska 29, PL-01142 Warsaw, Poland. RI Yu, Kin Man/J-1399-2012; KNAP, WOJCIECH/H-8043-2016; OI Yu, Kin Man/0000-0003-1350-9642; KNAP, WOJCIECH/0000-0003-4537-8712; Ager, Joel/0000-0001-9334-9751 NR 18 TC 215 Z9 216 U1 2 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 24 PY 2000 VL 76 IS 17 BP 2409 EP 2411 DI 10.1063/1.126360 PG 3 WC Physics, Applied SC Physics GA 305KJ UT WOS:000086538700029 ER PT J AU Park, C Norton, DP Verebelyi, DT Christen, DK Budai, JD Lee, DF Goyal, A AF Park, C Norton, DP Verebelyi, DT Christen, DK Budai, JD Lee, DF Goyal, A TI Nucleation of epitaxial yttria-stabilized zirconia on biaxially textured (001) Ni for deposited conductors SO APPLIED PHYSICS LETTERS LA English DT Article ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; MECHANICAL-PROPERTIES; THIN-FILMS; SURFACES; GROWTH; NICKEL; OXIDE; YBA2CU3O7; ZRO2 AB The nucleation of (001)-oriented yttria-stabilized zirconia (YSZ) directly on the (001) Ni surface is realized via nucleation on an oxygen-terminated nickel surface using pulsed-laser deposition. Under conditions where the nickel surface is either oxygen free or substantially covered with NiO, a mixed orientation of YSZ occurs. The epitaxial YSZ layer grown on a biaxially textured Ni(001) surface was used as a single buffer layer for a high temperature superconducting coated conductor architecture, yielding superconducting YBa2Cu3O7 films with high critical current densities, J(c). This architecture eliminates the necessity for a multilayer buffer architecture, since high J(c) superconducting films are achieved with no intermediate buffer layer between the (001) YSZ and the biaxially textured metal. (C) 2000 American Institute of Physics. [S0003-6951(00)04516-2]. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Norton, DP (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Yoon, Sejin/F-7637-2013; Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 18 TC 28 Z9 28 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 24 PY 2000 VL 76 IS 17 BP 2427 EP 2429 DI 10.1063/1.126365 PG 3 WC Physics, Applied SC Physics GA 305KJ UT WOS:000086538700035 ER PT J AU Battle, CC Kim, S Gopalan, V Barkocy, K Gupta, MC Jia, QX Mitchell, TE AF Battle, CC Kim, S Gopalan, V Barkocy, K Gupta, MC Jia, QX Mitchell, TE TI Ferroelectric domain reversal in congruent LiTaO3 crystals at elevated temperatures SO APPLIED PHYSICS LETTERS LA English DT Article ID SINGLE-CRYSTALS; LINBO3; FIELD AB We report a four-times decrease in the electric fields for 180 degrees domain reversal in congruent LiTaO3 crystals with an increase in temperature from 22 to 250 degrees C. This is accompanied by a substantial broadening of the field range over which domain reversal takes place, by an order of magnitude. The large internal fields of similar to 5.5 kV/mm at room temperature, as measured by the asymmetry in polarization hysteresis loop, disappears at higher temperatures. With increasing temperature, the domain switching changes from lateral growth dominated to nucleation dominated kinetics. (C) 2000 American Institute of Physics. [S0003-6951(00)01417-0]. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. Old Dominion Univ, Coll Engn & Technol, Appl Res Ctr, Newport News, VA 23606 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Battle, CC (reprint author), Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. RI Jia, Q. X./C-5194-2008 NR 21 TC 16 Z9 17 U1 0 U2 8 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 24 PY 2000 VL 76 IS 17 BP 2436 EP 2438 DI 10.1063/1.126368 PG 3 WC Physics, Applied SC Physics GA 305KJ UT WOS:000086538700038 ER PT J AU Song, YD Robinson, M AF Song, YD Robinson, M TI Special issue on wind turbines: dynamics, control and monitoring SO JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS LA English DT Editorial Material C1 N Carolina Agr & Technol State Univ, Dept Elect Engn, Greensboro, NC 27411 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Song, YD (reprint author), N Carolina Agr & Technol State Univ, Dept Elect Engn, Greensboro, NC 27411 USA. RI Song, Yong-Duan/A-2730-2015 NR 0 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6105 J9 J WIND ENG IND AEROD JI J. Wind Eng. Ind. Aerodyn. PD APR 24 PY 2000 VL 85 IS 3 BP 209 EP 210 PG 2 WC Engineering, Civil; Mechanics SC Engineering; Mechanics