FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Hull, JR AF Hull, JR TI Superconducting bearings SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Review ID HIGH-T-C; HIGH-TEMPERATURE SUPERCONDUCTORS; SINGLE-DOMAIN YBA2CU3OX; ELECTROMAGLEV ACTIVE-MAGLEV; YBACUO BULK SUPERCONDUCTORS; ALTERNATING MAGNETIC-FIELD; ENERGY-STORAGE SYSTEMS; LEVITATION FORCE; II SUPERCONDUCTORS; PERMANENT-MAGNETS AB The physics and technology of superconducting bearings is reviewed. Particular attention is given to the use of high-temperature superconductors (HTSs) in rotating bearings. The basic phenomenology of levitational forces is presented, followed by a brief discussion of the theoretical models that can be used for conceptual understanding and calculations. The merits of various HTS bearing designs are presented, and the behaviour of HTS bearings in typical situations is discussed. The article concludes with a brief survey of various proposed applications for HTS bearings. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Hull, JR (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 161 TC 300 Z9 320 U1 10 U2 65 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 FEB PY 2000 VL 13 IS 2 BP R1 EP R15 DI 10.1088/0953-2048/13/2/201 PG 15 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 287VB UT WOS:000085526200001 ER PT J AU Berman, GP Doolen, GD Tsifrinovich, VI AF Berman, GP Doolen, GD Tsifrinovich, VI TI Solid-state quantum computation - a new direction for nanotechnology SO SUPERLATTICES AND MICROSTRUCTURES LA English DT Article; Proceedings Paper CT 3rd NASA Workshop on Device Modeling CY AUG 26-27, 1999 CL NASA AMES RES CTR, MOFFETT FIELD, CALIFORNIA SP NASA HO NASA AMES RES CTR DE quantum computers; qubit; nanotechnology ID MAGNETIC-RESONANCE; ERROR-CORRECTION; COMPUTER; SPECTROSCOPY AB We review current proposals for six types of solid-state quantum computers. We discuss the general requirements for solid-state quantum computers and describe proposals which employ superconducting junctions, electron orbitals in quantum: dots, electron spin resonance, nuclear spins of impurity atoms, and nuclear spins in a crystal lattice. We also describe our proposed nuclear spin quantum computer based on magnetic resonance force microscopy. Finally we describe our numerical method for modeling quantum:transformations with a large number (up to 1000) of qubits. (C) 2000 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, CNLS, Los Alamos, NM 87545 USA. Polytech Univ, Dept Phys, Metrotech Ctr 6, Brooklyn, NY 11201 USA. RP Berman, GP (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. NR 46 TC 38 Z9 40 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 FEB-MAR PY 2000 VL 27 IS 2-3 BP 89 EP 104 DI 10.1006/spmi.1999.0801 PG 16 WC Physics, Condensed Matter SC Physics GA 294CB UT WOS:000085891400005 ER PT J AU Zasada, I Van Hove, MA AF Zasada, I Van Hove, MA TI Refinement of the Pt(111)+c(4 x 2)-2CO structure using automated tensor LEED SO SURFACE REVIEW AND LETTERS LA English DT Article ID DIPOLE-FORBIDDEN MODES; INFRARED-SPECTROSCOPY; VIBRATIONAL FREQUENCY; BONDING MECHANISM; CO ADSORPTION; SURFACE; RELIABILITY; DYNAMICS AB The structure of Pt(111)+c(4 x 2)-2CO has been refined using the powerful capabilities of automated tensor LEED, in particular to determine hitherto-unexplored adsorbate-induced relaxations in the substrate. The refinement considerably improves the fit to experiment obtained in a previous structural analysis performed with low-energy electron diffraction (LEED). This study confirms that CO occupies both top and bridge sites. It finds a buckling of the outermost Pt layer, such that the Pt atoms bonded to CO molecules are raised out of the surface by 0.06 +/- 0.04 Angstrom relative to the Pt atoms which do not bond to CO. The raised atoms have a spacing of 2.28 +/- 0.04 Angstrom to the next Pt layer, expanded from the bulk spacing of 2.2655 Angstrom, while the depressed Pt atoms have a reduced spacing of 2.22 +/- 0.04 Angstrom to the next Pt layer. The second Pt layer itself shows minor buckling of 0.03 +/- 0.04 A. No lateral relaxations in the substrate are detected within 0.1 A. The CO molecules are perpendicular to the surface, with bond lengths of 1.12 +/- 0.04 Angstrom and 1.19 +/- 0.04 Angstrom in top and bridge sites, respectively. The C-Pd spacings, measured between bonding atoms, are 1.92 +/- 0.04 Angstrom and 1.40 +/- 0.04 Angstrom in top and bridge sites, respectively. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Lodz, Dept Solid State Phys, PL-90131 Lodz, Poland. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Van Hove, MA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Van Hove, Michel/A-9862-2008 OI Van Hove, Michel/0000-0002-8898-6921 NR 33 TC 15 Z9 15 U1 1 U2 2 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-625X J9 SURF REV LETT JI Surf. Rev. Lett. PD FEB-APR PY 2000 VL 7 IS 1-2 BP 15 EP 19 DI 10.1016/S0218-625X(00)00004-X PG 5 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 338JJ UT WOS:000088415700003 ER PT J AU Hucek, S Zemek, J Jablonski, A Tilinin, IS AF Hucek, S Zemek, J Jablonski, A Tilinin, IS TI Emission depth distribution function of Al 2s photoelectrons in Al2O3 SO SURFACE REVIEW AND LETTERS LA English DT Article ID MEAN FREE PATHS; ESCAPE PROBABILITY; SIGNAL ELECTRONS; SURFACE-ANALYSIS; SPECTROSCOPY; SCATTERING; SOLIDS; ATTENUATION; OXIDE; XPS AB The escape probability of Al 2s photoelectrons leaving an aluminum oxide sample (Al2O3) has been studied as a function of depth of origin. It has been found that the escape probability (the so-called emission depth distribution function - DDF) depends strongly on the photoelectron emission direction with respect to that of the incident X-ray beam. In particular, in the emission direction close to that of photon propagation, the DDF differs substantially from the simple Beer-Lambert law and exhibits a nonmonotonic behavior with a maximum in the near-surface region at a depth of about 10 Angstrom. Experimental results are in good agreement with theoretical predictions based on Monte Carlo simulations of the electron transport and with analytical solution of the linearized Boltzmann kinetic equation with appropriate boundary conditions. Both theoretical approaches take into account multiple elastic scattering of photoelectrons on their way out of the sample. It is shown that the commonly used straight line approximation (SLA), which neglects elastic scattering effects, fails to describe adequately experimental data at emission directions close to minima of the differential photoelectric cross section. C1 Acad Sci Czech Republ, Inst Parasitol, CR-37005 Ceske Budejovice, Czech Republic. Acad Sci Czech Republ, Inst Phys, Prague 16253 6, Czech Republic. Polish Acad Sci, Inst Phys Chem, PL-01224 Warsaw, Poland. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Hucek, S (reprint author), Acad Sci Czech Republ, Inst Parasitol, Branisovska 31, CR-37005 Ceske Budejovice, Czech Republic. RI Zemek, Josef/G-6203-2014 NR 20 TC 6 Z9 6 U1 1 U2 6 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-625X J9 SURF REV LETT JI Surf. Rev. Lett. PD FEB-APR PY 2000 VL 7 IS 1-2 BP 109 EP 114 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 338JJ UT WOS:000088415700013 ER PT J AU Kelber, JA Niu, CY Shepherd, K Jennison, DR Bogicevic, A AF Kelber, JA Niu, CY Shepherd, K Jennison, DR Bogicevic, A TI Copper wetting of alpha-Al2O3(0001): theory and experiment SO SURFACE SCIENCE LA English DT Article DE ab initio quantum chemical methods and calculations; aluminum oxide; chemisorption; copper; sputter deposition; wetting; X-ray photoelectron spectroscopy ID MOLECULAR-DYNAMICS; FILM GROWTH; METAL-OXIDE; AL2O3; CU; SURFACES; XPS; CLUSTERS; SPECTROSCOPY; ADSORPTION AB X-ray photoelectron spectroscopy (XPS) studies have been carried out on sputter deposited copper on a substantially hydroxylated alpha-Al2O3(0001) (sapphire) surface under ultra-high vacuum (UHV) conditions. XPS-derived Cu uptake curves show a sharp change in slope at a coverage of 0.35 ML (on a Cu/O atomic basis), indicative of initial layer-by-layer growth. Cu(LMM) lineshape data indicate that, prior to the first break in the curve, Cu is oxidized to Cu(I). At higher coverages, metallic Cu(O) is observed. These data agree with first principles theoretical calculations, indicating that the presence of adhydroxyl groups greatly enhances the binding of Cu to bulk sapphire surfaces, stabilizing Cu(I) adatoms over two-dimensional metallic islands. In the absence of hydroxylation, calculations indicate significantly weaker Cu binding to the bulk sapphire substrate and non-wetting. Calculations also predict that at Cu coverages above 1/3 ML, Cu--Cu interactions predominate, leading to Cu(O) formation. These results are in excellent agreement with experiment. The ability of surface hydroxyl groups to enhance binding to alumina substrates suggests a reason for contradictory experimental results reported in the literature for Cu wetting of alumina. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ N Texas, Dept Chem, Denton, TX 76203 USA. Sandia Natl Labs, Surface & Interface Sci Dept, Albuquerque, NM 87185 USA. RP Univ N Texas, Dept Chem, Denton, TX 76203 USA. EM kelber@bob.unt.edu NR 50 TC 72 Z9 72 U1 1 U2 26 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 EI 1879-2758 J9 SURF SCI JI Surf. Sci. PD FEB 1 PY 2000 VL 446 IS 1-2 BP 76 EP 88 DI 10.1016/S0039-6028(99)01089-4 PG 13 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 282DF UT WOS:000085200800015 ER PT J AU Mckay, MD Beckman, RJ Conover, WJ AF Mckay, MD Beckman, RJ Conover, WJ TI A comparison of three methods for selecting values of input variables in the analysis of output from a computer code SO TECHNOMETRICS LA English DT Article DE Latin hypercube sampling; sampling techniques; simulation techniques; variance reduction AB Two types of sampling plans are examined as alternatives to simple random sampling in Monte Carlo studies. These plans are shown to be improvements over simple random sampling with respect to variance for a class of estimators which includes the sample mean and the empirical distribution function. C1 Los Alamos Sci Lab, Los Alamos, NM 87545 USA. Texas Tech Univ, Dept Math, Lubbock, TX 79409 USA. RP Mckay, MD (reprint author), Los Alamos Sci Lab, POB 1663, Los Alamos, NM 87545 USA. NR 17 TC 254 Z9 275 U1 20 U2 116 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD FEB PY 2000 VL 42 IS 1 BP 55 EP 61 DI 10.2307/1271432 PG 7 WC Statistics & Probability SC Mathematics GA 274XR UT WOS:000084790800009 ER PT J AU Lewis, CJ Verges, J Marzo, M AF Lewis, CJ Verges, J Marzo, M TI High mountains in a zone of extended crust: Insights into the Neogene-Quaternary topographic development of northeastern Iberia SO TECTONICS LA English DT Article ID WESTERN MEDITERRANEAN BASIN; VALENCIA TROUGH; VERTICAL MOVEMENTS; GEOLOGICAL EVOLUTION; VELOCITY STRUCTURE; FLEXURAL ISOSTASY; OROGENIC BELT; SIERRA-NEVADA; RIFT; LITHOSPHERE AB Topographic analysis combined with geological and geophysical observations indicate that much of the present configuration of the northeastern Iberian Peninsula derives from Neogene-Quaternary opening of the western Mediterranean basins following the Pyrenean orogeny. Mountainous topography up to 2000 m lines the Mediterranean coastal margin of Cataluna (Spain) despite a crustal thickness of 22 km at the coast. Geometric analysis of topographic profiles indicates a strong link between topography and extensional tectonics. Trends in maximum, mean and minimum elevations show marked regional increases in a SW-NE direction along the axis of the Ebro basin towards the active Amer-Brugent normal fault. From patterns of local relief, characteristics of the fluvial drainage network, location of drainage divides, and degree of escarpment retreat, we distinguish two overlapping areas of mountainous topography, a southern area related to late Oligocene to middle Miocene rifting and a northern area related to late Miocene to Quaternary rifting. The youthful topography in the northern area likely results from mechanical unloading of the footwall of the Amer-Brugent normal fault. In the southern area (encompassing the Catalan Coastal Ranges), erosion continuously renews topography produced by rifting while causing headward erosion of coastal rivers into the Ebro basin. Elevated topography along the Catalan margin derives principally from flexural isostatic rebound due to tectonic and erosional denudation, causing exhumation of the rifted margin. Nonetheless, the height of the mountains and the thinness of the crust suggest an additional component of dynamic or thermal support of mountainous topography, likely buoyancy forces from density differences in the mantle. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Barcelona, Dept Estratigrafia & Paleontol, E-08028 Barcelona, Spain. CSIC, Inst Earth Sci Jaume Almera, E-08028 Barcelona, Spain. RP Lewis, CJ (reprint author), Univ Calif Los Alamos Natl Lab, EES 1,MS D462, Los Alamos, NM 87545 USA. RI Verges, Jaume/D-3070-2011 OI Verges, Jaume/0000-0002-4467-5291 NR 84 TC 37 Z9 38 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0278-7407 J9 TECTONICS JI Tectonics PD FEB PY 2000 VL 19 IS 1 BP 86 EP 102 DI 10.1029/1999TC900056 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 284DL UT WOS:000085315400005 ER PT J AU Horstemeyer, MF Lathrop, J Gokhale, AM Dighe, M AF Horstemeyer, MF Lathrop, J Gokhale, AM Dighe, M TI Modeling stress state dependent damage evolution in a cast Al-Si-Mg aluminum alloy SO THEORETICAL AND APPLIED FRACTURE MECHANICS LA English DT Article ID DUCTILE FRACTURE; VOID GROWTH; METALS; CRITERIA; STEEL AB Internal state variable rate equations are cast in a continuum framework to model void nucleation, growth, and coalescence in a cast Al-Si-Mg aluminum alloy. The kinematics and constitutive relations for damage resulting from void nucleation, growth, and coalescence are discussed. Because damage evolution is intimately coupled with the stress state, internal state variable hardening rate equations are developed to distinguish between compression, tension, and torsion straining conditions. The scalar isotropic hardening equation and second rank tensorial kinematic hardening equation from the Bammann-Chiesa-Johnson (BCJ) Plasticity model are modified to account for hardening rate differences under tension, compression, and torsion. A method for determining the material constants for the plasticity and damage equations is presented. Parameter determination for the proposed phenomenological nucleation rate equation, motivated from fracture mechanics and microscale physical observations, involves counting nucleation sites as a function of strain from optical micrographs. Although different void growth models can be included, the McClintock void growth model is used in this study. A coalescence model is also introduced. The damage framework is then evaluated with respect to experimental tensile data of notched Al-Si-Mg cast aluminum alloy specimens. Finite element results employing the damage framework are shown to illustrate its usefulness. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Ctr Mat & Engn Sci, Livermore, CA 94551 USA. Georgia Inst Technol, Atlanta, GA 30332 USA. RP Horstemeyer, MF (reprint author), Sandia Natl Labs, Ctr Mat & Engn Sci, MS 9405,7011 E Ave, Livermore, CA 94551 USA. EM mfhorst@sandia.gov OI Horstemeyer, Mark/0000-0003-4230-0063 NR 31 TC 116 Z9 117 U1 4 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8442 EI 1872-7638 J9 THEOR APPL FRACT MEC JI Theor. Appl. Fract. Mech. PD FEB-MAR PY 2000 VL 33 IS 1 BP 31 EP 47 DI 10.1016/S0167-8442(99)00049-X PG 17 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 301BD UT WOS:000086287500005 ER PT J AU Garrett, BC AF Garrett, BC TI Perspective on "The transition state method" - Wigner E (1938) Trans Faraday Soc 34 : 29-41 SO THEORETICAL CHEMISTRY ACCOUNTS LA English DT Article DE transition-state theory (TST); variational TST (VTST); fundamental assumption of TST; quantum mechanical TST ID CLASSICAL MECHANICAL THEORY; CHEMICAL-REACTION RATES; COLLINEAR REACTIONS; NONSEPARABLE SYSTEMS; HYDROGEN MOLECULES; VARIATIONAL THEORY; RATE CONSTANTS; APPROXIMATION; MODEL; PATH AB A perspective is provided on Wigner's classic paper on transition-state theory (TST). After providing a brief review of the historical context of this work, we review its key contributions including Wigner's dynamical perspective on TST, the fundamental assumption of TST, and the upper-bound property of classical TST. A discussion is also presented of subsequent progress in the held, which was stimulated by this work. This progress includes the following: 1. Demonstrations of the validity of the fundamental assumption for classical systems. 2. Further investigations into the classical foundations of TST that helped elucidate relationships between classical trajectories and TST. 3. The development of a variational form of the theory. 4. The development of variational TST into a quantitative tool for predicting rate constants. 5. The search for an "exact" quantum mechanical version of TST. 6. The development of TST-like expressions for the exact quantum mechanical rate constant. 7. The extension of TST to reactions in condensed phases. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Garrett, BC (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Garrett, Bruce/F-8516-2011 NR 60 TC 24 Z9 24 U1 2 U2 13 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1432-881X J9 THEOR CHEM ACC JI Theor. Chem. Acc. PD FEB PY 2000 VL 103 IS 3-4 BP 200 EP 204 DI 10.1007/s002149900046 PG 5 WC Chemistry, Physical SC Chemistry GA 286AE UT WOS:000085419900010 ER PT J AU Miller, WH AF Miller, WH TI Using classical mechanics in a quantum framework. Perspective on "Semiclassical description of scattering" - Ford KW, Wheeler JA (1959) Ann Phys (NY) 7 : 259 SO THEORETICAL CHEMISTRY ACCOUNTS LA English DT Article DE semiclassical; scattering; quantum effects; interference; initial value representation AB Ford and Wheeler's paper on elastic scattering was the first to fully analyze the semiclassical limit of quantum mechanics for a collision process and thus reveal the nature of quantum corrections to classical mechanics therein. This "perspective" discusses the historical setting, the content, and present day implications of this work. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Miller, WH (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 5 TC 1 Z9 1 U1 2 U2 5 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1432-881X J9 THEOR CHEM ACC JI Theor. Chem. Acc. PD FEB PY 2000 VL 103 IS 3-4 BP 236 EP 237 DI 10.1007/s002140050023 PG 2 WC Chemistry, Physical SC Chemistry GA 286AE UT WOS:000085419900022 ER PT J AU Kouri, DJ Hoffman, DK AF Kouri, DJ Hoffman, DK TI Perspective on "Molecular collisions. VIII" - Curtiss CF (1968) J Chem Phys 49 : 1952-1957 SO THEORETICAL CHEMISTRY ACCOUNTS LA English DT Article DE centrifugal sudden approximation; infinite order sudden approximation; sudden approximations; inelastic collisions; rotationally inelastic collisions ID MOMENTUM DECOUPLING APPROXIMATIONS; DIFFERENTIAL CROSS-SECTIONS; COUPLED STATES APPROXIMATION; SUDDEN APPROXIMATION; HD-NE; QUANTUM; SCATTERING; FACTORIZATION; TRANSITIONS; PROPENSITY AB We present an overview of the influence of C.F. Curtiss on the theory of molecular collisions, as exemplified by the title paper. Both authors were graduate students of Curtiss and, as such, were strongly influenced by his ideas and approaches to theoretical chemistry. This resulted in a subsequent collaboration that provided the rigorous basis for understanding the success of the so-called centrifugal sudden and energy sudden approximations (the two combined being the "infinite order sudden" approximation). C1 Univ Houston, Dept Chem, Houston, TX 77204 USA. Univ Houston, Dept Phys, Houston, TX 77204 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Kouri, DJ (reprint author), Univ Houston, Dept Chem, Univ Pk, Houston, TX 77204 USA. NR 63 TC 2 Z9 2 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1432-881X J9 THEOR CHEM ACC JI Theor. Chem. Acc. PD FEB PY 2000 VL 103 IS 3-4 BP 281 EP 285 PG 5 WC Chemistry, Physical SC Chemistry GA 286AE UT WOS:000085419900035 ER PT J AU Prasad, SV Walck, SD Zabinski, JS AF Prasad, SV Walck, SD Zabinski, JS TI Microstructural evolution in lubricious ZnO films grown by pulsed laser deposition SO THIN SOLID FILMS LA English DT Article DE coatings; electron microscopy; tribology; zinc oxide ID SPUTTERED ZINC-OXIDE; TRIBOLOGICAL BEHAVIOR; RF; ORIENTATION; TEMPERATURE AB Zinc oxide (ZnO) is well known to the electronic industry as a piezoelectric material. Recent research from this laboratory also indicates the potential of ZnO as a tribological material. The current work describes the evolution of microstructure with deposition parameters in pulsed laser deposited ZnO thin films, specifically targeted for friction and wear applications. Films were characterized by high resolution scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Friction and wear measurements were made using a ball-on-disk tribometer. Films were grown in vacuum (V) as well as in 5 mTorr of oxygen (O-2), while the substrates were kept at room temperature (RT). The RT/V ZnO films have (002) columnar texture with an average column width of 20 nm. The RT/O-2 films also are nanoclumnar with (002) texture, but each column is a mosaic of low-angle boundaries. Deformation mechanisms associated with nanocrystalline grain structure were analyzed with particular reference to sliding contact. Mechanisms to provide the observed low friction of RT/O-2 films (mu = 0.15-0.20) have been activated by its mosaic structure. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. PPG Ind, Pittsburgh, PA 15238 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Prasad, SV (reprint author), Sandia Natl Labs, POB 5800,MS 1407, Albuquerque, NM 87185 USA. NR 36 TC 62 Z9 69 U1 5 U2 20 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 FEB 1 PY 2000 VL 360 IS 1-2 BP 107 EP 117 DI 10.1016/S0040-6090(99)00880-9 PG 11 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 285ZQ UT WOS:000085418600019 ER PT J AU Dai, ZY Hooker, BS Anderson, DB Thomas, SR AF Dai, ZY Hooker, BS Anderson, DB Thomas, SR TI Expression of Acidothermus cellulolyticus endoglucanase E1 in transgenic tobacco: biochemical characteristics and physiological effects SO TRANSGENIC RESEARCH LA English DT Article DE Acidothermus cellulolyticus; cellulase; endoglucanase (E1); Nicotiana tabacum; heterologous expression; leaf specific promoter RbcS-3C; chloroplast transit peptide RbcS-2A; alfalfa mosaic virus 5 '-untranslated leader ID HALOPHYTE MESEMBRYANTHEMUM-CRYSTALLINUM; CRASSULACEAN ACID METABOLISM; FUEL ETHANOL; TI-PLASMID; INDUCTION; PHOTOSYNTHESIS; CELLULASES; GENES AB The expression of the Acidothermus cellulolyticus endoglucanase F1 gene in transgenic tobacco (Nicotiana tabacum) was examined in this study, where F1 coding sequence was transcribed under the control of a leaf specific Rubisco small subunit promoter (tomato RbcS-3C). Targeting the F1 protein to the chloroplast was established using a chloroplast transit peptide of Rubisco small subunit protein (tomato RbcS-2A) and confirmed by immunocytochemistry. The E1 produced in transgenic tobacco plants was found to be biologically active, and to accumulate in leaves at levels of up to 1.35% of total soluble protein. Optimum temperature and pH for F1 enzyme activity in leaf extracts were 81 degrees C and 5.25, respectively. F1 activity remained constant on a gram fresh leaf weight basis, but dramatically increased on a total leaf soluble protein basis as leaves aged, or when leaf discs were dehydrated. F1 protein in old leaves, or after 5 h dehydration, was partially degraded although F1 activity remained constant. Transgenic plants exhibited normal growth and developmental characteristics with photosynthetic rates similar to those of untransformed SR1 tobacco plants. Results from these biochemical and physiological analyses suggest that the chloroplast is a suitable cellular compartment for accumulation of the hydrolytic F1 enzyme. C1 Pacific NW Lab, Environm Technol Div, Bioproc Grp, Richland, WA 99352 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Dai, ZY (reprint author), Pacific NW Lab, Environm Technol Div, Bioproc Grp, POB 999,K2-10,MSIN, Richland, WA 99352 USA. NR 28 TC 63 Z9 68 U1 0 U2 14 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0962-8819 J9 TRANSGENIC RES JI Transgenic Res. PD FEB PY 2000 VL 9 IS 1 BP 43 EP 54 DI 10.1023/A:1008922404834 PG 12 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 322BW UT WOS:000087491200005 PM 10853268 ER PT J AU Xiong, DM AF Xiong, DM TI A three-stage computational approach to network matching SO TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES LA English DT Article DE network matching; spatial data integration; three-stage computation; GIS ID IMAGERY AB Network matching is frequently needed for integrating data that come from different sources. Traditional ways of finding correspondences between networks are time-consuming and require considerable manual manipulation. This pager describes a three-stage matching algorithm (node matching, segment matching, and edge matching) that combines bottom-up and top-down procedures to carry out the matching computation. As it uses sensitive matching measures, the proposed algorithm promises good improvement to existing algorithms. An experiment of matching two waterway networks is reported in the paper. The results of this experiment demonstrate that a reasonable matching rate and good computational efficiency can be achieved with this algorithm. The paper also briefly discusses necessary improvements in areas of linear alignment, aspatial matching and higher-level matching. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, ITS Res Program, Oak Ridge, TN 37831 USA. RP Xiong, DM (reprint author), Oak Ridge Natl Lab, ITS Res Program, 1000 Bethel Valley Rd,MS 6206, Oak Ridge, TN 37831 USA. NR 15 TC 19 Z9 22 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0968-090X J9 TRANSPORT RES C-EMER JI Transp. Res. Pt. C-Emerg. Technol. PD FEB-DEC PY 2000 VL 8 IS 1-6 BP 71 EP 89 DI 10.1016/S0968-090X(00)00011-5 PG 19 WC Transportation Science & Technology SC Transportation GA 356JZ UT WOS:000089441300006 ER PT J AU Southworth, F Peterson, BE AF Southworth, F Peterson, BE TI Intermodal and international freight network modeling SO TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES LA English DT Article DE intermodal freight; networks; geographic information systems; traffic routing ID FLOWS AB The authors describe the development and application of a single, integrated digital representation of a multimodal and transcontinental freight transportation network. The network was constructed to support the simulation of some five million origin to destination freight shipments reported as part of the 1997 United States Commodity Flow Survey. The paper focuses on the routing of the tens of thousands of intermodal freight movements reported in this survey. Routings involve different combinations of truck, rail and water transportation. Geographic information systems (GIS) technology was invaluable in the cost-effective construction and maintenance of this network and in the subsequent validation of mode sequences and route selections. However, computationally efficient routing of internodal freight shipments was found to be most efficiently accomplished outside the GIS. Selection of appropriate intermodal routes required procedures for linking freight origins and destinations to the transportation network, procedures for modeling intermodal terminal transfers and inter-carrier interlining practices, and a procedure for generating multimodal impedance functions to reflect the relative costs of alternative, survey reported mode sequences. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Ctr Transportat Anal, Oak Ridge, TN 37831 USA. RP Southworth, F (reprint author), Oak Ridge Natl Lab, Ctr Transportat Anal, POB 2008, Oak Ridge, TN 37831 USA. NR 18 TC 82 Z9 86 U1 5 U2 28 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0968-090X J9 TRANSPORT RES C-EMER JI Transp. Res. Pt. C-Emerg. Technol. PD FEB-DEC PY 2000 VL 8 IS 1-6 BP 147 EP 166 DI 10.1016/S0968-090X(00)00004-8 PG 20 WC Transportation Science & Technology SC Transportation GA 356JZ UT WOS:000089441300010 ER PT J AU Britton, CL Jones, RL Oden, PI Hu, Z Warmack, RJ Smith, SF Bryan, WL Rochelle, JM AF Britton, CL Jones, RL Oden, PI Hu, Z Warmack, RJ Smith, SF Bryan, WL Rochelle, JM TI Multiple-input microcantilever sensors SO ULTRAMICROSCOPY LA English DT Article; Proceedings Paper CT 1st International Conference on Scanning Probe Microscopy, Cantilever Sensors and Nanostructures CY MAY 30-JUN 01, 1999 CL SEATTLE, WASHINGTON DE multiple-input chemical sensing; microcantilever; absorption-induced stress AB A surface-micromachined micro-electro-mechanical-system (MEMS) process has been used to demonstrate multiple-input chemical sensing using selectively coated cantilever arrays. Cantilever motion due to absorption-induced stress was readout using a custom-designed, eight-channel integrated circuit. Combined hydrogen and mercury vapor detection was achieved with a palm-sized, self-powered module with spread-spectrum telemetry reporting. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN 37996 USA. RP Warmack, RJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Hu, Zhiyu/J-7742-2013 NR 7 TC 82 Z9 86 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD FEB PY 2000 VL 82 IS 1-4 BP 17 EP 21 DI 10.1016/S0304-3991(99)00155-2 PG 5 WC Microscopy SC Microscopy GA 288FF UT WOS:000085551100004 ER PT J AU Datskos, PG Rajic, S Datskou, I AF Datskos, PG Rajic, S Datskou, I TI Detection of infrared photons using the electronic stress in metal-semiconductor cantilever interfaces SO ULTRAMICROSCOPY LA English DT Article; Proceedings Paper CT 1st International Conference on Scanning Probe Microscopy, Cantilever Sensors and Nanostructures CY MAY 30-JUN 01, 1999 CL SEATTLE, WASHINGTON ID MICROCANTILEVERS; RESOLUTION; SILICON; SENSORS AB We report on a new method for detecting photons using the stress caused by photoelectrons emitted from a metal film surface in contact with a semiconductor microstructure which forms a Schottky barrier. The detection of photons results from measuring the photo-induced bending of the Schottky barrier microstructure due to electronic stress produced by photoelectrons diffusing into the microstructure. Internal photoemission has been used in the past to detect photons, however, in those cases the detection was accomplished by measuring the current due to photoelectrons and not due to electronic stress. In this work we studied the photon response of 500 nm thick Si microcantilevers coated with a 30 nm layer of Pt. Photons with sufficient energies produce electrons from the platinum-silicon interface which diffuse into the Si and produce an electronic stress. Since the excess charge carriers cause the Si microcantilever to contract in length but not the Pt layer, the bimaterial microcantilever bends. The charge carriers responsible for the photo-induced stress in Si, were produced via internal photoemission using a diode laser with wavelength lambda = 1550 nm. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN 37996 USA. Environm Engn Grp Inc, Knoxville, TN 37931 USA. RP Datskos, PG (reprint author), Oak Ridge Natl Lab, Bear Breek Rd,POB 2008, Oak Ridge, TN 37831 USA. NR 28 TC 17 Z9 18 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD FEB PY 2000 VL 82 IS 1-4 BP 49 EP 56 DI 10.1016/S0304-3991(99)00140-0 PG 8 WC Microscopy SC Microscopy GA 288FF UT WOS:000085551100008 ER PT J AU Lee, I Evans, BR Woodward, J AF Lee, I Evans, BR Woodward, J TI The mechanism of cellulase action on cotton fibers: evidence from atomic force microscopy SO ULTRAMICROSCOPY LA English DT Article; Proceedings Paper CT 1st International Conference on Scanning Probe Microscopy, Cantilever Sensors and Nanostructures CY MAY 30-JUN 01, 1999 CL SEATTLE, WASHINGTON DE cotton fibers; cellulase action; tapping mode atomic force microscopy (TMAFM) ID REESEI CELLOBIOHYDROLASE-I; TRICHODERMA-REESEI; ENDOGLUCANASE; ENZYME; PALLADIUM; QM-9414; DOMAIN AB Two cellulases from Trichoderma reesei - an exoglucanase, CBH I, and an endoglucanase, EG II - alone and in combination were incubated with cotton fibers. The effects of the cellulases on the surfaces of the cotton fibers were examined by atomic force microscopy. At high magnification, the physical effects on the fibers caused by the two types of enzymes were considerably different. Treatment with CBH I resulted in the appearance of distinct pathways or tracks along the length of the macrofibril. Treatment with EG II appeared to cause peeling and smoothing of the fiber surface. In combination, their effect was observed to be greatest when both enzymes were present simultaneously. When fibers smoothed by treatment with EG II were treated subsequently with CBH I, further evidence of path way formation caused by the action of CBH I along the fibers was observed. Incubation with a cellulase from Thermotoga maritima that lacks a cellulose binding domain had no effect on the surface of cotton fibers. These images provide the first physical evidence of differences in the effect of cellulase components action on the surface of cotton fibers and provide evidence for the movement or tracking of CBH I along the fibers. The first AFM image of CBH I molecules are presented. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Elect Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Lee, I (reprint author), Univ Tennessee, Dept Elect Engn, Knoxville, TN 37996 USA. NR 23 TC 86 Z9 96 U1 2 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD FEB PY 2000 VL 82 IS 1-4 BP 213 EP 221 DI 10.1016/S0304-3991(99)00158-8 PG 9 WC Microscopy SC Microscopy GA 288FF UT WOS:000085551100029 PM 10741672 ER PT J AU Hoyt, PR Doktycz, MJ Modrich, P Warmack, RJ Allison, DP AF Hoyt, PR Doktycz, MJ Modrich, P Warmack, RJ Allison, DP TI Identifying sequence similarities between DNA molecules SO ULTRAMICROSCOPY LA English DT Article; Proceedings Paper CT 1st International Conference on Scanning Probe Microscopy, Cantilever Sensors and Nanostructures CY MAY 30-JUN 01, 1999 CL SEATTLE, WASHINGTON DE atomic force microscope; heteroduplex; genomic research; sequence verification ID ATOMIC-FORCE MICROSCOPY; ECORI ENDONUCLEASE; ESCHERICHIA-COLI; PLASMID DNA; PROTEIN; AIR AB An atomic force microscope (AFM) imaging technique is described to compare sequences between two different DNA molecules and precisely locate nonhomologies in DNA strands. Sequence comparisons are made by forming heteroduplexes between the two molecules and, by AFM imaging the intact molecules formed, identifying both homologous and nonhomologous regions. By forming heteroduplexes between linearized wildtype pSV-beta-galactosidase plasmid (6821 bp) and a series of deletion mutants we have identified nonhomologies (deletions) as small as 22 bp and as large as 418 bp. Furthermore, by incorporating our technique for AFM-mediated restriction mapping of DNA these mutations can be positioned relative to EcoRI restriction sites. These results suggest AFM can be useful in identifying molecular level similarities and differences in DNA. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Duke Univ, Howard Hughes Med Inst, Dept Biochem, Durham, NC 27710 USA. RP Allison, DP (reprint author), Oak Ridge Natl Lab, Div Life Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Doktycz, Mitchel/A-7499-2011 OI Doktycz, Mitchel/0000-0003-4856-8343 NR 25 TC 5 Z9 5 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD FEB PY 2000 VL 82 IS 1-4 BP 237 EP 244 DI 10.1016/S0304-3991(99)00153-9 PG 8 WC Microscopy SC Microscopy GA 288FF UT WOS:000085551100032 PM 10741675 ER PT J AU Miller, DL Gies, RA AF Miller, DL Gies, RA TI The influence of ultrasound frequency and gas-body composition on the contrast agent-mediated enhancement of vascular bioeffects in mouse intestine SO ULTRASOUND IN MEDICINE AND BIOLOGY LA English DT Article DE ultrasound; bioeffects; petechiae; hemorrhage; hyperemia; cavitation; mechanical index; Albunex((R)); Optison((R)); Levovist((R)); PESDA; contrast agent adverse effects; gas-body activation ID PIEZOELECTRIC LITHOTRIPTER; HEMORRHAGE; CAVITATION; EXPOSURE; ALBUMIN; FIELDS AB The induction by ultrasound (US) of petechiae and hemorrhages in mouse intestine was examined with injection of gas body-based contrast agents, Production of petechiae in the intestinal wall was enhanced by contrast agents for both continuous and pulsed (10 mu s pulses repeated at 1 kHz) exposure relative to a gas body-free blank. For pulsed exposure with 10 mL/kg of Albunex(R), apparent thresholds for peak negative pressure amplitude were 0.42 MPa at 0.4 MHz, 0.85 MPa at 1.09 MHz and 2.3 MPa at 2.4 MHz, Results at these frequencies were the same for 10-11 cycle pulses with fixed duty cycle (0.01). Thresholds for hemorrhage into the intestinal lumen were not appreciably enhanced by added Albunex(R), and appear to be compatible with previously reported lithotripsy data when duty factor differences are considered. The agents PESDA, Optison(R) and Levovist(R) had lower thresholds (for example, 1.8 MPa for Levovist(R)) than Albunex(R) at 2.3 MHz, and yielded more petechiae, The thresholds for petechiae induction by US with contrast agents encroach upon the exposure range relevant to diagnostic US practice. (C) 2000 World Federation for Ultrasound in Medicine & Biology. C1 Univ Michigan, Ctr Med, Ann Arbor, MI 48109 USA. Battelle Pacific NW Natl Lab, Richland, WA USA. RP Miller, DL (reprint author), Univ Michigan, Ctr Med, Room 3315 Kresge 3,200 Zina Pitcher Pl, Ann Arbor, MI 48109 USA. FU NCI NIH HHS [CA42947] NR 19 TC 59 Z9 67 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0301-5629 J9 ULTRASOUND MED BIOL JI Ultrasound Med. Biol. PD FEB PY 2000 VL 26 IS 2 BP 307 EP 313 DI 10.1016/S0301-5629(99)00138-6 PG 7 WC Acoustics; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Radiology, Nuclear Medicine & Medical Imaging GA 294WX UT WOS:000085934400016 PM 10722920 ER PT J AU Prasad, SV McDevitt, NT Zabinski, JS AF Prasad, SV McDevitt, NT Zabinski, JS TI Tribology of tungsten disulfide-nanocrystalline zinc oxide adaptive lubricant films from ambient to 500 degrees C SO WEAR LA English DT Article DE tribology; tungsten disulfide; zinc oxide ID TRANSMISSION ELECTRON-MICROSCOPY; RAMAN-SPECTROSCOPY; BEHAVIOR; TEMPERATURES; CHEMISTRY AB Tungsten disulfide (WS2)-zinc oxide (ZnO) composite is a candidate material that exhibits adaptive lubricant behavior. Adaptive lubricants undergo chemical changes with changing environment to provide lubrication in extreme environments. In the current study, the tribological characteristics of WS2-nanocrystalline ZnO films have been investigated from ambient to 500 degrees C. The composite films were powder burnished on inconel substrates. Using a bah-on-flat tribometer, friction tests were conducted on WS2-ZnO nanocomposite films containing 50% by weight of the oxide. For comparison, measurements were made on pure WS2 films burnished under identical conditions. The room temperature tests were performed in dry nitrogen, while the elevated temperature tests were run in air. Wear scars and transfer films on the counterface were analyzed by scanning electron microscopy, energy dispersive X-ray spectroscopy and Raman spectroscopy. Results showed that the nanocrystalline ZnO additive resulted in significant reduction in friction coefficient of WS, both at 300 degrees C as well as at room temperature. Third-body analyses from 300 degrees C tears revealed that tribooxidation is less prevalent in nanocomposite films. At 500 degrees C, the friction coefficient of pure WS2 films increased to 0.50 within the first 2000 cycles, whereas the nanocomposite films lasted the. entire duration of 10,000 cycles with steady state friction coefficient of 0.22. Raman spectroscopy identified the formation of zinc tungstate (ZnWO4) during the 500 degrees C triborests, confirming the adaptive lubricant concept in WS2-ZnO nanocomposites. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. RAMSPEC Res, Dayton, OH 45431 USA. USAF, Res Lab, AFRL, MLBT, Wright Patterson AFB, OH 45433 USA. RP Sandia Natl Labs, MS 1407,POB 5800, Albuquerque, NM 87111 USA. EM svprasa@sandia.gov NR 32 TC 52 Z9 64 U1 3 U2 19 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 EI 1873-2577 J9 WEAR JI Wear PD FEB PY 2000 VL 237 IS 2 BP 186 EP 196 DI 10.1016/S0043-1648(99)00329-4 PG 11 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 295AV UT WOS:000085944500004 ER PT J AU Vitek, JM Iskander, YS Oblow, EM AF Vitek, JM Iskander, YS Oblow, EM TI Improved ferrite number prediction in stainless steel arc welds using artificial neural networks - Part 1: Neural network development SO WELDING JOURNAL LA English DT Article ID SOLIDIFICATION; ALLOYS; METAL AB Neural network modeling is a powerful nonlinear regression analysis method that is extremely useful in identifying behavioral trends. This methodology was applied to the problem of predicting Ferrite Number in arc welds as a function of composition. This paper describes the details of the development of the neural network model, named FNN-1999, including the identification of the optimum network architecture and network parameters. The model was trained on the same data as the WRC-1992 constitution diagram and covers a range of Ferrite Numbers from 0 to 117, with a corresponding wide range in composition. Results of the model are presented in Part 2. It is shown that the accuracy of the FNN-1999 model in predicting Ferrite Number is superior to the accuracy of other models that are currently available, including the WRC-1992 diagram. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Georgia Inst Technol, Atlanta, GA 30332 USA. RP Vitek, JM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 29 TC 14 Z9 15 U1 0 U2 1 PU AMER WELDING SOC PI MIAMI PA PO BOX 351040, MIAMI, FL 33135 USA SN 0043-2296 J9 WELD J JI Weld. J. PD FEB PY 2000 VL 79 IS 2 BP 33S EP 40S PG 8 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 279RQ UT WOS:000085059300013 ER PT J AU Vitek, JM Iskander, YS Oblow, EM AF Vitek, JM Iskander, YS Oblow, EM TI Improved ferrite number prediction in stainless steel arc welds using artificial neural networks - Part 2: Neural network results SO WELDING JOURNAL LA English DT Article ID SOLIDIFICATION; ALLOYS AB The development of a neural network model, named FNN-1999, for predicting Ferrite Number in are welds as a function of alloy composition is described in Part 1. In this paper, the results of the model are compared to other means of predicting Ferrite Number in stainless steel welds. It was found the accuracy of the FNN-1999 model in predicting Ferrite Number is superior to that of the WRC-1992 diagram, the Function Fit model and a preliminary neural network model developed earlier. The error in fitting the current model to the training set was 40% less than that for the WRC-1992 diagram. In addition, the FNN-1999 model removes the restriction found in WRC-1992 and many other constitution diagrams that each element's contribution to the Ferrite Number is constant, regardless of the overall composition. Examples are given that show that with this added flexibility of the FNN-1999 model, the impact of alloying additions varies as a function of concentration, and in some cases the variation can be quite significant. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Georgia Inst Technol, Atlanta, GA 30332 USA. RP Vitek, JM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 23 TC 16 Z9 17 U1 0 U2 0 PU AMER WELDING SOC PI MIAMI PA PO BOX 351040, MIAMI, FL 33135 USA SN 0043-2296 J9 WELD J JI Weld. J. PD FEB PY 2000 VL 79 IS 2 BP 41S EP 50S PG 10 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 279RQ UT WOS:000085059300014 ER PT J AU Kim, J Boyd, JT Jackson, HE Choquette, KD AF Kim, J Boyd, JT Jackson, HE Choquette, KD TI Near-field spectroscopy of selectively oxidized vertical cavity surface emitting lasers SO APPLIED PHYSICS LETTERS LA English DT Article ID OXIDATION AB Selectively oxidized vertical cavity surface emitting lasers (VCSELs) have been studied by spectrally resolved near-field scanning optical microscopy. We have obtained spatially and spectrally resolved images of both subthreshold emission and lasing emission from a selectively oxidized VCSEL operating at a wavelength of 850 nm. Below threshold, highly local high gain regions, emitting local intensity maxima within the active area, were observed; these were found to serve as lasing centers just above threshold. Above threshold, the near-field spatial modal distributions of low order transverse modes were identified by spectrally analyzing the emission; these were found to be complex and somewhat different from those measured in the far field. (C) 2000 American Institute of Physics. [S0003-6951(00)00105-4]. C1 Univ Cincinnati, Dept Phys, Cincinnati, OH 45221 USA. Sandia Natl Labs, Photon Res Dept, Albuquerque, NM 87185 USA. Univ Cincinnati, Dept Elect & Comp Engn & Comp Sci, Cincinnati, OH USA. RP Kim, J (reprint author), Univ Cincinnati, Dept Phys, Cincinnati, OH 45221 USA. RI Jackson, Howard/K-4881-2012; Kim, Jeongyong/F-2132-2013 NR 11 TC 21 Z9 21 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 31 PY 2000 VL 76 IS 5 BP 526 EP 528 DI 10.1063/1.125807 PG 3 WC Physics, Applied SC Physics GA 277NB UT WOS:000084938700002 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 Ortho-molecular hydrogen in hydrogenated amorphous silicon SO APPLIED PHYSICS LETTERS LA English DT Article ID A-SI-H; PROTON-MAGNETIC-RESONANCE; ALPHA-SI; FILMS; H-2; NMR AB Using a Jeener-Broekaert three-pulse sequence to measure directly the concentration of o-H-2 by H-1 nuclear magnetic resonance (NMR), we find that this concentration is one order of magnitude larger than that previously inferred from spin-lattice relaxation time (T-1) measurements. At 300 K, this concentration of o-H-2 contributes at most 30% to the narrow H-1 NMR line attributed to hydrogen bonded to silicon. For a plasma-enhanced-chemical-vapor-deposition (PECVD) sample, two distinct values of T-1 for o-H-2 are found, only one of which contributes to the T-1 for bonded hydrogen. In hot-wire-chemical-vapor-deposition samples, the line shape of o-H-2 exhibits motional narrowing at lower temperatures, suggesting a more ordered structure than in a typical PECVD sample. (C) 2000 American Institute of Physics. [S0003-6951(00)02105-7]. C1 Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Su, TN (reprint author), Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 31 PY 2000 VL 76 IS 5 BP 565 EP 567 DI 10.1063/1.125818 PG 3 WC Physics, Applied SC Physics GA 277NB UT WOS:000084938700015 ER PT J AU Im, J Auciello, O Baumann, PK Streiffer, SK Kaufman, DY Krauss, AR AF Im, J Auciello, O Baumann, PK Streiffer, SK Kaufman, DY Krauss, AR TI Composition-control of magnetron-sputter-deposited (BaxSr1-x)Ti1+yO3+z thin films for voltage tunable devices SO APPLIED PHYSICS LETTERS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION AB Precise control of composition and microstructure is critical for the production of (BaxSr1-x)Ti1+yO3+z (BST) dielectric thin films with the large dependence of permittivity on electric field, low losses, and high electrical breakdown fields that are required for successful integration of BST into tunable high-frequency devices. Here, we present results on composition-microstructure-electrical property relationships for polycrystalline BST films produced by magnetron-sputter deposition, that are appropriate for microwave and millimeter-wave applications such as varactors and frequency triplers. Films with controlled compositions were grown from a stoichiometric Ba0.5Sr0.5TiO3 target by control of the background processing gas pressure. It was determined that the (Ba+Sr)/Ti ratios of these BST films could be adjusted from 0.73 to 0.98 by changing the total (Ar+O-2) process pressure, while the O-2/Ar ratio did not strongly affect the metal ion composition. Film crystalline structure and dielectric properties as a function of the (Ba+Sr)/Ti ratio are discussed. Optimized BST films yielded capacitors with low dielectric losses (0.0047), among the best reported for sputtered BST, while still maintaining tunabilities suitable for device applications. (C) 2000 American Institute of Physics. [S0003-6951(00)01705-8]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Im, J (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Streiffer, Stephen/A-1756-2009 NR 18 TC 226 Z9 241 U1 3 U2 25 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 31 PY 2000 VL 76 IS 5 BP 625 EP 627 DI 10.1063/1.125839 PG 3 WC Physics, Applied SC Physics GA 277NB UT WOS:000084938700035 ER PT J AU Gao, C Duewer, F Xiang, XD AF Gao, C Duewer, F Xiang, XD TI Quantitative microwave evanescent microscopy (vol 75, pg 3005, 1999) SO APPLIED PHYSICS LETTERS LA English DT Correction C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Gao, C (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Xiang, Xiaodong/A-9445-2012; Xiang, Xiaodong/A-5936-2017 NR 1 TC 2 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 31 PY 2000 VL 76 IS 5 BP 656 EP 656 DI 10.1063/1.125850 PG 1 WC Physics, Applied SC Physics GA 277NB UT WOS:000084938700046 ER PT J AU Howard, CJ Kennedy, BJ Chakoumakos, BC AF Howard, CJ Kennedy, BJ Chakoumakos, BC TI Neutron powder diffraction study of rhombohedral rare-earth aluminates and the rhombohedral to cubic phase transition SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID ORDER AB Neutron powder diffraction has been used to examine the structural changes of the rare-earth aluminates LaAlO3, PrAlO3 and NdAlO3 over a wide range of temperatures. At room temperature, all three aluminates adopt the rhombohedral perovskite structure in space group R (3) over bar c (a = 5.3647(1) Angstrom, c = 13.1114(3) Angstrom for LaAlO3, a = 5.3337(2) Angstrom, c = 12.9842(4) Angstrom for PrAlO3, a = 5.3223(2) Angstrom, c = 12.9292(5) Angstrom for NdAlO3). The rhombohedral structure is characterized by rotation of the oxygen atom octahedra about the threefold axis, and compression of these octahedra parallel to the same axis. As the temperature is increased, the rotation angle and the compression decrease, indicative of an approach to the cubic symmetry of the ideal perovskite. Only for LaAlO3, however. was the transition at a low enough temperature to unequivocally obtain the cubic phase. For PrAlO3 the transition was closely approached before the sample can failed, but for NdAlO3 the transition appeared to be inaccessible within the available temperature range. The rotation angle is taken to represent the order parameter, and its temperature variation is well described by a generalized mean field approach. Such a description suggests the transitions are continuous, being at 820 K and second order for the transition in LaAlO3, and at 1768 K and tricritical for the transition in PrAlO3. In the proximity of the phase transition, the octahedral compression varies with the square of the rotation angle, though this description is inadequate remote from the transition, and the constant of proportionality is different for the different compounds. C1 Univ Sydney, Sch Chem, Sydney, NSW 2006, Australia. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Howard, CJ (reprint author), Univ Sydney, Sch Chem, Sydney, NSW 2006, Australia. RI Howard, Christopher/B-5138-2009; Chakoumakos, Bryan/A-5601-2016; OI Chakoumakos, Bryan/0000-0002-7870-6543; Kennedy, Brendan/0000-0002-7187-4579 NR 37 TC 176 Z9 177 U1 4 U2 36 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 JAN 31 PY 2000 VL 12 IS 4 BP 349 EP 365 DI 10.1088/0953-8984/12/4/301 PG 17 WC Physics, Condensed Matter SC Physics GA 281UN UT WOS:000085179300003 ER PT J AU Eitel, K AF Eitel, K TI Compatibility analysis of the LSND evidence and the KARMEN exclusion for (nu)over-bar(mu)->(nu)over-bar(e) SO NEW JOURNAL OF PHYSICS LA English DT Article ID NUCLEAR-POWER-REACTOR; NEUTRINO OSCILLATIONS; PHYSICS; SEARCH AB A combined statistical analysis of the experimental results of the LSND and KARMEN <()over bar>(mu) --> <()over bar>(e) oscillation search is presented. LSND has evidence for neutrino oscillations that is not confirmed by the KARMEN experiment. However, there is a region in the (sin(2) (2 circle minus), Deltam(2)) parameter space where the results of both experiments are statistically compatible. This joint analysis is based on likelihood functions for both data sets. A frequentist approach to creating Monte Carlo samples analogous to the experimental outcome is applied to deduce correct confidence limits. Different schemes of combination can be chosen to provide correct coverage which leads to slightly different confidence regions in (sin(2)(2 circle minus), Deltam(2)). C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Eitel, K (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM klaus@ik1.fzk.de NR 19 TC 44 Z9 44 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 1367-2630 J9 NEW J PHYS JI New J. Phys. PD JAN 31 PY 2000 VL 2 BP 11 EP 125 AR 1 DI 10.1088/1367-2630/2/1/301 PG 25 WC Physics, Multidisciplinary SC Physics GA 412ZT UT WOS:000167586000001 ER PT J AU Burkert, VD AF Burkert, VD TI Probing the structure of nucleons in electromagnetic interactions SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID GERASIMOV-DRELL-HEARN; SUM-RULE AB I discuss open problems in nucleon structure studies using electromagnetic probes. The focus is on the regime of strong interaction QCD. Significant progress in our understanding of the nucleon structure in the region of strong QCD may be expected in the first decade of the new millenium due to major experimental and theoretical efforts currently underway in this field. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Burkert, VD (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 18 TC 3 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 29C EP 37C DI 10.1016/S0375-9474(99)00569-2 PG 9 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100005 ER PT J AU Gagliardi, CA Awes, TC Beddo, ME Brooks, ML Brown, CN Bush, JD Carey, TA Chang, TH Cooper, WE Garvey, GT Geesaman, DF Hawker, EA He, XC Isenhower, LD Kaplan, DM Kaufman, SB Kirk, PN Koetke, DD Kyle, G Lee, DM Lee, WM Leitch, MJ Makins, N McGaughey, PL Moss, JM Mueller, BA Nord, PM Papavassiliou, V Park, BK Peng, JC Petitt, G Reimer, PE Sadler, ME Selden, J Sondheim, WE Stankus, PW Thompson, TN Towell, RS Tribble, RE Vasiliev, MA Wang, YC Wang, ZF Webb, JC Willis, JL Wise, DK Young, GR AF Gagliardi, CA Awes, TC Beddo, ME Brooks, ML Brown, CN Bush, JD Carey, TA Chang, TH Cooper, WE Garvey, GT Geesaman, DF Hawker, EA He, XC Isenhower, LD Kaplan, DM Kaufman, SB Kirk, PN Koetke, DD Kyle, G Lee, DM Lee, WM Leitch, MJ Makins, N McGaughey, PL Moss, JM Mueller, BA Nord, PM Papavassiliou, V Park, BK Peng, JC Petitt, G Reimer, PE Sadler, ME Selden, J Sondheim, WE Stankus, PW Thompson, TN Towell, RS Tribble, RE Vasiliev, MA Wang, YC Wang, ZF Webb, JC Willis, JL Wise, DK Young, GR CA FNAL E866 NuSea Collaboration TI Light antiquark flavor asymmetry in the nucleon sea SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID NN FORM-FACTOR; PARTON DISTRIBUTIONS; QUARK DISTRIBUTIONS; SYMMETRY-BREAKING; GOTTFRIED SUM; ORIGIN C1 Abilene Christian Univ, Abilene, TX 79699 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Georgia State Univ, Atlanta, GA 30303 USA. IIT, Chicago, IL 60616 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. New Mexico State Univ, Las Cruces, NM 88003 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Texas A&M Univ, College Stn, TX 77843 USA. Valparaiso Univ, Valparaiso, IN USA. RP Abilene Christian Univ, Abilene, TX 79699 USA. EM cggroup@comp.tamu.edu; dbkaplan@phys.washington.edu; tribble@comp.tamu.edu RI Reimer, Paul/E-2223-2013 NR 19 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 EI 1873-1554 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 284C EP 287C DI 10.1016/S0375-9474(99)00594-1 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100032 ER PT J AU Afanasev, A Carlson, CE Wahlquist, C AF Afanasev, A Carlson, CE Wahlquist, C TI Soft and hard contributions to hard pion photoproduction SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID POLARIZED PARTON DISTRIBUTIONS; MESON PHOTOPRODUCTION; NUCLEON; GLUON; QUARK AB Pion photoproduction at high transverse momentum supplements what can be learned in the standard probes of deep inelastic scattering and Drell-Yan processes. With polarized initial states there is sensitivity to the polarized gluon distribution, Delta g, in leading order. This contrasts to other processes mentioned, which have no leading order gluon contribution. Additionally in some kinematic regions the process occurs mainly due to pion production at short distances ("direct pion production," resulting in kinematically isolated pions), which gives sensitivity to the high-x valence quark distribution. C1 N Carolina Cent Univ, Dept Phys, Durham, NC 27707 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Coll William & Mary, Dept Phys, Nucl & Particle Theory Grp, Williamsburg, VA 23187 USA. RP Afanasev, A (reprint author), N Carolina Cent Univ, Dept Phys, Durham, NC 27707 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 305C EP 308C DI 10.1016/S0375-9474(99)00602-8 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100037 ER PT J AU Tamminga, BH Adams, T Alton, A Arroyo, CG Avvakumov, S de Barbaro, L de Barbaro, P Bazarko, AO Bernstein, RH Bodek, A Bolton, T Brau, J Buchholz, D Budd, H Bugel, L Conrad, J Drucker, RB Formaggio, JA Frey, R Goldman, J Goncharov, M Harris, DA Johnson, RA Kim, JH King, BJ Kinnel, T Koutsoliotas, S Lamm, MJ Marsh, W Mason, D McFarland, KS McNulty, C Mishra, SR Naples, D Nienaber, P Romosan, A Sakumoto, WK Schellman, H Sciulli, FJ Seligman, WG Shaevitz, MH Smith, WH Spentzouris, P Stern, EG Vakili, M Vaitaitis, A Wu, V Yang, UK Yu, J Zeller, GP Zimmerman, ED AF Tamminga, BH Adams, T Alton, A Arroyo, CG Avvakumov, S de Barbaro, L de Barbaro, P Bazarko, AO Bernstein, RH Bodek, A Bolton, T Brau, J Buchholz, D Budd, H Bugel, L Conrad, J Drucker, RB Formaggio, JA Frey, R Goldman, J Goncharov, M Harris, DA Johnson, RA Kim, JH King, BJ Kinnel, T Koutsoliotas, S Lamm, MJ Marsh, W Mason, D McFarland, KS McNulty, C Mishra, SR Naples, D Nienaber, P Romosan, A Sakumoto, WK Schellman, H Sciulli, FJ Seligman, WG Shaevitz, MH Smith, WH Spentzouris, P Stern, EG Vakili, M Vaitaitis, A Wu, V Yang, UK Yu, J Zeller, GP Zimmerman, ED TI Low-Q(2) low-x structure function analysis of CCFR data for F-2 SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID DEUTERON STRUCTURE FUNCTIONS; INELASTIC ELECTRON-SCATTERING; PARTON DISTRIBUTIONS; MUON SCATTERING; GLOBAL ANALYSIS; A-DEPENDENCE; NEUTRINO; FREEDOM; PROTON; QUARKS C1 Columbia Univ, New York, NY 10027 USA. Kansas State Univ, Manhattan, KS 66506 USA. Univ Rochester, Rochester, NY 14627 USA. Northwestern Univ, Evanston, IL 60208 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Tamminga, BH (reprint author), Columbia Univ, New York, NY 10027 USA. RI Frey, Raymond/E-2830-2016 OI Frey, Raymond/0000-0003-0341-2636 NR 29 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 344C EP 348C DI 10.1016/S0375-9474(99)00613-2 PG 5 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100047 ER PT J AU Lapikas, L Wesseling, J Wiringa, RB AF Lapikas, L Wesseling, J Wiringa, RB TI Correlations in the ground-state wave function of Li-7 SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID MONTE-CARLO CALCULATIONS; ELECTRON-SCATTERING; NUCLEI AB Experimental momentum distributions for the transitions to the ground state and first excited state of He-6 have been measured via the reaction Li-7(e, e'p)He-6. They are compared to theoretical distributions calculated with mean-field wave functions and with variational Monte Carlo (VMC) wave functions which include strong state-dependent correlations in both Li-7 and He-6. These parameter-free VMC calculations reproduce the measured data, including their normalization. This is the first successful comparison of experiment and ab initio theory for spectroscopic factors in 1p-shell nuclei. C1 NIKHEF, NL-1009 DB Amsterdam, Netherlands. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Lapikas, L (reprint author), NIKHEF, POB 41882, NL-1009 DB Amsterdam, Netherlands. NR 10 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 377C EP 380C DI 10.1016/S0375-9474(99)00621-1 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100055 ER PT J AU Hansen, JO AF Hansen, JO CA Jefferson Lab E95-001 Collaboration TI Precise measurement of the transverse asymmetry in quasielastic (3)(H)over-right-arrow((e)over-right-arrow, e ') and the neutron magnetic form factor SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID QUASI-ELASTIC SCATTERING; POLARIZED HE-3; ELECTRON-SCATTERING AB We have measured the transverse asymmetry A(T') in (3)(H) over right arrow e((e) over right arrow, e') quasielastic scattering with high statistical precision for Q(2)-values from 0.1 to 0.6 (GeV/c)(2). The data are expected to allow extraction of the neutron magnetic form factor G(M)(n) with an uncertainty similar to that of recent experiments on deuterium. Data analysis is currently in progress. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. EM ole@jlab.org NR 12 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 EI 1873-1554 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 409C EP 412C DI 10.1016/S0375-9474(99)00670-3 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100063 ER PT J AU Passchier, I van Buuren, LD Szczerba, D Alarcon, R Bauer, TS Boersma, D van den Brand, JFJ Bulten, HJ Ferro-Luzzi, M Higinbotham, DW de Jager, CW Klous, S Kolster, H Lang, J Nikolenko, D Nooren, GJ Norum, BE Poolman, HR Rachek, I Simani, MC Six, E de Vries, H Wang, K Zhou, ZL AF Passchier, I van Buuren, LD Szczerba, D Alarcon, R Bauer, TS Boersma, D van den Brand, JFJ Bulten, HJ Ferro-Luzzi, M Higinbotham, DW de Jager, CW Klous, S Kolster, H Lang, J Nikolenko, D Nooren, GJ Norum, BE Poolman, HR Rachek, I Simani, MC Six, E de Vries, H Wang, K Zhou, ZL TI The charge form factor of the Neutron from 2(H)over-right-arrow((e)over-right-arrow, e ' n)p SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID POLARIZATION; SPECTROMETER; SCATTERING; NIKHEF; RADIUS AB We report on the first measurement of spin-correlation parameters in quasifree electron scattering from vector-polarized deuterium. Polarized electrons were injected into an electron storage ring at a beam energy of 720 MeV. A Siberian snake was employed to preserve longitudinal polarization at the interaction point. Vector-polarized deuterium was produced by an atomic beam source and injected into an open-ended cylindrical cell, internal to the electron storage ring. The spin correlation parameter A(ed)(V) was measured for the reaction (2)(H) over right arrow((e) over right arrow, e'n)p at a four-momentum transfer squared of 0.21 (GeV/c)(2) from which a value for the charge form factor of the neutron was extracted. C1 NIKHEF, NL-1009 DB Amsterdam, Netherlands. Vrije Univ Amsterdam, Dept Phys & Astron, NL-1081 HV Amsterdam, Netherlands. ETH Zurich, Inst Teilchenphys, CH-8093 Zurich, Switzerland. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. Univ Utrecht, Dept Phys, NL-3508 TA Utrecht, Netherlands. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. TJNAF, Newport News, VA 23606 USA. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. RP Passchier, I (reprint author), NIKHEF, NL-1009 DB Amsterdam, Netherlands. NR 16 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 421C EP 424C DI 10.1016/S0375-9474(99)00673-9 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100066 ER PT J AU Mestayer, MD Feuerbach, R Hicks, KH Niculescu, G AF Mestayer, MD Feuerbach, R Hicks, KH Niculescu, G CA CLAS Collaborat TI Hyperon electroproduction with CLAS SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB AB We present data for the electroproduction of K+ Lambda and K+ Sigma slates at beam energies of 2.4 and 4.0 GeV. The data were taken with the CLAS spectrometer, a large-acceptance detector housed in Hall B at CEBAF. We show plots of particle mass calculated from momentum and time-of-flight as well as missing mass plots of the recoiling hyperons. We conclude by plotting event yields that demonstrate the large acceptance of the CLAS spectrometer, and briefly discuss prospects for further analysis. C1 Jefferson Lab, Newport News, VA USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Ohio Univ, Athens, OH 45701 USA. RP Mestayer, MD (reprint author), Jefferson Lab, Newport News, VA USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 432C EP 435C DI 10.1016/S0375-9474(99)00676-4 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100069 ER PT J AU Tamura, H Abe, D Ajimura, S Akikawa, H Araki, K Bhang, HC Chrien, RE Endo, T Eugenio, P Franklin, GB Fujii, Y Fukuda, T Gan, L Hashimoto, O Hotchi, H Imai, K Kakiguchi, Y Khaustov, P Kim, JH Kim, YD Kohri, H May, M Miyoshi, T Murakami, T Nagae, T Nakano, J Noumi, H Outa, H Ozawa, K Pile, PH Quinn, BP Rusek, A Saito, T Sasao, J Sato, Y Satoh, S Sawafta, RI Schumacher, RA Sekimoto, M Takahashi, T Tamagawa, T Tang, L Tanida, K Xia, HH Yuan, L Zhou, SH Zhu, LH Zhu, XF AF Tamura, H Abe, D Ajimura, S Akikawa, H Araki, K Bhang, HC Chrien, RE Endo, T Eugenio, P Franklin, GB Fujii, Y Fukuda, T Gan, L Hashimoto, O Hotchi, H Imai, K Kakiguchi, Y Khaustov, P Kim, JH Kim, YD Kohri, H May, M Miyoshi, T Murakami, T Nagae, T Nakano, J Noumi, H Outa, H Ozawa, K Pile, PH Quinn, BP Rusek, A Saito, T Sasao, J Sato, Y Satoh, S Sawafta, RI Schumacher, RA Sekimoto, M Takahashi, T Tamagawa, T Tang, L Tanida, K Xia, HH Yuan, L Zhou, SH Zhu, LH Zhu, XF TI High-resolution hypernuclear gamma-ray spectroscopy SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID SPIN AB We have started a series of experiments of hypernuclear gamma-ray spectroscopy using a germanium detector system called Hyperball. In KEK E419, we observed two gamma transitions in Li-7(Lambda), the spin-flip M1(3/2(+) --> 1/2(+)) at 689+/-4 keV and the E2(5/2(+) --> 1/2(+)) at 2050+/-2 keV (preliminary), where B(E2) was measured to be 4.1+/-0.6+/-0.5 e(2)fm(4) (preliminary). In BNL E930, we observed the E2(5/2(+), 3/2(+) --> 1/2(+)) transitions of Be-9(Lambda) at around 3.05 MeV. C1 Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. Osaka Univ, Dept Phys, Toyonaka, Osaka 5600043, Japan. Kyoto Univ, Dept Phys, Kyoto 6068502, Japan. Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. Brookhaven Natl Lab, Upton, NY 11973 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. KEK, Inst Nucl & Particle Phys, Tsukuba, Ibaraki 3050801, Japan. Hampton Univ, Dept Phys, Hampton, VA 23668 USA. Univ Tokyo, Dept Phys, Tokyo 1130033, Japan. Sejong Univ, Dept Phys, Seoul 143747, South Korea. Tohoku Univ, Nucl Sci Lab, Sendai, Miyagi 9800826, Japan. N Carolina Agr & Technol State Univ, Dept Phys, Greensboro, NC 27411 USA. CIAE, Dept Nucl Phys, Beijing 102413, Peoples R China. RP Tamura, H (reprint author), Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. RI Zhu, Xiaofeng/B-9493-2011; Schumacher, Reinhard/K-6455-2013; Fujii, Yu/D-3413-2015 OI Schumacher, Reinhard/0000-0002-3860-1827; Fujii, Yu/0000-0001-6625-2241 NR 7 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 481C EP 484C DI 10.1016/S0375-9474(99)00636-3 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100081 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 Production of doubly-strange systems in the (K-,K+) reaction in E885 at BNL SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID H DIBARYON; HYPERNUCLEUS AB The E885 collaboration utilized the 1.8 GeV/c K- beam line at the AGS to accumulate greater than 10 times the world's existing data sample of (K-,K+) events on carbon. The data were used to search for signatures of the production of Xi hypernuclei, double-Lambda hypernuclei, and H Dibaryons. Evidence for the creation of Be-12(Xi) is seen. Reasonable agreement between the data and theory is achieved by assuming a Xi-nucleus Wood-Saxon potential well depth, V-0 Xi, of about 14 MeV. Upper limits for the production of double-Lambda hypernuclei are presented. Upper limits for H-Dibaryon production are presented which are a factor of 50 below calculated rates. 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, Neyagawa, 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 OI Schumacher, Reinhard/0000-0002-3860-1827 NR 9 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 485C EP 488C DI 10.1016/S0375-9474(99)00637-5 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100082 ER PT J AU Page, PR AF Page, PR TI Gluonic excitations' millennial finale SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID B-DECAYS; MESONS; RESONANCE; GLUEBALL AB We provide an overview of theoretical developments on hybrid mesons and glueballs in the last year at this turn of the millenium conference. Cracks in potential models of conventional mesons are developing. Hybrid meson adiabatic surfaces have been calculated and interpreted, experimental J(PC) exotics have hybrid meson, four-quark state or nonresonant interpretations, and the strong decay mechanism of hybrids has been studied. All theoretical progress on hybrid mesons in the last year is mentioned. Overall features of glueballs are visited: decays and the successes of the large N-c limit. Two promising experimental areas are mentioned: charmonium hybrids at B-factories and ss hybrids at Jefferson Lab. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Page, PR (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS-B283,POB 1663, Los Alamos, NM 87545 USA. RI Page, Philip/L-1885-2015 OI Page, Philip/0000-0002-2201-6703 NR 47 TC 3 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 585C EP 591C DI 10.1016/S0375-9474(99)00661-2 PG 7 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100106 ER PT J AU Manak, JJ Burkert, V Klein, F Mecking, B Coleman, A Funsten, H AF Manak, JJ Burkert, V Klein, F Mecking, B Coleman, A Funsten, H CA CLAS Collaboration TI Electro- and photoproduction of w(783) mesons using CLAS at Jefferson Lab SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB AB Electro- and photoproduction of omega(783) from a proton target have been measured in the CLAS detector at the Thomas Jefferson National Accelerator Facility in Newport News VA. The photoproduction data were taken over a photon energy range from 0.5 to 2.3 GeV, while the electroproduction data was obtained over a W range of 1.8-2.5 GeV/c(2). Preliminary acceptance corrected center-of-mass angular distributions have been examined for both data sets. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA USA. Coll William & Mary, Williamsburg, VA USA. RP Manak, JJ (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA USA. NR 0 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 671C EP 674C DI 10.1016/S0375-9474(99)00713-7 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100126 ER PT J AU Wagenbrunn, RF Glozman, LY Plessas, W Varga, K AF Wagenbrunn, RF Glozman, LY Plessas, W Varga, K TI Extended Goldstone-boson-exchange constituent quark model SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB C1 Univ Pavia, Dipartimento Fis Nucl & Teor, I-27100 Pavia, Italy. KEK, Tanashi Branch, Tanashi, Tokyo 1888501, Japan. Graz Univ, Inst Theoret Phys, A-8010 Graz, Austria. Argonne Natl Lab, Div Phys, Argonne, IL 60438 USA. Hungarian Acad Sci, Inst Nucl Res, H-4001 Debrecen, Hungary. RP Wagenbrunn, RF (reprint author), Univ Pavia, Dipartimento Fis Nucl & Teor, Via Bassi 6, I-27100 Pavia, Italy. RI Varga, Kalman/A-7102-2013 NR 8 TC 20 Z9 20 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 703C EP 706C DI 10.1016/S0375-9474(99)00726-5 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100134 ER PT J AU Zschiesche, D Papazoglou, P Beckmann, CW Schramm, S Schaffner-Bielich, J Stocker, H Greiner, W AF Zschiesche, D Papazoglou, P Beckmann, CW Schramm, S Schaffner-Bielich, J Stocker, H Greiner, W TI Chiral model for dense, hot and strange hadronic matter SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID FINITE NUCLEI C1 Univ Frankfurt, Inst Theoret Phys, D-60054 Frankfurt, Germany. GSI Darmstadt, D-64220 Darmstadt, Germany. Brookhaven Natl Lab, BNL Res Ctr, RIKEN, Upton, NY 11973 USA. RP Zschiesche, D (reprint author), Univ Frankfurt, Inst Theoret Phys, Robert Mayer Str 8, D-60054 Frankfurt, Germany. RI Stoecker, Horst/D-6173-2013 OI Stoecker, Horst/0000-0002-3282-3664 NR 8 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 737C EP 740C DI 10.1016/S0375-9474(99)00707-1 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100142 ER PT J AU Tribble, RE Beddo, ME Brown, CN Carey, TA Chang, TH Cooper, WE Gagliardi, CA Garvey, GT Geesaman, DF Hawker, EA He, XC Isenhower, LD Kaufman, SB Kaplan, DM Koetke, DD Lee, WM Leitch, MJ McGaughey, PL Moss, JM Mueller, BA Papavassiliou, V Peng, JC Petitt, G Reimer, PE Sadler, ME Stankus, PW Sondheim, WE Towell, RS Vasiliev, MA Webb, JC Willis, JL Young, GR AF Tribble, RE Beddo, ME Brown, CN Carey, TA Chang, TH Cooper, WE Gagliardi, CA Garvey, GT Geesaman, DF Hawker, EA He, XC Isenhower, LD Kaufman, SB Kaplan, DM Koetke, DD Lee, WM Leitch, MJ McGaughey, PL Moss, JM Mueller, BA Papavassiliou, V Peng, JC Petitt, G Reimer, PE Sadler, ME Stankus, PW Sondheim, WE Towell, RS Vasiliev, MA Webb, JC Willis, JL Young, GR CA FNAL E866 NuSea Collaboration TI Nuclear dependence of Drell-Yan and J/psi production in FNAL E866 SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID ENERGY-LOSS; 800 GEV/C; COLLISIONS; PARTONS C1 Texas A&M Univ, College Stn, TX 77843 USA. Abilene Christian Univ, Abilene, TX 79699 USA. Georgia State Univ, Atlanta, GA 30303 USA. IIT, Chicago, IL 60616 USA. LANL, Los Alamos, NM USA. New Mexico State Univ, Las Cruces, NM 88003 USA. ORNL, Oak Ridge, TN USA. Valparaiso Univ, Valparaiso, IN 46383 USA. RP Texas A&M Univ, College Stn, TX 77843 USA. EM tribble@comp.tamu.edu; cggroup@comp.tamu.edu; dbkaplan@phys.washington.edu RI Reimer, Paul/E-2223-2013 NR 16 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 EI 1873-1554 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 761C EP 764C DI 10.1016/S0375-9474(99)00715-0 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100148 ER PT J AU Kammel, P Adamczak, A Andreev, VA Balin, DV Case, T Crowe, K Deutsch, J Dick, PU Dijksman, A Egger, J Fetisov, AA Ganzha, VA Govaerts, J Hartmann, FJ Herold, WD Jatsoura, VI Krivshich, AG Maev, EM Maev, OE Markushin, V Martino, J Petitjean, C Petrov, GE Prieels, R Sadetsky, S Schapkin, G Schmidt, R Schops, W Schott, W Semenchuk, GG von Egidy, T Vorobyov, AA Voropaev, NI AF Kammel, P Adamczak, A Andreev, VA Balin, DV Case, T Crowe, K Deutsch, J Dick, PU Dijksman, A Egger, J Fetisov, AA Ganzha, VA Govaerts, J Hartmann, FJ Herold, WD Jatsoura, VI Krivshich, AG Maev, EM Maev, OE Markushin, V Martino, J Petitjean, C Petrov, GE Prieels, R Sadetsky, S Schapkin, G Schmidt, R Schops, W Schott, W Semenchuk, GG von Egidy, T Vorobyov, AA Voropaev, NI TI Precision measurement of mu p capture in a hydrogen TPC SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB AB We plan to measure the rate of the electroweak charged-current reaction mu(-) + p --> n + nu(u), with 1% precision using a new experimental technique based on a high pressure time projection chamber filled with ultrapure hydrogen gas [1]. The capture rate is sensitive to the weak form factors of the nucleon, in particular to the induced pseudoscalar coupling constant g(P) which will be measured with similar to 6% accuracy. C1 UCB, Berkeley, CA 94720 USA. LBNL, Berkeley, CA USA. PNPI, Gatchina, Russia. PSI Villigen, Villigen, Switzerland. UCL, Louvain, Belgium. CENS, Gif Sur Yvette, France. TUM, Garching, Germany. INP, Krakow, Poland. RP Kammel, P (reprint author), UCB, Berkeley, CA 94720 USA. NR 11 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 911C EP 914C DI 10.1016/S0375-9474(99)00795-2 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100183 ER PT J AU Ugolini, DW AF Ugolini, DW TI Rare decays of the eta and eta ' at CLEO II SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB AB We have searched for rare decays of the eta and eta' in hadronic events at the CLEO II detector. These decays could reveal evidence of C violation, lepton family violation, or the existence of leptoquarks. The search utilizes 4.80 fb(-1) of data collected at or just below the Y(4S) resonance. We found no statistically significant signals, and assign 90% confidence level upper limits on their branching fractions: B(eta --> e(+)e(-)) < 7.7 x 10(-5) B(eta' --> e(+)e(-)eta) < 2.4 x 10(-3) B(eta' --> e(+)e(-) pi(0)) < 1.4 x 10(-3), B(eta' --> e(+)e(-)gamma) < 0.9 x 10(-3) and B(eta' --> e mu) < 4.7 x 10(-4). C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Ugolini, DW (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Stanford, CA 94309 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 935C EP 938C DI 10.1016/S0375-9474(99)00801-5 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100189 ER PT J AU Ingelman, G Edin, A Enberg, R Rathsman, J Timneanu, N AF Ingelman, G Edin, A Enberg, R Rathsman, J Timneanu, N TI Soft colour interactions in non-perturbative QCD SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB ID FERMILAB TEVATRON; SCATTERING C1 Univ Uppsala, Dept Radiat Sci, S-75121 Uppsala, Sweden. DESY, D-22603 Hamburg, Germany. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Ingelman, G (reprint author), Univ Uppsala, Dept Radiat Sci, Box 535, S-75121 Uppsala, Sweden. RI Timneanu, Nicusor/C-7691-2012 OI Timneanu, Nicusor/0000-0001-7328-0400 NR 13 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 1007C EP 1010C DI 10.1016/S0375-9474(99)00755-1 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100207 ER PT J AU Brooks, W AF Brooks, W CA CLAS Colloboration TI CLAS - A large acceptance spectrometer for intermediate energy electromagnetic nuclear physics SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB AB The CEBAF Large Acceptance Spectrometer (CLAS) has been operating for nuclear physics experiments since December 1997. A description of its individual components and their specifications is given, followed by a description of the overall spectrometer performance and a summary of the types of physics data which have been taken to date. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Brooks, W (reprint author), Thomas Jefferson Natl Accelerator Facil, 12000 Jefferson Ave, Newport News, VA 23606 USA. RI Brooks, William/C-8636-2013 OI Brooks, William/0000-0001-6161-3570 NR 0 TC 12 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 1077C EP 1080C DI 10.1016/S0375-9474(99)00774-5 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100224 ER PT J AU Guryn, W AF Guryn, W CA pp2pp R7 Collaboration TI Total and differential cross sections and polarization effects in proton-proton elastic scattering at RHIC SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT 15th International Conference on Particles and Nuclei CY JUN 10-16, 1999 CL UPPSALA, SWEDEN SP Dept Radiat Sci, Svedberg Lab, Int Union Pure & Appl Phys, European Phys Soc, Int Ctr Theoret Phys, Swedish Royal Acad Sci, Nobel Comm, Swedish Nat Sci Res Council, Swedish Inst, Wenner Gren Fdn, Uppsala Univ, Fac Sci & Technol, City Uppsala, SAAB Automobile AB AB The physics program, the setup, and the performance of an experiment to measure elastic scattering of polarized protons at the Relativistic Heavy Ion Collider (RHIC) are described. In the medium t range, diffractive region, with four momenta transferred 0.006 < -t < 1.5(GeV/c)(2), the experiment will address one of the main, unsolved problems in particle and nuclear physics: long-range QCD and confinement. In the small t range, Coulomb Nuclear Interference (CNI), 0.0004 < -t < 0.12(GeV/c)(2), the experiment will, in a model-independent way, test general analytical properties of scattering amplitudes: analyticity, unitarity, and crossing symmetry. In addition, by measuring single spin asymmetries such as AN, double spin correlation parameter ANN, and cross section difference Delta(sigma T) = sigma(tot)(up arrow,down arrow) - sigma tot(up arrow, up arrow), we will be able to determine the helicity amplitudes phi(i) Those amplitudes are not well known at this time, so their systematic study at RHIC will help understand spin structure of nucleon and the exchanged mediator of the force, Pomeron and Odderon. A polarized gas jet target added to the setup will expand the physics capabilities to cover the fixed-target range of energies, giving centre of mass (cms) energy range 7 < root s < 500GeV. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Guryn, W (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 31 PY 2000 VL 663 BP 1115C EP 1118C DI 10.1016/S0375-9474(99)00563-1 PG 4 WC Physics, Nuclear SC Physics GA 294PT UT WOS:000085920100233 ER PT J AU Del Duca, V Kilgore, WB Maltoni, F AF Del Duca, V Kilgore, WB Maltoni, F TI Multi-photon amplitudes for next-to-leading order QCD SO NUCLEAR PHYSICS B LA English DT Article ID ONE-LOOP CORRECTIONS; GAUGE-THEORIES; HIGGS-BOSON; GLUON SCATTERING; COLLIDERS AB We present the tree-level amplitudes involving one, two and three photons that are required for next-to-leading order QCD calculations of production rates of three final-state particles, We also present the required one-loop amplitudes in terms of previously published results. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Ist Nazl Fis Nucl, Sez Torino, I-10125 Turin, Italy. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Turin, Dipartimento Fis Teor, I-10125 Turin, Italy. RP Del Duca, V (reprint author), Ist Nazl Fis Nucl, Sez Torino, Via P Giuria 1, I-10125 Turin, Italy. RI del duca, vittorio/F-6992-2012 NR 38 TC 11 Z9 11 U1 0 U2 0 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 JAN 31 PY 2000 VL 566 IS 1-2 BP 252 EP 274 DI 10.1016/S0550-3213(99)00663-X PG 23 WC Physics, Particles & Fields SC Physics GA 285XY UT WOS:000085414700009 ER PT J AU Dalvit, DAR Neto, PAM AF Dalvit, DAR Neto, PAM TI Decoherence via the dynamical Casimir effect SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUANTUM BROWNIAN-MOTION; DISPERSIVE MIRROR; WAVE PACKET; RADIATION; ELECTRODYNAMICS; FLUCTUATIONS; REDUCTION; CAVITY; VACUUM; MASS AB We derive a master equation for a mirror interacting with the vacuum field via radiation pressure. The dynamical Casimir effect leads to decoherence of a superposition state in a time scale that depends on the degree of "macroscopicity" of the state components, and which may he much shorter than the relaxation time scale. Coherent states are selected by the interaction as pointer states. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. UFRJ, Inst Fis, BR-21945970 Rio De Janeiro, Brazil. RP Dalvit, DAR (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-6,MS B288, Los Alamos, NM 87545 USA. NR 18 TC 32 Z9 33 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 JAN 31 PY 2000 VL 84 IS 5 BP 798 EP 801 DI 10.1103/PhysRevLett.84.798 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700002 ER PT J AU Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Wolf, A Wu, J Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, TK Briere, RA Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H AF Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Wolf, A Wu, J Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, TK Briere, RA Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H CA CLEO Collaboration TI Observation of radiative leptonic decay of the tau lepton SO PHYSICAL REVIEW LETTERS LA English DT Article ID MONTE-CARLO; BRANCHING FRACTION; LORENTZ STRUCTURE; WEAK INTERACTION; LIBRARY AB Using 4.68 fb(-1) of e(+) e(-) annihilation data collected with the CLEO II detector at the Cornell Electron Storage Ring, we have studied tau radiative decays tau(-) --> nu(tau)mu(-)<<(nu)over bar>(mu)gamma and tau- --> nu(tau)e(-)<(nu)over bar>(e)gamma. For a 10 MeV minimum photon energy in the tau rest frame, the branching fraction for radiative tau decay to a muon or electron is measured to be (3.61 +/- 0.16 +/- 0.35) x 10(-3) or (1.75 +/- 0.06 +/- 0.17) x 10(-2), respectively. The branching fractions are in agreement with standard model theoretical predictions. C1 Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Ottawa, ON, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Univ Texas, Edinburg, TX 78539 USA. Yonsei Univ, Seoul 120749, South Korea. Univ Cincinnati, Cincinnati, OH 45221 USA. RP Bergfeld, T (reprint author), Univ Illinois, Urbana, IL 61801 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014; OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039; Bean, Alice/0000-0001-5967-8674 NR 22 TC 8 Z9 9 U1 1 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 JAN 31 PY 2000 VL 84 IS 5 BP 830 EP 834 DI 10.1103/PhysRevLett.84.830 PG 5 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700010 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D 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 Busk, BS Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C 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 Chang, PS Chang, PT 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 Cobal, M Cocca, E 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 Gadomski, S 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 Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M 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, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K 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 Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M 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 Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K 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 Takashima, R Takikawa, K Tanaka, M Takano, T 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 Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, 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 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 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 Busk, BS Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C 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 Chang, PS Chang, PT 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 Cobal, M Cocca, E 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 Gadomski, S 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 Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M 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, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K 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 Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M 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 Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K 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 Takashima, R Takikawa, K Tanaka, M Takano, T 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 Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, 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 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 Search for a fourth-generation quark more massive than the Z(0) boson in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID NEUTRAL-CURRENT DECAY; TOP-QUARK; B' QUARK; LEPTONS; MODEL; SYMMETRY; PHOTONS; TRISTAN; CHARGE; EVENTS AB We present the results of a search for pair production of a fourth-generation charge -1/3 quark (b') in root s = 1.8 TeV p (p) over bar collisions using 88 pb(-1) of data obtained with the Collider Detector at Fermilab. We assume that both quarks decay via the flavor-changing neutral current process b' --> bZ(0) and that the b' mass is greater than m(Z) + m(b). We studied the decay mode b'<(b')over bar> --> Z(0)Z(0)b (b) over bar where one Z(0) decays into e(+) e(-) or mu(+) mu(-) and the other decays hadronically, giving a signature of two leptons plus jets. An upper limit on the sigma(p (p) over bar --> b'<(b')over bar>) x [B(b' --> bZ(0))](2) is established as a function of the b' mass. We exclude at 95% confidence level a b' quark with mass between 100 and 199 GeV/c(2) for B(b' --> bZ(0)) = 100%. 