GA 308FX UT WOS:000086700800001 ER PT J AU Muljadi, E Pierce, K Migliore, P AF Muljadi, E Pierce, K Migliore, P TI Soft-stall control for variable-speed stall-regulated wind turbines SO JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS LA English DT Article DE renewable energy; wind turbine; stall control; variable speed; fatigue load mitigation; wound rotor induction generator AB A variable-speed, fixed-pitch wind turbine control strategy was investigated to evaluate the feasibility of constraining rotor speed and power output without the benefit of active aerodynamic control devices. A strategy was postulated to control rotational speed by specifying the demanded generator torque. By controlling rotor speed in relation to wind speed, the aerodynamic power extracted by the blades from the wind was manipulated. Specifically, the blades were caused to stall in high winds. In low and moderate winds, the demanded generator torque and the resulting rotor speed were controlled and the wind turbine operated near maximum efficiency. Turbine models were developed and simulations of operation in turbulent winds were conducted. Results indicated that rotor speed and power output were well regulated. Preliminary investigations of system dynamics (E. Muljadi, K. Pierce, P. Migliore, A conservative control strategy for variable-speed stall-regulated wind turbines, AIAA-2000-31 A Collection of the 2000 ASME Wind Energy Symposium Technical Papers presented at the 38th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV, January 2000). Showed that, compared to fixed-speed operation, variable-speed operation caused cyclic loading amplitude to be reduced for the turbine blades and low-speed shaft and slightly increased for the tower loads. This result suggests that implementation of the proposed control strategy will have a favorable impact on the turbine's fatigue life. The concept was implemented on a 275 kW wind turbine test bed (K. Pierce, P. Migliore, Maximizing the energy capture of fixed-pitch variable-speed wind turbines, AIAA-2000-0032 ASME Wind Energy Symposium Technical Papers presented at the 38th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV, January 2000). Test data show that the wind turbine performance matches the predicted simulation results. The control concept was shown to operate the wind turbine near maximum efficiency in low-to-moderate wind speeds, while stalling the rotor in the high winds to regulate speed and output power. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Natl Wind Technol Ctr, Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Muljadi, E (reprint author), Natl Wind Technol Ctr, Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 7 TC 29 Z9 33 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6105 J9 J WIND ENG IND AEROD JI J. Wind Eng. Ind. Aerodyn. PD APR 24 PY 2000 VL 85 IS 3 BP 277 EP 291 DI 10.1016/S0167-6105(99)00130-0 PG 15 WC Engineering, Civil; Mechanics SC Engineering; Mechanics GA 308FX UT WOS:000086700800005 ER PT J AU Streich, S Briggs, G Blacic, J Schilte, P Peterson, C AF Streich, S Briggs, G Blacic, J Schilte, P Peterson, C TI Drilling technology for Mars research useful for oil, gas industries SO OIL & GAS JOURNAL LA English DT Article C1 Halliburton Energy Serv Inc, Duncan, OK 73533 USA. NASA, Moffett Field, CA USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Shell Oil Co, Rijswijk, Netherlands. NADET Inst, Boxford, MA USA. RP Streich, S (reprint author), Halliburton Energy Serv Inc, Duncan, OK 73533 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU PENNWELL PUBL CO ENERGY GROUP PI TULSA PA 1421 S SHERIDAN RD PO BOX 1260, TULSA, OK 74101 USA SN 0030-1388 J9 OIL GAS J JI Oil Gas J. PD APR 24 PY 2000 VL 98 IS 17 BP 46 EP + PG 5 WC Energy & Fuels; Engineering, Petroleum SC Energy & Fuels; Engineering GA 311KQ UT WOS:000086883700018 ER PT J AU Rasmussen, KO Cretegny, T Kevrekidis, PG Gronbech-Jensen, N AF Rasmussen, KO Cretegny, T Kevrekidis, PG Gronbech-Jensen, N TI Statistical mechanics of a discrete nonlinear system SO PHYSICAL REVIEW LETTERS LA English DT Article ID LOCALIZATION; BREATHERS; ENERGY; MODEL AB Statistical mechanics of the discrete nonlinear Schrodinger equation is studied by means of analytical and numerical techniques. The lower bound of the Hamiltonian permits the construction of standard Gibbsian equilibrium measures for positive temperatures. Beyond the line of T = infinity, we identify a phase transition through a discontinuity in the partition function. The phase transition is demonstrated to manifest itself in the creation of breatherlike localized excitations. Interrelation between the statistical mechanics and the nonlinear dynamics of the system is explored numerically in both regimes. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. RP Cretegny, T (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Rasmussen, Kim/B-5464-2009 OI Rasmussen, Kim/0000-0002-4029-4723 NR 12 TC 71 Z9 71 U1 3 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 APR 24 PY 2000 VL 84 IS 17 BP 3740 EP 3743 DI 10.1103/PhysRevLett.84.3740 PG 4 WC Physics, Multidisciplinary SC Physics GA 307CM UT WOS:000086635900002 ER PT J AU Adler, S Atiya, MS Chiang, IH Diwan, MV Frank, JS Haggerty, JS Jain, V Kettell, SH Kycia, TF Li, KK Littenberg, LS Ng, C Strand, RC Witzig, C Kazumori, M Komatsubara, TK Kuriki, M Muramatsu, N Otomo, A Sugimoto, S Inagaki, T Kabe, S Kobayashi, M Kuno, Y Sato, T Shinkawa, T Yoshimura, Y Kishi, Y Nakano, T Sasaki, T Ardebili, M Bazarko, AO Convery, MR Ito, MM Marlow, DR McPherson, RA Meyers, PD Shoemaker, FC Smith, AJS Stone, JR Aoki, M Bergbusch, PC Blackmore, EW Bryman, DA Konaka, A Macdonald, JA Mildenberger, J Numao, T Padley, P Poutissou, JM Poutissou, R Redlinger, G Kitching, P Soluk, R AF Adler, S Atiya, MS Chiang, IH Diwan, MV Frank, JS Haggerty, JS Jain, V Kettell, SH Kycia, TF Li, KK Littenberg, LS Ng, C Strand, RC Witzig, C Kazumori, M Komatsubara, TK Kuriki, M Muramatsu, N Otomo, A Sugimoto, S Inagaki, T Kabe, S Kobayashi, M Kuno, Y Sato, T Shinkawa, T Yoshimura, Y Kishi, Y Nakano, T Sasaki, T Ardebili, M Bazarko, AO Convery, MR Ito, MM Marlow, DR McPherson, RA Meyers, PD Shoemaker, FC Smith, AJS Stone, JR Aoki, M Bergbusch, PC Blackmore, EW Bryman, DA Konaka, A Macdonald, JA Mildenberger, J Numao, T Padley, P Poutissou, JM Poutissou, R Redlinger, G Kitching, P Soluk, R CA E787 Collaboration TI Further search for the decay K+->pi(+)nu(nu)over-bar SO PHYSICAL REVIEW LETTERS LA English DT Article ID ENDCAP PHOTON DETECTOR; 500 MHZ; K->PI-NU(NU)OVER-BAR AB A search for additional evidence for the rare kaon decay K+ --> pi(+)nu<(nu)over bar> has been made with a new data set comparable in sensitivity to the previous exposure that produced a single event. No new events were found in the pion momentum region examined, 211 < P < 229 MeV/c. Including a reanalysis of the original data set, the backgrounds were estimated to contribute 0.08 +/- 0.02 events. Based on one observed event, the new branching ratio is B(K+ --> pi(+)nu<(nu)over bar>) = 1.5(-1.2)(+3.4) x 10(-10). C1 Brookhaven Natl Lab, Upton, NY 11973 USA. KEK, High Energy Accelerator Res Org, Tanashi Branch, Tanashi, Tokyo 1888501, Japan. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 3050801, Japan. Osaka Univ, RCNP, Ibaraki, Osaka 5670047, Japan. Princeton Univ, Joseph Henry Labs, Princeton, NJ 08544 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ Alberta, Ctr Subatom Res, Edmonton, AB T6G 2N5, Canada. SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. RP Adler, S (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Marlow, Daniel/C-9132-2014 NR 12 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 APR 24 PY 2000 VL 84 IS 17 BP 3768 EP 3770 DI 10.1103/PhysRevLett.84.3768 PG 3 WC Physics, Multidisciplinary SC Physics GA 307CM UT WOS:000086635900009 ER PT J AU Son, DT AF Son, DT TI Hydrodynamics of nuclear matter in the chiral limit SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHASE-TRANSITION; QCD AB Using the Poisson bracket method, we construct the hydrodynamics of nuclear matter in the chiral limit. which describes the dynamics of all low-energy degrees of freedom, including the fluid-dynamical and pionic ones. The hydrodynamic equations contain, beside five Euler equations of relativistic fluid dynamics, N-f(2) - 1 second order equations describing propagating pions and N-f(2) - 1 first order equations describing the advection of the vector isospin charges. We present hydrodynamic arguments showing that the pion velocity vanishes at the second order phase transition at N-f = 2. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. RP Son, DT (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. NR 18 TC 21 Z9 21 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 APR 24 PY 2000 VL 84 IS 17 BP 3771 EP 3774 DI 10.1103/PhysRevLett.84.3771 PG 4 WC Physics, Multidisciplinary SC Physics GA 307CM UT WOS:000086635900010 ER PT J AU Poolman, HR Boersma, DJ Harvey, M Higinbotham, DW Passchier, I Six, E Alarcon, R van Amersfoort, PW Bauer, TS Rookhuizen, HB van den Brand, JFJ van Buuren, LD Bulten, HJ Ent, R Ferro-Luzzi, M Geurts, DG Heimberg, P de Jager, CW Klimin, P Koop, I Kroes, F van der Laan, J Luijckx, G Lysenko, A Militsyn, B Nesterenko, I Noomen, J Norum, BE van den Putte, MJJ Shatunov, Y Steijger, JJM Szczerba, D de Vries, H AF Poolman, HR Boersma, DJ Harvey, M Higinbotham, DW Passchier, I Six, E Alarcon, R van Amersfoort, PW Bauer, TS Rookhuizen, HB van den Brand, JFJ van Buuren, LD Bulten, HJ Ent, R Ferro-Luzzi, M Geurts, DG Heimberg, P de Jager, CW Klimin, P Koop, I Kroes, F van der Laan, J Luijckx, G Lysenko, A Militsyn, B Nesterenko, I Noomen, J Norum, BE van den Putte, MJJ Shatunov, Y Steijger, JJM Szczerba, D de Vries, H TI Experiments with longitudinally polarized electrons in a storage ring using a Siberian snake SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUASI-ELASTIC SCATTERING; NEUTRON SPIN STRUCTURE; STRUCTURE-FUNCTION G(1)(N); PRECISION-MEASUREMENT; INTERNAL TARGET; HE-3; ENERGY AB We report on first measurements with polarized electrons stored in a medium-energy ring and with a polarized internal target. Polarized electrons were injected at 442 MeV (653 MeV), and a partial (full) Siberian snake was employed to preserve the polarization. Longitudinal polarization at the interaction point and polarization lifetime of the stored electrons were determined with laser backscattering. Spin observables were measured for electrodisintegration of polarized He-3, with simultaneous detection of scattered electrons, protons, neutrons, deuterons, and He-3 nuclei, over a large phase space. C1 Vrije Univ Amsterdam, Dept Phys & Astron, NL-1081 HV Amsterdam, Netherlands. NIKHEF H, NL-1009 DB Amsterdam, Netherlands. Univ Utrecht, Dept Phys, NL-3508 TA Utrecht, Netherlands. TJNAF, Newport News, VA 23606 USA. Hampton Univ, Dept Phys, Hampton, VA 23668 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. Arizona State Univ, Dept Phys, Tempe, AZ 85287 USA. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. ETH Zurich, Inst Teilchenphys, CH-8093 Zurich, Switzerland. RP Poolman, HR (reprint author), Vrije Univ Amsterdam, Dept Phys & Astron, De Boelelaan 1085, NL-1081 HV Amsterdam, Netherlands. RI Higinbotham, Douglas/J-9394-2014 OI Higinbotham, Douglas/0000-0003-2758-6526 NR 30 TC 4 Z9 4 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 APR 24 PY 2000 VL 84 IS 17 BP 3855 EP 3858 DI 10.1103/PhysRevLett.84.3855 PG 4 WC Physics, Multidisciplinary SC Physics GA 307CM UT WOS:000086635900031 ER PT J AU Hsu, SC Fiksel, G Carter, TA Ji, H Kulsrud, RM Yamada, M AF Hsu, SC Fiksel, G Carter, TA Ji, H Kulsrud, RM Yamada, M TI Local measurement of nonclassical ion heating during magnetic reconnection SO PHYSICAL REVIEW LETTERS LA English DT Article ID LABORATORY PLASMA AB Local ion temperature and flows are measured directly in the well-characterized reconnection layer of a laboratory plasma. The measurements indicate strongly that ions are heated due to reconnection and that more than half of the reconnected field energy is converted to ion thermal energy. Neither classical viscous damping of the observed sub-Alfvenic ion flows nor classical energy exchange with electrons is sufficient to account for the ion heating, suggesting the importance of nonclassical dissipation mechanisms in the reconnection layer. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Hsu, SC (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Carter, Troy/E-7090-2010; Yamada, Masaaki/D-7824-2015; OI Carter, Troy/0000-0002-5741-0495; Yamada, Masaaki/0000-0003-4996-1649; Hsu, Scott/0000-0002-6737-4934 NR 20 TC 39 Z9 43 U1 0 U2 1 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 APR 24 PY 2000 VL 84 IS 17 BP 3859 EP 3862 DI 10.1103/PhysRevLett.84.3859 PG 4 WC Physics, Multidisciplinary SC Physics GA 307CM UT WOS:000086635900032 ER EF