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, Santander 39005, 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. High Energy Accelerator Res Org, KEK, 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, Sezione 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; vilar, rocio/D-7454-2014; Paulini, Manfred/N-7794-2014; vilar, rocio/P-8480-2014; Prokoshin, Fedor/E-2795-2012; Introzzi, Gianluca/K-2497-2015 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; Prokoshin, Fedor/0000-0001-6389-5399; Introzzi, Gianluca/0000-0002-1314-2580 NR 35 TC 26 Z9 26 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 JAN 31 PY 2000 VL 84 IS 5 BP 835 EP 840 DI 10.1103/PhysRevLett.84.835 PG 6 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700011 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M 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 Blusk, S Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C 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 Chang, PS Chang, PT 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 Cobal, M Cocca, E Connolly, A Conway, J Cooper, J Cordelli, M da Costa, JG Costanzo, D 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 Gadomski, S Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, H 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 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 Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M 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, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K 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 Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M 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 Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D 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 Takashima, R Takikawa, K Tanaka, M Takano, T 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 Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T 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 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 Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M 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 Blusk, S Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C 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 Chang, PS Chang, PT 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 Cobal, M Cocca, E Connolly, A Conway, J Cooper, J Cordelli, M da Costa, JG Costanzo, D 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 Gadomski, S Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, H 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 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 Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M 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, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K 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 Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M 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 Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D 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 Takashima, R Takikawa, K Tanaka, M Takano, T 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 Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T 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 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 Transverse momentum and total cross section of e(+)e(-) pairs in the Z-boson region from p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID QED RADIATIVE-CORRECTIONS; = 1.8 TEV; UNIVERSAL MONTE-CARLO; PARTON DISTRIBUTIONS; PBARP COLLISIONS; HADRON COLLIDERS; W-BOSONS; PHOTOS; GLUON; QCD AB The transverse momentum and total cross section of e(+)e(-) pairs in the Z-boson region of 66 < M-ee < 116 GeV/c(2) from p (p) over bar collisions at root s = 1.8 TeV are measured using 110 pb(-1) of collisions taken by the Collider Detector at Fermilab during 1992-1995. The total cross section is measured to be 248 +/- 11 pb. The differential transverse momentum cross section is compared with calculations that match quantum chromodynamics perturbation theory at high transverse momentum with the gluon resummation formalism at low transverse momentum. 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, Santander 39005, 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. High Energy Accelerator Res Org, KEK, 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 Padua, Ist Nazl Fis Nucl, Sezione 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 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; Prokoshin, Fedor/E-2795-2012; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; vilar, rocio/P-8480-2014; Introzzi, Gianluca/K-2497-2015; vilar, rocio/D-7454-2014 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Prokoshin, Fedor/0000-0001-6389-5399; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; NR 26 TC 87 Z9 87 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 31 PY 2000 VL 84 IS 5 BP 845 EP 850 DI 10.1103/PhysRevLett.84.845 PG 6 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700013 ER PT J AU Cowan, TE Hunt, AW Phillips, TW Wilks, SC Perry, MD Brown, C Fountain, W Hatchett, S Johnson, J Key, MH Parnell, T Pennington, DM Snavely, RA Takahashi, Y AF Cowan, TE Hunt, AW Phillips, TW Wilks, SC Perry, MD Brown, C Fountain, W Hatchett, S Johnson, J Key, MH Parnell, T Pennington, DM Snavely, RA Takahashi, Y TI Photonuclear fission from high energy electrons from ultraintense laser-solid interactions SO PHYSICAL REVIEW LETTERS LA English DT Article ID HOT-ELECTRONS; PLASMA; ACCELERATION; BREAKING; PULSE AB A new regime of laser-matter interactions in which the quiver motion of plasma electrons is fully relativistic, with energies extending well above the threshold for nuclear processes, is studied using a petawatt laser system. In solid target experiments with focused intensities exceeding 10(20) W/cm(2), high energy electron generation, hard bremsstrahlung, and nuclear phenomena have been observed. We report here a quantitative comparison of the high energy electrons and the bremsstrahlung spectrum, as measured by photonuclear reaction yields, including the photoinduced fission of U-238. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Alabama, Huntsville, AL 35899 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Univ Space Res Assoc, Huntsville, AL 35806 USA. Harvard Univ, Cambridge, MA 02138 USA. RP Cowan, TE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Cowan, Thomas/A-8713-2011 OI Cowan, Thomas/0000-0002-5845-000X NR 26 TC 193 Z9 201 U1 0 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 31 PY 2000 VL 84 IS 5 BP 903 EP 906 DI 10.1103/PhysRevLett.84.903 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700027 ER PT J AU Simkin, MV Mahan, GD AF Simkin, MV Mahan, GD TI Minimum thermal conductivity of superlattices SO PHYSICAL REVIEW LETTERS LA English DT Article ID TRANSPORT AB The phonon thermal conductivity of a multilayer is calculated for transport perpendicular to the layers. There is a crossover between particle transport for thick layers to wave transport for thin layers. The calculations show that the conductivity has a minimum value for a layer thickness somewhat smaller then the mean free path of the phonons. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Simkin, MV (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. NR 19 TC 280 Z9 284 U1 9 U2 50 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 JAN 31 PY 2000 VL 84 IS 5 BP 927 EP 930 DI 10.1103/PhysRevLett.84.927 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700033 ER PT J AU Xu, SH Keeffe, M Yang, Y Chen, C Yu, M Lapeyre, GJ Rotenberg, E Denlinger, J Yates, JT AF Xu, SH Keeffe, M Yang, Y Chen, C Yu, M Lapeyre, GJ Rotenberg, E Denlinger, J Yates, JT TI Photoelectron diffraction imaging for C2H2 and C2H4 chemisorbed on Si(100) reveals a new bonding configuration SO PHYSICAL REVIEW LETTERS LA English DT Article ID ADSORPTION; ACETYLENE; DECOMPOSITION; SI(001) AB A new adsorption site for adsorbed acetylene on Si(100) is observed by photoelectron imaging based on the holographic principle. The diffraction effects in the carbon Is angle-resolved photoemission are inverted (including the small-cone method) to obtain an image of the atom's neighboring carbon. The chemisorbed acetylene molecule is bonded to four silicon surface atoms. In contrast to the C2H2 case, the image for adsorbed C2H4 shows it bonded to two Si surface atoms. C1 Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. LBNL, Adv Light Source, Berkeley, CA 94720 USA. Univ Pittsburgh, Ctr Surface Sci, Dept Chem, Pittsburgh, PA 15260 USA. Univ Pittsburgh, Ctr Surface Sci, Dept Phys, Pittsburgh, PA 15260 USA. RP Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. RI Rotenberg, Eli/B-3700-2009 OI Rotenberg, Eli/0000-0002-3979-8844 NR 14 TC 72 Z9 72 U1 1 U2 6 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 JAN 31 PY 2000 VL 84 IS 5 BP 939 EP 942 DI 10.1103/PhysRevLett.84.939 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700036 ER PT J AU Buczko, R Pennycook, SJ Pantelides, ST AF Buczko, R Pennycook, SJ Pantelides, ST TI Bonding arrangements at the Si-SiO2 and SiC-SiO2 interfaces and a possible origin of their contrasting properties SO PHYSICAL REVIEW LETTERS LA English DT Article ID CORE-LEVEL SHIFTS; SI(001)-SIO2 INTERFACE; MOLECULAR-DYNAMICS; SI/SIO2 INTERFACE; FIRST-PRINCIPLES; OXYGEN; ADSORPTION; SILICON; TRANSFORMATION; SURFACES AB We report ab initio calculations designed to explore the relative energetics of different interface bonding structures. We find that, for Si (001), abrupt (no suboxide layer) interfaces generally have lower energy because of the surface geometry and the softness of the Si-O-Si angle. However, two energetically degenerate phases are possible at the nominal interface layer, so that a mix of the two is the likely source of the observed suboxide and dangling bonds. In principle, these effects may be avoidable by low-temperature deposition. In contrast, the topology and geometry of SiC surfaces is not suitable for abrupt interfaces. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RP Buczko, R (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 22 TC 159 Z9 161 U1 0 U2 29 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 JAN 31 PY 2000 VL 84 IS 5 BP 943 EP 946 DI 10.1103/PhysRevLett.84.943 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700037 ER PT J AU Stach, EA Schwarz, KW Hull, R Ross, FM Tromp, RM AF Stach, EA Schwarz, KW Hull, R Ross, FM Tromp, RM TI New mechanism for dislocation blocking in strained layer epitaxial growth SO PHYSICAL REVIEW LETTERS LA English DT Article ID THREADING DISLOCATION; RELAXATION; HETEROSTRUCTURES; SURFACE; GLIDE; SI AB Dislocation interactions play a critical role in plasticity and heteroepitaxial strain relaxation. We use real time transmission electron microscopy observations of the interaction between threading and misfit dislocations in SiGe heterostructures to investigate interactions quantitatively. In addition to the expected long-range blocking of threading segments, we observe a new short-range mechanism which is significantly more effective. Simulations show that this reactive blocking occurs when two dislocations with the same Burgers vector reconnect. C1 LBNL, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. IBM Corp, Div Res, TJ Watson Res Ctr, Yorktown Heights, NY 10598 USA. Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22903 USA. RP Stach, EA (reprint author), LBNL, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RI Stach, Eric/D-8545-2011 OI Stach, Eric/0000-0002-3366-2153 NR 20 TC 32 Z9 32 U1 0 U2 17 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 JAN 31 PY 2000 VL 84 IS 5 BP 947 EP 950 DI 10.1103/PhysRevLett.84.947 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700038 ER PT J AU Liu, DJ Evans, JW AF Liu, DJ Evans, JW TI Symmetry-breaking and percolation transitions in a surface reaction model with superlattice ordering SO PHYSICAL REVIEW LETTERS LA English DT Article ID SQUARE LATTICE-GAS; PHASE-TRANSITIONS; ADSORPTION; DIFFUSION; KINETICS AB A symmetry-breaking order-disorder transition of the Ising type is found in a nonequilibrium surface reaction model for CO oxidation incorporating superlattice ordering of adsorbed oxygen. We relate this transition to the percolation of superlattice domains of oxygen, and discuss the consequences for chemical diffusion of coadsorbed CO. The latter constitutes a new type of problem involving transport in disordered media. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Math, Ames, IA 50011 USA. RP Liu, DJ (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 19 TC 41 Z9 41 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 JAN 31 PY 2000 VL 84 IS 5 BP 955 EP 958 DI 10.1103/PhysRevLett.84.955 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700040 ER PT J AU Zhang, SB Branz, HM AF Zhang, SB Branz, HM TI Nonradiative electron-hole recombination by a low-barrier pathway in hydrogenated silicon semiconductors SO PHYSICAL REVIEW LETTERS LA English DT Article ID AMORPHOUS-SILICON; SI-H; DISSOCIATION AB A microscopic pathway for nonradiative electron-hole recombination by large structural reconfiguration in hydrogenated Si is found with first-principles calculations. Trapped-biexciton formation leads to a low-barrier reconfiguration of the H atom, accompanied by crossing of doubly occupied electron and hole levels in the band gap. This crossing represents the nonradiative recombination of the carriers, without multiphonon emission. The proposal provides a mechanism for carrier-induced H emission during metastable degradation of hydrogenated amorphous silicon. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Krausnick, Jennifer/D-6291-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 27 TC 20 Z9 20 U1 0 U2 2 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 JAN 31 PY 2000 VL 84 IS 5 BP 967 EP 970 DI 10.1103/PhysRevLett.84.967 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700043 ER PT J AU Di Ventra, M Pantelides, ST Lang, ND AF Di Ventra, M Pantelides, ST Lang, ND TI First-principles calculation of transport properties of a molecular device SO PHYSICAL REVIEW LETTERS LA English DT Article ID CARBON NANOTUBES; SINGLE-WALL; WIRES; CONDUCTANCE; ATOM AB We report first-principles calculations of the current-voltage (I-V) characteristics of a molecular device and compare with experiment. We find that the shape of the I-V curve is largely determined by the electronic structure of the molecule, while the presence of single atoms at the molecule-electrode interface play a key role in determining the absolute value of the current. The results show that such simulations would be useful for the design of future microelectronic devices for which the Boltzman-equation approach is no longer applicable. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. IBM Corp, Thomas J Watson Res Ctr, Div Res, Yorktown Hts, NY 10598 USA. RP Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RI Di Ventra, Massimiliano/E-1667-2011 OI Di Ventra, Massimiliano/0000-0001-9416-189X NR 22 TC 736 Z9 736 U1 12 U2 93 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 JAN 31 PY 2000 VL 84 IS 5 BP 979 EP 982 DI 10.1103/PhysRevLett.84.979 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700046 ER PT J AU Rohlsberger, R Toellner, TS Sturhahn, W Quast, KW Alp, EE Bernhard, A Burkel, E Leupold, O Gerdau, E AF Rohlsberger, R Toellner, TS Sturhahn, W Quast, KW Alp, EE Bernhard, A Burkel, E Leupold, O Gerdau, E TI Coherent resonant X-ray scattering from a rotating medium SO PHYSICAL REVIEW LETTERS LA English DT Article ID SYNCHROTRON-RADIATION; SPECTROSCOPY; SHIFT AB A coherently excited nuclear state in a rotating sample acquires a phase shift during its time evolution that is proportional to its angular momentum and the rotation angle. As a consequence, the radiative decay of the excited state proceeds into the rotated direction, and the time spectrum of the nuclear decay is mapped onto an angular scale. This effect has been observed in nuclear resonant scattering of synchrotron radiation from a Fe-57 metal foil rotating at 18 kHz. C1 Univ Rostock, Fachbereich Phys, D-18055 Rostock, Germany. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ Hamburg, Inst Expt Phys 2, D-22761 Hamburg, Germany. RP Rohlsberger, R (reprint author), Univ Rostock, Fachbereich Phys, August Bebel Str 55, D-18055 Rostock, Germany. RI Rohlsberger, Ralf/J-4173-2013 OI Rohlsberger, Ralf/0000-0001-6005-5183 NR 20 TC 32 Z9 32 U1 2 U2 5 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 JAN 31 PY 2000 VL 84 IS 5 BP 1007 EP 1010 DI 10.1103/PhysRevLett.84.1007 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700053 PM 11017427 ER PT J AU Dunn, JH Arvanitis, D Carr, R Martensson, N AF Dunn, JH Arvanitis, D Carr, R Martensson, N TI Influence of source coherence on X-ray absorption spectroscopy SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIFFRACTION; UNDULATOR; SPECKLE AB Core-level x-ray absorption spectroscopy measurements have bean performed at the L-3,L-2 edges of Fe and Co thin films. The degree of source coherence was varied using soft x rays from five different beam lines. We observe an increase of the L edge resonance intensities relative to the continuum states which we propose is due to the presence of transverse coherence in the exciting radiation. C1 Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Dunn, JH (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NR 21 TC 9 Z9 9 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 31 PY 2000 VL 84 IS 5 BP 1031 EP 1034 DI 10.1103/PhysRevLett.84.1031 PG 4 WC Physics, Multidisciplinary SC Physics GA 278TU UT WOS:000085005700059 PM 11017433 ER PT J AU Gabitov, I Schafer, T Turitsyn, SK AF Gabitov, I Schafer, T Turitsyn, SK TI Lie-transform averaging in nonlinear optical transmission systems with strong and rapid periodic dispersion variations SO PHYSICS LETTERS A LA English DT Article ID ENHANCED-POWER SOLITONS; GUIDING-CENTER SOLITON; PULSE DYNAMICS; FIBERS; MANAGEMENT; COMMUNICATION; COMPENSATION AB Using Lie-transform techniques, we derive higher-order corrections to the path-averaged model governing evolution of dispersion-managed solitons in the spectral domain. The result holds in the case of arbitrary (including moderate and strong) dispersion. The general theory is illustrated by deriving the exact formulas + for a specific symmetric dispersion map. (C) 2,000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Dusseldorf, Inst Theoret Phys 1, D-40225 Dusseldorf, Germany. Aston Univ, Div Elect Eng & Comp Sci, Birmingham B4 7ET, W Midlands, England. RP Gabitov, I (reprint author), Univ Calif Los Alamos Natl Lab, MS-B284, Los Alamos, NM 87545 USA. RI Turitsyn, Sergei/J-5562-2013 OI Turitsyn, Sergei/0000-0003-0101-3834 NR 26 TC 12 Z9 12 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD JAN 31 PY 2000 VL 265 IS 4 BP 274 EP 281 DI 10.1016/S0375-9601(99)00901-9 PG 8 WC Physics, Multidisciplinary SC Physics GA 281VY UT WOS:000085183200006 ER PT J AU Liaw, PK Wang, H Jiang, L Yang, B Huang, JY Kuo, RC Huang, JG AF Liaw, PK Wang, H Jiang, L Yang, B Huang, JY Kuo, RC Huang, JG TI Thermographic detection of fatigue damage of pressure vessel steels at 1,000 Hz and 20 Hz SO SCRIPTA MATERIALIA LA English DT Article DE fatigue; nondestructive evaluation; thermography; infrared (IR) spectroscopy; martensite C1 Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Inst Nucl Energy Res, Lungtan 325, Taiwan. Taiwan Power Co, Taipei, Taiwan. RP Liaw, PK (reprint author), Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. RI Wang, Hsin/A-1942-2013 OI Wang, Hsin/0000-0003-2426-9867 NR 17 TC 93 Z9 97 U1 0 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JAN 31 PY 2000 VL 42 IS 4 BP 389 EP 395 DI 10.1016/S1359-6462(99)00358-9 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 286FA UT WOS:000085431900012 ER PT J AU Majidi, V Xu, N Smith, RG AF Majidi, V Xu, N Smith, RG TI Electrothermal vaporization, part 1: gas phase chemistry SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Review DE vaporization mechanism; graphite surface chemistry; gas-phase reactions; sample introduction; chemical reactors ID ATOMIC-ABSORPTION SPECTROMETRY; GRAPHITE-FURNACE ATOMIZATION; GASEOUS-CARBIDE MECHANISM; PLASMA-MASS SPECTROMETRY; LASER-INDUCED PLASMAS; ETV-ICP-MS; SPIKE FORMATION; ALUMINUM-OXIDE; ION-SOURCE; CARBON AB This manuscript is the first of a two-part publication on evaluation of vaporization and atomization processes in electrothermal vaporizers (ETV). Part 1 is specifically focused on gas phase (and heterogeneous) chemistry in ETVs. Molecular absorption spectroscopy and thermogravimetric analysis (in conjunction with gas-phase mass spectrometry) are used to investigate the vaporization of Mg, Ca, Sr, Ba, Co and Ni (chloride and nitrate salts). Graphite, Pt, and Ta were used as substrate material for vaporizers to elucidate some observations of gas-phase chemistry. The experiments in Part I and II of this series are intentionally performed using wall vaporization to closely mimic the conditions used when ETV is employed as a sample introduction device. Published by Elsevier Science B.V. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. ManTech Environm Res Serv Corp, Ada, OK 74821 USA. Lexmark Int Dept E05A, Lexington, KY 40550 USA. RP Majidi, V (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, CST-9,MS K484, Los Alamos, NM 87545 USA. NR 74 TC 25 Z9 26 U1 2 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0584-8547 J9 SPECTROCHIM ACTA B JI Spectroc. Acta Pt. B-Atom. Spectr. PD JAN 31 PY 2000 VL 55 IS 1 BP 3 EP 35 DI 10.1016/S0584-8547(99)00163-9 PG 33 WC Spectroscopy SC Spectroscopy GA 290DC UT WOS:000085660100001 ER PT J AU Downing, DJ Fedorov, VV Lawkins, WF Morris, MD Ostrouchov, G AF Downing, DJ Fedorov, VV Lawkins, WF Morris, MD Ostrouchov, G TI Large data series: modeling the usual to identify the unusual SO COMPUTATIONAL STATISTICS & DATA ANALYSIS LA English DT Article DE local models; nonlinear dynamical model; segmentation; data reduction; feature extraction; principal components AB "Standard" approaches, such as regression analysis, Fourier analysis, Box-Jenkins procedure, etc., that handle a data series as a whole are not useful for very large data sets for at least two reasons. First, even with computer hardware available today, including parallel processors and storage devices, there are no effective means for manipulating and analyzing gigabyte, or larger, data files. Second, in general it cannot be assumed that a very large data set is "stable" by the usual measures, like homogeneity, stationarity, and ergodicity that standard analysis techniques require. Both reasons suggest to segment the data and use "local" data analysis on each segment. The results of these local analyses can then be analyzed globally. We use local regression models within segments and show that analysis of optimal local regression models is operationally identical to a nonlinear dynamical modeling approach. (C) 2000 Elsevier Science B.V. All rights reserved. C1 SmithKline Beecham, King Of Prussia, PA 19406 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Iowa State Univ, Dept Stat, Ames, IA 50011 USA. NR 12 TC 9 Z9 9 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9473 J9 COMPUT STAT DATA AN JI Comput. Stat. Data Anal. PD JAN 28 PY 2000 VL 32 IS 3-4 BP 245 EP 258 DI 10.1016/S0167-9473(99)00079-1 PG 14 WC Computer Science, Interdisciplinary Applications; Statistics & Probability SC Computer Science; Mathematics GA 285QJ UT WOS:000085399500003 ER PT J AU Williams, RV Colvin, ME Tran, N Warrener, RN Margetic, D AF Williams, RV Colvin, ME Tran, N Warrener, RN Margetic, D TI Exceptionally pyramidalized olefins: A theoretical study of the cyclopropenyl fused tricycles tricyclo[3.2.1.0(2,4)]oct-2(4)-ene, tricyclo[3.2.1.0(2,4)]octa-2(4),6-diene, tricyclo[3.2.2.0(2,4)]non-2(4)-ene, and tricyclo[3.2.2.0(2,4)]nona-2(4),6-diene SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID ALDER CYCLO-ADDITIONS; DOUBLE-BOND GEOMETRY; ELECTRONIC CONTROL; SYN-SESQUINORBORNATRIENE; CORRELATION-ENERGY; AB-INITIO; STEREOSELECTIVITY; ALKENES; CONSEQUENCES; NORBORNENE AB RHF, MP2, and TCSCF ab initio theory and B3LYP, B3PW91, and SVWN density functional theory were used to study the series of cyclopropenyl-fused tricycles 9-12. In each of 9-12, the cyclopropenyl double bond is exceptionally pyramidalized (butterfly angle psi similar to 41-50 degrees) with both endo and exo bent isomers. In the norbornyl systems (9 and 10), the endo bent isomers are more stable than the exo bent isomers, whereas in the bicyclo[2.2.2]octadiene 12 the reverse is true with the exo bent isomer being the low energy form. The activation barriers for the endo/exo interconversions are calculated to be relatively low (Delta H-not equal similar to 6-13 kcal/mol). C1 Univ Idaho, Dept Chem, Moscow, ID 83844 USA. Univ Calif Lawrence Livermore Natl Lab, Computat Biochem Grp, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Univ Cent Queensland, Ctr Mol Architecture, Rockhampton, Qld 4702, Australia. RP Williams, RV (reprint author), Univ Idaho, Dept Chem, Moscow, ID 83844 USA. NR 39 TC 27 Z9 27 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD JAN 28 PY 2000 VL 65 IS 2 BP 562 EP 567 DI 10.1021/jo991496+ PG 6 WC Chemistry, Organic SC Chemistry GA 276YF UT WOS:000084905400043 ER PT J AU McPherson, DW Greenbaum, M Luo, H Beets, AL Knapp, FF AF McPherson, DW Greenbaum, M Luo, H Beets, AL Knapp, FF TI Evaluation of Z-(R,R)-IQNP for the potential imaging of m2 mAChR rich regions of the brain and heart SO LIFE SCIENCES LA English DT Article DE Z-(R,R)-IQNP; radiotracer; muscarinic receptor; brain; heart ID MUSCARINIC-CHOLINERGIC RECEPTOR; EMISSION COMPUTED-TOMOGRAPHY; IODINE-125-LABELED 1-AZABICYCLO<2.2.2>OCT-3-YL ALPHA-HYDROXY-ALPHA-(1-IODO-1-PRO; ALZHEIMERS-DISEASE; 3-QUINUCLIDINYL BENZILATE; ACETYLCHOLINE-RECEPTORS; HIGH-AFFINITY; REM-SLEEP; BINDING; DEMENTIA AB Alterations in the function or density of the m2 muscarinic (mAChR) subtype have been postulated to play an important role in various dementias such as Alzheimer's disease. The ability to image and quantify the m2 mAChR subtype is of importance for a better understanding of the m2 subtype function in various dementias. Z-(R)-1-Azabicyclo[2.2.2]oct-3-y (R)-alpha-hydroxy-alpha-(1-iodo-1-propen-3 -yl)-alpha-phenylacetate (Z-(R,R)-IQNP) has demonstrated significant uptake in cerebral regions that contain a high concentration of m2 mAChR subtype in addition to heart tissue. The present study was undertaken to determine if the uptake of Z-(R,R)-IQNP in these regions is a receptor mediated process and to identify the radiospecies responsible for binding at the receptor site. A blocking study demonstrated cerebral and. cardiac levels of activity were significantly reduced by pretreatment (2-3 mg/kg) of (R)-3-quinuclidinyl benzilate, dexetimide and scopolamine, established muscarinic antagonists. A direct comparison of the cerebral and cardiac uptake of [I-125]-Z-(R,R)-IQNP and [I-131]-E-(R,R)-IQNP (high uptake in m1, m4 rich mAChR cerebral regions) demonstrated Z-(R,R)-IQNP localized to a higher degree in cerebral and cardiac regions containing a high concentration of the m2 mAChR subtype as directly compared to E-(R,R)-IQNP. In addition, a study utilizing [I-123]-Z(R,R)-IQNP, [I-131]-iododexetimide and [I-125]-R-3-quinuclidinyl S-4-iodobenzilate, Z-(R,R)-IQNP demonstrated significantly higher uptake and longer residence time in those regions which contain a high concentration of the m2 receptor subtype. Folch extraction of global brain and heart tissue at various times post injection of [I-125]-Z-(R,R)-IQNP demonstrated that approximately 80% of the activity was extracted in the lipid soluble fraction and identified as the parent ligand by TLC and HPLC analysis. These results demonstrate Z-(R,R)-IQNP has significant uptake, long residence time and high stability in cerebral and cardiac tissues containing high levels of the m2 mAChR subtype. These combined results strongly suggest that Z-(R,R)-IQNP is an attractive ligand for the in vivo imaging and evaluation of m2 rich cerebral and cardiac regions by SPECT. C1 Oak Ridge Natl Lab, Div Life Sci, Nucl Med Grp, Oak Ridge, TN 37831 USA. RP McPherson, DW (reprint author), Oak Ridge Natl Lab, Div Life Sci, Nucl Med Grp, POB 2008,Bldg 4501, Oak Ridge, TN 37831 USA. NR 43 TC 7 Z9 8 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0024-3205 J9 LIFE SCI JI Life Sci. PD JAN 28 PY 2000 VL 66 IS 10 BP 885 EP 896 DI 10.1016/S0024-3205(99)00672-4 PG 12 WC Medicine, Research & Experimental; Pharmacology & Pharmacy SC Research & Experimental Medicine; Pharmacology & Pharmacy GA 281FV UT WOS:000085148000003 PM 10714889 ER PT J AU Kende, H AF Kende, H TI E-knowledge hullabaloo - Or when will the glass spill over? SO SCIENCE LA English DT Letter C1 Michigan State Univ, US DOE, Plant Res Lab, E Lansing, MI 48824 USA. RP Kende, H (reprint author), Michigan State Univ, US DOE, Plant Res Lab, E Lansing, MI 48824 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 28 PY 2000 VL 287 IS 5453 BP 591 EP 591 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 278KR UT WOS:000084989400017 PM 10691537 ER PT J AU Heben, MJ Dillon, AC AF Heben, MJ Dillon, AC TI Room-temperature hydrogen storage in nanotubes SO SCIENCE LA English DT Letter C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Heben, MJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 2 TC 5 Z9 6 U1 0 U2 5 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 28 PY 2000 VL 287 IS 5453 BP 593 EP 593 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 278KR UT WOS:000084989400021 ER PT J AU Caldeira, K Duffy, PB AF Caldeira, K Duffy, PB TI The role of the Southern Ocean in uptake and storage of anthropogenic carbon dioxide SO SCIENCE LA English DT Article ID GENERAL-CIRCULATION MODEL; SEA-ICE FORMATION; MIXED LAYER; CO2; SENSITIVITY; SIMULATION; BUDGET; WATER; SALT AB An ocean-climate model that shows high fluxes of anthropogenic carbon dioxide into the Southern Ocean, but very Low storage of anthropogenic carbon there, agrees with observation-based estimates of ocean storage of anthropogenic carbon dioxide. This low simulated storage indicates a subordinate role for deep convection in the present-day Southern Ocean. The primary mechanism transporting anthropogenic carbon out of the Southern Ocean is isopycnal transport. These results imply that if global climate change reduces the density of surface waters in the Southern Ocean, isopycnal surfaces that now outcrop may become isolated from the atmosphere, tending to diminish Southern Ocean carbon uptake. C1 Univ Calif Lawrence Livermore Natl Lab, Climate Syst Modeling Grp, Livermore, CA 94550 USA. RP Caldeira, K (reprint author), Univ Calif Lawrence Livermore Natl Lab, Climate Syst Modeling Grp, Livermore, CA 94550 USA. RI Caldeira, Ken/E-7914-2011 NR 27 TC 120 Z9 149 U1 1 U2 35 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 28 PY 2000 VL 287 IS 5453 BP 620 EP 622 DI 10.1126/science.287.5453.620 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 278KR UT WOS:000084989400037 ER PT J AU Ghan, S Randall, D Xu, KM Cederwall, R Cripe, D Hack, J Iacobellis, S Klein, S Krueger, S Lohmann, U Pedretti, J Robock, A Rotstayn, L Somerville, R Stenchikov, G Sud, Y Walker, G Xie, SC Yio, J Zhang, MH AF Ghan, S Randall, D Xu, KM Cederwall, R Cripe, D Hack, J Iacobellis, S Klein, S Krueger, S Lohmann, U Pedretti, J Robock, A Rotstayn, L Somerville, R Stenchikov, G Sud, Y Walker, G Xie, SC Yio, J Zhang, MH TI A comparison of single column model simulations of summertime midlatitude continental convection SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; LARGE-SCALE MODELS; PLANETARY BOUNDARY-LAYER; COMMUNITY-CLIMATE-MODEL; ICE-CLOUD MICROPHYSICS; CUMULUS PARAMETERIZATION; PHASE MICROPHYSICS; ENSEMBLE MODELS; WATER CLOUDS; SCHEME AB Eleven different single-column models (SCMs) and one cloud ensemble model (CEM) are driven by boundary conditions observed at the Atmospheric Radiation Measurement (ARM) program southern Great Plains site for a 17 day period during the summer of 1995. Comparison of the model simulations reveals common signatures identifiable as products of errors in the boundary conditions. Intermodel differences in the simulated temperature, humidity, cloud, precipitation, and radiative fluxes reflect differences in model resolution or physical parameterizations, although sensitive dependence on initial conditions can also contribute to intermodel differences. All models perform well at times but poorly at others. Although none of the SCM simulations stands out as superior to the others, the simulation by the CEM is in several respects in better agreement with the observations than the simulations by the SCMs. Nudging of the simulated temperature and humidity toward observations generally improves the simulated cloud and radiation fields as well as the simulated temperature and humidity but degrades the precipitation simulation for models with large temperature and humidity biases without nudging. Although some of the intermodel differences have not been explained, others have been identified as model problems that can be or have been corrected as a result of the comparison. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Colorado State Univ, Dept Atmospher Sci, Ft Collins, CO 80523 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Calif San Diego, Scripps Inst Oceanog, Dept 0224, La Jolla, CA 92093 USA. Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. Univ Utah, Dept Meteorol, Salt Lake City, UT 84112 USA. Dalhousie Univ, Dept Phys & Oceanog, Halifax, NS, Canada. Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ USA. CSIRO, Aspendale, Vic 3195, Australia. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SUNY Stony Brook, Inst Terr & Planetary Atmospheres, Stony Brook, NY 11794 USA. RP Ghan, S (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM steve.ghan@pnl.gov RI Xu, Kuan-Man/B-7557-2013; Georgiy, Stenchikov/J-8569-2013; Rotstayn, Leon/A-1756-2012; Xie, Shaocheng/D-2207-2013; Robock, Alan/B-6385-2016; Ghan, Steven/H-4301-2011; Randall, David/E-6113-2011; Klein, Stephen/H-4337-2016; Lohmann, Ulrike/B-6153-2009; OI Xu, Kuan-Man/0000-0001-7851-2629; Rotstayn, Leon/0000-0002-2385-4223; Xie, Shaocheng/0000-0001-8931-5145; Ghan, Steven/0000-0001-8355-8699; Randall, David/0000-0001-6935-4112; Klein, Stephen/0000-0002-5476-858X; Lohmann, Ulrike/0000-0001-8885-3785; Robock, Alan/0000-0002-6319-5656 NR 80 TC 81 Z9 85 U1 0 U2 5 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 JAN 27 PY 2000 VL 105 IS D2 BP 2091 EP 2124 DI 10.1029/1999JD900971 PG 34 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 280DF UT WOS:000085086400016 ER PT J AU Suszcynsky, DM Kirkland, MW Jacobson, AR Franz, RC Knox, SO Guillen, JLL Green, JL AF Suszcynsky, DM Kirkland, MW Jacobson, AR Franz, RC Knox, SO Guillen, JLL Green, JL TI FORTE observations of simultaneous VHF and optical emissions from lightning: Basic phenomenology SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID RADIO INTERFEROMETRIC OBSERVATIONS; TRANSIONOSPHERIC PULSE PAIRS; RETURN STROKES; ELECTRIC-FIELD; SATELLITE-OBSERVATIONS; PEAK CURRENT; CLOUD; SIGNATURES; RADIATION; FLASHES AB Preliminary observations of simultaneous VHF and optical emissions from lightning as seen by the Fast on-Orbit Recording of Transient Events (FORTE) spacecraft are presented. VHF/optical waveform pairs are routinely collected both as individual lightning events and as sequences of events associated with cloud-to-ground (CG) and intracloud (IC) flashes. CG pulses can be distinguished from IC pulses on the basis of the properties of the VHF and optical waveforms but mostly on the basis of the associated VHF spectrograms. The VHF spectrograms are very similar to previous ground-based HF and VHF observations of lightning and show signatures associated with return strokes, stepped and dart leaders, attachment processes, and intracloud activity. For a typical IC flash, the FORTE-detected VHF is generally characterized by impulsive broadband bursts of emission, and the associated optical emissions are often highly structured. For a typical initial return stroke, the FORTE-detected VHF is generated by the stepped leader, the attachment process, and the actual return stroke. For a typical subsequent return stroke, the FORTE-detected VHF is mainly generated by dart leader processes. The detected optical signal in both return stroke cases is primarily produced by the in-cloud portion of the discharge and lags the arrival of the corresponding VHF emissions at the satellite by a mean value of 243 mu s. This delay is composed of a transit time delay (mean of 105 mu s) as the return stroke current propagates from the attachment point up into the region of in-cloud activity plus an additional delay due to the scattering of light during its traversal through the clouds. The broadening of the light pulse during its propagation through the clouds is measured and used to infer a mean of this scattering delay of about 138 mu s (41 km additional path length) for CG light. This value for the mean scattering delay is consistent with the Thomason and Krider [1982] model for light propagation through clouds. C1 Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. Sandia Natl Labs, Sensors & Elect Dept, Albuquerque, NM 87185 USA. RP Suszcynsky, DM (reprint author), Los Alamos Natl Lab, Space & Atmospher Sci Grp, MS D466, Los Alamos, NM 87545 USA. EM dsuszcynsky@lanl.gov OI Kirkland, Matt/0000-0002-1217-8864 NR 35 TC 44 Z9 46 U1 0 U2 3 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 JAN 27 PY 2000 VL 105 IS D2 BP 2191 EP 2201 DI 10.1029/1999JD900993 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 280DF UT WOS:000085086400022 ER PT J AU Ulagappan, N Frei, H AF Ulagappan, N Frei, H TI Redox chemistry of gaseous reactants inside photoexcited FeAlPO4 molecular sieve SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID NORMAL COORDINATE ANALYSIS; PHOTOCATALYTIC REACTIVITY; PHOTOLUMINESCENCE PROPERTY; MESOPOROUS ZEOLITES; REDUCTION; CATALYST; O-2; H2O; NO; DECOMPOSITION AB The reactivity of ligand-to-metal charge transfer excited Fe centers of FeAlPO4-5 molecular sieve at the gas-micropore interface has been probed by in situ FT-IR spectroscopy. Laser light in the region 350-430 nm was used to excite the metal centers, and reaction was induced between methanol or 2-propanol and O-2 Acetone and H2O are the observed products of the 2-propanol + O-2 system, while the reaction of methanol with O-2 yields formic acid, methyl formate, and H2O as final products. These originate from secondary thermal reaction of initially produced formaldehyde and hydrogen peroxide. The primary step of the proposed mechanism involves one-electron reduction of O-2 by transient Fe+II under concurrent donation of an electron to the hole of framework oxygen by the alcohol molecule. The efficient reaction suggests that the photoreduced Fe center of the molecular sieve has a substantially stronger reducing power than the conduction band electrons of dense-phase Fe2O3 semiconductor particles. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Frei, H (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Mailstop Calvin Lab, Berkeley, CA 94720 USA. NR 48 TC 12 Z9 15 U1 2 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 27 PY 2000 VL 104 IS 3 BP 490 EP 496 DI 10.1021/jp992991c PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 279UE UT WOS:000085062900009 ER PT J AU Wang, XB Nicholas, JB Wang, LS AF Wang, XB Nicholas, JB Wang, LS TI Photoelectron spectroscopy and theoretical calculations of SO4- and HSO4-: Confirmation of high electron affinities of SO4 and HSO4 SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID SULFATE-SOLUTIONS; AQUEOUS-SOLUTION; RAMAN; TEMPERATURES; ION AB We present a combined photoelectron spectroscopic and theoretical study of SO4- and HSO4- and their corresponding neutral species in the gas phase. We measured very high electron affinities for SO4 and HSO4, which are 5.10(0.10) and 4.75(0.10) eV, respectively. Theoretical calculations of the neutral and anionic species using both density functional and ab initio molecular orbital theory confirm the high electron affinities of the two species. The theoretically predicted vertical and adiabatic detachment energies are in good agreement with the experimental measurements. We find that both SO4- and SO4 have C-2v symmetry, whereas both HSO4- and HSO4 have C-s symmetry. We predict significant geometry changes between the equilibrium geometries of the anion species and the neutral species for both systems that are consistent with the broad nature of the measured photoelectron spectra. C1 Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Nicholas, JB (reprint author), Washington State Univ, Dept Phys, 2710 Univ Dr, Richland, WA 99352 USA. NR 20 TC 47 Z9 47 U1 3 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 27 PY 2000 VL 104 IS 3 BP 504 EP 508 DI 10.1021/jp992726r PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 279UE UT WOS:000085062900011 ER PT J AU Dimitrijevic, NM Takahashi, K Bartels, DM Jonah, CD Trifunac, AD AF Dimitrijevic, NM Takahashi, K Bartels, DM Jonah, CD Trifunac, AD TI Charged species in the radiolysis of supercritical CO2 SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID DIFFUSION-CONTROLLED REACTIONS; ELECTRON-TRANSFER REACTION; CARBON-DIOXIDE CLUSTERS; LASER FLASH-PHOTOLYSIS; PULSE-RADIOLYSIS; TRANSFER COMPLEX; SOLVENT DENSITY; FLUIDS; ATTACHMENT; RADICALS AB The pulse radiolysis technique has been employed in studying charge-transfer reactions of anionic C2O4- and cationic C2O4+ species in supercritical carbon dioxide (scCO(2)) over a range of reduced densities rho(r) = 0.36-1.5 and at a reduced temperature of T-r = 1.03. The absorption spectrum measured in the visible region with a maximum around 700 nm is assigned to the dimer cation C2O4+. The pressure dependence of charge-transfer reactions was examined using dimethylaniline (DMA), benzoquinone (BQ), and oxygen as charge accepters. The reaction rates of DMA with cations, and BQ with anions are at or near the diffusion-controlled limit. The rates decrease an order of magnitude with increase of pressure. The reaction of C2O4+ With oxygen is much slower with an almost constant rate over the pressure range examined. The measured race constants of electron-transfer reactions are analyzed in terms of the diffusion constants of reactants in scCO(2), and the dependence of measured and theoretical values on the bulk density is discussed. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Hokkaido Univ, Div Quantum Energy Engn, Sapporo, Hokkaido 060, Japan. RP Dimitrijevic, NM (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Takahashi, Kenji/C-8846-2011; Takahashi, Kenji/F-4885-2014 NR 49 TC 17 Z9 17 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 27 PY 2000 VL 104 IS 3 BP 568 EP 576 DI 10.1021/jp992859c PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 279UE UT WOS:000085062900020 ER PT J AU Bylaska, EJ Dixon, DA Felmy, AR AF Bylaska, EJ Dixon, DA Felmy, AR TI The free energies of reactions of chlorinated methanes with aqueous monovalent anions: Application of ab initio electronic structure theory SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; CONFIGURATION-INTERACTION CALCULATIONS; WAVE-FUNCTIONS; BENCHMARK CALCULATIONS; CARBON-TETRACHLORIDE; GAS-PHASE; MODEL; BORON; TRANSFORMATION AB The presence of different anionic species in natural waters can significantly alter the degradation rates of chlorinated methanes and other organic compounds. Favorable reaction energetics is a necessary feature of these nucleophilic substitution reactions that can result in the degradation of the chlorinated methanes; In this study, ab initio electronic structure theory is used to evaluate the free energies of reaction of a series of monovalent anionic species (OH-, SH-, NO3-, HCO3-, HSO3-, H2PO4-, and F-) that can occur in natural waters with the chlorinated methanes, CCl4, CCl3H, CCl2H2 and CClH3. The results of this investigation show that nucleophilic substitution reactions of OH-, SH-, HCO3-, and F- are significantly exothermic for chlorine displacement, NO3- reactions are slightly exothermic to thermoneutral, HSO3- reactions are slightly endothermic to thermoneutral and HSO4-, and H2PO4- reactions are significantly endothermic. In the case of OH-, SH-, and F- where there are limited experimental data, these results agree well with experiment. The results for HCO3- are potentially important given the near ubiquitous occurrence of carbonate species in natural waters. The calculations reveal that the degree of chlorination, with the exception of substitution of OH-, does not have a large effect on the Gibbs Tree energies of the substitution reactions. These results demonstrate that ab initio electronic structure methods can be used to calculate the reaction energetics of a potentially large number of organic compounds with other aqueous species in natural waters and can be used to help identify the potentially important environmental degradation reactions. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 68 TC 12 Z9 12 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 27 PY 2000 VL 104 IS 3 BP 610 EP 617 DI 10.1021/jp9923163 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 279UE UT WOS:000085062900026 ER PT J AU Hill, SE Feller, D AF Hill, SE Feller, D TI Theoretical conformational analysis of thiacrown macrocycles SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID ELECTRONIC-STRUCTURE CALCULATIONS; MOLECULAR-DYNAMICS SIMULATIONS; ROTATIONAL ISOMERIC STATES; CROWN THIOETHER CHEMISTRY; AB-INITIO; BASIS-SETS; ETHER COMPLEXES; FORCE-FIELD; MONTE-CARLO; FREE-ENERGY AB A gas phase conformational analysis was performed on four sulfur-containing macrocycles (9-thiacrown-3, 12-thiacrown-4, 15-thiacrown-5, and 18-thiacrown-6) using a combination of empirical and ab initio methods. Candidates for low-lying conformers were initially generated from high-temperature molecular dynamics simulations. A more computationally manageable subset of conformations was selected for further study based on their relative energies at successively higher levels of ab initio theory, The highest level of theory included second-order perturbation theory with the aug-cc-pVDZ basis set. The lowest conformation of 9-thiacrown-3 was found to have an exodentate C-2 structure with an electronic energy;that is 4 kcal/mol below the C-3 crystal structure. For 12-thiacrown-4, the lowest energy structure possesses D-4 structure in both the gas and crystal phase. In the case of 15-thiacrown-5 the lowest energy conformer possesses an oblong, partially exodentate, gas phase structure with C-2 symmetry. The crystal structure has C-1 symmetry and lies 3 kcal/mol higher in energy. 18-Thiacrown-6 has an exodentate C-2 symmetry, which is estimated with a large uncertainty to be 1 kcal/mol below the folded C-2 structure of the crystal. Zero-point vibrational effects shift relative energies by up to 0.3 kcal/mol across an energy span of 5-7 kcal/mol, but the effect on close-lying conformers is less. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Feller, D (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, MS K8-91,POB 999, Richland, WA 99352 USA. NR 81 TC 56 Z9 56 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 27 PY 2000 VL 104 IS 3 BP 652 EP 660 DI 10.1021/jp993188l PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 279UE UT WOS:000085062900031 ER PT J AU Davidson, AM Mellot, CF Eckert, J Cheetham, AK AF Davidson, AM Mellot, CF Eckert, J Cheetham, AK TI An inelastic neutron scattering and NIR-FT Raman spectroscopy study of chloroform and trichloroethylene in faujasites SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID VIBRATIONAL SPECTROSCOPY; ZEOLITE; ADSORPTION; SPECTROMETER; CATALYSIS; LOCATION; NMR; TCE; IR AB Molecular information about the nature and the strength of the interactions between chloroform and trichloroethylene (TCE) sorbates and siliceous FAU, NaY, and NaX zeolites was obtained by inelastic neutron scattering (INS) and Raman spectroscopies. The spectral features of the two sorbates differ in terms of their frequencies, splittings, and line widths from the ones of chloroform and TCE molecules in the gas phase. In conjunction with our simulation results, these differences are rationalized by assuming that, in siliceous FAU, the two sorbates undergo a nondissociative adsorption involving the formation of an H(sorbate)... O(framework) hydrogen bond and Cl(sorbate)... O(framework) van der Waals interactions, whereas in NaY and NaX, additional Cl(sorbate)... Na(+) electrostatic interactions are involved. Interestingly, no pi/Na(+) interaction takes place for TCE. These findings, which are in agreement with previous calorimetric and simulation results, confirm that the strength of the sorbate/zeolite interactions is correlated to the basicity of the zeolite and therefore increases in the sequence siliceous FAU < NaY < NaX, following the sequence of the heats of adsorption. C1 Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cheetham, AK (reprint author), Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. RI Garcia-Sanchez, Almudena/B-3303-2009 NR 43 TC 15 Z9 15 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 27 PY 2000 VL 104 IS 3 BP 432 EP 438 DI 10.1021/jp991515j PG 7 WC Chemistry, Physical SC Chemistry GA 279UK UT WOS:000085063300004 ER PT J AU Ford, JV Sumpter, BG Noid, DW Barnes, MD Hill, SC Hillis, DB AF Ford, JV Sumpter, BG Noid, DW Barnes, MD Hill, SC Hillis, DB TI Domain-size effects in optical diffraction from polymer/composite microparticles SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MORPHOLOGY-DEPENDENT RESONANCES; LIGHT-SCATTERING; POLYMER ELECTROLYTES; DIELECTRIC SPHERES; ELASTIC-SCATTERING; AEROSOL-PARTICLE; MICRODROPLETS; FLUORESCENCE; PRECISION; DROPLETS AB Poly(ethylene glycol) [PEG] microparticles were doped with ceramic or latex nanoparticles in order to examine domain-size and refractive index effects of nanometer-sized guest inclusions on two-dimensional diffraction patterns, Composite microparticles were examined for different inclusion sizes and polymer/nanoparticle weight ratios in order to determine the size and number-density threshold of detection for guest nanoparticles within the polymer host as indicated by fringe distortion in 2-D angular scattering. PEG host particles having a 10 mu m (nominal) diameter were formed with three different guest nanoparticles (Al2O3, TiO2 and latex nanospheres with respective sizes of 46, 29, and 14 nm), For the ceramic nanoparticle inclusions, distortion was observed at relative guest-host weight fractions of 5-10%. For the 14 nm latex inclusions, no distortion was observed at any weight fraction. A perturbation method was used to simulate the effect of nanometer-size inclusions on 2-D optical diffraction from polymer host microparticles and to suggest how the distortions should vary with inclusion size, refractive index, and number. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. USA, Res Lab, Adelphi, MD 20783 USA. RP Barnes, MD (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, MS 6142, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 28 TC 11 Z9 11 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 JAN 27 PY 2000 VL 104 IS 3 BP 495 EP 502 DI 10.1021/jp992843m PG 8 WC Chemistry, Physical SC Chemistry GA 279UK UT WOS:000085063300011 ER PT J AU Fukui, K Sumpter, BG Noid, DW Yang, C Tuzun, RE AF Fukui, K Sumpter, BG Noid, DW Yang, C Tuzun, RE TI Large-scale normal coordinate analysis of macromolecular systems: Thermal properties of polymer particles and crystals SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MOLECULAR MECHANICS CALCULATIONS; DYNAMICS; POLYETHYLENE; SIMULATIONS; CHAINS AB Using novel modifications to a sparse matrix solver (ARPACK), a complete spectral analysis has been achieved for a 6000 atom polymer system involving all 18 000 degrees of freedom. A comparison of the thermal properties and spectra of an annealed polymer particle and crystal is presented, The density of stales spectrum g(omega) shows a higher number of low-frequency modes for the polymer particle, which results in a higher heat capacity at low temperature. The distribution of energy level spacing shows some resemblance to that exhibited by random matrices. Finally. the displacement of low-frequency eigenvectors is: shown to have a larger amplitude on the surface than in the interior of either the particle or crystal. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. SUNY Coll Brockport, Dept Computat Sci, Brockport, NY 14420 USA. RP Fukui, K (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 45 TC 17 Z9 17 U1 0 U2 1 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 JAN 27 PY 2000 VL 104 IS 3 BP 526 EP 531 DI 10.1021/jp993149+ PG 6 WC Chemistry, Physical SC Chemistry GA 279UK UT WOS:000085063300015 ER PT J AU Bardeau, JF Parikh, AN Beers, JD Swanson, BI AF Bardeau, JF Parikh, AN Beers, JD Swanson, BI TI Phase behavior of a structurally constrained organic-inorganic crystal: Temperature-dependent infrared spectroscopy of silver n-dodecanethiolate SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; LANGMUIR-BLODGETT-FILMS; ORDER-DISORDER TRANSITIONS; NORMAL-ALKYL CHAINS; H STRETCHING MODES; NORMAL-ALKANES; CONFORMATIONAL DISORDER; VIBRATIONAL-SPECTRA; LAYERED STRUCTURE; THIN-FILMS AB Using temperature-dependent Fourier transform infrared (FTIR) spectroscopy, we probe the molecular level, chain-structural dynamics associated with solid-solid transitions between 25 and 250 degrees C in a layered inorganic-organic silver dodecanethiolate, AgS(CH2)(11)CH3. Spectroscopic evidence presented here establishes two major transitions: the transition occurring at similar to 130 degrees C is characterized by an abrupt, but fully reversible, change in the chain conformational order from an initial all-trans state to the one characterized by mixed or partial chain disorder. The observation of this phase transition is consistent with the previous predictions of a rapid and drastic change in the structural motif from an initial bilayer to the final micellar state. The second transition at about 190 degrees C, which is consistent with the previous assignment of micellar amorphous transition, is furthermore irreversible and represents thermal degradation of the material. Implications of these results for the general family of chain molecular assemblies in constrained molecular environments are discussed. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. RP Parikh, AN (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, POB 1663, Los Alamos, NM 87545 USA. RI PARIKH, ATUL/D-2243-2014 OI PARIKH, ATUL/0000-0002-5927-4968 NR 72 TC 46 Z9 46 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 JAN 27 PY 2000 VL 104 IS 3 BP 627 EP 635 DI 10.1021/jp992156v PG 9 WC Chemistry, Physical SC Chemistry GA 279UK UT WOS:000085063300029 ER PT J AU Davoudiasl, H Hewett, JL Rizzo, TG AF Davoudiasl, H Hewett, JL Rizzo, TG TI Bulk gauge fields in the Randall-Sundrum model SO PHYSICS LETTERS B LA English DT Article ID DIMENSIONS; SUPERSTRINGS; MILLIMETER; TEV AB We explore the consequences of placing the Standard Model gauge fields in the bulk of the recently proposed localized gravity model of Randall and Sundrum. We find that the Kaluza-Klein excitations of these fields are necessarily strongly coupled and we demonstrate that current precision electroweak data constrain the lowest states to lie above similar or equal to 23 TeV. Taking the weak scale to be similar to 1 TeV, the resulting implications on the model parameters force the bulk curvature, R-5, to be larger than the higher dimensional Planck scale, M, violating the consistency of the theory. In turn, to preserve \ R-5\ less than or similar to M-2, the weak scale must be pushed to greater than or similar to 100 TeV. Hence we conclude that. it is disfavored to place the Standard Model gauge fields in the bulk of this model as it is presently formulated. (C) 2000 Published by :Elsevier Science B.V. All rights reserved. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Davoudiasl, H (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 55 TC 368 Z9 369 U1 0 U2 0 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 JAN 27 PY 2000 VL 473 IS 1-2 BP 43 EP 49 DI 10.1016/S0370-2693(99)01430-6 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 280XF UT WOS:000085128500008 ER PT J AU Liu, XQ Mann, DB Suquet, C Springer, DL Smerdon, MJ AF Liu, XQ Mann, DB Suquet, C Springer, DL Smerdon, MJ TI Ultraviolet damage and nucleosome folding of the 5S ribosomal RNA gene SO BIOCHEMISTRY LA English DT Article ID PYRIMIDINE DIMER FORMATION; POSITIONED NUCLEOSOME; CORE PARTICLE; HUMAN-CELLS; DNA-REPAIR; PHOTOPRODUCTS; EXONUCLEASE; POLYMERASE; RESOLUTION; CHROMATIN AB The Xenopus borealis somatic 5S ribosomal RNA gene was used as a model system to determine the mutual effects of nucleosome folding and formation of ultraviolet (UV) photoproducts (primarily cis-syn cyclobutane pyrimidine dimers, or CPDs) in chromatin. We analyzed the preferred rotational and translational settings of 5S rDNA on the histone octamer surface after induction of up to 0.8 CPD/nucleosome core (2.5 kJ/m(2) UV dose). DNase I and hydroxyl radical footprints indicate that UV damage at these levels does not affect the average rotational setting of the 5S rDNA molecules. Moreover, a combination of nuclease trimming and restriction enzyme digestion indicates the preferred translational positions of the histone octamer are not affected by this level of UV damage, We also did not observe differences in the UV damage patterns of irradiated 5S rDNA before or after nucleosome formation, indicating there is little difference in the inhibition of nucleosome folding by specific CPD sites in the 5S rRNA gene. Conversely, nucleosome folding significantly restricts CPD formation at all sites in the three helical turns of the nontranscribed strand located in the dyad axis region of the nucleosome, where DNA is bound exclusively by the histone H3-H4 tetramer. Finally, modulation of the CPD distribution in a 14 nt long pyrimidine tract correlates with its rotational setting on the histone surface, when the strong sequence bias for CPD formation in this tract is minimized by normalization. These results help establish the mutual roles of histone binding and UV photoproducts on their formation in chromatin. C1 Washington State Univ, Sch Mol Biosci, Pullman, WA 99164 USA. Pacific NW Lab, Mol Biosci Dept, Richland, WA 99352 USA. RP Smerdon, MJ (reprint author), Washington State Univ, Sch Mol Biosci, Pullman, WA 99164 USA. FU NIEHS NIH HHS [ES02614] NR 42 TC 22 Z9 22 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD JAN 25 PY 2000 VL 39 IS 3 BP 557 EP 566 DI 10.1021/bi991771m PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 278LG UT WOS:000084990800008 PM 10642180 ER PT J AU Ellis, PJ Carlow, CKS Ma, D Kuhn, P AF Ellis, PJ Carlow, CKS Ma, D Kuhn, P TI Crystal structure of the complex of Brugia malayi cyclophilin and cyclosporin A SO BIOCHEMISTRY LA English DT Article ID A-INSENSITIVE CYCLOPHILIN; X-RAY STRUCTURE AB The resistance of the human parasite Brugia malayi to the antiparasitic activity of cyclosporin A (CsA) may arise from the presence of cyclophilins with relatively low affinity for the drug. The structure of the complex of B. malayi cyclophilin (BmCYP-1) and CsA, with eight independent copies in the asymmetric unit, has been determined at a resolution of 2.7 Angstrom. The low affinity of BmCYP-1 for CsA arises from incomplete preorganization of the binding site so that the formation of a hydrogen bond between His132 of BmCYP-1 and N-methylleucine 9 of CsA is associated with a shift in the backbone of approximately 1 Angstrom in this region. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. New England Biolabs Inc, Beverly, MA 01915 USA. RP Kuhn, P (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, POB 4249,Bin 69, Stanford, CA 94309 USA. NR 21 TC 6 Z9 9 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD JAN 25 PY 2000 VL 39 IS 3 BP 592 EP 598 DI 10.1021/bi991730q PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 278LG UT WOS:000084990800012 PM 10642184 ER PT J AU Li, D Xu, HF Guthrie, GD AF Li, D Xu, HF Guthrie, GD TI Zeolite-supported Ni and Mo catalysts for hydrotreatments II. HRTEM observations SO JOURNAL OF CATALYSIS LA English DT Article DE ultrastable Y zeolites; Ni-Mo oxides; Ni-Mo sulfides; hydrodesulfurization; environmental catalysis; high-resolution transmission electron microscopy ID TRANSMISSION ELECTRON-MICROSCOPY; METAL SULFIDE CATALYSTS; HYDRODESULFURIZATION CATALYSTS; MOLYBDENUM OXIDE; HYDROCRACKING; NICKEL; DEACTIVATION; ALUMINA; SURFACE; CO AB Calcined and sulfided Ni-Mo catalysts supported on ultrastable Y zeolite (USY), NaY zeolite, mordenite, and ZSM-5 were studied by high-resolution electron transmission microscopy (HRTEM) with selected-area electron diffraction (SAED) and energy-dispersive spectroscopy (EDS). Ni and Mo oxide aggregates were rarely observed in the USY-supported Ni-Mo catalyst, indicating that most of Ni and Mo may be incorporated into USY, e.g,, supercavities and possibly sodalite cages. However, there were a large number of(alpha-NiMoO4 aggregates of different particle sizes in NaY-, mordenite-, and ZSM-5-supported catalysts, and the mordenite-supported catalyst also contained MoO3 crystals. The alpha-NiMoO4 may be attached to the surface of substrates as individual particles or needle aggregates, it may be disseminated into mordenite particles, or it may even form an isolated sphere tin Ni-Mo/NaY) or a needle (in Ni-Mo/ZSM-5) aggregates. Thus, most of Ni and Mo in NaY-, mordenite-, and ZSM-5-supported catalysts preferentially formed aggregates, although some Mo may have been incorporated into NaY and ZSM-5. After sulfidation, small MoS2 aggregates containing some Ni were rarely but occasionally found on the surface of USY zeolite; however, there were a large number of such MoS2 aggregates on the surface of NaY. Separate and intergrown MoS2 and Ni sulfides aggregates were observed on the surface of mordenite and ZSM-5, The Ni sulfide might be identified by SAED and high-magnification images as troilite-like NiS and/or Ni9S8, but definitely not as NiS with millerite structure or Ni3S2 These results indicated that sulfidation does not extensively affect Ni and Mo that have been incorporated into the supercavity and/or sodalite cage of USY in calcined Ni-Mo/USY. After sulfidation, Ni-Mo sulfide species may have formed in the supercavity and possibly in the sodalite cage of the USY zeolite. However, in NaY-, mordenite-, and ZSM-5-supported Ni-Mo catalysts, Ni and Mo may have predominantly formed Ni-Mo sulfides or even separate Mo and Ni sulfide phases on the surface of the substrates. Thus, the USY-supported Ni-Mo catalyst had a much higher hydrodesulfurization (HDS) activity than the other zeolite-supported catalysts, which is attributed to both the highly dispersed Ni and/or Mo sulfide species in supercavities and possibly in sodalite cages of a USY zeolite, and the presence of Bronsted acidity in a USY zeolite we have demonstrated previously (Li, Dien, Nishijima, A., and Morris, D. E., J. Catal. 182, 339 (1999)). (C) 2000 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Earth & Environm Sci Div, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. RP Li, D (reprint author), Univ Calif Los Alamos Natl Lab, Earth & Environm Sci Div, EES-1,MS D-462, Los Alamos, NM 87545 USA. RI Li, Dien/N-6370-2014 NR 42 TC 15 Z9 19 U1 5 U2 30 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 JAN 25 PY 2000 VL 189 IS 2 BP 281 EP 296 DI 10.1006/jcat.1999.2723 PG 16 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 278PE UT WOS:000084997500004 ER PT J AU Chen, KD Xie, SB Iglesia, E Bell, AT AF Chen, KD Xie, SB Iglesia, E Bell, AT TI Structure and properties of zirconia-supported molybdenum oxide catalysts for oxidative dehydrogenation of propane SO JOURNAL OF CATALYSIS LA English DT Article ID X-RAY PHOTOELECTRON; RAMAN-SPECTROSCOPY; ALKANES; CLUSTERS; MOO3/ZRO2; MOLYBDATE; TEXTURE; OXYGEN AB Oxidative dehydrogenation (ODH) of propane was studied on zirconia-supported molybdenum oxide catalysts. The structure of the ZrO2 support and of the dispersed MoOx species was characterized by X-ray diffraction and by Raman and UV-visible spectroscopies. The structure of dispersed molybdena depends on the Mo surface density and on the temperature at which catalyst precursors are treated in air. Polymolybdate domains were detected by Raman at Mo surface densities below 5 Mo/nm(2). At higher surface densities, MoO3 and ZrMo2O8 are present; their relative concentrations depend on the pretreatment temperature. Below 773 K, MoO3 is the predominant structure at high surface densities, but ZrMo2O8 forms above 773 K. UV-visible edge energies decrease with increasing surface density for samples containing polymolybdate species, suggesting that MoOx domains become larger as the Mo surface density increases. ODH turnover rates decrease with increasing Mo surface density on samples containing polymolybdate species and MoO3. This trend is accompanied by an increase in the initial propene selectivity and in the vibrational frequency of Mo=O bonds. Higher Mo=O vibrational frequencies reflect stronger Mo=O bonds, which show lower ODH reactivity; therefore, the lower ODH reaction rates (per Mo atom) at higher Mo surface densities arise from the lower reactivity of Mo=O bonds, while higher initial propene selectivities arise either from the decrease of exposed Mo-O-Zr bonds or the lower reactivity of Mo=O bonds as the size of MoOx domains increases with increasing Mo surface density. At similar Mo surface densities, samples containing predominantly ZrMo2O8/ZrO2 show higher turnover rates and lower initial propene selectivities than those containing MoO3 species because the vibrational frequency of the Mo=O bond for ZrMo2O8/ZrO2 is lower than that for MoO3. ODH turnover rates over ZrMo2O8/ZrO2 also decreased with increasing Mo surface density, ultimately due to the increase of the particle size which leads to lower propane accessibility. (C) 2000 Academic Press. C1 Univ Calif Berkeley, Div Mat & Chem Sci, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Iglesia, E (reprint author), Univ Calif Berkeley, Div Mat & Chem Sci, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Song, Kunshan/C-7073-2008; Iglesia, Enrique/D-9551-2017; OI Iglesia, Enrique/0000-0003-4109-1001; Bell, Alexis/0000-0002-5738-4645 NR 38 TC 115 Z9 118 U1 4 U2 27 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 JAN 25 PY 2000 VL 189 IS 2 BP 421 EP 430 DI 10.1006/jcat.1999.2720 PG 10 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 278PE UT WOS:000084997500016 ER PT J AU Brisard, G Bertrand, N Ross, PN Markovic, NM AF Brisard, G Bertrand, N Ross, PN Markovic, NM TI Oxygen reduction and hydrogen evolution-oxidation reactions on Cu(hkl) surfaces SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Article DE oxygen reduction; hydrogen evolution-oxidation; copper surfaces ID SINGLE-CRYSTAL SURFACES; TRANSFORM INFRARED-SPECTROSCOPY; ENERGY-ELECTRON DIFFRACTION; SULFURIC-ACID ELECTROLYTE; IN-SITU STM; UNDERPOTENTIAL DEPOSITION; COPPER ANODES; PASSIVATION; ADSORPTION; ELECTROCHEMISTRY AB Taking advantage of the ring collection properties of the rotating ring-disk electrode with a single-crystal copper disk, we have shown that the oxygen reduction reaction and the hydrogen evolution-oxidation reactions on Cu(111) and Cu(100) surfaces in sulfuric acid are structure-sensitive processes. An interpretation of the structural sensitivity is presented, based on the premise of the structure-sensitive adsorption of (bi)sulfate anions. We have observed that the ordering kinetics of the (bi)sulfate on Cu(hkl) have an important rule in the mechanism of the oxygen reduction reaction. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Univ Sherbrooke, Dept Chim, Sherbrooke, PQ J1K 2R1, Canada. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Brisard, G (reprint author), Univ Sherbrooke, Dept Chim, 2500 Blvd Univ, Sherbrooke, PQ J1K 2R1, Canada. NR 35 TC 49 Z9 49 U1 4 U2 45 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-0728 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD JAN 25 PY 2000 VL 480 IS 1-2 BP 219 EP 224 DI 10.1016/S0022-0728(99)00463-5 PG 6 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA 328ZC UT WOS:000087880800023 ER PT J AU Triolo, F Triolo, A Triolo, R Londono, JD Wignall, GD McClain, JB Betts, DE Wells, S Samulski, ET DeSimone, JM AF Triolo, F Triolo, A Triolo, R Londono, JD Wignall, GD McClain, JB Betts, DE Wells, S Samulski, ET DeSimone, JM TI Critical micelle density for the self-assembly of block copolymer surfactants in supercritical carbon dioxide SO LANGMUIR LA English DT Article ID SMALL-ANGLE NEUTRON; X-RAY-SCATTERING; DISPERSION POLYMERIZATIONS; INDUCED MICELLIZATION; POLY(VINYL ACETATE); LIGHT-SCATTERING; CO2; MICROEMULSIONS; DIMENSIONS; SOLVENTS AB The parameters which influence the self-assembly of molecules in solution include the temperature and solvent quality, and this study illustrates the use of these variables to regulate the degree of association of block copolymer amphiphiles in highly compressible supercritical carbon dioxide. Small-angle neutron scattering (SANS) has been used to examine the association behavior of a block copolymer containing a CO2-phobic moiety, poly(vinyl acetate), and a CO2-philic block, poly(1,1-dihydroperfluoro-octylacrylate). By adjustment of the density of the medium through pressure and temperature profiling, the self-assembly can be reversibly controlled from unimers to core-shell spherical micelles and this establishes a critical micelle density (CMD), a phenomenon distinctive of highly compressible fluids, such as supercritical CO2. Mathematical modeling of the data in terms of core-shell micelle structures permits a detailed description of the structure and the degree of swelling (penetration) of the solvent into the different regions of the aggregates throughout this transition. C1 Univ Palermo, Dipartimento Chim Fis, I-90128 Palermo, Italy. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA. RP Triolo, R (reprint author), Univ Palermo, Dipartimento Chim Fis, I-90128 Palermo, Italy. 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 43 TC 55 Z9 56 U1 1 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JAN 25 PY 2000 VL 16 IS 2 BP 416 EP 421 DI 10.1021/la990140q PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 276RA UT WOS:000084890100023 ER PT J AU Wignall, GD Alamo, RG Londono, JD Mandelkern, L Kim, MH Lin, JS Brown, GM AF Wignall, GD Alamo, RG Londono, JD Mandelkern, L Kim, MH Lin, JS Brown, GM TI Morphology of blends of linear and short-chain branched polyethylenes in the solid state by small-angle neutron and X-ray scattering, differential scanning calorimetry, and transmission electron microscopy SO MACROMOLECULES LA English DT Article ID LIQUID PHASE-SEPARATION; LOW-DENSITY POLYETHYLENE; COPOLYMERS; FACILITY; MOLTEN; SANS AB Differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and small-angle neutron and X-ray scattering (SANS and SAXS, respectively) have been used to investigate the solid-state morphology of blends of linear (high-density) and model short-chain branched (linear-low-density) polyethylenes (HDPE/LLDPE). SANS indicates that the mixtures are homogeneous in the melt for all compositions when the ethyl branch content in the copolymer is low(i.e., <4 branches/100 backbone carbon atoms for a molecular weight of M-w similar to 10(5)). However, due to the structural and melting point differences between HDPE and LLDPE, the components may phase segregate in the solid state. The degree of separation is therefore controlled by the crystallization kinetics. DSC, TEM, SAXS, and SANS experiments have been used to investigate the solid-state morphology as a function of component composition, the thermal history, and the rate of cooling. It is shown that the combination of scattering, microscopy, and calorimetric techniques can provide detailed insight into the compositions of the various populations of the lamellar crystals and the amorphous regions that surround them. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Florida State Univ, Tallahassee, FL 32310 USA. Florida Agr & Mech Univ, Coll Engn, Dept Chem Engn, Tallahassee, FL 32310 USA. Exxon Chem Co, Baytown Polymers Ctr, Baytown, TX 77522 USA. Florida State Univ, Inst Mol Biophys, Tallahassee, FL 32306 USA. RP Wignall, GD (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 38 TC 57 Z9 58 U1 3 U2 27 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JAN 25 PY 2000 VL 33 IS 2 BP 551 EP 561 DI 10.1021/ma9912655 PG 11 WC Polymer Science SC Polymer Science GA 279AU UT WOS:000085021800055 ER PT J AU Daymond, MR Tome, CN Bourke, MAM AF Daymond, MR Tome, CN Bourke, MAM TI Measured and predicted intergranular strains in textured austenitic steel SO ACTA MATERIALIA LA English DT Article DE deformation mechanisms; residual stress; neutron diffraction; plasticity; mechanical properties ID RIETVELD REFINEMENT; ZIRCALOY-2 AB Tensile specimens were machined from heat-treated austenitic stainless steel plate prior to and after 70% reduction by uni-directional rolling. In addition to a single specimen cut from the as-received plate, two specimens were cut from the rolled plate, with axes parallel and perpendicular to the rolling direction, respectively. In situ measurements of the strain response of multiple hkl lattice planes to an applied uniaxial tensile load were made using neutron diffraction, to macroscopic plastic strains of around 1%. The experimental results are compared with predictions from a self-consistent Hill-Hutchinson model. The measured texture in the plate was approximately three Limes random; however, its effect on the hid response was small compared to the residual strains left by rolling. The apparent elastic modulus of the planes is affected by the residual strains, which is attributed to the effect of micro-plasticity. Interpretation of residual stress measurements, for both single peak and Rietveld measurements is considered in light of these results. (C) 2000 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos Neutron Sci Ctr, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Daymond, MR (reprint author), Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0QX, Oxon, England. RI Tome, Carlos/D-5058-2013; OI Daymond, Mark/0000-0001-6242-7489 NR 21 TC 78 Z9 78 U1 2 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD JAN 24 PY 2000 VL 48 IS 2 BP 553 EP 564 DI 10.1016/S1359-6454(99)00354-7 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 284ER UT WOS:000085318200016 ER PT J AU Kovar, D Bennison, SJ Readey, MJ AF Kovar, D Bennison, SJ Readey, MJ TI Crack stability and strength variability in alumina ceramics with rising toughness-curve behavior SO ACTA MATERIALIA LA English DT Article DE fracture toughness; ceramics; mechanical properties; microstructure; R-curve ID FLAW-TOLERANCE; GRAIN-SIZE; 2-PHASE CERAMICS; FRACTURE; MICROSTRUCTURE; RESISTANCE; RELIABILITY; GROWTH; MODEL AB Aluminas with four distinct microstructures have been fabricated to investigate the influence of grain size and grain morphology on strength variability. The four microstructures comprise two grain size scales and are characterized as either "equiaxed" with a narrow size distribution or "elongate" with a higher aspect ratio and a broader size distribution. indentation-strength tests indicate that only the coarse-grain, elongate microstructure exhibits a strong rising toughness-curve (T-curve or R-curve). Furthermore, in situ measurements demonstrate that the coarse-grain, elongate microstructure is the only one that displays significant stable crack extension from annealed indentation flaws free of contact-induced residual stress. Strength tests on polished specimens indicate that the highest mean strength is achieved in the fine-grain, equiaxed material with little or no T-curve. The lowest strength variability, however, is exhibited by the coarse-grain, elongate alumina and is rationalized in terms of the strong rising T-curve and its associated influence on crack stability. The study suggests that maximum reliability is achieved when the T-curve is sufficiently strong to stabilize the propagation of natural flaws en route to failure. (C) 2000 Acta Metallurgica Inc. Published by Elsevier Science Ltd. Ali rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Texas, Mat Inst, Austin, TX 78712 USA. Univ Texas, Dept Mech Engn, Austin, TX 78712 USA. EI Pont Nemours & Co Inc, Cent Res & Dev, Wilmington, DE 19880 USA. RP Kovar, D (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 30 TC 17 Z9 17 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD JAN 24 PY 2000 VL 48 IS 2 BP 565 EP 578 DI 10.1016/S1359-6454(99)00350-X PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 284ER UT WOS:000085318200017 ER PT J AU Stoughton, TE Miller, DR Yang, XS Hendrey, GM AF Stoughton, TE Miller, DR Yang, XS Hendrey, GM TI Footprint climatology estimation of potential control ring contamination at the Duke Forest FACTS-1 experiment site SO AGRICULTURAL AND FOREST METEOROLOGY LA English DT Article DE footprint; carbon dioxide enrichment; surface roughness; fetch; stability ID AIR CO2 ENRICHMENT; BOUNDARY-LAYER; FLUX MEASUREMENTS; SURFACE-LAYER; SCALAR FLUXES; PINE FOREST; MODELS; EVAPOTRANSPIRATION; PARAMETERS; RESPONSES AB Long-term airport weather observations, calibrated by on-site measurements, were used to create a footprint climatology for the Forest Atmosphere Carbon Dioxide Transfer and Storage-1 (FACTS-1) site in the Duke Forest, NC. The footprint was centered over each 30-m diameter control ring to estimate potential contamination from four CO2-enriched rings at the site. The footprint partitions the upward fluxing CO2 at any canopy-top point into relative contributions from grids in the surrounding forest, Additional footprints were generated for taller forest heights to estimate potential contamination levels at the sire as the forest grows. The results showed a small percentage of flux originating from enriched areas of the site reaching the control rings. The ring with the highest contamination received 1% of its total scalar flux from enriched areas. As the forest grows, the absolute contribution from the enriched rings will increase slightly, but the proportional contribution will decrease with time due to increases in canopy roughness and a larger footprint (greater fetch) during stable conditions. (C)2000 Elsevier Science B.V. All rights reserved. C1 Woodard & Curran Environm Sci, Portland, ME 04102 USA. Univ Connecticut, Dept Nat Resources Management & Engn, Storrs, CT 06269 USA. Brookhaven Natl Lab, Div Environm Biol & Instrumentat, Upton, NY 11973 USA. RP Stoughton, TE (reprint author), Woodard & Curran Environm Sci, Portland, ME 04102 USA. NR 31 TC 10 Z9 10 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-1923 J9 AGR FOREST METEOROL JI Agric. For. Meteorol. PD JAN 24 PY 2000 VL 100 IS 1 BP 73 EP 82 DI 10.1016/S0168-1923(99)00077-5 PG 10 WC Agronomy; Forestry; Meteorology & Atmospheric Sciences SC Agriculture; Forestry; Meteorology & Atmospheric Sciences GA 285PQ UT WOS:000085397800007 ER PT J AU Xin, Y James, EM Arslan, I Sivananthan, S Browning, ND Pennycook, SJ Omnes, F Beaumont, B Faurie, JP Gibart, P AF Xin, Y James, EM Arslan, I Sivananthan, S Browning, ND Pennycook, SJ Omnes, F Beaumont, B Faurie, JP Gibart, P TI Direct experimental observation of the local electronic structure at threading dislocations in metalorganic vapor phase epitaxy grown wurtzite GaN thin films SO APPLIED PHYSICS LETTERS LA English DT Article ID X-RAY-ABSORPTION; EDGE; SCATTERING; DEPOSITION; STATES; DIODES AB The electronic structure of pure edge threading dislocations in metalorganic vapor phase epitaxy grown wurtzite GaN thin films has been studied directly by atomic resolution Z-contrast imaging and electron energy loss spectroscopy in a scanning transmission electron microscope. Dislocation cores in n-type samples grown in N-rich conditions show no evidence for the high concentration of Ga vacancies predicted by previous theoretical calculations. Nitrogen K-edge spectra collected from edge dislocation cores show a sudden and significant increase in the intensity of the first fine-structure peak immediately above the edge onset compared to the bulk spectra. The origin of this increase is discussed. (C) 2000 American Institute of Physics. [S0003-6951(00)03404-5]. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. CNRS, CRHEA, F-06560 Valbonne, France. RP Xin, Y (reprint author), Univ Illinois, Dept Phys, Chicago, IL 60607 USA. OI Browning, Nigel/0000-0003-0491-251X NR 23 TC 53 Z9 53 U1 1 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 24 PY 2000 VL 76 IS 4 BP 466 EP 468 DI 10.1063/1.125789 PG 3 WC Physics, Applied SC Physics GA 276LP UT WOS:000084879500024 ER PT J AU Kim, SH Kim, DJ Maria, JP Kingon, AI Streiffer, SK Im, J Auciello, O Krauss, AR AF Kim, SH Kim, DJ Maria, JP Kingon, AI Streiffer, SK Im, J Auciello, O Krauss, AR TI Influence of Pt heterostructure bottom electrodes on SrBi2Ta2O9 thin film properties SO APPLIED PHYSICS LETTERS LA English DT Article AB The properties of SrBi2Ta2O9 (SBT) films, such as remanent polarization and leakage current density, are closely related to the film/electrode interface and surface roughness of the underlying electrode. SBT films grown on stable Pt/TiO2/SiO2/Si and Pt/ZrO2/SiO2/Si substrates exhibit high remanent polarization, low leakage current density, and low voltage saturation as compared to SBT films synthesized on Pt/Ti/SiO2/Si. It is shown that severe diffusion of Ti from the Ti interlayer onto the surface of the Pt bottom electrode and the increased surface roughness of this electrode stack play key roles in degradation of SBT properties. (C) 2000 American Institute of Physics. [S0003-6951(00)04304-7]. C1 N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem & Mat Sci, Argonne, IL 60439 USA. RP Kim, SH (reprint author), N Carolina State Univ, Dept Mat Sci & Engn, Box 7907, Raleigh, NC 27695 USA. RI KIM, DONG-JOO/C-2277-2008; Streiffer, Stephen/A-1756-2009 NR 9 TC 39 Z9 39 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 24 PY 2000 VL 76 IS 4 BP 496 EP 498 DI 10.1063/1.125799 PG 3 WC Physics, Applied SC Physics GA 276LP UT WOS:000084879500034 ER PT J AU Johnson, JA Johnson, CE Holland, D Sears, A Bent, JF Appleyard, PG Thomas, MF Hannon, AC AF Johnson, JA Johnson, CE Holland, D Sears, A Bent, JF Appleyard, PG Thomas, MF Hannon, AC TI Ternary alkali stannosilicate glasses: a Mossbauer and neutron diffraction study SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID SHORT-RANGE AB Neutron diffraction and Mossbauer spectroscopic measurements have been performed on four series of ternary alkali stannosilicate glasses of nominal composition (SnO0.5-x (M2O)(x) (SiO2)(0.5) with 0 less than or equal to x less than or equal to 0.2, where the modifier cations were M = Li, Na, K and Rb. The data show that the tin is predominantly three co-ordinate and that the length of the Sn-O bond and the O-Sn-O angle decrease with increasing modifier concentration x. This reduction increases with increasing size of the modifier cation, and is opposite in sign to the macroscopic molar volume which increases with modifier content. The Sn-119 Mossbauer spectra of these samples showed that most of the tin is in the Sn2+ state and that the isomer shift and quadrupole splitting vary approximately linearly with the Sn-O bond length and O-Sn-O bond angle for each series. This is consistent with a contraction of the 5p electron orbitals of the tin atoms and an increase in the symmetry of the Ligand environment as modifier ions are added. C1 Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ Liverpool, Dept Phys, Liverpool L69 3BX, Merseyside, England. Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. Liverpool John Moores Univ, Sch Built Environm, Liverpool L3 5UG, Merseyside, England. Rutherford Appleton Lab, ISIS Facil, Didcot OX11 0RA, Oxon, England. RP Johnson, JA (reprint author), Argonne Natl Lab, Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Johnson, Jacqueliine/G-7365-2011; Johnson, Jacqueline/P-4844-2014; OI Johnson, Jacqueline/0000-0003-0830-9275; Hannon, Alex/0000-0001-5914-1295 NR 13 TC 14 Z9 14 U1 0 U2 5 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 JAN 24 PY 2000 VL 12 IS 3 BP 213 EP 230 DI 10.1088/0953-8984/12/3/302 PG 18 WC Physics, Condensed Matter SC Physics GA 281XX UT WOS:000085187700005 ER PT J AU Russell, LB Hunsicker, PR Hack, AM Ashley, T AF Russell, LB Hunsicker, PR Hack, AM Ashley, T TI Effect of the topoisomerase-II inhibitor etoposide on meiotic recombination in male mice SO MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS LA English DT Article DE etoposide; recombination; topoisomerase-II; meiosis; germ-cell-stages; spermatocytes ID MISMATCH REPAIR; CROSSING-OVER; MALE-MOUSE; DNA TOPOISOMERASES; GERM-CELLS; IN-VIVO; MEIOSIS; ANEUPLOIDY; PROTEIN; INDUCTION AB Unlike other chemicals that have been tested in mammalian germ cells, the type-II topoisomerase inhibitor etoposide exhibits significant mutagenicity in primary spermatocytes. Because this is the cell stage during which meiotic recombination normally occurs, and because topoisomerases play a role in recombination, we studied the effect of etoposide on crossing-over in male mice. Exposure to those meiotic prophase stages (probably early to mid-pachytene) during which specific-locus deletion mutations can be induced resulted in decreased crossing-over in the p-Tyr(c) interval of mouse chromosome 7. Accompanying cytological studies with fluorescent antibodies indicated that while there was no detectable effect on the number of recombination nodules (MLH1 foci), there were marked changes in the stage of appearance and localization of RAD51 and RPA proteins. These temporal and spatial protein patterns suggest the formation of multiple lesions in the DNA after MLH1 has already disappeared from spermatocytes. Since etoposide blocks religation of the cut made by type II topoisomerases, repair of DNA damage may result in rejoining of the original DNA strands, undoing the reciprocal exchange that had already occurred and resulting in reduced crossing-over despite a normal frequency of MLH1 foci. Crossing-over could conceivably be affected differentially in different chromosomal regions. If, however, the predominant action of etoposide is to decrease homologous meiotic recombination, the chemical could be expected to increase nondisjunction, an event associated with human genetic risk; Three periods in spermatogenesis respond to etoposide in different ways. Exposure of (a) late differentiating spermatogonia (and, possibly, preleptotene spermatocytes) results in cell death; (b) early- to mid-pachytene induces specific-locus deletions and crossover reduction; and, (c) late pachytene-through-diakinesis leads to genetically unbalanced conceptuses as a result of clastogenic damage. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Yale Univ, Sch Med, Dept Genet, New Haven, CT 06510 USA. RP Russell, LB (reprint author), Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. FU NIEHS NIH HHS [Y1-ES-8048]; NIGMS NIH HHS [GM-49779] NR 39 TC 19 Z9 19 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1383-5718 J9 MUTAT RES-GEN TOX EN JI Mutat. Res. Genet. Toxicol. Environ. Mutagen. PD JAN 24 PY 2000 VL 464 IS 2 BP 201 EP 212 DI 10.1016/S1383-5718(99)00185-0 PG 12 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 278XP UT WOS:000085014500005 PM 10648907 ER PT J AU Arkani-Hamed, N Dimopoulos, S Dvali, G Kaloper, N AF Arkani-Hamed, N Dimopoulos, S Dvali, G Kaloper, N TI Infinitely large new dimensions SO PHYSICAL REVIEW LETTERS LA English DT Article AB We construct intersecting brane configurations in anit-de Sitter (AdS) space which localize gravity to the intersection region, generalizing the trapping of gravity to any number n of infinite extra dimensions. Since the 4D Planck scale M-Pl is determined by the fundamental Planck scale M-* and the AdS radius L via the familiar relation M-Pl(2) similar to M-*(2+n) L-n we get two kinds of theories with TeV scale quantum gravity and submillimeter deviations from Newton's law. With M-* similar to TeV and L similar to submillimeter, we recover the phenomenology of theories with large extra dimensions; Alternatively, if M-* similar to L similar to M-Pl, and our 3-brane is at a distance of similar to 100M(Pl)(-1) from the intersection, we obtain a theory with an exponential determination of the weak/Planck hierarchy. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94530 USA. Lawrence Berkeley Lab, Theory Grp, Berkeley, CA 94530 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. NYU, Dept Phys, New York, NY 10003 USA. ICTP, Trieste, Italy. RP Arkani-Hamed, N (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94530 USA. NR 13 TC 232 Z9 233 U1 1 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 JAN 24 PY 2000 VL 84 IS 4 BP 586 EP 589 DI 10.1103/PhysRevLett.84.586 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700002 ER PT J AU Geer, S Marriner, J Martens, M Ray, RE Streets, J Wester, W Hu, M Snow, GR Armstrong, T Buchanan, C Corbin, B Lindgren, M Muller, T Gustafson, R AF Geer, S Marriner, J Martens, M Ray, RE Streets, J Wester, W Hu, M Snow, GR Armstrong, T Buchanan, C Corbin, B Lindgren, M Muller, T Gustafson, R TI New limit on CPT violation SO PHYSICAL REVIEW LETTERS LA English DT Article ID FERMILAB ANTIPROTON ACCUMULATOR; SEARCH; DECAY; FLUX AB A search for antiproton decay has been made at the Fermilab Antiproton Accumulator. Limits are placed on fifteen antiproton decay modes. The results are used to place limits on the characteristic mass scale,,lx that could be associated with CPT violation accompanied by baryon number violation. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Nebraska, Lincoln, NE 68588 USA. Penn State Univ, University Pk, PA 16802 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Michigan, Ann Arbor, MI 48109 USA. RP Geer, S (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 28 TC 2 Z9 2 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 JAN 24 PY 2000 VL 84 IS 4 BP 590 EP 593 DI 10.1103/PhysRevLett.84.590 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700003 ER PT J AU Bai, JZ Ban, Y Bian, JG Chen, GP Chen, HF Chen, J Chen, JC Chen, Y Chen, YB Chen, YQ Cheng, BS Cui, XZ Ding, HL Dong, LY Du, ZZ Dunwoodie, W Gao, CS Gao, ML Gao, SQ Gu, JH Gu, SD Gu, WX Gu, YF Guo, YN Guo, ZJ Han, SW Han, Y Harris, FA He, J He, JT He, KL He, M Heng, YK Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Hu, XQ Huang, GS Huang, YZ Izen, JM Jiang, CH Jin, Y Jones, BD Ju, X Ke, ZJ Kong, D Lai, YF Lang, PF Li, CG Li, D Li, HB Li, J Li, JC Li, PQ Li, RB Li, W Li, WG Li, XH Li, XN Liu, HM Liu, J Liu, RG Liu, Y Lou, XC Lu, F Lu, JG Luo, XL Ma, EC Ma, JM Malchow, R Mao, HS Mao, ZP Meng, XC Nie, J Olsen, SL Paluselli, D Pan, LJ Qi, ND Qi, XR Qian, CD Qiu, JF Qu, YH Que, YK Rong, G Shao, YY Shen, BW Shen, DL Shen, H Shen, XY Sheng, HY Shi, HZ Song, XF Sun, F Sun, HS Sun, Y Sun, YZ Tang, SQ Toki, W Tong, GL Varner, GS Wang, F Wang, LS Wang, LZ Wang, M Wang, P Wang, PL Wang, SM Wang, TJ Wang, YY Wei, CL Wu, N Wu, YG Xi, DM Xia, XM Xie, PP Xie, Y Xie, YH Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, HX Yang, J Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yu, CS Yu, CX Yu, GW Yu, YH Yu, ZQ Yuan, CZ Yuan, Y Zhang, BY Zhang, C Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JW Zhang, L Zhang, LS Zhang, P Zhang, QJ Zhang, SQ Zhang, XY Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, JW Zhao, M Zhao, WR Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhou, BQ Zhou, GP Zhou, HS Zhou, L Zhu, KJ Zhu, QM Zhu, YC Zhu, YS Zhuang, BA AF Bai, JZ Ban, Y Bian, JG Chen, GP Chen, HF Chen, J Chen, JC Chen, Y Chen, YB Chen, YQ Cheng, BS Cui, XZ Ding, HL Dong, LY Du, ZZ Dunwoodie, W Gao, CS Gao, ML Gao, SQ Gu, JH Gu, SD Gu, WX Gu, YF Guo, YN Guo, ZJ Han, SW Han, Y Harris, FA He, J He, JT He, KL He, M Heng, YK Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Hu, XQ Huang, GS Huang, YZ Izen, JM Jiang, CH Jin, Y Jones, BD Ju, X Ke, ZJ Kong, D Lai, YF Lang, PF Li, CG Li, D Li, HB Li, J Li, JC Li, PQ Li, RB Li, W Li, WG Li, XH Li, XN Liu, HM Liu, J Liu, RG Liu, Y Lou, XC Lu, F Lu, JG Luo, XL Ma, EC Ma, JM Malchow, R Mao, HS Mao, ZP Meng, XC Nie, J Olsen, SL Paluselli, D Pan, LJ Qi, ND Qi, XR Qian, CD Qiu, JF Qu, YH Que, YK Rong, G Shao, YY Shen, BW Shen, DL Shen, H Shen, XY Sheng, HY Shi, HZ Song, XF Sun, F Sun, HS Sun, Y Sun, YZ Tang, SQ Toki, W Tong, GL Varner, GS Wang, F Wang, LS Wang, LZ Wang, M Wang, P Wang, PL Wang, SM Wang, TJ Wang, YY Wei, CL Wu, N Wu, YG Xi, DM Xia, XM Xie, PP Xie, Y Xie, YH Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, HX Yang, J Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yu, CS Yu, CX Yu, GW Yu, YH Yu, ZQ Yuan, CZ Yuan, Y Zhang, BY Zhang, C Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JW Zhang, L Zhang, LS Zhang, P Zhang, QJ Zhang, SQ Zhang, XY Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, JW Zhao, M Zhao, WR Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhou, BQ Zhou, GP Zhou, HS Zhou, L Zhu, KJ Zhu, QM Zhu, YC Zhu, YS Zhuang, BA CA BES Collaboration TI Measurement of the total cross section for hadronic production by e(+)e(-) annihilation at energies between 2.6-5 GeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID E+E ANNIHILATION; PHYSICS; ALPHA(M(Z)(2)); ALPHA(M-Z(2)); MUON AB Using the upgraded Beijing Spectrometer we have measured the total cross section for e(+) e(-) annihilation into hadronic final states at center-of-mass energies of 2.6, 3.2,.3.4, 3.55, 4.6, and 5.0 GeV. Values of R, sigma(e(+)e(-) --> hadrons)/sigma(e(+)e(-) --> mu(+)mu(-)), are determined. C1 Inst High Energy Phys, Beijing 100039, Peoples R China. Colorado State Univ, Ft Collins, CO 80523 USA. Hangzhou Univ, Hangzhou 310028, Peoples R China. Peking Univ, Beijing 100871, Peoples R China. Shandong Univ, Jinan 250100, Peoples R China. Shanghai Jiao Tong Univ, Shanghai 200030, Peoples R China. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Sci & Technol China, Anhua 230026, Peoples R China. Univ Texas, Richardson, TX 75083 USA. RP Bai, JZ (reprint author), Inst High Energy Phys, Beijing 100039, Peoples R China. RI Chen, Yu/E-3788-2012; dong, liaoyuan/A-5093-2015 OI dong, liaoyuan/0000-0002-4773-5050 NR 27 TC 128 Z9 134 U1 1 U2 11 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 JAN 24 PY 2000 VL 84 IS 4 BP 594 EP 597 DI 10.1103/PhysRevLett.84.594 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700004 ER PT J AU Aranson, IS Pismen, LM AF Aranson, IS Pismen, LM TI Interaction of vortices in a complex vector field and stability of a "vortex molecule" SO PHYSICAL REVIEW LETTERS LA English DT Article ID GINZBURG-LANDAU EQUATION; SPIRAL WAVES; OSCILLATORY MEDIA; BIFURCATIONS; INSTABILITY; LASER AB We consider interaction of vortices in the vector complex Ginzburg-Landau equation (CVGLE). In the limit of small field coupling, it is found analytically that the interaction between well-separated defects in two different fields is long ranged, in contrast to the interaction between defects in the same field which falls off exponentially. In a certain region of parameters of CVGLE, we find stable rotating bound states of two defects-a "vortex molecule." C1 Argonne Natl Lab, Argonne, IL 60439 USA. Technion Israel Inst Technol, Dept Chem Engn, IL-32000 Haifa, Israel. RP Aranson, IS (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Pismen, Len/B-3500-2008; Aranson, Igor/I-4060-2013 NR 16 TC 25 Z9 25 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 JAN 24 PY 2000 VL 84 IS 4 BP 634 EP 637 DI 10.1103/PhysRevLett.84.634 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700014 ER PT J AU Neil, GR Bohn, CL Benson, SV Biallas, G Douglas, D Dylla, HF Evans, R Fugitt, J Grippo, A Gubeli, J Hill, R Jordan, K Li, R Merminga, L Piot, P Preble, J Shinn, M Siggins, T Walker, R Yunn, B AF Neil, GR Bohn, CL Benson, SV Biallas, G Douglas, D Dylla, HF Evans, R Fugitt, J Grippo, A Gubeli, J Hill, R Jordan, K Li, R Merminga, L Piot, P Preble, J Shinn, M Siggins, T Walker, R Yunn, B TI Sustained kilowatt lasing in a free-electron laser with same-cell energy recovery SO PHYSICAL REVIEW LETTERS LA English DT Article ID FEL AB Jefferson Laboratory's kW-level infrared free-electron laser utilizes a superconducting accelerator that recovers about 75% of the electron-beam power. In achieving first lasing, the accelerator operated "straight ahead" to deliver 38-MeV, 1.1-mA cw current for lasing near 5 mu m, The waste beam was sent directly to a dump while producing stable operation at up to 311 W. Utilizing the recirculation loop to send the electron beam back to the linac for energy recovery, the machine has now recovered cw average currents up to 5 mA, and has lased cw with up to 1720 W output at 3.1 mu m. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Neil, GR (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. OI EVANS, ROBIN/0000-0002-7988-3189; piot, philippe/0000-0002-4799-292X NR 19 TC 192 Z9 201 U1 1 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 24 PY 2000 VL 84 IS 4 BP 662 EP 665 DI 10.1103/PhysRevLett.84.662 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700021 ER PT J AU Montgomery, DS Johnson, RP Rose, HA Cobble, JA Fernandez, JC AF Montgomery, DS Johnson, RP Rose, HA Cobble, JA Fernandez, JC TI Flow-induced beam steering in a single laser hot spot SO PHYSICAL REVIEW LETTERS LA English DT Article ID TRANSVERSE-PLASMA FLOW; DEFLECTION AB The transmitted angular distribution of a 527 nm nearly diffraction-limited laser is measured after it propagates through a plasma with supersonic transverse now. The laser beam is deflected by as much as 10 degrees and exhibits bowlike features in the now direction, which is attributed to now-induced beam steering. The finite interaction volume allows for direct comparison with a 3D hydrodynamic simulation, which is in good agreement with details of the experiment. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Montgomery, DS (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Fernandez, Juan/H-3268-2011; OI Fernandez, Juan/0000-0002-1438-1815; Montgomery, David/0000-0002-2355-6242 NR 14 TC 27 Z9 27 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 JAN 24 PY 2000 VL 84 IS 4 BP 678 EP 681 DI 10.1103/PhysRevLett.84.678 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700025 ER PT J AU Floro, JA Sinclair, MB Chason, E Freund, LB Twesten, RD Hwang, RQ Lucadamo, GA AF Floro, JA Sinclair, MB Chason, E Freund, LB Twesten, RD Hwang, RQ Lucadamo, GA TI Novel SiGe island coarsening kinetics: Ostwald ripening and elastic interactions SO PHYSICAL REVIEW LETTERS LA English DT Article ID THIN-FILMS; EPITAXIAL-GROWTH; GE; SI(001); RELAXATION; SURFACE AB Real-time light scattering measurements of coherent island coarsening during SiGe/Si heteroepitaxy reveal unusual kinetics. In particular, the mean island volume increases superlinearly with time, while the areal density of islands decreases at a faster-than-linear rate. Neither observation is consistent with standard considerations of Ostwald ripening. Modification of the standard theory to incorporate the effect of elastic interactions in the growing island array reproduces the observed behavior. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Brown Univ, Div Engn, Providence, RI 02912 USA. Univ Illinois, Ctr Microanal Mat, Urbana, IL 61801 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. RP Floro, JA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 22 TC 111 Z9 113 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 JAN 24 PY 2000 VL 84 IS 4 BP 701 EP 704 DI 10.1103/PhysRevLett.84.701 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700031 ER PT J AU de Swiet, TM Yarger, JL Wagberg, T Hone, J Gross, BJ Tomaselli, M Titman, JJ Zettl, A Mehring, M AF de Swiet, TM Yarger, JL Wagberg, T Hone, J Gross, BJ Tomaselli, M Titman, JJ Zettl, A Mehring, M TI Electron spin density distribution in the polymer phase of CsC60: Assignment of the NMR spectrum SO PHYSICAL REVIEW LETTERS LA English DT Article ID METAL-INSULATOR-TRANSITION; NUCLEAR-MAGNETIC-RESONANCE; ROTATIONAL-ECHO; RBC60; KC60; RB1C60; RB; CS; FULLERIDES; SCATTERING AB We present high resolution Cs-133-C-13 double resonance NMR data and C-13-C-13 NMR correlation spectra of C-13 enriched samples of the polymeric phase of CsC60. These data lead to a partial assignment of the lines in the C-13 NMR spectrum of CSC60 to the carbon positions on the C-60 molecule. A plausible completion of the assignment can be made on the basis of an ab initio calculation, The data support the view that the conduction electron density is concentrated at the C60 "equator," away from the interfullerene bonds. C1 Univ Nottingham, Sch Chem, Nottingham NG7 2RD, England. Univ Wyoming, Dept Chem, Laramie, WY 82071 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EO Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Stuttgart, Inst Phys 2, D-70550 Stuttgart, Germany. RP de Swiet, TM (reprint author), Univ Nottingham, Sch Chem, Nottingham NG7 2RD, England. RI Titman, Jeremy/F-8262-2010; Hone, James/E-1879-2011; Wagberg, Thomas/C-2912-2008; Yarger, Jeff/L-8748-2014; Zettl, Alex/O-4925-2016 OI Titman, Jeremy/0000-0001-9758-9146; Hone, James/0000-0002-8084-3301; Wagberg, Thomas/0000-0002-5080-8273; Yarger, Jeff/0000-0002-7385-5400; Zettl, Alex/0000-0001-6330-136X NR 36 TC 24 Z9 24 U1 1 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 JAN 24 PY 2000 VL 84 IS 4 BP 717 EP 720 DI 10.1103/PhysRevLett.84.717 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700035 ER PT J AU Yu, ZG Smith, DL Saxena, A Martin, RL Bishop, AR AF Yu, ZG Smith, DL Saxena, A Martin, RL Bishop, AR TI Molecular geometry fluctuation model for the mobility of conjugated polymers SO PHYSICAL REVIEW LETTERS LA English DT Article ID POLY(P-PHENYLENE VINYLENE); CHARGE-TRANSPORT; FIELD; DEPENDENCE; DISORDER AB We present a model to describe electrical transport in dense films of conjugated polymers. The essen tial physical features of the model are as follows: (i) thermal fluctuations in the molecular geometry of the polymer modify the energy levels of localized electronic states in the material, and (ii) the primary restoring force for these fluctuations is steric, which leads to spatial correlation in the energies of the localized electronic states. The model describes the electric field dependence of the mobility and explains the carrier density dependences of mobility observed in polymer diodes and field effect transistors. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Yu, ZG (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Yu, Z/B-5547-2009; OI , Zhi-Gang/0000-0002-1376-9025 NR 20 TC 125 Z9 125 U1 1 U2 16 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 JAN 24 PY 2000 VL 84 IS 4 BP 721 EP 724 DI 10.1103/PhysRevLett.84.721 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700036 PM 11017356 ER PT J AU Woicik, JC Nelson, EJ Pianetta, P AF Woicik, JC Nelson, EJ Pianetta, P TI Direct measurement of valence-charge asymmetry by x-ray standing waves SO PHYSICAL REVIEW LETTERS LA English DT Article ID SURFACE-STRUCTURE DETERMINATION AB By monitoring valence-photoelectron emission under condition of strong x-ray Bragg reflection, we have determined that a majority of GaAs valence oharge resides on the anion sites of this heteropolar crystal, in quantitative agreement with the GaAs bond polarity as calculated from the Hartree-Fock term values. In contrast, the valence-charge distribution in Ge is found to be symmetric. In both cases, the valence emission is found to be closely coupled to the atomic cores. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Woicik, JC (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 15 TC 14 Z9 14 U1 1 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 JAN 24 PY 2000 VL 84 IS 4 BP 773 EP 776 DI 10.1103/PhysRevLett.84.773 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700049 PM 11017369 ER PT J AU Lurio, LB Lumma, D Sandy, AR Borthwick, MA Falus, P Mochrie, SGJ Pelletier, JF Sutton, M Regan, L Malik, A Stephenson, GB AF Lurio, LB Lumma, D Sandy, AR Borthwick, MA Falus, P Mochrie, SGJ Pelletier, JF Sutton, M Regan, L Malik, A Stephenson, GB TI Absence of scaling for the intermediate scattering function of a hard-sphere suspension: Static and dynamic x-ray scattering from concentrated polystyrene latex spheres SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHOTON-CORRELATION SPECTROSCOPY; COLLOIDAL SUSPENSIONS; BROWNIAN-MOTION; DIFFUSION; PARTICLES; DISPERSIONS; SYSTEMS AB X-ray photon correlation spectroscopy and small-angle scattering measurements are presented of the dynamics and structure of concentrated suspensions of charge-stabilized polystyrene latex spheres dispersed in glycerol, for volume fractions from 3% to 52%. The static structures of the suspensions show essentially hard-sphere behavior, and the short-time dynamics shows good agreement with predictions for the wave-vector-dependent collective diffusion coefficient, However, the intermediate scattering function is found to violate a scaling behavior found previously for a sterically stabilized hard-sphere suspension [P.N. Segre and P.N. Pusey, Phys. Rev. Lett. 77, 771 (1996)]. C1 MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. Yale Univ, Dept Mol Biophys & Biochem, New Haven, CT 06520 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Lurio, LB (reprint author), MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. NR 23 TC 57 Z9 59 U1 4 U2 24 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 JAN 24 PY 2000 VL 84 IS 4 BP 785 EP 788 DI 10.1103/PhysRevLett.84.785 PG 4 WC Physics, Multidisciplinary SC Physics GA 276RT UT WOS:000084891700052 PM 11017372 ER PT J AU Fang, XG Watkin, JG Warner, BP AF Fang, XG Watkin, JG Warner, BP TI Ytterbium trichloride-catalyzed allylation of aldehydes with allyltrimethylsilane SO TETRAHEDRON LETTERS LA English DT Article DE aldehydes; allylation; dienes; lanthanides ID COMMERCIAL FORMALDEHYDE SOLUTION; SILYL ENOL ETHERS; SCANDIUM TRIFLUOROMETHANESULFONATE; CARBONYL-COMPOUNDS; AQUEOUS-MEDIA; LEWIS-ACIDS AB Ytterbium chloride (YbCl3) is found to be an effective catalyst for the allylation of both aromatic and aliphatic aldehydes using allyltrimethylsilane. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Warner, BP (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Mail Stop J514, Los Alamos, NM 87545 USA. NR 17 TC 17 Z9 17 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4039 J9 TETRAHEDRON LETT JI Tetrahedron Lett. PD JAN 22 PY 2000 VL 41 IS 4 BP 447 EP 449 DI 10.1016/S0040-4039(99)02090-0 PG 3 WC Chemistry, Organic SC Chemistry GA 277RQ UT WOS:000084947700004 ER PT J AU Lata, R Conway, JF Cheng, NQ Duda, RL Hendrix, RW Wikoff, WR Johnson, JE Tsuruta, H Steven, AC AF Lata, R Conway, JF Cheng, NQ Duda, RL Hendrix, RW Wikoff, WR Johnson, JE Tsuruta, H Steven, AC TI Maturation dynamics of a viral capsid: Visualization of transitional intermediate states SO CELL LA English DT Article ID CRYOELECTRON MICROSCOPY; STRUCTURAL TRANSITIONS; BIOLOGICAL MACROMOLECULES; ELECTRON CRYOMICROSCOPY; CONFORMATIONAL-CHANGES; BACTERIAL-VIRUS; IN-VITRO; PROTEIN; DNA; BACTERIOPHAGE-T4 AB Typical of DNA bacteriophages and herpesviruses, HK97 assembles in two stages: polymerization and maturation. First, capsid protein polymerizes into closed shells; then, these precursors mature into larger, stabler particles. Maturation is initiated by proteolysis, producing a metastable particle primed for expansion-the major structural transition. We induced expansion in vitro by acidic pH and monitored the resulting changes by time-resolved X-ray diffraction and cryo-electron microscopy. The transition, which is not synchronized over the population, proceeds in a series of stochastically triggered subtransitions. Three distinct intermediates were identified, which are comparable to transitional states in protein folding. The intermediates' structures reveal the molecular events occurring during expansion. Integrated into a movie (see Dynamic Visualization below), they show capsid maturation as a dynamic process. C1 NIAMSD, Struct Biol Lab, Bethesda, MD 20892 USA. Univ Pittsburgh, Dept Biol Sci, Pittsburgh, PA 15260 USA. Scripps Res Inst, Dept Mol Biol, La Jolla, CA 92037 USA. Stanford Univ, Stanford Linear Accelerator Ctr, SSRL, Palo Alto, CA 94309 USA. RP Steven, AC (reprint author), NIAMSD, Struct Biol Lab, Bethesda, MD 20892 USA. RI Conway, James/A-2296-2010 OI Conway, James/0000-0002-6581-4748 FU NCRR NIH HHS [P41 RR01209]; NIAID NIH HHS [R01 AI40101]; NIGMS NIH HHS [R01 GM47795] NR 46 TC 109 Z9 110 U1 0 U2 2 PU CELL PRESS PI CAMBRIDGE PA 1050 MASSACHUSETTES AVE, CIRCULATION DEPT, CAMBRIDGE, MA 02138 USA SN 0092-8674 J9 CELL JI Cell PD JAN 21 PY 2000 VL 100 IS 2 BP 253 EP 263 DI 10.1016/S0092-8674(00)81563-9 PG 11 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 277KF UT WOS:000084932200009 PM 10660048 ER PT J AU Samoilova, RI Shubin, AA Bowman, MK Huttermann, J Dikanov, SA AF Samoilova, RI Shubin, AA Bowman, MK Huttermann, J Dikanov, SA TI Observation of two paramagnetic species in electron transfer reactions within cesium modified X and Y zeolites SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ALKALI-MODIFIED ZEOLITES; BASE CATALYSIS; PROBE MOLECULE; IONIC CLUSTERS; BASICITY; OXIDES; SITE; ESR AB Tetrachloro-1,2-benzoquinone (o-chloranyl) has been used as a probe molecule to examine its interaction with catalytically active basic sites of cesium modified X and Y zeolites. Applying CW and pulsed EPR we were able to detect for the first time two paramagnetic species formed in the electron transfer reaction of active sites with o-chloranyl. One species is an anion-radical of o-chloranyl trapped in zeolite cage in the surrounding of alkaline ions. The other one is located on the zeolite lattice and comprises a center with a hole localized on oxygen(s) adjacent to the aluminum carrying about 50% of unpaired spin density. (C) 2000 Elsevier science B.V. All rights reserved. C1 Univ Illinois, Illinois EPR Res Ctr, Urbana, IL 61801 USA. Univ Illinois, Dept Clin Vet Med, Urbana, IL 61801 USA. Russian Acad Sci, Inst Chem Kinet & Combust, Novosibirsk 630090, Russia. Russian Acad Sci, Boreskov Inst Catalysis, Novosibirsk 630090, Russia. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Saarlandes, Fachrichtung Biophys & Phys Grundlagen Med, D-66421 Homburg, Germany. RP Dikanov, SA (reprint author), Univ Illinois, Illinois EPR Res Ctr, 190 MSB,506 S Mathews Av, Urbana, IL 61801 USA. RI Bowman, Michael/F-4265-2011; Shubin, Aleksandr/E-9275-2012 OI Bowman, Michael/0000-0003-3464-9409; Shubin, Aleksandr/0000-0001-7920-3350 NR 27 TC 10 Z9 10 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 21 PY 2000 VL 316 IS 5-6 BP 404 EP 410 DI 10.1016/S0009-2614(99)01342-1 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 277XZ UT WOS:000084960000012 ER PT J AU McLuckey, SA Asano, KG Schaaff, TG Stephenson, JL AF McLuckey, SA Asano, KG Schaaff, TG Stephenson, JL TI Ion trap collisional activation of protonated poly(propylene imine) dendrimers: generations 1-5 SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE poly(propylene imine) dendrimer; quadrupole ion trap; ion/ion proton transfer; ion trap collisional activation ID IONIZATION MASS-SPECTROMETRY; SIZE-EXCLUSION CHROMATOGRAPHY; ELECTROSPRAY-IONIZATION; POLYDISPERSE POLYMERS; INDUCED DISSOCIATION; SYNTHETIC-POLYMERS; STARBURST DENDRIMERS; ENERGY; DISCRIMINATION; PRINCIPLES AB Ions derived from electrospray ionization of poly(propylene imine) dendrimers (generations 1-5, synthesized from a 1,4-diaminobutane core) were subjected to ion trap tandem mass spectrometry. In some cases, ion/ion proton transfer reactions were used to form low charge state parent ions from higher charge state ions generated by electrospray. In addition, ion/ion proton transfer reactions performed on product ions formed by ion trap collisional activation of multiply charged parent ions facilitated interpretation of tandem mass spectrometry (MS/MS) spectra. Almost all of the products derived from dendrimer parent ions could be rationalized based on a set of dissociation processes involving a previously noted intramolecular nucleophilic attack by a nearest-neighbor nitrogen atom on a carbon alpha to a protonation site. For a given protonation site, attack can occur either from the adjacent nitrogen closer to the interior or closer to the exterior of the dendrimer. The processes that lead to the dominant products are highly dependent upon parent ion charge state. Singly charged ions fragment primarily by processes directed by protonation at a diaminobutane nitrogen whereas highly charged parent ions fragment largely by processes directed by protonation closer to the periphery of the dendrimer. MS/MS data for singly charged ions of series of synthesis failure products in the fourth and fifth generation dendrimers were collected. The results show that ion trap tandem mass spectrometry can provide information about the composition of mixtures of isomeric products resulting from side reactions that occur during the course of the multistep syntheses of the dendrimers. The data show, for example, that synthesis failures tend to occur on one side of the dendrimer. (C) 2000 Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP McLuckey, SA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. EM mcluckeysa@ornl.gov RI Stephenson, James/A-9262-2009; McLuckey, Scott/B-2203-2009; Asano, Keiji/L-3164-2016 OI McLuckey, Scott/0000-0002-1648-5570; Asano, Keiji/0000-0003-2254-3586 NR 50 TC 18 Z9 18 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD JAN 21 PY 2000 VL 195 SI SI BP 419 EP 437 DI 10.1016/S1387-3806(99)00201-8 PG 19 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 277HR UT WOS:000084927100038 ER PT J AU Quinones, I Grill, CM Miller, L Guiochon, G AF Quinones, I Grill, CM Miller, L Guiochon, G TI Modeling of separations by closed-loop steady-state recycling chromatography of a racemic pharmaceutical intermediate SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE steady-state recycling; enantiomer separation; pharmaceutical analysis; mathematical modelling ID SIMULATED MOVING-BED; LIQUID-CHROMATOGRAPHY; ADSORPTION-ISOTHERMS; BAND PROFILES; ENANTIOMERS; BINARY; CELLULOSE AB Closed-loop steady-state recycling (SSR) is a cyclic, one-column process that is similar to simulated moving bed (SMB) chromatography in several respects. Both processes are cyclic. In both SMB and SSR, fractions are collected from the leading and trailing portions of the circulating chromatographic profile, and fresh sample is injected into the interior of the profile. However, SMB is a continuous process whereas SSR is a discontinuous, repetitive process. This paper presents a model for the closed-loop SSR process and its experimental validation in a case of practical importance. For this last purpose, we used the closed-loop SSR separation of the enantiomers of a racemic pharmaceutical intermediate. The experimental determination of the competitive adsorption equilibria was performed by frontal analysis in a system composed of a chiral HPLC column as the stationary phase and pure acetonitrile as the mobile phase. All the adsorption data were well correlated by the Langmuir model. The Langmuir model was used to calculate overloaded band profiles corresponding to the separation of racemic mixtures at both analytical and preparative scales. Theoretical band profiles were calculated using the equilibrium-dispersive model. With proper corrections for the contributions of the sources of extra-column band broadening, the model properly predicts the experimental band profiles obtained in the closed-loop SSR setup and demonstrates that a cyclic steady-state develops after the completion of a finite number of cycles. The results also show that the extra-column effects must be accounted for in order to model the closed-loop SSR process accurately. (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. R&S Technol, Narragansett, RI 02882 USA. GD Searle & Co, Skokie, IL 60077 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 32 TC 45 Z9 45 U1 1 U2 9 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 JAN 21 PY 2000 VL 867 IS 1-2 BP 1 EP 21 DI 10.1016/S0021-9673(99)01128-0 PG 21 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 275UK UT WOS:000084838400001 PM 10670707 ER PT J AU Broyles, BS Shalliker, RA Guiochon, G AF Broyles, BS Shalliker, RA Guiochon, G TI Visualization of solute migration in chromatographic columns - Quantitation of the concentration in a migrating zone SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE visualization of solute migration; solute migration; instrumentation; iodine AB The concentration distribution across a zone of iodine migrating along a column made of glass, packed with C-18-bonded silica, and eluted with carbon tetrachloride was derived from a quantitative analysis of the photographs of the zone. The photographs were scanned and turned into digital images. The intensity distributions obtained from the measurement of the grayscale intensity were converted into concentration profiles using a calibration method. This procedure is illustrated and suitable corrections are introduced to account for the transverse variation of the optical path length, as a result of using a cylindrical detector cell (the column itself), and for the refraction of light due to the differences between the refraction indices of the glass wall and the liquids involved. An error analysis is also reported. It shows that the method can reliably produce results with a precision of a few percent, allowing on-column evaluation of column performance and the derivation of the radial distributions of the column efficiency, the migration velocity of the zone, and the sample distribution at the head of the column. (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 Guiochon, G (reprint author), Univ Tennessee, Dept Chem, 611 Buehler Hall, Knoxville, TN 37996 USA. NR 4 TC 15 Z9 15 U1 1 U2 4 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 JAN 21 PY 2000 VL 867 IS 1-2 BP 71 EP 92 DI 10.1016/S0021-9673(99)01085-7 PG 22 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 275UK UT WOS:000084838400005 PM 10670711 ER PT J AU Wellner, A Nellist, PD Palmer, RE Aindow, M Wilcoxon, JP AF Wellner, A Nellist, PD Palmer, RE Aindow, M Wilcoxon, JP TI Orientational and translational ordering of sub-monolayer films of passivated multiply-twinned gold clusters SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID SELF-ORGANIZATION; HIGH-RESOLUTION; SIZE; SUPERLATTICES; PARTICLES; GRAPHITE; SURFACE; NANOPARTICLES; SILVER AB The influence of the substrate on the translational and orientational ordering in sub-monolayer films of passivated multiply-twinned gold clusters has been investigated using high resolution and dark field transmission electron microscopy. Although clear differences were observed in the degree of translational ordering on amorphous carbon and etched silicon substrates, there was no corresponding variation in the crystallographic orientation of the nanocrystal cores. The results demonstrate that the orientation of passivated clusters with multiply-twinned cores is effectively random with respect to both the superlattice and the substrate. C1 Univ Birmingham, Sch Phys & Astron, Nanoscale Phys Res Lab, Birmingham B15 2TT, W Midlands, England. Univ Birmingham, Sch Met & Mat, Birmingham B15 2TT, W Midlands, England. Sandia Natl Labs, Nanostruct & Adv Mat Dept, Albuquerque, NM 87185 USA. RP Wellner, A (reprint author), Univ Birmingham, Sch Phys & Astron, Nanoscale Phys Res Lab, Birmingham B15 2TT, W Midlands, England. RI Palmer, Richard/A-5366-2008; Aindow, Mark/E-5282-2010 OI Palmer, Richard/0000-0001-8728-8083; Aindow, Mark/0000-0001-6617-1409 NR 20 TC 3 Z9 3 U1 1 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD JAN 21 PY 2000 VL 33 IS 2 BP L23 EP L26 DI 10.1088/0022-3727/33/2/104 PG 4 WC Physics, Applied SC Physics GA 281MY UT WOS:000085165800004 ER PT J AU Fowler, JS Wang, GJ Volkow, ND Logan, J Franceschi, D Franceschi, M MacGregor, R Shea, C Garza, V Liu, N Ding, YS AF Fowler, JS Wang, GJ Volkow, ND Logan, J Franceschi, D Franceschi, M MacGregor, R Shea, C Garza, V Liu, N Ding, YS TI Evidence that Ginkgo biloba extract does not inhibit MAO A and B in living human brain SO LIFE SCIENCES LA English DT Article DE Ginkgo biloba; Egb 761; MAO A; MAO B; PET ID POSITRON EMISSION TOMOGRAPHY; MONOAMINE-OXIDASE-A; C-11 L-DEPRENYL; ALTERNATIVE MEDICINE; BINDING; EGB-761; PET; INACTIVATORS; SMOKERS AB Extracts of Ginkgo biloba have been reported to reversibly inhibit both monoamine oxidase (MAO) A and B in rat brain in vitro leading to speculation that MAO inhibition may contribute to some of its central nervous system effects. Here we have used positron emission tomography (PET) to measure the effects of Ginkgo biloba on human brain MAO A and B in 10 subjects treated for 1 month with 120 mg/day of the Ginkgo biloba extract EGb 761, using [C-11]clorgyline and [C-11]L-deprenyl-D2 to measure MAO A and B respectively. A three-compartment model was used to calculate the plasma to brain transfer constant K-1 which is related to blood flow, and lambda k3, a model term which is a function of the concentration of catalytically active MAO molecules. Ginkgo biloba administration did not produce significant changes in brain MAO A or MAO B suggesting that mechanisms other than MAO inhibition need to be considered as mediating some of its CNS effects. (C) 2000 Elsevier Science Inc. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Fowler, JS (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NINDS NIH HHS [NS 15380] NR 24 TC 8 Z9 9 U1 3 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0024-3205 J9 LIFE SCI JI Life Sci. PD JAN 21 PY 2000 VL 66 IS 9 BP PL141 EP PL146 DI 10.1016/S0024-3205(99)00660-8 PG 6 WC Medicine, Research & Experimental; Pharmacology & Pharmacy SC Research & Experimental Medicine; Pharmacology & Pharmacy GA 277GP UT WOS:000084924600011 PM 10698362 ER PT J AU Borer, K Janos, S Palmieri, VG Dezillie, B Li, Z Collins, P Niinikoski, TO Lourenco, C Sonderegger, P Borchi, E Bruzzi, M Pirollo, S Granata, V Pagano, S Chapuy, S Dimcovski, Z Grigoriev, E Bell, W Devine, SRH O'Shea, V Smith, K Berglund, P de Boer, W Hauler, F Heising, S Jungermann, L Casagrande, L Cindro, V Mikuz, M Zavartanik, M da Via, C Esposito, A Konorov, I Paul, S Schmitt, L Buontempo, S D'Ambrosio, N Pagano, S Ruggiero, G Eremin, V Verbitskaya, E AF Borer, K Janos, S Palmieri, VG Dezillie, B Li, Z Collins, P Niinikoski, TO Lourenco, C Sonderegger, P Borchi, E Bruzzi, M Pirollo, S Granata, V Pagano, S Chapuy, S Dimcovski, Z Grigoriev, E Bell, W Devine, SRH O'Shea, V Smith, K Berglund, P de Boer, W Hauler, F Heising, S Jungermann, L Casagrande, L Cindro, V Mikuz, M Zavartanik, M da Via, C Esposito, A Konorov, I Paul, S Schmitt, L Buontempo, S D'Ambrosio, N Pagano, S Ruggiero, G Eremin, V Verbitskaya, E CA RD39 Collaboration TI Charge collection efficiency of irradiated silicon detector operated at cryogenic temperatures SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB The charge collection efficiency (CCE) of heavily irradiated silicon diode detectors was investigated at temperatures between 77 and 200 K. The CCE was found to depend on the radiation dose, bias voltage value and history, temperature, and bias current generated by light. The detector irradiated to the highest fluence 2 x 10(15) n/cm(2) yields a MIP signal of at least 15000 e(-) both at 250 V forward bias voltage, and at 250 V reverse bias voltage in the presence of a light-generated current. The "Lazarus effect" was thus shown to extend to fluences at least ten times higher than was previously studied. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Bern, Lab Hochenergiephys, CH-3012 Bern, Switzerland. Brookhaven Natl Lab, Upton, NY 11973 USA. CERN, CH-1211 Geneva, Switzerland. Univ Florence, Dipartimento Energet, I-50139 Florence, Italy. CNR, Ist Cibernet, I-80072 Arco, Italy. Univ Geneva, Dept Radiol, CH-1211 Geneva, Switzerland. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Helsinki Univ Technol, Low Temp Lab, FI-02150 Espoo, Finland. Univ Karlsruhe, IEKP, D-76128 Karlsruhe, Germany. LIP, P-1000 Lisbon, Portugal. Jozef Stefan Inst, Exp Particle Phys Dep, Ljubljana 1001, Slovenia. Tech Univ Munich, Phys Dept E18, D-85748 Garching, Germany. Univ Naples Federico II, Dipartimento Fis, Naples, Italy. Ist Nazl Fis Nucl, I-80125 Naples, Italy. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. RP Borer, K (reprint author), Univ Bern, Lab Hochenergiephys, Sidlerstarsse 5, CH-3012 Bern, Switzerland. RI Pagano, Sergio/C-5332-2008; Grigoriev, Eugene/K-6650-2013; O'Shea, Val/G-1279-2010; Verbitskaya, Elena/D-1521-2014; Bruzzi, Mara/K-1326-2015; Paul, Stephan/F-7596-2015; Paul, Stephan/K-9237-2016; OI Pagano, Sergio/0000-0001-6894-791X; Grigoriev, Eugene/0000-0001-7235-9715; O'Shea, Val/0000-0001-7183-1205; Bruzzi, Mara/0000-0001-7344-8365; Paul, Stephan/0000-0002-8813-0437; Paul, Stephan/0000-0002-8813-0437; D'Ambrosio, Nicola/0000-0001-9849-8756 NR 11 TC 44 Z9 44 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 21 PY 2000 VL 440 IS 1 BP 5 EP 16 DI 10.1016/S0168-9002(99)00799-8 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 275YM UT WOS:000084847900002 ER PT J AU Taylor, CE Noceti, RP AF Taylor, CE Noceti, RP TI New developments in the photocatalytic conversion of methane to methanol SO CATALYSIS TODAY LA English DT Article; Proceedings Paper CT 5th Chemical Congress of North America CY NOV 11-15, 1997 CL CANCUN, MEXICO SP Engelhard Corp, Mobil Technol Co, Air Prod & Chem Inc, Shell Chem Co, Mexican Acad Catalysis, Mexican Natl Inst Nucl Res, Mexican Petr Inst DE methane conversion; methanol; photocatalysis; tungsten oxide catalysts; hydroxyl radical ID HYDROGEN AB Investigation of direct conversion of methane to transportation fuels has been an on-going effort at FETC for over 14 years. One of our current areas of research is the conversion of methane to methanol, under mild conditions, using light, water, and a semiconductor photocatalyst. Research in our laboratory is directed toward adapting the chemistry developed for photolysis of water to that of methane conversion. The reaction sequence of interest uses visible light, a doped tungsten oxide photocatalyst and an electron transfer molecule to produce a hydroxyl radical. Hydroxyl radical can then react with a methane molecule to produce a methyl radical. In the preferred reaction pathway, the methyl radical then reacts with an additional water molecule to produce methanol and hydrogen. (C)2000 Elsevier Science B.V. All rights reserved. C1 US DOE, Fed Energy Technol Ctr, Pittsburgh, PA 15236 USA. RP Taylor, CE (reprint author), US DOE, Fed Energy Technol Ctr, POB 10940, Pittsburgh, PA 15236 USA. NR 7 TC 48 Z9 57 U1 6 U2 39 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 J9 CATAL TODAY JI Catal. Today PD JAN 20 PY 2000 VL 55 IS 3 BP 259 EP 267 DI 10.1016/S0920-5861(99)00244-8 PG 9 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 276JY UT WOS:000084875700007 ER PT J AU Stoms, DM Hargrove, WW AF Stoms, DM Hargrove, WW TI Potential NDVI as a baseline for monitoring ecosystem functioning SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID CONTERMINOUS UNITED-STATES; VEGETATION INDEX; LAND-COVER; RESOLUTION; PATTERNS; SET AB Baseline data are needed to determine the overall magnitude and direction of change in ecosystem functioning. This letter presents an approach to estimate potential NDVI from environmental variables and training data of actual NDVI in nature reserves. Patterns of deviations of actual NDVI from the baseline generally correspond with land-use types in the western United States. C1 Univ Calif Santa Barbara, Inst Computat Earth Syst Sci, Santa Barbara, CA 93106 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Stoms, DM (reprint author), Univ Calif Santa Barbara, Inst Computat Earth Syst Sci, Santa Barbara, CA 93106 USA. NR 16 TC 35 Z9 41 U1 1 U2 8 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD JAN 20 PY 2000 VL 21 IS 2 BP 401 EP 407 DI 10.1080/014311600210920 PG 7 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA 272ZK UT WOS:000084681200014 ER PT J AU Chacon, L Barnes, DC Knoll, DA Miley, GH AF Chacon, L Barnes, DC Knoll, DA Miley, GH TI An implicit energy-conservative 2D Fokker-Planck algorithm - I. Difference scheme SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE plasma simulation; conservative discretization; energy-conservative Fokker-Planck AB Numerical energy conservation in Fokker-Planck problems requires the energy moment of the Fokker-Planck equation to cancel exactly. However, standard discretization techniques not only do not observe this requirement (thus precluding exact energy conservation), but they also demand very refined meshes to keep the energy error under control. In this paper, a new difference scheme for multidimensional Fokker-Planck problems that improves the numerical cancellation of the energy moment is proposed. Crucial to this new development is the reformulation of the friction term in the Fokker-Planck collision operator using Maxwell stress tensor formalism, As a result, the Fokker-Planck collision operator rakes the form of a double divergence operating on a tensor, which is suitable for particle and energy conservative differencing. Numerical results show that the new discretization scheme improves the cancellation of the energy moment integral over standard approaches by at least an order of magnitude. (C) 2000 Academic Press. C1 Univ Illinois, Fus Studies Lab, Urbana, IL 61801 USA. Univ Calif Los Alamos Natl Lab, XPA, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, XHM, Los Alamos, NM 87545 USA. RP Chacon, L (reprint author), Univ Illinois, Fus Studies Lab, 103 S Goodwin Ave, Urbana, IL 61801 USA. NR 9 TC 22 Z9 23 U1 0 U2 7 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD JAN 20 PY 2000 VL 157 IS 2 BP 618 EP 653 DI 10.1006/jcph.1999.6394 PG 36 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 278MT UT WOS:000084994100007 ER PT J AU Chacon, L Barnes, DC Knoll, DA Miley, GH AF Chacon, L Barnes, DC Knoll, DA Miley, GH TI An implicit energy-conservative 2D Fokker-Planck algorithm - II. Jacobian-free Newton-Krylov solver SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE implicit plasma simulation; energy-conservative Fokker-Planck; non-symmetric systems; preconditioned Krylov methods; multigrid methods ID LINEAR-SYSTEMS AB Energy-conservative implicit integration schemes for the Fokker-Planck transport equation in multidimensional geometries require inverting a dense, non-symmetric matrix (Jacobian), which is very expensive to store and solve using standard solvers. However, these limitations can be overcome with Newton-Krylov iterative techniques, since they can be implemented Jacobian-free (the Jacobian matrix from Newton's algorithm is never formed nor stored to proceed with the iteration), and their convergence can be accelerated by preconditioning the original problem, In this document, the efficient numerical implementation of an implicit energy-conservative scheme for multidimensional Fokker-Planck problems using multigrid-preconditioned Krylov methods is discussed, Results show that multigrid preconditioning is very effective in speeding convergence and decreasing CPU requirements, particularly in fine meshes. The solver is demonstrated on grids up to 128 x 128 points in a 2D cylindrical velocity space (upsilon(r), upsilon(p)) with implicit time steps of the order of the collisional time scale of the problem, tau. The method preserves particles exactly, and energy conservation is improved over alternative approaches, particularly in coarse meshes, Typical errors in the total energy over a rime period of 10 tau remain below a percent. (C) 2000 Academic Press. C1 Univ Illinois, Fus Studies Lab, Urbana, IL 61801 USA. Univ Calif Los Alamos Natl Lab, XPA, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, XHM, Los Alamos, NM 87545 USA. RP Chacon, L (reprint author), Univ Illinois, Fus Studies Lab, 103 Goodwin Ave, Urbana, IL 61801 USA. NR 19 TC 23 Z9 24 U1 0 U2 3 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD JAN 20 PY 2000 VL 157 IS 2 BP 654 EP 682 DI 10.1006/jcph.1999.6395 PG 29 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 278MT UT WOS:000084994100008 ER PT J AU Rasch, PJ Barth, MC Kiehl, JT Schwartz, SE Benkovitz, CM AF Rasch, PJ Barth, MC Kiehl, JT Schwartz, SE Benkovitz, CM TI A description of the global sulfur cycle and its controlling processes in the National Center for Atmospheric Research Community Climate Model, Version 3 SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SULFATE DISTRIBUTION; 3-DIMENSIONAL MODEL; AEROSOLS; SIMULATION AB We examine the balance between processes that contribute to the global and regional distributions of sulfate aerosol in the Earth's atmosphere using a set of simulations from the National Center for Atmospheric Research Community Climate Model, Version 3. The analysis suggests that the seasonal cycle of SO2 and SO42- are controlled by a complex Db 4 interplay between transport, chemistry and deposition processes. The seasonal cycle of these species is not strongly controlled by temporal variations in emissions but by seasonal variations in volume of air processed by clouds, mass of liquid water serving as a site for aqueous chemistry, amount of oxidant available for the conversion from SO2 to SO42-, vertical transport processes, and deposition. A tagging of the sulfate by emission region (Europe, North America, Asia, and rest of world [ROW]), chemical pathway (gaseous versus in-cloud), and type of emissions (anthropogenic versus biogenic) is used to differentiate the balance of processes controlling the production and loading from this material. Significant differences exist in the destiny of SO2 molecules emitted from the several regions. An SO2, molecule emitted from the ROW source region has a much greater potential to form sulfate than one emitted from, for example, Europe. A greater fraction of the SO2 molecules is oxidized that originate from ROW compared with other areas, and once formed, the sulfate has a longer residence time (that is, it is not readily scavenged). The yield of sulfate from ROW sources of SO2 is a factor of 4 higher than that of Europe. A substantially higher fraction of the SO2 emitted over Europe is oxidized to sulfate through the ozone pathway compared to other regions. The analysis suggests that there are significant differences in the vertical distribution, and horizontal extent, of the propagation of sulfate emitted from the several source regions. Sulfate from Asian source regions reaches the farthest from its point of origin and makes a significant contribution to burdens in both hemispheres, primarily from plumes reaching out in the upper troposphere. Sulfate from other source regions tends to remain trapped in their hemisphere of origin. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Rasch, PJ (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. EM pjr@ucar.edu RI Schwartz, Stephen/C-2729-2008 OI Schwartz, Stephen/0000-0001-6288-310X NR 28 TC 123 Z9 127 U1 0 U2 22 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 JAN 20 PY 2000 VL 105 IS D1 BP 1367 EP 1385 DI 10.1029/1999JD900777 PG 19 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 276BW UT WOS:000084856600005 ER PT J AU Barth, MC Rasch, PJ Kiehl, JT Benkovitz, CM Schwartz, SE AF Barth, MC Rasch, PJ Kiehl, JT Benkovitz, CM Schwartz, SE TI Sulfur chemistry in the National Center for Atmospheric Research Community Climate Model: Description, evaluation, features, and sensitivity to aqueous chemistry SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GLOBAL SULFATE DISTRIBUTION; ACID DEPOSITION MODEL; DIMETHYL SULFIDE; HYDROGEN-PEROXIDE; STRATOSPHERIC AEROSOL; 3-DIMENSIONAL MODEL; NORTH-ATLANTIC; BOUNDARY-LAYER; OPTICAL DEPTH; AIR-POLLUTION AB Sulfur chemistry has been incorporated in the National Center for Atmospheric Research Community Climate Model in an internally consistent manner with other parameterizations in the model. The model predicts mixing Processes that control the mixing ratio of these species include the emissions of DMS and SO2, transport of each species, gas- and aqueous-phase chemistry, wet deposition, and dry deposition of species. Modeled concentrations agree quite well with observations for DMS and H2O2 fairly well for SO2, and not as well for SO42- The modeled SO42- tends to underestimate observed SO42- at the surface and overestimate observations in the upper troposphere. The SO2 and SO42- species were tagged according to the chemical production pathway and whether the sulfur was of anthropogenic or biogenic origin. Although aqueous-phase reactions in cloud accounted for 81% of the sulfate production rate, only similar to 50-60% of the sulfate burden in the troposphere was derived from cloud chemistry. Because cloud chemistry is an important source of sulfate in the troposphere, the importance of H2O2 concentrations and pH values was investigated. When prescribing H2O2 concentrations to clear-sky values instead of predicting H2O2, the global-averaged, annual-averaged in-cloud production of sulfate increased. Setting the pH of the drops to 4.5 also increased the in-cloud production of sulfate. In both sensitivity simulations, the increased in-cloud production of sulfate decreased the burden of sulfate because less SO2 was available for gas-phase conversion, which contributes more efficiently to the tropospheric sulfate burden than does aqueous-phase conversion. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Barth, MC (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. EM barthm@ucar.edu RI Schwartz, Stephen/C-2729-2008 OI Schwartz, Stephen/0000-0001-6288-310X NR 80 TC 158 Z9 166 U1 0 U2 25 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 JAN 20 PY 2000 VL 105 IS D1 BP 1387 EP 1415 DI 10.1029/1999JD900773 PG 29 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 276BW UT WOS:000084856600006 ER PT J AU Johnston, H Kinnison, D AF Johnston, H Kinnison, D TI Comment on "Methane photooxidation in the atmosphere: Contrast between two methods of analysis" by Harold Johnston and Douglas Kinnison - Reply SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Editorial Material ID TROPOSPHERIC OZONE; CHEMISTRY; NITROGEN C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Johnston, H (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM johnston@cchem.berkeley.edu NR 10 TC 2 Z9 2 U1 0 U2 1 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 JAN 20 PY 2000 VL 105 IS D1 BP 1435 EP 1439 DI 10.1029/1999JD900432 PG 5 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 276BW UT WOS:000084856600010 ER PT J AU Zheng, H Maness, PC Blake, DM Wolfrum, EJ Smolinski, SL Jacoby, WA AF Zheng, H Maness, PC Blake, DM Wolfrum, EJ Smolinski, SL Jacoby, WA TI Bactericidal mode of titanium dioxide photocatalysis SO JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY LA English DT Article DE TiO2 photocatalysis; bactericidal mode; permeability; ONPG assay ID ESCHERICHIA-COLI; STERILIZATION RATES; MICROBIAL-CELLS; TIO2; INACTIVATION; WATER; OXIDATION; RADIATION; EXPOSURE; CATALYST AB When exposed to near-UV light, titanium dioxide (TiO2) exhibits a strong bactericidal activity. However, the killing mechanism(s) underlying the TiO2 photocatalytic reaction is not yet well understood. The aim of the present study is to investigate the cellular damage sites and their contribution to cell death. A sensitive approach using o-nitrophenol beta-D-galactopyranosideside (ONPG) as the probe and Escherichia coli as model cells has been developed. This approach is used to illustrate damages to both the cell envelope and intracellular components caused by TiO2 photocatalytic reaction. Treatment of E. coli with TiO2 and near-UV light resulted in an immediate increase in permeability to small molecules such as ONPG, and the leakage of large molecules such as beta-D-galactosidase after 20 min. Kinetic data showed that cell wall damage took place in less than 20 min, followed by a progressive damage of cytoplasmic membrane and intracellular components. The results from the ONPG assay correlated well with the loss of cell viability. Cell wall damage followed by cytoplasmic membrane damage leading to a direct intracellular attack has therefore been proposed as the sequence of events when microorganisms undergo TiO2 photocatalytic attack. It has been found that smaller TiO2 particles cause quicker intracellular damage. Evidence has been obtained that indicated that the TiO2 photocatalytic reaction results in continued bactericidal activity after the UV illumination terminates. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Missouri, Dept Chem Engn, Columbia, MO 65211 USA. RP Zheng, H (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 38 TC 28 Z9 41 U1 4 U2 37 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 1010-6030 J9 J PHOTOCH PHOTOBIO A JI J. Photochem. Photobiol. A-Chem. PD JAN 20 PY 2000 VL 130 IS 2-3 BP 163 EP 170 PG 8 WC Chemistry, Physical SC Chemistry GA 276KL UT WOS:000084876900012 ER PT J AU Hjelm, RP Schteingart, CD Hofmann, AF Thiyagarajan, P AF Hjelm, RP Schteingart, CD Hofmann, AF Thiyagarajan, P TI Structure of conjugated bile salt-fatty acid-monoglyceride mixed colloids: Studies by small-angle neutron scattering SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ELASTIC LIGHT-SCATTERING; TRANSMISSION ELECTRON-MICROSCOPY; VESICLE-MICELLE TRANSITION; BILIARY LIPID SYSTEMS; MAXIMUM-ENTROPY; IONIC MICELLES; SELF-DIFFUSION; LECITHIN; PHOSPHATIDYLCHOLINE; MIXTURES AB The structures of particles found in isotropic phases of mixed surfactant systems consisting of conjugated bile salts and fatty lipids were assessed using small-angle neutron scattering. The conjugated bile salts were either cholylglycine or chenodeoxycholylglycine. The fatty lipids were mixtures of oleate and oleic acid either alone or with monoolein. The scattering data suggested that both particle interactions and polydispersity must be modeled in these systems. Particle interactions were modeled using the reduced mean spherical approximation and the decoupling approximation. Maximum entropy was used to characterize the polydispersity. A self-consistent analysis of the scattering was arrived at by making an initial estimate of particle size and shape using derivative-log and Guinier analysis and refining the estimates by analyzing the particle interactions and polydispersity and iterating. The scattering at high total lipid concentrations was consistent with globular mixed micelles with repulsive electrostatic interactions. The globular mixed micelles in these systems were similar in size and shape to those observed previously in conjugated bile salt mixtures with either egg yolk phosphatidylcholine or monoolein. Solutions of cholylglycine with monoolein and oleate/oleic acid underwent a transition to vesicles at lower concentrations. This behavior was similar to those observed in conjugated bile salts with either egg yolk phosphatidylcholine or monoolein. Cholylglycine mixtures with oleate/oleic showed somewhat different behavior at lower concentrations, since there was also evidence for coexistence of elongated and tabletlike micelles. Despite these differences, there were sufficient similarities in the particle morphologies of these and other conjugated bile salt-fatty lipid systems to suggest a common mode of self-assembly. These solutions are models for bile in the bilary system and intestine content during triglyceride digestion; the common themes of self-assembly have implications for the physiology of lipid solubilization in bile as well as intestinal absorption of dietary lipids. C1 Los Alamos Natl Lab, Los Alamos Neutron Sci Ctr, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. Univ Calif San Diego, Sch Med, Dept Med, La Jolla, CA 92093 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Hjelm, RP (reprint author), Los Alamos Natl Lab, Los Alamos Neutron Sci Ctr, Manuel Lujan Jr Neutron Scattering Ctr, POB 1663, Los Alamos, NM 87545 USA. EM Hjelm@lanl.gov RI Lujan Center, LANL/G-4896-2012 NR 56 TC 43 Z9 43 U1 1 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD JAN 20 PY 2000 VL 104 IS 2 BP 197 EP 211 DI 10.1021/jp992157n PG 15 WC Chemistry, Physical SC Chemistry GA 278TT UT WOS:000085005600005 ER PT J AU Click, CA Assink, RA Brinker, CJ Naik, SJ AF Click, CA Assink, RA Brinker, CJ Naik, SJ TI An investigation of molecular templating in amorphous silicas by cross-polarization NMR spectroscopy SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID CP-MAS NMR; MEMBRANES; PROSPECTS; DYNAMICS; SIEVE AB The precise pore sizes defined by crystalline zeolite lattices have led to intensive research on zeolite membranes. Unfortunately, zeolites have been extremely difficult to prepare in a defect-free thin film form needed for membrane flux and selectivity. We introduced tetrapropylammonium (TPA), a structure-directing agent for zeolite ZSM-5, into a silica sol and exploit the development of high solvation stresses to create templated amorphous silicas with pore apertures similar in size to those of ZSM-5. Silicon and carbon NMR experiments were performed to evaluate the efficacy of our templating approach. The Si-29 NMR spectrum of the silica matrix was observed by an intermolecular cross-polarization experiment involving the H-1 nuclei of TPA and the Si-29 nuclei in the silica matrix. The efficiency of the cross-polarization interaction was used to investigate the degree to which the matrix formed a tight cage surrounding the template molecule. Bulk xerogels, prepared by gelation and slow drying of the corresponding sols, exhibited only weak interactions between the two sets of nuclei. Thin film xerogels, where drying stresses are greater, exhibited significantly increased interactions. Intramolecular cross-polarization experiments between the H-1 and C-13 nuclei of the template molecule demonstrated that much of the increased efficiency was a result of reduced rotational mobility of the TPA molecule. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Missouri, Rolla, MO 65401 USA. Univ New Mexico, Albuquerque, NM 87131 USA. RP Assink, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 5 Z9 5 U1 0 U2 2 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 JAN 20 PY 2000 VL 104 IS 2 BP 233 EP 236 DI 10.1021/jp992762q PG 4 WC Chemistry, Physical SC Chemistry GA 278TT UT WOS:000085005600009 ER PT J AU Rodriguez, JA Jirsak, T Dvorak, J Sambasivan, S Fischer, D AF Rodriguez, JA Jirsak, T Dvorak, J Sambasivan, S Fischer, D TI Reaction of NO2 with Zn and ZnO: Photoemission, XANES, and density functional studies on the formation of NO3 SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID TRANSITION-METAL COMPLEXES; NITROGEN-DIOXIDE; NITRIC-OXIDE; ZINC-OXIDE; INTERMEDIATE NEGLECT; MOLECULAR ADSORPTION; ELECTRONIC-STRUCTURE; AB-INITIO; SURFACES; CO AB Synchrotron-based high-resolution photoemission and X-ray absorption near-edge spectroscopy (XANES) have been used to study the interaction of NO2 with polycrystalline surfaces of metallic zinc and zinc oxide. NO2 exhibits a complex chemistry on metallic zinc. After adsorbing nitrogen dioxide, N, O, NO, NO2, and NO3 are present on the surface of the metal. At room temperature the NO2 molecule mainly dissociates into O adatoms and gaseous NO, whereas at low temperatures (< 250 K) chemisorbed NO2 and NO3 dominate on the surface. NO2 is a very good oxidizing agent for preparing ZnO from metallic zinc. Zn reacts more vigorously with NO2 than metals, such as Rh, Pd, or Pt which are typical catalysts for the removal of NOx molecules (DeNO(x) process). At 300 K, the main product of the reaction of NO2 with polycrystalline ZnO is adsorbed NO3 with little NO2 or NO present on the surface of the oxide. No evidence was found for the full decomposition of the NO2 molecule (i.e., no NO2 -> N + 2O). The results of density functional (DF-GGA) calculations for the adsorption of NO2 on a six-layer slab of ZnO, or INDO/S calculations for NO2 on a Zn37O37 cluster, show stronger chemisorption bonds on (0001) Zn-terminated terraces than on (000 (1) over bar) O-terminated terraces. The Zn -> NO2 interactions on ZnO are strong and the Zn sites probably get oxidized and nitrated as a result of them. It appears that NO2 is very efficient for fully oxidizing metal centers that are missing O neighbors in oxide surfaces. On zinc oxide, the nitrate species are stable up to temperatures near 700 K. ZnO can be useful as a sorbent in DeNO(x) operations. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. Natl Inst Stand & Technol, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 88 TC 284 Z9 294 U1 8 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 JAN 20 PY 2000 VL 104 IS 2 BP 319 EP 328 DI 10.1021/jp993224g PG 10 WC Chemistry, Physical SC Chemistry GA 278TT UT WOS:000085005600020 ER PT J AU Yan, YF Pennycook, SJ AF Yan, YF Pennycook, SJ TI Alloys - Atomic structure of the quasicrystal Al72Ni20Co8 SO NATURE LA English DT Article ID TILINGS C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Yan, YF (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 6 TC 9 Z9 9 U1 0 U2 17 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 20 PY 2000 VL 403 IS 6767 BP 266 EP 267 DI 10.1038/35002251 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 276VU UT WOS:000084899700038 ER PT J AU Kandus, A Calzetta, EA Mazzitelli, FD Wagner, CEM AF Kandus, A Calzetta, EA Mazzitelli, FD Wagner, CEM TI Cosmological magnetic fields from gauge-mediated supersymmetry-breaking models SO PHYSICS LETTERS B LA English DT Article ID BIG-BANG NUCLEOSYNTHESIS; LOW-ENERGY SUPERSYMMETRY; PHASE-TRANSITIONS; CONSTRAINTS; INFLATION; UNIVERSE; TECHNICOLOR; SIGNATURES; GENERATION; SYSTEMS AB We study the generation of primordial magnetic fields, coherent over cosmologically interesting scales, by gravitational creation of charged scalar particles during the reheating period. We show that magnetic fields consistent with those detected by observation may be obtained if the particle mean life tau(s) is in the range 10(-14) s less than or similar to tau(s) less than or similar to 10(-7) s. We apply this mechanism to minimal gauge-mediated supersymmetry-breaking models, in the case in which the lightest stau <(tau)over tilde>(1) is the next-to-lightest supersymmetric particle. We show that, for a large range of phenomenologically acceptable values of the supersymmetry-breaking scale root F, the generated primordial magnetic field can be strong enough to seed the galactic dynamo. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Buenos Aires, Fac Ciencias Exactas & Nat, Dept Fis, RA-1428 Buenos Aires, DF, Argentina. CERN, Div Theory, CH-1211 Geneva 23, Switzerland. Argonne Natl Lab, High Energy Div, Argonne, IL 60439 USA. RP Kandus, A (reprint author), Univ Buenos Aires, Fac Ciencias Exactas & Nat, Dept Fis, Ciudad Univ, RA-1428 Buenos Aires, DF, Argentina. NR 53 TC 44 Z9 44 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 JAN 20 PY 2000 VL 472 IS 3-4 BP 287 EP 294 DI 10.1016/S0370-2693(99)01389-1 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 280VE UT WOS:000085123800010 ER PT J AU Cline, J Grojean, C Servant, G AF Cline, J Grojean, C Servant, G TI Inflating intersecting branes and remarks on the hierarchy problem SO PHYSICS LETTERS B LA English DT Article ID DIMENSIONS; TEV AB Wr generalize solutions of Einstein's equations for intersecting branes in higher dimensional spacetimes to the nonstatic case, modeling an expanding universe. The relation between the Hubble rate, the brane tensions, and the bulk cosmological constant is similar to the case of a single 3-brane in a 5-dimensional spacetime. However, because the bulk inflates as well as the branes, this class of solutions suffers from Newton's constant tending toward zero on the TeV brane, where the Randall-Sundrum mechanism should solve the weak scale hierarchy problem. The strength of gravity remains constant on the Planck brane, however. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. CEA, Serv Phys Theor, F-91191 Gif Sur Yvette, France. RP Cline, J (reprint author), McGill Univ, Dept Phys, 3600 Univ St, Montreal, PQ H3A 2T8, Canada. OI grojean, christophe/0000-0002-7196-7361 NR 29 TC 30 Z9 30 U1 0 U2 0 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 JAN 20 PY 2000 VL 472 IS 3-4 BP 302 EP 308 DI 10.1016/S0370-2693(99)01471-9 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 280VE UT WOS:000085123800012 ER PT J AU Cernota, P Rider, K Yoon, HA Salmeron, M Somorjai, G AF Cernota, P Rider, K Yoon, HA Salmeron, M Somorjai, G TI Dense structures formed by CO on Rh(111)studied by scanning tunneling microscopy SO SURFACE SCIENCE LA English DT Article DE carbon dioxide; chemisorption; low index single crystal surfaces; rhodium; scanning tunneling microscopy ID CRYSTAL-SURFACE; LEED; SPECTROSCOPY; ADSORPTION AB Scanning tunneling microscopy (STM) has been used to study the chemisorption of CO on a Rh(lll) single crystal surface at room temperature at coverage greater than or equal to 0.5 ML. A background pressure of CO was maintained during imaging. The structures observed include a (2 x 1) and two forms of (root 7 x root 5)R19 degrees that had not been previously observed. In contrast to the low coverage regime, above 3/7 ML, CO occupies both top and three-fold hollow adsorption sites. The highest coverage structure, (2 x 2)-3CO, was found to be stable under CO pressures of at least 700 Torr. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Salmeron, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 12 TC 33 Z9 33 U1 3 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JAN 20 PY 2000 VL 445 IS 2-3 BP 249 EP 255 DI 10.1016/S0039-6028(99)01073-0 PG 7 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 280CW UT WOS:000085085500014 ER PT J AU Snyder, JA Jaffe, JE Lin, ZJ Hess, AC Gutowski, M AF Snyder, JA Jaffe, JE Lin, ZJ Hess, AC Gutowski, M TI Adsorption of CO on MgO supported alkali monolayers: a periodic density functional local density approximation and generalized gradient approximation study SO SURFACE SCIENCE LA English DT Article DE adatoms; alkali metal monolayers; carbon monoxide; catalysis; chemisorption; density functional calculations; magnesium oxide ID HARTREE-FOCK; OXIDATIVE DIMERIZATION; HELIUM DIFFRACTION; OXIDE CATALYSTS; SURFACE; METAL; MAGNESIUM; METHANE; ENERGETICS; MGO(100) AB The adsorption of CO on the MgO supported Na and K monolayers was investigated using a periodic density functional method. We found that the cooperative (non-pairwise) interaction present among the three constituents of the complex system, the MgO slab, the alkali metal monolayer, and the CO monolayer, is very small and that the only role of MgO is to support the alkali metal monolayer. Our calculations predict weakening of the CO bond due to the presence of the alkali metal monolayer, reflected by an elongation of the CO bond by 0.005 Angstrom and a redshift of the CO stretching frequency by ca. 30 cm(-1) in comparison with the corresponding gas phase values. The calculated density of states for the Mg...M, CO, and Mg...M...CO systems (M =Na, K) indicates that the electron transfer from the valence band of the alkali metal to the antibonding pi* orbital of CO is the source of the CO bond weakening. Our estimate of the binding energy for CO on the MgO...M substrate is 5.1 and 5.0 kcal/mol for M = Na and K, respectively. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Dept Mat Sci, Richland, WA 99352 USA. Numtek, Vancouver, BC V5N 1Y9, Canada. Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. RP Gutowski, M (reprint author), Pacific NW Natl Lab, Dept Mat Sci, Richland, WA 99352 USA. RI Lin, Zijing/D-4050-2009 NR 33 TC 17 Z9 17 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JAN 20 PY 2000 VL 445 IS 2-3 BP 495 EP 505 DI 10.1016/S0039-6028(99)01120-6 PG 11 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 280CW UT WOS:000085085500037 ER PT J AU Li, ZZ Wu, RL Michalczyk, R Dunlap, RB Odom, JD Silks, LAP AF Li, ZZ Wu, RL Michalczyk, R Dunlap, RB Odom, JD Silks, LAP TI Stereoselectivity in aldol reactions of chiral N-acyl selones SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID MAGNETIC-RESONANCE SPECTROSCOPY; SE-77 NMR-SPECTROSCOPY; OXAZOLIDINE-2-SELONES; CENTERS; QUANTITATION; ADDITIONS; ACID C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. RP Silks, LAP (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, MS E529, Los Alamos, NM 87545 USA. OI Michalczyk, Ryszard/0000-0001-8839-6473 NR 27 TC 38 Z9 38 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 19 PY 2000 VL 122 IS 2 BP 386 EP 387 DI 10.1021/ja992702y PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 278PW UT WOS:000084999000023 ER PT J AU Weik, M Ravelli, RBG Kryger, G McSweeney, S Raves, ML Harel, M Gros, P Silman, I Kroon, J Sussman, JL AF Weik, M Ravelli, RBG Kryger, G McSweeney, S Raves, ML Harel, M Gros, P Silman, I Kroon, J Sussman, JL TI Specific chemical and structural damage to proteins produced by synchrotron radiation SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID BIOLOGICAL MACROMOLECULES; PROGRAM; ACETYLCHOLINESTERASE; DIFFRACTION; PHASES; ERRORS; MAPS; DNA AB Radiation damage is an inherent problem in x-ray crystallography. It usually is presumed to be nonspecific and manifested as a gradual decay in the overall quality of data obtained for a given crystal as data collection proceeds. Based on third-generation synchrotron x-ray data, collected at cryogenic temperatures, we show for the enzymes Torpedo californica acetylcholinesterase and hen egg white lysozyme that synchrotron radiation also can cause highly specific damage. Disulfide bridges break, and carboxyl groups of acidic residues lose their definition. Highly exposed carboxyls, and those in the active site of both enzymes, appear particularly susceptible. The catalytic triad residue, His-440, in acetylcholinesterase, also appears to be much more sensitive to radiation damage than other histidine residues. Our findings have direct practical implications for routine x-ray data collection at high-energy synchrotron sources. Furthermore, they provide a direct approach for studying the radiation chemistry of proteins and nucleic acids at a detailed, structural level and also may yield information concerning putative "weak links" in a given biological macromolecule, which may be of structural and functional significance. C1 Weizmann Inst Sci, Dept Biol Struct, IL-76100 Rehovot, Israel. Univ Utrecht, Dept Crystal & Struct Chem, NL-3584 CH Utrecht, Netherlands. Univ Utrecht, Dept NMR Spectroscopy, Bijvoet Ctr Biomol Res, NL-3584 CH Utrecht, Netherlands. European Mol Biol Lab Outstn, F-38042 Grenoble, France. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Sussman, JL (reprint author), Weizmann Inst Sci, Dept Biol Struct, IL-76100 Rehovot, Israel. RI Gros, Piet/I-5569-2016; OI Gros, Piet/0000-0002-7782-2585; Sussman, Joel/0000-0003-0306-3878 NR 39 TC 353 Z9 355 U1 2 U2 29 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 JAN 18 PY 2000 VL 97 IS 2 BP 623 EP 628 DI 10.1073/pnas.97.2.623 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 276HX UT WOS:000084873100021 PM 10639129 ER PT J AU Hegmann, FA Williams, JB Cole, B Sherwin, MS Beeman, JW Haller, EE AF Hegmann, FA Williams, JB Cole, B Sherwin, MS Beeman, JW Haller, EE TI Time-resolved photoresponse of a gallium-doped germanium photoconductor using a variable pulse-width terahertz source SO APPLIED PHYSICS LETTERS LA English DT Article ID FAR-INFRARED PHOTOCONDUCTORS; GENERATION; RADIATION AB Picosecond to nanosecond-wide terahertz pulses are used to study the fast photoresponse of a gallium-doped germanium (Ge:Ga) photoconductor operating at 4.2 K. A recombination time of about 2 ns is observed in the time-resolved photoresponse. Laser-activated semiconductor reflection switches are used to "slice" the variable-width terahertz pulses from the quasicontinuous-wave output of a free-electron laser. (C) 2000 American Institute of Physics. [S0003-6951(00)02703-0]. C1 Univ Calif Santa Barbara, Dept Phys, Quantum Inst, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Ctr Terahertz Sci & Technol, Santa Barbara, CA 93106 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. RP Sherwin, MS (reprint author), Univ Calif Santa Barbara, Dept Phys, Quantum Inst, Santa Barbara, CA 93106 USA. NR 13 TC 23 Z9 23 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 17 PY 2000 VL 76 IS 3 BP 262 EP 264 DI 10.1063/1.125741 PG 3 WC Physics, Applied SC Physics GA 272WZ UT WOS:000084675100004 ER PT J AU Park, J Henins, I Herrmann, HW Selwyn, GS Jeong, JY Hicks, RF Shim, D Chang, CS AF Park, J Henins, I Herrmann, HW Selwyn, GS Jeong, JY Hicks, RF Shim, D Chang, CS TI An atmospheric pressure plasma source SO APPLIED PHYSICS LETTERS LA English DT Article ID NUMERICAL-MODEL; JET AB An atmospheric pressure plasma source operated by radio frequency power has been developed. This source produces a unique discharge that is volumetric and homogeneous at atmospheric pressure with a gas temperature below 300 degrees C. It also produces a large quantity of oxygen atoms, similar to 5 x 10(15) cm(-3), which has important value for materials applications. A theoretical model shows electron densities of 0.2-2 x 10(11) cm(-3) and characteristic electron energies of 2-4 eV for helium discharges at a power level of 3-30 W cm(-3). (C) 2000 American Institute of Physics. [S0003-6951(00)01303-6]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Los Angeles, Dept Chem Engn, Los Angeles, CA 90095 USA. NYU, New York, NY 10012 USA. Korea Adv Inst Sci & Technol, Taejon 305701, South Korea. RP Park, J (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 18 TC 177 Z9 184 U1 2 U2 44 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 17 PY 2000 VL 76 IS 3 BP 288 EP 290 DI 10.1063/1.125724 PG 3 WC Physics, Applied SC Physics GA 272WZ UT WOS:000084675100013 ER PT J AU Zhang, X Solak, H Cerrina, F Lai, B Cai, Z Ilinski, P Legnini, D Rodrigues, W AF Zhang, X Solak, H Cerrina, F Lai, B Cai, Z Ilinski, P Legnini, D Rodrigues, W TI X-ray microdiffraction study of Cu interconnects SO APPLIED PHYSICS LETTERS LA English DT Article ID ELECTROMIGRATION-INDUCED STRESS; CONFINED METAL LINES; THIN-FILMS; COPPER; TITANIUM; MICROSTRUCTURE; METALLIZATION; DIFFUSION; EVOLUTION AB We have used x-ray microdiffraction to study the local structure and strain variation of copper interconnects. Different types of local microstructures have been found in different samples. Our data show that the Ti adhesion layer has a very dramatic effect on Cu microstructure. Strain measurement was conducted before and after electromigration test, Cu fluorescence was used to find the mass variations around voids and hillocks, and x-ray microdiffraction was used to measure the strain change around that interested region. (C) 2000 American Institute of Physics. [S0003-6951(00)03903-6]. C1 Univ Wisconsin, Dept Elect & Comp Engn, Madison, WI 53706 USA. Univ Wisconsin, Ctr Nanotechnol, Madison, WI 53706 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Zhang, X (reprint author), Univ Wisconsin, Dept Elect & Comp Engn, 1415 Johnson Dr, Madison, WI 53706 USA. NR 24 TC 14 Z9 14 U1 2 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 17 PY 2000 VL 76 IS 3 BP 315 EP 317 DI 10.1063/1.125731 PG 3 WC Physics, Applied SC Physics GA 272WZ UT WOS:000084675100022 ER PT J AU Ashby, CIH Zavadil, KR Baca, AG Chang, PC Hammons, BE Hafich, MJ AF Ashby, CIH Zavadil, KR Baca, AG Chang, PC Hammons, BE Hafich, MJ TI Metal-sulfur-based air-stable passivation of GaAs with very low surface-state densities SO APPLIED PHYSICS LETTERS LA English DT Article ID HETEROJUNCTION BIPOLAR-TRANSISTORS; V COMPOUND SEMICONDUCTORS; ULTRAVIOLET PHOTOSULFIDATION; GAIN AB An air-stable electronic surface passivation for GaAs and other III-V compound semiconductors that employs sulfur and a suitable metal ion, e.g., Zn, and that is robust towards plasma dielectric deposition has been developed. Initial improvements in photoluminescence are twice that of S-only treatments and have been preserved for > 11 months with SiOxNy dielectric encapsulation. Photoluminescence and x-ray photoelectron spectroscopies indicate that the passivation consists of two major components with one being stable for > 2 years in air. This process improves heterojunction bipolar transistor current gain for both large and small area devices. (C) 2000 American Institute of Physics. [S0003-6951(00)00803-2]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ashby, CIH (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 14 TC 7 Z9 7 U1 2 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 17 PY 2000 VL 76 IS 3 BP 327 EP 329 DI 10.1063/1.125734 PG 3 WC Physics, Applied SC Physics GA 272WZ UT WOS:000084675100026 ER PT J AU Wang, LW Williamson, AJ Zunger, A Jiang, H Singh, J AF Wang, LW Williamson, AJ Zunger, A Jiang, H Singh, J TI Comparison of the k center dot p and direct diagonalization approaches to the electronic structure of InAs/GaAs quantum dots SO APPLIED PHYSICS LETTERS LA English DT Article ID BAND AB We present a comparison of the 8-band k.p and empirical pseudopotential approaches to describing the electronic structure of pyramidal InAs/GaAs self-assembled quantum dots. We find a generally good agreement between the two methods. The most significant differences found in the k.p calculation are (i) a reduced splitting of the electron p states (3 vs 24 meV), (ii) an incorrect in-plane polarization ratio for electron-hole dipole transitions (0.97 vs 1.24), and (iii) an over confinement of both electron (48 meV) and hole states (52 meV), resulting in a band gap error of 100 meV. We introduce a "linear combination of bulk bands" technique which produces results similar to a full direct diagonalization pseudopotential calculation, at a cost similar to the k.p method. (C) 2000 American Institute of Physics. [S0003-6951(00)01903-3]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Michigan, Dept Elect Engn & Comp Sci, Ann Arbor, MI 48109 USA. RP Wang, LW (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Zunger, Alex/A-6733-2013 NR 26 TC 81 Z9 81 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 17 PY 2000 VL 76 IS 3 BP 339 EP 341 DI 10.1063/1.125747 PG 3 WC Physics, Applied SC Physics GA 272WZ UT WOS:000084675100030 ER PT J AU Ames, BN Gold, LS AF Ames, BN Gold, LS TI Paracelsus to parascience: the environmental cancer distraction SO MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS LA English DT Article DE cancer prevention; micronutrients; natural chemicals; mutagens; cancer mechanism; animal cancer tests ID LOW-INCOME HOUSEHOLDS; HEPATOCELLULAR PROLIFERATION; HEMATOLOGICAL FINDINGS; CHEMICAL CARCINOGENS; HOMOCYSTEINE STATUS; RODENT CARCINOGENS; OXIDATIVE EVENTS; DNA OXIDATION; IRON STATUS; FOLIC-ACID AB Entering a new millennium seems a good time to challenge some old ideas, which in our view are implausible, have Little supportive evidence, and might best be left behind. In this essay, we summarize a decade of work, raising four issues that involve toxicology, nutrition, public health, and government regulatory policy. (a) Paracelsus or parascience: the close (trace) makes the poison. Half of all chemicals, whether natural or synthetic, are positive in high-dose rodent cancer tests. These results are unlikely to be relevant at the low doses of human exposure. (b) Even Rachel Carson was made of chemicals: natural vs. synthetic chemicals. Human exposure to naturally occurring rodent carcinogens is ubiquitous, and dwarfs the general public's exposure to synthetic rodent carcinogens. (c) Errors of omission: micronutrient inadequacy is genotoxic. The major causes of cancer (other than smoking) do not involve exogenous carcinogenic chemicals: dietary imbalances, hormonal factors, infection and inflammation, and genetic factors. Insufficiency of many micronutrients, which appears to mimic radiation, is a preventable source of DNA damage. (d) Damage by distraction: regulating low hypothetical risks, Putting huge amounts of money into minuscule hypothetical risks damages public health by diverting resources and distracting the public from major risks. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Div Biochem & Mol Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Natl Inst Environm Hlth Sci Ctr, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ames, BN (reprint author), Univ Calif Berkeley, Div Biochem & Mol Biol, Berkeley, CA 94720 USA. RI huang, hongqi/N-1473-2014 NR 94 TC 69 Z9 71 U1 2 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0027-5107 J9 MUTAT RES-FUND MOL M JI Mutat. Res.-Fundam. Mol. Mech. Mutagen. PD JAN 17 PY 2000 VL 447 IS 1 BP 3 EP 13 DI 10.1016/S0027-5107(99)00194-3 PG 11 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 289WD UT WOS:000085644200002 PM 10686303 ER PT J AU Garrett, PE Baltzer, H Bertschy, M Burke, DG Deleze, M Drissi, S Gunther, C Jolie, J Kern, J Lehmann, H Mannanal, SJ Manns, J Muller, U Vorlet, JP Warr, N Weber, T AF Garrett, PE Baltzer, H Bertschy, M Burke, DG Deleze, M Drissi, S Gunther, C Jolie, J Kern, J Lehmann, H Mannanal, SJ Manns, J Muller, U Vorlet, JP Warr, N Weber, T TI Nuclear levels in Ir-190 studied with the Os-192(p,3n gamma) and Os-192(d,4ne(-)) reactions SO NUCLEAR PHYSICS A LA English DT Article DE Os-192(p,3n gamma), E=18.6, 20.8, 24.2, 27.2, 31.1; MeV; measured E gamma, I gamma(Ep), gamma gamma coin. t gamma - tRF-Os-192(d,4ne-), E=27.8 MeV; measured E-e-, I-e-, e(-)e(-) coin., life times; Ir-190 deduced levels, J, pi, t(1/2); two-quasiparticle-rotor calculations; enriched targets, Ge detectors, beta spectrometers ID FUSION REACTIONS; HIGH-SPIN; PARTICLE; PROTON; STATES; EXCITATIONS; INTENSITIES AB Nuclear levels in Ir-190 have been investigated with the Os-192(p,3n gamma) and Os-192(d,4n e(-)) reactions using beams of 18-31 MeV protons and 27.8 TvIeV deuterons, A series of measurements, including excitation, functions, gamma gamma and e(-) e(-)coincidences, and life time measurements, was performed. From the singles measurements, a total of 140 gamma rays were assigned as belonging to the Os-192(p,3n)Ir-190 channel. The results of the coincidence measurements show that many of these Lines are multiplets, Using information from a previous isomer study and single-nucleon transfer reactions, a level scheme is proposed comprising of 112 gamma rays placed between 76 levels. It is shown that most of the gamma intensity arises from bands having K-pi greater than or equal to 4(+). Several negative-par ity bands are also proposed. Calculations performed using values of is an element of and gamma characteristic of the region reproduce qualitatively some aspects of the level scheme. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Fribourg, Dept Phys, CH-1700 Fribourg, Switzerland. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Bonn, Inst Strahlen & Kernphys, D-53115 Bonn, Germany. RP Garrett, PE (reprint author), Inst Max Von Laue Paul Langevin, BP 156, F-38042 Grenoble 9, France. NR 28 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 17 PY 2000 VL 662 IS 3-4 BP 235 EP 266 DI 10.1016/S0375-9474(99)00365-6 PG 32 WC Physics, Nuclear SC Physics GA 280VP UT WOS:000085124700001 ER PT J AU Anisovich, AV Baker, CA Batty, CJ Bugg, DV Hasan, A Hodd, C Kisiel, J Nikonov, VA Sarantsev, AV Sarantsev, VV Zou, BS AF Anisovich, AV Baker, CA Batty, CJ Bugg, DV Hasan, A Hodd, C Kisiel, J Nikonov, VA Sarantsev, AV Sarantsev, VV Zou, BS TI Partial wave analysis of (p)over-barp -> pi(-)pi(+), pi(0)pi(0), eta eta and eta eta ' SO NUCLEAR PHYSICS A LA English DT Article DE mesons; resonances; annihilation ID AMPLITUDE ANALYSIS; RESONANCE REGION; CHANNEL; GEV/C; MESON; GLUEBALL AB A partial wave analysis is presented of Crystal Barrel data on (p) over bar p --> pi(0)pi(0), eta eta and eta eta' from 600 to 1940 MeV/c, combined with earlier data on d sigma/d Omega and P for (p) over bar p --> pi(-)pi(+). The following s-channel I = 0 resonances are identified: (i) J(PC) = 5(--) With mass and width (M, Gamma) at (2295 +/- 30, 235(-40)(+65)) MeV, (ii) J(PC) = 4(++) at (2020 +/- 12, 170 +/- 15) MeV and (2300 +/- 25, 270 +/- 50) MeV, (iii) D-3(3) J(PC) = 3(--) at (1960 +/- 15, 150 +/- 25) MeV and (2210 +/- 40, 360 +/- 55) MeV, and a (3)G(3) state at (2300(-80)(+50),340 +/- 150) MeV, (iv) J(PC) = 2(++) at (1910 +/- 30, 260 +/- 40) MeV, (2020 +/- 30, 275 +/- 35) MeV, (2230 +/- 30, 245 +/- 45) MeV, and (2300 +/- 35, 290 +/- 50) MeV, (v) J(PC) = 1(--) at (2005 +/- 40, 275 +/- 75) MeV, and (2165 +/- 40, 160(-70)(+140)) MeV, and (vi) J(PC) = 0(++) at (2005 +/- 30, 305 +/- 50) MeV, (2105 +/- 15, 200 +/- 25) MeV, and (2320 +/- 30, 175 +/- 45) MeV. In addition, there is a less well defined 6(++) resonance at 2485 +/- 40 MeV, with Gamma=410 +/- 90 MeV. For every J(P) almost all these resonances lie on well defined linear trajectories of mass squared versus excitation number. The slope is 1.10 +/- 0.03 GeV2 per excitation. The f(o)(2105) has strong coupling to eta eta, but much weaker coupling to pi(0)pi(0). Its flavour mixing angle between q (q) over bar and s (s) over bar is (59-71.6)degrees i.e. dominant decays to s (s) over bar. Such decays and its strong production in (p) over bar p interactions strongly suggest exotic character. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ London Queen Mary & Westfield Coll, London E1 4NS, England. PNPI, St Petersburg 188350, Russia. Silesian Univ, Katowice, Poland. RP Anisovich, AV (reprint author), SLAC, Stanford, CA 94305 USA. NR 42 TC 30 Z9 30 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD JAN 17 PY 2000 VL 662 IS 3-4 BP 319 EP 343 DI 10.1016/S0375-9474(99)00407-8 PG 25 WC Physics, Nuclear SC Physics GA 280VP UT WOS:000085124700005 ER PT J AU Dreesen, DS Albright, JN AF Dreesen, DS Albright, JN TI Models support potential for drilling deep microholes SO OIL & GAS JOURNAL LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dreesen, DS (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 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 JAN 17 PY 2000 VL 98 IS 3 BP 56 EP + PG 6 WC Energy & Fuels; Engineering, Petroleum SC Energy & Fuels; Engineering GA 277EY UT WOS:000084920800023 ER PT J AU Alavi-Harati, A Albuquerque, IF Alexopouos, T Arenton, M Arisaka, K Averitte, S Barker, AR Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hanagaki, K Hazumi, M Hidaka, S Hsiung, YB Jejer, V Jennings, J Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL McManus, AP Mikelsons, P Monnier, E Nakaya, T Nauenberg, U Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Qiao, C Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Shields, J Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Swanson, RA Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Wu, JY Yamanaka, T Zimmerman, ED AF Alavi-Harati, A Albuquerque, IF Alexopouos, T Arenton, M Arisaka, K Averitte, S Barker, AR Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hanagaki, K Hazumi, M Hidaka, S Hsiung, YB Jejer, V Jennings, J Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL McManus, AP Mikelsons, P Monnier, E Nakaya, T Nauenberg, U Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Qiao, C Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Shields, J Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Swanson, RA Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Wu, JY Yamanaka, T Zimmerman, ED CA KTeV Collaboration TI Observation of CP violation in K-L ->pi(+)pi(-)e(+)e(-) decays SO PHYSICAL REVIEW LETTERS LA English DT Article AB We report the first observation of a manifestly CP violating effect in the K-L --> pi(+) pi(-) e(+) e(-) decay mode. A large asymmetry was observed in the distribution of these decays in the CP-odd and T-odd angle phi between the decay planes of the e(+) e(-) and pi(+) pi(-) pairs in the K-L center of mass system. After acceptance corrections, the overall asymmetry is found to be [13.6 +/- 2.5(stat) +/- 1.2(syst)]%. This is the largest CP-violating effect yet observed when integrating over the entire phase space of a mode and the first such effect observed in an angular variable. C1 Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Colorado, Boulder, CO 80309 USA. Elmhurst Coll, Elmhurst, IL 60126 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Osaka Univ, Toyonaka, Osaka 560, Japan. Rice Univ, Houston, TX 77005 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. Univ Virginia, Inst Nucl & Particle Phys, Charlottesville, VA 22901 USA. Univ Wisconsin, Madison, WI 53706 USA. RP Cox, B (reprint author), Univ Arizona, Tucson, AZ 85721 USA. RI Albuquerque, Ivone/H-4645-2012 OI Albuquerque, Ivone/0000-0001-7328-0136 NR 10 TC 79 Z9 79 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 JAN 17 PY 2000 VL 84 IS 3 BP 408 EP 411 DI 10.1103/PhysRevLett.84.408 PG 4 WC Physics, Multidisciplinary SC Physics GA 274WD UT WOS:000084787300003 ER PT J AU Watanabe, H Mukai, T Nieh, TG Higashi, K AF Watanabe, H Mukai, T Nieh, TG Higashi, K TI Low temperature superplasticity in a magnesium-based composite SO SCRIPTA MATERIALIA LA English DT Article DE magnesium-based composite; low temperature superplasticity; elongation-to-failure; stress exponent; activation energy ID STRAIN-RATE SUPERPLASTICITY; AL-LI ALLOYS; DISCONTINUOUS FIBER; MATRIX COMPOSITES; VORTEX METHOD; MG ALLOY; DEFORMATION; ZK60/SIC/17P; EQUATION; STRESS C1 Osaka Municipal Tech Res Inst, Joto Ku, Osaka 5368553, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Osaka Prefecture, Coll Engn, Sakai, Osaka 5998531, Japan. RP Watanabe, H (reprint author), Osaka Municipal Tech Res Inst, Joto Ku, 1-6-50 Morinomiya, Osaka 5368553, Japan. RI Nieh, Tai-Gang/G-5912-2011; Mukai, Toshiji/F-9570-2014; Totsukawa, Nobuhisa/D-2028-2017; OI Nieh, Tai-Gang/0000-0002-2814-3746; Mukai, Toshiji/0000-0002-9628-5762; Watanabe, Hiroyuki/0000-0002-4236-2945 NR 35 TC 32 Z9 40 U1 1 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JAN 17 PY 2000 VL 42 IS 3 BP 249 EP 255 DI 10.1016/S1359-6462(99)00357-7 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 280VW UT WOS:000085125300005 ER PT J AU Pike, LM Liu, CT AF Pike, LM Liu, CT TI Environmental effects on the tensile properties of two Ni3Si-based alloys SO SCRIPTA MATERIALIA LA English DT Article DE Ni3Si-based alloy; intermetallic; embrittlement ID BORON-DOPED NI3AL; GRAIN-BOUNDARY FRACTURE; NI3SI; EMBRITTLEMENT; DUCTILITY; INTERMETALLICS; 600-DEGREES-C C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Pike, LM (reprint author), Haynes Int Inc, Kokomo, IN 46904 USA. OI Liu, Chain Tsuan/0000-0001-7888-9725 NR 16 TC 23 Z9 25 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JAN 17 PY 2000 VL 42 IS 3 BP 265 EP 270 DI 10.1016/S1359-6462(99)00360-7 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 280VW UT WOS:000085125300007 ER PT J AU Shalliker, RA Broyles, BS Guiochon, G AF Shalliker, RA Broyles, BS Guiochon, G TI On-column visualization of sample migration in liquid chromatography SO ANALYTICAL CHEMISTRY LA English DT Article ID PREPARATIVE COLUMNS; PACKING METHODS; HETEROGENEITY; EFFICIENCY; BEDS AB A quantitative on-column visualization technique for evaluating solute migration in liquid chromatography columns was described. This technique employed a matched refraction index phase system in high-pressure glass columns. In this case, the mobile phase was carbon tetrachloride and the stationary phase was a C18 silica, Because the refractive indexes of the two phases were the same, the column bed, otherwise opaque, was transparent to the eye. Zones of colored solutes could be injected (iodine for instance) and their migration studied along the column. Photographing the sample band during its migration allowed chromatographic information to be extracted using digital technology. As an example of applications for this technique, we show the sample entry through various inlet fittings, The results demonstrate that chromatographers should pay more attention to the selection of inlet frits. Importantly, the frit porosity should be matched to the particle size of the packing. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 17 TC 38 Z9 39 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JAN 15 PY 2000 VL 72 IS 2 BP 323 EP 332 DI 10.1021/ac990370+ PG 10 WC Chemistry, Analytical SC Chemistry GA 276BG UT WOS:000084855300009 PM 10658326 ER PT J AU Barrett, CL Mortveit, HS Reidys, CM AF Barrett, CL Mortveit, HS Reidys, CM TI Elements of a theory of simulation - II: sequential dynamical systems SO APPLIED MATHEMATICS AND COMPUTATION LA English DT Article DE sequential dynamical systems; fixed points; structure; orderings ID ACYCLIC ORIENTATIONS; BOUNDS; NUMBER AB We study a class of discrete dynamical systems that is motivated by the generic structure of simulations. The systems consist of the following data: (a) a finite graph Y with vertex set (1,..., n) where each vertex has a binary state, (b) functions F-i : F-2(n) --> F-2(n) and (c) an update ordering pi. The functions F-i update the binary state of vertex i as a function of the state of vertex i and its Y-neighbors and leave the states of all other vertices fixed. The update ordering is a permutation of the Y-vertices. By composing the functions F-i in the order given by pi one obtains the sequential dynamical system (SDs): [GRAPHICS] We derive a decomposition result, characterize invertible SDs and study fixed points. In particular we analyse how many different SDs that can be obtained by reordering a given multiset of update functions and give a criterion for when one can derive concentration results on this number, Finally, some specific SDs are investigated. (C) 2000 Elsevier Science Inc. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, TSA DO SA, Los Alamos, NM 87545 USA. RP Barrett, CL (reprint author), Univ Calif Los Alamos Natl Lab, TSA DO SA, Mailstop TA-0,SM-1237,MS M997, Los Alamos, NM 87545 USA. NR 15 TC 33 Z9 33 U1 1 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0096-3003 J9 APPL MATH COMPUT JI Appl. Math. Comput. PD JAN 15 PY 2000 VL 107 IS 2-3 BP 121 EP 136 DI 10.1016/S0096-3003(98)10114-5 PG 16 WC Mathematics, Applied SC Mathematics GA 260CV UT WOS:000083932700006 ER PT J AU Jung, CH Hartman, FC Lu, TYS Larimer, FW AF Jung, CH Hartman, FC Lu, TYS Larimer, FW TI D-ribose-5-phosphate isomerase from spinach: Heterologous overexpression, purification, characterization, and site-directed mutagenesis of the recombinant enzyme SO ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS LA English DT Article DE ribose-5-phosphate isomerase; active site; mutagenesis ID TRIOSE PHOSPHATE ISOMERASE; COMPLETE GENOME SEQUENCE; ESCHERICHIA-COLI; RIBOSE-5-PHOSPHATE ISOMERASE; PHOSPHOGLUCOSE ISOMERASE; ACTIVE-SITE; MECHANISM; GENE; EVOLUTION AB A cDNA encoding spinach chloroplastic ribose-5-phosphate isomerase (RPI) was cloned and overexpressed in Escherichia coli, and a purification scheme for the recombinant enzyme was developed. The purified recombinant RPI is a homodimer of 25-kDa subunits and shows kinetic properties similar to those of the homodimeric enzyme isolated from spinach leaves (A. C. Rutner, 1970, Biochemistry 9, 178-184). Phosphate, used as a buffer in previous studies, is a competitive inhibitor of RPI with a K-i of 7.9 mM, D-Arabinose 5-phosphate is an effective inhibitor, while D-xylulose-5 phosphate is not, indicating that the configuration at carbon-3 contributes to substrate recognition, Although D-arabinose 5-phosphate binds to RPI, it is not isomerized, demonstrating that the configuration at carbon-3 is crucial for catalysis. Alignment of RPI sequences from diverse sources showed that only 11 charged amino acid residues of the 236-residue subunit are conserved. The possible function of four of these residues was examined by site-directed mutagenesis. D87A, K100A, and D90A mutants show greatly diminished k(cat) values (0.0012, 0.074, and 0.38% of the wild type, respectively), while E91A retains substantial activity. Only insignificant or moderate changes in K-m of D-ribose 5-phosphate are observed for D87A, K100A, and D90A, indicating a direct or indirect catalytic role of the targeted residues. (C) 2000 Academic Press. C1 Oak Ridge Natl Lab, Div Life Sci, Prot Engn Program, Oak Ridge, TN 37831 USA. Univ Tennessee, Oak Ridge Grad Sch Biomed Sci, Oak Ridge, TN 37831 USA. RP Larimer, FW (reprint author), Oak Ridge Natl Lab, Div Life Sci, Prot Engn Program, 1060 Commerce Pk, Oak Ridge, TN 37831 USA. NR 62 TC 21 Z9 21 U1 2 U2 5 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-9861 J9 ARCH BIOCHEM BIOPHYS JI Arch. Biochem. Biophys. PD JAN 15 PY 2000 VL 373 IS 2 BP 409 EP 417 DI 10.1006/abbi.1999.1554 PG 9 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 279FD UT WOS:000085033000013 PM 10620366 ER PT J AU Delhommeau, F Cynober, T Schischmanoff, PO Rohrlich, P Delaunay, J Mohandas, N Tchernia, G AF Delhommeau, F Cynober, T Schischmanoff, PO Rohrlich, P Delaunay, J Mohandas, N Tchernia, G TI Natural history of hereditary spherocytosis during the first year of life SO BLOOD LA English DT Article ID LIGHT-SCATTERING; DIAGNOSIS; VOLUME AB Although hereditary spherocytosis (HS) is a common disorder of the red cell membrane, its clinical and biologic expression at birth and in early infancy has received little attention. In order to obtain insights into the natural history of HS during infancy, we studied 46 neonates, 39 from families in which 1 of the parents had previously been given a diagnosis of HS and 7 presenting with nonimmune hemolytic anemia and no family history of HS. Of these 46 neonates, 23 were subsequently confirmed to have HS and 23 were found to be healthy. The hematologic and biologic analyses carried out in this cohort of 46 newborns enabled us to develop guidelines for early diagnosis of HS. A careful clinical follow-up of 34 HS patients during the-first year of life allowed us to define several important clinical features of HS during this period. Hemoglobin values are usually normal at birth but decrease sharply during the subsequent 20 days, which leads, in many cases, to a transient and severe anemia. The anemia is severe enough to warrant blood transfusions in a large number of infants with HS (26 of 34 in our series). The aggravation of anemia appears to be related to the inability of these infants to mount an appropriate erythropoietic response to anemia and to the development of splenic filtering function. These findings indicate that careful monitoring of infants with HS during the first 6 months of life is important for appropriate clinical management. (Blood, 2000;95:393-397) (C) 2000 by The American Society of Hematology. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Assistance Publ Hop Paris, Hop Bicetre, Hematol Lab, Le Kremlin Bicetre, France. Assistance Publ Hop Paris, Hop Bicetre, Biochim Lab, Le Kremlin Bicetre, France. Fac Med Paris 11, Le Kremlin Bicetre, France. Assistance Publ Hop Paris, Hop Robert Debre, Serv Pediat Hematol, Paris, France. RP Mohandas, N (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Mailstop 74-157,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Brugnara, Carlo/A-8041-2010 OI Brugnara, Carlo/0000-0001-8192-8713 FU NIDDK NIH HHS [DK26263] NR 22 TC 37 Z9 40 U1 0 U2 4 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1200 19TH ST, NW, STE 300, WASHINGTON, DC 20036-2422 USA SN 0006-4971 J9 BLOOD JI Blood PD JAN 15 PY 2000 VL 95 IS 2 BP 393 EP 397 PG 5 WC Hematology SC Hematology GA 272QG UT WOS:000084662000005 PM 10627440 ER PT J AU Gee, SL Aoyagi, K Lersch, R Hou, V Wu, M Conboy, JG AF Gee, SL Aoyagi, K Lersch, R Hou, V Wu, M Conboy, JG TI Alternative splicing of protein 4.1R exon 16: ordered excision of flanking introns ensures proper splice site choice SO BLOOD LA English DT Article ID PRE-MESSENGER-RNA; SPECTRIN-ACTIN-BINDING; HEREDITARY ELLIPTOCYTOSIS; MEMBRANE STABILITY; TERNARY COMPLEX; SR PROTEINS; DOMAIN; ELEMENT; MECHANOCHEMISTRY; DIFFERENTIATION AB Alternative splicing plays a major role in regulating tissue-specific expression of cytoskeletal protein 4.1R isoforms. In particular, expression of the protein's functionally critical spectrin actin binding domain, essential for maintenance of red cell membrane mechanical properties, is governed by a developmentally regulated splicing switch involving alternative exon 16. Using a model 3-exon 4.1R pre-messenger RNA (pre-mRNA), we explored the sequence requirements for excision of the introns flanking exon 16. These studies revealed that splicing of this alternative exon occurs preferentially in an ordered fashion. The first step is excision of the downstream intron to join exons 16 and 17, followed by excision of the upstream intron, Constructs designed to test the converse pathway were spliced less efficiently and with less fidelity, in part due to activation of a cryptic 5' splice site in exon 16. This downstream-first model for ordered splicing is consistent with the hypothesis that regulated alternative splicing requires cooperation between multiple exonic and/or intronic regulatory elements whose spatial organization is critical for recruitment of appropriate splicing factors. Our results predict that exon 16 splicing is regulated at the first step-excision of the downstream intron-and that cells unable to catalyze this step will exhibit exon 16 skipping, In cells that include exon 16, adherence to an ordered pathway is important for efficient and accurate production of mature 4.1R mRNA encoding an intact spectrin-actin binding domain. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Perkin Elmer Appl Biosyst, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Cellular & Mol Biol, Berkeley, CA 94720 USA. RP Conboy, JG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Mailstop 74-157,1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [HL45182, R01 HL045182] NR 40 TC 17 Z9 17 U1 0 U2 0 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1200 19TH ST, NW, STE 300, WASHINGTON, DC 20036-2422 USA SN 0006-4971 J9 BLOOD JI Blood PD JAN 15 PY 2000 VL 95 IS 2 BP 692 EP 699 PG 8 WC Hematology SC Hematology GA 272QG UT WOS:000084662000047 PM 10627481 ER PT J AU Bito, T Roy, S Sen, CK Packer, L AF Bito, T Roy, S Sen, CK Packer, L TI Pine bark extract pycnogenol downregulates IFN-gamma-induced adhesion of T cells to human keratinocytes by inhibiting inducible ICAM-1 expression SO FREE RADICAL BIOLOGY AND MEDICINE LA English DT Article DE flavonoids; procyanidins; plant polyphenols; reactive oxygen species; skin inflammation; Stat1; free radicals ID INTERFERON-GAMMA; EPIDERMAL-KERATINOCYTES; MOLECULE-1 ICAM-1; GENE-EXPRESSION; INDUCTION; ANTIOXIDANT; ACTIVATION; FLAVONOIDS; DERMATOLOGY; QUERCETIN AB Expression of intercellular adhesion molecule-1 (ICAM-1) is necessary for leukocyte/keratinocyte interactions. Upregulation of ICAM-1 expression in keratinocytes has been observed in several inflammatory dermatoses, such as psoriasis, atopic dermatitis, and lupus erythematosus. Inflammatory cytokines, such as interferon-gamma (IFN-gamma), upregulate ICAM-1 expression in keratinocytes. Because of potent antioxidant and anti-inflammatory properties of the French maritime pine bark extract, Pycnogenol (Horphag Research, Geneva, Switzerland), its effects were investigated on the interaction of T cells with keratinocytes after activation with IFN-gamma and the molecular mechanisms involved in such interactions. Studies were performed using a human keratinocyte cell line, HaCaT. Cell adhesion in the presence of IFN-gamma was studied using a coculture assay. Treatment of HaCaT cells with 20 U/ml IFN-gamma for 24 h markedly induced adherence of Jurkat T cells to HaCaT cells. PYC pretreatment (50 mu g/ml, 12 h) significantly inhibited IFN-gamma induced adherence of T cells to HaCaT cells (p < .01). ICAM-1 plays a major role in the IFN-gamma-induced adherence of T cells to keratinocytes. Thus, the effect of PYC on IFN-gamma-induced ICAM-1 expression was investigated as well. Pretreatment of HaCaT cells with PYC significantly inhibited IFN-gamma-induced expression of ICAM-1 expression in HaCaT cells. The downregulation of inducible ICAM-1 expression by PYC was both dose and time dependent. A 50 mu g/ml dose of PYC and a 12 h pretreatment time (i.e., before activation with IFN-gamma) provided maximal (similar to 70%) inhibition of inducible ICAM-1 expression in HaCaT cells. Gamma-activated sequence present on the ICAM-1 gene confers IFN-gamma responsiveness in selected cells of epithelial origin (e.g., keratinocytes) that are known to express ICAM-1 on activation with IFN-gamma. Gel-shift assays revealed that PYC inhibits IFN-gamma-mediated activation of Stat1, thus suggesting a transcriptional regulation of inducible ICAM-1 expression by PYC. These results indicate the therapeutic potential of PYC in patients with inflammatory skin disorders. (C) 2000 Elsevier Science Inc. C1 Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Roy, S (reprint author), Univ Calif Berkeley, Dept Mol & Cell Biol, 251 Life Sci Addit, Berkeley, CA 94720 USA. RI Sen, Chandan/A-8762-2013; Roy, sashwati/E-3990-2011 NR 40 TC 45 Z9 52 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0891-5849 J9 FREE RADICAL BIO MED JI Free Radic. Biol. Med. PD JAN 15 PY 2000 VL 28 IS 2 BP 219 EP 227 DI 10.1016/S0891-5849(99)00229-4 PG 9 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA 283MV UT WOS:000085280100007 PM 11281289 ER PT J AU Pohl, U Smith, JS Tachibana, I Ueki, K Lee, HK Ramaswamy, S Wu, Q Mohrenweiser, HW Jenkins, RB Louis, DN AF Pohl, U Smith, JS Tachibana, I Ueki, K Lee, HK Ramaswamy, S Wu, Q Mohrenweiser, HW Jenkins, RB Louis, DN TI EHD2, EHD3, and EHD4 encode novel members of a highly conserved family of EH domain-containing proteins SO GENOMICS LA English DT Article ID TUMOR-SUPPRESSOR GENE; MEDIATED ENDOCYTOSIS; EXON AMPLIFICATION; CHROMOSOME 19Q13.3; EPS15; OLIGODENDROGLIOMAS; ASTROCYTOMAS; SPECIFICITY; DELETION; REGION AB Exon trapping from a bacterial artificial chromosome (BAC 78138) mapping to the 19q13.3 glioma tumor suppressor candidate region yielded two exons that recognized a 3.6-kb transcript on Northern blot, Screening of a human fetal brain cDNA library with these exons identified three novel genes, designated EHD2, EHD3, and EHD4, which are homologous to the recently characterized human EHD1 (testilin/HPAST) and its mouse homolog Ehd1, as well as to homologs in Drosophila (Past1) and Caenorhabditis elegans. Alignment of the predicted peptide sequences revealed striking similarities, with multiple conserved regions that include a nucleotide-binding consensus site at the N-terminus, a bipartite nuclear localization signal, and an eps15 homology (EH) protein-binding domain with an EF-hand motif at the C-terminus. The genes are specifically expressed, with EHD2 highly expressed in heart, EHD3 in brain and heart, and EHD4 in heart and pancreas. EHD2 was confirmed to originate from BAC 78138 at 19q13.3; radiation hybrid mapping localized EHD3 and EHD4 to 2p21 and 15q11.1, respectively; EHD1 has been previously mapped to 11q13. The three EHD1 paralogs therefore represent novel members of a family of human EH domain-containing proteins that may play a role in endocytosis and signaling. Mutation analysis of the five coding exons of EHD2 in gliomas failed to detect any tumor-specific alterations, thus indicating that EHD2 is an unlikely candidate for the 19q tumor suppressor gene. (C) 2000 Academic Press. C1 Massachusetts Gen Hosp, Dept Pathol, Mol Neurooncol Lab, Boston, MA 02129 USA. Massachusetts Gen Hosp, Neurosurg Serv, Mol Neurooncol Lab, Boston, MA 02129 USA. Harvard Univ, Sch Med, Boston, MA 02129 USA. Mayo Clin & Mayo Fdn, Div Lab Genet, Rochester, MN 55905 USA. Harvard Univ, Dept Cellular & Mol Biol, Cambridge, MA 02138 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Louis, DN (reprint author), Massachusetts Gen Hosp, Mol Neurooncol Lab, Dept Pathol, CNY6,149 13th St, Charlestown, MA 02129 USA. RI imoto, Issei/D-8065-2012; Wu, Qiang/A-6751-2009 OI Wu, Qiang/0000-0003-3841-3591 FU NCI NIH HHS [CA 69285, CA 50905] NR 30 TC 68 Z9 72 U1 0 U2 5 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD JAN 15 PY 2000 VL 63 IS 2 BP 255 EP 262 DI 10.1006/geno.1999.6087 PG 8 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 286PB UT WOS:000085453400009 PM 10673336 ER PT J AU Eack, KB Suszcynsky, DM Beasley, WH Roussel-Dupre, R Symbalisty, E AF Eack, KB Suszcynsky, DM Beasley, WH Roussel-Dupre, R Symbalisty, E TI Gamma-ray emissions observed in a thunderstorm anvil SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HIGH-ALTITUDE DISCHARGES; X-RAYS; AIR BREAKDOWN AB Balloon-borne gamma-ray and electric-field-change instruments were launched into a daytime summer thunderstorm to evaluate a new experimental design to test hypotheses for the production of transient luminous events (TLE) (eg. sprites, and blue jets) in the mesosphere. While ascending, the instrument triggered many times on the signals from the electric-field-change instrument, recording the gamma-ray background at those times. A greater than three-fold increase in the gamma-ray flux was observed as the balloon descended through a thunderstorm anvil where a strong electric field was suspected to be present. These observations suggest that gamma-ray production in thunderstorms may not be as uncommon as previously believed. C1 Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. Univ Oklahoma, Sch Meteorol, Norman, OK 73019 USA. RP Eack, KB (reprint author), Los Alamos Natl Lab, Space & Atmospher Sci Grp, MS-D466, Los Alamos, NM 87545 USA. NR 19 TC 42 Z9 45 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2000 VL 27 IS 2 BP 185 EP 188 DI 10.1029/1999GL010849 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 275FA UT WOS:000084807700012 ER PT J AU Beasley, WH Eack, KB Morris, HE Rust, WD MacGorman, DR AF Beasley, WH Eack, KB Morris, HE Rust, WD MacGorman, DR TI Electric-field changes of lightning observed in thunderstorms SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HIGH-ALTITUDE DISCHARGES; BREAKDOWN AB During the Summer and Fall of 1998 we launched five balloon-borne instruments into thunderstorms to observe changes in the vertical component of electric field caused by lightning. Four of these were for measurement of field change only. The fifth was part of a larger package that included a gamma radiation detector and a GPS receiver on board. We have processed electric-field-change data from two of these flights. We discuss examples of field changes observed at altitude and compare them with data from the National Lightning Detection Network (NLDN) for cloud-to-ground lightning flashes that were coincident in time. Limits on time resolution and timing accuracy prevent unambiguous identification of the lightning processes that caused the field changes. It appears that they may have been caused by charge movements relatively near the instruments as compared with the ground-strike location of coincident flashes. C1 Univ Oklahoma, Sch Meteorol, Norman, OK 73019 USA. Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM USA. Univ Oklahoma, Dept Phys & Astron, Norman, OK 73019 USA. Natl Severe Storms Lab, Norman, OK 73069 USA. RP Beasley, WH (reprint author), Univ Oklahoma, Sch Meteorol, Norman, OK 73019 USA. NR 12 TC 3 Z9 3 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2000 VL 27 IS 2 BP 189 EP 192 DI 10.1029/1999GL010850 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 275FA UT WOS:000084807700013 ER PT J AU Caldeira, K Rau, GH AF Caldeira, K Rau, GH TI Accelerating carbonate dissolution to sequester carbon dioxide in the ocean: Geochemical implications SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CO2; DISPOSAL AB Various methods have been proposed for mitigating release of anthropogenic CO2 to the atmosphere, including deep-sea injection of CO2 captured from fossil-fuel fired power plants. Here, we use a schematic model of ocean chemistry and transport to analyze the geochemical consequences of a new method for separating carbon dioxide from a waste gas stream and sequestering it in the ocean. This method involves reacting CO2-rich power-plant gases with seawater to produce a carbonic acid solution which in turn is reacted on site with carbonate mineral (e.g., limestone) to form Ca2+ and bicarbonate in solution, which can then be released and diluted in the ocean. Such a process is similar to carbonate weathering and dissolution which would have otherwise occurred naturally, but over many millennia. Relative to atmospheric release or direct ocean CO2 injection, this method would greatly expand the capacity of the ocean to store anthropogenic carbon while minimizing environmental Impacts or mts carbon on ocean biota. This carbonate-dissolution technique may be more cost-effective and less environmentally harmful, and than previously proposed CO2 capture and sequestration techniques. C1 Univ Calif Lawrence Livermore Natl Lab, DOE Ctr Res Ocean Carbon Sequestrat, Livermore, CA 94550 USA. Univ Calif Santa Cruz, Inst Marine Sci, Santa Cruz, CA 95064 USA. RP Caldeira, K (reprint author), Univ Calif Lawrence Livermore Natl Lab, DOE Ctr Res Ocean Carbon Sequestrat, 7000 E Ave,L-103, Livermore, CA 94550 USA. RI Caldeira, Ken/E-7914-2011 NR 23 TC 57 Z9 58 U1 1 U2 17 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2000 VL 27 IS 2 BP 225 EP 228 DI 10.1029/1999GL002364 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 275FA UT WOS:000084807700022 ER PT J AU Bell, J Duffy, P Covey, C Sloan, L AF Bell, J Duffy, P Covey, C Sloan, L CA CMIP Investigators TI Comparison of temperature variability in observations and sixteen climate model simulations SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SOIL AB Understanding how much, if any, of observed climate changes are anthropogenic depends upon understanding the magnitude and spatial patterns of natural climate variability. We have compared simulated surface air temperature (SAT) variability in 16 coupled ocean-atmosphere-sea ice climate model simulations to observed temperature variability. The majority of the simulations exhibit excessive air temperature variability over land while simulated temperature variability over oceans is generally too low. The ratio of variability over land to over oceans is too high in all the simulations, relative to observations. We have identified several factors which may contribute to the differences in temperature variability. In particular, many of the models use "bucket" land surface schemes which produce greater temperature variability over land, due to lower levels of soil moisture, than more realistic land surface schemes produce. C1 Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. Univ Calif Lawrence Livermore Natl Lab, Div Atmospher Sci, Livermore, CA 94550 USA. RP Bell, J (reprint author), Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. NR 13 TC 25 Z9 25 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 15 PY 2000 VL 27 IS 2 BP 261 EP 264 DI 10.1029/1999GL006080 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 275FA UT WOS:000084807700031 ER PT J AU Skurski, P Gutowski, M Simons, J AF Skurski, P Gutowski, M Simons, J TI On the possibility of binding of two electrons to dipole potentials SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article ID MULTIPLY-CHARGED ANIONS; BOUND ANIONS; BASIS-SETS; STABILITIES; STATES; ATOMS AB The possibility of binding two electrons by the fixed finite dipole (FFD) potential due to two point charges + qe and - qe separated by the distance R is explored at the full configuration interaction level with extended basis sets. The critical value of the dipole moment mu = qR required to bind two electrons tends to infinity for small q (q approximate to 0.91e) and decreases precipitously as q increases. In the limit of very large q land small R), this critical dipole moment seems to approach a limit below 2 Debyes (D). It is shown analytically that in the point dipole limit this critical dipole value will approach that for binding a single electron. An extension of the FFD model to include effects of inner-shell core electrons allows the Li-, Na-, and K- cases (with a -1e charge at R) also to be examined. FFD-plus-core systems display even larger critical dipoles (113, 129, and 141 D, respectively) than does the + qe / - qe FFD potential (92.2 D). These findings suggest that it will be difficult to find a real molecule that can bind (by approximate to 1 cm(-1)) two electrons via its dipole potential. Finally, a simple electrostatic model is introduced which permits the critical dipole value of the FDD and its core-orbital extension to be evaluated rather well. (C) 2000 John Wiley & Sons, Inc. C1 Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA. Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Simons, J (reprint author), Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA. NR 31 TC 12 Z9 12 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD JAN 15 PY 2000 VL 76 IS 2 BP 197 EP 204 DI 10.1002/(SICI)1097-461X(2000)76:2<197::AID-QUA9>3.3.CO;2-4 PG 8 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA 265UC UT WOS:000084263300007 ER PT J AU Van Mourik, T Dunning, TH AF Van Mourik, T Dunning, TH TI Gaussian basis sets for use in correlated molecular calculations. VIII. Standard and augmented sextuple zeta correlation consistent basis sets for aluminum through argon SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article DE Gaussian basis sets; correlated calculations; Moller-Plesset perturbation theory; coupled cluster theory; multireference configuration interaction method; Al; Si; As; S; Cl; Ar ID CONFIGURATION-INTERACTION CALCULATIONS; ELECTRON CORRELATION-ENERGY; PLESSET PERTURBATION-THEORY; COUPLED-CLUSTER SINGLE; WAVE-FUNCTIONS; BENCHMARK CALCULATIONS; TRIPLE SUBSTITUTIONS; DISSOCIATION-ENERGY; DIATOMIC-MOLECULES; ATOMS AB Standard and augmented correlation consistent sextuple zeta (cc-pV6Z and aug-cc-pV6Z) basis sets have been determined for the second-row atoms aluminum through argon. Using these sets, dissociation energies and spectroscopic constants for the ground states of HCl, PN, and P-2 have been calculated using several theoretical methods, including Moller-Plesset perturbation theory, coupled cluster theory, and multireference configuration interaction theory (MRCI). The aug-cc-pV6Z and cc-pVbZ sets yield dissociation energies that are estimated to be within 0.1-0.2 kcal/mol of the complete basis set limit for HCl and within 1-1.5 kcal/mol for PN and P-2. The MRCI and CCSD(T) methods are found to give the most Consistently reliable results for the spectroscopic constants of all three species investigated. Use of the counterpoise correction improves the convergence behavior of the spectroscopic constants with increasing n for both the cc-pVnZ and aug-cc-pVnZ sets and should allow more accurate estimates of the complete basis set Limit to be predicted. (C) 2000 John Wiley & Sons, Inc. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Van Mourik, T (reprint author), UCL, Christopher Ingold Labs, 20 Gordon St, London WC1H 0AJ, England. RI van Mourik, Tanja/A-4007-2008 NR 79 TC 78 Z9 78 U1 1 U2 13 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0020-7608 EI 1097-461X J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD JAN 15 PY 2000 VL 76 IS 2 BP 205 EP 221 PG 17 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA 265UC UT WOS:000084263300008 ER PT J AU Cook, BA Harringa, JL Hansen, T AF Cook, BA Harringa, JL Hansen, T TI Electrical and thermal properties of Tb0.3Dy0.7Fe2-x SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Samples of Tb0.3Dy0.7Fe2-x where x=0.05-0.10 (TERFENOL-D) were characterized for electrical resistivity and thermal diffusivity between room temperature and the Curie temperature, which for this composition is 360 degrees C. Additionally, the thermal diffusivity of one of the samples was measured to 1000 degrees C. Measurements were performed on two different orientations of standard, production-grade, grain-oriented TERFENOL-D produced by a Bridgman growth technique at ETREMA Products, Inc. The orientations were parallel and normal to the < 112 > crystallographic direction. The electrical resistivity and thermal diffusivity both exhibited isotropic behavior over the temperature range studied. The electrical resistivity of all samples increased monotonically from 0.06 m Omega-cm at room temperature to 0.14 m Omega cm at 360 degrees C, consistent with behavior expected for normal metals. The thermal conductivity was found to decrease with temperature from 135 mW/cm degrees C at room temperature to 122 mW/cm degrees C at 360 degrees C. The thermal diffusivity was found to exhibit a sharp cusp in the vicinity of the Curie temperature, T-C, increasing with temperature for T > T-C. Application of the Wiedemann-Franz law indicates that over 86% of the heat is carried by electrons. (C) 2000 American Institute of Physics. [S0021-8979(00)02602-5]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. ATREMA Prod Inc, Ames, IA 50010 USA. RP Cook, BA (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 10 TC 5 Z9 8 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 15 PY 2000 VL 87 IS 2 BP 776 EP 780 DI 10.1063/1.371940 PG 5 WC Physics, Applied SC Physics GA 269YY UT WOS:000084506500025 ER PT J AU Hwang, SC Arlt, G AF Hwang, SC Arlt, G TI Switching in ferroelectric polycrystals SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CERAMICS; SIMULATION; MODEL AB The Rayleigh law and a propagating switching region of a ferroelectric polycrystal are studied with a finite element model. Each crystallite, represented by a cubic element in a finite element mesh, is a single domain that switches completely without a simulated domain wall motion. The model involves only electric field induced (i.e., ferroelectric) switching. Under a low applied field, the model reproduces the Rayleigh law. The model predicts that a switching crystallite and its follow-up switching crystallite are likely to be the nearest neighbors and that the switching sequence of the crystallites forms the shape of an ellipsoid the major axis of which is parallel with the applied field direction. A spontaneous polarization reverses by direct 180 degrees reorientation if only one layer of the finite elements between two electrodes is simulated but reverses by two consecutive 90 degrees domain reorientations if the number of stacked layers between the electrodes is equal to two or greater. (C) 1999 American Institute of Physics. [S0021-8979(99)04123-7]. C1 Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. Rhein Westfal TH Aachen, Inst Werkstoffe Elektrotech, D-52056 Aachen, Germany. RP Sandia Natl Labs, POB 5800,MSO847, Albuquerque, NM 87185 USA. EM schwang@sandia.gov NR 34 TC 36 Z9 36 U1 2 U2 13 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 JAN 15 PY 2000 VL 87 IS 2 BP 869 EP 875 DI 10.1063/1.371968 PG 7 WC Physics, Applied SC Physics GA 269YY UT WOS:000084506500040 ER PT J AU Curtiss, LA Raghavachari, K Redfern, PC Pople, JA AF Curtiss, LA Raghavachari, K Redfern, PC Pople, JA TI Gaussian-3 theory using scaled energies SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PARAMETRIZED CONFIGURATION-INTERACTION; DENSITY-FUNCTIONAL THEORIES; FIRST-ROW; BOND-ENERGIES; PCI-X; COMPUTATION; MOLECULES; TESTS; SET; CHN AB A modification of Guassian-3 (G3) theory using multiplicative scale factors, instead of the additive higher level correction, is presented. In this method, referred to as G3S, the correlation energy is scaled by five parameters and the Hartree-Fock energy by one parameter. The six parameters are fitted to the G2/97 test set of 299 energies and the resulting mean absolute deviation from experiment is 0.99 kcal/mol compared to 1.01 kcal/mol for G3 theory. The G3S method has the advantage compared to G3 theory in that it can be used for studying potential energy surfaces where the products and reactants have a different number of paired electrons. In addition, versions of the computationally less intensive G3(MP3) and G3(MP2) methods that use scaled energies are also presented. These methods, referred to as G3S(MP3) and G3S(MP2), have mean absolute deviations of 1.16 and 1.35 kcal/mol, respectively. (C) 2000 American Institute of Physics. [S0021-9606(00)30902-3]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. RP Curtiss, LA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 28 TC 100 Z9 101 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2000 VL 112 IS 3 BP 1125 EP 1132 DI 10.1063/1.480668 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900009 ER PT J AU Garza, J Nichols, JA Dixon, DA AF Garza, J Nichols, JA Dixon, DA TI The Hartree product and the description of local and global quantities in atomic systems: A study within Kohn-Sham theory SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DENSITY-FUNCTIONAL THEORY; SELF-INTERACTION CORRECTION; NMR SHIELDING CONSTANTS; AB-INITIO PREDICTION; SPIN-DENSITY; 2ND-ORDER HYPERPOLARIZABILITIES; VIBRATIONAL FREQUENCIES; POLYATOMIC-MOLECULES; DIPOLE-MOMENTS; EXCHANGE AB The Hartree product is analyzed in the context of Kohn-Sham theory. The differential equations that emerge from this theory are solved with the optimized effective potential using the Krieger, Li, and Iafrate approximation, in order to get a local potential as required by the ordinary Kohn-Sham procedure. Because the diagonal terms of the exact exchange energy are included in Hartree theory, it is self-interaction free and the exchange potential has the proper asymptotic behavior. We have examined the impact of this correct asymptotic behavior on local and global properties using this simple model to approximate the exchange energy. Local quantities, such as the exchange potential and the average local electrostatic potential are used to examine whether the shell structure in an atom is revealed by this theory. Global quantities, such as the highest occupied orbital energy (related to the ionization potential) and the exchange energy are also calculated. These quantities are contrasted with those obtained from calculations with the local density approximation, the generalized gradient approximation, and the self-interaction correction approach proposed by Perdew and Zunger. We conclude that the main characteristics in an atomic system are preserved with the Hartree theory. In particular, the behavior of the exchange potential obtained in this theory is similar to those obtained within other Kohn-Sham approximations. (C) 2000 American Institute of Physics. [S0021-9606(00)31401-5]. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Autonoma Metropolitana Iztapalapa, Dept Quim, Div Ciencias Bas & Ingn, Mexico City 09340, DF, Mexico. RP Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. EM david.dixon@pnl.gov RI Garza, Jorge/H-9395-2016; Garza-Olguin, Jorge/N-3106-2016; OI Garza, Jorge/0000-0003-4249-6078; Garza-Olguin, Jorge/0000-0003-4249-6078; Nichols, Jeffrey/0000-0001-5454-9726 NR 72 TC 22 Z9 22 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2000 VL 112 IS 3 BP 1150 EP 1157 DI 10.1063/1.480669 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900011 ER PT J AU Song, Y Evans, M Ng, CY Hsu, CW Jarvis, GK AF Song, Y Evans, M Ng, CY Hsu, CW Jarvis, GK TI Rotationally resolved pulsed-field ionization photoelectron bands for O-2(+)(A (2)Pi(u),v(+)=0-12) in the energy range of 17.0-18.2 eV SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HIGH-RESOLUTION THRESHOLD; SYNCHROTRON-RADIATION; SPECTROSCOPY; O-2; PHOTOIONIZATION; OXYGEN AB We have obtained rotationally resolved pulsed-field ionization photoelectron (PFI-PE) spectra for O-2 in the energy range of 17.05-18.13 eV, covering the ionization transitions O-2(+)(A (2)Pi(u),v(+)=0-12,N+)<-- O-2(X (3)Sigma(g)(-),v "=0,N "). Although these O-2(+)(A (2)Pi(u),v(+)) PFI-PE bands have significant overlaps with vibrational bands for O-2(+)(a (4)Pi(u)) and O-2(+)(X (2)Pi(g)), we have identified all the O-2(+)(A (2)Pi(u),v(+)=0-12) bands by simulation of spectra obtained using supersonically cooled O-2 samples with rotational temperatures approximate to 20 and 220 K. While these v(+)=0-12 PFI-PE bands represent the first rotationally resolved photoelectron data for O-2(+)(A (2)Pi(u)), the PFI-PE bands for O-2(+)(A (2)Pi(u),v(+)=9 and 10) are the first rotationally resolved spectroscopic data for these levels. The simulation also allows the determination of accurate ionization energies, vibrational constants, and rotational constants for O-2(+)(A (2)Pi(u),v(+)=0-12). The analysis of the PFI-PE spectra supports the conclusion of the previous emission study that the O-2(+)(A (2)Pi(u),v(+)=9 and 10) states are strongly perturbed by a nearby electronic state. (C) 2000 American Institute of Physics. [S0021-9606(00)01703-7]. C1 Iowa State Univ, US Dept Energy, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Ng, CY (reprint author), Iowa State Univ, US Dept Energy, Ames Lab, Ames, IA 50011 USA. NR 35 TC 9 Z9 10 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2000 VL 112 IS 3 BP 1271 EP 1278 DI 10.1063/1.480596 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900023 ER PT J AU Song, Y Evans, M Ng, CY Hsu, CW Jarvis, GK AF Song, Y Evans, M Ng, CY Hsu, CW Jarvis, GK TI Rotationally resolved pulsed field ionization photoelectron bands for O-2(+)(a (4)Pi(u), v(+)=0-18) in the energy range of 16.0-18.0 eV SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HIGH-RESOLUTION THRESHOLD; SYNCHROTRON-RADIATION; SPECTROSCOPY; PHOTOIONIZATION; O-2; INTENSITIES; MOLECULES; SPECTRUM; OXYGEN AB We have obtained rotationally resolved pulsed field ionization-photoelectron (PFI-PE) spectra of O-2 in the energy range of 16.0-18.0 eV, covering ionization transitions O-2(+)(a (4)Pi(u), v(+)=0-18,J(+))<-- O-2(X (3)Sigma(g)(.), v "=0,N "). Although these vibrational PFI-PE bands for O-2(+)(a (4)Pi(u), v(+)) have significant overlaps with those for O-2(+)(X (2)Pi(g)) and O-2(+)(A (2)Pi(u)), we have identified all O-2(+)(a (4)Pi(u), v(+)=0-18) bands by simulation of spectra obtained using supersonically cooled O-2 samples with rotational temperatures approximate to 20 and 220 K. While the v(+)=4-18PFI-PE bands represent the first rotationally resolved photoelectron data for O-2(+)(a (4)Pi(u)), the PFI-PE bands for O-2(+)(a (4)Pi(u), v(+)=10-18) are the first rotationally resolved spectroscopic data for these levels. The simulation also allows the determination of accurate ionization energies, vibrational constants, and rotational constants for O-2(+)(a (2)Pi(u), v(+)=0-18). The observed intensities of spin-orbit components for the majority of O-2(+)(a (2)Pi(u), v(+)) vibrational bands are in accordance with the forced spin-orbit/rotational autoionization mechanism. (C) 2000 American Institute of Physics. [S0021-9606(00)02003-1]. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Ng, CY (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. NR 38 TC 12 Z9 13 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2000 VL 112 IS 3 BP 1306 EP 1315 DI 10.1063/1.480682 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900027 ER PT J AU Liu, GK Zhorin, VV Antonio, MR Li, ST Williams, CW Soderholm, L AF Liu, GK Zhorin, VV Antonio, MR Li, ST Williams, CW Soderholm, L TI Studies of local structure of Cm3+ in borosilicate glass using laser and x-ray spectroscopic methods and computational modeling SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ABSORPTION FINE-STRUCTURE; BEARING SILICATE-GLASSES; SYSTEMATIC ANALYSIS; FLUORESCENCE; SPECTRA; LUPO4; ENVIRONMENTS; SCATTERING; ELEMENTS; SOLIDS AB The local environment of Cm3+ in a borosilicate glass has been probed by a combination of laser spectroscopy, structural modeling, and extended x-ray absorption fine structure (EXAFS) spectroscopy. The Stark splitting for the Cm f-f state transitions is significantly larger than the inhomogeneous line broadening that results from the disordered environment. As a result, the Cm optical spectrum can be fit using an effective operator Hamiltonian to obtain a set of crystal-field parameters. The fitting procedure, which requires the use of a descent-in-symmetry approach, provides a set of parameters for a best fit within tetragonal symmetry. These parameters are then linked to the local environment of Cm through exchange-charge modeling (ECM) of crystal field interactions. Cm in our borosilicate glass is best modeled with six oxygen ions with approximately tetragonal symmetry, and at an average distance of 2.31 (3) Angstrom. The results of crystal-field modeling are supported by EXAFS results. (C) 2000 American Institute of Physics. [S0021-9606(00)71002-6]. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Liu, GK (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Zhorin, Victor/0000-0001-9777-4421 NR 48 TC 13 Z9 13 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2000 VL 112 IS 3 BP 1489 EP 1496 DI 10.1063/1.480687 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900048 ER PT J AU Garde, S Khare, R Hummer, G AF Garde, S Khare, R Hummer, G TI Microscopic density fluctuations and solvation in polymeric fluids SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; HYDROPHOBIC INTERACTIONS; SOLUBILITY; POLYETHYLENE; LIQUIDS; EQUILIBRIUM; CAVITIES; SYSTEMS; FORCES; GASES AB The information theory approach is used to study molecular-scale density fluctuations and solvation of hard-core molecules in a condensed polymeric system, supported by extensive computer simulations. In contrast to simple liquids, it is found that the bond connectivity in polymers leads to non-Gaussian density fluctuations in molecular volumes. We define "renormalized" polymers with a reduced number of monomers of increased effective size. This reduces correlations between monomers and simplifies the effective density fluctuations. Chemical potentials of hard-core solutes in polyethylene can then be calculated accurately using information theory. (C) 2000 American Institute of Physics. [S0021-9606(00)51403-2]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Mol Simulat Inc, San Diego, CA 92121 USA. RP Garde, S (reprint author), Rensselaer Polytech Inst, Isermann Dept Chem Engn, Troy, NY 12180 USA. RI Garde, Shekhar/C-3060-2008; Khare, Rajesh/J-2079-2014; Hummer, Gerhard/A-2546-2013 OI Khare, Rajesh/0000-0002-8859-766X; Hummer, Gerhard/0000-0001-7768-746X NR 38 TC 8 Z9 8 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2000 VL 112 IS 3 BP 1574 EP 1578 DI 10.1063/1.480705 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900059 ER PT J AU Qi, SY Chakraborty, AK AF Qi, SY Chakraborty, AK TI Theoretical study of polymeric mixtures with different sequence statistics. I. Ising class: Linear random copolymers with different statistical sequences and ternary blends of linear random copolymers with homopolymers SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MULTICOMPONENT POLYOLEFIN BLENDS; BLOCK COPOLYMER; THERMODYNAMIC INTERACTIONS; RANDOM HETEROPOLYMERS; PHASE-EQUILIBRIA; CO-POLYMERS; INTERFACES; SYSTEMS; SCATTERING; SEPARATION AB We derive a Landau free energy functional for polymeric mixtures containing components with different sequence statistics. We then apply this general field theory to two mixtures that belong to the Ising universality class: mixtures of two different linear random copolymers, and ternary systems of linear random copolymers and two homopolymers. We discuss the instability conditions for the homogeneous state of these mixtures, and calculate the structure factors for different components in the homogeneous state. The structure factors show interesting features which can directly be compared with scattering experiments carried out with selectively deuterated samples. We also work out the eigenmodes representing the least stable concentration fluctuations for these mixtures. The nature of these concentration fluctuations provides information regarding the ordered phases and the kinetic pathways that lead to them. We find various demixing modes for different characteristics of the two mixtures (e.g., average compositions, statistical correlation lengths, and volume fractions). (C) 2000 American Institute of Physics. [S0021-9606(00)50303-1]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Qi, SY (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem Engn, Berkeley, CA 94720 USA. NR 33 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2000 VL 112 IS 3 BP 1585 EP 1597 DI 10.1063/1.480707 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900061 ER PT J AU Qi, SY Chakraborty, AK AF Qi, SY Chakraborty, AK TI Theoretical study of polymeric mixtures with different sequence statistics. II. Brazovskii class: Linear random copolymers with diblock copolymers SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID BLOCK-COPOLYMER; RANDOM HETEROPOLYMERS; MICROPHASE SEPARATION; PHASE-EQUILIBRIA; CO-POLYMERS; BLENDS; THERMODYNAMICS; HOMOPOLYMERS; RECOGNITION; INTERFACES AB We use a Landau theory to study the instability of the homogeneous state of a mixture of linear random copolymers and diblock copolymers. Interesting features of the calculated structure factors for different components of the mixture are found, which can be directly compared with scattering experiments with selectively deuterated samples. We also investigate the least stable concentration fluctuations and find four different types of segregation modes at the spinodal depending upon the characteristics of the mixture (e.g., average compositions, statistical correlation lengths and volume fractions). The different segregation modes are also indicative of the kinetic pathways leading to the formation of ordered microstructures. Experiments probing these pathways are suggested. (C) 2000 American Institute of Physics. [S0021-9606(00)50403-6]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Qi, SY (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem Engn, Berkeley, CA 94720 USA. NR 31 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 15 PY 2000 VL 112 IS 3 BP 1598 EP 1605 DI 10.1063/1.480599 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 271MW UT WOS:000084598900062 ER PT J AU Kwon, YK Pyda, M Chen, W Wunderlich, B AF Kwon, YK Pyda, M Chen, W Wunderlich, B TI Thermal properties of poly(ester-imide)s with C12H24 and C22H44 groups SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article; Proceedings Paper CT 26th NATAS Conference CY SEP 13-15, 1998 CL CLEVELAND, OHIO DE poly(ester imide); heat capacity; DSC; entropy; enthalpy; free enthalpy; crystallinity; vibrational spectrum; large-amplitude motion; PEIM ID LINEAR MACROMOLECULES; HEAT-CAPACITIES; PHENYLENE GROUPS; ADDITION SCHEME; POLYMERS; LIQUID; CRYSTALLIZATION; COMPUTATION; VIBRATIONS; TRANSITION AB The thermal properties of poly(4,4'-phthaloimidobenzoyl-n-methyleneoxy-carbonyl) with n = 12 and 22, abbreviated as PEIM-18 and PEIM-22, respectively, have been studied using differential scanning calorimetry (DSC). The heat capacities of the solid states of both polymers were measured and compared to computed heat capacities from approximate vibrational spectra. The deviations from the vibrations-only heat capacity were used to identify large-amplitude, conformational motions. The heat capacities of the liquid states were described as linear functions of temperature. They agreed with the liquid heat capacities generated from the ATHAS addition scheme using group contributions derived from polymers containing the same chemical segments as the PEIM-ns. Knowing the heat capacities for the solid and liquid, the transition parameters could be separated and enthalpies, entropies, and free enthalpies obtained. With these data, the change of the crystallinity with temperature could be computed. In the early stages of solidification both compounds contain significant entropy contributions from conformational ordering of the flexible spacer and little from the rigid, aromatic segments. (C) 2000 John Wiley & Sons, Inc. 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 3 Z9 3 U1 0 U2 2 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 JAN 15 PY 2000 VL 38 IS 2 BP 319 EP 328 DI 10.1002/(SICI)1099-0488(20000115)38:2<319::AID-POLB4>3.0.CO;2-Z PG 10 WC Polymer Science SC Polymer Science GA 272UH UT WOS:000084669000004 ER PT J AU Baker, RD Schubert, G Jones, PW AF Baker, RD Schubert, G Jones, PW TI Convectively generated internal gravity waves in the lower atmosphere of Venus. Part I: No wind shear SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID COMPRESSIBLE CONVECTION; RADIO OCCULTATION; CLOUD AB This paper is the first of a two-part study that investigates internal gravity wave generation by convection in the lower atmosphere of Venus. A two-dimensional, nonlinear, fully compressible model of a perfect gas is employed. The calculations consider the lower atmosphere from 12- to 60-km altitude, thereby including two convection regions: the lower atmosphere convection layer from roughly 18- to 30-km altitude and the cloud-level convection layer from roughly 48- to 55-km altitude. The gravity waves of interest are located in the stable layer between these two convection regions. Part I of this study considers gravity wave generation and propagation in the absence of mean wind shear. In the absence of mean wind shear, internal gravity waves are primarily generated by cloud-level convection. Horizontal wavelengths (similar to 10-15 km) are similar to dominant horizontal scales in the cloud-level penetrative region, and intrinsic horizontal phase speeds are comparable to cloud-level downdraft velocities. Without mean wind shear, there is no effective coupling between the lower atmosphere below 34-km altitude and the overlying stable layer. Simulated wave amplitudes and vertical wavelengths agree well with spacecraft observations, suggesting that gravity waves generated by cloud-level convection through the "mechanical oscillator" effect may be responsible for observed variations in the stable layer. C1 Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90024 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA. RP Baker, RD (reprint author), NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Code 912, Greenbelt, MD 20771 USA. NR 39 TC 14 Z9 14 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD JAN 15 PY 2000 VL 57 IS 2 BP 184 EP 199 DI 10.1175/1520-0469(2000)057<0184:CGIGWI>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 276NX UT WOS:000084885300002 ER PT J AU Baker, RD Schubert, G Jones, PW AF Baker, RD Schubert, G Jones, PW TI Convectively generated internal gravity waves in the lower atmosphere of Venus. Part II: Mean wind shear and wave-mean flow interaction SO JOURNAL OF THE ATMOSPHERIC SCIENCES LA English DT Article ID COMPRESSIBLE CONVECTION; NUMERICAL EXPERIMENTS; RADIO OCCULTATION; SUPERROTATION; TURBULENCE; STRATOSPHERE; SIMULATIONS; SENSITIVITY; MAINTENANCE; ROTATION AB This paper is the second of a two-part study that numerically investigates internal gravity wave generation by convection in the lower atmosphere of Venus. Part I of this study considers gravity wave generation and propagation in the absence of mean wind shear. In Part II, the Venus westward superroration is included, and wave-mean flow interaction is assessed. Both lower-atmosphere convection and cloud-level convection play active roles in the dynamics of the stable layer from 31- to 47-km altitude when mean wind shear is present. This result contrasts with the simulation without mean wind shear presented in Part I where cloud-level collection was primarily responsible for gravity wave generation in the stable layer. In the presence of mean wind shear, upward entrainment from lower-atmosphere convection and downward penetration from cloud-level convection are comparable in magnitude. Convectively generated internal gravity waves have horizontal wavelengths (similar to 25-30 km) comparable to horizontal scales in both convection layers. Quasi-stationary gravity waves (with respect to the lower convection layer) occur in the lower part of the stable layer, while both eastward- and westward-propagating waves generated by cloud-level convection exist in the upper part of the stable layer. Simulated wave amplitudes and vertical wavelengths agree well with observations. Eastward-propagating waves generated by cloud-level convection experience critical level absorption in the stable layer and thus decelerate the Venus westward superrotation below the clouds. The deceleration is comparable in magnitude to zonal accelerations above the clouds by thermal tides. C1 Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA 90024 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90024 USA. RP Baker, RD (reprint author), NASA, Goddard Space Flight Ctr, Univ Space Res Assoc, Code 912, Greenbelt, MD 20771 USA. NR 38 TC 22 Z9 22 U1 0 U2 3 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0022-4928 J9 J ATMOS SCI JI J. Atmos. Sci. PD JAN 15 PY 2000 VL 57 IS 2 BP 200 EP 215 DI 10.1175/1520-0469(2000)057<0200:CGIGWI>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 276NX UT WOS:000084885300003 ER PT J AU Matsubara, I Paranthaman, M Allison, SW Cates, MR Beshears, DL Holcomb, DE AF Matsubara, I Paranthaman, M Allison, SW Cates, MR Beshears, DL Holcomb, DE TI Preparation of Cr-doped Y3Al5O12 phosphors by heterogeneous precipitation methods and their luminescent properties SO MATERIALS RESEARCH BULLETIN LA English DT Article DE optical materials; chemical synthesis; X-ray diffraction; luminescence ID YTTRIUM-ALUMINUM-GARNET; COMBUSTION PROCESS; POWDERS; YAG AB Chromium-doped Y3Al5O12 (YAG-Cr) phosphor powders were prepared by a heterogeneous precipitation method. Hydroxide precursor powders were precipitated from their respective metal sulfate solutions with urea. The formation of the YAG phosphors was investigated by means of XRD. Phase pure YAG-Cr was formed by heating the precursors at 1300 degrees C, which is more than 300 degrees C lower than that required for the conventional solid-state reaction method. The emission intensity of YAG-Cr phosphors increased with increasing firing temperature, and the intensities observed for phosphor powders were brighter than that of the commercial YAG-Cr phosphors. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Engn Technol Div, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Instrumentat & Controls Div, Oak Ridge, TN 37831 USA. RP Matsubara, I (reprint author), Osaka Natl Res Inst, 1-8-31 Midorigaoka, Ikeda, Osaka 563, Japan. RI Paranthaman, Mariappan/N-3866-2015; OI Paranthaman, Mariappan/0000-0003-3009-8531; Holcomb, David/0000-0001-8263-4661; Allison, Stephen/0000-0002-5887-5403 NR 22 TC 50 Z9 64 U1 0 U2 30 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0025-5408 J9 MATER RES BULL JI Mater. Res. Bull. PD JAN 15 PY 2000 VL 35 IS 2 BP 217 EP 224 DI 10.1016/S0025-5408(00)00202-6 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 320WK UT WOS:000087423700008 ER PT J AU Rawers, J AF Rawers, J TI Characterization of Fe-C-N alloys' mechanical properties SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE iron-carbon-nitrogen; hardness; strength; wear; microstructure ID IRON AB Melting a Fe-0.9wt.%C alloy under elevated nitrogen pressures produced carbide- and nitride-free alloys. The combination of high interstitial concentrations, approaching 2 wt.%, and duplex bcc-Fe/fcc-Fe microstructure resulted in alloys with compression yield strength in excess of 3 GPa while retaining over 20% ductility and with wear properties comparable to white cast irons. Statistical analysis showed a strong correlation between microstructure/nitrogen concentration and mechanical properties: hardness, strength, and wear. By the combination of both carbon and nitrogen, this process for the first time extended the interstitial concentration in iron to 2 wt.%. (C) 2000 Elsevier Science S.A. All rights reserved. C1 US DOE, Albany Res Ctr, Albany, OR 97321 USA. RP Rawers, J (reprint author), US DOE, Albany Res Ctr, 1450 Queens Ave, Albany, OR 97321 USA. NR 12 TC 2 Z9 2 U1 0 U2 3 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 JAN 15 PY 2000 VL 276 IS 1-2 BP 91 EP 98 DI 10.1016/S0921-5093(99)00521-3 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 271FH UT WOS:000084583200011 ER PT J AU Nicholson, JW Jasapara, J Rudolph, W Omenetto, FG Taylor, AJ AF Nicholson, JW Jasapara, J Rudolph, W Omenetto, FG Taylor, AJ TI Full-field characterization of femtosecond pulses by spectrum and cross-correlation measurements (vol 24, pg 1774, 99) SO OPTICS LETTERS LA English DT Correction C1 Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Nicholson, JW (reprint author), Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 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 JAN 15 PY 2000 VL 25 IS 2 BP 138 EP 138 DI 10.1364/OL.25.000138 PG 1 WC Optics SC Optics GA 274KA UT WOS:000084764000021 PM 18059808 ER PT J AU Rodriguez, MA Navrotsky, A Licci, F AF Rodriguez, MA Navrotsky, A Licci, F TI Thermochemistry of YBa2Cu3-xMxOy (M = Ni, Zn) SO PHYSICA C LA English DT Article DE thermochemistry; YBa2Cu3O7-delta; nickel; zinc; doping ID DOPANT-SITE OCCUPANCIES; BA-CU-O; DOPED YBA2CU3O7-DELTA; OXYGEN; SUBSTITUTION; SUPERCONDUCTIVITY; COPPER; DIFFRACTION; ENERGETICS; PEROVSKITE AB The partial molar enthalpy of incorporation of oxygen (Delta(ox) H) and enthalpy of formation (Delta(f) H) have been measured via high-temperature reaction calorimetry for YBa2Cu3-xMxOy (where M = Ni, Zn) in the composition range 0.0 < x < 0.18. Delta(ox) H and Delta(f) H values were nearly independent of dopant for both Ni and Zn, with enthalpies of oxidation in the range -86 to -110 kT/(mol 1/2O(2)) and enthalpies of formation in the range -110 to -118 kJ/mol. The independence of thermodynamic behavior from superconducting properties is consistent with an electronic mechanism for T-c suppression in Zn-doped YBCO superconductors. Oxygen contents, lattice parameters, and T-c measurements are also reported. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Davis, Thermochem Facil, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. CNR, Ist Mat Speciali Elettr & Magnetsimo, I-43010 Parma, Italy. RP Rodriguez, MA (reprint author), Sandia Natl Labs, POB 5800,MS 1405, Albuquerque, NM 87185 USA. NR 29 TC 14 Z9 14 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JAN 15 PY 2000 VL 329 IS 2 BP 88 EP 94 DI 10.1016/S0921-4534(99)00579-1 PG 7 WC Physics, Applied SC Physics GA 273EE UT WOS:000084694300003 ER PT J AU Vaknin, D Zarestky, JL Miller, LL AF Vaknin, D Zarestky, JL Miller, LL TI On the possibility of antiferromagnetic vortex cores in superconducting YBa2Cu3O7-delta SO PHYSICA C LA English DT Article DE superconductivity; antiferromagnetism; vortex core; YBa2Cu3O7 ID LA2CUO4 AB Neutron scattering studies of optimally doped single crystal YBa2Cu3O7-delta under applied magnetic field were used to assess the existence of antiferromagnetic (AF) correlations in vortices. In the superconducting (SC) state, a very weak signal at the (1/2 1/2 0) reciprocal lattice point was found. It is argued that this signal can be associated with AF correlations in vortex cores. An upper-limit average magnetic moment per vortex in each layer is estimated. Above T-c, weak paramagnetic scattering was observed, which we hypothesize is due to scattering from nearest-neighbor copper spins that are coupled ferromagnetically by a hole on an oxygen site between them. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Ames Lab, Dept Phys & Astron, Ames, IA 50011 USA. RP Vaknin, D (reprint author), Iowa State Univ, Ames Lab, Dept Phys & Astron, Ames, IA 50011 USA. RI Vaknin, David/B-3302-2009 OI Vaknin, David/0000-0002-0899-9248 NR 15 TC 16 Z9 16 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 JAN 15 PY 2000 VL 329 IS 2 BP 109 EP 113 DI 10.1016/S0921-4534(99)00558-4 PG 5 WC Physics, Applied SC Physics GA 273EE UT WOS:000084694300006 ER PT J AU Yang, CY Pashitski, A Polyanskii, A Larbalestier, DC Babcock, SE Goyal, A List, FA Park, C Paranthaman, M Norton, DP Lee, DF Kroeger, DM AF Yang, CY Pashitski, A Polyanskii, A Larbalestier, DC Babcock, SE Goyal, A List, FA Park, C Paranthaman, M Norton, DP Lee, DF Kroeger, DM TI Microstructural homogeneity and electromagnetic connectivity of YBa2Cu3O7-delta grown on rolling-assisted biaxially textured coated conductor substrates SO PHYSICA C LA English DT Article DE YBCO; coated conductors; RABiTS (TM); magneto optic imaging ID ELECTRON-BEAM EVAPORATION; CRITICAL-CURRENT DENSITY; BUFFER LAYERS; CURRENT FLOW; SUPERCONDUCTING TAPES; THICK-FILMS; NI; DEPOSITION; BOUNDARY; DEFECTS AB The electromagnetic connectivity and microstructure of three YBa2Cu3O7-delta (YBCO) films grown on biaxially textured substrates were investigated by magneto optic (MO) imaging and scanning electron microscopy (SEM). The films were deposited by pulsed laser deposition (PLD) on yttria-stabilized zirconia (YSZ) and CeO2-buffered, biaxially textured Ni tapes. The transport critical current density (J(c)) values of the films were 0.3, 0.6 and 0.7 MA/cm(2) (77 K, 0 T). MO imaging revealed clearly granular electromagnetic behavior in the lowest J(c) and one of the higher J(c) samples, but considerably better connectivity in the sample with a J(c) value of 0.6 MA/cm(2). High resolution SEM showed a dense and rather featureless microstructure in the YBCO of the most highly electromagnetically connected sample, whereas pores and/or second phase particles cluttered the YBCO layers of the granular samples. Thus, the granular behavior in these samples appears to be caused by pores and second phase particles that locally obstruct the superconducting current in the YBCO layer. Control of these types of defects clearly is important for raising the J(c) value. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Wisconsin, Ctr Appl Superconduct, Madison, WI 53706 USA. Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Babcock, SE (reprint author), Univ Wisconsin, Ctr Appl Superconduct, 1500 Engn Dr, Madison, WI 53706 USA. RI Polyanskii, Anatolii/B-8794-2009; Yoon, Sejin/F-7637-2013; Larbalestier, David/B-2277-2008; Paranthaman, Mariappan/N-3866-2015 OI Larbalestier, David/0000-0001-7098-7208; Paranthaman, Mariappan/0000-0003-3009-8531 NR 20 TC 9 Z9 9 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JAN 15 PY 2000 VL 329 IS 2 BP 114 EP 120 DI 10.1016/S0921-4534(99)00581-X PG 7 WC Physics, Applied SC Physics GA 273EE UT WOS:000084694300007 ER PT J AU Kaplan, T Liu, F Mostoller, M Chisholm, MF Milman, V AF Kaplan, T Liu, F Mostoller, M Chisholm, MF Milman, V TI First-principles study of impurity segregation in edge dislocations in Si SO PHYSICAL REVIEW B LA English DT Article ID GRAIN-BOUNDARIES; AB-INITIO AB Using ab initio calculations, the segregation of As, Ga, and Ge atoms in the core regions of perfect edge dislocations in Si is examined. When all nearest neighbors of an impurity are Si atoms, As favors the core site at maximum compression and has a segregation energy of 0.25 eV/atom. Ga and Ge impurities favor sites under maximum tension and have segregation energies of 0.44 and 0.19 eV per atom, respectively. For As impurities, however, a pairing mechanism yields an even larger segregation energy of 0.64 eV/atom. C1 Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Mol Simulat Ltd, Cambridge CB5 8RE, England. RP Kaplan, T (reprint author), Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. RI Milman, Victor/M-6117-2015 OI Milman, Victor/0000-0003-2258-1347 NR 10 TC 16 Z9 16 U1 1 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 JAN 15 PY 2000 VL 61 IS 3 BP 1674 EP 1676 DI 10.1103/PhysRevB.61.1674 PG 3 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200011 ER PT J AU Mahan, AH Yang, J Guha, S Williamson, DL AF Mahan, AH Yang, J Guha, S Williamson, DL TI Structural changes in a-Si : H film crystallinity with high H dilution SO PHYSICAL REVIEW B LA English DT Article ID AMORPHOUS-SILICON; HYDROGEN DILUTION; SOLAR-CELLS AB Using infrared absorption (ir) spectroscopy, H evolution, and x-ray diffraction (XRD), the structure of high-H-dilution, plasma-enhanced chemical vapor deposition a-Si:H films "on the edge of crystallinity" is examined. From the ir Si-H wag mode peak frequency and the XRD results, we postulate the existence of very small Si crystallites contained within the as-grown amorphous matrix with the majority of the bonded H located on these crystallite surfaces. Upon annealing, a low-temperature H-evolution peak appears, and film crystallization is observed at temperatures as low as 500 degrees C, which is far below that observed for a-Si:H films grown without H dilution. While the crystallite sizes and volume fraction are too small to be detected by XRD in the as-grown films, these crystallites catalyze the crystallization of the remainder of the amorphous matrix upon annealing, enabling the evolution of H at low temperatures. The large spatial inhomogeneity in the H bonding thus produced throughout the-film is suggested to be one of the reasons for the reduced Staebler-Wronski effect observed in solar cells utilizing these films. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. United Solar Syst Corp, Troy, MI 48084 USA. Colorado Sch Mines, Golden, CO 80401 USA. RP Mahan, AH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 24 TC 84 Z9 85 U1 1 U2 15 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 JAN 15 PY 2000 VL 61 IS 3 BP 1677 EP 1680 DI 10.1103/PhysRevB.61.1677 PG 4 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200012 ER PT J AU Harrison, N Cornelius, AL Harima, H Takegahara, K Detwiler, JA Schmiedeshoff, GM Cooley, JC Smith, JL AF Harrison, N Cornelius, AL Harima, H Takegahara, K Detwiler, JA Schmiedeshoff, GM Cooley, JC Smith, JL TI Electronic structure of ThBe13 SO PHYSICAL REVIEW B LA English DT Article ID FERMION SUPERCONDUCTOR UBE13; MAGNETOACOUSTIC QUANTUM OSCILLATIONS; METAMAGNETIC TRANSITION; MAGNETIC OSCILLATIONS; PHASE-TRANSITION; HEAVY FERMIONS; U1-XTHXBE13; DIAGRAM; SYSTEMS; METALS AB Angle-resolved de Haas-van Alphen measurements made on ThBe13 in pulsed magnetic fields are compared with Fermi surface predictions calculated by means of the linear augmented-plane-wave method with spin-orbit interactions. While all of the experimentally determined qustsiparticle effective masses are light and of order the free electron mass, they are still roughly double those obtained from the calculated band structure, thereby being suggestive of the existence of notable electron-phonon interactions. The relevance of these de Haas-van Alphen results to strongly correlated UBe13 is also discussed. C1 Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Osaka Univ, Inst Sci & Ind Res, Ibaraki, Osaka 5670047, Japan. Hirosaki Univ, Dept Mat Sci & Technol, Hirosaki, Aomori 0368561, Japan. Occidental Coll, Dept Phys, Los Angeles, CA 90041 USA. Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Harrison, N (reprint author), Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, MS-E536, Los Alamos, NM 87545 USA. RI Cornelius, Andrew/A-9837-2008; Cooley, Jason/E-4163-2013 NR 35 TC 5 Z9 5 U1 0 U2 8 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 JAN 15 PY 2000 VL 61 IS 3 BP 1779 EP 1785 DI 10.1103/PhysRevB.61.1779 PG 7 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200035 ER PT J AU Kelley, TM Beyermann, WP Robinson, RA Trouw, F Canfield, PC Nakotte, H AF Kelley, TM Beyermann, WP Robinson, RA Trouw, F Canfield, PC Nakotte, H TI Crystal-field spectrum and linewidths in the heavy-fermion system PrInAg2 SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-SCATTERING; Y1-XUXPD3; BEHAVIOR; UBE13 AB The heavy-fermion intermetallic compound PrInAg2 has been studied by means of inelastic neutron scattering. In agreement with a previous study, there is clear evidence from both the excitation energies and relative intensities that the crystal-electric-field ground state is the Gamma(3) nonmagnetic, non-Kramers doublet, and this, together with enhanced thermodynamic properties at low temperatures, indicates that PrInAg2 is a candidate quadrupolar Kondo material. In addition to the Gamma(3)-Gamma(4) and Gamma(3)-Gamma(5) excitations, which are seen at low temperature, we have observed the other two allowed transitions, Gamma(4)-Gamma(1), and Gamma(4)-Gamma(5), which are visible when the Gamma(4) triplet becomes thermally populated. Within the Lea-Leask-Wolf parametrization scheme, we obtain W = -0.111 +/- 0.006 meV and x = -0.079+/-0.037, values that are similar to but slightly different from those previously reported. No magnetic quasielastic scattering is seen, down to similar to 90 mu eV, and this provides further evidence that the heavy-fermion behavior is unconventional and has a nonmagnetic origin. However, bath the Gamma(3)-Gamma(4) and Gamma(3)-Gamma(5) levels are broadened significantly and to differing degrees. Possible sources of this broadening are discussed. C1 Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. Univ Calif Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Ames, IA 50011 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. RP Kelley, TM (reprint author), Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. RI Lujan Center, LANL/G-4896-2012; Canfield, Paul/H-2698-2014 NR 12 TC 16 Z9 16 U1 0 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 JAN 15 PY 2000 VL 61 IS 3 BP 1831 EP 1835 DI 10.1103/PhysRevB.61.1831 PG 5 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200042 ER PT J AU Hamalainen, K Hill, JP Huotari, S Kao, CC Berman, LE Kotani, A Ide, T Peng, JL Greene, RL AF Hamalainen, K Hill, JP Huotari, S Kao, CC Berman, LE Kotani, A Ide, T Peng, JL Greene, RL TI Polarization and momentum dependence of a charge-transfer excitation in Nd2CuO4 SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-SCATTERING; ABSORPTION; SPECTROSCOPY; SPECTRA AB We report the polarization and q dependence of 6-eV charge-transfer excitation in Nd2CuO4, as studied by resonant inelastic x-ray scattering. The incident polarization is shown to select the intermediate states participating in the resonant process, and resonances associated with 1s-->4p(sigma) and 1s-->4p(pi) transitions are resolved. No enhancement is observed for the 1s3d(10)L well-screened intermediate states in either case. Numerical calculations show that this is the result of nonlocal effects. The intensity and position of the excitation was found to be independent of the momentum transfer along the c axis for q = 3.5-7.9 Angstrom(-1). C1 Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. Univ Tokyo, Inst Solid State Phys, Minato Ku, Tokyo 106, Japan. Univ Maryland, Dept Phys & Astron, Ctr Superconduct Res, College Pk, MD 20742 USA. RP Hamalainen, K (reprint author), Univ Helsinki, Dept Phys, POB 9, FIN-00014 Helsinki, Finland. RI Hamalainen, Keijo/A-3986-2010; OI Hamalainen, Keijo/0000-0002-9234-9810; Huotari, Simo/0000-0003-4506-8722 NR 12 TC 39 Z9 39 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 JAN 15 PY 2000 VL 61 IS 3 BP 1836 EP 1840 DI 10.1103/PhysRevB.61.1836 PG 5 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200043 ER PT J AU Williamson, AJ Zunger, A AF Williamson, AJ Zunger, A TI Pseudopotential study of electron-hole excitations in colloidal free-standing InAs quantum dots SO PHYSICAL REVIEW B LA English DT Article ID SIZE; INP; SPECTROSCOPY; ENERGIES AB Excitonic spectra are calculated for free-standing, surface passivated, InAs quantum dots using atomic pseudopotentials for the single-particle states and screened Coulomb interactions for the two-body terms. We present an analysis of the single particle states involved in each excitation in terms of their angular momenta and Bloch-wave parentage. We find that (i) in agreement with other pseudopotential studies of CdSe and InP quantum dots, but in contrast to k . p calculations, the dot wave functions exhibit strong odd-even angular momentum envelope function mixing (e.g., s with p) and large valence-conduction coupling. (ii) While the pseudopotential approach produced very good agreement with experiment for free-standing, colloidal CdSe and InP dots, and for self-assembled (GaAs-embedded) InAs dots, here the predicted spectrum does not agree well with the measured (ensemble average over dot sizes) spectra. (1) Our calculated excitonic gap is larger than the photoluminescence measured one, and (2) while the spacing between the lowest excitons is reproduced, the spacings between higher excitons is not fit well. Discrepancy (1) could result from surface state emission. As for (2), agreement is improved when account is taken of the finite-size distribution in the experimental data. (iii) We find that the single-particle gap scales as R-1.01 (not R-2), that the screened (unscreened) electron-hole Coulomb interaction scales as R-1.79 (R-0.7), and that the excitonic gap scales as R-0.9. These scaling laws are different from those expected from simple models. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Williamson, AJ (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Zunger, Alex/A-6733-2013 NR 35 TC 75 Z9 75 U1 1 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 JAN 15 PY 2000 VL 61 IS 3 BP 1978 EP 1991 DI 10.1103/PhysRevB.61.1978 PG 14 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200065 ER PT J AU Primozich, N Shahbazyan, TV Perakis, IE Chemla, DS AF Primozich, N Shahbazyan, TV Perakis, IE Chemla, DS TI Coherent ultrafast optical dynamics of the Fermi-edge singularity SO PHYSICAL REVIEW B LA English DT Article ID SEMICONDUCTOR QUANTUM WELLS; 2-DIMENSIONAL ELECTRON-GAS; NONCANONICAL-TRANSFORMATION APPROACH; EXCITON-EXCITON CORRELATIONS; MANY-BODY; 4-WAVE-MIXING SIGNALS; VIRTUAL EXCITATION; HIGH-DENSITY; SPECTRA; HOLE AB We develop a nonequilibrium many-body theory of the coherent femtosecond nonlinear optical response of the Fermi-edge singularity. We study the role of the dynamical Fermi-sea response in the time evolution of the pump-probe spectra. The electron-hole correlations are treated nonperturbatively with the time-dependent coupled cluster expansion combined with the effective Hamiltonian approach. For shea pulse durations, we find a nonexponential decay of the differential transmission during negative time delays, which is governed by the interactions. This is in contrast to the results obtained within the Hartree-Fock approximation, which predicts an exponential decay governed by the dephasing time. We discuss the role of the: optically induced dephasing effects in the coherent regime. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Primozich, N (reprint author), Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RI Perakis, Ilias/G-9186-2011 NR 82 TC 33 Z9 33 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 JAN 15 PY 2000 VL 61 IS 3 BP 2041 EP 2058 DI 10.1103/PhysRevB.61.2041 PG 18 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200072 ER PT J AU Gupta, JA Watkins, SP Crozier, ED Woicik, JC Harrison, DA Jiang, DT Pickering, IJ Karlin, BA AF Gupta, JA Watkins, SP Crozier, ED Woicik, JC Harrison, DA Jiang, DT Pickering, IJ Karlin, BA TI Layer perfection in ultrathin InAs quantum wells in GaAs(001) SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-BEAM-EPITAXY; INDIUM SURFACE SEGREGATION; RAY STANDING-WAVE; ABSORPTION FINE-STRUCTURE; QUANTIZED LEVELS; ENERGY-LEVELS; GAAS; HETEROSTRUCTURES; MONOLAYER; INAS/GAAS AB X-ray standing wave (XSW), x-ray diffraction, and photoluminescence (PL) measurements were used to assess the layer perfection and positions of 1 and 1/2 monolayer (ML) InAs quantum wells buried in GaAs(001). Local structure in the 1-ML films was evaluated using x-ray absorption fine structure (XAFS) measurements. Growth temperature effects were studied in a series of samples produced by metal organic vapor phase epitaxy (MOVPE) between 400 and 600 degrees C. The XSW coherent position of the In atoms decreases With increasing temperature in the 1-ML samples, and the optimal growth temperature is near 550 degrees C, as evidenced by the coherent position of 1.15 +/- 0.02 and the relatively high coherent fraction of 0.72 +/- 0.08. With decreasing growth temperature the XSW measurements may suggest segregation of In atoms, which results in an incorporation of the In into multiple layers. The segregation appears to be reduced at the higher temperatures due to the favorable kinetic conditions created in the MOVPE environment. Low-temperature PL measurements indicate that the sharpest and most intense In-excitonic emission is obtained from the 1-ML sample grown at 530 degrees C. For the 1/2-ML samples, growth temperatures of 400 and 600 degrees C produce similar standing wave results, although the PL reveals the higher temperature sample to be of far superior quality, due to excessive carbon incorporation at 400 degrees C. In-As bond-length distortions found in the XAFS measurements agree with a macroscopic elastic description of the pseudomorphic epitaxy. C1 Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Gupta, JA (reprint author), Natl Res Council Canada, Inst Microstruct Sci, Ottawa, ON K1A 0R6, Canada. RI Pickering, Ingrid/A-4547-2013; OI Pickering, Ingrid/0000-0002-0936-2994 NR 44 TC 14 Z9 14 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 JAN 15 PY 2000 VL 61 IS 3 BP 2073 EP 2084 DI 10.1103/PhysRevB.61.2073 PG 12 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200075 ER PT J AU Wang, WK Simpson, WC Yarmoff, JA AF Wang, WK Simpson, WC Yarmoff, JA TI Reactions of I-2 and Cl-2 with In- and As-terminated InAs(001) SO PHYSICAL REVIEW B LA English DT Article ID SCANNING TUNNELING MICROSCOPY; 001 SURFACES; GAF3 FILMS; GAAS 110; ADSORPTION; GAAS(100); CHLORINE; IODINE; SPECTROSCOPY; PASSIVATION AB The reactions of I-2 and CI2 with InAs(001) were investigated with synchrotron-based soft-x-ray photoelectron spectroscopy and low-energy electron diffraction. I-2 saturates the In-terminated InAs(001) surface, forming a well-ordered overlayer of InI, while As-terminated InAs(001) becomes disordered and forms both In and As iodides. Both the In- and As-terminated surfaces are disordered by Cl-2 adsorption, forming InCl, InCl2, and As chlorides. The differences in the behavior of I-2 and Cl-2 are attributed primarily to the inability of InI2 to form on the outermost surface. C1 Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Yarmoff, JA (reprint author), Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. EM yarmoff@ucr.edu NR 37 TC 17 Z9 18 U1 1 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 JAN 15 PY 2000 VL 61 IS 3 BP 2164 EP 2172 DI 10.1103/PhysRevB.61.2164 PG 9 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200086 ER PT J AU Melechko, AV Braun, J Weitering, HH Plummer, EW AF Melechko, AV Braun, J Weitering, HH Plummer, EW TI Role of defects in two-dimensional phase transitions: An STM study of the Sn/Ge(111) system SO PHYSICAL REVIEW B LA English DT Article ID CHARGE-DENSITY-WAVE; RECONSTRUCTIONS; GE(111); SN AB The influence of Ge substitutional defects and vacancies on the (root 3 x root 3)-->(3 x 3) charge-density wave phase transition in the alpha phase of Sn on Ge(111) has been studied using a variable-temperature scanning tunneling microscope. Above 105 K, Ge substitutional defects stabilize regions with (3 x 3) symmetry that grow with decreasing temperature and can be described by a superposition of exponentially damped waves. At low temperatures, T less than or equal to 105 K defect-defect density-wave-mediated interactions force an alignment of the defects onto a honeycomb sublattice that supports the low-temperature (3 x 3) phase. This defect-mediated phase transition is completely reversible. The length scales involved in this defect-defect interaction dictate the domain size (approximate to 10(4) Angstrom(2)). C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Melechko, AV (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RI Melechko, Anatoli/B-8820-2008 NR 26 TC 71 Z9 71 U1 2 U2 16 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 JAN 15 PY 2000 VL 61 IS 3 BP 2235 EP 2245 DI 10.1103/PhysRevB.61.2235 PG 11 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200095 ER PT J AU Lu, ZY Wang, CZ Ho, KM AF Lu, ZY Wang, CZ Ho, KM TI Structures and dynamical properties of C-n, Si-n, Ge-n, and Sn-n clusters with n up to 13 SO PHYSICAL REVIEW B LA English DT Article ID INITIO MOLECULAR-DYNAMICS; SMALL SILICON CLUSTERS; CARBON CLUSTERS; SEMICONDUCTOR SURFACE; TEMPERATURE; PSEUDOPOTENTIALS; TRANSITION; GEOMETRIES; TRENDS AB Car-Parrinello molecular dynamics simulated annealings were carried out for clusters Si-n, Ge-n, and Sn-n (n less than or equal to 13). We investigate the temperature regions in which these clusters transform from a "liquidlike" phase to a "solidlike" phase, and then from the "solidlike" phase to the ground-state structures. Additional simulated annealing was also performed for the cluster C-13 which is selected as a prototype of small carbon clusters. In addition to the discovery of structures for Sn and Ge clusters, our simulation results also provide insights into the dynamics of cluster formation. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP US DOE, Ames Lab, Ames, IA 50011 USA. RI 上官, 敏慧/E-8964-2012 NR 40 TC 169 Z9 174 U1 1 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 JAN 15 PY 2000 VL 61 IS 3 BP 2329 EP 2334 DI 10.1103/PhysRevB.61.2329 PG 6 WC Physics, Condensed Matter SC Physics GA 291VW UT WOS:000085760200105 ER PT J AU Sales, BC Chakoumakos, BC Mandrus, D AF Sales, BC Chakoumakos, BC Mandrus, D TI Thermoelectric properties of thallium-filled skutterudites SO PHYSICAL REVIEW B LA English DT Article ID LATTICE THERMAL-CONDUCTIVITY; LAFE4P12 STRUCTURE; COSB3; ANTIMONIDES; TRANSPORT; CRYSTALS AB Crystallographic data, electrical and thermal transport measurements, and heat-capacity data are reported for several compounds with the filled skutterudite structure: TlxCo4-yFeySb12 and TlxCo4Sb12-ySny. where 0 <(x,y)< 1 and x approximate to y. These materials have potential use for thermoelectric power generation. The Tl atomic displacement parameters (ADP's) are large relative to the other elements in the compounds indicating substantial "rattling" of the Tl about its equilibrium position. A simple analysis of the ADP's and low-temperature heat-capacity data indicate an Einstein temperature for the Tl of 53+/-2 K. The resonant scattering of acoustic phonons by the Tl "rattlers" are believed to be the major cause of the rapid decrease in the lattice thermal conductivity as small amounts of Tl are inserted into the voids of the skutterudite structure. Thermal and electrical transport are investigated as a function of the void filling with monovalent Tl and they are compared to previous data reported for partial filling with trivalent rare;earth ions. For comparable filling fractions, the Tl compounds had higher electron mobilities and a similar depression of the thermal conductivity. Unlike the rare-earth skutterudites, however, within experimental error there was no evidence of mass-fluctuation scattering and the minimum thermal conductivity occurred near complete void filling. Ar elevated temperatures (800 K), the maximum thermoelectric figure of merit, ZT, for n-type samples is estimated from room-temperature data to be about 0.8 for both Tl-filled and rare-earth-filled Co4Sb12. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Sales, BC (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Mandrus, David/H-3090-2014; Chakoumakos, Bryan/A-5601-2016 OI Chakoumakos, Bryan/0000-0002-7870-6543 NR 33 TC 235 Z9 247 U1 10 U2 62 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 JAN 15 PY 2000 VL 61 IS 4 BP 2475 EP 2481 DI 10.1103/PhysRevB.61.2475 PG 7 WC Physics, Condensed Matter SC Physics GA 284TJ UT WOS:000085348300023 ER PT J AU Taguchi, M Parlebas, JC Uozumi, T Kotani, A Kao, CC AF Taguchi, M Parlebas, JC Uozumi, T Kotani, A Kao, CC TI Kappa beta resonant x-ray emission spectra in MnF2 SO PHYSICAL REVIEW B LA English DT Article ID ABSORPTION-SPECTROSCOPY; INCOMPLETE SHELL; CORE ELECTRONS; NICKEL COMPOUNDS; OPTICAL-SPECTRA; CE COMPOUNDS; PHOTOEMISSION; FLUORESCENCE; METALS; SCATTERING AB We report experimental and theoretical results on Mn K beta resonant x-ray emission spectra (K beta RXES) at the pre-edge region of K-edge x-ray absorption spectroscopy in a powdered MnF2 sample. The experimental results are studied theoretically in terms of coherent second-order optical process, using a MnF6-4 cluster model with the effects of intra-atomic multiplet coupling and interatomic hybridization in the space of three configurations and taking into account both the Mn 1s-3d quadrupole excitation and the Mn 1s-4p dipole excitation. The agreement between theory and experiment is good. Moreover, we show that if the sample is a single crystal the resonant x-ray emission spectroscopy caused by the quadrupole excitation has a strong sensitivity to the angle of the incident photon. C1 CNRS, IPCMS, GEMM, F-67037 Strasbourg, France. Univ Osaka Prefecture, Coll Engn, Sakai, Osaka 593, Japan. Univ Tokyo, Inst Solid State Phys, Minato Ku, Tokyo 106, Japan. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Taguchi, M (reprint author), CNRS, IPCMS, GEMM, 23 Rue Loess, F-67037 Strasbourg, France. NR 35 TC 31 Z9 31 U1 0 U2 4 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 JAN 15 PY 2000 VL 61 IS 4 BP 2553 EP 2560 DI 10.1103/PhysRevB.61.2553 PG 8 WC Physics, Condensed Matter SC Physics GA 284TJ UT WOS:000085348300032 ER PT J AU Soderlind, P Yang, LH Moriarty, JA Wills, JM AF Soderlind, P Yang, LH Moriarty, JA Wills, JM TI First-principles formation energies of monovacancies in bcc transition metals SO PHYSICAL REVIEW B LA English DT Article ID VACANCY-FORMATION ENERGIES; ELECTRONIC-STRUCTURE; TUNGSTEN; SYSTEMS; SURFACES; FCC AB Monovacancies for seven bcc d-transition metals V, Cr, Fe, Nb, Mo, Ta, and W have been studied in detail from first-principles calculations. A full-potential, linear muffin-tin-orbital (FP-LMTO) method has been used in conjunction with both the local-density approximation (LDA) and the generalized-gradient approximation (GGA) to calculate volume-relaxed vacancy formation energies in all seven metals. A complementary ab initio pseudopotential (PP) method has been used to calculate both volume- and structure-relaxed LDA formation energies and formation volumes in V, Nb, Mo, Ta, and W. Fully relaxed PP geometries have also been applied to FP-LMTO LDA and GGA calculations. From these results, the following clear trends and conclusions emerge: (i) for the same fully relaxed geometry, FP-LMTO-LDA and PP-LDA formation energies are nearly identical; (ii) the lowest calculated formation energies are within or close to experimental error bars for all bcc metals except Cr, and the overall agreement with experiment is better for the 4d and 5d metals than the 3d metals; (iii) GGA and LDA formation energies are very similar for the 4d and 5d metals but for the 3d metals, and especially Fe, GGA performs better; (iv) volume- and structural-relaxation contributions lower the calculated formation energy by 0.1-0.5 eV, and improve agreement with experiment; (v) fully relaxed LDA formation volumes are in the narrow range (0.45-0.62)Omega(0), where Omega(0) is the equilibrium atomic volume; and (vi) the dominant structural effects are an approximate 5% inward relaxation of the first near-neighbor shell for group-V metals and a corresponding 1% inward relaxation for group-VI metals, with the exception of Mo, for which the second-shell atoms also relax inward by about 1%. C1 Lawrence Livermore Natl Lab, Phys Directorate, Livermore, CA 94551 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87544 USA. RP Lawrence Livermore Natl Lab, Phys Directorate, POB 808, Livermore, CA 94551 USA. NR 38 TC 78 Z9 79 U1 1 U2 26 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 JAN 15 PY 2000 VL 61 IS 4 BP 2579 EP 2586 DI 10.1103/PhysRevB.61.2579 PG 8 WC Physics, Condensed Matter SC Physics GA 284TJ UT WOS:000085348300034 ER PT J AU Yang, WD Lee, H Johnson, TJ Sercel, PC Norman, AG AF Yang, WD Lee, H Johnson, TJ Sercel, PC Norman, AG TI Electronic structure of self-organized InAs/GaAs quantum dots bounded by {136} facets SO PHYSICAL REVIEW B LA English DT Article ID STRAIN DISTRIBUTION; INAS ISLANDS; GAAS; PHOTOLUMINESCENCE; LUMINESCENCE; INGAAS; MODEL; RELAXATION; MICROSCOPY; ENERGY AB Recent experiments indicate that the shape of self-organized InAs quantum dots grown on GaAs [001] is an elongated pyramid with bounding facets corresponding to a family of four {136} planes. This structure, which possesses C-2v Symmetry, is quite different from square-base pyramidal or lens geometries, which, have been assumed in previous electronic structure calculations for this system. In this paper, we consider theoretically the influence of the {136} shape on the electronic structure and optical properties of the quantum dots. We present a valence force-field calculation of the inhomogeneous strain and incorporate the results into an eight band (k) over right arrow.(p) over right arrow electronic structure calculation. The size dependence of the electronic structure is calculated and compared to experimental photoluminescence spectra. The effects of perturbations on the {136} shape are also considered. Calculations based on the {136} shape give good agreement with the observed level structure and optical polarization properties of self-organized InAs/GaAs quantum dots. C1 Univ Oregon, Dept Phys, Eugene, OR 97403 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Univ Oregon, Dept Phys, Eugene, OR 97403 USA. RI Norman, Andrew/F-1859-2010 OI Norman, Andrew/0000-0001-6368-521X NR 49 TC 47 Z9 48 U1 2 U2 4 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 JAN 15 PY 2000 VL 61 IS 4 BP 2784 EP 2793 DI 10.1103/PhysRevB.61.2784 PG 10 WC Physics, Condensed Matter SC Physics GA 284TJ UT WOS:000085348300061 ER PT J AU Bogicevic, A Ovesson, S Lundqvist, BI Jennison, DR AF Bogicevic, A Ovesson, S Lundqvist, BI Jennison, DR TI Atom-by-atom and concerted hopping of adatom pairs on an open metal surface SO PHYSICAL REVIEW B LA English DT Article ID DIFFUSION; EXCHANGE; APPROXIMATIONS; DYNAMICS; SOLIDS AB Atom-by-atom and concerted hopping of ad-dimers on the open (100) surface of fee metals are studied by means of density-functional calculations. The adatom interaction is relatively short ranged, and beyond next-nearest neighbors ad-dimers are effectively dissociated. Diffusion takes place by a simple shearing process, favored because it maximizes adatom coordination at the transition state. This holds for Al, Au, and Rh, and is likely a general result because geometrical arguments dominate over details of the electronic structure. C1 Sandia Natl Labs, Surface & Interface Sci Dept, Albuquerque, NM 87185 USA. Chalmers, Dept Appl Phys, S-41296 Gothenburg, Sweden. Univ Gothenburg, S-41296 Gothenburg, Sweden. RP Sandia Natl Labs, Surface & Interface Sci Dept, POB 5800, Albuquerque, NM 87185 USA. RI Lundqvist, Bengt/A-9013-2011 NR 23 TC 7 Z9 7 U1 0 U2 0 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 JAN 15 PY 2000 VL 61 IS 4 BP R2456 EP R2459 DI 10.1103/PhysRevB.61.R2456 PG 4 WC Physics, Condensed Matter SC Physics GA 284TJ UT WOS:000085348300018 ER PT J AU Feibelman, PJ AF Feibelman, PJ TI Ordering of self-diffusion barrier energies on Pt(110)-(1x2) SO PHYSICAL REVIEW B LA English DT Article ID ABINITIO MOLECULAR-DYNAMICS; WAVE BASIS-SET; ULTRASOFT PSEUDOPOTENTIALS; METALS; TRANSITION; SIMULATION AB Bond-counting arguments, supported by ab initio calculations, predict a lower barrier for "leapfrog" diffusion of Pt ad-dimers on Pt(110)-1 x 2 than for adatom diffusion or ad-dimer dissociation. This conflicts with experiment, possibly signalling contaminant influence. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 21 TC 20 Z9 20 U1 0 U2 3 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 JAN 15 PY 2000 VL 61 IS 4 BP R2452 EP R2455 DI 10.1103/PhysRevB.61.R2452 PG 4 WC Physics, Condensed Matter SC Physics GA 284TJ UT WOS:000085348300017 ER PT J AU Muramatsu, Y Grush, MM Perera, RCC AF Muramatsu, Y Grush, MM Perera, RCC TI Resonant elastic x-ray scattering of graphite and diamond at the carbon K threshold SO PHYSICAL REVIEW B LA English DT Article ID UNDULATOR RADIATION; FLUORESCENCE; EMISSION AB Resonant elastic x-ray scattering (REXS) was observed at the carbon K threshold of graphite powder, and a small amount of excitonic x-ray scattering was observed in diamond. A comparison of the energy spectra of REXS in graphite with the carbon K x-ray absorption spectra, and with the calculated energy spectra of the unoccupied density of states, suggests that REXS is caused by the transition of the ''participator'' electrons via p pi* states in sp(2)-carbon atoms. The probabilities of transition to "participator" REXS or to "spectator" resonant inelastic x-ray scattering in the resonant radiative-decay process of graphite powder, were determined from REXS spectroscopy to be approximately 47% and 53%, respectively. C1 NTT, Lifestyle & Environm Technol Labs, Musashino, Tokyo 1808585, Japan. Univ Tennessee, Knoxville, TN 37996 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RP Muramatsu, Y (reprint author), NTT, Lifestyle & Environm Technol Labs, Musashino, Tokyo 1808585, Japan. NR 14 TC 2 Z9 2 U1 1 U2 4 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 JAN 15 PY 2000 VL 61 IS 4 BP R2393 EP R2396 DI 10.1103/PhysRevB.61.R2393 PG 4 WC Physics, Condensed Matter SC Physics GA 284TJ UT WOS:000085348300002 ER PT J AU Csaki, C Skiba, W Terning, J AF Csaki, C Skiba, W Terning, J TI beta functions of orbifold theories and the hierarchy problem SO PHYSICAL REVIEW D LA English DT Article ID QUANTUM-FIELD THEORY; RENORMALIZATION-GROUP EQUATIONS; GAUGE-THEORIES; CHIRAL HIERARCHIES; QUADRATIC DIVERGENCES; TECHNICOLOR THEORIES; SYMMETRY-BREAKING; LIGHT DILATION; COUPLINGS; SCALE AB We examine a class of gauge theories obtained by projecting out certain fields from an N=4 supersymmetric SU(N) gauge theory. These theories are non-supersymmetric and in the large N limit are known to be conformal. Recently it was proposed that the hierarchy problem could be solved by embedding the standard model in a theory of this kind with finite N. In order to check this claim one must find the conformal points of the theory. To do this we calculate the one-loop beta functions for the Yukawa and quartic scalar couplings. We find that with the beta functions set to zero the one-loop quadratic divergences are not canceled at sub-leading order in N; thus the hierarchy between the weak scale and the Planck scale is not stabilized unless N is of the order 10(28) or larger. We also find that at sub-leading orders in N renormalization induces new interactions, which were not present in the original Lagrangian. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Csaki, C (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM csaki@lanl.gov; skiba@einstein.ucsd.edu; terning@schwinger.harvard.edu NR 52 TC 27 Z9 27 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 JAN 15 PY 2000 VL 61 IS 2 AR 025019 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 276BK UT WOS:000084855600082 ER PT J AU Csaki, C Shirman, Y AF Csaki, C Shirman, Y TI Brane junctions in the Randall-Sundrum scenario SO PHYSICAL REVIEW D LA English DT Article ID COSMOLOGICAL CONSTANT PROBLEM; DOMAIN-WALLS; DIMENSIONS; SUPERGRAVITY; TEV; MILLIMETER; SPACETIME AB We present static solutions to Einstein's equations corresponding to branes at various angles intersecting in a single 3-brane. Such configurations may be useful for building models with localized gravity via the Randall-Sundrum mechanism. We find that such solutions may exist only if the mechanical forces acting on the junction exactly cancel. In addition to this constraint there are further conditions that the parameters of the theory have to satisfy. We find that at least one of these involves only the brane tensions and cosmological constants, and thus cannot have a dynamical origin. We present these conditions in detail for two simple examples. We discuss the nature of the cosmological constant problem in the framework of these scenarios, and outline the desired features of the brane configurations which may bring us closer towards a resolution of the cosmological constant problem. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA. RP Csaki, C (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div T8, POB 1663, Los Alamos, NM 87545 USA. EM ccsaki@lbl.gov; yuri@feynman.princeton.edu NR 36 TC 60 Z9 60 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 JAN 15 PY 2000 VL 61 IS 2 AR 024008 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 276BK UT WOS:000084855600032 ER PT J AU Habib, S Molina-Paris, C Mottola, E AF Habib, S Molina-Paris, C Mottola, E TI Energy-momentum tensor of particles created in an expanding universe SO PHYSICAL REVIEW D LA English DT Article ID QUANTUM-FIELD-THEORY; DE-SITTER SPACE; ADIABATIC REGULARIZATION; SCALAR FIELD; BLACK-HOLE; INFLATIONARY-UNIVERSE; POINT-SEPARATION; CURVED SPACETIME; GRAVITY-WAVES; BACK-REACTION AB We present a general formulation of the time-dependent initial value problem for a quantum scalar field of arbitrary mass and curvature coupling in a Friedmann-Robertson-Walker (FRW) cosmological model. We introduce an adiabatic number basis which has the virtue that the divergent parts of the quantum expectation value of the energy-momentum tensor (T-ab) are isolated in the vacuum piece of (T-ab), and may be removed using adiabatic subtraction. The resulting renormalized (T-ab) is conserved, independent of the cutoff, and has a physically transparent, quasiclassical form in terms of the average number of created adiabatic "particles." By analyzing the evolution of the adiabatic particle number in de Sitter spacetime we exhibit the time structure of the particle creation process, which can be understood in terms of the time at which different momentum scales enter the horizon. A numerical scheme to compute (T-ab) as a function of time with arbitrary adiabatic initial states (not necessarily de Sitter invariant) is described. For minimally coupled, massless fields, at late times the renormalized (T-ab) goes asymptotically to the de Sitter invariant state previously found by Alien and Folacci, and not to the zero mass limit of the Bunch-Davies vacuum. If the mass m and the curvature coupling xi differ from zero, but satisfy m(2) + xi R = 0, the energy density and pressure of the scalar field grow linearly in cosmic time demonstrating that, at least in this case, back reaction effects become significant and cannot be neglected in de Sitter spacetime. C1 Univ Calif Los Alamos Natl Lab, Theoret Div T8, Los Alamos, NM 87545 USA. RP Habib, S (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div T8, POB 1663, Los Alamos, NM 87545 USA. EM habib@lanl.gov; carmen@t6-serv.lanl.gov; emil@lanl.gov NR 79 TC 34 Z9 34 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 JAN 15 PY 2000 VL 61 IS 2 AR 024010 PG 22 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 276BK UT WOS:000084855600034 ER PT J AU Kachru, S McGreevy, J AF Kachru, S McGreevy, J TI Supersymmetric three-cycles and (super)symmetry breaking SO PHYSICAL REVIEW D LA English DT Article ID FIELD-THEORIES; BPS STATES; D-BRANES; STRINGS; MANIFOLDS; ALGEBRAS AB We describe physical phenomena associated with a class of transitions that occur in the study of supersymmetric three-cycles in Calabi-Yau (CY) threefolds. The transitions in question occur at real codimension one in the complex structure moduli space of the Calabi-Yau manifold. In type-IIB string theory, these transitions can be used to describe the evolution of a Bogomol'nyi-Prasad-Sommerfeld (BPS) state as one moves through a locus of marginal stability: at the transition point the BPS particle becomes degenerate with a supersymmetric two-particle state, and after the transition the lowest energy state carrying the same charges is a nonsupersymmetric two-particle state. In the IIA theory, wrapping the cycles in question with D6 branes leads to a simple realization of the Fayet model: for some values of the CY modulus gauge symmetry is spontaneously broken: while for other values supersymmetry is spontaneously broken. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Kachru, S (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. EM skachru@leland.stanford.edu; mcgreevy@socrates.berkeley.edu NR 22 TC 79 Z9 79 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JAN 15 PY 2000 VL 61 IS 2 AR 026001 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 276BK UT WOS:000084855600083 ER PT J AU Singh, A Srednicki, M AF Singh, A Srednicki, M TI Quantum kinetic equations and dark matter abundances reconsidered SO PHYSICAL REVIEW D LA English DT Article ID DECAY AB Starting from a Caldeira-Leggett model for the interaction of a system with an environment, Joichi, Matsumoto, and Yoshimura have reconsidered the derivation of the quantum Boltzmann equation. They find an extra term that accounts for the effects of virtual particles, and which drastically changes the results for relic densities of stable, weakly interacting massive particles and for the decay products of unstable particles. We show, however, that this modified Boltzmann equation does not properly account for the interaction energy between the massive particles (which are decaying or annihilating) and the thermal hath of light particles. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. RP Singh, A (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, T-8, Los Alamos, NM 87545 USA. EM singh@lanl.gov; mark@physics.ucsb.edu NR 8 TC 7 Z9 7 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 JAN 15 PY 2000 VL 61 IS 2 AR 023509 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 276BK UT WOS:000084855600014 ER PT J AU Srivastava, PP Brodsky, SJ AF Srivastava, PP Brodsky, SJ TI Light-front-quantized QCD in a covariant gauge SO PHYSICAL REVIEW D LA English DT Article ID INFINITE-MOMENTUM FRAME; QUANTUM ELECTRODYNAMICS; CONE QUANTIZATION; FIELD-THEORY; RENORMALIZATION; MODEL AB The light-front (LF) canonical quantization of quantum chromodynamics in covariant gauges is discussed. The Dirac procedure is used to eliminate the constraints in the gauge-fixed front form theory quantum action and to construct the LF Hamiltonian formulation. The physical degrees of freedom emerge naturally. The propagator of the dynamical psi(+), part of the free fermionic propagator in the LF quantized field theory is shown to be causal and not to contain instantaneous terms. Since the relevant propagators in the covariant gauge formulation are causal, rotational invariance-including the Coulomb potential in the static limit-can be recovered, avoiding the difficulties encountered in light-cone gauge. Wick rotation may also be performed allowing the conversion of momentum space integrals into Euclidean space forms. Some explicit computations are done in quantum electrodynamics to illustrate the equivalence of front form theory with the conventional covariant formulation. LF quantization thus provides a consistent formulation of gauge theory, despite the fact that the hyperplanes x(+/-)=0 used to impose boundary conditions constitute characteristic surfaces of a hyperbolic partial differential equation. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Srivastava, PP (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM prem@slac.stanford.edu; sjbth@slac.stanford.edu NR 41 TC 23 Z9 23 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 JAN 15 PY 2000 VL 61 IS 2 AR 025013 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 276BK UT WOS:000084855600076 ER PT J AU Norsworthy, G Leidholm, CR Halani, A Kapur, VK Roe, R Basol, BM Matson, R AF Norsworthy, G Leidholm, CR Halani, A Kapur, VK Roe, R Basol, BM Matson, R TI CIS film growth by metallic ink coating and selenization SO SOLAR ENERGY MATERIALS AND SOLAR CELLS LA English DT Article DE photovoltaics; thin-film; solar cells AB A novel technique was demonstrated for the growth of CuInSe2 (CIS) thin films. The technique used an ink formulation containing sub-micron size particles of Cu-In alloys. A metallic precursor layer was first formed by coating this ink onto the substrate by spraying. The precursor film was then made to react with Se to form the CIS compound. The morphology of the CIS layers depended on the initial composition of the Cu-In particles as well as the post-deposition treatments. Solar cells were fabricated on CIS absorber layers prepared by this low-cost ink-coating approach and devices with a conversion efficiency of over 10.5% were demonstrated. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Int Solar Elect Technol Inc, ISET, Inglewood, CA 90301 USA. NREL, Golden, CO 80401 USA. RP Norsworthy, G (reprint author), Int Solar Elect Technol Inc, ISET, 8635 Aviat Blvd, Inglewood, CA 90301 USA. NR 11 TC 57 Z9 71 U1 1 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0248 J9 SOL ENERG MAT SOL C JI Sol. Energy Mater. Sol. Cells PD JAN 15 PY 2000 VL 60 IS 2 BP 127 EP 134 DI 10.1016/S0927-0248(99)00075-6 PG 8 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 262XZ UT WOS:000084094700003 ER PT J AU Ford, JV Sumpter, BG Noid, DW Barnes, MD AF Ford, JV Sumpter, BG Noid, DW Barnes, MD TI Observation of size oscillations in poly(ethylene) glycol/electrolyte composite microparticles SO CHEMICAL PHYSICS LETTERS LA English DT Article ID POLYMER ELECTROLYTES; SCATTERING; PARTICLES AB Two-dimensional optical diffraction in polymer/electrolyte composite microparticles has revealed interesting structural/morphological dynamics that occur on a time scale of several minutes. In addition to its utility as a qualitative probe of material homogeneity and phase-separation behavior in composite systems, PEG/NaCl particles probed by optical diffraction exhibit particle size oscillation (up to 100 nanometers peak-to-peak). The specific behavior observed depends on the concentration and nature of the electrolyte in the PEG host particle. These results demonstrate the feasibility of 2-D angular scattering in polymer composite particles as a means for probing structural phase transitions in ultrasmall (10-500 femtoliters) confined volumes. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Opt Spect Grp, Oak Ridge, TN 37831 USA. RP Barnes, MD (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Opt Spect Grp, POB 2008,Bldg 4500S,MS 6142, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 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 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 14 PY 2000 VL 316 IS 3-4 BP 181 EP 185 DI 10.1016/S0009-2614(99)01332-9 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 276PY UT WOS:000084887600002 ER PT J AU Cumings, J Zettl, A AF Cumings, J Zettl, A TI Mass-production of boron nitride double-wall nanotubes and nanococoons SO CHEMICAL PHYSICS LETTERS LA English DT Article ID CARBON NANOTUBES; STABILITY AB Various techniques including plasma-are, laser ablation, and chemical vapor-phase synthesis have been employed to produce bulk amounts of non-carbon (such as boron nitride, BN) nanotubes with some success, but in general the yields are low. We describe a new high-yield plasma-are method that easily and reliably produces macroscopic amounts of pure BN nanotubes. Interestingly, the method produces almost exclusively double-walled nanotubes; these in turn self-assemble into BN nanotube bundles or ropes. Our synthesis method also produces BN-coated crystalline nanoparticles, whose cores can be preferentially etched leaving behind hollow BN 'nanococoons'. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Zettl, A (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Cumings, John/A-3595-2012; Zettl, Alex/O-4925-2016 OI Zettl, Alex/0000-0001-6330-136X NR 18 TC 185 Z9 187 U1 3 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 14 PY 2000 VL 316 IS 3-4 BP 211 EP 216 DI 10.1016/S0009-2614(99)01277-4 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 276PY UT WOS:000084887600007 ER PT J AU Noid, DW Fukui, K Sumpter, BG Yang, C Tuzun, RE AF Noid, DW Fukui, K Sumpter, BG Yang, C Tuzun, RE TI Time-averaged normal coordinate analysis of polymer particles and crystals SO CHEMICAL PHYSICS LETTERS LA English DT Article ID MOLECULAR MECHANICS CALCULATIONS; DYNAMICS SIMULATIONS; POLYETHYLENE; SYSTEMS AB A common problem in the application of normal coordinate analysis to study low-frequency modes of large molecular systems is the occurrence of a large number of negative eigenvalues (unstable modes). By averaging the terms of the Hessian matrix over a short classical trajectory, the unstable modes were found to be completely eliminated for 6000 atom model polymer particles and crystals. The time-averaged matrices were made possible by an efficient analytical formulation of the Cartesian second derivatives and diagonalization was achieved using a sparse matrix solver (ARPACK). (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. SUNY Brockport, Computat Sci Program, Brockport, NY 14420 USA. RP Noid, DW (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 31 TC 18 Z9 18 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 14 PY 2000 VL 316 IS 3-4 BP 285 EP 296 DI 10.1016/S0009-2614(99)01152-5 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 276PY UT WOS:000084887600018 ER PT J AU Sakash, JB Chan, RS Tsuruta, H Kantrowitz, ER AF Sakash, JB Chan, RS Tsuruta, H Kantrowitz, ER TI Three of the six possible intersubunit stabilizing interactions involving Glu-239 are sufficient for restoration of the homotropic and heterotropic properties of Escherichia coli aspartate transcarbamoylase SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID SITE-DIRECTED MUTAGENESIS; REGULATORY CHAIN; CATALYTIC CHAIN; CARBAMOYLTRANSFERASE; MODEL; COOPERATIVITY; PURIFICATION; REPLACEMENT; RESOLUTION; PROTEINS AB A hybrid version of Escherichia coli aspartate transcarbamoylase was investigated in which one catalytic subunit has the wild-type sequence, and the other catalytic subunit has Glu-239 replaced by Gln, Since Glu-239 is involved in intersubunit interactions, this hybrid could be used to evaluate the extent to which T state stabilization is required for homotropic cooperativity and for heterotropic effects. Reconstitution of the hybrid holoenzyme (two different catalytic subunits with three wild-type regulatory subunits) was followed by separation of the mixture by anion-exchange chromatography. To make possible the resolution of the three holoenzyme species formed by the reconstitution, the charge of one of the catalytic subunits was altered by the addition of six aspartic acid residues to the C terminus of each of the catalytic chains (AT-C catalytic subunit). Control experiments indicated that the AT-C catalytic subunit as well as the holoenzyme formed with AT-C and wild-type regulatory subunits had essentially the same homotropic and heterotropic properties as the native catalytic subunit and holoenzyme, indicating that the addition of the aspartate tail did not influence the function of either enzyme. The control reconstituted holoenzyme, in which both catalytic subunits have Glu-239 replaced by Gln, exhibited no cooperativity, an enhanced affinity for aspartate, and essentially no heterotropic response identical to the enzyme isolated without reconstitution. The hybrid containing one normal and one mutant catalytic subunit exhibited homotropic cooperativity with a Hill coefficient of 1.4 and responded to the nucleotide effecters at about 50% of the level of the wild-type enzyme. Small angle x-ray scattering experiments with the hybrid enzyme indicated that in the absence of ligands it was structurally similar, but not identical, to the T state of the wild-type enzyme. In contrast to the wild-type enzyme, addition of carbamoyl phosphate induced a significant alteration in the scattering pattern, whereas the bisubstrate analog N-phosphonoacetyl-L-aspartate induced a significant change in the scattering pattern indicating the transition to the R-structural state. These data indicate that in the hybrid enzyme only three of the usual six interchain interactions involving Glu-239 are sufficient to stabilize the enzyme in a low affinity, low activity state and allow an allosteric transition to occur. C1 Boston Coll, Merkert Chem Ctr, Dept Chem, Chestnut Hill, MA 02467 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Kantrowitz, ER (reprint author), Boston Coll, Merkert Chem Ctr, Dept Chem, Chestnut Hill, MA 02467 USA. FU NCRR NIH HHS [P41RR01209]; NIGMS NIH HHS [GM26237] NR 36 TC 17 Z9 17 U1 0 U2 1 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 JAN 14 PY 2000 VL 275 IS 2 BP 752 EP 758 DI 10.1074/jbc.275.2.752 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 275TQ UT WOS:000084836600008 PM 10625604 ER PT J AU Goto, JJ Zhu, HN Sanchez, RJ Nersissian, A Gralla, EB Valentine, JS Cabelli, DE AF Goto, JJ Zhu, HN Sanchez, RJ Nersissian, A Gralla, EB Valentine, JS Cabelli, DE TI Loss of in vitro metal ion binding specificity in mutant copper-zinc superoxide dismutases associated with familial amyotrophic lateral sclerosis SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID PULSE-RADIOLYSIS; HYDROGEN-PEROXIDE; TYROSINE NITRATION; K-M; ALS; SITE; CHAPERONE; MECHANISM; PEROXYNITRITE; AGGREGATION AB The presence of the copper ion at the active site of human wild type copper-zinc superoxide dismutase (CuZnSOD) is essential to its ability to catalyze the disproportionation of superoxide into dioxygen and hydrogen peroxide, Wild type CuZnSOD and several of the mutants associated with familial amyotrophic lateral sclerosis (FALS) (Ala(4) --> Val, Gly(93) --> Ala, and Leu(38) --> Val) were expressed in Saccharomyces cerevisiae, Purified metal-free (apoproteins) and various remetallated derivatives were analyzed by metal titrations monitored by UV-visible spectroscopy, histidine modification studies using diethylpyrocarbonate, and enzymatic activity measurements using pulse radiolysis. From these studies it was concluded that the FALS mutant CuZnSOD apoproteins, in direct contrast to the human wild type apoprotein, have lost their ability to partition and bind copper and zinc ions in their proper locations in vitro, Similar studies of the wild type and FALS mutant CuZnSOD holoenzymes in the "as isolated" metallation state showed abnormally low copper-to-zinc ratios, although all of the copper acquired was located at the native copper binding sites. Thus, the copper ions are properly directed to their native binding sites in vivo, presumably as a result of the action of the yeast copper chaperone Lys7p (yeast CCS), The loss of metal ion binding specificity of FALS mutant CuZnSODs in vitro may be related to their role in ALS. C1 Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Valentine, JS (reprint author), Univ Calif Los Angeles, Dept Chem & Biochem, Box 951569, Los Angeles, CA 90095 USA. RI Zhu, Haining/A-6076-2008; Valentine, Joan/B-6665-2008 OI Valentine, Joan/0000-0002-7174-925X FU NIGMS NIH HHS [GM28222] NR 47 TC 124 Z9 125 U1 2 U2 6 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 JAN 14 PY 2000 VL 275 IS 2 BP 1007 EP 1014 DI 10.1074/jbc.275.2.1007 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 275TQ UT WOS:000084836600043 PM 10625639 ER PT J AU Mott, JD Thomas, CL Rosenbach, MT Takahara, K Greenspan, DS Banda, MJ AF Mott, JD Thomas, CL Rosenbach, MT Takahara, K Greenspan, DS Banda, MJ TI Post-translational proteolytic processing of procollagen C-terminal proteinase enhancer releases a metalloproteinase inhibitor SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID HUMAN TISSUE INHIBITOR; BONE MORPHOGENETIC PROTEIN-1; CAPILLARY ENDOTHELIAL-CELLS; ALPHA-1-PROTEINASE INHIBITOR; NEUTROPHIL CHEMOATTRACTANT; MATRIX METALLOPROTEINASES; EXPRESSION; TIMP-1; IDENTIFICATION; GLYCOPROTEIN AB Activity of matrix metalloproteinases (MMP) is regulated by a family of proteins called tissue inhibitors of metalloproteinases (TIMP). Four TIMPs have been cloned, and their molecular weights range from 29,000 to 20,000. By reverse zymography, we have observed a metalloproteinase inhibitor with an apparent molecular weight of 16,500 from medium conditioned by human brain tumor cells. Antibodies directed against TIMPs failed to react with the 16,500 molecular weight inhibitor, indicating that it was not a truncated form of a known TIMP. The inhibitor was isolated from conditioned medium using affinity and ion exchange chromatography, N-terminal sequences of the inhibitor matched amino acid sequences within the C-terminal domain of a protein known as procollagen C-terminal proteinase enhancer (PCPE), Thus, the inhibitor was named CT-PCPE. Comparison of the N-terminal domain of TIMP with CT-PCPE revealed that both contained six cysteine residues. As in the case of TIMP, reduction and alkylation abolished the inhibitory activity of CT-PCPE. Purified CT-PCPE inhibited MMP-2 with an IC50 value much greater than that of TIMP-2, This implies that MMPs may not be the physiologic targets for CT-PCPE inhibition. However, these results suggest that CT-PCPE may constitute a new class of metalloproteinase inhibitor. C1 Univ Calif San Francisco, Dept Radiol, San Francisco, CA 94143 USA. Univ Wisconsin, Dept Pathol & Lab Med, Madison, WI 53706 USA. Univ Wisconsin, Dept Biomol Chem, Madison, WI 53706 USA. RP Mott, JD (reprint author), Lawrence Berkeley Nat Lab, Mail Stop 74-157, Berkeley, CA 94720 USA. OI Greenspan, Daniel/0000-0001-8096-7446 FU NIAMS NIH HHS [AR43621]; NIEHS NIH HHS [T32-ES07106]; NIGMS NIH HHS [GM46846] NR 44 TC 87 Z9 89 U1 0 U2 0 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 JAN 14 PY 2000 VL 275 IS 2 BP 1384 EP 1390 DI 10.1074/jbc.275.2.1384 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 275TQ UT WOS:000084836600093 PM 10625689 ER PT J AU Miyabe, K Guiochon, G AF Miyabe, K Guiochon, G TI Kinetic study of the mass transfer of bovine serum albumin in anion-exchange chromatography SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE kinetic studies; mass transfer; anion exchangers; diffusion coefficients; albumin ID PERFORMANCE LIQUID-CHROMATOGRAPHY; STRONGLY BASIC CHITOSAN; CONCENTRATION-DEPENDENCE; SURFACE-DIFFUSION; PROTEIN ADSORPTION; CELLULOSE TRIACETATE; LIGHT-SCATTERING; ACTIVATED CARBON; PORE DIFFUSION; ION-EXCHANGERS AB A kinetic study was made on the mass transfer phenomena of bovine serum albumin (BSA) in two different anion-exchange columns (Resource-Q and TSK-GEL-DEAE-5PW). The analysis of the concentration dependence of the lumped mass transfer rate coefficient (k(m,L)) provided the information about the kinetics of the several mass transfer processes in the columns and the anion exchangers, i.e., the axial dispersion, the fluid-to-particle mass transfer, the intraparticle diffusion,and the adsorption/desorption. In the Resource-Q column, the intraparticle diffusion had a dominant contribution to the band broadening compared with those of the other processes. The surface diffusion coefficient (D-s) Of BSA showed a positive concentration dependence, by which the linear dependence of k(m,L) on the BSA concentration seemed to be interpreted On the other hand, in the TSK-GEL-DEAE-5PW column, the contribution of the adsorption/desorption was also important and almost same as that due to the intraparticle diffusion. There are some differences between the intrinsic properties of the mass transfer kinetics inside the two anion exchangers. It was likely that the positive concentration dependence of D-s was explained by the heterogeneous surface model. (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 Guiochon, G (reprint author), Univ Tennessee, Dept Chem, 611 Buehler Hall, Knoxville, TN 37996 USA. NR 54 TC 57 Z9 57 U1 0 U2 7 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 JAN 14 PY 2000 VL 866 IS 2 BP 147 EP 171 DI 10.1016/S0021-9673(99)01127-9 PG 25 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 274RE UT WOS:000084778200001 PM 10670806 ER PT J AU Wang, Y Espenson, JH AF Wang, Y Espenson, JH TI Oxidation of symmetric disulfides with hydrogen peroxide catalyzed by methyltrioxorhenium(VII) SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID METHYLRHENIUM TRIOXIDE; ESTERS AB Organic disulfides with both alkyl and aryl substituents are oxidized by hydrogen peroxide when CH3ReO3 (MTO) is used as a catalyst. The first step of the reaction is complete usually in about an hour, at which point the thiosulfinate, RS(O)SR, can be detected in nearly quantitative yield. The thiosulfinate is then converted, also by MTO-catalyzed oxidation under these conditions, to the thiosulfonate and, over long periods, to sulfonic acids, RSO3H. In the absence of excess peroxide, RS(O)SR (R = p-tolyl), underwent disproportionation to RS(O)(2)SR and RSSR. Kinetics studies of the first oxidation reaction established that two peroxorhenium compounds are the active forms of the catalyst, CH3ReO2(eta(2)-O-2) (A) and CH3ReO(eta(2)-O-2)(2).(OH2) (B) Their reactivities are similar; typical rate constants (L mol(-1) s(-1), 25 degrees C, aqueous acetonitrile) are k(A) = 22, k(B) = 150 (Bu2S2) and k(A) = 1.4, k(B) = 11 (Tol(2)S(2)) An analysis of the data for (p-XC6H4)(2)S-2 by a plot of log k(B) against the Hammett sigma constant gave rho = -1.89, supporting a mechanism in which the electron-rich sulfur attacks a peroxo oxygen of intermediates A and B. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 25 TC 29 Z9 29 U1 3 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD JAN 14 PY 2000 VL 65 IS 1 BP 104 EP 107 DI 10.1021/jo991109w PG 4 WC Chemistry, Organic SC Chemistry GA 275JD UT WOS:000084816300016 ER PT J AU Kukk, E Bozek, JD Sheehy, JA Langhoff, PW Berrah, N AF Kukk, E Bozek, JD Sheehy, JA Langhoff, PW Berrah, N TI Angular distribution of molecular-field- and spin-orbit-split sulfur 2p photoemission in OCS: a sensitive probe of the molecular environment SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Letter ID PHOTOELECTRON-SPECTROSCOPY; AUGER SPECTRUM; HCL; PHOTOIONIZATION; H2S AB Angle-resolved sulfur 2p photoelectron spectra from the OCS molecule are reported in very high electron and photon energy resolution. The measurements reveal significant differences in the angular distributions of ejected electrons associated with different core-level ionic multiplet states. A concomitant theoretical analysis relates these data to the perturbing effects of spinorbit and molecular-field splittings, and indicates that the measured angular distributions in high resolution provide a new and sensitive probe of the molecular body-frame environment in the absence of explicit sample alignment. C1 Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. USAF, Res Lab, AFRL, PRS, Edwards AFB, CA 93524 USA. Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. RP Kukk, E (reprint author), Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. RI Bozek, John/E-4689-2010; Bozek, John/E-9260-2010 OI Bozek, John/0000-0001-7486-7238 NR 21 TC 16 Z9 16 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD JAN 14 PY 2000 VL 33 IS 1 BP L51 EP L57 DI 10.1088/0953-4075/33/1/107 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 282VA UT WOS:000085239200007 ER PT J AU Haschke, JM Allen, TH Morales, LA AF Haschke, JM Allen, TH Morales, LA TI Reaction of plutonium dioxide with water: Formation and properties of PuO2+x SO SCIENCE LA English DT Article AB Results show that PuO2-x, a high-composition (x less than or equal to 0.27) phase containing Pu(VI), is the stable binary oxide in air, This nonstoichiometric oxide forms by reaction of dioxide with water and by water-catalyzed reaction of dioxide with oxygen. The PuO2 + H2O reaction rate is 0.27 nanomoles per meter squared per hour at 25 degrees C; the activation energy at 25 degrees to 350 degrees C is 39 kilojoules per mole. Slow kinetics and a Low Lattice parameter-composition dependence for fluorite-related PuO2+x are consistent with a failure to observe the phase in earlier studies. Perplexing aspects of plutonium oxide chemistry can now be explained. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Haschke, JM (reprint author), 11003 Willow Bend Dr, Waco, TX 76712 USA. NR 23 TC 147 Z9 148 U1 6 U2 52 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 14 PY 2000 VL 287 IS 5451 BP 285 EP 287 DI 10.1126/science.287.5451.285 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 274ML UT WOS:000084769600033 ER PT J AU Wang, XB Ferris, K Wang, LS AF Wang, XB Ferris, K Wang, LS TI Photodetachment of gaseous multiply charged anions, copper phthalocyanine tetrasulfonate tetraanion: Tuning molecular electronic energy levels by charging and negative electron binding SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID GAS-PHASE; PHOTOELECTRON-SPECTROSCOPY; DIELECTRIC POLARIZABILITY; ION-SOURCE; CHEMISTRY; CLUSTERS; DISSOCIATION; IONIZATION; HYDRATION AB We report photodetachment photoelectron :spectroscopy (PES) of gaseous copper phthalocyanine (CuPc) tetrasulfonate quadruply charged anions, [CUPC(SO3)(4)](4-), and its monoprotonated and -sodiumated triply charged anions, [CuPc(SO3)(4)H](3-) and [CuPc(SO3)(4)Na](3-). The [CUPC(So(3))(4)](4-) tetraanion was found to possess a negative electron binding energy of -0.9 eV, whereas-the trianions have binding energies of 1.0 and 1.2 eV for the sodiumated and protonated species; respectively. The PES spectral features of the three multiply charged anions were observed to be similar to that of the parent CuPc neutral molecule, except that the anions have lower binding energies due to the presence of the negative charges (-SO3-). The data thus suggested a stepwise tuning of the molecular electronic energy levels of the CuPc molecule through charging, wherein the molecular orbital energies of the parent molecule were systematically pushed up by the negative charges. We further carried out semiempirical calculations, which provided insight into the nature of the localized charges on the peripheral -SO3- groups and the intramolecular electrostatic interactions in the multiply charged anions and confirmed the interpretation of the stepwise tuning of molecular energy levels by charging. Photon energy-dependent studies revealed, the effects of the repulsive Coulomb barriers on the photodetachment PES spectra of the multiply charged anions. The barrier heights were estimated to be about 3.5 and 2.5 eV for the tetra- and trianions, respectively.: We also observed excited states for the multiply charged anions and resonant tunneling through the:repulsive Coulomb barriers via the excited states. C1 Pacific NW Lab, Dept Mat Sci, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Washington State Univ, Dept Phys, Richland, WA 99352 USA. RP Ferris, K (reprint author), Pacific NW Lab, Dept Mat Sci, MS K2-44,POB 999, Richland, WA 99352 USA. NR 48 TC 43 Z9 43 U1 0 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 13 PY 2000 VL 104 IS 1 BP 25 EP 33 DI 10.1021/jp9930090 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 283BR UT WOS:000085256700003 ER PT J AU Bai, S Palmer, BJ Yonker, CR AF Bai, S Palmer, BJ Yonker, CR TI Kinetics of deuterium exchange on resorcinol in D2O at high pressure and high temperature SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID IN-SITU NMR; SUPERCRITICAL WATER; RAMAN-SPECTROSCOPY; HYDROGEN-BONDS; METHANOL; OXIDATION; FLOW; CONVERSION; REACTIVITY AB The kinetics of deuteration of resorcinol in pure D2O were studied for the first time using a flow-through capillary tubular reactor with on-line, proton, and deuterium NMR detection at high temperatures and high pressure. The global rate constants for hydrogen/deuterium (H/D) exchange were determined from temperatures of 200-450 degrees C (723 K) at a pressure of similar to 400 bar (the critical temperature and pressure of water are 374.2 degrees C and 218.3 bar, respectively). The H/D exchange rate in resorcinol (1,3-dihydroxybenzene) under these extreme conditions was determined using proton NMR as a function of the resorcinol residence time in a capillary tubular reactor, which also served as a high-pressure NMR cell. The H-1 and H-2 NMR results indicate that H/D exchange in resorcinol for the ring protons was observed at temperatures as low as 200 degrees C. The kinetics of H/D exchange in resorcinol and the activation energy was extracted from the experimental H-1 NMR data. C1 Pacific NW Natl Lab, Environm & Energy Sci Div, Richland, WA 99352 USA. RP Yonker, CR (reprint author), Pacific NW Natl Lab, Environm & Energy Sci Div, Richland, WA 99352 USA. NR 37 TC 14 Z9 15 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JAN 13 PY 2000 VL 104 IS 1 BP 53 EP 58 DI 10.1021/jp991192r PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 283BR UT WOS:000085256700006 ER PT J AU Pichot, F Gregg, BA AF Pichot, F Gregg, BA TI The photovoltage-determining mechanism in dye-sensitized solar cells SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Letter ID MODULATED PHOTOCURRENT SPECTROSCOPY; NANOCRYSTALLINE TIO2 ELECTRODES; DIMENSIONAL ONSAGER MODEL; PHOTOELECTROCHEMICAL CELLS; POTENTIAL DISTRIBUTION; SEMICONDUCTOR-FILMS; TRANSPORT; INJECTION; CONVERSION; SEPARATION AB We attempt to distinguish between two competing models of the photovoltage-determining mechanism in dye-sensitized solar cells. One model does not consider the equilibrium potential difference at the TiO2/substrate interface to be a significant factor in determining the photovoltage; the other claims that this potential difference sets the upper limit to the achievable photovoltage. We deposit dye-sensitized TiO2 films on four different substrates that have vacuum work functions spanning a 1.4 eV range and measure the photovoltage obtained from these films in three different redox electrolyte solutions. No significant differences in photovoltage are obtained on the different substrates, not even on Pt where the interfacial potential should oppose electron transfer. We suggest that the interfacial potential barrier may be smaller than expected and/or too thin to have a significant influence on cell performance. We conclude that the photovoltage is determined by photoinduced chemical potential gradients, not by equilibrium electric fields. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Gregg, BA (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 35 TC 115 Z9 119 U1 3 U2 18 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 JAN 13 PY 2000 VL 104 IS 1 BP 6 EP 10 DI 10.1021/jp993035y PG 5 WC Chemistry, Physical SC Chemistry GA 283BJ UT WOS:000085256000002 ER PT J AU Groves, JT Boxer, SG McConnell, HM AF Groves, JT Boxer, SG McConnell, HM TI Electric field effects in multicomponent fluid lipid membranes SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID PLANAR SUPPORTED BILAYERS; INDUCED CONCENTRATION GRADIENTS; PHOSPHOLIPID-BILAYERS; BROWNIAN-MOTION; MONOLAYERS; PROTEINS; SURFACE; CELLS AB A thermodynamic model of multicomponent fluid membranes under the influence of lateral forces is described. Membrane components are characterized by their effective molecular areas, molecular charges, and the set of critical demixing coefficients (differential interaction energies) between each of the different species present. This model is useful in the analysis of electric field induced concentration gradients in supported lipid bilayer membranes; It has been employed to determine the critical temperature for spontaneous lateral phase separation of a mixture of cardiolipin and phosphatidylcholine from field-induced concentration profiles of a fluorescent probe. More generally, it provides a convenient way of interpreting critical demixing effects in multicomponent membranes and exploring the way these influence the response of a membrane to lateral forces. C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Acad Sinica, Inst Chem, Taipei, Taiwan. RP Boxer, SG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. NR 37 TC 18 Z9 18 U1 1 U2 12 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 JAN 13 PY 2000 VL 104 IS 1 BP 119 EP 124 DI 10.1021/jp992340g PG 6 WC Chemistry, Physical SC Chemistry GA 283BJ UT WOS:000085256000016 ER PT J AU Breitweg, J Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Pellegrino, A Repond, J Stanek, R Yoshida, R Mattingly, MCK Abbiendi, G Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Coppola, N Corradi, M De Pasquale, S Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Hartmann, H Heinloth, K Hilger, E Jakob, HP Kappes, A Katz, UF Kerger, R Paul, E Rautenberg, J Schnurbusch, H Stifutkin, A Tandler, J Voss, KC Weber, A Wieber, H Bailey, DS Barret, O Brook, NH Foster, B Heath, GP Heath, HF McFall, JD Piccioni, D Rodrigues, E Scott, J Tapper, RJ Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Liu, W Liu, X Mellado, B Sacchi, R Sampson, S Sciulli, F Chwastowski, J Eskreys, A Figiel, J Klimek, K Olkiewicz, K Przybycien, MB Stopa, P Zawiejski, L Adamczyk, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Kotanski, A Bauerdick, LAT Behrens, U Bienlein, JK Burgard, C Desler, K Drews, G Fox-Murphy, A Fricke, U Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hasell, D Hebbel, K Johnson, KF Kasemann, M Koch, W Kotz, U Kowalski, H Lindemann, L Lohr, B Martinez, M Milite, M Monteiro, T Moritz, M Notz, D Pelucchi, F Petrucci, MC Piotrzkowski, K Rohde, M Saull, PRB Savin, AA Schneekloth, U Selonke, F Sievers, M Stonjek, S Tassi, E Wolf, G Wollmer, U Youngman, C Zeuner, W Coldewey, C Grabosch, HJ Viani, ALD Meyer, A Schlenstedt, S Straub, PB Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Raach, H Wolfle, S Bussey, PJ Doyle, AT Lee, SW Macdonald, N McCance, GJ Saxon, DH Sinclair, LE Skillicorn, IO Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Garfagnini, A Gialas, I Gladilin, LK Kcira, D Klanner, R Lohrmann, E Poelz, G Zetsche, F Goncalo, R Long, KR Miller, DB Tapper, AD Walker, R Mallik, U Wang, SM Cloth, P Filges, D Ishii, T Kuze, M Nagano, K Tokushuku, K Yamada, S Yamazaki, Y Ahn, SH An, SH Hong, SJ Lee, SB Nam, SW Park, SK Lim, H Park, IH Son, D Barreiro, F Garcia, G Glasman, C Gonzalez, O Labarga, L del Peso, J Redondo, I Terron, J Barbi, M Corriveau, F Hanna, DS Ochs, A Padhi, S Riveline, M Stairs, DG Wing, M Tsurugai, T Bashkirov, V Dolgoshein, BA Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Velthuis, JJ Verkerke, W Vossebeld, J Wiggers, L de Wolf, E Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Boogert, S Cooper-Sarkar, AM Devenish, RCE Grosse-Knetter, J Matsushita, T Ruske, O Sutton, MR Walczak, R Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dondana, S Dosselli, U Dusini, S Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Iannotti, L Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Cormack, C Hart, JC McCubbin, NA Shah, TP Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Pavel, N Abramowicz, H Dagan, S Kananov, S Kreisel, A Levy, A Abe, T Fusayasu, T Umemori, K Yamashita, T Hamatsu, R Hirose, T Inuzuka, M Kitamura, S Nishimura, T Arneodo, M Cartiglia, N Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Ruspa, M Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, D Butterworth, JM Catterall, CD Hayes, ME Heaphy, EA Jones, TW Lane, JB West, BJ Ciborowski, J Ciesielski, R Grzelak, G Nowak, RJ Pawlak, JM Pawlak, R Smalska, B Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Gadaj, T Deppe, O Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Foudas, C Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wildschek, T Wodarczyk, M Deshpande, A Dhawan, S Hughes, VW Bhadra, S Cole, JE Frisken, WR Hall-Wilton, R Khakzad, M Menary, S Schmidke, WB AF Breitweg, J Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Pellegrino, A Repond, J Stanek, R Yoshida, R Mattingly, MCK Abbiendi, G Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Coppola, N Corradi, M De Pasquale, S Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Hartmann, H Heinloth, K Hilger, E Jakob, HP Kappes, A Katz, UF Kerger, R Paul, E Rautenberg, J Schnurbusch, H Stifutkin, A Tandler, J Voss, KC Weber, A Wieber, H Bailey, DS Barret, O Brook, NH Foster, B Heath, GP Heath, HF McFall, JD Piccioni, D Rodrigues, E Scott, J Tapper, RJ Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Liu, W Liu, X Mellado, B Sacchi, R Sampson, S Sciulli, F Chwastowski, J Eskreys, A Figiel, J Klimek, K Olkiewicz, K Przybycien, MB Stopa, P Zawiejski, L Adamczyk, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Kotanski, A Bauerdick, LAT Behrens, U Bienlein, JK Burgard, C Desler, K Drews, G Fox-Murphy, A Fricke, U Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hasell, D Hebbel, K Johnson, KF Kasemann, M Koch, W Kotz, U Kowalski, H Lindemann, L Lohr, B Martinez, M Milite, M Monteiro, T Moritz, M Notz, D Pelucchi, F Petrucci, MC Piotrzkowski, K Rohde, M Saull, PRB Savin, AA Schneekloth, U Selonke, F Sievers, M Stonjek, S Tassi, E Wolf, G Wollmer, U Youngman, C Zeuner, W Coldewey, C Grabosch, HJ Viani, ALD Meyer, A Schlenstedt, S Straub, PB Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Raach, H Wolfle, S Bussey, PJ Doyle, AT Lee, SW Macdonald, N McCance, GJ Saxon, DH Sinclair, LE Skillicorn, IO Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Garfagnini, A Gialas, I Gladilin, LK Kcira, D Klanner, R Lohrmann, E Poelz, G Zetsche, F Goncalo, R Long, KR Miller, DB Tapper, AD Walker, R Mallik, U Wang, SM Cloth, P Filges, D Ishii, T Kuze, M Nagano, K Tokushuku, K Yamada, S Yamazaki, Y Ahn, SH An, SH Hong, SJ Lee, SB Nam, SW Park, SK Lim, H Park, IH Son, D Barreiro, F Garcia, G Glasman, C Gonzalez, O Labarga, L del Peso, J Redondo, I Terron, J Barbi, M Corriveau, F Hanna, DS Ochs, A Padhi, S Riveline, M Stairs, DG Wing, M Tsurugai, T Bashkirov, V Dolgoshein, BA Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Velthuis, JJ Verkerke, W Vossebeld, J Wiggers, L de Wolf, E Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Boogert, S Cooper-Sarkar, AM Devenish, RCE Grosse-Knetter, J Matsushita, T Ruske, O Sutton, MR Walczak, R Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dondana, S Dosselli, U Dusini, S Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Iannotti, L Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Cormack, C Hart, JC McCubbin, NA Shah, TP Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Pavel, N Abramowicz, H Dagan, S Kananov, S Kreisel, A Levy, A Abe, T Fusayasu, T Umemori, K Yamashita, T Hamatsu, R Hirose, T Inuzuka, M Kitamura, S Nishimura, T Arneodo, M Cartiglia, N Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Ruspa, M Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, D Butterworth, JM Catterall, CD Hayes, ME Heaphy, EA Jones, TW Lane, JB West, BJ Ciborowski, J Ciesielski, R Grzelak, G Nowak, RJ Pawlak, JM Pawlak, R Smalska, B Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Gadaj, T Deppe, O Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Foudas, C Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wildschek, T Wodarczyk, M Deshpande, A Dhawan, S Hughes, VW Bhadra, S Cole, JE Frisken, WR Hall-Wilton, R Khakzad, M Menary, S Schmidke, WB CA ZEUS Collaboration TI Measurement of inclusive prompt photon photoproduction at HERA SO PHYSICS LETTERS B LA English DT Article ID CENTRAL TRACKING DETECTOR; JET CROSS-SECTIONS; PARTON DISTRIBUTIONS; HARD SCATTERING; MONTE-CARLO; ZEUS; CONSTRUCTION; CALORIMETER; PROTON; DESIGN AB First inclusive measurements of isolated prompt photons in photoproduction at the HERA ep collider have been made with the ZEUS detector, using an integrated luminosity of 38.4 pb(-1) Cross sections are given as a funct ion of the pseudorapidity and the transverse energy (eta(gamma) , E-T(gamma)) of the photon for E-1(gamma) > 5 GeV in thr gamma p centre-of-mass energy ranee 133-285 GeV. Comparisons are made with predictions from Monte Carlo models having Icading-logarithm pal-ton showers, and with next-to-leading-order QCD calculations, using currently available parameterisations of the photon structure. For forward eta(gamma) (proton direction) good agreement is found, but in the rear direction all predictions fall below the data. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Andrews Univ, Berrien Springs, MI 49104 USA. Univ Bologna, Bologna, Italy. Ist Nazl Fis Nucl, I-40126 Bologna, Italy. Univ Bonn, Inst Phys, D-5300 Bonn, Germany. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Univ Calabria, Dept Phys, I-87036 Cosenza, Italy. Ist Nazl Fis Nucl, I-87036 Cosenza, Italy. Chonnam Natl Univ, Kwangju, South Korea. Columbia Univ, Nevis Labs, Irvington, NY USA. Inst Nucl Phys, Krakow, Poland. Acad Min & Met, Fac Phys & Nucl Tech, Krakow, Poland. Jagiellonian Univ, Dept Phys, Krakow, Poland. DESY, D-2000 Hamburg, Germany. DESY, Zeuthen, Germany. Univ Florence, Florence, Italy. Ist Nazl Fis Nucl, I-50125 Florence, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Freiburg, Fak Phys, D-7800 Freiburg, Germany. Univ Glasgow, Dept Phys & Astron, Glasgow, Lanark, Scotland. Univ Hamburg, Inst Expt Phys 1, Hamburg, Germany. Univ Hamburg, Inst Expt Phys 2, D-2000 Hamburg, Germany. Univ London Imperial Coll Sci Technol & Med, High Energy Nucl Phys Grp, London, England. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Forschungszentrum Julich, Inst Kernphys, Julich, Germany. KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki, Japan. Korea Univ, Seoul 136701, South Korea. Kyungpook Natl Univ, Taegu 702701, South Korea. Univ Autonoma Madrid, Dept Fis Teor, Madrid, Spain. McGill Univ, Dept Phys, Montreal, PQ H3A 2T5, Canada. Meiji Gakuin Univ, Fac Gen Educ, Yokohama, Kanagawa, Japan. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow, Russia. NIKHEF H, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, Amsterdam, Netherlands. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Oxford, Dept Phys, Oxford, England. Univ Padua, Dipartimento Fis, Padua, Italy. Ist Nazl Fis Nucl, Padua, Italy. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Polytech Univ, Sagamihara, Kanagawa, Japan. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Rome, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Univ Siegen, Fachbereich Phys, D-5900 Siegen, Germany. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys, IL-69978 Tel Aviv, Israel. Univ Tokyo, Dept Phys, Tokyo 113, Japan. Tokyo Metropolitan Univ, Dept Phys, Tokyo, Japan. Univ Turin, Dipartimento Fis Sperimentale, Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Turin, Fac Sci 2, Turin, Italy. Ist Nazl Fis Nucl, Alessandria, Italy. Univ Toronto, Dept Phys, Toronto, ON, Canada. UCL, Dept Phys & Astron, London, England. Warsaw Univ, Inst Phys Expt, Warsaw, Poland. Inst Nucl Studies, PL-00681 Warsaw, Poland. Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. York Univ, Dept Phys, Toronto, ON M3J 2R7, Canada. IROE, Florence, Italy. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI dusini, stefano/J-3686-2012; Goncalo, Ricardo/M-3153-2016; De Pasquale, Salvatore/B-9165-2008; Wing, Matthew/C-2169-2008; Bashkirov, Vladimir/A-4818-2008; Solomin, Anatoly/C-3072-2016; Doyle, Anthony/C-5889-2009; Golubkov, Yury/E-1643-2012; Proskuryakov, Alexander/J-6166-2012; Katz, Uli/E-1925-2013; Wiggers, Leo/B-5218-2015; Tassi, Enrico/K-3958-2015; Gladilin, Leonid/B-5226-2011; Morandin, Mauro/A-3308-2016 OI dusini, stefano/0000-0002-1128-0664; Goncalo, Ricardo/0000-0002-3826-3442; Bailey, David C/0000-0002-7970-7839; Kasemann, Matthias/0000-0002-0429-2448; Castellini, Guido/0000-0002-0177-0643; Arneodo, Michele/0000-0002-7790-7132; Abbiendi, Giovanni/0000-0003-4499-7562; De Pasquale, Salvatore/0000-0001-9236-0748; Doyle, Anthony/0000-0001-6322-6195; Katz, Uli/0000-0002-7063-4418; Wiggers, Leo/0000-0003-1060-0520; Gladilin, Leonid/0000-0001-9422-8636; Morandin, Mauro/0000-0003-4708-4240 NR 39 TC 51 Z9 51 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD JAN 13 PY 2000 VL 472 IS 1-2 BP 175 EP 188 DI 10.1016/S0370-2693(99)01450-1 PG 14 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 278QU UT WOS:000085001100027 ER PT J AU Subramanian, G Hjelm, RP Deming, TJ Smith, GS Li, Y Safinya, CR AF Subramanian, G Hjelm, RP Deming, TJ Smith, GS Li, Y Safinya, CR TI Structure of complexes of cationic lipids and poly(glutamic acid) polypeptides: A pinched lamellar phase SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID OPPOSITELY CHARGED SURFACTANTS; DNA-LIPOSOME COMPLEXES; GENE-TRANSFER; STOICHIOMETRIC COMPLEXES; SYNTHETIC POLYPEPTIDES; NEUTRON-SCATTERING; SOLID-STATE; THERAPY; MULTIMEMBRANE; EXPRESSION AB Complexes of cationic lipids with negatively charged biological polyelectrolytes such as DNA and proteins have elicited much interest recently because of their potential applications in gene delivery and in developing novel biomolecular materials. We report on the structure of complexes made from the anionic polypeptide poly-L-glutamic acid (PGA) and a positively charged lipid mixture consisting of the cationic lipid didodecyl dimethylammonium bromide (DDAB) and the neutral lipid dilauroyl-sn-glycero phosphocholine (DLPC). Small-angle X-ray scattering (SAXS), small angle neutron scattering (SANS), and optical microscopy of the complexes are consistent with a condensed multilamellar structure with PGA macromolecules sandwiched between the bilayers of the lipids. At the isoelectric point of the complex, lipid dilution experiments at increasing ratios of the neutral lipid to the cationic lipid resulted in an unexpectedly large increase in the interlamellar "d" spacing from 39 Angstrom for the pure DDAB membrane to 60 Angstrom at very high dilutions. Significantly, SAXS data shows that the lamellar complexes remained single phase which indicates that PGA interchain interactions are repulsive with their average spacing increasing with increasing lipid dilution. The data are consistent with a model of a "pinched lamellar" phase of the lipid-PGA complex where the PGA macromolecule and DDAB associate to form localized pinched regions. Between PGA-membrane "pinches" large pockets of water stabilized by hydration repulsion are contained and the system behaves as a nearly pure DLPC membrane with a large equilibrium spacing of 60 Angstrom. These results suggest that biologically active molecules could be incorporated in the large hydration domains between "pinched" regions for delivery applications. C1 Univ Calif Santa Barbara, Dept Mat, Biochem & Mol Biol Program, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Phys, Biochem & Mol Biol Program, Santa Barbara, CA 93106 USA. Univ Calif Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA. RP Subramanian, G (reprint author), Univ Calif Santa Barbara, Dept Mat, Biochem & Mol Biol Program, Santa Barbara, CA 93106 USA. RI Lujan Center, LANL/G-4896-2012; Deming, Timothy/I-5411-2013; OI Deming, Timothy/0000-0002-0594-5025 NR 35 TC 43 Z9 43 U1 0 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 12 PY 2000 VL 122 IS 1 BP 26 EP 34 DI 10.1021/ja991905j PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 275AB UT WOS:000084796300005 ER PT J AU Pfrommer, BG Mauri, F Louie, SG AF Pfrommer, BG Mauri, F Louie, SG TI NMR chemical shifts of ice and liquid water: The effects of condensation SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID DENSITY-FUNCTIONAL THEORY; MOLECULAR-DYNAMICS SIMULATION; SHIELDING CONSTANTS; H2O; PSEUDOPOTENTIALS; DEPENDENCE; SECONDARY; TENSORS; SOLIDS; (H2O)2 AB We report the results of ab Initio density functional theory calculations of the NMR chemical shift of liquid water and hexagonal ice. Depending on the structural model used, the calculated isotropic shift of ice Ih with respect to the gas phase is -8.0 +/- 0.2 or -8.1 +/- 0.1 ppm for the proton, and -48.6 +/- 0.02 or -48.1 +/- 0.02 ppm for oxygen. The proton anisotropy is -33.4 +/- 0.2 or -33.6 +/- 0.2 ppm. Using snapshots from ab initio molecular dynamics simulations, we find a gas-to-liquid shift of -5.8 +/- 0.1 ppm for hydrogen, and -36.6 +/- 0.5 ppm for oxygen. Molecules beyond the first solvation shell influence the proton chemical shift predominantly via the electric field generated by their permanent electric dipole moment. Finally, we show that it is possible to reproduce the proton chemical shifts in the condensed phases by an empirical function of the local molecular geometry. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Paris 06, Lab Mineral Cristallog, F-75252 Paris, France. Univ Paris 07, CNRS, F-75252 Paris, France. RP Louie, SG (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI mauri, francesco/K-5726-2012 OI mauri, francesco/0000-0002-6666-4710 NR 50 TC 94 Z9 94 U1 1 U2 20 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD JAN 12 PY 2000 VL 122 IS 1 BP 123 EP 129 DI 10.1021/ja991961k PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 275AB UT WOS:000084796300017 ER PT J AU Robinson, BA Viswanathan, HS Valocchi, AJ AF Robinson, BA Viswanathan, HS Valocchi, AJ TI Efficient numerical techniques for modeling multicomponent ground-water transport based upon simultaneous solution of strongly coupled subsets of chemical components SO ADVANCES IN WATER RESOURCES LA English DT Article ID REACTIVE TRANSPORT; POROUS-MEDIA; SYSTEMS; FLOW; FORMULATION; AQUIFERS; KINETICS AB An iterative solution technique for reactive transport problems is developed, which we call the selective coupling method, that represents a versatile alternative to traditional uncoupled iterative techniques and the fully coupled global implicit method. The chemical formulation studied allows a combination of equilibrium and kinetic reactions, and therefore is a more versatile model formulation than a purely equilibrium-based system. However, this is a very challenging system for obtaining an efficient numerical solution. Techniques that sequentially compute the concentrations of aqueous components possibly ignore important derivatives in the Jacobian matrix of the full system of equations. The selective coupling method developed here allows only the strongly coupled components to be solved together, and the transport iteration consists of solving groups of components simultaneously. We also develop a method denoted as coupled normalization to reduce the computational work and memory requirements for particular types of reactive transport problems. These approaches can result in computational savings relative to the global implicit method by achieving a similar iteration count while reducing the cpu time per iteration. More importantly, the memory requirements of the selective coupling technique are controlled by the maximum number of coupled components, rather than by the total number of components. For complex aqueous chemical systems and grids with a large number of nodes, memory efficiency is the characteristic that makes the selective coupling method particularly attractive relative to the global implicit method. A series of example cases illustrate the efficiency of the new approach. These test problems are also used to address the implementation issues surrounding the most efficient strategy for coupling the aqueous components when carrying out the chemical transport iteration. In-depth knowledge of the behavior of the chemical system is required to select an appropriate solution strategy. Published by Elsevier Science Ltd. C1 Univ Calif Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. Univ Illinois, Dept Civil & Environm Engn, Urbana, IL 61801 USA. RP Robinson, BA (reprint author), Univ Calif Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. RI Robinson, Bruce/F-6031-2010 NR 31 TC 34 Z9 34 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0309-1708 J9 ADV WATER RESOUR JI Adv. Water Resour. PD JAN 11 PY 2000 VL 23 IS 4 BP 307 EP 324 DI 10.1016/S0309-1708(99)00034-2 PG 18 WC Water Resources SC Water Resources GA 272ZV UT WOS:000084682100001 ER PT J AU Jacobs, JM Coulter, RL Brutsaert, W AF Jacobs, JM Coulter, RL Brutsaert, W TI Surface heat flux estimation with wind-profiler/RASS and radiosonde observations SO ADVANCES IN WATER RESOURCES LA English DT Article ID BOUNDARY-LAYER; SHEAR-STRESS; TEMPERATURE; RASS; VEGETATION; ROUGHNESS AB A bulk ABL similarity approach was used to make regional estimates of the sensible heat flux by combining surface temperature measurements with mixed layer temperature and wind speed profiles. The mixed layer profiles were measured by a 915 MHz Profiler/Radio Acoustic Sounding System and by radiosondes in north-central Oklahoma at the ARM Southern Great Plains CART Central Facility. A comparison of calculated sensible heat flux values with regional mean values measured at two ground stations showed good agreement with r = 0.88 and r = 0.76 for the 915 MHz profiler and the radiosonde data sets, respectively. Estimates of friction velocity u, by means of radiosonde wind profiles gave good results when compared to values measured by an surface eddy correlation system with a correlation coefficient r = 0.77. However, u, values obtained from wind profiles measured by the 915 MHz profiler were underestimated, because these velocity measurements were systematically too small. The results also show that the 915 MHz Profiler/Radio Acoustic Sounding System is capable of providing the needed temperature measurements to make reasonable regional estimates of sensible heat fur. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Florida, Dept Civil Engn, Gainesville, FL 32611 USA. Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. Cornell Univ, Sch Civil & Environm Engn, Ithaca, NY 14853 USA. RP Jacobs, JM (reprint author), Univ Florida, Dept Civil Engn, Gainesville, FL 32611 USA. NR 21 TC 4 Z9 4 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0309-1708 J9 ADV WATER RESOUR JI Adv. Water Resour. PD JAN 11 PY 2000 VL 23 IS 4 BP 339 EP 348 DI 10.1016/S0309-1708(99)00028-7 PG 10 WC Water Resources SC Water Resources GA 272ZV UT WOS:000084682100003 ER PT J AU Stanescu, M Samha, H Perlstein, J Whitten, DG AF Stanescu, M Samha, H Perlstein, J Whitten, DG TI Unusual folded structures for a tethered squaraine-cholesterol derivative in Langmuir-Blodgett films SO LANGMUIR LA English DT Article ID MOLECULAR SELF-ASSEMBLIES; SQUARYLIUM DYE; AGGREGATION; ORIENTATION; ABSORPTION; SPECTRA; LAYERS; GELS AB A squaraine-cholesterol diad, 1, which has been found to be a good gelator, has been studied in films at the air-water inter face and in supported Langmuir-Blodgett films. Both experimental observations and simulations are consistent with a low-energy folded structure in which there are attractive noncovalent interactions between the squaraine chromophore and the steroid. Although different structures seem Likely for 1 in both the crystal and organogels, the present studies suggest that the folded structure exists in both uncompressed and compressed films at the air-water interface and in supported LB films. In both environments the squaraine chromophore shows evidence of squaraine-squaraine aggregation; both "J" and "H" aggregates are indicated depending upon the conditions imposed upon the film. C1 Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Univ Rochester, Dept Chem, Ctr Photoinduced Charge Transfer, Rochester, NY 14627 USA. RP Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. NR 25 TC 12 Z9 12 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JAN 11 PY 2000 VL 16 IS 1 BP 275 EP 281 DI 10.1021/la990755n PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 273GE UT WOS:000084698900042 ER PT J AU Castoldi, A Rehak, P Gatti, E Guazzoni, C De Geronimo, G AF Castoldi, A Rehak, P Gatti, E Guazzoni, C De Geronimo, G TI Modified Poisson solver for the simulation of the silicon-oxide interface in semiconductor detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY DE Poisson solver; semiconductor detectors; silicon-oxide interface AB We present a modified Poisson solver for depleted semiconductor detectors that takes into account the effects of possible accumulation of mobile charge at the silicon-oxide interfaces. The solver is based on a physical model that closely approximates the correct boundary condition at the silicon-oxide interface. The model assumes that the silicon-oxide interface is divided into an equipotential region, where the electron layer is located, and a fully depleted region. The actual extension and potential of the electron layer region are approximated with the desired accuracy by an iterative procedure. This model has been implemented in 2- and 3-D Poisson solvers. The comparison with a 2-D drift-diffusion simulator has shown the accuracy of the proposed method. The modified Poisson solver has shown to be useful in giving accurate solutions to 3-D design problems at high CPU speed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Politecn Milan, Dipartimento Ingn Nucl Ce SNEF, I-20133 Milan, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. Politecn Milan, Dipartimento Elettr & Informat, I-20133 Milan, Italy. RP Castoldi, A (reprint author), Politecn Milan, Dipartimento Ingn Nucl Ce SNEF, P Za Leonardo Vinci 32, I-20133 Milan, Italy. RI Guazzoni, Chiara/A-5070-2008 OI Guazzoni, Chiara/0000-0001-6399-8670 NR 6 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2000 VL 439 IS 2-3 BP 275 EP 281 DI 10.1016/S0168-9002(99)00902-X PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100011 ER PT J AU Manfredi, PF Leona, A Mandelli, E Perazzo, A Re, V AF Manfredi, PF Leona, A Mandelli, E Perazzo, A Re, V TI Noise limits in a front-end system based on time-over-threshold signal processing SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY DE front-end system; time-over-threshold; signal; noise ID SILICON VERTEX TRACKER AB An analog signal processor based on the Time-over-Threshold (ToT) range compression is employed in the front-end section of the readout chip of the microstrip vertex detector for the BaBar experiment. The paper, after describing the circuit solutions that have been adopted to optimize the ToT operation, focuses on the noise aspects of the ToT processor. Comparisons are made between the signal-to-noise ratio in the linear processor preceding the ToT circuit and that obtained at the output of the entire analog channel including the ToT function. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Bergamo, Dipartimento Ingn, I-24044 Dalmine, BG, Italy. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Ist Nazl Fis Nucl, Sezione Pavia, I-27100 Pavia, Italy. Univ Pavia, Dipartimento Elettr, I-27100 Pavia, Italy. RP Re, V (reprint author), Univ Bergamo, Dipartimento Ingn, Viale Marconi 5, I-24044 Dalmine, BG, Italy. OI Re, Valerio/0000-0003-0697-3420 NR 7 TC 23 Z9 24 U1 1 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 JAN 11 PY 2000 VL 439 IS 2-3 BP 361 EP 367 DI 10.1016/S0168-9002(99)00852-9 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100020 ER PT J AU Fazzi, A Rehak, P AF Fazzi, A Rehak, P TI Performance of an X-ray spectroscopic system based on a double-gate double-feedback charge preamplifier SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY DE low noise charge preamplifier; double-gate double-feedback; base line fluctuations ID SILICON DRIFT DETECTOR; LOW-NOISE; JFET AB The performance of a near room temperature X-ray spectroscopic system is reported. The system is based on a charge preamplifier with the first transistor having two separated gates. The preamplifier operates in a continuous reset mode without any physical resistor connected to the input node. The leakage current and the current due to the rate of X-rays is neutralized by an average current of holes, flowing under the control of an additional feedback, from the bottom to the top gate. The preamplifier is followed by a simple circuit which exactly cancels the long tail of the impulse response of a pure double-gate preamplifier. The compensation of this tail, due to the very principle of the preamplifier's continuous reset through the double-gate mechanism, improves substantially the high-rate performance of the system. The preamplifier based on a commercially available double-gate front JFET MX-40 (MOXTEK) coupled to a silicon drift detector produced at BNL achieved ENC of 13 electrons at -30 degrees C. The analysis of the system's performance, the noise analysis and optimization are described. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Politecn Milan, Dipartimento Ingn Nucl, I-20133 Milan, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Fazzi, A (reprint author), Politecn Milan, Dipartimento Ingn Nucl, Via Ponzio 34-3, I-20133 Milan, Italy. NR 8 TC 5 Z9 5 U1 2 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 JAN 11 PY 2000 VL 439 IS 2-3 BP 391 EP 402 DI 10.1016/S0168-9002(99)00905-5 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100025 ER PT J AU Yarema, RJ Zimmerman, T Srage, J Antonuk, LE Berry, J Huang, W Maolinbay, M AF Yarema, RJ Zimmerman, T Srage, J Antonuk, LE Berry, J Huang, W Maolinbay, M TI A programmable, low noise, multichannel ASIC for readout of pixelated amorphous silicon arrays SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY ID MEGAVOLTAGE AB Pixelated amorphous silicon arrays used for detecting X-rays have a number of special requirements for the readout electronics. Because the pixel detector is a high-density array, custom integrated circuits are very desirable for reading out the column signals and addressing the rows of pixels to be read out. In practice. separate chips are used for readout and addressing. This payer discusses a custom integrated circuit for processing the analog column signals. The chip has 32 channels of low-noise integrators followed by sample and hold circuits which perform a correlated double sample. The chip has several programmable features including gain, bandwidth, and readout configuration. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Michigan, Med Ctr, Dept Radiat Oncol, Ann Arbor, MI 48109 USA. RP Yarema, RJ (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 3 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 JAN 11 PY 2000 VL 439 IS 2-3 BP 413 EP 417 DI 10.1016/S0168-9002(99)00900-6 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100027 ER PT J AU Lynn, D Bellwied, R Beuttenmueller, R Caines, H Chen, W DiMassimo, D Dyke, H Elliott, D Grau, M Hoffmann, GW Humanic, T Jensen, P Kleinfelder, SA Kotov, I Kraner, HW Kuczewski, P Leonhardt, B Li, Z Liaw, CJ LoCurto, G Middelkamp, P Minor, R Mazeh, N Nehmeh, S O'Conner, P Ott, G Pandey, SU Pruneau, C Pinelli, D Radeka, V Rescia, S Rykov, V Schambach, J Sedlmeir, J Sheen, J Soja, B Stephani, D Sugarbaker, E Takahashi, J Wilson, K AF Lynn, D Bellwied, R Beuttenmueller, R Caines, H Chen, W DiMassimo, D Dyke, H Elliott, D Grau, M Hoffmann, GW Humanic, T Jensen, P Kleinfelder, SA Kotov, I Kraner, HW Kuczewski, P Leonhardt, B Li, Z Liaw, CJ LoCurto, G Middelkamp, P Minor, R Mazeh, N Nehmeh, S O'Conner, P Ott, G Pandey, SU Pruneau, C Pinelli, D Radeka, V Rescia, S Rykov, V Schambach, J Sedlmeir, J Sheen, J Soja, B Stephani, D Sugarbaker, E Takahashi, J Wilson, K TI A 240-channel thick film multi-chip module for readout of silicon drift detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY AB We have developed a thick film multi-chip module for readout of silicon drift (or low capacitance similar to 200 fF) detectors. Main elements of the module include a custom 16-channel NPN-BJT preamplifier-shaper (PASA) and a custom 16-channel CMOS Switched Capacitor Array (SCA). The primary design criteria of the module were the minimizations of the power (12 mW/channel), noise (ENC = 490 e(-) rms), size (20.5 mm x 63 mm), and radiation length (1.4%). We will discuss various aspects of the PASA design, with emphasis on the preamplifier feedback network. The SCA is a modification of an integrated circuit that has been previously described [1]; its design features specific to its application in the SVT (Silicon Vertex Tracker in the STAR experiment at RHIC) will be discussed. The 240-channel multi-chip module is a circuit with five metal layers fabricated in thick film technology on a beryllia substrate and contains 35 custom and commercial integrated circuits. It has been recently integrated with silicon drift detectors in both a prototype system assembly for the SVT and a silicon drift array for the E896 experiment at the Alternating Gradient Synchrotron at the Brookhaven National Laboratory. We will discuss features of the module's design and fabrication, report the test results, and emphasize its performance both on the bench and under experimental conditions. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Wayne State Univ, Detroit, MI 48202 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Texas, Austin, TX 78712 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Sao Paulo, BR-05508 Sao Paulo, Brazil. RP Lynn, D (reprint author), Brookhaven Natl Lab, POB 5000,Bldg 510A, Upton, NY 11973 USA. RI Rescia, Sergio/D-8604-2011; Takahashi, Jun/B-2946-2012 OI Rescia, Sergio/0000-0003-2411-8903; Takahashi, Jun/0000-0002-4091-1779 NR 4 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2000 VL 439 IS 2-3 BP 418 EP 426 DI 10.1016/S0168-9002(99)00934-1 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100028 ER PT J AU Castoldi, A Chen, W Gatti, E Holl, P Rehak, P AF Castoldi, A Chen, W Gatti, E Holl, P Rehak, P TI Fast silicon drift photodiodes free from bias connections on the light entering side SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY ID TEMPERATURE-DEPENDENCE; RAY SPECTROSCOPY; DETECTORS; CHAMBER AB A new type of silicon drift photodiode intended to be coupled to large area scintillators is described. The diodes have a relatively large area (1 cm(2)) and a short maximal drift time (300 ns). They operate without requiring any external electrical connection at the side of the photodiode coupled to the scintillating crystal. These new photodiodes have almost identical ring structures on both sides with individual rings being at linearly increasing potentials providing the required high electric drift field. A new feature of the presented photodiodes is a small modification of the electrode structure near the signal collecting anode. It allows a full depletion of the photodiode and the highest drift field. Advantages and drawbacks of this kind of photodiodes are described. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Politecn Milan, I-20133 Milan, Italy. MPI Halbleiterlab, D-81245 Munich, Germany. RP Rehak, P (reprint author), Brookhaven Natl Lab, Bld 510C, Upton, NY 11973 USA. NR 12 TC 4 Z9 4 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2000 VL 439 IS 2-3 BP 483 EP 496 DI 10.1016/S0168-9002(99)00935-3 PG 14 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100035 ER PT J AU Takahashi, J Bellwied, R Beuttenmuller, R Caines, H Chen, W DiMassimo, D Dyke, H Elliot, D Grau, M Hoffmann, GW Humanic, T Jensen, P Kotov, IV Kraner, HW Kuczewski, P Leonhardt, W Li, Z Liaw, C LoCurto, G Lynn, D Mazeh, N Middelkamp, P Minor, R Nehmeh, S Ott, G Pandey, SU Pinelli, D Pruneau, C Rykov, VL Schambach, J Sedlmeir, J Sheen, J Soja, R Stefani, D Sugarbaker, E Wilson, WK AF Takahashi, J Bellwied, R Beuttenmuller, R Caines, H Chen, W DiMassimo, D Dyke, H Elliot, D Grau, M Hoffmann, GW Humanic, T Jensen, P Kotov, IV Kraner, HW Kuczewski, P Leonhardt, W Li, Z Liaw, C LoCurto, G Lynn, D Mazeh, N Middelkamp, P Minor, R Nehmeh, S Ott, G Pandey, SU Pinelli, D Pruneau, C Rykov, VL Schambach, J Sedlmeir, J Sheen, J Soja, R Stefani, D Sugarbaker, E Wilson, WK CA STAR-SVT Collaboration TI Silicon drift detectors for the STAR/SVT experiment at RHIC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY ID CHAMBERS AB Large-area linear Silicon Drift Detectors (SDD) were developed to be used in the Silicon Vertex Tracker (SVT) of the STAR experiment at the BNL Relativistic Heavy ton Collider (RHIC). The design of the SDD has been finalized and submitted for large-scale production. Test results show that the detector exhibits excellent position resolution and low noise. A special characterization procedure was developed to test detector wafers in order to select good detectors for the SVT. Recently, 15 STAR/SVT SDDs were assembled as a tracking device in a BNL-AGS heavy-ion experiment (E896). This was the first tracking application of these detectors and their corresponding front-end electronics in an experimental environment. Preliminary results indicating good detector performance are shown and discussed in this paper. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. Wayne State Univ, Detroit, MI 48201 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Texas, Austin, TX 78712 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Sao Paulo, Sao Paulo, Brazil. RP Takahashi, J (reprint author), Brookhaven Natl Lab, Instrumentat Div, Bldg 535B,POB 500, Upton, NY 11973 USA. RI Takahashi, Jun/B-2946-2012 OI Takahashi, Jun/0000-0002-4091-1779 NR 13 TC 15 Z9 15 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2000 VL 439 IS 2-3 BP 497 EP 506 DI 10.1016/S0168-9002(99)00918-3 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100036 ER PT J AU Bellwied, R Beuttenmuller, R Brandon, N Caines, H Chen, W DiMassimo, D Dyke, H Hall, JR Hardtke, D Hoffmann, GW Humanic, TJ Kotova, AI Kotov, IV Kraner, HW Li, Z Lynn, D Middelkamp, P Ott, G Pandey, SU Pruneau, C Rykov, VL Schambach, J Sedlmeir, J Sugarbaker, E Takahashi, J Wilson, WK AF Bellwied, R Beuttenmuller, R Brandon, N Caines, H Chen, W DiMassimo, D Dyke, H Hall, JR Hardtke, D Hoffmann, GW Humanic, TJ Kotova, AI Kotov, IV Kraner, HW Li, Z Lynn, D Middelkamp, P Ott, G Pandey, SU Pruneau, C Rykov, VL Schambach, J Sedlmeir, J Sugarbaker, E Takahashi, J Wilson, WK CA STAR-SVT Collaboration TI Studies of dynamics of electron clouds in STAR silicon drift detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY DE drift detectors; ionizing particles AB The dynamics of electrons generated in silicon drift detectors was studied using an IR LED. Electrons were generated at different drift distances. In this way, the evolution of the cloud as a function of drift time was measured. Two methods were used to measure the cloud size. The method of cumulative functions was used to extract the electron cloud profiles. Another method obtains the cloud width from measurements of the charge collected on a single anode as a function of coordinate of the light spot. The evolution of the electron cloud width with drift time is compared with theoretical calculations. Experimental results agreed with theoretical expectations. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Ohio State Univ, Dept Phys, Van de Graaft Accelerator Lab, Columbus, OH 43210 USA. Wayne State Univ, Detroit, MI 48201 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Texas, Austin, TX 78712 USA. IHEP, RU-148284 Protvino, Moscow Region, Russia. Univ Sao Paulo, Sao Paulo, Brazil. RP Kotov, IV (reprint author), Ohio State Univ, Dept Phys, Van de Graaft Accelerator Lab, 1302 Kinnear Rd, Columbus, OH 43210 USA. RI Takahashi, Jun/B-2946-2012 OI Takahashi, Jun/0000-0002-4091-1779 NR 9 TC 8 Z9 8 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2000 VL 439 IS 2-3 BP 507 EP 512 DI 10.1016/S0168-9002(99)00930-4 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100037 ER PT J AU Castoldi, A Gatti, E Guazzoni, C Longoni, A Rehak, P Struder, L AF Castoldi, A Gatti, E Guazzoni, C Longoni, A Rehak, P Struder, L TI The controlled-drift detector SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY DE X-ray imaging; fast read-out; X-ray detectors ID SILICON; ENERGY AB A new position-sensing X-ray detector is presented, The novel device is called Controlled-Drift Detector (CDD). The detector is fully depleted and is operated by switching between integration and drift modes, The relevant details of the detector design are discussed. A complete experimental characterization of the fast readout of the integrated signal charges achievable with static drift fields in the range 100-400 V/cm has been carried out. Preliminary measurements to evaluate the charge-handling capacity are also shown. The CDD can provide unambiguous two-dimensional position measurement, high-resolution X-ray spectroscopy and time resolution below 1 ms. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Politecn Milan, I-20133 Milan, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. MPI Halbleiterlab, D-81739 Munich, Germany. RP Castoldi, A (reprint author), Politecn Milan, Pza L da Vinci 32, I-20133 Milan, Italy. RI Guazzoni, Chiara/A-5070-2008 OI Guazzoni, Chiara/0000-0001-6399-8670 NR 10 TC 22 Z9 22 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 JAN 11 PY 2000 VL 439 IS 2-3 BP 519 EP 528 DI 10.1016/S0168-9002(99)00903-1 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100039 ER PT J AU Luke, PN Amman, M Lee, JS Yaver, H AF Luke, PN Amman, M Lee, JS Yaver, H TI Coplanar-grid CdZnTe detector with three-dimensional position sensitivity SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY DE CdZnTe detector; position sensitive; gamma-ray detector ID GAMMA-RAY DETECTORS; RESOLUTION AB A three-dimensional position-sensitive coplanar-grid detector design for use with compound semiconductors is described. This detector design maintains the advantage of a coplanar-grid detector in which good energy resolution can be obtained from materials with poor charge transport. Position readout in two dimensions is accomplished using proximity-sensing electrodes adjacent to the electron-collecting grid electrode of the detector. Additionally, depth information is obtained by taking the ratio of the amplitudes of the collecting grid signal and the cathode signal. Experimental results from a prototype CdZnTe detector are presented. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Luke, PN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS 70A-3363,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 8 TC 13 Z9 14 U1 0 U2 5 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 JAN 11 PY 2000 VL 439 IS 2-3 BP 611 EP 618 DI 10.1016/S0168-9002(99)00873-6 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100050 ER PT J AU Verbitskaya, E Eremin, V Ivanov, A Strokan, N Vasilev, V Markov, A Polyakov, A Gavrin, V Kozlova, Y Veretenkin, E Bowles, TJ AF Verbitskaya, E Eremin, V Ivanov, A Strokan, N Vasilev, V Markov, A Polyakov, A Gavrin, V Kozlova, Y Veretenkin, E Bowles, TJ TI Charge collection efficiency in SIGaAs grown from melts with variable composition as a material for solar neutrino detection SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY DE solar neutrino detectors; stoichiometry ID GAAS AB The results on electrical characteristics and charge collection efficiency in the detectors from hulk SI GaAs developed as a material For solar neutrino spectroscopy are presented. SI GaAs crystals were grown by the Czochralski method. The changes in the stoichiometric components are permanently controlled. It is shown that the performance of GaAs p(+)-i-n(+) structures provided the range of operational reverse voltage up to 1 kV. Measurement of deep level spectra and their analysis reveal the dominant deep levels - hole traps E-v + 0.51 and + 0.075 eV in GaAs grown from stoichiometric and nonstoichiometric melts, respectively. Investigation of carrier transport properties and hulk homogeneity evinced in charge collection efficiency has shown advantageous results for SI GaAs grown from stoichiometric melt. The reduction of carrier transport parameters and charge collection efficiency in GaAs grown from nonstoichiometric melt is analyzed taking into consideration formation of the hole trap E-v + 0.075 eV, presumably assigned to Ga antisite and its influence on the concentration of the ionized deep donor level EL2(+). (C) 2000 Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. Inst Chem Problems Microelect, Moscow, Russia. Russian Acad Sci, Nucl Res Inst, Moscow, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Verbitskaya, E (reprint author), Russian Acad Sci, AF Ioffe Physicotech Inst, 26 Politechnicheskaya Str, St Petersburg 194021, Russia. RI Verbitskaya, Elena/D-1521-2014; Ivanov, Alexander/E-3993-2014; Vasiliev, Vladislav/C-3982-2015 NR 12 TC 7 Z9 7 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 JAN 11 PY 2000 VL 439 IS 2-3 BP 634 EP 646 DI 10.1016/S0168-9002(99)00853-0 PG 13 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100053 ER PT J AU Markov, AV Polyakov, AY Smirnov, NB Govorkov, AV Eremin, VK Verbitskaya, EM Gavrin, VN Kozlova, YP Veretenkin, YP Bowles, TJ AF Markov, AV Polyakov, AY Smirnov, NB Govorkov, AV Eremin, VK Verbitskaya, EM Gavrin, VN Kozlova, YP Veretenkin, YP Bowles, TJ TI Study of GaAs as a material for solar neutrino detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th European Symposium on Semiconductor Detectors CY JUN 14-17, 1998 CL SCHLOSS ELMAU, GERMANY DE gallium arsenide; particle detector; deep levels ID RADIATION DETECTORS; SEMIINSULATING GAAS; PARTICLE DETECTORS; FIELD AB Semi-insulating GaAs crystals grown by liquid encapsulated Czochralski technique from Ga-rich melts were evaluated as a possible material for radiation detectors with a high active layer thickness. The density of deep traps, particularly the midgap EL2 donors pinning the Fermi level, was measured by various techniques in conducting and semi-insulating samples. For EL2 traps, a direct evidence of their partial neutralization in the space charge region of reverse biased Schottky diodes due to nonequilibrium capture of electrons is presented for the first time. It is shown that the density of EL2 centers decreases with decreased As composition of the melt very gradually, especially for post-growth annealed samples. Subsequently, if one aims to decrease the EL2 density to such an extent that it would make a serious impact on the depletion layer width in GaAs-based detectors one has to grow semi-insulating GaAs crystals from melts with As composition below about 43% which poses a problem for the preservation of high resistivity of the material due to the relatively high concentration of compensating accepters. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Inst Chem Problems Microelect, Moscow 109017, Russia. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 196140, Russia. Russian Acad Sci, Inst Nucl Res, Moscow, Russia. Univ Calif Los Alamos Natl Lab, Los Angeles, CA USA. RP Polyakov, AY (reprint author), Inst Chem Problems Microelect, B Tomachevsky 5, Moscow 109017, Russia. RI Verbitskaya, Elena/D-1521-2014; Smirnov, Nickolai/K-8935-2015 OI Smirnov, Nickolai/0000-0002-4993-0175 NR 23 TC 16 Z9 17 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JAN 11 PY 2000 VL 439 IS 2-3 BP 651 EP 661 DI 10.1016/S0168-9002(99)00849-9 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 272MK UT WOS:000084654100055 ER PT J AU Puretzky, AA Geohegan, DB Fan, X Pennycook, SJ AF Puretzky, AA Geohegan, DB Fan, X Pennycook, SJ TI In situ imaging and spectroscopy of single-wall carbon nanotube synthesis by laser vaporization SO APPLIED PHYSICS LETTERS LA English DT Article ID ABLATION PLUME; LARGE-SCALE; KRF-LASER; GAS; PYROLYSIS AB The synthesis of single-wall carbon nanotubes by Nd:YAG laser vaporization of a graphite/(Ni, Co) target is investigated by laser-induced luminescence imaging and spectroscopy of Co atoms, C-2 and C-3 molecules, and clusters at 1000 degrees C in flowing 500 Torr Ar. These laser-induced emission images under typical synthesis conditions show that the plume of vaporized material is segregated and confined within a vortex ring which maintains a similar to 1 cm(3) volume for several seconds. Using time-resolved spectroscopy and spectroscopic imaging, the time for conversion of atomic and molecular species to clusters was measured for both carbon (200 mu s) and cobalt (2 ms). This rapid conversion of carbon to nanoparticles, combined with transmission electron microscopy analysis of the collected deposits, indicate that nanotube growth occurs over several seconds in a plume of mixed nanoparticles. By adjusting the time spent by the plume within the high-temperature zone using these in situ diagnostics, single-walled nanotubes of controlled length were grown at an estimated rate of 0.2 mu m/s. (C) 2000 American Institute of Physics. [S0003-6951(00)02102-1]. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Puretzky, AA (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Puretzky, Alexander/B-5567-2016; Geohegan, David/D-3599-2013 OI Puretzky, Alexander/0000-0002-9996-4429; Geohegan, David/0000-0003-0273-3139 NR 18 TC 99 Z9 102 U1 0 U2 13 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 10 PY 2000 VL 76 IS 2 BP 182 EP 184 DI 10.1063/1.125696 PG 3 WC Physics, Applied SC Physics GA 270NA UT WOS:000084541000018 ER PT J AU Mair, RA Lin, JY Jiang, HX Jones, ED Allerman, AA Kurtz, SR AF Mair, RA Lin, JY Jiang, HX Jones, ED Allerman, AA Kurtz, SR TI Time-resolved photoluminescence studies of InxGa1-xAs1-yNy SO APPLIED PHYSICS LETTERS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; MULTIPLE-QUANTUM WELLS; LASER-DIODES; EMISSION; OPERATION; SHIFT; GAAS AB Time-resolved photoluminescence spectroscopy has been used to investigate carrier decay dynamics in a InxGa1-xAs1-yNy (x similar to 0.03, y similar to 0.01) epilayer grown on GaAs by metal organic chemical vapor deposition. Time-resolved photoluminescence (PL) measurements, performed for various excitation intensities and sample temperatures, indicate that the broad PL emission at low temperature is dominated by localized exciton recombination. Lifetimes in the range of 0.07-0.34 ns are measured; these photoluminescence lifetimes are significantly shorter than corresponding values obtained for GaAs. In particular, we observe an emission energy dependence of the decay lifetime at 10 K, whereby the lifetime decreases with increasing emission energy across the PL spectrum. This behavior is characteristic of a distribution of localized states, which arises from alloy fluctuations. (C) 2000 American Institute of Physics. [S0003-6951(00)03702-5]. C1 Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Mair, RA (reprint author), Kansas State Univ, Dept Phys, Cardwell Hall, Manhattan, KS 66506 USA. RI Lin, Jingyu/A-7276-2011; Jiang, Hongxing/F-3635-2011 OI Lin, Jingyu/0000-0003-1705-2635; Jiang, Hongxing/0000-0001-9892-4292 NR 20 TC 144 Z9 148 U1 0 U2 17 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 10 PY 2000 VL 76 IS 2 BP 188 EP 190 DI 10.1063/1.125698 PG 3 WC Physics, Applied SC Physics GA 270NA UT WOS:000084541000020 ER PT J AU Wei, YY Eres, G AF Wei, YY Eres, G TI Self-limiting behavior of scanning-electron-beam-induced local oxidation of hydrogen-passivated silicon surfaces SO APPLIED PHYSICS LETTERS LA English DT Article ID FIELD-INDUCED OXIDATION; FORCE MICROSCOPE; PROBE OXIDATION; DONOR STATES; GENERATION; INTERFACE; KINETICS; LITHOGRAPHY; CHARGE; AIR AB The mechanism and the kinetics of electron-beam-induced local oxidation of an H-passivated Si surface in the electron energy range from 10 to 40 keV was investigated using scanning-electron-beam lithography. The volume expansion of Si upon oxidation produces a negative image surface pattern that can be imaged by atomic force microscopy. This latent pattern was used to study the dependence of the height and width of dot and line patterns as a function of the electron-beam exposure parameters. Patterns with minimum linewidth below 50 nm have been obtained. Similarly to atomic-force-microscope-induced local oxidation of Si, the height and linewidth saturate with electron dose for a given accelerating voltage. The saturation height roughly scales with the accelerating voltage, and depends more strongly on the accelerating voltage than the linewidth. The experimental results are interpreted by a mechanism that is based on charge generation and transport through the evolving insulating SiO2 layer. (C) 2000 American Institute of Physics. [S0003-6951(00)01202-X]. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Wei, YY (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Eres, Gyula/C-4656-2017 OI Eres, Gyula/0000-0003-2690-5214 NR 19 TC 11 Z9 11 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 10 PY 2000 VL 76 IS 2 BP 194 EP 196 DI 10.1063/1.125700 PG 3 WC Physics, Applied SC Physics GA 270NA UT WOS:000084541000022 ER PT J AU Papadopoulos, PP Rottgering, HJA van der Werf, PP Guilloteau, S Omont, A van Breugel, WJM Tilanus, RPJ AF Papadopoulos, PP Rottgering, HJA van der Werf, PP Guilloteau, S Omont, A van Breugel, WJM Tilanus, RPJ TI CO (4-3) and dust emission in two powerful high-z radio galaxies, and CO lines at high redshifts SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : formation; galaxies : individual (4C 60.07; 6C 1909+722); galaxies : ISM ID LUMINOUS INFRARED GALAXIES; MOLECULAR GAS; PHYSICAL CONDITIONS; IRAS GALAXIES; CARBON-MONOXIDE; BRIGHT GALAXIES; STAR FORMATION; MASS; Z-SIMILAR-TO-1; CLUSTER AB We report the detection of submillimeter emission from dust at 850 mu m and of the (12)CO J = 4-3 line in the two distant powerful radio galaxies 4C 60.07 (z = 3.79) and 6C 1909 + 722 (z = 3.53). Tn 4C 60.07, the dust emission is also detected at 1.25 mm. The estimated molecular gas masses are large, of the order of similar to(0.5-1)x 10(11) M. The large far-infrared (FIR) luminosities (L(FIR) similar to 10(13) L.) suggest that we are witnessing two major starburst phenomena, while the observed large velocity widths (Delta V(FWHM) greater than or similar to 500 km s(-1)) are characteristic of mergers. In the case of 4C 60.07, the CO emission extends over similar to 30 kpc and spans a velocity range of greater than or similar to 1000 lim s(-1). It consists of two distinct features with FWHM of greater than or similar to 550 km s(-1) and similar to 150 km s(-1), and line centers separated by greater than or similar to 700 km s(-1). The least massive of these components is probably very gas rich, with potentially greater than or similar to 60% of its dynamical mass in the form of molecular gas. The extraordinary morphology of the CO emission in this object suggests that it is not just a scaled-up version of a local ultraluminous infrared galaxy, and it may be a formative stage of the elliptical host of the residing radio-loud active galactic nucleus (AGN). Finally, we briefly explore the effects of the wide range of gas-excitation conditions expected for starburst environments on the luminosity of high-J CO lines and conclude that in unlensed objects, CO (J + 1 --> J), J + 1 > 3 lines can be significantly weak with respect to CO J = 1-0, and this can hinder their detection even in the presence of substantial molecular gas masses. C1 Sterrewacht Leiden, NL-2300 RA Leiden, Netherlands. Inst Radio Astron Millimetr, F-38406 St Martin Dheres, France. CNRS, Inst Astrophys Paris, F-75014 Paris, France. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Joint Astron Ctr, Hilo, HI 96720 USA. RP Papadopoulos, PP (reprint author), Sterrewacht Leiden, Pob 9513, NL-2300 RA Leiden, Netherlands. NR 65 TC 116 Z9 116 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2000 VL 528 IS 2 BP 626 EP 636 DI 10.1086/308215 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282GP UT WOS:000085210100007 ER PT J AU Templeton, MR Bradley, PA Guzik, JA AF Templeton, MR Bradley, PA Guzik, JA TI Asteroseismology of the multiply periodic delta Scuti star theta Tucanae SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : binaries : general; stars : individual (theta Tucanae); stars : oscillations; delta Scuti ID STELLAR OSCILLATIONS; EQUATION; OPAL AB We present an asteroseismological analysis of the delta Scuti component of the binary star system theta Tucanae, using the 10 pulsational frequencies obtained photometrically by Paparo et al. and the mode identifications of Sterken. We have tested theoretical models with masses between 1.8 and 2.8 M-circle dot that have solar metal abundances, and we find that based upon mode stability arguments, the photometrically derived mass estimate of 2.1 +/- 0.1 M-circle dot, is probably accurate. The models with the best frequency match to a Tucanae have masses of 1.9-2.1 M-circle dot, luminosities between 20 and 25 L-circle dot, effective temperatures between 7500 and 7685 K, log g values between 3.82 and 3.92, and rotational velocities between 70 and 90 km s(-1). The luminosities of our models are more than a factor of 2 less than the Hipparcos-derived luminosity of 54 L-circle dot, which suggests that the secondary star must be of comparable luminosity. We cannot determine whether tidal distortion is causing nonspherical perturbations in the pulsating component of this system with our current models, but the frequency spacing of observed pulsation modes suggests that rotation has a strong effect on the observed spectrum. Our models are consistent with the observed pulsation spectrum if rotational splitting is taken into account. Recently, De Mey, Daems, & Sterken determined spectroscopically that the a Tucanae system is a spectroscopic binary with an anomalous mass ratio of 0.0896. In their model of this system, the delta Scuti component of the system is probably the beneficiary of mass transfer from the secondary, and the system was likely once an Algol-type system. The secondary is probably a 0.2 M-circle dot, post-red giant branch object at similar to 7000 K (log g similar to 3.0), which has lost most of its mass via mass transfer and winds. This scenario raises the possibility that the interior of the delta Scuti star may be radically different from what single-star evolution models predict, although our results do not show any obvious differences. However, the age and envelope abundances should be different from single-star model predictions. We believe that this object provides an excellent opportunity to study the interiors of post-mass transfer objects using asteroseismology, and we suggest future observational and theoretical work that will help us understand this system. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Templeton, MR (reprint author), Univ Calif Los Alamos Natl Lab, XTA MS B220, Los Alamos, NM 87545 USA. NR 30 TC 15 Z9 15 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2000 VL 528 IS 2 BP 979 EP 988 DI 10.1086/308191 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282GP UT WOS:000085210100035 ER PT J AU Kane, J Arnett, D Remington, BA Glendinning, SG Bazan, G Muller, E Fryxell, BA Teyssier, R AF Kane, J Arnett, D Remington, BA Glendinning, SG Bazan, G Muller, E Fryxell, BA Teyssier, R TI Two-dimensional versus three-dimensional supernova hydrodynamic instability growth SO ASTROPHYSICAL JOURNAL LA English DT Article DE hydrodynamics; instabilities; methods : numerical; supernovae : general ID RAYLEIGH-TAYLOR INSTABILITY; LINE-PROFILES; SN-1987A; 1987A; EVOLUTION; FRONTS; NICKEL AB Numerical simulations using the SN hydrodynamics code PROMETHEUS are carried out to study the difference between growth of two-dimensional versus three-dimensional single-mode perturbations at the He-H and O-He interfaces of SN 1987A. We find that in the rest frame of an unperturbed one-dimensional interface, a three-dimensional single-mode perturbation grows approximate to 30%-35% faster than a two-dimensional single-mode perturbation, when the wavelengths are chosen to give the same linear stage growth in the planar limit. In simulations where we impose single-mode density perturbations in the O layer of the initial model and random velocity perturbations in the postshock fluid near the He-H interface, we find that both axisymmetric O spikes and three-dimensional O spikes penetrate significantly further than two-dimensional O spikes. The difference between two dimensions and three dimensions predicted by our calculations is not enough to account for the difference between observed Co-56 velocities in SN 1987A and the results of previous two-dimensional simulations of SN 1987A, but our results suggest that the real three-dimensional hydrodynamics are noticeably different than the two-dimensional simulations predict. C1 Univ Arizona, Tucson, AZ 85721 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Max Planck Inst Astrophys, D-85740 Garching, Germany. Univ Chicago, ASCI Flash Ctr, Chicago, IL 60637 USA. Ctr Etud Saclay, Serv Astrophys, DAPNIA, DSM,CEA, F-91191 Gif Sur Yvette, France. RP Kane, J (reprint author), Univ Arizona, L-411 LLNL, Tucson, AZ 85721 USA. NR 30 TC 48 Z9 52 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 10 PY 2000 VL 528 IS 2 BP 989 EP 994 DI 10.1086/308220 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 282GP UT WOS:000085210100036 ER PT J AU Bhardwaj, M Day, D Farhat, C Lesoinne, M Pierson, K Rixen, D AF Bhardwaj, M Day, D Farhat, C Lesoinne, M Pierson, K Rixen, D TI Application of the FETI method to ASCI problems - scalability results on 1000 processors and discussion of highly heterogeneous problems SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE ASCI; FETI; scalability; domain decomposition; structural heterogeneities ID DOMAIN DECOMPOSITION; PARALLEL; OPTIMIZATION AB We report on the application of the one-level FETI method to die solution of a class of structural problems associated with the Department of Energy's Accelerated Strategic Computing Initiative (ASCI). We focus on numerical and parallel scalability issues, and discuss the treatment by PETI of severe structural heterogeneities. We also report on preliminary performance results obtained on the ASCI option Red supercomputer configured with as many as 1000 processors, for problems with as many as 5 million degrees of freedom. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 Univ Colorado, Dept Aerosp Engn Sci, Boulder, CO 80309 USA. Univ Colorado, Ctr Aerosp Struct, Boulder, CO 80309 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Farhat, C (reprint author), Univ Colorado, Dept Aerosp Engn, Boulder, CO 80309 USA. NR 32 TC 58 Z9 58 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD JAN 10 PY 2000 VL 47 IS 1-3 BP 513 EP 535 DI 10.1002/(SICI)1097-0207(20000110/30)47:1/3<513::AID-NME782>3.0.CO;2-V PG 25 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 276FG UT WOS:000084864500025 ER PT J AU Thom, AJ Young, VG Akinc, M AF Thom, AJ Young, VG Akinc, M TI Lattice trends in Ti(5)Si(3)Z(x) (Z=B,C,N,O and 0 < x < 1) SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE titanium silicide; Ti(5)Si(3)Z(x); lattice trends; single crystal; X-ray diffraction ID POLAR INTERMETALLIC COMPOUNDS; INTERSTITIAL CHEMISTRY; PHASES; SYSTEM; MN5SI3-TYPE; SILICIDES; ZR5SB3; HOST AB Several Ti(5)Si(3)Z(x) compositions (Z=boron, carbon, nitrogen and oxygen) were synthesized by are-melting. Powder X-ray diffraction indicates the materials maintain the Mn5Si3-type structure of the binary compound Ti5Si3. Calculated cell constants were correlated to ternary composition based on chemical analysis. Nitrogen and oxygen additions to Ti5Si3 promote a cell volume decrease, while boron additions promote a cell volume increase. Carbon additions cause a decrease in the a-cell constant and an increase in the c-cell constant with a concomitant cell volume increase. Room temperature X-ray single crystal structural analysis was performed on one composition for each ternary addition. Each analyzed composition has the P6(3)/mcm space group (No. 193) with the Mn5Si3-type structure. The ternary addition occupies the normally vacant interstitial site at the center of the trigonal antiprisms of titanium (Ti2) atoms (Ti(6)Z polyhedra), located in chains at the corners of the hexagonal unit cell. Bonding between the interstitial atoms and the titanium (Ti2) atoms in the Ti(6)Z polyhedra is indicated by a decrease in the Ti2-Ti2 and Ti2-Z atomic separations. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA. RP Thom, AJ (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 29 TC 29 Z9 29 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 10 PY 2000 VL 296 IS 1-2 BP 59 EP 66 DI 10.1016/S0925-8388(99)00533-2 PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 269TQ UT WOS:000084494000014 ER PT J AU Balema, VP Pecharsky, AO Ellis, TW Pecharsky, VK AF Balema, VP Pecharsky, AO Ellis, TW Pecharsky, VK TI Preparation and electrochemical properties of some (Sc1-xTix)Ni alloys SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE nickel-metal hydride batteries; scandium, titanium and nickel-containing alloys AB A series of (Sc1-xTix)Ni alloys and their hydrides (Sc1-xTix)NiHy, where x=0, 0.1, 0.3, 0.5, and y=2.9, 2.58, 2.23 and 1.55, have been prepared. The ability to store hydrogen gradually decreases with increasing Ti content in line with the reduction of the unit cell volume from 32.16 Angstrom(3) for ScNi to 29.68 Angstrom(3) for (Sc0.5Ti0.5)Ni. The electrochemical discharge capacity, however, varies in a more complex manner with (Sc0.7Ti0.3)Ni composition displaying the highest value of 231 mAh/g. The discharge capacity losses after 10 electrochemical charge-discharge cycles also vary non-linearity between 46% for (Sc0.9Ti0.1)Ni and 5% for (Sc0.5Ti0.5)Ni. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Kulicke & Sofa Ind Inc, Willow Grove, PA 19090 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Pecharsky, VK (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 6 TC 2 Z9 2 U1 1 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 10 PY 2000 VL 296 IS 1-2 BP 67 EP 71 DI 10.1016/S0925-8388(99)00527-7 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 269TQ UT WOS:000084494000015 ER PT J AU Chakoumakos, BC Sales, BC Mandrus, DG Nolas, GS AF Chakoumakos, BC Sales, BC Mandrus, DG Nolas, GS TI Structural disorder and thermal conductivity of the semiconducting clathrate Sr8Ga16Ge30 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE atomic displacement parameters; semiconductor clathrate; neutron diffraction; Sr8Ga16Ge30 ID GE AB The temperature dependence of the atomic displacement parameters for Sr8Ga16Ge30 determined from refinements of neutron powder and single-crystal diffraction data shows that the anomalously large values for one of the two unique Sr atoms persist from 295 to 11 K. Its position is better described by a fractionally occupied four-fold split site, but the rms displacement remains the largest of all of the atoms in the structure. Difference Fourier maps of this Sr site show a residual nuclear density with lobes in the directions of the split-atom positions. The Ga and Ge atoms appear to be fully disordered on the three distinct framework sites. The measured atomic displacement parameters are used to derive estimates of the following thermodynamic related quantities: Debye temperature, 271 K; mean velocity of sound, 2600 m/s; temperature of the Einstein "rattler", 85 K; mean free path of heat-carrying phonons, 5.36 Angstrom; and lattice thermal conductivity, 0.008 W/cm-K. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Marlow Ind Inc, R&D Div, Dallas, TX 75238 USA. RP Chakoumakos, BC (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Mandrus, David/H-3090-2014; Chakoumakos, Bryan/A-5601-2016 OI Chakoumakos, Bryan/0000-0002-7870-6543 NR 17 TC 140 Z9 144 U1 5 U2 34 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JAN 10 PY 2000 VL 296 IS 1-2 BP 80 EP 86 DI 10.1016/S0925-8388(99)00531-9 PG 7 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 269TQ UT WOS:000084494000018 ER PT J AU Farber, DL Williams, Q Ryerson, FJ AF Farber, DL Williams, Q Ryerson, FJ TI Divalent cation diffusion in Mg2SiO4 spinel (ringwoodite), beta phase (wadsleyite), and olivine: Implications for the electrical conductivity of the mantle SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID GRAIN-BOUNDARY DIFFUSION; CONTROLLED OXYGEN FUGACITY; FE-MG INTERDIFFUSION; SAN-CARLOS-OLIVINE; X-RAY-DIFFRACTION; HIGH-PRESSURE; TRANSFORMATION KINETICS; CHEMICAL ENVIRONMENT; DISLOCATION RECOVERY; SINGLE-CRYSTALS AB Mg-Fe and Mg-Ni interdiffusion coefficients have been measured in single-crystal olivine (alpha-(Mg,Ni,Fe)(2)SiO4), polycrystalline beta phase (beta-(Mg,Ni,Fe)(2)SiO4), and silicate spinel (gamma-(Mg,Ni,Fe)(2)SiO4) at 1473 K between 1 and 14 GPa under controlled thermodynamic conditions. In olivine, D-Mg-Ni(alpha) ranges from 10(-17) m(2) s(-1) at 1 GPa to 4 x 10(-18) m(2) s(-1) at 9 GPa, and D-Mg-Fe(alpha) ranges from 3 x 10(-15) m(2) s(-1) at 1 GPa to m(2) 10(-15) m(2) s(-1) at 4 GPa. At 9 GPa the cation diffusion rates in gamma spinel are similar to 3 orders of magnitude higher than those in olivine; between 9 and 14 GPa, D-Mg-Ni(gamma) decreases from 8 x 10(-15) to 9 X 10(-16) m(2) s(-1), and D-Mg-Fe(gamma) decreases from 2 x 10(-13) to 5 X 10(-14) m(2) s(-1) Between 10 and 14 GPa the diffusion coefficients for both Fe and Ni are similar in magnitude and pressure dependence between beta phase and gamma spinel. The activation volumes for Mg-Ni diffusion are 3.2 and 6.7 cm(3) mol(-1) in the alpha and gamma(beta) phases, respectively, and for Mg-Fe diffusion are 5.4 and 6.1 cm(3) mol(-1) in the alpha and gamma(beta) phases, respectively. Our results demonstrate that extreme differences in transport properties are expected to occur across the 400 km discontinuity. A model for electrical conductivity in the upper mantle involving two mechanisms for electrical conduction, with one mechanism being associated with a hydrogen or defect-related conduction process and the other involving a straightforward application of the Nernst-Einstein equation to our cationic diffusion data, reproduces geomagnetic sounding results for the upper mantle and shallow transition zone. This modeling yields an order of magnitude increase in electrical conductivity across the 400 km discontinuity, with little or no change in conductivity occurring near 520km depth. Our modeling suggests that divalent cation diffusion is the dominant mechanism of charge transport between 400 and 670 km depth and that the high-pressure olivine polymorphs dominate the electrical behavior of the deep upper mantle. Comparison between field-based deep-mantle conductivity profiles derived from magnetotelluric studies and extrapolation of our model suggests that a discontinuity in electrical transport properties exists at the base of the transition zone as well. Similarly, given the dramatic differences in chemical diffusion between different polymorphs of olivine, it is possible that other transport property-mediated processes, such as viscous flow, could dramatically change across the 400 and 670 km discontinuities; such changes are less likely to occur at 520 km depth. C1 Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Inst Tecton, Santa Cruz, CA 95064 USA. RP Farber, DL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. EM farber2@llnl.gov RI Farber, Daniel/F-9237-2011 NR 86 TC 27 Z9 27 U1 0 U2 9 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD JAN 10 PY 2000 VL 105 IS B1 BP 513 EP 529 DI 10.1029/1999JB900145 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 273YR UT WOS:000084737400008 ER PT J AU Swenson, JL Beck, SL Zandt, G AF Swenson, JL Beck, SL Zandt, G TI Crustal structure of the Altiplano from broadband regional waveform modeling: Implications for the composition of thick continental crust SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID CENTRAL ANDEAN PLATEAU; DEEP BOLIVIAN EARTHQUAKE; SUBDUCTED NAZCA PLATE; EASTERN CORDILLERA; VOLCANIC-ROCKS; MAGMA GENESIS; LITHOSPHERIC STRUCTURE; TIBETAN PLATEAU; CONTAMINATION; TECTONICS AB We have modeled the full waveforms from six intermediate-depth and two shallow earthquakes recorded at regional distances by the BANJO Broadband Andean Joint Experiment (BANJO) and Seismic Exploration of the Deep Altiplano (SEDA) portable seismic networks in the central Andes. In this study we utilize data from those BANJO and SEDA stations located within the Altiplano and Eastern Cordillera. We used reflectivity synthetic seismograms and a grid search to constrain four parameters of the Altiplano-Eastern Cordillera lithosphere: crustal thickness, average crustal velocity (V-p), and crustal and upper mantle Poisson's ratios (sigma(crust) and sigma(mantle)). Using our grid search, we investigated the crustal and upper mantle structure along 36 individual event station paths and applied forward modeling to 56 event station paths. Robust models for the Altiplano that provide the best overall fit between the data and synthetic seismograms are characterized by an average V-p of 5.75-6.25 km/s, crustal thicknesses of 60-65 km, sigma(crust) = 0.25, and sigma(mantle) = 0.27-0.29. We find a north-south variation in the structure of the Altiplano, with the crust south of the BANJO transect characterized by either lower than average crustal P wave velocities or a slightly higher sigma(crust) relative to crust north of the BANJO transect. These results are consistent with a model of crustal thickening caused predominantly by tectonic shortening of felsic crust, rather than by underplating or magmatic intrusion from the mantle. C1 Univ Arizona, Dept Geosci, So Arizona Seism Observ, Tucson, AZ 85721 USA. RP Swenson, JL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Geophys & Global Secur Div, L206,POB 808, Livermore, CA 94551 USA. NR 52 TC 50 Z9 52 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD JAN 10 PY 2000 VL 105 IS B1 BP 607 EP 621 DI 10.1029/1999JB900327 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 273YR UT WOS:000084737400013 ER PT J AU Benedetti, L Tapponnier, P King, GCP Meyer, B Manighetti, I AF Benedetti, L Tapponnier, P King, GCP Meyer, B Manighetti, I TI Growth folding and active thrusting in the Montello region, Veneto, northern Italy SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID FAULT-PLANE SOLUTIONS; SEA-LEVEL RECORD; NEW-ZEALAND; GEOMORPHIC EVIDENCE; MARINE TERRACES; STRIKE-SLIP; QILIAN-SHAN; EARTHQUAKE; TECTONICS; CALIFORNIA AB The Montello is an elongated hill about 15 km long and 5 km wide located south of the Venetian Alps front and similar to 100 km southwest of Gemona, site of the destructive M-s similar to 6, 1976 earthquake sequence, Mio-Pliocene strata in the core of the hill are folded. Seven Quaternary terraces across the western termination of the anticline have also been folded and uplifted. The terraces flank the abandoned Biadene valley, a former course of the Pia ire river which now flows eastwards along the north side of the hill. Topographic profiles along and transverse to the valley and terraces are used to measure the progressive development of the anticline. Fossil remains and archaeological sites dated with C-14 suggest that the Biadene paleovalley was abandoned between 14 and 8 ka (11 +/- 3 ka). The successive terraces appear to have been emplaced at the onset of interglacials and interstadials, since about 350 ka. The best fitting terrace ages suggest vertical uplift; rates of about 0.5 mm/yr before 17% ka and of about 1 mm/yr after 121 lia. The Montello thus appears to be a growing: ramp anticline on top of an active, north dipping thrust; that has migrated south of the mountain into the foreland. Modeling the deformation of the terraces as a result of motion on such a thrust ramp requires that it propagated both south and upwards with time but with a, constant; slip rate (1.8-2 mm/yr). For at least 300 kyr the lateral growth of the anticline kept pushing: the course of the Piave river southwestwards, at a rate at first of 10 mm/yr, and then 20 mm/yr, Though the growth rate doubled more than 120 kyr ago, the anticline kept a constant height/length growth ratio (similar or equal to 20) implying: self-similar depth/length growth of the thrust underneath. The clustering of historical earthquakes north of Treviso suggests that the thrust responsible for ongoing folding of the 'Montello slipped seismically three times (778, 1268, 1859 A.D.; intensity I greater than or equal to VIII) in the last 2000 years, with events of maximum magnitude close to 6 and with average recurrence time between 500 and 1000 years. NW shortening on NE-SW trending thrusts along: the Venetian Alps front is compatible with the direction of convergence between Africa and Europe but does not suffice to absorb this convergence. C1 CNRS, Inst Phys Globe, Lab Tecton, UMR 7578, Paris, France. RP Benedetti, L (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-202,POB 808, Livermore, CA 94550 USA. EM benedet@ipgp.jussieu.fr; tappon@ipgp.jussieu.fr; king@ipgp.jussieu.fr; meyer@ipgp.jussieu.fr; manig@ipgp.jussieu.fr RI Tapponnier, .Paul/B-7033-2011; Meyer, Bertrand/E-6903-2011 OI Tapponnier, .Paul/0000-0002-7135-1962; NR 76 TC 106 Z9 107 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD JAN 10 PY 2000 VL 105 IS B1 BP 739 EP 766 DI 10.1029/1999JB900222 PG 28 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 273YR UT WOS:000084737400022 ER PT J AU Boer, D Jakob, R Mulders, PJ AF Boer, D Jakob, R Mulders, PJ TI Angular dependences in electroweak semi-inclusive leptoproduction SO NUCLEAR PHYSICS B LA English DT Article ID DEEP-INELASTIC-SCATTERING; DRELL-YAN PROCESS; SINGLE SPIN ASYMMETRIES; AZIMUTHAL ASYMMETRY; PROTON-SCATTERING; ORDER 1/Q; DISTRIBUTIONS; FRAGMENTATION; ENERGIES; QCD AB We present the leading order unpolarized and polarized cross sections in electroweak semi-inclusive deep inelastic leptoproduction, The azimuthal dependences in the cross section differential in the transverse momentum of the vector boson arise due to intrinsic transverse momenta of the quarks. However, the presented asymmetries are not suppressed by inverse powers of the hard scale. We discuss the different opportunities to measure specific asymmetries as offered by neutral compared to charged current processes and point out the optimal kinematical regions. The present and (proposed) future HERA collider experiments would be most suitable for measuring some of the asymmetries discussed here, especially in case of Lambda production. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. Univ Pavia, I-27100 Pavia, Italy. Ist Nazl Fis Nucl, Sez Pavia, I-27100 Pavia, Italy. Free Univ Amsterdam, Dept Phys & Astron, NL-1081 HV Amsterdam, Netherlands. RP Boer, D (reprint author), Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RI Boer, Daniel/B-3493-2015; OI Boer, Daniel/0000-0003-0985-4662; Mulders, Piet/0000-0001-7678-6917 NR 30 TC 32 Z9 32 U1 0 U2 1 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 JAN 10 PY 2000 VL 564 IS 3 BP 471 EP 485 DI 10.1016/S0550-3213(99)00586-6 PG 15 WC Physics, Particles & Fields SC Physics GA 274HR UT WOS:000084760800007 ER PT J AU Albright, JN Dreesen, DS AF Albright, JN Dreesen, DS TI Microhole technology lowers reservoir exploration, characterization costs SO OIL & GAS JOURNAL LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Albright, JN (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 5 TC 2 Z9 2 U1 0 U2 0 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 JAN 10 PY 2000 VL 98 IS 2 BP 39 EP 41 PG 3 WC Energy & Fuels; Engineering, Petroleum SC Energy & Fuels; Engineering GA 275WW UT WOS:000084844000014 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M 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, B Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, BS Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C 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 Chang, PS Chang, PT 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 Cobal, V Cocca, E 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 Gadomski, S 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 Gouilianos, 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 Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, C Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kirk, M Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K 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, YG Lockyer, N Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Moggi, N Moore, E Morre, 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 Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D 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, S 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, N Spiegel, L Stanco, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takashima, R Takikawa, K Tanaka, M Takano, T 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 Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T 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 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 Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M 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, B Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, BS Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C 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 Chang, PS Chang, PT 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 Cobal, V Cocca, E 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 Gadomski, S 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 Gouilianos, 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 Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, C Iwai, J Iwata, Y James, E Jensen, H Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kirk, M Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K 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, YG Lockyer, N Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Moggi, N Moore, E Morre, 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 Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D 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, S 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, N Spiegel, L Stanco, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takashima, R Takikawa, K Tanaka, M Takano, T 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 Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T 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 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 helicity of W bosons in top quark decays SO PHYSICAL REVIEW LETTERS LA English DT Article ID PRODUCTION CROSS-SECTION; SILICON VERTEX DETECTOR; COLLIDER DETECTOR; P(P)OVER-BAR COLLISIONS; HADRON COLLIDERS; COUPLINGS; FERMILAB; POLARIZATION; B->S-GAMMA; TESTS AB We use the transverse momentum spectrum of leptons in the decay chain t --> bW with W --> l nu to measure the helicity of the W bosons in the top quark rest frame. Ourmeasurement uses a tt sample isolated in 106 +/- 4 pb(-1) of data collected in collisions at root s = 1.8 TeV with the CDF detector at the Fermilab Tevatron. Assuming a standard. V-A weak decay, we find that the fraction of W's with zero helicity in the top rest frame is F-0 = 0.91 +/- 0.37(stat) +/- 0.13(syst), consistent with the standard model prediction of F-0 = 0.70 for a top mass of 175 GeV/c(2). C1 Lawrence Orlando Berkeley Natl 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, Santander 39005, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Inst Nucl Res, 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. High Energy Accelerator Res Org KEK, 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. 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. Rutgers State Univ, Piscataway, NJ 08855 USA. Texas A&M Univ, College Stn, TX 77843 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. Texas Tech Univ, Lubbock, TX 79409 USA. Rockefeller Univ, New York, NY 10021 USA. Osaka City Univ, Osaka 588, Japan. RP Affolder, T (reprint author), Lawrence Orlando Berkeley Natl 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; vilar, rocio/P-8480-2014; Prokoshin, Fedor/E-2795-2012; vilar, rocio/D-7454-2014 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; Prokoshin, Fedor/0000-0001-6389-5399; NR 27 TC 55 Z9 55 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 10 PY 2000 VL 84 IS 2 BP 216 EP 221 DI 10.1103/PhysRevLett.84.216 PG 6 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500004 ER PT J AU Abbott, B Abolins, M Abramov, V Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Akimov, V Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Chen, W Cho, DK Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Fatyga, MK Feher, S Fein, B Ferbel, T Fisk, HE Fisyak, Y Flattum, E Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, P Gilmartin, R Ginther, G Gobbi, B Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, P Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Green, JA Greenlee, H Grinstein, S Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, A Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, HS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Ito, AS Jerger, SA Jesik, R Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Landry, F Landsberg, G Leflat, A Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lu, JG Lucotte, A Lueking, L Maciel, AKA Madaras, RJ Magana-Mendoza, L Manankov, V Mani, S Mao, HS Markeloff, R Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miao, C Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mostafa, M da Motta, H Nang, F Narain, P Narasimham, VS Neal, HA Negret, JP Norman, D Oesch, L Oguri, V Oshima, N Owen, D Padley, P Para, A Parashar, N Park, YM Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Rajagopalan, S Ramirez, O Reay, NW Reucroft, S Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, A Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Singh, P Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Song, XF Sosebee, M Sotnikova, N Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Toback, D Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Y Zanabria, M Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A AF Abbott, B Abolins, M Abramov, V Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Akimov, V Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Chen, W Cho, DK Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Fatyga, MK Feher, S Fein, B Ferbel, T Fisk, HE Fisyak, Y Flattum, E Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, P Gilmartin, R Ginther, G Gobbi, B Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, P Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Green, JA Greenlee, H Grinstein, S Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, A Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, HS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Ito, AS Jerger, SA Jesik, R Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Landry, F Landsberg, G Leflat, A Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lu, JG Lucotte, A Lueking, L Maciel, AKA Madaras, RJ Magana-Mendoza, L Manankov, V Mani, S Mao, HS Markeloff, R Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miao, C Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mostafa, M da Motta, H Nang, F Narain, P Narasimham, VS Neal, HA Negret, JP Norman, D Oesch, L Oguri, V Oshima, N Owen, D Padley, P Para, A Parashar, N Park, YM Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Rajagopalan, S Ramirez, O Reay, NW Reucroft, S Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, A Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Singh, P Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Song, XF Sosebee, M Sotnikova, N Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Toback, D Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Varelas, N Volkov, AA Vorobiev, AP Wahl, HD Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Y Zanabria, M Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A CA DO collaboration TI Measurement of the W boson mass using electrons at large rapidities SO PHYSICAL REVIEW LETTERS LA English DT Article ID PARTON DISTRIBUTIONS; RADIATIVE-CORRECTIONS; FERMILAB-TEVATRON; GLOBAL ANALYSIS; D0 DETECTOR; COLLISIONS; COLLIDER; DECAY AB We report a measurement of the W boson mass based on an integrated luminosity of 82 pb(-1) from collisions at root s = 1.8 TeV recorded in 1994-1995 by the D0 detector at the Fermilab Tevatron. We identify W bosons by their decays to ev, where the electron is detected in the forward calorimeters. We extract the mass by fitting the transverse mass and the electron and neutrino transverse momentum spectra of 11 089 W boson candidates. We measure M-w = 80.691 +/- 0.227 GeV. By combining this measurement with our previously published central calorimeter results from data taken in 1992-1993 and 1994-1995, we obtain M-w = 80.482 +/- 0.091 GeV. C1 Univ Buenos Aires, Buenos Aires, DF, Argentina. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. Univ Estado Rio de Janeiro, Rio De Janeiro, Brazil. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Los Andes, Bogota, Colombia. Univ San Francisco Quito, Quito, Ecuador. Univ Grenoble 1, IN2P3 CNRS, Inst Sci Nucl, Grenoble, France. Ctr Phys Particules Marseille, IN2P3 CNRS, Marseille, France. CEA, DAPNIA Serv Phys Particules, Saclay, France. Panjab Univ, Chandigarh 160014, India. Univ Delhi, Delhi 110007, India. Tata Inst Fundamental Res, Mumbai, India. Kyungsung Univ, Pusan 608736, South Korea. Seoul Natl Univ, Seoul, South Korea. CINVESTAV, Mexico City 14000, DF, Mexico. Inst Nucl Phys, Krakow, Poland. Inst Theoret & Expt Phys, Moscow 117259, Russia. Moscow State Univ, Moscow, Russia. Inst High Energy Phys, Protvino, Russia. Univ Lancaster, Lancaster, England. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Hawaii, Honolulu, HI 96822 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Illinois, Chicago, IL 60607 USA. No Illinois Univ, De Kalb, IL 60115 USA. Northwestern Univ, Evanston, IL 60208 USA. Indiana Univ, Bloomington, IN 47405 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Purdue Univ, W Lafayette, IN 47907 USA. Iowa State Univ, Ames, IA 50011 USA. Univ Kansas, Lawrence, KS 66045 USA. Kansas State Univ, Manhattan, KS 66506 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Univ Maryland, College Pk, MD 20742 USA. Boston Univ, Boston, MA 02215 USA. Northeastern Univ, Boston, MA 02115 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ Nebraska, Lincoln, NE 68588 USA. Columbia Univ, New York, NY 10027 USA. NYU, New York, NY 10003 USA. Univ Rochester, Rochester, NY 14627 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Langston Univ, Langston, OK 73050 USA. Univ Oklahoma, Norman, OK 73019 USA. Brown Univ, Providence, RI 02912 USA. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. Rice Univ, Houston, TX 77005 USA. Univ Washington, Seattle, WA 98195 USA. RP Abbott, B (reprint author), Univ Buenos Aires, Buenos Aires, DF, Argentina. RI Sznajder, Andre/L-1621-2016; Shivpuri, R K/A-5848-2010; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Leflat, Alexander/D-7284-2012; Dudko, Lev/D-7127-2012; Merkin, Mikhail/D-6809-2012; Yip, Kin/D-6860-2013; Kuleshov, Sergey/D-9940-2013; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013; Belyaev, Alexander/F-6637-2015 OI Sznajder, Andre/0000-0001-6998-1108; Kim, Sun Kee/0000-0002-0013-0775; Dudko, Lev/0000-0002-4462-3192; Yip, Kin/0000-0002-8576-4311; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489; Belyaev, Alexander/0000-0002-1733-4408 NR 30 TC 25 Z9 25 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 JAN 10 PY 2000 VL 84 IS 2 BP 222 EP 227 DI 10.1103/PhysRevLett.84.222 PG 6 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500005 ER PT J AU Babu, KS Kolda, C AF Babu, KS Kolda, C TI Higgs-mediated B-0 -> mu(+) mu(-) in minimal supersymmetry SO PHYSICAL REVIEW LETTERS LA English DT Article ID TOP-QUARK MASS; THRESHOLD CORRECTIONS; UNIFICATION; BREAKING; MATRIX AB We demonstrate a new source for flavor-changing neutral currents within the minimal supersymmetric standard model. At moderate to large tan beta, it is no longer possible to diagonalize the masses of the quarks in the same basis as their Yukawa couplings. This generates flavor-violating couplings of the form (b) over bar(R)d(L)phi and (b) over bar(R)S(L)phi where phi is any of the three neutral, physical Higgs bosons. These new couplings lead to rare processes in the B system such as B-0 --> mu(+) mu(-) and B-0 - (B) over bar(0) mixing. We show that the tatter are anomalously suppressed, while the former is in the experimentally interesting range, with an observable signal possible at Run II of the Tevatron if m(A) less than or similar to 400-700 GeV. C1 Oklahoma State Univ, Dept Phys, Stillwater, OK 74078 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theory Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Babu, KS (reprint author), Oklahoma State Univ, Dept Phys, Stillwater, OK 74078 USA. NR 21 TC 371 Z9 374 U1 0 U2 0 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 JAN 10 PY 2000 VL 84 IS 2 BP 228 EP 231 DI 10.1103/PhysRevLett.84.228 PG 4 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500006 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M 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, BS Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Borras, K Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C 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 Chang, PS Chang, PT 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 Cobal, M Cocca, E Connolly, A Conway, J Cooper, J Cordelli, M de Costa, JG 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 Gadomski, S Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, 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 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 Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M 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, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K 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 Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, C Martin, A Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Moggi, N Moor, 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 Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Sakumota, 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 Takashima, R Takikawa, K Tanaka, M Takano, T 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 Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T 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 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 Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M 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, BS Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Borras, K Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C 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 Chang, PS Chang, PT 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 Cobal, M Cocca, E Connolly, A Conway, J Cooper, J Cordelli, M de Costa, JG 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 Gadomski, S Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, 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 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 Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incagli, M 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, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K 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 Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, C Martin, A Matthews, JAJ Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Meschi, E Mesropian, C Miao, C Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Moggi, N Moor, 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 Parri, A Partos, D Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Prokoshin, F Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Sakumota, 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 Takashima, R Takikawa, K Tanaka, M Takano, T 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 Truitt, S Tseng, J Turini, N Ukegawa, F Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Vologouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Watanabe, T 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 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 Observation of diffractive b-quark production at the Fermilab, Tevatron SO PHYSICAL REVIEW LETTERS LA English DT Article ID SILICON VERTEX DETECTOR; COLLIDER; PHYSICS; POMERON AB We report a measurement of the fraction of b quarks produced diffractively in (p) over bar p collisions at root s = 1.8 TeV. Diffraction is identified by the absence of particles in a forward pseudorapidity region. From events with an electron of transverse momentum 9.5 < p(T)(e) < 20 GeV/c within the pseudorapidity region \eta\ < 1.1, the ratio of diffractive to total b-quark production rates is found to be R-(b) over bar b = [0.62 +/- 0.19(stat) +/- 0.16(syst)]%. This result is comparable in magnitude to corresponding ratios for W and dijet production but significantly lower than expectations based on factorization. C1 Ernest Orlando Berkeley Natl 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 Inst Nucl Res, 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. High Energy Accelerator Res Org KEK, 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 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), Ernest Orlando Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Introzzi, Gianluca/K-2497-2015; vilar, rocio/D-7454-2014; 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; Prokoshin, Fedor/E-2795-2012 OI Introzzi, Gianluca/0000-0002-1314-2580; 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; Prokoshin, Fedor/0000-0001-6389-5399 NR 21 TC 41 Z9 41 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 JAN 10 PY 2000 VL 84 IS 2 BP 232 EP 237 DI 10.1103/PhysRevLett.84.232 PG 6 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500007 ER PT J AU Back, CA Bauer, JD Landen, OL Turner, RE Lasinski, BF Hammer, JH Rosen, MD Suter, LJ Hsing, WH AF Back, CA Bauer, JD Landen, OL Turner, RE Lasinski, BF Hammer, JH Rosen, MD Suter, LJ Hsing, WH TI Detailed measurements of a diffusive supersonic wave in a radiatively heated foam SO PHYSICAL REVIEW LETTERS LA English DT Article ID SOFT X-RAYS; LASER-LIGHT; CONVERSION; PLASMAS AB We have made the first detailed measurements of a diffusive supersonic radiation wave in the laboratory. A 10 mg/cm(3) SiO2 foam is radiatively heated by the x-ray flux from a laser-irradiated hohlraum. The resulting radiation wave propagates axially through the optically thick foam and is measured via time-resolved x-ray imaging as it breaks out the far end. The data show that the radiation wave breaks out at the center prior to breaking out at the edges, indicating a significant curvature in the radiation front. This curvature is primarily due to energy loss into the walls surrounding the foam. 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 16 TC 38 Z9 46 U1 1 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 JAN 10 PY 2000 VL 84 IS 2 BP 274 EP 277 DI 10.1103/PhysRevLett.84.274 PG 4 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500017 ER PT J AU Pesme, D Rozmus, W Tikhonchuk, VT Maximov, A Ourdev, I Still, CH AF Pesme, D Rozmus, W Tikhonchuk, VT Maximov, A Ourdev, I Still, CH TI Resonant instability of laser filaments in a plasma SO PHYSICAL REVIEW LETTERS LA English DT Article ID LIGHT AB The stability of nonlinear laser light filaments in a homogeneous isothermal plasma with respect to coupled electromagnetic and density perturbations is examined. In addition to the previously known modulational instability of trapped electromagnetic mode, a new fast growing resonant instability is found. It corresponds to the growth of an excited eigenmode in the waveguide formed by the filament density depletion, the associated density response being supersonic and transversally localized. The evolution of the instability is illustrated by numerical simulations in two and three spatial dimensions. C1 Ecole Polytech, Ctr Phys Theor, F-91128 Palaiseau, France. Univ Alberta, Dept Phys, Inst Phys Theor, Edmonton, AB T6G 2J1, Canada. Russian Acad Sci, PN Lebedev Phys Inst, Moscow 117924, Russia. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. RP Ecole Polytech, Ctr Phys Theor, F-91128 Palaiseau, France. NR 12 TC 43 Z9 43 U1 1 U2 4 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 JAN 10 PY 2000 VL 84 IS 2 BP 278 EP 281 DI 10.1103/PhysRevLett.84.278 PG 4 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500018 ER PT J AU Wade, MR Houlberg, WA Baylor, LR AF Wade, MR Houlberg, WA Baylor, LR TI Experimental confirmation of impurity convection driven by the ion-temperature gradient in toroidal plasmas SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIII-D TOKAMAK; NEOCLASSICAL TRANSPORT; HELIUM TRANSPORT; CONFINEMENT; REGIME; PROFILES AB Strong, outward convection of low-Z impurity ions has been observed in DIII-D plasmas which have reduced anomalous transport, a weak density gradient, and a strong ion;temperature gradient. Comparing the measurements with theoretical predictions of collisional (neoclassical) transport indicates that the observed outward convection results from an effect known as "temperature screening." Taking into account the non-negligible effect of anomalous transport, quantitative agreement is found between the measured transport properties and the predicted values, including the strong Z dependence. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Wade, MR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 21 TC 41 Z9 41 U1 1 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 JAN 10 PY 2000 VL 84 IS 2 BP 282 EP 285 DI 10.1103/PhysRevLett.84.282 PG 4 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500019 ER PT J AU Putz, M Kremer, K Everaers, R AF Putz, M Kremer, K Everaers, R TI Self-similar chain conformations in polymer gels SO PHYSICAL REVIEW LETTERS LA English DT Article ID ANGLE NEUTRON-SCATTERING; MODEL NETWORKS; MONTE-CARLO; POLY(DIMETHYLSILOXANE) NETWORKS; SWELLING BEHAVIOR; EQUILIBRIUM; SIMULATION; ELASTICITY; RELAXATION; MODULUS AB We use molecular dynamics simulations to study the swelling of randomly end-cross-linked polymer networks in good solvent conditions. We find that the equilibrium degree of swelling saturates at Q(eq) approximate to N-e(3/5) for mean strand lengths (N) over bar(s) exceeding the melt entanglement length N,. The internal structure of the network strands in the swollen state is characterized by a new exponent nu = 0.72 +/- 0.02. Our findings can be rationalized by a Flory argument for a self-similar structure of mutually interpenetrating network strands, agree partially with the classical Flory-Rehner theory, and are in contradiction to de Gennes' c*-theorem. C1 Max Planck Inst Polymerforsch, D-55021 Mainz, Germany. RP Putz, M (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Kremer, Kurt/G-5652-2011; Everaers, Ralf/K-2228-2013; MPIP, Theory/I-9884-2014 OI Everaers, Ralf/0000-0002-6843-2753; NR 43 TC 41 Z9 41 U1 4 U2 22 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 JAN 10 PY 2000 VL 84 IS 2 BP 298 EP 301 DI 10.1103/PhysRevLett.84.298 PG 4 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500023 ER PT J AU Jesson, DE Kastner, M Voigtlander, B AF Jesson, DE Kastner, M Voigtlander, B TI Direct observation of subcritical fluctuations during the formation of strained semiconductor islands SO PHYSICAL REVIEW LETTERS LA English DT Article ID SI(001) HOMOEPITAXIAL GROWTH; MOLECULAR-BEAM EPITAXY; MICROSTRUCTURAL EVOLUTION; HETEROEPITAXIAL GROWTH; SHAPE TRANSITION; QUANTUM DOTS; IN-SITU; GE; NUCLEATION; RELAXATION AB We have directly imaged subcritical fluctuations during the nucleation phase of three-dimensional islands in strained layer epitaxy. The fluctuations are defect mediated and are found to be large even at low growth temperatures. We attribute the existence of large fluctuations to the time dependence of the supersaturation. This indicates classical nucleation concepts are relevant, even at low growth temperatures. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Forschungszentrum Julich, Inst Grenzflachenforsch & Vakuumphys, D-52425 Julich, Germany. RP Jesson, DE (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Voigtlander, Bert/B-2156-2008; OI Voigtlander, Bert/0000-0001-9580-7031; Jesson, David/0000-0003-0897-1445 NR 33 TC 78 Z9 79 U1 1 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 10 PY 2000 VL 84 IS 2 BP 330 EP 333 DI 10.1103/PhysRevLett.84.330 PG 4 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500031 ER PT J AU Romberg, R Heckmair, N Frigo, SP Ogurtsov, A Menzel, D Feulner, P AF Romberg, R Heckmair, N Frigo, SP Ogurtsov, A Menzel, D Feulner, P TI Atom-selective bond breaking in a chemisorbed homonuclear molecule induced by core excitation: N-2/Ru(001) SO PHYSICAL REVIEW LETTERS LA English DT Article ID K-SHELL PHOTOABSORPTION; N-2; NI(100); SPECTRA; DEPENDENCE; ADSORBATES; N2 AB We observe photochemical selectivity for N 1s to pi* excitations of chemisorbed N-2. By narrow bandwidth synchrotron radiation we selectively excite one of the two atoms of the molecule. Photon stimulated desorption of neutral N atoms predominates for excitations of the N atom close to the surface, whereas excitation of the outer atom ejects predominantly N-2(0) and small amounts of N+, demonstrating the predominant breaking of the inner or outer bond, respectively, of the N-2 adsorbate. Analysis on the basis of previously obtained decay electron spectra after atom-selective excitation can explain the mechanism of localized bond breaking. C1 Tech Univ Munich, Phys Dept E 20, D-85747 Garching, Germany. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Verkin Inst Low Temp Phys & Engn, UA-31064 Kharkov, Ukraine. RP Romberg, R (reprint author), Tech Univ Munich, Phys Dept E 20, D-85747 Garching, Germany. RI Ogurtsov, Alexander/A-9601-2016; OI Ogurtsov, Alexander/0000-0003-4688-6428; Menzel, Dietrich/0000-0002-7188-8532 NR 22 TC 40 Z9 41 U1 0 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 10 PY 2000 VL 84 IS 2 BP 374 EP 377 DI 10.1103/PhysRevLett.84.374 PG 4 WC Physics, Multidisciplinary SC Physics GA 272QB UT WOS:000084661500042 ER PT J AU Greenblatt, BJ Zanni, MT Neumark, DM AF Greenblatt, BJ Zanni, MT Neumark, DM TI Femtosecond photoelectron spectroscopy of I-2(-)(CO2)(n) clusters (n=4, 6, 9, 12, 14, 16) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID NONADIABATIC MOLECULAR-DYNAMICS; GEMINATE RECOMBINATION DYNAMICS; VIBRATIONAL-RELAXATION; CHARGE FLOW; SOLVENT DYNAMICS; PHOTODISSOCIATION; IONS; I-2(-); I2; I-2(-)CENTER-DOT-AR-N AB The photodissociation dynamics of I-2(-)(CO2)(n)(n=4-16) clusters excited at 780 nm have been studied with femtosecond photoelectron spectroscopy (FPES). The range of cluster sizes spans the uncaged and fully-caged product limits for this reaction. We observe time scales for a variety of processes in these clusters, including dissociation of the I-2(-) chromophore, solvation of the I- fragment, the onset of recombination on the ground state of I-2(-), vibrational relaxation, and solvent evaporation. In addition, substantial trapping in a "solvent-separated" state is seen for clusters with n greater than or equal to 9; this state persists for at least 200 ps, the longest time delay probed here. Simulations of the spectra were performed in order to determine the time dependence of the electronic state populations, the I-2(-) vibrational distribution, and the number of CO2 molecules in the cluster. Results are compared to previous experimental and theoretical studies of I-2(-)(CO2)(n) photodissociation, and to a recent FPES study of I-2(-)(Ar)(n) clusters. (C) 2000 American Institute of Physics. [S0021-9606(00)00102-1]. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Greenblatt, BJ (reprint author), NASA, Ames Res Ctr, Atmospher Chem & Dynam Branch, Mail Stop 245-5, Moffett Field, CA 94035 USA. RI Zanni, Martin/K-2707-2013; Neumark, Daniel/B-9551-2009 OI Neumark, Daniel/0000-0002-3762-9473 NR 43 TC 35 Z9 35 U1 3 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2000 VL 112 IS 2 BP 601 EP 612 DI 10.1063/1.480685 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 269ZB UT WOS:000084507000014 ER PT J AU Lee, SH Cummings, PT AF Lee, SH Cummings, PT TI Molecular dynamics simulation of limiting conductances for LiCl, NaBr, and CsBr in supercritical water SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID AQUEOUS-SOLUTIONS; ALKALI-METAL; POTENTIALS; IONS; 600-DEGREES-C; 25-DEGREES-C; SOLVATION; MOBILITY; FLOW; NACL AB We report molecular dynamics simulations of LiCl, NaBr, and CsBr in supercritical water in order to explain the experimental observations of the limiting conductances as a function of the density of water at supercritical state points. As was the case in our previous work on NaCl in supercritical water [Lee et al., Chem. Phys. Lett. 293, 289 (1998)], we find that the experimental trends in the limiting conductances as a function of water density are reproduced in our simulations-a clear change of slope from the assumed linear dependence of limiting conductances of LiCl, NaBr, and CsCl on the water density. We also found that the effect of the number of hydration water molecules around ions dominates in the higher-density region while the interaction strength between the ions and the hydration water molecules (as measured by the potential energy per hydration water molecule) dominates in the lower-density region. In the case of Cs+ and Br-, however, the latter factor in the lower-density region is not as dominant as in the cases of Na+ and Cl- since a clear difference between the potential energy per hydration water molecule at densities above and below 0.45 g/cm(3) was not clearly observed in the cases. In the case of Li+, the interaction between the ions and the hydration water in the lower-density region is almost a nonfactor since the potential energy per hydration water molecule is monotonically decreased with decreasing water density, which is consistent with the linear increase of the limiting conductance for the Li+ ion with decreasing water density. (C) 2000 American Institute of Physics. [S0021-9606(00)50701-6]. C1 Kyungsung Univ, Dept Chem, Pusan 608736, South Korea. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Lee, SH (reprint author), Kyungsung Univ, Dept Chem, Pusan 608736, South Korea. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 27 TC 42 Z9 42 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2000 VL 112 IS 2 BP 864 EP 869 DI 10.1063/1.480613 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 269ZB UT WOS:000084507000043 ER PT J AU Dvorak, J Dai, HL AF Dvorak, J Dai, HL TI Optical reflectivity changes induced by adsorption on metal surfaces: The origin and applications to monitoring adsorption kinetics SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID BAND INFRARED REFLECTANCE; ADSORBATE-INDUCED CHANGES; EFFECT FREQUENCY REGION; ABSORPTION SPECTROSCOPY; LATERAL INTERACTIONS; DESORPTION-KINETICS; CU(100) SURFACE; CO; CU; ACETYLENE AB It is observed that when a monolayer of CO and acetylene is chemisorbed on the Cu(100) surface, the reflectivity of the metal surface at the He-Ne laser wavelength of 632 nm is reduced on the order of 1%, while the physisorption of water, methanol, and acetone induces a reflectivity change on the order of 0.01%. The small reflectivity change induced by physisorption can be described by a three-layer model taking into account the molecular layer refractive index. The much bigger reflectivity change induced by the chemisorbed adsorbates, on the other hand, is a result of bonding perturbations to the electronic structure of the metal surface layer. The latter is supported by an electron scattering model description of the reflectivity change up to 1.96 eV on Cu. For both CO and acetylene, the optical reflectivity change is found to be linearly proportional to the submonolayer coverage. The phenomenon thus offers an excellent method to measure surface kinetics. It is found from the reflectivity change measurements that the initial sticking coefficient for both adsorbates is nearly unity at 110 K; 0.85 for CO and 1.0 for acetylene. The temperature and coverage dependence of the sticking coefficient shows that the adsorption behavior of both molecules is well described as direct adsorption mediated with an extrinsic precursor. For acetylene adsorption, the sticking coefficient shows little dependence on the substrate temperature suggesting that the "extrinsic precursor" is not a thermally equilibrated species. For CO, the transition into a compression phase beyond 0.5 ML results in a corresponding change in the sticking coefficient deduced from the reflectivity data. (C) 2000 American Institute of Physics. [S0021-9606(00)70402-8]. C1 Univ Penn, Dept Chem, Philadelphia, PA 19104 USA. RP Dvorak, J (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 70 TC 20 Z9 20 U1 0 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2000 VL 112 IS 2 BP 923 EP 934 DI 10.1063/1.480722 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 269ZB UT WOS:000084507000049 ER PT J AU Rodriguez, JA Hanson, JC Chaturvedi, S Maiti, A Brito, JL AF Rodriguez, JA Hanson, JC Chaturvedi, S Maiti, A Brito, JL TI Phase transformations and electronic properties in mixed-metal oxides: Experimental and theoretical studies on the behavior of NiMoO4 and MgMoO4 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MAGNESIUM MOLYBDATE CATALYSTS; TOTAL-ENERGY CALCULATIONS; RAY-POWDER DIFFRACTION; OXIDATIVE DEHYDROGENATION; FIRST-PRINCIPLES; EXCHANGE; ZEOLITES; PROPANE; APPROXIMATION; PRECURSOR AB Mixed-metal oxides play a relevant role in many areas of chemistry, physics, and materials science. We have examined the structural and electronic properties of NiMoO4 and MgMoO4 by means of synchrotron-based time-resolved x-ray diffraction (XRD), x-ray absorption near-edge spectroscopy (XANES), and first-principles density functional theory (DFT) calculations. Nickel molybdate can exist in two phases (alpha and beta). Mo is in a near tetrahedral environment in the beta-phase, whereas in the alpha-phase the metal exhibits a pseudo-octahedral coordination with two very long Mo-O distances (2.3-2.4 Angstrom). The results of DFT calculations indicate that the alpha-phase of NiMoO4 is similar to 9 kcal/mol more stable than the beta-phase. On the other hand, in the case of magnesium molybdate, an alpha-NiMoO4-type phase is similar to 13 kcal/mol less stable than beta-MgMoO4. These trends in stability probably result from variations in the metal-metal repulsion within the alpha-phases of the compounds. For the alpha -->beta transition in NiMoO4, the DFT calculations predict an energy barrier of similar to 50 kcal/mol. An apparent activation energy of similar to 80 kcal/mol can be derived from the time-resolved XRD experiments. The degree of ionicity in MgMoO4 is larger than that in NiMoO4. The nickel molybdate displays a large density of states near the top of the valence band that is not observed in the magnesium molybdate. This makes NiMoO4 more chemically active than MgMoO4. A similar type of correlation is found between the electronic and chemical properties of NiMoO4, CoMoO4, and FeMoO4. The DFT results and Mo L-II-edge XANES spectra show big differences in the splitting of the Mo 4d orbitals in the alpha- and beta-phases of the molybdates. The line shape in the O K-edge essentially reflects the behavior seen for the 4d orbitals in the Mo L-II-edge (i.e., mainly O 1s --> Mo 4d electronic transitions). The Mo L-II- and O K-edges in XANES can be very useful for probing the local symmetry of Mo atoms in mixed-metal oxides. (C) 2000 American Institute of Physics. [S0021-9606(00)70702-1]. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Mol Simulat Inc, San Diego, CA 92121 USA. Inst Venezolano Invest Cient, Ctr Quim, Caracas 1020A, Venezuela. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Brito, Joaquin/F-4974-2010; Hanson, jonathan/E-3517-2010 NR 53 TC 74 Z9 74 U1 5 U2 61 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 8 PY 2000 VL 112 IS 2 BP 935 EP 945 DI 10.1063/1.480619 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 269ZB UT WOS:000084507000050 ER PT J AU Dillon, AC Parilla, PA Alleman, JL Perkins, JD Heben, MJ AF Dillon, AC Parilla, PA Alleman, JL Perkins, JD Heben, MJ TI Controlling single-wall nanotube diameters with variation in laser pulse power SO CHEMICAL PHYSICS LETTERS LA English DT Article ID CARBON NANOTUBES; VIBRATIONAL-MODES; RAMAN-SCATTERING; LARGE-SCALE; GROWTH; SPECTROSCOPY; CLUSTERS; GRAPHITE; PLASMA AB We demonstrate that laser peak pulse power can be employed to tune carbon single wall nanotube (SWNT) diameters. The production of SWNTs was investigated at room temperature and at 1200 degrees C. The diameters were shifted to smaller sizes in both cases as the pulse power was increased. SWNT size distributions and yields were studied with Raman spectroscopy and transmission electron microscopy. The evolution of the material quality with laser energy parameters offers insight in to SWNT formation mechanisms. These studies should aid in the development of methods for the rational control of SWNT growth. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Heben, MJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 23 TC 72 Z9 74 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 7 PY 2000 VL 316 IS 1-2 BP 13 EP 18 DI 10.1016/S0009-2614(99)01259-2 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 275UY UT WOS:000084839600003 ER PT J AU Ruscic, B Litorja, M AF Ruscic, B Litorja, M TI Photoionization of HOCO revisited: a new upper limit to the adiabatic ionization energy and lower limit to the enthalpy of formation SO CHEMICAL PHYSICS LETTERS LA English DT Article ID GAS-PHASE BASICITIES; MOLECULAR-STRUCTURE; PROTON AFFINITIES; FREE-RADICALS; SPECTRUM; RANGE; HEATS; OH; CO AB A new upper limit to the adiabatic ionization energy of trans-hydroxyoxomethyl, EI(t-HOCO) less than or equal to 8.195 +/- 0.022 eV, is provided, producing a lower limit to the enthalpy of formation, Delta H(f0)degrees(t-HOCO) greater than or equal to - 45.8 +/- 0.7 kcal/mol (greater than or equal to - 46.5 +/- 0.7 kcal/mol at 298 K). The spectrum shows progressions in C=O and C-O stretches of HOCO+ and provides evidence for the excitation of OCO bend. In addition, the data tentatively suggest an ionization onset as low as 8.06 +/- 0.03 eV. While it is not clear whether the latter corresponds to cis or trans isomer, it may indicate that Delta H(f0)degrees(HOCO) is even higher. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Ruscic, B (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Ruscic, Branko/A-8716-2008 OI Ruscic, Branko/0000-0002-4372-6990 NR 36 TC 51 Z9 51 U1 5 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 7 PY 2000 VL 316 IS 1-2 BP 45 EP 50 DI 10.1016/S0009-2614(99)01267-1 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 275UY UT WOS:000084839600008 ER PT J AU Sordo, JA AF Sordo, JA TI On the important role played by polarization functions in calculations involving hypervalent molecules SO CHEMICAL PHYSICS LETTERS LA English DT Article ID BASIS-SET REQUIREMENTS; ATOMIZATION ENERGIES; GAUSSIAN-2; ATOMS; CONVERGENCE; 1ST-ROW; SO2 AB It is shown that special care must be taken to choose a basis set with an appropriate number of polarization functions when studying processes involving several hypervalent molecules, each with some particular atom exhibiting different Lewis structures. The reaction between 1,3 butadiene and sulfur dioxide rendering either sultines or sulfolenes, depending on the experimental conditions, serves as an illustration. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Oviedo, Fac Quim, Dept Quim Fis, Lab Quim Comp, Oviedo 33006, Spain. RP Sordo, JA (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, 906 Battelle Blvd, Richland, WA 99352 USA. NR 16 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 7 PY 2000 VL 316 IS 1-2 BP 167 EP 170 DI 10.1016/S0009-2614(99)01274-9 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 275UY UT WOS:000084839600026 ER PT J AU Zhou, XD Wang, JH Shukla, A Futrell, J AF Zhou, XD Wang, JH Shukla, A Futrell, J TI A tandem mass spectrometry study of the role of electronically excited states in the collision-induced dissociation of the hexafluorobenzene molecular cation SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE tandem mass spectrometry; collision-induced dissociation; hexafluorobenzene cation; electronic excitation; energy transfer; kinetic energy release ID ACTIVATED DISSOCIATION; ION; ENERGY; BEAM; DYNAMICS AB Dissociation of hexafluorobenzene cations via C-F bond cleavage following collisional activation with helium and argon has been studied at 1-4 keV (nominal) laboratory kinetic energies, When hexafluorobenzene cations are formed by 70 eV electrons, the kinetic energy distributions of the fragment ion, C6F5+, differ dramatically in that helium collisions proceed via highly endothermic channel whereas argon collisions result in a highly exothermic channel. Both processes are accompanied by a common dissociation pathway, which is nearly thermoneutral. With low energy electron ionization of C6F6 and argon collision gas the superelastic peak disappears and an endothermic process analogous to that resulting from helium collisional activation appears. These experimental observations suggest that 70 eV electrons result in the formation of hexafluorobenzene cations in electronically excited state(s) that have radiative lifetimes exceeding 20 mu s. The exothermic process corresponds to energy release of similar to 10 eV into translational mode during the collision and the endothermic process corresponds to transfer of similar to 17 eV energy from translational to internal modes. Since the threshold for dissociation is 7 eV, we suggest that both endothermic and exothermic channels proceed via the same electronically excited hypersurface. (Int J Mass Spectrom 194 (2000) 171-179) (C) 2000 Elsevier Science B.V. C1 Univ Delaware, Dept Chem & Biochem, Newark, DE 19716 USA. RP Shukla, A (reprint author), Pacific NW Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. NR 16 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD JAN 7 PY 2000 VL 194 IS 2-3 BP 171 EP 179 DI 10.1016/S1387-3806(99)00143-8 PG 9 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 270EW UT WOS:000084523300010 ER PT J AU Alcock, C AF Alcock, C TI The dark halo of the Milky Way SO SCIENCE LA English DT Review ID LARGE-MAGELLANIC-CLOUD; MICROLENSING EVENTS; ROTATION CURVE; GALACTIC HALO; GALAXY; MATTER; MASS; STARS AB Most of the matter in the Milky Way is invisible to astronomers. Precise numbers are elusive, but it appears that the dark component is 20 times as massive as the visible disk of stars and gas. This dark matter is distributed in space differently than the stars, forming a vast, diffuse halo, more spherical than disklike, which occupies more than 1000 times the volume of the disk of stars. The composition of this dark halo is unknown, but it may comprise a mixture of ancient, degenerate dwarf stars and exotic, hypothetical elementary particles. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Alcock, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, 700 East Ave,Mail Code L-051, Livermore, CA 94550 USA. NR 46 TC 15 Z9 15 U1 3 U2 4 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 7 PY 2000 VL 287 IS 5450 BP 74 EP 79 DI 10.1126/science.287.5450.74 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 271DG UT WOS:000084578400038 ER PT J AU Denschlag, J Simsarian, JE Feder, DL Clark, CW Collins, LA Cubizolles, J Deng, L Hagley, EW Helmerson, K Reinhardt, WP Rolston, SL Schneider, BI Phillips, WD AF Denschlag, J Simsarian, JE Feder, DL Clark, CW Collins, LA Cubizolles, J Deng, L Hagley, EW Helmerson, K Reinhardt, WP Rolston, SL Schneider, BI Phillips, WD TI Generating solitons by phase engineering of a Bose-Einstein condensate SO SCIENCE LA English DT Article ID BRAGG SCATTERING; ATOMS; COLLISIONS; WAVES AB Quantum phase engineering is demonstrated with two techniques that allow the spatial phase distribution of a Bose-Einstein condensate (BEC) to be written and read out. A quantum state was designed and produced by optically imprinting a phase pattern onto a BEC of sodium atoms, and matter-wave interferometry with spatially resolved imaging was used to analyze the resultant phase distribution. An appropriate phase imprint created solitons, the first experimental realization of this nonlinear phenomenon in a BEC. The subsequent evolution of these excitations was investigated both experimentally and theoretically. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Oxford, Oxford OX1 3PU, England. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Ecole Normale Super, F-75231 Paris, France. Univ Washington, Dept Chem, Seattle, WA 98195 USA. Natl Sci Fdn, Div Phys, Arlington, VA 22230 USA. RP Denschlag, J (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI Hecker Denschlag, Johannes/B-6047-2008; Clark, Charles/A-8594-2009; Deng, Lu/B-3997-2012; Hagley, Edward/B-4285-2012; Helmerson, Kristian/E-3683-2013; rolston, steven/L-5175-2013 OI Hecker Denschlag, Johannes/0000-0003-1984-4994; Clark, Charles/0000-0001-8724-9885; rolston, steven/0000-0003-1671-4190 NR 34 TC 862 Z9 873 U1 4 U2 45 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 7 PY 2000 VL 287 IS 5450 BP 97 EP 101 DI 10.1126/science.287.5450.97 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 271DG UT WOS:000084578400042 ER PT J AU Egolf, DA AF Egolf, DA TI Equilibrium regained: From nonequilibrium chaos to statistical mechanics SO SCIENCE LA English DT Article ID RAYLEIGH-BENARD CONVECTION; SPIRAL-DEFECT CHAOS; SPATIOTEMPORAL CHAOS; TRANSITION; COMPETITION; TURBULENCE AB Far-from-equilibrium, spatially extended chaotic systems have generally eluded analytical solution, leading researchers to consider theories based on a statistical rather than a detailed knowledge of the microscopic Length scales. Building on the recent discovery of a separation of length scales between macroscopic behavior and microscopic chaos, a simple far-from-equilibrium spatially extended chaotic system has been studied computationally at intermediate, coarse-grained scales. Equilibrium properties such as Gibbs distributions and detailed balance are recovered at these scales, which suggests that the macroscopic behavior of some far-from-equilibrium systems might be understood in terms of equilibrium statistical mechanics. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies MS B258, Div Theoret, Los Alamos, NM 87545 USA. RP Egolf, DA (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies MS B258, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. NR 24 TC 58 Z9 59 U1 1 U2 13 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JAN 7 PY 2000 VL 287 IS 5450 BP 101 EP 104 DI 10.1126/science.287.5450.101 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 271DG UT WOS:000084578400043 PM 10615038 ER PT J AU Li, NY Chang, PC Baca, AG Xie, XM Sharps, PR Hou, HQ AF Li, NY Chang, PC Baca, AG Xie, XM Sharps, PR Hou, HQ TI DC characteristics of MOVPE-grown Npn InGaP/InGaAsN DHBTs SO ELECTRONICS LETTERS LA English DT Article AB The authors have demonstrated, for the first time, a functional Npn double heterojunction bipolar transistor using a novel material, InGaAsN, with a bandgap energy of 1.2 eV as the p-type base layer. A 300 Angstrom thick InxGa1-xAs graded layer was introduced to reduce the conduction band offset at the p-type InGaAsN base and n-type GaAs collector junction. For an emitter size of 500 mu m(2), a peak current gain of 5.3 has been achieved. C1 EMCORE Corp, Emcore PhotoVoltaics, Albuquerque, NM 87123 USA. Sandia Natl Labs, Albuquerque, NM 87123 USA. RP Li, NY (reprint author), EMCORE Corp, Emcore PhotoVoltaics, 10240 Res Rd SE, Albuquerque, NM 87123 USA. NR 5 TC 37 Z9 38 U1 0 U2 1 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD JAN 6 PY 2000 VL 36 IS 1 BP 81 EP 83 DI 10.1049/el:20000024 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 279MN UT WOS:000085048400057 ER PT J AU Huffman, PR Brome, CR Butterworth, JS Coakley, KJ Dewey, MS Dzhosyuk, SN Golub, R Greene, GL Habicht, K Lamoreaux, SK Mattoni, CEH McKinsey, DN Wietfeldt, FE Doyle, JM AF Huffman, PR Brome, CR Butterworth, JS Coakley, KJ Dewey, MS Dzhosyuk, SN Golub, R Greene, GL Habicht, K Lamoreaux, SK Mattoni, CEH McKinsey, DN Wietfeldt, FE Doyle, JM TI Magnetic trapping of neutrons SO NATURE LA English DT Article ID ULTRACOLD NEUTRONS; COLD NEUTRONS; SUPERFLUID-HELIUM; ATOMIC-HYDROGEN; LIFETIME; STORAGE; HE-4; UCN AB Accurate measurement of the lifetime of the neutron (which is unstable to beta decay) is important for understanding the weak nuclear force(1) and the creation of matter during the Big Bang(2). Previous measurements of the neutron lifetime have mainly been limited by certain systematic errors(3); however, these could in principle be avoided by performing measurements on neutrons stored in a magnetic tray. Neutral-particle and charged-particle traps are widely used for studying both composite and elementary particles, because they allow long interaction times and isolation of particles from perturbing environments(4). Here,ve report the magnetic trapping of neutrons. The trapping region is filled with superfluid He-4, which is used to load neutrons into the trap and as a scintillator to detect their decay. Neutrons in the trap have a lifetime of 750(-200)(+330) seconds, mainly limited by their beta decay rather than trap losses. Our experiment verifies theoretical predictions regarding the loading process and magnetic trapping of neutrons. Further refinement of this method should lead to improved precision in the neutron lifetime measurement. C1 Harvard Univ, Cambridge, MA 02138 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Huffman, PR (reprint author), Harvard Univ, 17 Oxford St, Cambridge, MA 02138 USA. RI Habicht, Klaus/K-3636-2013; OI Habicht, Klaus/0000-0002-9915-7221; Huffman, Paul/0000-0002-2562-1378 NR 30 TC 79 Z9 79 U1 0 U2 5 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JAN 6 PY 2000 VL 403 IS 6765 BP 62 EP 64 DI 10.1038/47444 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 273BM UT WOS:000084687400040 ER PT J AU Breitweg, J Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Pellegrino, A Repond, J Stanek, R Yoshida, R Mattingly, MCK Abbiendi, G Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Coppola, N Corradi, M De Pasquale, S Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Eckert, M Hartmann, H Heinloth, K Hilger, E Jakob, HP Kappes, A Katz, UF Kerger, R Paul, E Rautenberg, J Schnurbusch, H Stifutkin, A Tandler, J Weber, A Wieber, H Bailey, DS Barret, O Cottingham, WN Foster, B Heath, GP Heath, HF McFall, JD Piccioni, D Scott, J Tapper, RJ Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Cartiglia, N Jing, Z Liu, W Mellado, B Parsons, JA Ritz, S Sacchi, R Sampson, S Sciulli, F Zhu, Q Chwastowski, J Eskreys, A Figiel, J Klimek, K Olkiewicz, K Przybycien, MB Stopa, P Zawiejski, L Adamczyk, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Bauerdick, LAT Behrens, U Bienlein, JK Burgard, C Desler, K Drews, G Fox-Murphy, A Fricke, U Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hasell, D Hebbel, K Johnson, KF Kasemann, M Koch, W Kotz, U Kowalski, H Lindemann, L Lohr, B Martinez, M Milewski, J Milite, M Monteiro, T Moritz, M Notz, D Pelucchi, F Piotrzkowski, K Rohde, M Saull, PRB Savin, AA Schneekloth, U Schwarzer, O Selonke, F Sievers, M Stonjek, S Tassi, E Wolf, G Wollmer, U Youngman, C Zeuner, W Burow, BD Coldewey, C Grabosch, HJ Viani, ALD Meyer, A Monig, K Schlenstedt, S Straub, PB Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Raach, H Wolfle, S Brook, NH Bussey, PJ Doyle, AT Lee, SW Macdonald, N McCance, GJ Saxon, DH Sinclair, LE Skillicorn, IO Strickland, E Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Garfagnini, A Gialas, I Gladilin, LK Kcira, D Klanner, R Lohrmann, E Poelz, G Zetsche, F Bacon, TC Cole, JE Howell, G Lamberti, L Long, KR Miller, DB Prinias, A Sedgbeer, JK Sideris, D Tapper, AD Walker, R Mallik, U Wang, SM Cloth, P Filges, D Ishii, T Kuze, M Suzuki, I Tokushuku, K Yamada, S Yamauchi, K Yamazaki, Y Ahn, SH An, SH Hong, SJ Lee, SB Nam, SW Park, SK Lim, H Park, IH Son, D Barreiro, F Fernandez, JP Garcia, G Glasman, C Hernandez, JM Labarga, L del Peso, J Puga, J Redondo, I Terron, J Corriveau, F Hanna, DS Hartmann, J Murray, WN Ochs, A Padhi, S Riveline, M Stairs, DG St-Laurent, M Wing, M Tsurugai, T Bashkirov, V Dolgoshein, BA Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Velthuis, JJ Verkerke, W Vossebeld, J Wiggers, L de Wolf, E Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Blaikley, HE Boogert, S Cashmore, RJ Cooper-Sarkar, AM Devenish, RCE Edmonds, JK Grosse-Knetter, J Harnew, N Matsushita, T Noyes, VA Quadt, A Ruske, O Sutton, MR Walczak, R Waters, DS Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dondana, S Dosselli, U Dusini, S Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Iannotti, L Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Raso, M Cormack, C Hart, JC McCubbin, NA Shah, TP Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Pavel, N Abramowicz, H Dagan, S Kananov, S Kreisel, A Levy, A Abe, T Fusayasu, T Inuzuka, M Nagano, K Umemori, K Yamashita, T Hamatsu, R Hirose, T Homma, K Kitamura, S Nishimura, T Arneodo, M Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Petrucci, MC Ruspa, M Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, D Butterworth, JM Catterall, CD Hayes, ME Heaphy, EA Jones, TW Lane, JB West, BJ Ciborowski, J Ciesielski, R Grzelak, G Nowak, RJ Pawlak, JM Pawlak, R Smalska, B Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Gadaj, T Deppe, O Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Foudas, C Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wildschek, T Wodarczyk, M Deshpande, A Dhawan, S Hughes, VW Bhadra, S Frisken, WR Hall-Wilton, R Khakzad, M Menary, S Schmidke, WB AF Breitweg, J Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Pellegrino, A Repond, J Stanek, R Yoshida, R Mattingly, MCK Abbiendi, G Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Coppola, N Corradi, M De Pasquale, S Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Eckert, M Hartmann, H Heinloth, K Hilger, E Jakob, HP Kappes, A Katz, UF Kerger, R Paul, E Rautenberg, J Schnurbusch, H Stifutkin, A Tandler, J Weber, A Wieber, H Bailey, DS Barret, O Cottingham, WN Foster, B Heath, GP Heath, HF McFall, JD Piccioni, D Scott, J Tapper, RJ Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Cartiglia, N Jing, Z Liu, W Mellado, B Parsons, JA Ritz, S Sacchi, R Sampson, S Sciulli, F Zhu, Q Chwastowski, J Eskreys, A Figiel, J Klimek, K Olkiewicz, K Przybycien, MB Stopa, P Zawiejski, L Adamczyk, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Bauerdick, LAT Behrens, U Bienlein, JK Burgard, C Desler, K Drews, G Fox-Murphy, A Fricke, U Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hasell, D Hebbel, K Johnson, KF Kasemann, M Koch, W Kotz, U Kowalski, H Lindemann, L Lohr, B Martinez, M Milewski, J Milite, M Monteiro, T Moritz, M Notz, D Pelucchi, F Piotrzkowski, K Rohde, M Saull, PRB Savin, AA Schneekloth, U Schwarzer, O Selonke, F Sievers, M Stonjek, S Tassi, E Wolf, G Wollmer, U Youngman, C Zeuner, W Burow, BD Coldewey, C Grabosch, HJ Viani, ALD Meyer, A Monig, K Schlenstedt, S Straub, PB Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Raach, H Wolfle, S Brook, NH Bussey, PJ Doyle, AT Lee, SW Macdonald, N McCance, GJ Saxon, DH Sinclair, LE Skillicorn, IO Strickland, E Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Garfagnini, A Gialas, I Gladilin, LK Kcira, D Klanner, R Lohrmann, E Poelz, G Zetsche, F Bacon, TC Cole, JE Howell, G Lamberti, L Long, KR Miller, DB Prinias, A Sedgbeer, JK Sideris, D Tapper, AD Walker, R Mallik, U Wang, SM Cloth, P Filges, D Ishii, T Kuze, M Suzuki, I Tokushuku, K Yamada, S Yamauchi, K Yamazaki, Y Ahn, SH An, SH Hong, SJ Lee, SB Nam, SW Park, SK Lim, H Park, IH Son, D Barreiro, F Fernandez, JP Garcia, G Glasman, C Hernandez, JM Labarga, L del Peso, J Puga, J Redondo, I Terron, J Corriveau, F Hanna, DS Hartmann, J Murray, WN Ochs, A Padhi, S Riveline, M Stairs, DG St-Laurent, M Wing, M Tsurugai, T Bashkirov, V Dolgoshein, BA Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Velthuis, JJ Verkerke, W Vossebeld, J Wiggers, L de Wolf, E Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Blaikley, HE Boogert, S Cashmore, RJ Cooper-Sarkar, AM Devenish, RCE Edmonds, JK Grosse-Knetter, J Harnew, N Matsushita, T Noyes, VA Quadt, A Ruske, O Sutton, MR Walczak, R Waters, DS Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dondana, S Dosselli, U Dusini, S Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Iannotti, L Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Raso, M Cormack, C Hart, JC McCubbin, NA Shah, TP Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Pavel, N Abramowicz, H Dagan, S Kananov, S Kreisel, A Levy, A Abe, T Fusayasu, T Inuzuka, M Nagano, K Umemori, K Yamashita, T Hamatsu, R Hirose, T Homma, K Kitamura, S Nishimura, T Arneodo, M Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Petrucci, MC Ruspa, M Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, D Butterworth, JM Catterall, CD Hayes, ME Heaphy, EA Jones, TW Lane, JB West, BJ Ciborowski, J Ciesielski, R Grzelak, G Nowak, RJ Pawlak, JM Pawlak, R Smalska, B Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Gadaj, T Deppe, O Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Foudas, C Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wildschek, T Wodarczyk, M Deshpande, A Dhawan, S Hughes, VW Bhadra, S Frisken, WR Hall-Wilton, R Khakzad, M Menary, S Schmidke, WB CA ZEUS Collaboration TI W production and the search for events with an isolated high-energy lepton and missing transverse momentum at HERA SO PHYSICS LETTERS B LA English DT Article ID CENTRAL TRACKING DETECTOR; ZEUS BARREL CALORIMETER; MONTE-CARLO GENERATOR; JET FRAGMENTATION; BOSON PRODUCTION; GAMMA COUPLINGS; E+E-PHYSICS; CONSTRUCTION; DESIGN; PROTON AB A search for the leptonic decays of W bosons produced in the reaction e(+)p --> e(+)W(+/-)X at a centre-of-mass energy of 300 GeV has been performed with the ZEUS detector at HERA using an integrated luminosity of 47.7 pb(-1). Three events consistent with W --> e nu decay are found, giving a cross section estimate of 0.9(-0.7)(+1.0) +/- 0.2 ph, in good agreement with the Standard Model prediction. The corresponding 95% C.L. upper limit on the cross section is 3.3 pb. A search for the decay W --> mu nu has a smaller selection efficiency and yields no candidate events. Limits on the cross section for W production with large hadronic transverse momentum have been obtained. A search for high-transverse-momentum isolated tracks in events with large missing transverse momentum yields results in good agreement with Standard Model expectations, in contrast to a recent report by the H1 collaboration of the observation of an excess of such events. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Andrews Univ, Berrien Springs, MI 49104 USA. Univ Bologna, Bologna, Italy. Ist Nazl Fis Nucl, I-40126 Bologna, Italy. Univ Bonn, Inst Phys, D-5300 Bonn, Germany. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Univ Calabria, Dept Phys, I-87036 Cosenza, Italy. Ist Nazl Fis Nucl, Cosenza, Italy. Chonnam Natl Univ, Kwangju, South Korea. Columbia Univ, Nevis Labs, Irvington, NY USA. Inst Nucl Phys, Krakow, Poland. Acad Min & Met, Fac Phys & Nucl Techniqes, Krakow, Poland. Jagiellonian Univ, Dept Phys, Krakow, Poland. DESY, Deutsch Elektronen Synchrotron, D-2000 Hamburg, Germany. DESY Zeuthen, Zeuthen, Germany. Univ Florence, Florence, Italy. Ist Nazl Fis Nucl, I-50125 Florence, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Freiburg, Fak Phys, D-7800 Freiburg, Germany. Univ Glasgow, Dept Phys & Astron, Glasgow, Lanark, Scotland. Univ Hamburg, Inst Expt Phys 1, Hamburg, Germany. Univ Hamburg, Inst Expt Phys 2, D-2000 Hamburg, Germany. Univ London Imperial Coll Sci Technol & Med, High Energy Nucl Phys Grp, London, England. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Forschungszentrum Julich, Inst Kernphys, Julich, Germany. Natl Lab High Energy Phys, KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki 305, Japan. Korea Univ, Seoul 136701, South Korea. Kyungpook Natl Univ, Taegu 702701, South Korea. Univ Autonoma Madrid, Dept Fis Teor, Madrid, Spain. McGill Univ, Dept Phys, Montreal, PQ, Canada. Meiji Gakuin Univ, Fac Gen Educ, Yokohama, Kanagawa, Japan. Moscow Engn Phys Inst, Moscow 115409, Russia. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow, Russia. NIKHEF H, Amsterdam, Netherlands. Univ Amsterdam, Amsterdam, Netherlands. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Oxford, Dept Phys, Oxford, England. Univ Padua, Dipartimento Fis, Padua, Italy. Ist Nazl Fis Nucl, Padua, Italy. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Polytechn Univ, Sagamihara, Kanagawa, Japan. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Rome, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Univ Siegen, Fachbereich Phys, D-5900 Siegen, Germany. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys, IL-69978 Tel Aviv, Israel. Univ Tokyo, Dept Phys, Tokyo 113, Japan. Tokyo Metropolitan Univ, Dept Phys, Tokyo, Japan. Univ Turin, Dipartimento Fis Sperimentale, Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Turin, Fac Sci 2, Turin, Italy. Ist Nazl Fis Nucl, Alessandria, Italy. Univ Toronto, Dept Phys, Toronto, ON, Canada. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT USA. York Univ, Dept Phys, Toronto, ON M3J 2R7, Canada. CNR, IROE, I-50127 Florence, Italy. DESY, Hamburg, Germany. Univ Piemonte Orientale, I-28100 Novara, Italy. UCL, Dept Phys & Astron, London, England. Warsaw Univ, Inst Phys Expt, Warsaw, Poland. Inst Nucl Studies, PL-00681 Warsaw, Poland. Weizmann Inst Sci, Dept Particle Phys, Rehovot, Israel. Univ Hamburg, Hamburg, Germany. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI dusini, stefano/J-3686-2012; Wing, Matthew/C-2169-2008; Bashkirov, Vladimir/A-4818-2008; Doyle, Anthony/C-5889-2009; De Pasquale, Salvatore/B-9165-2008; Golubkov, Yury/E-1643-2012; Proskuryakov, Alexander/J-6166-2012; Katz, Uli/E-1925-2013; Wiggers, Leo/B-5218-2015; Tassi, Enrico/K-3958-2015; Gladilin, Leonid/B-5226-2011; Morandin, Mauro/A-3308-2016; Solomin, Anatoly/C-3072-2016 OI dusini, stefano/0000-0002-1128-0664; Castellini, Guido/0000-0002-0177-0643; Doyle, Anthony/0000-0001-6322-6195; De Pasquale, Salvatore/0000-0001-9236-0748; Katz, Uli/0000-0002-7063-4418; Wiggers, Leo/0000-0003-1060-0520; Gladilin, Leonid/0000-0001-9422-8636; Morandin, Mauro/0000-0003-4708-4240; NR 36 TC 33 Z9 33 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD JAN 6 PY 2000 VL 471 IS 4 BP 411 EP 428 DI 10.1016/S0370-2693(99)01358-1 PG 18 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 277AD UT WOS:000084909800012 ER PT J AU Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GF Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, C James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B Magnin, J MayTal-Beck, S Meadows, B Neto, JRTD Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C AF Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GF Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, C James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B Magnin, J MayTal-Beck, S Meadows, B Neto, JRTD Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C CA E791 Collaboration TI Multidimensional resonance analysis of Lambda(+)(c) -> pK(-) pi(+) SO PHYSICS LETTERS B LA English DT Article DE multidimensional; resonance; Lambda(c); polarization ID C+ AB We present the results of a five-dimensional resonant amplitude analysis of the Lambda(c)(+) --> pK(-)pi(+) system based on 946 +/- 38 reconstructed decays. These data were produced in 500 GeV/c pi(-)-N interactions by Fermilab experiment E791. We report measurements of the amplitudes for Lambda(c)(+) decay into nonresonant pK(-)pi(+) and to p (K) over bar*(0)(890), Delta(++)(1232)K-, and Lambda(1520)pi(+) and we comment on other possible resonant enhancements. This is the first complete amplitude analysis of the Lambda(c)(+) --> pK(-)pi(+) system. We find that (54.8 +/- 5.5 +/- 3.5)% of the decays are nonresonant, (19.5 +/- 2.6 +/- 1.8)% of the decays are via the (K) over bar*(0) resonance, (18.0 +/- 2.9 +/- 2.9)% of the decays are via the Delta(++) resonance, and (7.7 +/- 1.8 +/- 1.1)% of the decays are via the Lambda(1520) resonance. We find evidence for an increasingly negative polarization of the Lambda(c)(+) baryons as a function of p(T)(2), in agreement with a recent model [W.G.D. Dharmaratna, G.R. Goldstein, Phys. Rev. D 53 (1996) 1073; G.R. Goldstein, hep-ph/9907573] and with a related measurement [M. Jezabek, K. Rybicki, R. Rylko, Phys. Lett. B 286 (1992) 175]. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Mississippi Oxford, University, MS 38677 USA. Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. CINVESTAV, Mexico City 07000, DF, Mexico. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. IIT, Chicago, IL 60616 USA. Kansas State Univ, Manhattan, KS 66506 USA. Univ Massachusetts, Amherst, MA 01003 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Autonoma Puebla, Puebla 72570, Mexico. Univ S Carolina, Columbia, SC 29208 USA. Stanford Univ, Stanford, CA 94305 USA. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Tufts Univ, Medford, MA 02155 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. RP Aitala, EM (reprint author), Univ Mississippi Oxford, University, MS 38677 USA. RI Anjos, Joao/C-8335-2013; Gobel Burlamaqui de Mello, Carla /H-4721-2016 OI Gobel Burlamaqui de Mello, Carla /0000-0003-0523-495X NR 18 TC 16 Z9 16 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 JAN 6 PY 2000 VL 471 IS 4 BP 449 EP 459 DI 10.1016/S0370-2693(99)01397-0 PG 11 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 277AD UT WOS:000084909800016 ER PT J AU Ettinger, JM AF Ettinger, JM TI A metric for positional games SO THEORETICAL COMPUTER SCIENCE LA English DT Article DE combinatorial games; Milnor games; Conway games AB We define an extended real-valued metric, rho, for positional games and prove that this class of games is a topological semigroup. We then show that two games are finitely separated iff they are path-connected and iff two closely related Conway games are equivalent. If two games are at a finite distance then this distance is bounded by the maximum difference of any two atoms found in the games. We may improve on this estimate when two games have the same form, as given by a form match. Finally, we show that if rho(G,H) = infinity then for all X we have G + X not equal H + X, a step towards proving cancellation for positional games. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ettinger, JM (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop B-230, Los Alamos, NM 87545 USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3975 J9 THEOR COMPUT SCI JI Theor. Comput. Sci. PD JAN 6 PY 2000 VL 230 IS 1-2 BP 207 EP 219 DI 10.1016/S0304-3975(99)00107-3 PG 13 WC Computer Science, Theory & Methods SC Computer Science GA 261MT UT WOS:000084013500011 ER PT J AU Ismagilov, ZR Kerzhentsev, MA Shkrabina, RA Tsikoza, LT Lunyushkin, BI Ostrovski, YV Kostin, AL Abroskin, IY Malyi, YN Matyukha, VA Adamson, MG Heywood, AC Zundelevich, Y Ismagilov, IZ Babko-Malyi, S Battleson, DM AF Ismagilov, ZR Kerzhentsev, MA Shkrabina, RA Tsikoza, LT Lunyushkin, BI Ostrovski, YV Kostin, AL Abroskin, IY Malyi, YN Matyukha, VA Adamson, MG Heywood, AC Zundelevich, Y Ismagilov, IZ Babko-Malyi, S Battleson, DM TI A role of catalysis for the destruction of waste from the nuclear industry SO CATALYSIS TODAY LA English DT Article; Proceedings Paper CT 2nd World Congress of Environmental Catalysis CY NOV 15-20, 1998 CL MIAMI, FLORIDA SP AIChE DE catalysis; catalysts; fluidized bed; mixed waste treatment; selective catalytic reduction of NOx; molten salts ID ION-EXCHANGED ZEOLITES; NITROGEN-OXIDES; SELECTIVE REDUCTION; FUEL COMBUSTION; DEEP OXIDATION; ORGANIC-COMPOUNDS; CARBON-MONOXIDE; CO-FERRIERITES; EXCESS OXYGEN; NITRIC-OXIDE AB Recent advances in application of catalysis to problems of waste destruction and off-gas treatment in the nuclear industry are presented: destruction of mixed organic wastes in a fluidized catalyst bed, mixed waste oxidation in catalytically active molten salts, selective catalytic reduction of NOx, in off-gases, catalytic oxidation of H-2 in the ventilation exhaust from liquid waste tanks and catalytic removal of VOCs in processes of groundwater and soil remediation. (C)2000 Elsevier Science B.V. All rights reserved. C1 Boreskov Inst Catalysis, Novosibirsk 630090, Russia. VNIPIET, Exploratory Design Inst, Novosibirsk 75, Russia. Novosibirsk Chem Concentrates Plant, Novosibirsk 630110, Russia. Siberian Chem Complex, Tomsk 636070, Russia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. MSE Technol Applicat Inc, Butte, MT 59702 USA. RP Ismagilov, ZR (reprint author), Boreskov Inst Catalysis, Lavrentiev Ave 5, Novosibirsk 630090, Russia. RI ismagilov, zinfer/L-9981-2013 OI ismagilov, zinfer/0000-0002-1520-9216 NR 103 TC 9 Z9 10 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 J9 CATAL TODAY JI Catal. Today PD JAN 5 PY 2000 VL 55 IS 1-2 BP 23 EP 43 DI 10.1016/S0920-5861(99)00223-0 PG 21 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 271XK UT WOS:000084620000004 ER PT J AU Choi, SM Wang, Y Nie, ZM Liu, J Peden, CHF AF Choi, SM Wang, Y Nie, ZM Liu, J Peden, CHF TI Cs-substituted tungstophosphoric acid salt supported on smesoporous silica SO CATALYSIS TODAY LA English DT Article; Proceedings Paper CT 2nd World Congress of Environmental Catalysis CY NOV 15-20, 1998 CL MIAMI, FLORIDA SP AIChE DE tungstophosphoric acid (TPA); heteropoly acid (HPA); mesoporous silica; Cs-TPA ID COMPRISING HETEROPOLY ACID; MOLECULAR-SIEVE; CATALYSTS; MCM-41; H3PW12O40 AB In this paper, we describe the characterization and catalytic properties of mesoporous silica supported Cs-substituted tungstophosphoric acid salt (Cs-TPA/MS) with improved dispersion of the active clusters compared to materials described previously in the literature. In particular, transmission electron micrographs and the activity results for a model alkylation reaction are presented as evidence for the enhanced dispersion and performance. In addition, we demonstrate improvements in the physical and thermal stability of these materials with Cs-substitution using various characterization techniques. (C)2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Choi, SM (reprint author), Pacific NW Lab, POB 999,MS K8-93, Richland, WA 99352 USA. RI Wang, Yong/C-2344-2013; OI Peden, Charles/0000-0001-6754-9928 NR 24 TC 76 Z9 77 U1 0 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 J9 CATAL TODAY JI Catal. Today PD JAN 5 PY 2000 VL 55 IS 1-2 BP 117 EP 124 DI 10.1016/S0920-5861(99)00231-X PG 8 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 271XK UT WOS:000084620000012 ER PT J AU Trettel, F Mantuano, E Calabresi, V Veneziano, L Olsen, AS Georgescu, A Gordon, L Sabbadini, G Frontali, M Jodice, C AF Trettel, F Mantuano, E Calabresi, V Veneziano, L Olsen, AS Georgescu, A Gordon, L Sabbadini, G Frontali, M Jodice, C TI A fine physical map of the CACNA1A gene region on 19p13.1-p13.2 chromosome SO GENE LA English DT Article DE EEF1D; HSPF1; polymorphic STR; PRKCA ID RADIATION HYBRID MAP; HUMAN GENOME; HUMAN DNA; FRAGMENTS; ATAXIA; CHANNEL; VECTOR AB The P/Q-type Ca2+ channel alpha(1A) subunit gene (CACNA1A) was cloned on the short arm of chromosome 19 between the markers D19S221 and D19S179 and found to be responsible for Episodic Ataxia type 2, Familial Hemiplegic Migraine and Spinocerebellar Ataxia type 6. This region was physically mapped by 11 cosmid contigs spanning about 1.4 Mb, corresponding to less than 70% of the whole region. The cosmid contig used to characterize the CACNA1A gene accounted only for the coding region of the gene lacking, therefore, the promoter and possible regulation regions. The present study improves the physical map around and within the CACNA1A by giving a complete cosmid or BAC contig coverage of the D19S221-D19S179 interval. A number of new STSs, whether polymorphic or not, were characterized and physically mapped within this region. Four ESTs were also assigned to cosmids belonging to specific contigs. (C) 2000 Elsevier Science B,V. All rights reserved. C1 Univ Roma Tor Vergata, Dipartimento Biol, I-00133 Rome, Italy. CNR, Ist Med Sperimentale, I-00137 Rome, Italy. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Jodice, C (reprint author), Univ Roma Tor Vergata, Dipartimento Biol, Via Ric Sci, I-00133 Rome, Italy. OI Mantuano, Elide/0000-0003-1656-5543; Veneziano, Liana/0000-0002-9921-8450; iodice, carla/0000-0002-1549-5005; trettel, flavia/0000-0002-7983-2955 FU Telethon [E.0847] NR 15 TC 13 Z9 14 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-1119 J9 GENE JI Gene PD JAN 4 PY 2000 VL 241 IS 1 BP 45 EP 50 DI 10.1016/S0378-1119(99)00470-9 PG 6 WC Genetics & Heredity SC Genetics & Heredity GA 278CX UT WOS:000084971300006 PM 10607897 ER PT J AU Laughlin, RB Pines, D AF Laughlin, RB Pines, D TI The theory of everything SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID BOSE-EINSTEIN CONDENSATION; RENORMALIZATION-GROUP; REDSHIFT SURVEY; ENERGIES; GAS AB We discuss recent developments in our understanding of matter, broadly construed, and their implications for contemporary research in fundamental physics. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Univ Calif, Off President, Inst Complex Adapt Matter, Oakland, CA 94607 USA. Univ Illinois, Sci & Technol Ctr Superconduct, Urbana, IL 61801 USA. Los Alamos Natl Lab, Neutron Sci Ctr Div, Los Alamos, NM 87545 USA. RP Laughlin, RB (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. NR 51 TC 236 Z9 241 U1 3 U2 40 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 JAN 4 PY 2000 VL 97 IS 1 BP 28 EP 31 DI 10.1073/pnas.97.1.28 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 271ZA UT WOS:000084624500008 PM 10618365 ER PT J AU Laughlin, RB Pines, D Schmalian, J Stojkovic, BP Wolynes, P AF Laughlin, RB Pines, D Schmalian, J Stojkovic, BP Wolynes, P TI The middle way SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID SPIN-GLASSES; ENERGY LANDSCAPES; ORDERED PHASE; TRANSITION; PROTEINS; SCIENCE; LIQUIDS; STATES AB Mesoscopic organization in soft, hard, and biological matter is examined in the context of our present understanding of the principles responsible for emergent organized behavior (crystallinity, ferromagnetism, superconductivity, etc.) at long wavelengths in very large aggregations of particles. Particular attention is paid to the possibility that as-yet-undiscovered organizing principles might be at work at the mesoscopic scale, intermediate between atomic and macroscopic dimensions, and the implications of their discovery for biology and the physical sciences. The search for the existence and universality of such rules, the proof or disproof of organizing principles appropriate to the mesoscopic domain, is called the middle way. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Univ Calif, Off President, Inst Complex Adapt Matter, Oakland, CA 94607 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Univ Illinois, Sci & Technol Ctr Superconductiv, Urbana, IL 61801 USA. Univ Illinois, Sch Chem Sci, Urbana, IL 61801 USA. RP Stojkovic, BP (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Schmalian, Joerg/H-2313-2011 NR 46 TC 142 Z9 146 U1 3 U2 25 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 JAN 4 PY 2000 VL 97 IS 1 BP 32 EP 37 DI 10.1073/pnas.97.1.32 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 271ZA UT WOS:000084624500009 PM 10618366 ER PT J AU Sutherland, BM Bennett, PV Sidorkina, O Laval, J AF Sutherland, BM Bennett, PV Sidorkina, O Laval, J TI Clustered DNA damages induced in isolated DNA and in human cells by low doses of ionizing radiation SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID COLI ENDONUCLEASE-III; DOUBLE-STRAND BREAKS; HUMAN APURINIC/APYRIMIDINIC ENDONUCLEASE; INDUCED SINGLE-STRAND; ESCHERICHIA-COLI; GEL-ELECTROPHORESIS; SUBSTRATE-SPECIFICITY; ABASIC SITES; EXONUCLEASE-III; MAMMALIAN-CELLS AB Clustered DNA damages-two or more closely spaced damages (strand breaks, abasic sites, or oxidized bases) on opposing strands-are suspects as critical lesions producing lethal and mutagenic effects of ionizing radiation, However, as a result of the lack of methods for measuring damage clusters induced by ionizing radiation in genomic DNA, neither the frequencies of their production by physiological doses of radiation, nor their repairability, nor their biological effects are known. On the basis of methods that we developed for quantitating damages in large DNAs, we have devised and validated a way of measuring ionizing radiation-induced clustered lesions in genomic DNA, including DNA from human cells. DNA is treated with an endonuclease that induces a single-strand cleavage at an oxidized base or abasic site. If there are two closely spaced damages on opposing strands, such cleavage will reduce the size of the DNA on a nondenaturing gel. We show that ionizing radiation does induce clustered DNA damages containing abasic sites, oxidized purines, or oxidized pyrimidines. Further, the frequency of each of these cluster classes is comparable to that of frank double-strand breaks; among all complex damages induced by ionizing radiation, double-strand breaks are only about 20%, with other clustered damage constituting some 80%. We also show that even low doses (0.1-1 Gy) of high linear energy transfer ionizing radiation induce clustered damages in human cells. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Inst Gustave Roussy, CNRS, UMR 1772, Grp Reparat ADN, F-94805 Villejuif, France. RP Sutherland, BM (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 51 TC 315 Z9 323 U1 1 U2 15 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 JAN 4 PY 2000 VL 97 IS 1 BP 103 EP 108 DI 10.1073/pnas.97.1.103 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 271ZA UT WOS:000084624500021 PM 10618378 ER PT J AU Cui, Y Bustamante, C AF Cui, Y Bustamante, C TI Pulling a single chromatin fiber reveals the forces that maintain its higher-order structure SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID NUCLEOSOME CORE PARTICLE; CRYOELECTRON MICROSCOPY; LINKER HISTONES; DNA-MOLECULES; RESOLUTION; ELASTICITY; COMPACTION; DYNAMICS; TITIN; TENSION AB Single chicken erythrocyte chromatin fibers were stretched and released at room temperature with force-measuring laser tweezers. In low ionic strength, the stretch-release curves reveal a process of continuous deformation with little or no internucleosomal attraction. A persistence length of 30 nm and a stretch modulus of approximate to 5 pN is determined for the fibers. At forces of 20 pN and higher, the fibers are modified irreversibly, probably through the mechanical removal of the histone cores from native chromatin. In 40-150 mM NaCl, a distinctive condensation-decondensation transition appears between 5 and 6 pN. corresponding to an internucleosomal attraction energy of approximate to 2.0 kcal/mol per nucleosome. Thus, in physiological ionic strength the fibers possess a dynamic structure in which the fiber locally interconverting between "open" and "closed" states because of thermal fluctuations. C1 Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Bustamante, C (reprint author), Univ Calif Berkeley, Dept Mol & Cell Biol, 229 Stanley Hall, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [GM-32543, R01 GM032543, R37 GM032543] NR 35 TC 283 Z9 287 U1 3 U2 27 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 JAN 4 PY 2000 VL 97 IS 1 BP 127 EP 132 DI 10.1073/pnas.97.1.127 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 271ZA UT WOS:000084624500025 PM 10618382 ER PT J AU Yang, GL Cecconi, C Baase, WA Vetter, IR Breyer, WA Haack, JA Matthews, BW Dahlquist, FW Bustamante, C AF Yang, GL Cecconi, C Baase, WA Vetter, IR Breyer, WA Haack, JA Matthews, BW Dahlquist, FW Bustamante, C TI Solid-state synthesis and mechanical unfolding of polymers of T4 lysozyme SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID ELASTICITY; MOLECULES; TITIN; DNA; MUTANTS AB Recent advances in single molecule manipulation methods offer a novel approach to investigating the protein folding problem. These studies usually are done on molecules that are naturally organized as linear arrays of globular domains. To extend these techniques to study proteins that normally exist as monomers, we have developed a method of synthesizing polymers of protein molecules in the solid state. By introducing cysteines at locations where bacteriophage T4 lysozyme molecules contact each other in a crystal and taking advantage of the alignment provided by the lattice, we have obtained polymers of defined polarity up to 25 molecules long that retain enzymatic activity. These polymers then were manipulated mechanically by using a modified scanning force microscope to characterize the force-induced reversible unfolding of the individual lysozyme molecules. This approach should be general and adaptable to many other proteins with known crystal structures. For T4 lysozyme, the force required to unfold the monomers was 64 +/- 16 pN at the pulling speed used. Refolding occurred within 1 sec of relaxation with an efficiency close to 100%. Analysis of the force versus extension curves suggests that the mechanical unfolding transition follows a two-state model. The unfolding forces determined in 1 M guanidine hydrochloride indicate that in these conditions the activation barrier for unfolding is reduced by 2 kcal/mol. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Oregon, Inst Mol Biol, Eugene, OR 97403 USA. Univ Oregon, Dept Chem, Eugene, OR 97403 USA. Max Planck Inst Mol Physiol, Dept Biol Struct, D-44227 Dortmund, Germany. Nutri Log Inc, Portland, OR 97201 USA. Univ Oregon, Howard Hughes Med Inst, Eugene, OR 97403 USA. RP Bustamante, C (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Cecconi, Ciro/K-5028-2016 OI Cecconi, Ciro/0000-0002-6101-2609 FU NIGMS NIH HHS [GM-21967, GM-32543, GM-57766, R01 GM021967, R01 GM032543, R01 GM057766, R37 GM032543, T32 GM007759] NR 18 TC 171 Z9 174 U1 2 U2 14 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 JAN 4 PY 2000 VL 97 IS 1 BP 139 EP 144 DI 10.1073/pnas.97.1.139 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 271ZA UT WOS:000084624500027 PM 10618384 ER PT J AU Anders, A AF Anders, A TI Breakdown of the high-voltage sheath in metal plasma immersion ion implantation SO APPLIED PHYSICS LETTERS LA English DT Article ID SURFACE MODIFICATION; VACUUM ARCS AB It is suggested that breakdown of a space-charge sheath obeys similar breakdown laws as known for vacuum breakdown. When metal plasmas of vacuum arcs are used, the sheath between a biased substrate and plasma is very thin and the electric-field strength is very high. Field enhancement (e.g., at sharp edges of the substrate) leads to thermal instability of electron emission centers, followed by dense plasma formation which, in turn, electrically short circuits the sheath (breakdown). Theoretical and experimental evidence for this mechanism is presented. (C) 2000 American Institute of Physics. [S0003-6951(00)02301-9]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Anders, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Anders, Andre/B-8580-2009 OI Anders, Andre/0000-0002-5313-6505 NR 15 TC 21 Z9 22 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 3 PY 2000 VL 76 IS 1 BP 28 EP 30 DI 10.1063/1.125645 PG 3 WC Physics, Applied SC Physics GA 269YR UT WOS:000084505600010 ER PT J AU Mao, SS Mao, XL Greif, R Russo, RE AF Mao, SS Mao, XL Greif, R Russo, RE TI Dynamics of an air breakdown plasma on a solid surface during picosecond laser ablation SO APPLIED PHYSICS LETTERS LA English DT Article AB Using picosecond time-resolved shadowgrams and interferograms, we measured the lateral expansion of an early stage ablation plasma induced by a 1064 nm, 35 ps laser pulse on a copper target. The plasma was found to have an electron density on the order of 10(20) cm(-3) near the target surface. Prior to the expanding material vapor plume, this high density plasma originates from the breakdown of air, assisted by laser-induced electron emission from the target surface. The longitudinal expansion of the plasma was suppressed due to the development of a strong space-charge region. At postpulse times, the relation r similar to t(1/2) was found for the temporal lateral expansion of the radius of the plasma. Measurements of energy absorption by the plasma provide an interpretation for the experimentally measured reduction in ablation efficiency as the laser fluence increases beyond approximately 100 J/cm(2). (C) 2000 American Institute of Physics. [S0003-6951(00)01801-5]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Russo, RE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 8 TC 34 Z9 35 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 3 PY 2000 VL 76 IS 1 BP 31 EP 33 DI 10.1063/1.125646 PG 3 WC Physics, Applied SC Physics GA 269YR UT WOS:000084505600011 ER PT J AU Bardakci, K AF Bardakci, K TI An operator approach to string equations SO NUCLEAR PHYSICS B LA English DT Article DE string threory; operator approach; Virasoro algebra ID GENERALIZED SIGMA-MODEL; FIELD-THEORY; INVARIANCE; SPACE AB In this paper, a new approach to string dynamics is proposed. String coordinates are identified with a non-commuting set of operators familiar from free string quantization, and the dynamics follows from the Virasoro algebra. Then is a very large gauge group operating on the non-commuting coordinates. The gauge has to be fixed suitably to make contact with the standard string picture. (C) 2000 Elsevier Science B.V. All lights reserved. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Bardakci, K (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 36 TC 0 Z9 0 U1 0 U2 0 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 JAN 3 PY 2000 VL 564 IS 1-2 BP 285 EP 299 DI 10.1016/S0550-3213(99)00556-8 PG 15 WC Physics, Particles & Fields SC Physics GA 268BE UT WOS:000084393800015 ER PT J AU Briere, RA Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M von Dombrowski, S Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, E Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H Spencer, MB von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Wolf, A Wu, J Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, TK Richman, JD Roberts, D AF Briere, RA Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M von Dombrowski, S Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, E Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H Spencer, MB von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Wolf, A Wu, J Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, TK Richman, JD Roberts, D CA CLEO Collaboration TI Search for rare and forbidden eta ' decays SO PHYSICAL REVIEW LETTERS LA English DT Article AB We have searched for rare and forbidden decays of the eta' meson in hadronic events at the CLEO II detector. The search is conducted on 4.80 fb(-1) of e(+)e(-) collisions at 10.6 GeV center-of-mass energy at the Cornell Electron Storage Ring. We find no signals, and set 90% confidence level upper limits of their branching fractions: B(eta' --> e(+)e(-)eta) < 2.4 x 10(-3), B(eta' --> e(+)e(-) pi(0)) < 1.4 x 10(-3), B(eta' --> e(+)e(-) gamma) < 0.9 x 10(-3), and B(eta' --> e mu) < 4.7 x 10(-4). We also fit the matrix element of the eta' --> pi(+)pi(-) eta Dalitz plot with the parametrization \M\(2) = A\1 + alpha gamma\(2), where gamma is a linear function of the kinetic energy of the eta, and find Re(alpha) =-0.021 +/- 0.025. C1 Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Ottawa, ON, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Yonsei Univ, Seoul 120749, South Korea. Univ Cincinnati, Cincinnati, OH 45221 USA. RP Briere, RA (reprint author), Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014 OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039 NR 9 TC 20 Z9 21 U1 2 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 JAN 3 PY 2000 VL 84 IS 1 BP 26 EP 30 DI 10.1103/PhysRevLett.84.26 PG 5 WC Physics, Multidisciplinary SC Physics GA 271HJ UT WOS:000084587900007 ER PT J AU Lindenberg, AM Kang, I Johnson, SL Missalla, T Heimann, PA Chang, Z Larsson, J Bucksbaum, PH Kapteyn, HC Padmore, HA Lee, RW Wark, JS Falcone, RW AF Lindenberg, AM Kang, I Johnson, SL Missalla, T Heimann, PA Chang, Z Larsson, J Bucksbaum, PH Kapteyn, HC Padmore, HA Lee, RW Wark, JS Falcone, RW TI Time-resolved X-ray diffraction from coherent phonons during a laser-induced phase transition SO PHYSICAL REVIEW LETTERS LA English DT Article ID STREAK-CAMERA; GENERATION; PULSES AB Time-resolved x-ray diffraction with picosecond temporal resolution is used to observe scattering from impulsively generated coherent acoustic phonons in laser-excited InSb crystals. The observed frequencies and damping rates are in agreement with a model based on dynamical diffraction theory coupled to analytic solutions for the laser-induced strain profile. The results are consistent with a 12 ps thermal electron-acoustic phonon coupling time together with an instantaneous component from the deformation-potential interaction. Above a critical laser fluence, we show that the first step in the transition to a disordered state is the excitation of large amplitude, coherent atomic motion. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Michigan, Ctr Ultrafast Opt Sci, Ann Arbor, MI 48109 USA. Lund Inst Technol, Atom Phys Div, Lund, Sweden. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. RP Lindenberg, AM (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Johnson, Steven/B-3252-2008; Chang, Zenghu/K-8143-2012; Kapteyn, Henry/H-6559-2011 OI Johnson, Steven/0000-0001-6074-4894; Chang, Zenghu/0000-0001-9015-0747; Kapteyn, Henry/0000-0001-8386-6317 NR 22 TC 271 Z9 276 U1 3 U2 53 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 JAN 3 PY 2000 VL 84 IS 1 BP 111 EP 114 DI 10.1103/PhysRevLett.84.111 PG 4 WC Physics, Multidisciplinary SC Physics GA 271HJ UT WOS:000084587900028 ER PT B AU Coke, LR Sanchez, JG Policastro, AJ AF Coke, LR Sanchez, JG Policastro, AJ BE Caserta, AS TI A model for the dispersion of contaminants in the subway environment SO 10TH INTERNATIONAL SYMPOSIUM ON AERODYNAMICS AND VENTILATION OF VEHICLE TUNNELS: PRINCIPLES, ANALYSIS AND DESIGN SE BHR GROUP CONFERENCE SERIES PUBLICATION LA English DT Proceedings Paper CT 10th International Symposium on Aerodynamics and Ventilation of Vehicle Tunnels CY NOV 01-03, 2000 CL BOSTON, MA SP BHR Grp Ltd, Parsons Brinckerhoff Quade & Douglas Inc, Amer Warming & Ventilating, Kaiser Engineers Inc, Natl Fire Protect Assoc, Ventilaotren Sirocco Howden BV AB Although subway ventilation has been studied extensively, very little has been published on dispersion of contaminants in the subway environment. This paper presents a model that predicts dispersion of contaminants in a complex subway system. It accounts for the combined transient effects of train motion, station airflows, train car air exchange rates and source release properties. Results are presented for a range of typical subway scenarios. The effects of train piston action and train car air exchange are discussed. The model could also be applied to analyse the environmental impact of hazardous materials releases such as chemical and biological agents. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Coke, LR (reprint author), Argonne Natl Lab, Argonne, IL 60439 USA. NR 17 TC 1 Z9 1 U1 0 U2 1 PU PROFESSIONAL ENGINEERING PUBLISHING LTD PI WESTMINISTER PA 1 BIRDCAGE WALK, WESTMINISTER SW1H 9JJ, ENGLAND BN 1-86058-255-9 J9 BHR GR CONF SER PUBL PY 2000 IS 43 BP 279 EP 303 PG 25 WC Engineering, Civil; Transportation Science & Technology SC Engineering; Transportation GA BR37F UT WOS:000166217000017 ER PT B AU Shoshani, A Sim, A Bernardo, LM Nordberg, H AF Shoshani, A Sim, A Bernardo, LM Nordberg, H BE Gunther, O Lenz, HJ TI Coordinating simultaneous caching of file bundles from tertiary storage SO 12TH INTERNATIONAL CONFERENCE ON SCIENTIFIC AND STATISTICAL DATABASE MANAGEMENT, PROCEEDINGS LA English DT Proceedings Paper CT 12th International Conference on Scientific and Statistical Database Management CY JUL 26-28, 2000 CL BERLIN, GERMANY SP Deutsch Forsch Gemeinschaft, Freie Univ Berlin, Humboldt Univ Berlin, MicroStrategy Deutschland, SAS Inst Deutschland, Scopeland, Stat Landesamt Berlin AB In a previous paper [Shoshani et al 99], we described a system called STAGS (Storage Access Coordination System) for High Energy and Physics (HEP) experiments. These experiments generate very large volumes of "event" data at a very high rate. The volumes of data may reach 100 's of terabytes/year and therefore they are stored on robotic tape systems that are managed by a mass storage system. The data are stored as fries on tapes according to a predetermined order, usually according to the order they are generated. A major bottleneck is the retrieval of subsets of these large datasets during the analysis phase. STAGS is designed to optimize the use of a disk cache, and thus minimize the number of files read from tape. In this paper, we describe an interesting problem of disk staging coordination that goes beyond the one-file-at-a-time requirement. The problem stems from the need to coordinate the simultaneous caching of groups of fries that we refer to as "bundles of files". All files from a bundle need to be at the same time in the disk cache in order for the analysis application to proceed. This is a radically different problem from the case where the analysis applications need only one file at a time. In this paper, we describe the method of identifying the file bundles, and the scheduling of bundle caching in such a way that fries shared between bundles are not removed from the cache unnecessarily. We describe the methodology and the policies used to determine the order of caching bundles of files, and the order of removing fries from the cache when space is needed. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Div, Berkeley, CA 94720 USA. RP Shoshani, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Div, Berkeley, CA 94720 USA. NR 3 TC 6 Z9 7 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0686-0 PY 2000 BP 196 EP 206 DI 10.1109/SSDM.2000.869788 PG 11 WC Computer Science, Information Systems SC Computer Science GA BR05V UT WOS:000165528300015 ER PT S AU Istrate, G AF Istrate, G GP IEEE IEEE TI Computational complexity and phase transitions SO 15TH ANNUAL IEEE CONFERENCE ON COMPUTATIONAL COMPLEXITY, PROCEEDINGS SE ANNUAL IEEE CONFERENCE ON COMPUTATIONAL COMPLEXITY LA English DT Proceedings Paper CT 15th Annual IEEE Conference on Computational Complexity CY JUL 04-07, 2000 CL FLORENCE, ITALY SP IEEE Comp Soc, Tech Comm Math Fdn Comp, ACM SIGACT, EATCS AB Phase transitions in combinatorial problems have recently been shown [2] to be useful in locating "hard" instances of combinatorial problems. The connection between computational complexity and the existence of phase transitions has been addressed in Statistical Mechanics [2] and Artificial Intelligence [3], but not studied rigorously We take a first step in this direction by investigating the existence of sharp thresholds for the class of generalized satisfiability problems, defined by Schaefer [4]. In the case when ail constraints have a special clausal form we completely characterize the generalized satisfiability problems that have a sharp threshold. While NP-completeness does not imply the sharpness of the threshold, our result suggests that the class of counterexamples is rather limited, as ail such counterexamples can be predicted, with constant success probability by a single procedure. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Istrate, G (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Mail Stop B258, Los Alamos, NM 87545 USA. NR 14 TC 4 Z9 4 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1093-0159 BN 0-7695-0674-7 J9 ANN IEEE CONF COMPUT PY 2000 BP 104 EP 115 DI 10.1109/CCC.2000.856740 PG 12 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BQ67E UT WOS:000089141500011 ER PT B AU Costigan, KR Bossert, JE Langley, DL AF Costigan, KR Bossert, JE Langley, DL GP AMS AMS TI Simulations of precipitation over the upper Rio Grande Basin SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Costigan, KR (reprint author), Univ Calif Los Alamos Natl Lab, EES-8 Mailstop D401, Los Alamos, NM 87545 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 40 EP 42 PG 3 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100012 ER PT B AU Stalker, JR Bossert, JE Costigan, KR Reisner, JM Langley, DL AF Stalker, JR Bossert, JE Costigan, KR Reisner, JM Langley, DL GP AMS AMS TI Use of cumulus parameterization and explicit microphysics for climate studies over the Rio Grande basin SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID MODELS; SCALE; PREDICTION; CONVECTION; SIMULATION; SYSTEMS; RELEASE; CLOSURE; SCHEME; RAMS C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663,EES-8,Mail Stop D401, Los Alamos, NM 87545 USA. NR 24 TC 2 Z9 2 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 74 EP 79 PG 6 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100023 ER PT B AU Leung, LR Wigmosta, MS AF Leung, LR Wigmosta, MS GP AMS AMS TI The roles of subgrid topography on land-atmosphere interactions SO 15TH CONFERENCE ON HYDROLOGY LA English DT Proceedings Paper CT 15th Conference on Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID OROGRAPHIC PRECIPITATION; SURFACE HYDROLOGY; TERRAIN; MODEL C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Leung, LR (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, POB 999, Richland, WA 99352 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 194 EP 197 PG 4 WC Meteorology & Atmospheric Sciences; Water Resources SC Meteorology & Atmospheric Sciences; Water Resources GA BS07R UT WOS:000168561100056 ER PT S AU Yang, Q Parvin, B Mariano, A AF Yang, Q Parvin, B Mariano, A BE Sanfeliu, A Villanueva, JJ Vanrell, M Alquezar, R Eklundh, JO Aloimonos, Y TI Singular features in sea surface temperature data SO 15TH INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION, VOL 1, PROCEEDINGS: COMPUTER VISION AND IMAGE ANALYSIS SE INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION LA English DT Proceedings Paper CT 15th International Conference on Pattern Recognition (ICPR-2000) CY SEP 03-07, 2000 CL BARCELONA, SPAIN SP Int Assoc Pattern Recognit, Assoc Pattern Recognit & Image Anal, Ctr Visio Comp, Univ Autonoma Barcelona, Univ Politecn Catalunya, Comissionat Universitats Recerca, Generalitat Catalunya Dept Presidencia, Minist Ciencia Tecnol, Fdn Catalana Recerca, HP Invent AB We propose to detect singular features in order to generate an intelligent summary of high resolution spatiotemporal data that are obtained from satellite-based observations of the ocean. Toward this objective, we extend the Horn-Schunck model of flow field computation to incorporate incompressibility for tracking fluid motion. This is expressed as a zero-divergence constraint in the variational problem and an efficient multigrid implementation of it is introduced. Additionally, we show an effective localization of event features, such as vortices and saddle points, in the velocity field that can be used for subsequent abstraction, query and statistical analysis. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Yang, Q (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1051-4651 BN 0-7695-0751-4 J9 INT C PATT RECOG PY 2000 BP 516 EP 520 PG 5 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BR56N UT WOS:000166814700111 ER PT S AU Cong, G Parvin, B AF Cong, G Parvin, B BE Sanfeliu, A Villanueva, JJ Vanrell, M Alquezar, R Crowley, J Shirai, Y TI Surface recovery from planar sectional contours SO 15TH INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION, VOL 4, PROCEEDINGS: APPLICATIONS, ROBOTICS SYSTEMS AND ARCHITECTURES SE INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION LA English DT Proceedings Paper CT 15th International Conference on Pattern Recognition (ICPR-2000) CY SEP 03-07, 2000 CL BARCELONA, SPAIN SP Int Assoc Pattern Recognit, Assoc Pattern Recognit & Image Anal, Ctr Visio Comp, Univ Autonoma Barcelona, Univ Politecn Catalunya, Comissionat Universitats Recerca, Generalitat Catalunya Dept Presidencia, Minist Ciencia Tecnol, Fdn Catalana Recerca, HP Invent ID CROSS-SECTIONS; SHAPE RECONSTRUCTION; TRIANGULATION; ALGORITHM AB In this paper, we propose a new approach for surface recovery from planar sectional contours. The surface is reconstructed based on the so-called "Equal Importance Criterion," which suggests that every point in the region contributes equally to the reconstruction process. The problem is then formulated in terms of a partial differeXntial equation, and the solution is efficiently calculated from distance transformation. To make the algorithm valid for different application purposes, both the isosurface and the primitive representations of the object surface are derived. The isosurface is constructed by PDE (Partial Differential Equation), which can be solved iteratively. The traditional distance interpolating method, which was used by several researchers for surface reconstruction, is an approximate solution of the PDE. The primitive representations are approximated by Voronoi Diagram transformation of the surface space. Isosurfaces have the advantage that subsequent geometric analysis of the object can be easily carried out while primitive representation is easy to visualize. The proposed technique allows for surface recovery at any desired resolution, thus avoiding the inherent problems of correspondence, tiling, and branching. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Cong, G (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 37 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1051-4651 BN 0-7695-0751-4 J9 INT C PATT RECOG PY 2000 BP 106 EP 109 PG 4 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BR56Q UT WOS:000166815200023 ER PT B AU Hummel, JR Campbell, AP Kehrer, ML Lurie, GR Simunich, KL AF Hummel, JR Campbell, AP Kehrer, ML Lurie, GR Simunich, KL GP AMS AMS TI The incorporation of high resolution climatological data into environmental tactical decision aids SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Argonne Natl Lab, Decis & Informat Sci Lab, Argonne, IL 60439 USA. RP Hummel, JR (reprint author), Argonne Natl Lab, Decis & Informat Sci Lab, 9700 S Cass Ave,DIS-900, Argonne, IL 60439 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 46 EP 49 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800014 ER PT B AU Parker, MJ Hunter, CH Heavner, LC Snyder, GL Mueller, RA AF Parker, MJ Hunter, CH Heavner, LC Snyder, GL Mueller, RA GP AMS AMS TI An integrated meteorological monitoring and display system for emergency response SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Parker, MJ (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Bldg 735-7A, Aiken, SC 29808 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 178 EP 178 PG 1 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800054 ER PT B AU Yang, Q Parvin, B AF Yang, Q Parvin, B GP AMS AMS TI Detection and tracking of vortices and saddle points from SST data SO 16TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY AND HYDROLOGY LA English DT Proceedings Paper CT 16th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology CY JAN 09-14, 2000 CL LONG BEACH, CA SP Amer Meteorol Soc ID FLOW AB We extend the Horn-Schunck model of flow field computation to incorporate incompressibility for tracking fluid motion. This is expressed as a zero-divergence constraint in the variational problem and implemented with a mutigrid approach for efficient computation. Additionally, we show effective detection and tracking of singular events, such as vortices and saddle points, from the velocity field. We have applied our approach to 12 years of AVHRR data at 18 Km resolution and tabulated a feature database for data mining. Our analysis indicates preferred localization of singular events over long time scales. C1 Lawrence Berkeley Natl Lab, Div Informat & Comp Sci, Berkeley, CA 94720 USA. RP Yang, Q (reprint author), Lawrence Berkeley Natl Lab, Div Informat & Comp Sci, Berkeley, CA 94720 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 464 EP 467 PG 4 WC Computer Science, Interdisciplinary Applications; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing SC Computer Science; Meteorology & Atmospheric Sciences; Oceanography; Remote Sensing GA BS03Y UT WOS:000168410800139 ER PT S AU Sigmon, TW Toet, D Carey, PG Smith, PM Wickboldt, P AF Sigmon, TW Toet, D Carey, PG Smith, PM Wickboldt, P BE Miyamoto, I Sugioka, K Sigmon, TW TI Applications of pulsed lasers in low temperature thin film electronics fabrication SO 1ST INTERNATIONAL SYMPOSIUM ON LASER PRECISION MICROFABRICATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1st International Symposium on Laser Precision Microfabrication CY JUN 14-16, 2000 CL OMIYA, JAPAN SP Japan Laser Processing Soc, Inst Phys & Chem Res, SPIE, USAF, Off Sci Res, Asian Off Aerosp Res & Dev, Saitama Fdn Culture & Ind, High Temp Soc Japan, Japan Soc Appl Phys, Japan Soc Precis Engn, Japan Welding Engn Soc, Japan Welding Soc, Laser Soc Japan, Osaka Univ, Collaborat Res Ctr Adv Sci & Technol ID AMORPHOUS-SILICON; TRANSISTORS; TFTS AB For the past several years, our group has focused on the development of polysilicon thin film transistor (TFT) processes having maximum allowable substrate temperatures between 100 degrees to 350 degreesC. These processes are based on excimer laser crystallization of low temperature deposited a-Si thin films combined with low temperature deposited dielectrics and self-aligned gate TFT structures. We have also developed a laser-based, source-drain-gate doping/annealing process. Typical n-channel TFT mobilities found are mu (n) similar to 150 cm(2)/V-s for the 100 degrees CC process and similar to 400 cm(2)/V-s for the 350 degreesC process. In this paper we describe the basic processes and process physics. We then show results for TFTs fabricated at a variety of maximum substrate temperatures and a-Si deposition techniques. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Sigmon, TW (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-395, Livermore, CA 94550 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3731-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4088 BP 73 EP 79 DI 10.1117/12.405690 PG 7 WC Engineering, Manufacturing; Materials Science, Multidisciplinary; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BR57D UT WOS:000166833700014 ER PT B AU Gai, W AF Gai, W BE Liu, S Shen, X TI High power RF generation by relativistic beams in dielectric structures and its application to the advanced accelerators SO 2000 25TH INTERNATIONAL CONFERENCE ON INFRARED AND MILLIMETER WAVES CONFERENCE DIGEST LA English DT Proceedings Paper CT 25th International Conference on Infrared and Millimeter Waves CY SEP 12-15, 2000 CL BEIJING, PEOPLES R CHINA SP Natl Sci Fdn China, Chinese Inst Electr, Univ Electr Sci & Technol China, IEEE MTT ID WAKE-FIELD AB We have studied the interaction of a high current relativistic electron beam with dielectric loaded waveguides as a source of high power electromagnetic radiation. A unique high current photoinjector-based electron linac was used to generate the drive beam for these experiments. Travelling wave dielectric structures with luminal (v(phase) = c) frequencies of 7.8, 15 and 20 GHz were used. The rf power levels generated in these experiments were very large- up to 4 - 20 MW. This class of RF sources has been used for two beam acceleration studies for future linear collider research. With the newly improved RF photoinjector at the Argonne National Laboratory (ANL), we expect to generate up to 0.5 GW RF power in the range of 20 - 60 GHz with a pulse length of tens ns. With this soon to be available RF power source, we could test acceleration structures up to gradients of 1 GV/m. C1 Argonne Natl Lab, High Energy Phys Div, Argonne, IL 60439 USA. RP Gai, W (reprint author), Argonne Natl Lab, High Energy Phys Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6513-5 PY 2000 BP 261 EP 262 DI 10.1109/ICIMW.2000.893023 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR44B UT WOS:000166423000113 ER PT B AU Park, HK Deng, B Domier, CW Lee, KC Luhmann, NC AF Park, HK Deng, B Domier, CW Lee, KC Luhmann, NC BE Liu, S Shen, X TI Status of Far Infrared Tangential Interferometry/Polarimetry (FIReTIP) on NSTX SO 2000 25TH INTERNATIONAL CONFERENCE ON INFRARED AND MILLIMETER WAVES CONFERENCE DIGEST LA English DT Proceedings Paper CT 25th International Conference on Infrared and Millimeter Waves CY SEP 12-15, 2000 CL BEIJING, PEOPLES R CHINA SP Natl Sci Fdn China, Chinese Inst Electr, Univ Electr Sci & Technol China, IEEE MTT ID MULTICHANNEL AB The Influence of paramagnetism and-diamagnetism will significantly alter the vacuum toroidal magnetic field in spherical torus. Therefore, plasma parameters dependent upon BT such as the q-profile and local beta value needs an independent measurement of B-r(r,t) The multi-chord Tangential Far infrared Interferometer/ Polarimeter (FIReTIP) system [1] currently under development for National Spherical Torus Experiment (NSTX) will provide temporally and radially resolved toroidal field profile [B-r(r,t)3 and 2-D electron density profile [n(e)(r,t)] data. Two channel interferometer will be operational this year and full system will be ready by 2002. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Park, HK (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6513-5 PY 2000 BP 431 EP 432 DI 10.1109/ICIMW.2000.893094 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR44B UT WOS:000166423000183 ER PT B AU Nassiri, A Kang, YW Song, JJ AF Nassiri, A Kang, YW Song, JJ BE Liu, S Shen, X TI Millimeter-wave structures and drivers for future linear colliders SO 2000 25TH INTERNATIONAL CONFERENCE ON INFRARED AND MILLIMETER WAVES CONFERENCE DIGEST LA English DT Proceedings Paper CT 25th International Conference on Infrared and Millimeter Waves CY SEP 12-15, 2000 CL BEIJING, PEOPLES R CHINA SP Natl Sci Fdn China, Chinese Inst Electr, Univ Electr Sci & Technol China, IEEE MTT AB There is a growing interest in the development of very high gradient (greater than or equal to 1 GeV/meter) accelerating structures and millimeter-wave power sources. The need for very high gradient structures to be operated in W-band or at higher frequencies poses great technical challenges and demands innovation in rf science and technology to reach this goal. Requirements for microstructure fabrication and power sources based on deep x-ray lithography techniques are examined. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Nassiri, A (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6513-5 PY 2000 BP 479 EP 480 DI 10.1109/ICIMW.2000.893114 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BR44B UT WOS:000166423000203 ER PT S AU Johnson, AS AF Johnson, AS BE Vandoni, CE TI OO design and implementation: Java and Java analysis studio SO 2000 CERN SCHOOL OF COMPUTING SE C E R N REPORTS LA English DT Proceedings Paper CT 2000 CERN School of Computing Conference CY SEP 17-30, 2000 CL MARATHON, GREECE SP CERN AB We present an overview of the Java language, Java virtual machine, and the large set of standard libraries and extensions available for Java, and provide a discussion of issues that effect Java performance. This is followed by an introduction to Java Analysis Studio (JAS), a tool written in Java, and in which Java is the language used to perform data analysis. We will also explore how OO techniques have been used to built a system from modular components including visualization, fitting and data-access components that can be used together, or on their own. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Johnson, AS (reprint author), Stanford Linear Accelerator Ctr, POB 4349, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND SN 0007-8328 BN 92-9083-178-2 J9 CERN REPORT PY 2000 VL 2000 IS 13 BP 99 EP 105 PG 7 WC Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BT50N UT WOS:000173158800008 ER PT S AU Tierney, B Johnston, W Lee, J AF Tierney, B Johnston, W Lee, J BE Vandoni, CE TI A cache-based data intensive distributed computing architecture for "grid" applications SO 2000 CERN SCHOOL OF COMPUTING SE C E R N REPORTS LA English DT Proceedings Paper CT 2000 CERN School of Computing Conference CY SEP 17-30, 2000 CL MARATHON, GREECE SP CERN AB Modern scientific computing involves organizing, moving, visualizing, and analyzing massive amounts of data from around the world, as well as employing large-scale computation. The distributed systems that solve large-scale problems will always involve aggregating and scheduling many resources. Data must be located and staged, cache and network capacity must be available at the same time as computing capacity, etc. Every aspect of such a system is dynamic: locating and scheduling resources, adapting running application systems to availability and congestion in the middleware and infrastructure, responding to human interaction, etc. The technologies, the middleware services, and the architectures that are used to build useful highspeed, wide area distributed systems, constitute the field of data intensive computing, and are sometimes referred to as the "Data Grid". This paper explores the use of a network data cache in a Data Grid environment. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Tierney, B (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU C E R N PI GENEVA PA MEYRIN, CH-1211 GENEVA, SWITZERLAND SN 0007-8328 BN 92-9083-178-2 J9 CERN REPORT PY 2000 VL 2000 IS 13 BP 155 EP 162 PG 8 WC Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BT50N UT WOS:000173158800012 ER PT B AU Wunsch, TF Kinard, JR Manginell, RP Solomon, OM Lipe, TE AF Wunsch, TF Kinard, JR Manginell, RP Solomon, OM Lipe, TE BE Hunter, J Johnson, L TI A new fabrication process for planar thin-film multijunction thermal converters SO 2000 CONFERENCE ON PRECISION ELECTROMAGNETIC MEASUREMENTS DIGEST LA English DT Proceedings Paper CT Conference on Precision Electromagnetic Measurements (CPEM 2000) CY MAY 14-19, 2000 CL SYDNEY, AUSTRALIA SP Int Bur Weights & Measures, IEEE Instrumentat & Measurement Soc, Natl Inst Stand & Technol, Natl Res Council Canada, Union Radio Sci Int, CSIRO, Natl Measurement Lab, Natl Facil, Ind Sci Resources, Ind Res Ltd, Nat Assoc Testing Authorities, Stand Australia, Natl Stand Commiss, Joint Accreditat Syst Australia & New Zealand, Korea Res Inst Stand & Sci, Ctr Measurement Stand, ITRI, Fluke Corp, Int Union Pure & Appl Phys, Natl Conf Stand Labs, Oxford Instruments, Prema Prazisionselektron, Metrol Soc Australia, Texas Instruments, TransGrid AB Advanced thin film processing and packaging technologies are employed in the fabrication of new planar thin-film multifunction thermal conveners. The processing, packaging, and design features build on experience gained from prior NIST demonstrations of thin-film converters with optimizations for improved sensitivity, bandwidth, manufacturability, and reliability. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wunsch, TF (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5745-0 PY 2000 BP 387 EP 388 DI 10.1109/CPEM.2000.851038 PG 2 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ82P UT WOS:000089712400196 ER PT S AU Dressendorfer, PV Peterson, DA Reber, CA AF Dressendorfer, PV Peterson, DA Reber, CA GP SPIE SPIE TI MEMS packaging - Current issues and approaches SO 2000 HD INTERNATIONAL CONFERENCE ON HIGH-DENSITY INTERCONNECT AND SYSTEMS PACKAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT International Conference on High-Density Interconnect and Systems Packaging CY APR 25-28, 2000 CL DENVER, CO SP Int Microelectr & Packaging Soc, CMP Media DE MEMS; packaging; assembly; die separation; wafer bonding; stress; hermeticity ID SURFACE-MICROMACHINED ACCELEROMETER; VACUUM; MICROSENSORS AB The assembly and packaging of MEMS (Microelectromechanical Systems) devices raise a number of issues over and above those normally associated with the assembly of standard microelectronic circuits. MEMS components include a variety of sensors, microengines, optical components, and other devices. They often have exposed mechanical structures which during assembly require particulate control, free space in the package, non-contact handling procedures, low-stress die attach, precision die placement, unique process schedules, hermetic sealing in controlled environments (including vacuum), and other special constraints. These constraints force changes in the techniques used to separate die on a wafer, in the types of packages which can be used, in the assembly processes and materials, and in the sealing environment and process. This paper discusses a number of these issues and provides information on approaches being taken or proposed to address them. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dressendorfer, PV (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 33 TC 5 Z9 5 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-930815-60-2 J9 P SOC PHOTO-OPT INS PY 2000 VL 4217 BP 208 EP 213 PG 6 WC Engineering, Electrical & Electronic; Physics, Condensed Matter SC Engineering; Physics GA BR83G UT WOS:000167729500038 ER PT B AU Fischer, AJ Klem, JF Choquette, KD Blum, O Allerman, AA Fritz, IJ Kurtz, SR Breiland, WG Sieg, R Geib, KM Scott, JW Naone, RL AF Fischer, AJ Klem, JF Choquette, KD Blum, O Allerman, AA Fritz, IJ Kurtz, SR Breiland, WG Sieg, R Geib, KM Scott, JW Naone, RL GP IEEE IEEE TI Continuous wave operation of 1.3 mu m vertical cavity InGaAsN quantum well lasers SO 2000 IEEE 17TH INTERNATIONAL SEMICONDUCTOR LASER CONFERENCE, CONFERENCE DIGEST LA English DT Proceedings Paper CT 17th IEEE International Semiconductor Laser Conference CY SEP 25-28, 2000 CL MONTEREY, CA SP IEEE Lasers & Electro Opt Soc C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Fischer, AJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6260-8 PY 2000 BP 7 EP 8 DI 10.1109/ISLC.2000.882262 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BR46J UT WOS:000166520900004 ER PT B AU Zutavern, FJ Baca, AG Chow, WW Hafich, MJ Hjalmarson, HP Loubriel, GM Mar, A O'Malley, MW Vawter, GA AF Zutavern, FJ Baca, AG Chow, WW Hafich, MJ Hjalmarson, HP Loubriel, GM Mar, A O'Malley, MW Vawter, GA GP IEEE IEEE TI Semiconductor e-h plasma lasers SO 2000 IEEE 17TH INTERNATIONAL SEMICONDUCTOR LASER CONFERENCE, CONFERENCE DIGEST LA English DT Proceedings Paper CT 17th IEEE International Semiconductor Laser Conference CY SEP 25-28, 2000 CL MONTEREY, CA SP IEEE Lasers & Electro Opt Soc C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Zutavern, FJ (reprint author), Sandia Natl Labs, MS 1153,POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6260-8 PY 2000 BP 43 EP 44 DI 10.1109/ISLC.2000.882279 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BR46J UT WOS:000166520900021 ER PT B AU Choquette, KD Fischer, AJ Geib, KM Hadley, GR Allerman, AA Hindi, JJ AF Choquette, KD Fischer, AJ Geib, KM Hadley, GR Allerman, AA Hindi, JJ GP IEEE IEEE TI High single mode operation from hybrid ion implanted/selectively oxidized VCSELs SO 2000 IEEE 17TH INTERNATIONAL SEMICONDUCTOR LASER CONFERENCE, CONFERENCE DIGEST LA English DT Proceedings Paper CT 17th IEEE International Semiconductor Laser Conference CY SEP 25-28, 2000 CL MONTEREY, CA SP IEEE Lasers & Electro Opt Soc C1 Sandia Natl Labs, Ctr Compound Semicond Sci & Technol, Albuquerque, NM 87185 USA. RP Choquette, KD (reprint author), Sandia Natl Labs, Ctr Compound Semicond Sci & Technol, POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6260-8 PY 2000 BP 59 EP 60 DI 10.1109/ISLC.2000.882287 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BR46J UT WOS:000166520900029 ER PT S AU Hughes, RJ Buttler, WT Kwiat, PG Lamoreaux, SK Morgan, GL Nordholt, JE Peterson, CG AF Hughes, RJ Buttler, WT Kwiat, PG Lamoreaux, SK Morgan, GL Nordholt, JE Peterson, CG GP IEEE IEEE TI Quantum cryptography for secure satellite communications SO 2000 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOL 1 SE IEEE Aerospace Conference Proceedings LA English DT Proceedings Paper CT 2000 IEEE Aerospace Conference CY MAR 18-25, 2000 CL BIG SKY, MT SP IEEE, Aerosp & Electr Syst Soc ID KEY DISTRIBUTION; PRIVACY AMPLIFICATION; OPTICAL-FIBER; PHOTONS; CANNOT; LIGHT AB Quantum cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics and information-theoretically secure post-processing methods. An adversary can neither successfully tap the quantum transmissions, nor evade detection, owing to Heisenberg's uncertainty principle. In this paper we describe the theory of quantum cryptography, and recent results from our experimental free-space system with which we have demonstrated the feasibility of quantum key generation over a point-to-point outdoor atmospheric path in daylight. We achieved a transmission distance of 0.5 km, which was limited only by the length of the test range. Our results provide strong evidence that cryptographic key material could be generated on demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed on orbit for encrypting the uplinked command path and downlinked data path; or to distribute keys between widely-separated ground stations with a satellite relay, enabling encrypted communications over even inter-continental distances. We present a feasibility analysis of surface-to-satellite quantum key generation. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM hughes@lanl.gov NR 42 TC 3 Z9 3 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-5846-5 J9 AEROSP CONF PROC PY 2000 BP 191 EP 200 PG 10 WC Engineering, Aerospace SC Engineering GA BQ98E UT WOS:000165245300020 ER PT S AU Nordholt, JE Young, DT Funsten, HO AF Nordholt, JE Young, DT Funsten, HO GP IEEE IEEE TI Plasma Experiment for Planetary Exploration (PEPE) on DS1 SO 2000 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOL 7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 2000 IEEE Aerospace Conference CY MAR 18-25, 2000 CL BIG SKY, MT SP IEEE, Aerosp & Electr Syst Soc ID ION MASS-SPECTROMETER AB The Plasma Experiment for Planetary Exploration, PEPE (pronounced PEPE), is st space plasma energy, angle, and mass/charge spectrometer now taking data aboard the Deep Space 1 (DS1) spacecraft. PEPE required several advanced technologies and specialized construction techniques to meet its targeted cost, schedule, mass, power, and volume reductions compared to previous plasma sensor packages such as the NASA Cassini mission Plasma Spectrometer(CAPS). It was designed to validate technologies and techniques for these resource savings so that future plasma instrumentation can use fewer resources and continue to have frequent access to space. PEPE was also designed to monitor the effect that the ion engine on DS1 has on the spacecraft environment and determine the impact of ion engines on future scientific instrumentation and measurements. PEPE has produced both high quality data and science, fully demonstrating that its new technologies can produce a viable instrument compatible with an ion propelled spacecraft. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Nordholt, JE (reprint author), Univ Calif Los Alamos Natl Lab, M-S D466, Los Alamos, NM 87545 USA. RI Funsten, Herbert/A-5702-2015 OI Funsten, Herbert/0000-0002-6817-1039 NR 8 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-5846-5 J9 AEROSP CONF PROC PY 2000 BP 597 EP 607 PG 11 WC Engineering, Aerospace SC Engineering GA BQ98L UT WOS:000165246200059 ER PT S AU Ng, LC Burnett, GC Holzrichter, JF Gable, TJ AF Ng, LC Burnett, GC Holzrichter, JF Gable, TJ GP IEEE, SIGNAL PROC SOC IEEE, SIGNAL PROC SOC IEEE, SIGNAL PROC SOC TI Denoising of human speech using combined Acoustic and EM Sensor signal processing SO 2000 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING, PROCEEDINGS, VOLS I-VI SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech, and Signal Processing CY JUN 05-09, 2000 CL ISTANBUL, TURKEY SP IEEE Signal Proc Soc AB Low Power EM radar-like sensors have made it possible to measure properties of the human speech production system in real-time, without acoustic interference. This greatly enhances the quality and quantify of information for many speech related applications. See Holzrichter, Burnett, Ng, and Lea, J. Acoustic. Sec. Am. 103 (1) 622 (1998). By using combined Glottal-EM-Sensor- and Acoustic-signals, segments of voiced, unvoiced, and no-speech can be reliably defined. Real-time de-noising filters can be constructed to remove noise from the user s corresponding speech signal. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Ng, LC (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-3, Livermore, CA 94550 USA. NR 4 TC 0 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-6293-4 J9 INT CONF ACOUST SPEE PY 2000 BP 229 EP 232 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Information Systems; Engineering, Electrical & Electronic SC Acoustics; Computer Science; Engineering GA BQ62X UT WOS:000088999500058 ER PT B AU Smith, PA Campbell, DV AF Smith, PA Campbell, DV BE Malaiya, YK Sachdev, M Menon, SM TI A practical implementation of BICS for safety-critical applications SO 2000 IEEE INTERNATIONAL WORKSHOP ON DEFECT BASED TESTING, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Workshop on Defect Based Testing CY APR 30, 2000 CL MONTREAL, CANADA SP IEEE Comp Soc, Test Technol Tech Comm ID BURN-IN AB This paper presents the challenges and solutions of applying Built-In-Current Sensors (BICS) to a safety-critical IC design for the purpose of in-situ state-of-health monitoring. The developed Quiescent Current Monitor (QCM) system consists of multiple BICS and digital control logic. The QCM BICS can detect leakage current as low as 4 muA, run at system speed, and has relatively low real estate overhead. The QCM digital logic incorporates extensive debug capability and Built-In-Self-Test (BIST). We performed analog and digital simulations of the integrated BICS, and performed layout and tape-out of the design. Silicon is now in fabrication. Results to date show that, for some systems, BICS can be a practical and relatively inexpensive method for providing state-of-health monitoring of safety-critical microelectronics. C1 Sandia Natl Labs, Microsyst Sci Technol & Components Ctr, Digital Microelect Dept 1735, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, Microsyst Sci Technol & Components Ctr, Digital Microelect Dept 1735, MS 1072, Albuquerque, NM 87185 USA. EM pasmith@sandia.gov; dvcampbo@sandia.gov NR 14 TC 4 Z9 4 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0637-2 PY 2000 BP 51 EP 56 DI 10.1109/DBT.2000.843690 PG 6 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BQ92F UT WOS:000090089300008 ER PT B AU Spahn, OB Sullivan, C Burkhart, J Tigges, C Garcia, E AF Spahn, OB Sullivan, C Burkhart, J Tigges, C Garcia, E GP IEEE IEEE TI GaAs-based microelectromechanical waveguide switch SO 2000 IEEE/LEOS INTERNATIONAL CONFERENCE ON OPTICAL MEMS LA English DT Proceedings Paper CT IEEE/LEOS International Conference on Optical MEMS CY AUG 21-24, 2000 CL KAUAI, HI SP IEEE, Laser & Electro Opt Soc, Cronos Integrated Microsyst, Lucent Technologies, Bell Labs, Opt Micro Machines, Tellium Inc C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Spahn, OB (reprint author), Sandia Natl Labs, MS0603, Albuquerque, NM 87185 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6257-8 PY 2000 BP 41 EP 42 DI 10.1109/OMEMS.2000.879617 PG 2 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BQ99N UT WOS:000165310300019 ER PT B AU Spahn, OB Tigges, C Shul, R Rodgers, S Polosky, M AF Spahn, OB Tigges, C Shul, R Rodgers, S Polosky, M GP IEEE IEEE TI High optical power handling of pop-up microelectromechanical mirrors SO 2000 IEEE/LEOS INTERNATIONAL CONFERENCE ON OPTICAL MEMS LA English DT Proceedings Paper CT IEEE/LEOS International Conference on Optical MEMS CY AUG 21-24, 2000 CL KAUAI, HI SP IEEE, Laser & Electro Opt Soc, Cronos Integrated Microsyst, Lucent Technologies, Bell Labs, Opt Micro Machines, Tellium Inc C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Spahn, OB (reprint author), Sandia Natl Labs, MS0603, Albuquerque, NM 87185 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6257-8 PY 2000 BP 51 EP 52 DI 10.1109/OMEMS.2000.879622 PG 2 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BQ99N UT WOS:000165310300024 ER PT S AU Tamura, F Tantawi, SG AF Tamura, F Tantawi, SG BE Perkins, T TI Multi-megawatt X-band semiconductor microwave switches SO 2000 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-3 SE IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE MTT-S International Microwave Symposium (IMS2000) CY JUN 11-16, 2000 CL BOSTON, MA SP IEEE, MTT S AB We describe concepts for high power semiconductor RF switches, designed to handle 100MW-order signal at X-band, We describe an abstract design methodology, and derive a general scaling law for these switches. We also present a design and experimental work of a switch operating at TE01 mode in over-moded circular waveguides. The switch is composed of array of tee junction elements that have PIN/NIP diode array window in the third arm. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Menlo Park, CA 94025 USA. RP Tamura, F (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Menlo Park, CA 94025 USA. OI Tamura, Fumihiko/0000-0002-2585-2440 NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0149-645X BN 0-7803-5687-X J9 IEEE MTT-S PY 2000 BP 1731 EP 1734 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BR55W UT WOS:000166811000405 ER PT S AU Hietala, VM Casalnuovo, SA Heller, EJ Wendt, JR Frye-Mason, GC Baca, AG AF Hietala, VM Casalnuovo, SA Heller, EJ Wendt, JR Frye-Mason, GC Baca, AG BE Perkins, T TI Monolithic GaAs surface acoustic wave chemical microsensor array SO 2000 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-3 SE IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE MTT-S International Microwave Symposium (IMS2000) CY JUN 11-16, 2000 CL BOSTON, MA SP IEEE, MTT S AB A four-channel surface acoustic wave (SAW) chemical sensor array with associated RF electronics is monolithically integrated onto one GaAs IC. The sensor operates at 690 MHz from an on-chip SAW based oscillator and provides simple DC voltage outputs by using integrated phase detectors. This sensor array represents a significant advance in microsensor technology offering miniaturization, increased chemical selectivity, simplified system assembly, improved sensitivity, and inherent temperature compensation. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hietala, VM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0149-645X BN 0-7803-5687-X J9 IEEE MTT-S PY 2000 BP 1965 EP 1968 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BR55W UT WOS:000166811000461 ER PT B AU Hauer, JF Trudnowski, DJ AF Hauer, JF Trudnowski, DJ GP IEEE IEEE TI Using the coherency function in measurement based small-signal analysis of large power systems SO 2000 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, CONFERENCE PROCEEDINGS, VOLS 1-4 LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 16-20, 2000 CL SEATTLE, WA SP Power Engn Soc, IEEE DE coherency function; observability; modal participation; power system monitoring AB Load switching and other random phenomena in a loosely connected power system produce ambient process noise that contains much useful information about oscillatory dynamics. The estimated coherency between two signals, in particular, has long been taken as a heuristic indicator for the frequency and strength of modal interactions along specific network paths. The conjecture is that a sharp peak in estimated coherency corresponds to a mode that is common to both signals. Such information is useful in mode shape estimation, and as a guide to signal selection for multi-output Prony analysis. These results follow from known bias properties of the estimator, and require that the signals contain substantial levels of uncorrelated process noise in the frequency band of interest. As yet this "orthogonal" noise is neither modeled nor well understood. Observations suggest that it is a basic property of large power systems, and that it tends to increase with geographical separation of the signal sources. Recent growth of wide area measurement facilities in the Western North America power system have encouraged system tests that permit such phenomena to be examined more closely. This presentation, prepared for the Panel Session on Recent Applications of Small-Signal Stability Analysis Techniques. provides a summary of recent results. C1 Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. RP Hauer, JF (reprint author), Battelle Mem Inst, Pacific NW Natl Labs, Richland, WA 99352 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6420-1 PY 2000 BP 809 EP 811 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA BQ74M UT WOS:000089398700152 ER PT B AU Peng, FZ Tolbert, LM AF Peng, FZ Tolbert, LM GP IEEE IEEE TI Compensation of non-active current in power systems - Definitions from compensation standpoint- SO 2000 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, CONFERENCE PROCEEDINGS, VOLS 1-4 LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 16-20, 2000 CL SEATTLE, WA SP Power Engn Soc, IEEE DE non-active current; non-active power; reactive current; reactive power; harmonic current; harmonic power; active power; apparent power; var compensation AB Many definitions have been formulated to characterize, detect, and measure active and non-active current and power for non-sinusoidal and non-periodic waveforms in electric systems. This paper presents definitions and compensation of non-active current from the compensation standpoint. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Peng, FZ (reprint author), Oak Ridge Natl Lab, POB 2009,Bldg 9102-1, Oak Ridge, TN 37831 USA. OI Tolbert, Leon/0000-0002-7285-609X NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6420-1 PY 2000 BP 983 EP 987 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA BQ74M UT WOS:000089398700193 ER PT B AU Boyes, JD AF Boyes, JD GP IEEE IEEE TI Overview of energy storage applications SO 2000 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, CONFERENCE PROCEEDINGS, VOLS 1-4 LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 16-20, 2000 CL SEATTLE, WA SP Power Engn Soc, IEEE C1 Sandia Natl Labs, Energy Storage Syst Program, Livermore, CA 94550 USA. RP Boyes, JD (reprint author), Sandia Natl Labs, Energy Storage Syst Program, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6420-1 PY 2000 BP 1514 EP 1516 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA BQ74M UT WOS:000089398700293 ER PT B AU Boyes, JD Clark, NH AF Boyes, JD Clark, NH GP IEEE IEEE TI Flywheels and super conducting magnetic energy storage SO 2000 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, CONFERENCE PROCEEDINGS, VOLS 1-4 LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 16-20, 2000 CL SEATTLE, WA SP Power Engn Soc, IEEE C1 Sandia Natl Labs, Energy Storage Program, Livermore, CA 94550 USA. RP Boyes, JD (reprint author), Sandia Natl Labs, Energy Storage Program, Livermore, CA 94550 USA. NR 1 TC 0 Z9 0 U1 1 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6420-1 PY 2000 BP 1548 EP 1550 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA BQ74M UT WOS:000089398700300 ER PT B AU Short, W AF Short, W GP IEEE IEEE TI The potential of renewables to address global climate change SO 2000 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, CONFERENCE PROCEEDINGS, VOLS 1-4 LA English DT Meeting Abstract CT IEEE Power-Engineering-Society Summer Meeting CY JUL 16-20, 2000 CL SEATTLE, WA SP Power Engn Soc, IEEE C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6420-1 PY 2000 BP 1779 EP 1779 PG 1 WC Engineering, Electrical & Electronic SC Engineering GA BQ74M UT WOS:000089398700337 ER PT B AU Kroposki, B DeBlasio, R AF Kroposki, B DeBlasio, R GP IEEE IEEE TI Technologies for the new millennium: Photovoltaics as a distributed resource SO 2000 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, CONFERENCE PROCEEDINGS, VOLS 1-4 LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 16-20, 2000 CL SEATTLE, WA SP Power Engn Soc, IEEE DE photovoltaics; distributed resource; standards; utility interconnection; grid-connected; distributed generation ID SYSTEM AB As we enter the new millennium, photovoltaics (PV) is emerging as an important distributed resource. PV gives both the benefits of a distributed resource and a clean power source. Because PV can be located at both residential and commercial locations, it can be used to reduce peak demand when its output is properly matched with load usage. It can also improve asset utilization by requiring less large capital generation spending and delaying some equipment replacement. With the price of some grid-connected PV systems expected To reach $3/W in the next 5 years, PV will become an economical option for distributed power generation. One of the most important aspects of establishing PV as a distributed resource is standardizing the requirements for grid connection. IEEE Standards Coordinating Committee (SCC) 21 has recently published IEEE Std 929 "Recommend Practice for Utility Interface of Photovoltaic Systems." This recommended practice details power quality, safety, and protection requirements for connection to the utility grid. This paper describes what types of PV systems are available, what the benefits are for PV systems, and what the interconnection issues and solutions are for using PV as a distributed resource. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kroposki, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 19 TC 0 Z9 0 U1 2 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6420-1 PY 2000 BP 1798 EP 1801 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA BQ74M UT WOS:000089398700343 ER PT B AU Muljadi, E Nix, G Bialasiewicz, JT AF Muljadi, E Nix, G Bialasiewicz, JT GP IEEE IEEE TI Analysis of the dynamics of a wind-turbine water-pumping system SO 2000 IEEE POWER ENGINEERING SOCIETY SUMMER MEETING, CONFERENCE PROCEEDINGS, VOLS 1-4 LA English DT Proceedings Paper CT IEEE Power-Engineering-Society Summer Meeting CY JUL 16-20, 2000 CL SEATTLE, WA SP Power Engn Soc, IEEE AB We analyzed a wind-turbine water-pumping system, which consists of a wind turbine with a permanent magnet generator electrically coupled with a water pump via a motor-generator configuration. Beginning with a short summary of the system's steady-state analysis, we will show how the success of the start-up process and how the system's performance depends on the proper choice of water pump characteristics. We studied the dependence of the water pump start-up process on the kinetic energy stored in the wind turbine rotor. In this analysis, we will also discuss the cut-in and cut-off process in the wind-turbine water-pumping system. We support our analysis with the simulation results obtained for a water-pumping system, which consists of a Bergey Windpower Company, Inc. (BWC). EXCEL wind turbine system and a water pump driven by the Franklin 7.5 horsepower (hp) induction motor (Model 234318). The simulations were performed using the RPM-Sim simulator (Renewable-energy Power-system Simulator), was developed at the Laboratory's National Modular National Wind which Renewable Energy Technology Center. C1 Natl Renewable Energy Lab, Natl Wind Technol Ctr, Golden, CO 80401 USA. RP Muljadi, E (reprint author), Natl Renewable Energy Lab, Natl Wind Technol Ctr, 1617 Cole Blvd, Golden, CO 80401 USA. NR 9 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6420-1 PY 2000 BP 2506 EP 2519 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA BQ74M UT WOS:000089398700466 ER PT B AU Brubaker, MA Nelson, JK AF Brubaker, MA Nelson, JK GP IEEE IEEE IEEE TI A parametric study of streaming electrification in a full-scale core-form transformer winding using a network-based model SO 2000 IEEE POWER ENGINEERING SOCIETY WINTER MEETING - VOLS 1-4, CONFERENCE PROCEEDINGS LA English DT Meeting Abstract CT 2000 Winter Meeting of the IEEE Power Engineering-Society CY JAN 23-27, 2000 CL SINGAPORE, SINGAPORE SP IEEE Power Engn Soc, IEEE Networking World C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5935-6 PY 2000 BP 2205 EP 2205 PG 1 WC Engineering, Electrical & Electronic SC Engineering GA BQ45S UT WOS:000088388600432 ER PT S AU Tobin, KW Karnowski, TP Lakhani, F AF Tobin, KW Karnowski, TP Lakhani, F GP IEEE IEEE IEEE TI The use of historical defect imagery for yield learning SO 2000 IEEE/SEMI ADVANCED SEMICONDUCTOR MANUFACTURING CONFERENCE AND WORKSHOP SE ADVANCED SEMICONDUCTOR MANUFACTURING CONFERENCE AND WORKSHOP - PROCEEDINGS LA English DT Proceedings Paper CT 11th Annual IEEE/SEMI Advanced Semiconductor Manufacturing Conference and Workshop (ASMC 2000) CY SEP 12-14, 2000 CL BOSTON, MA SP IEEE, Semiconductor Equipment & Mat Int, IEEE Electr Devices Soc, IEEE Components Packaging & Mfg Technol Soc DE yield management; yield learning; image management; datamining; content-based image retrieval; automated image retrieval; approximate nearest-neighbors searching; visual similarity AB The rapid identification of yield detracting mechanisms through integrated yield management is the primary goal of defect sourcing and yield learning. At future technology nodes, yield learning must proceed at an accelerated rate to maintain current defect sourcing cycle times despite the growth in circuit complexity and the amount of data acquired on a given wafer lot [1]. As integrated circuit fabrication processes increase in complexity, it has been determined that data collection, retention, and retrieval rates will continue to increase at an alarming tate. Oak Ridge National Laboratory (ORNL) has been working with International SEMATECH to develop methods for managing the targe volumes of image data that are being generated to monitor the status of the manufacturing process [2, 3]. This data contains an historical record that can be used to assist the yield engineer in the rapid resolution of manufacturing problems. To date there are no efficient methods of sorting and analyzing the vast repositories of imagery collected by off-line review teals for failure analysis, particle monitoring, line width control, and overlay metrology. In this paper we will describe a new method for organizing, searching, and retrieving imagery using a query image to extract images from a large image database based on visual similarity. C1 Oak Ridge Natl Lab, Image Sci & Machine Vis Grp, Oak Ridge, TN 37831 USA. RP Tobin, KW (reprint author), Oak Ridge Natl Lab, Image Sci & Machine Vis Grp, Oak Ridge, TN 37831 USA. RI Escarabajal, Juan Antonio/C-5644-2012 NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1078-8743 BN 0-7803-5921-6 J9 ASMC PROC PY 2000 BP 18 EP 25 DI 10.1109/ASMC.2000.902553 PG 8 WC Engineering, Industrial; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BR45U UT WOS:000166472900004 ER PT B AU Gokhale, M Stone, J Arnold, J Kalinowski, M AF Gokhale, M Stone, J Arnold, J Kalinowski, M BE Hutchings, BL TI Stream-oriented FPGA computing in the Streams-C high level language SO 2000 IEEE SYMPOSIUM ON FIELD-PROGRAMMABLE CUSTOM COMPUTING MACHINES, PROCEEDINGS SE Annual IEEE Symposium on Field-Programmable Custom Computing Machines LA English DT Proceedings Paper CT IEEE Symposium on Field-Programmable Custom Computing Machines CY APR 17-19, 2000 CL NAPA VALLEY, CA SP IEEE, Comp Soc, Tech Comm Comp Architecture AB Stream oriented processing is an important methodology used in FPGA-based parallel processing. Characteristics of stream-oriented computing include high-data-rate flow of one or more data sources; fixed size, small stream payload tone byte to one word); compute-intensive operations, usually low precision fixed point, on the data stream; access to small local memories holding coefficients and other constants; and occasional synchronization between computational phases. In this paper we describe language constructs, compiler technology, and hardware/software libraries embodying the Streams-C system which has been developed to support stream-oriented computation on FPGA-based parallel computers. The language is implemented as a small set of library functions callable from a C language program. The Streams-C compiler synthesizes hardware circuits for multiple FPGAs as well as a multi-threaded software program for the control processor Our system includes a functional simulation environment based on POSIX threads, allowing the programmer to simulate the collection. of parallel processes and their communication at the functional level. Finally we present an: application written both in Streams-C and hand-coded in VHDL. Compared to the hand-crafted design, the Streams-C-generated circuit takes 3x the area and runs at 1/2 the clock rate. In terms of time to market, the hand-done design took a month to develop by an experienced hardware developer The Streams-C design took a couple of days, for a productivity increase of 10x. C1 Univ Calif Los Alamos Natl Lab, Space Data Syst grp, Los Alamos, NM 87545 USA. RP Gokhale, M (reprint author), Univ Calif Los Alamos Natl Lab, Space Data Syst grp, MS D440, Los Alamos, NM 87545 USA. EM maya@lanl.gov; jmstone@nerc.com; jmarnold@znet.com; mirek@sarnoff.com NR 6 TC 35 Z9 36 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0871-5 J9 ANN IEEE SYM FIELD P PY 2000 BP 49 EP 56 DI 10.1109/FPGA.2000.903392 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BR56S UT WOS:000166816100005 ER PT S AU Telschow, KL Deason, VA Cottle, DL Larson, JD AF Telschow, KL Deason, VA Cottle, DL Larson, JD BE Schneider, SC Levy, M McAvoy, BR TI UHF acoustic microscopic imaging of resonator motion SO 2000 IEEE ULTRASONICS SYMPOSIUM PROCEEDINGS, VOLS 1 AND 2 SE ULTRASONICS SYMPOSIUM LA English DT Proceedings Paper CT IEEE Ultrasonics Symposium CY OCT 22-25, 2000 CL SAN JUAN, PR SP IEEE Ultrason, Ferroelect, & Frequency Control Soc AB An important characteristic of acoustic resonator design at ultra high frequencies (UHF) is the efficiency of the device, which is affected by leakage radiation beyond the active transducer area. In order to directly measure leakage radiation, acoustic microscopic imaging of the ultrasonic resonant motion at 880 MHz has been performed with an autocompensating interferometer and heterodyne demodulation. A method of interferometric detection based on two-wave mixing in a photorefractive material was employed to allow for automatic quadrature detection and compensation of low frequency vibrational effects. Heterodyne phase modulation was used to produce a beat frequency of 25 kHz to allow for narrowband detection utilizing lock-in amplifier techniques. A sensitivity of 5x10(-5) nm was obtained with a 10 sec time constant and detection light power of about 0.5 mW. Over 90 dB dynamic drive range was recorded at the UHF operating frequency without vibration isolation of the microscope or optics. The method of calibration and results of scanning measurements on various resonators are presented and discussed in connection with current limitations and future improvements. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Telschow, KL (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 6 TC 5 Z9 5 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1051-0117 BN 0-7803-6365-5 J9 ULTRASON PY 2000 BP 631 EP 634 PG 4 WC Acoustics; Engineering, Industrial; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Engineering; Radiology, Nuclear Medicine & Medical Imaging GA BT07X UT WOS:000171881300133 ER PT S AU Kaduchak, G Sinha, DN AF Kaduchak, G Sinha, DN BE Schneider, SC Levy, M McAvoy, BR TI Effects of diffraction on the measurement of the acoustic properties of liquids in thin-walled containers SO 2000 IEEE ULTRASONICS SYMPOSIUM PROCEEDINGS, VOLS 1 AND 2 SE ULTRASONICS SYMPOSIUM LA English DT Proceedings Paper CT IEEE Ultrasonics Symposium CY OCT 22-25, 2000 CL SAN JUAN, PR SP IEEE Ultrason, Ferroelect, & Frequency Control Soc AB A simple method which does not require calibration with a reference liquid for the determination of attenuation and density of a fluid contained within a thin-walled cell is demonstrated. The method relies on temporally filtering the impulse response of the system to partially deconvolve the transfer function associated with the wall. Experiments are conducted on cells of differing material construction and wall thickness which demonstrate the effectiveness of this method in obtaining accurate near-field measurements of density and attenuation. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kaduchak, G (reprint author), Los Alamos Natl Lab, MS D429, Los Alamos, NM 87545 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1051-0117 BN 0-7803-6365-5 J9 ULTRASON PY 2000 BP 809 EP 813 PG 3 WC Acoustics; Engineering, Industrial; Radiology, Nuclear Medicine & Medical Imaging SC Acoustics; Engineering; Radiology, Nuclear Medicine & Medical Imaging GA BT07X UT WOS:000171881300172 ER PT B AU Vella, MC Tysinger, R Reilly, M Brown, B AF Vella, MC Tysinger, R Reilly, M Brown, B BE Ryssel, H Frey, L Gyulai, J Glawischnig, H TI Decaborane ion source demonstration SO 2000 INTERNATIONAL CONFERENCE ON ION IMPLANTATION TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT 13th International Conference on Ion Implantation Technology (IIT 2000) CY SEP 17-22, 2000 CL ALPBACH, AUSTRIA SP Appl Mat, ATMI Mat, Atom Instruments GmbH, Bundesminist Wissensch & Verkehr Austria, Axcelis Technologies, European Commiss, Infineon Technologies, Kitzmann Brau KG, Matheson Trigas, Nissin Ion Equipment, SEMATECH, Univ Kyoto, VSEA AB This project demonstrated concept and feasibility of a proprietary high current decaborane ion source suitable for ultra shallow doping. This was motivated by the attractive scaling of decaborane ions for space charge dominated extraction and transport. A highly modified Bernas source was mounted on an NV-10/80 implanter. Using standard extraction and beamline components, 2.3 mA of boron nucleon current was produced in the form of B10Hx+ at 50 kV. Due to under dense plasma, beam current scaled linearly with extraction voltage. C1 LBNL, Berkeley, CA USA. RP Vella, MC (reprint author), LBNL, Berkeley, CA USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6462-7 PY 2000 BP 527 EP 529 PG 3 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BS31M UT WOS:000169430400125 ER PT B AU Barnes, SM Miller, SL Rodgers, MS Bitsie, F AF Barnes, SM Miller, SL Rodgers, MS Bitsie, F BE Laudon, M Romanowicz, B TI Torsional ratcheting actuating system SO 2000 INTERNATIONAL CONFERENCE ON MODELING AND SIMULATION OF MICROSYSTEMS, TECHNICAL PROCEEDINGS LA English DT Proceedings Paper CT 3rd International Conference on Modeling and Simulation of Microsystems CY MAR 27-29, 2000 CL San Diego, CA SP DARPA, Coyote Syst, MEMSCAP, SA, Mol Simulat Inc, Microcosm Technologies Inc, IEEE Electron Devices Soc, Motorola, Appl Computat Res Soc, Swiss Fed Inst Technol Lausanne, TIMA CMP Lab, Los Alamos Natl Lab, Int Assoc Math & Comp Modeling DE MEMS; actuator; electrostatic; comb; ratchet AB A new type of surface micromachined ratcheting actuation system has been developed at the Microelectronics Development Laboratory at Sandia National Laboratories. The actuator uses a torsional electrostatic comb drive that is coupled to an external ring gear through a ratcheting scheme. The actuator can be operated with a single square wave, has minimal rubbing surfaces, maximizes comb finger density, and can be used for open-loop position control. The prototypes function as intended with a minimum demonstrated operating voltage of 18V. The equations of motion are developed for the torsional electrostatic comb drive. The resonant frequency, voltage vs. displacement and force delivery characteristics are predicted and compared with the fabricated device's performance. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Barnes, SM (reprint author), Sandia Natl Labs, POB 5800,MS 1080, Albuquerque, NM 87185 USA. NR 8 TC 2 Z9 3 U1 0 U2 2 PU COMPUTATIONAL PUBLICATIONS PI CAMBRIDGE PA PUBISHING OFFICE, 308 ONE KENDALL SQ BLDG 600, CAMBRIDGE, MA 02139 USA BN 0-9666135-7-0 PY 2000 BP 273 EP 276 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BAO05 UT WOS:000223049100069 ER PT B AU Griffiths, SK Nilson, RH AF Griffiths, SK Nilson, RH BE Laudon, M Romanowicz, B TI Electroosmotic flow in a tube or channel at non-negligible zeta potentials SO 2000 INTERNATIONAL CONFERENCE ON MODELING AND SIMULATION OF MICROSYSTEMS, TECHNICAL PROCEEDINGS LA English DT Proceedings Paper CT 3rd International Conference on Modeling and Simulation of Microsystems CY MAR 27-29, 2000 CL San Diego, CA SP DARPA, Coyote Syst, MEMSCAP, SA, Mol Simulat Inc, Microcosm Technologies Inc, IEEE Electron Devices Soc, Motorola, Appl Computat Res Soc, Swiss Fed Inst Technol Lausanne, TIMA CMP Lab, Los Alamos Natl Lab, Int Assoc Math & Comp Modeling DE electroosmotic; electrokinetic; flow ID ELECTROKINETIC FLOW; CAPILLARIES AB Numerical methods based on a shooting technique are employed to determine the electric potential and fluid velocity in a tube and channel when the zeta potential is not small. In addition, new analytical solutions are presented for the fluid velocity in the extreme of a small Debye layer thickness. Asymptotic expressions for these results are provided for the limits of small and large zeta potentials. We find that increasing values of the wall potential always increase the mean fluid speed and yield a velocity profile having a more uniform speed near the center of the tube or channel. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Griffiths, SK (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU COMPUTATIONAL PUBLICATIONS PI CAMBRIDGE PA PUBISHING OFFICE, 308 ONE KENDALL SQ BLDG 600, CAMBRIDGE, MA 02139 USA BN 0-9666135-7-0 PY 2000 BP 532 EP 535 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BAO05 UT WOS:000223049100134 ER PT B AU Lee, SJ Jiles, DC AF Lee, SJ Jiles, DC BE Laudon, M Romanowicz, B TI Modeling and simulation of a permanent magnet array in elliptical configurations SO 2000 INTERNATIONAL CONFERENCE ON MODELING AND SIMULATION OF MICROSYSTEMS, TECHNICAL PROCEEDINGS LA English DT Proceedings Paper CT 3rd International Conference on Modeling and Simulation of Microsystems CY MAR 27-29, 2000 CL San Diego, CA SP DARPA, Coyote Syst, MEMSCAP, SA, Mol Simulat Inc, Microcosm Technologies Inc, IEEE Electron Devices Soc, Motorola, Appl Computat Res Soc, Swiss Fed Inst Technol Lausanne, TIMA CMP Lab, Los Alamos Natl Lab, Int Assoc Math & Comp Modeling DE permanent magnet magnet array; magnetic flux density; finite element method; modeling ID FIELD SOURCES AB Permanent magnet arrays have advantages for magnetic field generation over the traditional current based magnetic flux sources, such as electromagnets, in that they do not require a power supply and cooling system. Magnetic flux density above the magnetic remanence B-R of the permanent magnet material can be achieved by arranging the permanent magnet segments in the form of hollow cylindrical shells (magic rings), or hollow spherical shells (magic spheres). For many applications, it is important to design a permanent magnet array with the highest magnetic flux density for a given size and weight of permanent magnet material. In this paper, we report enhancement of magnetic flux density in the air gap by changing the cross sectional shape of the permanent magnet array into ellipse instead of a circle, as has been conventional until now. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Lee, SJ (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Jiles, David/H-9548-2012 NR 5 TC 0 Z9 0 U1 0 U2 0 PU COMPUTATIONAL PUBLICATIONS PI CAMBRIDGE PA PUBISHING OFFICE, 308 ONE KENDALL SQ BLDG 600, CAMBRIDGE, MA 02139 USA BN 0-9666135-7-0 PY 2000 BP 668 EP 671 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA BAO05 UT WOS:000223049100168 ER PT S AU Hoisie, A Lubeck, O Wasserman, H Petrini, F Alme, H AF Hoisie, A Lubeck, O Wasserman, H Petrini, F Alme, H BE Lilja, DJ TI A general predictive performance model for wavefront algorithms on clusters of SMPs SO 2000 INTERNATIONAL CONFERENCE ON PARALLEL PROCESSING, PROCEEDINGS SE Proceedings of the International Conference on Parallel Processing LA English DT Proceedings Paper CT International Conference on Parallel Processing (ICPP 2000) CY AUG 21-24, 2000 CL TORONTO, CANADA SP Int Assoc Comp & Commun AB We propose and validate a closed-end, analytical, general, predictive performance model for applications based on wavefront algorithms on clusters of SMPs. Wavefront algorithms are ubiquitous in parallel computing, since they represent a means of enabling parallelism in computations that contain recurrences. Our particular interest in wavefront algorithms derives from their use in discrete ordinates neutral particle transport computations representative of ASCI, but other important uses are well known The proposed model captures the tradeoff between processor utilization and communication requirements characteristics of wavefront algorithms. The general model can predict the performance of this class of applications on distributed architectures with a network of lower dimensionality compared to that of an MPP, of which clusters of SMPs are one example. We validate the model using a compact-application from the ASCI workload on a large-scale cluster of SGI Origin 2000s in existence at the Los Alamos National Laboratory. The proposed model validates well on all clusters configurations utilized. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, CIC-3, Los Alamos, NM 87545 USA. EM hoisie@lanl.gov; oml@lanl.gov; hjw@lanl.gov; fabrizio@lanl.gov; almehj@lanl.gov NR 9 TC 6 Z9 6 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 0190-3918 BN 0-7695-0768-9 J9 PROC INT CONF PARAL PY 2000 BP 219 EP 228 DI 10.1109/ICPP.2000.876127 PG 10 WC Computer Science, Theory & Methods SC Computer Science GA BQ74T UT WOS:000089400100024 ER PT S AU Feng, WC Tinnakornsrisuphap, P AF Feng, WC Tinnakornsrisuphap, P BE Lilja, DJ TI The adverse impact of the TCP congestion-control mechanism in heterogenous computing systems SO 2000 INTERNATIONAL CONFERENCE ON PARALLEL PROCESSING, PROCEEDINGS SE PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON PARALLEL PROCESSING LA English DT Proceedings Paper CT International Conference on Parallel Processing (ICPP 2000) CY AUG 21-24, 2000 CL TORONTO, CANADA SP Int Assoc Comp & Commun DE TCP; heterogeneous computing; high-performance networking; network traffic characterization AB Via experimental study we illustrate how TCP modulates application traffic in such a way as to adversely affect network performance in a heterogeneous computing system. Even when aggregate application traffic smooths out as more applications' traffic are multiplexed, TCP induces burstiness into the aggregate traffic load, and thus hurts network performance. This burstiness is particularly bad in TCP Reno, and Even worse when RED gateways are employed. Based on the results of this experimental study, rte then develop a stochastic model for TCP Reno to demonstrate how the burstiness bl TCP Reno can be modeled. C1 Univ Calif Los Alamos Natl Lab, Comp Informat & Commun Div, Los Alamos, NM 87545 USA. RP Feng, WC (reprint author), Univ Calif Los Alamos Natl Lab, Comp Informat & Commun Div, POB 1663, Los Alamos, NM 87545 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 0190-3918 BN 0-7695-0768-9 J9 PROC INT CONF PARAL PY 2000 BP 299 EP 306 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BQ74T UT WOS:000089400100032 ER PT B AU Theiss, SK Caturla, MJ Lenosky, TJ Sadigh, B de la Rubia, TD Giles, MD Foad, MA AF Theiss, SK Caturla, MJ Lenosky, TJ Sadigh, B de la Rubia, TD Giles, MD Foad, MA GP IEEE IEEE TI First-principles-based predictive simulations of B diffusion and activation in ion implanted Si SO 2000 INTERNATIONAL CONFERENCE ON SIMULATION OF SEMICONDUCTOR PROCESSES AND DEVICES LA English DT Proceedings Paper CT International Conference on Simulation of Semiconductor Processes and Devices CY SEP 06-08, 2000 CL SEATTLE, WA SP IEEE, Electr Devices Soc ID TRANSIENT ENHANCED DIFFUSION; KINETIC MONTE-CARLO; POINT-DEFECT; AB-INITIO; SILICON; BORON AB We present a kinetic: Monte Carlo model for boron diffusion, clustering and activation in ion implanted silicon. The input to the model is based on a combination of experimental data and ab initio calculations. The model shows that boron diffusion and activation are low while vacancy clusters are present in the system. As the vacancy clusters dissociate, boron becomes substitutional and the active fraction increases rapidly. At the same time, the total boron diffusion length also increases rapidly while interstitial clusters ripen. The final burst of boron diffusion occurs as the large interstitial clusters dissolve, but most of the transient diffusion of the implanted boron has already taken place by this time. We show that these results are in excellent agreement with experimental data on annealed dopant profiles and dopant activation as a function of annealing time. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Theiss, SK (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 18 TC 1 Z9 1 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6279-9 PY 2000 BP 18 EP 22 DI 10.1109/SISPAD.2000.871196 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BR43Y UT WOS:000166421700004 ER PT S AU Hector, SD Kearney, PA Montcalm, C Folta, JA Walton, CC Tong, WM Taylor, JS AF Hector, SD Kearney, PA Montcalm, C Folta, JA Walton, CC Tong, WM Taylor, JS BE Grenon, BJ Dao, GT TI Predictive model of the cost of extreme ultraviolet lithography masks SO 20TH ANNUAL BACUS SYMPOSIUM ON PHOTOMASK TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 20th Annual BACUS Symposium on Photomask Technology CY SEP 13-15, 2000 CL MONTEREY, CA SP BACUS, SPIE DE extreme ultraviolet lithography; masks; yield modeling; cost of ownership; next generation lithography; multilayers; yield modeling ID FABRICATION; ABSORBER; AREA; EUVL AB A model has been developed to predict the cost of extreme ultraviolet lithography (EUVL) masks. The mask blank for EUVL consists of a low thermal expansion material substrate having a square photomask form factor and is coated with reflective Mo/Si multilayers. Absorber layers are deposited on the multilayer and patterned. EUVL mask. patterning will use evolutionary improvements in mask patterning and repair equipment. One of the challenges in implementing EUVL is to economically fabricate multilayer-coated mask blanks with no printable defects. The model of mask cost assigns yield and time required for each of the steps in fabricating EUVL masks from purchase of a polished substrate to shipment of a patterned mask. Data from present multilayer coating processes and present mask patterning processes are used to estimate the future cost of EUVL masks. Several of the parameters that significantly influence predicted mask cost are discussed in detail. Future cost reduction of mask blanks is expected from learning on substrate fabrication, improvements in low defect multilayer coating to consistently obtain <0.005 defects cm(-2), and demonstration of multilayer smoothing which reduces the printability of substrate defects. The model predicts that the price range for EUVL masks in production will be $30-40K, which is comparable to the price of complex phase shift masks needed to use optical lithography for 70 nm critical dimension patterning. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Hector, SD (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 5508, Livermore, CA 94550 USA. NR 37 TC 4 Z9 4 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3849-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4186 BP 733 EP 748 PG 16 WC Computer Science, Software Engineering; Materials Science, Multidisciplinary; Optics; Imaging Science & Photographic Technology SC Computer Science; Materials Science; Optics; Imaging Science & Photographic Technology GA BS37G UT WOS:000169644800080 ER PT S AU Ray-Chaudhuri, AK Fisher, AC Gullikson, EM AF Ray-Chaudhuri, AK Fisher, AC Gullikson, EM BE Grenon, BJ Dao, GT TI Defect printability modeling of smoothed substrate defects for EUV lithography SO 20TH ANNUAL BACUS SYMPOSIUM ON PHOTOMASK TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 20th Annual BACUS Symposium on Photomask Technology CY SEP 13-15, 2000 CL MONTEREY, CA SP BACUS, SPIE DE EUV lithography; defect printability; defect smoothing; lithographic modeling AB In Extreme Ultraviolet: (EUV) lithography, sub-resolution reticle substrate defects which are overcoated during the multilayer coating process could introduce proximity phase errors. A strategy for mitigating this problem is to coat the substrate with a smoothing layer prior to ML deposition. A spherical defect will be reduced to a low aspect Gaussian bump. In order to understand the smoothing requirements necessary to render a defect non-critical, we have utilized a simplified 3-D lithographic modeling approach to study the effect of a Gaussian bump in proximity to both 70 nm 1:3 WS and 35 nm 1:3 L/S printed with a 0.1 and 0.25 numerical aperture system, respectively. The results quantify that the smoothing approach can be successfully used to render a defect non-critical by two means: 1) reducing the defect volume or 2) by reducing the slope of the Gaussian bump. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Ray-Chaudhuri, AK (reprint author), Sandia Natl Labs, MS 9409, Livermore, CA 94550 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3849-9 J9 P SOC PHOTO-OPT INS PY 2000 VL 4186 BP 781 EP 786 PG 6 WC Computer Science, Software Engineering; Materials Science, Multidisciplinary; Optics; Imaging Science & Photographic Technology SC Computer Science; Materials Science; Optics; Imaging Science & Photographic Technology GA BS37G UT WOS:000169644800086 ER PT B AU Fiorino, M AF Fiorino, M GP AMS AMS TI Prospects for an improved understanding of the low frequency variability of tropical cyclones from reanalysis SO 24TH CONFERENCE ON HURRICANES AND TROPICAL METEOROLOGY/10TH CONFERENCE ON INTERACTION OF THE SEA AND ATMOSPHERE LA English DT Proceedings Paper CT 24th Conference on Hurricanes and Tropical Meteorology/10th Conference on Interaction of the Sea and Atmosphere CY MAY 29-JUN 02, 2000 CL FT LAUDERDALE, FL SP Amer Meteorol Soc ID ASSIMILATION C1 LLNL, PCMDI, Livermore, CA 94551 USA. RP Fiorino, M (reprint author), LLNL, PCMDI, L-264,POB 808, Livermore, CA 94551 USA. RI Fiorino, Michael/N-4150-2014 OI Fiorino, Michael/0000-0002-2819-8157 NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2000 BP 49 EP 50 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BY37V UT WOS:000189132700025 ER PT S AU Gosling, JT AF Gosling, JT BE Dingus, BL Kieda, DB Salamon, MH TI Coronal mass ejections SO 26TH INTERNATIONAL COSMIC RAY CONFERENCE SE AIP Conference Proceedings LA English DT Proceedings Paper CT 26th International Cosmic Ray Conference (ICRC) CY AUG 17-25, 1999 CL SALT LAKE CITY, UT SP IUPAP, US DOE, US Natl Sci Fdn, NASA, Utah High Energy Astrophys Inst, Univ Utah, Sun Microsyst, Hamamatsu Inc, Photonis Inc, W IE NE R Plein & Baus GmbH ID HIGH HELIOGRAPHIC LATITUDES; REVERSE SHOCK PAIRS; SOLAR-WIND; MAGNETIC-FIELD; 3-DIMENSIONAL PROPAGATION; EVENTS; CLOUDS; FLARES; DRIVEN; SPEEDS AB The most dramatic changes in the solar,corona occur during coronal mass ejections, or CMEs, during which solar material is propelled outward into the heliosphere from regions in the corona not previously participating in the solar wind expansion. These ejections often produce major solar wind disturbances, targe geomagnetic storms, enhancements of moderate energy (MeV) particle fluxes and decreases in the galactic cosmic ray particle flux. This paper provides an overview of the CME phenomenon with emphasis on the CMEs themselves and how they evolve as they propagate out through the heliosphere. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Ms D466, Los Alamos, NM 87545 USA. NR 58 TC 19 Z9 19 U1 2 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-939-4 J9 AIP CONF PROC PY 2000 VL 516 BP 59 EP 79 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BQ50L UT WOS:000088536700004 ER PT S AU Little, CQ Small, DE Peters, RR Rigdon, JB AF Little, CQ Small, DE Peters, RR Rigdon, JB BE Oliver, WR TI Forensic 3D scene reconstruction SO 28TH AIPR WORKSHOP: 3D VISUALIZATION FOR DATA EXPLORATION AND DECISION MAKING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 28th AIPR Workshop CY OCT 13-15, 1999 CL WASHINGTON, D.C. SP SPIE, AIPR AB Traditionally law enforcement agencies have relied on basic measurement and imaging tools, such as tape measures and cameras, in recording a crime scene. A disadvantage of these methods is that they are slow and cumbersome. The development of a portable system that can rapidly record a crime scene with current camera imaging, 3D geometric surface maps, and contribute quantitative measurements such as accurate relative positioning of crime scene objects, would be an asset to law enforcement agents in collecting and recording significant forensic data. The purpose of this project is to develop a fieldable prototype of a fast, accurate, 3D measurement and imaging system that would support law enforcement agents to quickly document and accurately record a crime scene. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Little, CQ (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 3 U2 5 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3517-1 J9 P SOC PHOTO-OPT INS PY 2000 VL 3905 BP 67 EP 73 DI 10.1117/12.384885 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Optics SC Computer Science; Optics GA BQ31L UT WOS:000087913500008 ER PT B AU Hannum, DW Linker, KL Rhykerd, CL Parmeter, JE AF Hannum, DW Linker, KL Rhykerd, CL Parmeter, JE BE Sanson, LD TI Miniaturized explosives preconcentrators for use in man-portable explosives detection systems SO 34TH ANNUAL 2000 INTERNATIONAL CARNAHAN CONFERENCE ON SECURITY TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT 34th Annual International Carnahan Conference on Security Technology CY OCT 23-25, 2000 CL OTTAWA, CANADA SP IEEE, Lexington Sect, IEEE, Aerosp & Electron Syst Soc, Chung Shan Inst Sci & Technol, Natl Chiao-Tung Univ, G Levett & Associates AB This paper describes the function and testing of miniaturized chemical concentrating devices that are designed to enhance the capabilities of portable trace explosives detection systems, such as those based on ion mobility spectrometry (IMS). These preconcentrators are based upon a patented design first developed for use in personnel portals, in which explosive vapor and/or residue is adsorbed onto a high density metal screen, and subsequently desorbed into the detector. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hannum, DW (reprint author), Sandia Natl Labs, Dept 5848, Albuquerque, NM 87185 USA. NR 1 TC 2 Z9 2 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5966-6 PY 2000 BP 222 EP 227 DI 10.1109/CCST.2000.891191 PG 6 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BR22N UT WOS:000165903800032 ER PT B AU Kreek, SA Dardenne, Y Beckedahl, D Schmid, GJ Blair, JJ Kammeraad, J Friensehner, A AF Kreek, SA Dardenne, Y Beckedahl, D Schmid, GJ Blair, JJ Kammeraad, J Friensehner, A BE Sanson, LD TI Dramatic resolution enhancement of gamma-ray spectra acquired with cadmium-zinc-telluride detectors via a patented pulse-shape-analysis methodology SO 34TH ANNUAL 2000 INTERNATIONAL CARNAHAN CONFERENCE ON SECURITY TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT 34th Annual International Carnahan Conference on Security Technology CY OCT 23-25, 2000 CL OTTAWA, CANADA SP IEEE, Lexington Sect, IEEE, Aerosp & Electron Syst Soc, Chung Shan Inst Sci & Technol, Natl Chiao-Tung Univ, G Levett & Associates AB We are developing a technique to correct for the resolution-degrading ballistic deficit in cadmium-zinc-telluride (CZT) gamma-ray detectors using our patent-pending pulse-shape analysis methodology. The pulse-shape-analysis methodology has already been demonstrated by LLNL for application in Compton rejection (technology being licensed) and possible application to gamma-ray imaging with Ge-based systems. If the extension of our technique to CZT detectors is successful, this approach will yield a truly high-resolution CZT detector without the limitations associated with co-planar grids or other designs. Current indications are that we will achieve dramatic improvement to the resolution characteristics of CZT and greatly increase the utility of such devices for radiation detection and assessment applications. The current project status including simulations and experimental measurements are discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Kreek, SA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5966-6 PY 2000 BP 276 EP 283 DI 10.1109/CCST.2000.891200 PG 8 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BR22N UT WOS:000165903800041 ER PT B AU King, DB Zavadil, KR Ruffner, JA Luke, JR AF King, DB Zavadil, KR Ruffner, JA Luke, JR GP AIAA AIAA TI Results from the microminiature thermionic converter demonstration testing program SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut AB Research is in progress to develop microminiature thermionic converters (MTCs) using semiconductor integrated circuit (IC) fabrication methods. The use of IC techniques allows the fabrication of MTCs with an emitter to collector spacing of several microns or less and with emitter and collector materials that will have work functions ranging from 1 eV to 2 eV. Theory predicts that the small emitter to collector spacing and highly emissive low work function electrodes should allow the conversion of heat energy to relatively large electrical current densities (up to tens of Amps/cm(2)) at relatively high conversion efficiencies (15-25%). Tests of prototype MTCs have demonstrated energy conversion at several emitter temperatures. The power generated is less than expected because of less than optimal emission characteristics encountered with the low work function materials used for the first MTC prototypes. Efforts to improve electrode emission characteristics are in progress. C1 Sandia Natl Labs, Adv Nucl Concepts Dept, Albuquerque, NM 87123 USA. RP King, DB (reprint author), Sandia Natl Labs, Adv Nucl Concepts Dept, Albuquerque, NM 87123 USA. NR 3 TC 1 Z9 1 U1 0 U2 1 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 272 EP 282 PG 11 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900037 ER PT B AU Walker, A Dominic, J AF Walker, A Dominic, J GP AIAA AIAA TI Performance contracting of a parabolic trough system at the Federal Correction Institution-Phoenix SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut AB Although renewable energy technologies benefit from their "green" image, they also suffer from a perception of being expensive, hard to maintain, and unpredictable in their performance. The National Renewable Energy Laboratory (NREL) formed a partnership with a solar hot-water heating manufacturer and a Federal Correctional Institution (FCI) in Phoenix, Arizona, to demonstrate the first federal renewable energy savings performance contract (ESPC) as a solution to the problems mentioned above. A 17,040 sq. ft. solar water heating system was installed at the Phoenix FCI. The system delivered 1,161,803 kWh of heat and generated revenue of $70,025.18 during the period from March 1999 to January 2000. Under the terms of this first federal renewable ESPC, FCI Phoenix obtains all the benefits of solar water heating while transferring the first-cost and performance risks to the Energy Service Company (ESCO-in this case Industrial Solar Technology, or IST). This addressed all of the perceived risks of renewable energy. The methods used by the ESCO to address the first-cost and performance risks are the subject of this paper. C1 Natl Renewable Energy Lab, Golden, CO USA. RP Walker, A (reprint author), Natl Renewable Energy Lab, Golden, CO USA. NR 0 TC 0 Z9 0 U1 1 U2 3 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 522 EP 527 PG 6 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900069 ER PT B AU Barcomb, JD Curtner, A AF Barcomb, JD Curtner, A GP AIAA AIAA TI Multi-criteria decision-making process for buildings SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut AB The paper focuses on a process designed to facilitate two key decision points early in the building design process that are critical to a building's ultimate sustainability. As vital decisions are made during the building's design, the process and accompanying tools assist the design team in prioritizing their goals, setting performance targets, and evaluating design options to ensure that the most important issues affecting building sustainability are considered. Both the methods used and the tools required to carry out the methods are described. The process has been conceived to make the most efficient use of both the time and resources of the design team, suggesting that it will actually receive widespread use. The process is being tested within the context of the international Energy Agency Task 23, Optimization of Solar Energy Use in Large Buildings and has also been comprehensively tested by the United States Federal Energy Management Program. C1 Natl Renewable Energy Lab, Golden, CO USA. RP Barcomb, JD (reprint author), Natl Renewable Energy Lab, Golden, CO USA. NR 2 TC 0 Z9 0 U1 0 U2 2 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 528 EP 535 PG 8 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900070 ER PT B AU Roth, EP AF Roth, EP GP AIAA AIAA TI Thermal characterization of Li-ion cells using calorimetric techniques SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut ID LITHIUM INTERCALATED GRAPHITE; ACCELERATING RATE CALORIMETRY; STABILITY; BATTERIES AB The thermal stability of Li-ion cells with intercalating carbon anodes and metal oxide cathodes was measured as a function of state of charge and temperature for two advanced cell chemistries. Cells of the 18650 design with LixCoO2 cathodes (commercial Sony cells) and LixNi0.8Co0.2O2 cathodes were measured for thermal reactivity. Accelerating rate calorimetry (ARC) was used to measure cell thermal runaway as a function of state of charge (SOC), microcalorimetry was used to measure the time dependence of thermal output, and differential scanning calorimetry (DSC) was used to study the thermal reactivity of the individual components. Thermal decomposition of the anode solid electrolyte interphase (SEI) layer occurred at low temperatures and contributes to the initiation of thermal runaway. Low temperature reactions from 40 degrees C-70 degrees C were observed during the ARC runs that were SOC dependent. These reactions measured in the microcalorimeter decayed over time with power-law dependence and were highly sensitive to SOC and temperature. ARC runs of aged and cycled cells showed complete absence of these low-temperature reactions but showed abrupt exothermic spikes between 105-135 degrees C. These results suggest that during aging the anode SEI layer is decomposing from a metastable state to a stable composition that is breaking down at elevated temperatures. C1 Sandia Natl Labs, Lithium Battery R&D Dept 2521, Albuquerque, NM 87185 USA. RP Roth, EP (reprint author), Sandia Natl Labs, Lithium Battery R&D Dept 2521, POB 5800,MS0613, Albuquerque, NM 87185 USA. NR 5 TC 0 Z9 0 U1 2 U2 7 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 962 EP 967 PG 6 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900125 ER PT B AU Nagasubramanian, G AF Nagasubramanian, G GP AIAA AIAA TI Impedance studies on cathodes in Li-ion cells SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut ID LINIO2 AB Li-ion batteries have generated widespread interest as batteries of choice for a number of applications, because of their attractive energy and power densities. Although the electrical performance of the Li-ion cells at room temperature is better than that of the NiCd and NIMH cells, the performance at sub-ambient temperatures is very limited. This limitation has been attributed to the increase in cell impedance at sub-ambient temperatures. A-C impedance measurements seem to indicate that the ohmic resistance-which includes electrolyte resistance, electrodes bulk resistance, current collector and tab resistances- of the cells increases only marginally at sub-ambient temperatures. For example, the ohmic resistance of 18650 Li-ion cells is around 60 m Omega from around room temperature down to -20 degrees C and that at -40 degrees C is around 120 m Omega. However, in the same temperature regime (room temperature down to -40 degrees C) the overall cell impedance increases from nearly 0.2 Omega to 8 Omega. Most of the increase in cell impedance comes from the electrode/electrolyte interfacial impedance. We at Sandia National Laboratories and others have shown that the increase in impedance comes mostly from the cathode electrolyte interface and not from the anode electrolyte interface. The question then "where exactly the increase in cathode impedance comes from?" Whether it comes from the interfacial resistance (charge transfer + the Solid-Electrolyte- Interphase resistance) or fi om diffusion of Li+ inside the cathode. To answer the question, currently, we are investigating the impedance characteristics of the LiCoO2 and other metal oxide cathodes at different temperatures and cell voltage. The data seem to indicate that the interfacial impedance of the cathode/electrolyte interface mostly accounts for the cell impedance. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Nagasubramanian, G (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 8 TC 0 Z9 0 U1 0 U2 3 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 968 EP 975 PG 8 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900126 ER PT B AU Guidotti, RA Reinhardt, FW Dai, JX Xiao, D Reisner, D AF Guidotti, RA Reinhardt, FW Dai, JX Xiao, D Reisner, D GP AIAA AIAA TI Thermal-spayed, thin-film pyrite cathodes for thermal batteries-discharge-rate and temperature studies in single cells SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut AB Using an optimized thermal-spray process, coherent, dense deposits of pyrite (FeS2) with good adhesion were formed on 304 stainless steel substrates (current collectors). After leaching with CS, to remove residual free sulfur, these served as cathodes in Li(Si)/FeS2 thermal cells. The cells were tested over a temperature range of 450 degrees C to 550 degrees C under baseline loads of 125 and 250 mA/cm(2), to simulate conditions found in a thermal battery. Cells built with such cathodes outperformed standard cells made with pressed-powder parts. They showed lower interfacial resistance and polarization throughout discharge, with higher capacities per mass of pyrite. Post-treatment of the cathodes with Li2O coatings at levels of >7% by weight of the pyrite was found to eliminate the voltage transient normally observed for these materials. Results equivalent to those of standard lithiated catholytes were obtained in this manner. The use of plasma-sprayed cathodes allows the use of much thinner cells for thermal batteries since only enough material needs to be deposited as the capacity requirements of a given application demand. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Guidotti, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 0 Z9 0 U1 0 U2 3 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 976 EP 984 PG 9 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900127 ER PT B AU Urbina, A Paez, TL Jungst, RG AF Urbina, A Paez, TL Jungst, RG GP AIAA AIAA TI Stochastic modeling of rechargeable battery life in a photovoltaic power system SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut AB We have developed a stochastic model for the power generated by a photovoltaic (PV) power supply system that includes a rechargeable energy storage device. The ultimate objective of this work is to integrate this photovoltaic generator along with other generation sources to perform power flow calculations to estimate the reliability of different electricity grid configurations. For this reason, the photovoltaic power supply model must provide robust, efficient realizations of the photovoltaic electricity output under a variety of conditions and at different geographical locations. This has been achieved by use of a Karhunen-Loeve framework to model the solar insolation data. The capacity of the energy storage device, in this case a lead-acid battery, is represented by a deterministic model that uses an artificial neural network to estimate the reduction in capacity that occurs over time. When combined with an appropriate stochastic load model, all three elements yield a stochastic model for the photovoltaic power system. This model has been operated on the Monte Carlo principle in stand-alone mode to infer the probabilistic behavior of the system. In particular, numerical examples are shown to illustrate the use of the model to estimate battery life. By the end of one year of operation, there is a 50% probability for the test case shown that the battery will be at or below 95% of initial capacity. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Urbina, A (reprint author), Sandia Natl Labs, 9133,Mail Stop 0557, Albuquerque, NM 87185 USA. NR 13 TC 0 Z9 0 U1 1 U2 1 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 995 EP 1003 PG 9 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900129 ER PT B AU Lekov, A Lutz, J Liu, XM Whitehead, CD McMahon, JE AF Lekov, A Lutz, J Liu, XM Whitehead, CD McMahon, JE GP AIAA AIAA TI Determining benefits and costs of improved water heater efficiencies SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut AB Economic impacts on individual consumers from possible revisions to U.S. residential water heater energy-efficiency standards are examined using a lifecycle cost (LCC) analysis. LCC is the consumer's cost of purchasing and installing a water heater and operating it over its lifetime. This approach makes it possible to evaluate the economic impacts on individual consumers from the revised standards. The methodology allows an examination of groups of the population which benefit or lose from suggested efficiency standards. The results show that the economic benefits to consumers are significant. At the efficiency level examined in this paper, 35% of households with electric water heaters experience LCC savings, with an average savings of $106, while 4% show LCC losses, with an average loss of $40 compared to a pre-standard LCC average of $2,565. The remainder of the population (61%) are Largely unaffected. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lekov, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 1046 EP 1052 PG 7 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900137 ER PT B AU Furlong, R Shaltens, R AF Furlong, R Shaltens, R GP AIAA AIAA TI Technology assessment of DOE's 55-We stirling technology demonstrator convertor (TDC) SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut AB The Department of Energy (DOE), Germantown, MD and the NASA Glenn Research Center (GRC), Cleveland, OH are developing a Stirling Convertor for an advanced radioisotope power system as a potential power source for spacecraft on-board electric power for NASA deep space science missions. The Stirling Convertor is being evaluated as an alternative high efficiency power source to replace Radioisotope Thermoelectric Generators (RTGs). Stirling Technology Company (STC), Kennewick, WA, is developing the highly efficient, long life 55-We free-piston Stirling Convertor known as the Technology Demonstrator Convertor (TDC) under contract to DOE. GRC provides Stirling technology expertise under a Space Act Agreement with the DOE. Lockheed Martin Astronautics (LMA), Valley Forge, PA is the current power system integrator for the Advanced Radioisotope Power System (ARPS) Project for the DOE. JPL is responsible for the Outer Planets/Solar Probe Project for NASA. C1 US Dept Energy, Space & Defense Power Syst, Germantown, MD USA. RP Furlong, R (reprint author), US Dept Energy, Space & Defense Power Syst, Germantown, MD USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 1213 EP 1221 PG 9 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900160 ER PT B AU Guidotti, RA AF Guidotti, RA GP AIAA AIAA TI High-temperature batteries for geothermal and oil/gas borehole applications SO 35TH INTERSOCIETY ENERGY CONVERSION ENGINEERING CONFERENCE & EXHIBIT (IECEC), VOLS 1 AND 2, TECHNICAL PAPERS LA English DT Proceedings Paper CT 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) CY JUL 24-28, 2000 CL Las Vegas, NV SP Amer Inst Aeronaut & Astronaut ID SULFONE-BASED ELECTROLYTES; ELECTRODEPOSITION; ALUMINUM AB A literature survey and technical evaluation was carried out of technologies with appropriate candidates for use in geothermal borehole and, to a lesser extend, oil/gas boreholes. The various constraints that are posed by such an environment are discussed. The promise as well as the limitations of various candidate technologies are presented. Data for limited testing of a number of candidate systems are presented and the areas for additional future work are detailed. The use of low-temperature molten salts shows the most promise for such applications and includes those that are liquid at room temperature. The greatest challenges are to develop an appropriate electrochemical couple that is kinetically stable with the most promising electrolytes-both organic as well as inorganic-over the wide operating window that spans both borehole environments. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Guidotti, RA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 27 TC 4 Z9 4 U1 0 U2 2 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-375-5 PY 2000 BP 1276 EP 1286 PG 11 WC Engineering, Aerospace SC Engineering GA BQ77B UT WOS:000089466900168 ER PT S AU Bennett, JP Kwong, KS Krabbe, R Karr, C Wilson, E AF Bennett, JP Kwong, KS Krabbe, R Karr, C Wilson, E GP ISS ISS ISS TI Spent refractory reuse as a slag conditioning additive in the EAF SO 58TH ELECTRIC FURNACE CONFERENCE AND 17TH PROCESS TECHNOLOGY CONFERENCE PROCEEDINGS SE ELECTRIC FURNACE CONFERENCE - PROCEEDINGS LA English DT Proceedings Paper CT 58th Electric Furnace Conference/17th Process Technology Conference CY NOV 12-15, 2000 CL ORLANDO, FL SP Iron & Steel Soc, Elect Furnace Div, Iron & Steel Soc, Process Technol Div DE refractory; recycling; reuse; slag; foaming; steel AB Refractories removed from service in EAF applications are typically landfilled. A joint USDOE and Steel Manufacturers Association program involving industrial cooperators is evaluating spent refractory recycling/reuse. A review of current recycling practices and a review of progress towards controlling EAF slag chemistry and properties with the additions of basic spent refractories will be discussed. C1 USDOE, Albany Res Ctr, Albany, OR 97321 USA. RP Bennett, JP (reprint author), USDOE, Albany Res Ctr, 1450 Queen Ave SW, Albany, OR 97321 USA. NR 10 TC 3 Z9 3 U1 0 U2 1 PU IRON & STEEL SOCIETY PI WARRENDALE PA 186 THORN HILL RD, WARRENDALE, PA 15086-7528 USA SN 0096-0128 BN 1-886362-46-7 J9 ELECT FURN CONF PROC PY 2000 VL 17 BP 379 EP 390 PG 12 WC Engineering, Electrical & Electronic; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BS41U UT WOS:000169778200031 ER PT B AU Gunter, D Tierney, B Crowley, B Holding, M Lee, J AF Gunter, D Tierney, B Crowley, B Holding, M Lee, J GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI NetLogger: A toolkit for distributed system performance analysis SO 8TH INTERNATIONAL SYMPOSIUM ON MODELING, ANALYSIS AND SIMULATION OF COMPUTER AND TELECOMMUNICATION SYSTEMS, PROCEEDINGS LA English DT Proceedings Paper CT 8th International Symposium on Modeling, Analysis and Simulation of Computer and Telecommunication Systems CY AUG 29-SEP 01, 2000 CL SAN FRANCISCO, CA SP IEEE Comp Soc, IEEE Comp Soc, Tech Comm Simulat, IEEE Comp Soc, Tech Comm Comp Architecture, ACM SIGSIM, ACM SIGARCH, ACM SIGMETRICS, IFIP AB Diagnosis and debugging of performance problems on complex distributed systems requires end-to-end performance information at both the application and system level. We describe a methodology, called NetLogger, that enables real-time diagnosis of performance problems in such systems. The methodology includes tools for generating precision event logs, an interface to a system event-monitoring framework, and tools for visualizing the log data and real-time state of the distributed system. Low overhead is an important requirement for such tools, therefore we evaluate efficiency of the monitoring itself: The approach is novel in that it combines network, host, and application-level monitoring, providing a complete view of the entire system. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Gunter, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 9 TC 10 Z9 14 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-7695-0728-X PY 2000 BP 267 EP 273 DI 10.1109/MASCOT.2000.876548 PG 7 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic; Mathematics, Applied; Telecommunications SC Computer Science; Engineering; Mathematics; Telecommunications GA BQ83P UT WOS:000089740200031 ER PT B AU Hansen, FD AF Hansen, FD BE Geertman, RM TI From science to compliance: Geomechanics studies of the Waste Isolation Pilot Plant SO 8TH WORLD SALT SYMPOSIUM, VOLS 1 AND 2 LA English DT Proceedings Paper CT 8th World Salt Symposium CY MAY 07-11, 2000 CL THE HAGUE, NETHERLANDS SP Akzo Nobel Salt bv, European Salt Producers Assoc, Solut Min Res Inst Inc, Novem, Netherlands Agcy Energy & Environm, City, The Hague, Netherlands Minist Dev Cooperat, UNICEF, Deutag Europe bv AB Mechanical and hydrological properties of salt provide excellent bases for geological isolation of hazardous materials. Regulatory certification of the Waste Isolation Pilot Plant (WIPP) testifies to the nearly ideal characteristics of bedded salt deposits in southeast New Mexico. The WIPP history includes decades of testing and scientific investigations, which have resulted in a comprehensive understanding of salt's mechanical deformational and hydrological properties over an applicable range of stresses and temperatures. Comprehensive evaluation of salt's favorable characteristics helped demonstrate regulatory compliance and ensure isolation of radioactive waste placed in a salt geological setting. C1 Sandia Natl Labs, Carlsbad, NM 88220 USA. RP Hansen, FD (reprint author), Sandia Natl Labs, 115 N Main, Carlsbad, NM 88220 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-444-50065-0 PY 2000 BP 259 EP 264 PG 4 WC Geology; Mining & Mineral Processing SC Geology; Mining & Mineral Processing GA BQ57C UT WOS:000088786800040 ER PT S AU Gosling, JT AF Gosling, JT BE Mewaldt, RA Jokipii, JR Lee, MA Mobius, E Zurbuchen, TH TI Electron heating and acceleration at collisionless shocks in the solar wind SO ACCELERATION AND TRANSPORT OF ENERGETIC PARTICLES OBSERVED IN THE HELIOSPHERE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT ACE 2000 Symposium on Acceleration and Transport of Energetic Particles Observed in the Heliosphere CY JAN 05-08, 2000 CL INDIAN WELLS, CA SP ACE, Sci Working Team ID EARTHS BOW SHOCK; NONCOPLANAR MAGNETIC-FIELDS; ADIABATIC ENERGY CHANGE; VELOCITY DISTRIBUTIONS; PLASMA ELECTRONS; FRAME DEPENDENCE; UPSTREAM; WAVES AB This paper provides a brief synthesis of certain aspects of the electric and magnetic field structure of a collisionless shock in the solar wind and outlines how electron heating and acceleration at the shock is related to that structure. Emphasis is on measurements obtained in the vicinity of Earth's bow shock, although the results should have broad applicability to other shocks in the heliosphere. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Gosling, JT (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. NR 24 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 0094-243X BN 1-56396-951-3 J9 AIP CONF PROC PY 2000 VL 528 BP 207 EP 214 PG 8 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BQ94U UT WOS:000165073000039 ER PT B AU Burns, AR Houston, JE Carpick, RW Michalske, TA AF Burns, AR Houston, JE Carpick, RW Michalske, TA BE Mittal, KL TI Acid-base interactions at the molecular level: Adhesion and friction studies with interfacial force microscopy SO ACID-BASE INTERACTIONS: RELEVANCE TO ADHESION SCIENCE AND TECHNOLOGY, VOL 2 LA English DT Proceedings Paper CT 2nd International Symposium on Acid-Base Interactions - Relevance to Adhesion Science and Technology CY OCT 19-21, 1998 CL NEWARK, NJ SP C4 Technol Inc DE adhesion; friction; scanning probe microscopy; interfacial forces; interfacial force microscopy ID SELF-ASSEMBLED MONOLAYERS; SHEAR-FORCE; SURFACE; CONTACT; SCALE; FILMS; PROBE; GOLD AB To examine the forces of acid-base adhesion interactions at a molecular level, we have utilized the scanning probe Interfacial Force Microscope (IFM). Unlike cantilever-based atomic force microscopes, the IFM is a non-compliant, mechanically stable probe that provides a complete adhesion profile without jump-to-contact. In this way, we are able to quantitatively measure the work of adhesion and bond energies at well-defined, nanometer-scale single asperity contacts. In particular, we will discuss the displacement-controlled adhesion forces between self-assembled monolayers of functionalized alkanethiols strongly bound to a gold substrate and a similarly functionalized tip. We also discuss a method utilizing decoupled lateral and normal force sensors to simultaneously observe the onset of both friction and chemical bond formation. Measurements show that friction can, be directly attributed to bond formation and rupture well before repulsive contact. C1 Sandia Natl Labs, Surface & Interface Sci Dept, Albuquerque, NM 87185 USA. RP Burns, AR (reprint author), Sandia Natl Labs, Surface & Interface Sci Dept, Albuquerque, NM 87185 USA. NR 33 TC 0 Z9 0 U1 0 U2 1 PU VSP BV-C/O BRILL ACAD PUBL PI LEIDEN PA PO BOX 9000, 2300 PA LEIDEN, NETHERLANDS BN 90-6764-325-4 PY 2000 BP 223 EP 234 PG 12 WC Chemistry, Multidisciplinary; Engineering, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA BW57X UT WOS:000182486000009 ER PT J AU Osipiuk, J Sriram, M Mai, XH Adams, MWW Joachimiak, A AF Osipiuk, J Sriram, M Mai, XH Adams, MWW Joachimiak, A TI Cloning, expression, and crystallization of Cpn60 proteins from Thermococcus litoralis SO ACTA BIOCHIMICA POLONICA LA English DT Article DE archaea; Thermococcus litoralis; chaperonin; heat-shock protein ID ARCHAEON SULFOLOBUS-SOLFATARICUS; THERMOPHILIC ARCHAEBACTERIUM; THERMOPLASMA-ACIDOPHILUM; MOLECULAR CHAPERONE; HEAT-SHOCK; THERMOSOME; TRANSCRIPTION; SHIBATAE; SUBUNITS AB Two genes of the extreme thermophilic archaeon Thermococcus litoralis homologous to those that code for Cpn60 chaperonins were cloned and expressed in Escherichia coli. Each of the Cpn60 subunits as well as the entire Cpn60 complex crystallize in a variety of morphological forms. The best crystals diffract to 3.6 Angstrom resolution at room temperature and belong to the space group I422 with unit cell parameters a = b = 193.5 Angstrom, c = 204.2 Angstrom. C1 Argonne Natl Lab, Div Biosci, Argonne, IL 60439 USA. Univ Georgia, Dept Biochem & Mol Biol, Athens, GA 30602 USA. RP Osipiuk, J (reprint author), Argonne Natl Lab, Div Biosci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 24 TC 2 Z9 2 U1 0 U2 1 PU ACTA BIOCHIMICA POLONICA PI WARSAW PA PASTEURA 3, 02-093 WARSAW, POLAND SN 0001-527X J9 ACTA BIOCHIM POL JI Acta Biochim. Pol. PY 2000 VL 47 IS 1 BP 209 EP 214 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 300BH UT WOS:000086232600024 PM 10961695 ER PT J AU Boettinger, WJ Coriell, SR Greer, AL Karma, A Kurz, W Rappaz, M Trivedi, R AF Boettinger, WJ Coriell, SR Greer, AL Karma, A Kurz, W Rappaz, M Trivedi, R TI Solidification microstructures: Recent developments, future directions SO ACTA MATERIALIA LA English DT Review DE solidification; microstructure; theory and modeling (kinetics, transport, diffusion); casting ID PHASE-FIELD MODEL; EQUIAXED DENDRITIC SOLIDIFICATION; NI-AL SYSTEM; PRIMARY SPACING SELECTION; NICKEL-BASE SUPERALLOY; SOLUTE DIFFUSION-MODEL; ALLOY SOLIDIFICATION; RAPID SOLIDIFICATION; PERITECTIC SYSTEMS; PATTERN SELECTION AB The status of solidification science is critically evaluated and future directions of research in this technologically important area are proposed. The most important advances in solidification science and technology of the last decade are discussed: interface dynamics, phase selection, microstructure selection, peritectic growth, convection effects, multicomponent alloys, and numerical techniques. It is shown how the advent of new mathematical techniques (especially phase-field and cellular automata models) coupled with powerful computers now allows the following: modeling of complicated interface morphologies, taking into account not only steady state but also non-steady stare phenomena; considering real alloys consisting of many elements through on-line use of large thermodynamic data banks; and taking into account natural and forced convection effects. A series of open questions and future prospects are also given. It is hoped that the reader is encouraged to explore this important and highly interesting field and to add her/his contributions to an ever better understanding and modeling of microstructure development. (C) 2000 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Swiss Fed Inst Technol, Dept Mat, EPFL, CH-1015 Lausanne, Switzerland. NIST, Gaithersburg, MD 20899 USA. Univ Cambridge, Dept Mat Sci & Met, Cambridge CB2 3QZ, England. Northeastern Univ, Dept Phys, Boston, MA 02115 USA. Iowa State Univ, Ames, IA 50011 USA. US DOE, Ames Lab, Ames, IA 50011 USA. RP Kurz, W (reprint author), Swiss Fed Inst Technol, Dept Mat, EPFL, CH-1015 Lausanne, Switzerland. RI Greer, Alan Lindsay/G-1977-2011; Greer, Lindsay/E-9433-2017 NR 218 TC 378 Z9 435 U1 31 U2 268 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD JAN 1 PY 2000 VL 48 IS 1 BP 43 EP 70 DI 10.1016/S1359-6454(99)00287-6 PG 28 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 281ZN UT WOS:000085191500004 ER PT J AU Hannachi, F Korichi, A Wilson, AN Lopez-Martens, A Rejmund, M Schuck, C Vieu, C Chmel, G Georgen, A Hubel, H Rossbach, D Schonwasser, G Bergstrom, P Nyako, BM Timar, J Bazzacco, D Lunardi, S Rossi-Alvarez, C Bednarczyk, P Kintz, N Naguleswaran, S Astier, A Cullen, DM Sharpey-Schafer, JF Lauritsen, T Wadsworth, R AF Hannachi, F Korichi, A Wilson, AN Lopez-Martens, A Rejmund, M Schuck, C Vieu, C Chmel, G Georgen, A Hubel, H Rossbach, D Schonwasser, G Bergstrom, P Nyako, BM Timar, J Bazzacco, D Lunardi, S Rossi-Alvarez, C Bednarczyk, P Kintz, N Naguleswaran, S Astier, A Cullen, DM Sharpey-Schafer, JF Lauritsen, T Wadsworth, R TI Experimental evidence of octupole vibrations in the superdeformed well SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT International Symposium on Exotic Nuclear Structures (ENS 2000) CY MAY 15-20, 2000 CL DEBRECEN, HUNGARY SP Kernfis Versneller Inst DE SD band; linear polarization; octupole vibration ID EXCITATIONS; HG-190; BANDS AB An excited superdeformed (SD) band in Hg-190 has been observed to decay directly to the superdeformed yrast states. On the basis of its unusual properties, it has been proposed to be an octupole vibrational band. In this work we have firmly established the octupole vibrational character by measuring the electromagnetic nature of the transitions linking the excited to the yrast SD states. C1 Ctr Spectrometrie Nucl & Spectrometrie Masse, Orsay, France. Univ York, Dept Phys, York YO1 5DD, N Yorkshire, England. Inst Strahlen & Kernphys, Bonn, Germany. Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Nucl Res Inst, Debrecen, Hungary. Dept Fis, Padua, Italy. Ist Nazl Fis Nucl, Sez Padova, Padua, Italy. Inst Rech Subatom, Strasbourg, France. Inst Phys Nucl, Lyon, France. Univ Liverpool, Oliver Lodge Lab, Liverpool L69 3BX, Merseyside, England. Natl Accelerator Ctr, Cape Town, South Africa. Argonne Natl Lab, Argonne, IL 60439 USA. RP Hannachi, F (reprint author), Ctr Spectrometrie Nucl & Spectrometrie Masse, Orsay, France. RI Naguleswaran, Sanjeev/A-4305-2013; OI Wilson, Anna/0000-0001-6928-1689 NR 8 TC 0 Z9 0 U1 0 U2 1 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2000 VL 12 IS 2-4 BP 191 EP 194 PG 4 WC Physics, Nuclear SC Physics GA 396VW UT WOS:000166658800016 ER PT J AU Paul, ES Boston, AJ Nolan, PJ Scraggs, HC Semple, AT Stezowski, O Dorvaux, O Greenlees, PT Helariutta, K Jones, P Julin, R Juutinen, S Kankaanpaa, H Kettunen, H Muikku, M Nieminen, P Rahkila, P Starosta, K Chiara, CJ Fossan, DB Lane, GJ Sears, JM Smith, JF Devlin, M LaFosse, DR Sarantites, DG Lee, IY Macchiavelli, AO AF Paul, ES Boston, AJ Nolan, PJ Scraggs, HC Semple, AT Stezowski, O Dorvaux, O Greenlees, PT Helariutta, K Jones, P Julin, R Juutinen, S Kankaanpaa, H Kettunen, H Muikku, M Nieminen, P Rahkila, P Starosta, K Chiara, CJ Fossan, DB Lane, GJ Sears, JM Smith, JF Devlin, M LaFosse, DR Sarantites, DG Lee, IY Macchiavelli, AO TI Terminating bands in light xenon and iodine isotopes: New results for Xe-113,Xe-114 and I-111 SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT International Symposium on Exotic Nuclear Structures (ENS 2000) CY MAY 15-20, 2000 CL DEBRECEN, HUNGARY SP Kernfis Versneller Inst DE high-spin states; smooth band termination; lifetime measurement ID ROTATIONAL BANDS AB High-spin bands have been established in I-111(53) and Xe-113,114(54) that show the characteristics of smooth termination. Unlike the majority of such bands in Z approximate to 50 nuclei, which contain particle-hole excitations across the spherical Z = 50 shell gap, the new bands appear to be built on less-deformed valence-space configurations. This is supported by lifetime measurements in Xe-114. C1 Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Univ Jyvaskyla, Dept Phys, FIN-40351 Jyvaskyla, Finland. SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Lawrence Berkeley Natl Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Paul, ES (reprint author), Univ Liverpool, Oliver Lodge Lab, POB 147, Liverpool L69 7ZE, Merseyside, England. RI Devlin, Matthew/B-5089-2013 OI Devlin, Matthew/0000-0002-6948-2154 NR 3 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2000 VL 12 IS 2-4 BP 201 EP 205 PG 5 WC Physics, Nuclear SC Physics GA 396VW UT WOS:000166658800018 ER PT J AU Smith, ES AF Smith, ES TI Physics with CLAS SO ACTA PHYSICA HUNGARICA NEW SERIES-HEAVY ION PHYSICS LA English DT Article; Proceedings Paper CT 3rd Latin American Workshop on Nuclear and Heavy Ion Physics CY SEP 13-17, 1999 CL SAN ANDRES, COLOMBIA SP Univ Nacl Colombia, Natl Sci Fdn, Int Ctr Theoret Phys, Ctr Latinamericano Fis, Ctr Int Fis, Jefferson Natl Lab, Coll William & Mary, Washington Univ, Univ S Carolina DE CLAS; baryon resonances; quark model ID BARYONS AB We describe the physics program and the experimental equipment of the CEBAF Large Acceptance Spectrometer, CLAS. The spectrometer is located in Hall B, one of the three experimental areas at the Continuous Electron Beam Accelerator Facility (CEBAF) operated by the Thomas Jefferson National Accelerator Facility. We review the program to study baryon resonances to demonstrate the multi-particle detection capabilities of the CLAS detector. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Smith, ES (reprint author), Thomas Jefferson Natl Accelerator Facil, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 1219-7580 J9 ACTA PHYS HUNG NS-H JI Acta Phys. Hung. New Ser.-Heavy Ion Phys. PY 2000 VL 11 IS 3-4 BP 259 EP 268 PG 10 WC Physics, Nuclear SC Physics GA 355CR UT WOS:000089368500003 ER PT J AU Mahan, GD Bartkowiak, M AF Mahan, GD Bartkowiak, M TI Seebeck coefficient of CePd3 SO ACTA PHYSICA POLONICA A LA English DT Article; Proceedings Paper CT European Conference on Physics of Magnetism '99 CY JUN 21-25, 1999 CL POZNAN, POLAND SP Adam Mickiewicz Univ, Inst Phys, Polish Acad Sci, Inst Molec Phys ID DILUTE MAGNETIC-ALLOYS; LARGE-N EXPANSION; ELECTRONIC-STRUCTURE; KONDO RESONANCE; ANDERSON MODEL; YBAL3; PHOTOEMISSION; SCALE AB Rare earth compounds have potential applications in thermoelectric devices due to their large value of conductivity and Seebeck coefficient. CePd3 has the highest reported Seebeck coefficient (S similar to 125 mu V/K), when doped appropriately, among all rare-earth compounds. This high value is explained as a result of the placement of the cerium f(1) level. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Adam Mickiewicz Univ Poznan, Inst Phys, PL-61614 Poznan, Poland. RP Mahan, GD (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. NR 27 TC 1 Z9 1 U1 0 U2 1 PU POLISH ACAD SCIENCES INST PHYSICS PI WARSAW PA AL LOTNIKOW 32-46, 02-668 WARSAW, POLAND SN 0587-4246 J9 ACTA PHYS POL A JI Acta Phys. Pol. A PD JAN PY 2000 VL 97 IS 1 BP 37 EP 42 PG 6 WC Physics, Multidisciplinary SC Physics GA 289XQ UT WOS:000085647600005 ER PT S AU Lan, CJ Hu, PS AF Lan, CJ Hu, PS GP TRB TRB TRB TRB TI Mixed generalized linear model for estimating household trip production SO ACTIVITY PATTERN ANALYSIS AND EXPLORATION: TRAVEL BEHAVIOR ANALYSIS AND MODELING: PLANNING AND ADMINISTRATION SE TRANSPORTATION RESEARCH RECORD LA English DT Article; Proceedings Paper CT 79th Annual Meeting of the Transportation-Research-Board CY JAN 09-13, 2000 CL WASHINGTON, D.C. SP Transportat Res Board AB An innovative modeling framework to estimate household trip rates using 1995 Nationwide Personal Transportation Survey data is presented. A generalized linear model with a mixture of negative binomial probability distribution functions was developed on the basis of characteristics observed from the empirical distribution of household daily trips. This model provides a more flexible framework and a better model specification for analyzing household-specific trip production behavior. Compared with traditional least squares-based regression models, the parameter estimates from the proposed model are more efficient. Although the mean accuracies from the two modeling approaches are comparable, the mixed generalized linear model is more robust in identifying outliers due to its unsymmetric prediction bounds derived from more correct model specification. C1 Univ Miami, Dept Civil Architectural & Environm Engn, Miami, FL 33146 USA. Oak Ridge Natl Lab, Ctr Transportat Anal, Oak Ridge, TN 37831 USA. RP Lan, CJ (reprint author), Univ Miami, Dept Civil Architectural & Environm Engn, 1251 Mem Dr,325 McArthur, Miami, FL 33146 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU TRANSPORTATION RESEARCH BOARD NATL RESEARCH COUNCIL PI WASHINGTON PA 500 FIFTH ST, NW, WASHINGTON, DC 20001 USA SN 0361-1981 BN 0-309-06697-2 J9 TRANSPORT RES REC PY 2000 IS 1718 BP 61 EP 67 AR UNSP 00-1282 PG 7 WC Engineering, Civil; Transportation; Transportation Science & Technology SC Engineering; Transportation GA BU58M UT WOS:000176424900008 ER PT S AU Gavel, DT Olivier, SS Bauman, B Max, CE Macintosh, B AF Gavel, DT Olivier, SS Bauman, B Max, CE Macintosh, B BE Wizinowich, PL TI Progress with the Lick adaptive optics system SO ADAPTIVE OPTICAL SYSTEMS TECHNOLOGY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optical Systems Technology CY MAR 29-31, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc ID LASER GUIDE STAR AB Progress and results of observations with the Lick Observatory Laser Guide Star Adaptive Optics System are presented. This system is optimized for diffraction-limited imaging in the near infrared, 1-2 micron wavelength bands. We describe our development efforts in a number of component areas including, a redesign of the optical bench layout, the commissioning of a new infrared science camera, and improvements to the software and user interface. There is also an ongoing effort to characterize the system performance with both natural and laser guide stars and to fold this data into a refined system model. Such a model can be used to help plan future observations, for example, predicting the point-spread function as a function of seeing and guide star magnitude. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Gavel, DT (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 10 TC 18 Z9 18 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3632-1 J9 P SOC PHOTO-OPT INS PY 2000 VL 4007 BP 63 EP 70 DI 10.1117/12.390289 PN 1&2 PG 8 WC Astronomy & Astrophysics; Optics SC Astronomy & Astrophysics; Optics GA BQ70C UT WOS:000089218600008 ER PT S AU Johansson, EM Acton, DS An, JR Avicola, K Beeman, BV Brase, JM Carrano, CJ Gathright, J Gavel, DT Hurd, RL Lai, O Lupton, W Macintosh, BA Max, CE Olivier, SS Shelton, JC Stomski, PJ Tsubota, K Waltjen, KE Watson, JA Wizinowich, PL AF Johansson, EM Acton, DS An, JR Avicola, K Beeman, BV Brase, JM Carrano, CJ Gathright, J Gavel, DT Hurd, RL Lai, O Lupton, W Macintosh, BA Max, CE Olivier, SS Shelton, JC Stomski, PJ Tsubota, K Waltjen, KE Watson, JA Wizinowich, PL BE Wizinowich, PL TI Initial performance of the Keck AO wavefront controller system SO ADAPTIVE OPTICAL SYSTEMS TECHNOLOGY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optical Systems Technology CY MAR 29-31, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc ID TELESCOPE AB The wavefront controller for the Keck Observatory AO system consists of two separate real-time control loops: a tip-tilt control loop to remove tilt from the incoming wavefront, and a deformable mirror control loop to remove higher-order aberrations. In this paper, we describe these control loops and analyze their performance using diagnostic data acquired during the integration and testing of the AO system on the telescope. Disturbance rejection curves for the controllers are calculated from the experimental data and compared to theory. The residual wavefront errors due to control loop bandwidth are also calculated from the data, and possible improvements to the controller performance are discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Johansson, EM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 4 TC 10 Z9 10 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3632-1 J9 P SOC PHOTO-OPT INS PY 2000 VL 4007 BP 600 EP 607 DI 10.1117/12.390320 PN 1&2 PG 8 WC Astronomy & Astrophysics; Optics SC Astronomy & Astrophysics; Optics GA BQ70C UT WOS:000089218600068 ER PT S AU Max, CE Macintosh, BA Gibbard, S Gavel, DT Roe, H de Pater, I Ghez, AM Acton, S Wizinowich, PL Lai, OP AF Max, CE Macintosh, BA Gibbard, S Gavel, DT Roe, H de Pater, I Ghez, AM Acton, S Wizinowich, PL Lai, OP BE Wizinowich, PL TI Neptune and Titan observed with Keck Telescope adaptive optics SO ADAPTIVE OPTICAL SYSTEMS TECHNOLOGY, PTS 1 AND 2 SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Adaptive Optical Systems Technology CY MAR 29-31, 2000 CL MUNICH, GERMANY SP SPIE, European SO Observ, DFM Engn Inc DE adaptive optics; Neptune; Titan ID SURFACE; IMAGES AB We report on observations taken during engineering science validation time using the new adaptive optics system at the 10-m Keck II Telescope. We observed Neptune and Titan at near-infrared wavelengths. These objects are ideal for adaptive optics imaging because they are bright and small, yet have many diffraction-limited resolution elements across their disks. In addition Neptune and Titan have prominent physical features, some of which change markedly with time. We have observed infrared-bright "storms" on Neptune, and very low-albedo surface regions on Titan, Saturn's largest moon. Spatial resolution on Neptune and Titan was 0.05-0.06 and 0.04-0.05 are sec, respectively. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Max, CE (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 17 TC 3 Z9 3 U1 0 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3632-1 J9 PROC SPIE PY 2000 VL 4007 BP 803 EP 810 DI 10.1117/12.390308 PN 1&2 PG 8 WC Astronomy & Astrophysics; Optics SC Astronomy & Astrophysics; Optics GA BQ70C UT WOS:000089218600088 ER PT S AU Krupke, WF AF Krupke, WF BE Osinski, M Powell, HT Toyoda, K TI Advanced diode pumped solid state lasers (DPSSLs): Near term trends and future prospects SO ADVANCED HIGH-POWER LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced High-Power Lasers CY NOV 01-05, 1999 CL OSAKA, JAPAN SP Laser Soc Japan, SPIE, Osaka Univ, Fac Engn & ILE, ICF Forum, Inst Laser Technol, Japan Atomic Energy Res Inst, Optoelectr Ind & Technol Dev Assoc, Adv Mat Proc Inst Kinki, R&D Inst Photon Engn DE laser diode pumping; solid state laser; Nd : YAG; Yb : YAG; high power; high beam quality ID PERFORMANCE; FUSION AB The features of modern, high-power semiconductor diode laser arrays as sources for pumping high power solid state lasers are reviewed. The status and prospects for high power, high-beam quality Nd:YAG and Yb:YAG DPSSLs are examined. Developing concepts for novel high power DPSSLs are also outlined. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Krupke, WF (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 32 TC 11 Z9 11 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3487-6 J9 P SOC PHOTO-OPT INS PY 2000 VL 3889 BP 21 EP 32 DI 10.1117/12.380885 PG 12 WC Optics SC Optics GA BP93S UT WOS:000086689800003 ER PT S AU Beach, RJ Honea, EC Sutton, SB Bibeau, CM Skidmore, JA Emanuel, MA Payne, SA Avizonis, PV Monroe, RS Harris, DG AF Beach, RJ Honea, EC Sutton, SB Bibeau, CM Skidmore, JA Emanuel, MA Payne, SA Avizonis, PV Monroe, RS Harris, DG BE Osinski, M Powell, HT Toyoda, K TI High-average-power diode-pumped Yb : YAG lasers SO ADVANCED HIGH-POWER LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced High-Power Lasers CY NOV 01-05, 1999 CL OSAKA, JAPAN SP Laser Soc Japan, SPIE, Osaka Univ, Fac Engn & ILE, ICF Forum, Inst Laser Technol, Japan Atomic Energy Res Inst, Optoelectr Ind & Technol Dev Assoc, Adv Mat Proc Inst Kinki, R&D Inst Photon Engn ID OPTIMIZATION; ARRAYS AB A scaleable diode end-pumping technology for high-average-power slab and rod lasers has been under development for the past several years at Lawrence Livermore National Laboratory (LLNL). This technology has particular application to high average power Yb:YAG lasers that utilize a rod configured gain element. Previously, this rod configured approach has achieved average output powers in a single 5 cm long by 2 mm diameter Yb:YAG rod of 430 W cw and 280 W q-switched. High beam quality (M-2=2.4) q-switched operation has also been demonstrated at over 180 W of average output power(1). More recently, using a dual rod configuration consisting of two, 5 cm long by 2 mm diameter laser rods with birefringence compensation, we have achieved 1080 W of cw output with an M-2 value of 13.5 at an optical-to-optical conversion efficiency of 27.5%(2). With the same dual rod laser operated in a q-switched mode, we have also demonstrated 532 W of average power with an M-2<2.5 at 17% optical-to-optical conversion efficiency. These q-switched results were obtained at a 10 kHz repetition rate and resulted in 77 nsec pulse durations. These improved levels of operational performance have been achieved as a result of technology advancements made in several areas that will be covered in this manuscript. These enhancements to our architecture include: (1) Hollow lens ducts that enable the use of advanced cavity architectures permitting birefringence compensation and the ability to run in large aperture-filling near-diffraction-limited modes. (2) Compound laser rods with flanged-nonabsorbing-endcaps fabricated by diffusion bonding. (3) Techniques for suppressing amplified spontaneous emission (ASE) and parasitics in the polished barrel rods. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Beach, RJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-441,POB 808, Livermore, CA 94551 USA. NR 19 TC 15 Z9 15 U1 3 U2 5 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3487-6 J9 P SOC PHOTO-OPT INS PY 2000 VL 3889 BP 246 EP 260 DI 10.1117/12.380891 PG 15 WC Optics SC Optics GA BP93S UT WOS:000086689800028 ER PT S AU Benson, SV Neil, GR Bohn, C Biallas, G Douglas, D Dylla, F Fugitt, J Jordan, K Krafft, G Merminga, L Preble, J Shinn, M Siggins, T Walker, R Yunn, B AF Benson, SV Neil, GR Bohn, C Biallas, G Douglas, D Dylla, F Fugitt, J Jordan, K Krafft, G Merminga, L Preble, J Shinn, M Siggins, T Walker, R Yunn, B BE Osinski, M Powell, HT Toyoda, K TI A kilowatt average power laser for sub-picosecond materials processing SO ADVANCED HIGH-POWER LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced High-Power Lasers CY NOV 01-05, 1999 CL OSAKA, JAPAN SP Laser Soc Japan, SPIE, Osaka Univ, Fac Engn & ILE, ICF Forum, Inst Laser Technol, Japan Atomic Energy Res Inst, Optoelectr Ind & Technol Dev Assoc, Adv Mat Proc Inst Kinki, R&D Inst Photon Engn DE free-electron laser; energy recovery; picosecond pulses; laser processing ID IR DEMO FEL; JEFFERSON AB The performance of laser pulses in the sub-picosecond range for materials processing is substantially enhanced over similar fluences delivered in longer pulses. Recent advances in the development of solid state lasers have progressed significantly toward the higher average powers potentially useful for many applications. Nonetheless, prospects remain distant for multi-kilowatt sub-picosecond solid state systems such as would be required for industrial scale surface processing of metals and polymers. We present operational results from the world's first kilowatt scale ultra-fast materials processing laser. A Free Electron Laser (FEL) called the IR Demo is operational as a User Facility at Thomas Jefferson National Accelerator Facility in Newport News, Virginia, USA. In its initial operation at high average power it is capable of wavelengths in the 2 to 6 micron range and can produce similar to 0.7 ps pulses in a continuous train at similar to 75 MHz. This pulse length has been shown to be nearly optimal for deposition of energy in materials at the surface. Upgrades in the near future will extend operation beyond 10 kW CW average power in the near IR and kilowatt levels of power at wavelengths from 0.3 to 60 microns. This paper will cover the design and performance of this groundbreaking laser and operational aspects of the User Facility. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Benson, SV (reprint author), Thomas Jefferson Natl Accelerator Facil, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3487-6 J9 P SOC PHOTO-OPT INS PY 2000 VL 3889 BP 309 EP 314 DI 10.1117/12.380898 PG 6 WC Optics SC Optics GA BP93S UT WOS:000086689800034 ER PT S AU Zacharias, R Bliss, E Winters, S Sacks, R Feldman, M Grey, A Koch, J Stolz, C Toeppen, J Van Atta, L Woods, B AF Zacharias, R Bliss, E Winters, S Sacks, R Feldman, M Grey, A Koch, J Stolz, C Toeppen, J Van Atta, L Woods, B BE Osinski, M Powell, HT Toyoda, K TI Wavefront control of high-power laser beams in the National Ignition Facility (NIF) SO ADVANCED HIGH-POWER LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced High-Power Lasers CY NOV 01-05, 1999 CL OSAKA, JAPAN SP Laser Soc Japan, SPIE, Osaka Univ, Fac Engn & ILE, ICF Forum, Inst Laser Technol, Japan Atomic Energy Res Inst, Optoelectr Ind & Technol Dev Assoc, Adv Mat Proc Inst Kinki, R&D Inst Photon Engn DE wavefront control; wavefront correction; adaptive optics; high power lasers AB The use of lasers as the driver for inertial confinement fusion and weapons physics experiments is based on their ability to produce high-energy short pulses in a beam with low divergence. Indeed, the focusability of high quality laser beams far exceeds alternate technologies and is a major factor in the rationale for building high power lasers for such applications. The National Ignition Facility (NIF) is a large, 192-beam, high-power laser facility under construction at the Lawrence Livermore National Laboratory for fusion and weapons physics experiments. Its uncorrected minimum focal spot size is limited by laser system aberrations. The NIF includes a Wavefront Control System to correct these aberrations to yield a focal spot small enough for its applications. Sources of aberrations to be corrected include prompt pump-induced distortions in the laser amplifiers, previous-shot thermal distortions, beam off-axis effects, and gravity, mounting, and coating-induced optic distortions. Aberrations from gas density variations and optic-manufacturing figure errors are also partially corrected. This paper provides an overview of the NIF Wavefront Control System and describes the target spot size performance improvement it affords. It describes provisions made to accommodate the NIF's high fluence (laser beam and flashlamp), large wavefront correction range, wavefront temporal bandwidth, temperature and humidity variations, cleanliness requirements, and exception handling requirements (e.g. wavefront out-of-limits conditions). C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Zacharias, R (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 12 TC 16 Z9 16 U1 0 U2 9 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3487-6 J9 P SOC PHOTO-OPT INS PY 2000 VL 3889 BP 332 EP 343 DI 10.1117/12.380902 PG 12 WC Optics SC Optics GA BP93S UT WOS:000086689800037 ER PT S AU Honea, EC Beach, RJ Mitchell, SC Skidmore, JA Emanuel, MA Sutton, SB Payne, SA Avizonis, PV Monroe, RS Harris, DG AF Honea, EC Beach, RJ Mitchell, SC Skidmore, JA Emanuel, MA Sutton, SB Payne, SA Avizonis, PV Monroe, RS Harris, DG BE Injeyan, H Keller, U Marshall, C TI Dual-rod Yb : YAG laser for high-power and high-brightness applications SO ADVANCED SOLID STATE LASERS, PROCEEDINGS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid State Lasers CY FEB 13-16, 2000 CL DAVOS, SWITZERLAND SP Opt Soc Amer, IEEE, Lasers & Electro Opt Soc, European Phys Soc ID ND-YAG; LIMITATIONS; GENERATION AB We describe a diode-pumped Yb:YAG laser producing 1080 W cw with 27.5% optical-optical efficiency and 532 W Q-switched with M-2 =2.2 and 17% optical-optical efficiency. The laser uses two composite Yb:YAG rods separated by a 90 degree quartz rotator for bifocusing compensation. A microlensed diode array end-pumps each rod using a hollow lens duct for pump delivery. By changing resonator parameters, we can adjust the fundamental mode size and the output beam quality. Using a flattened gaussian intensity profile to calculate the modefill efficiency and clipping losses, we compare experimental data to modeled output power vs beam quality. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Honea, EC (reprint author), Lawrence Livermore Natl Lab, POB 808,L-842, Livermore, CA 94551 USA. NR 21 TC 10 Z9 10 U1 0 U2 2 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-628-1 J9 OSA TRENDS OPT PHOTO PY 2000 VL 34 BP 42 EP 47 PG 6 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BU18F UT WOS:000175262800010 ER PT S AU Nostrand, MC Page, RH Payne, SA Schunemann, PG Isaenko, LI AF Nostrand, MC Page, RH Payne, SA Schunemann, PG Isaenko, LI BE Injeyan, H Keller, U Marshall, C TI Laser demonstrations of rare-earth ions in low-phonon chloride and sulfide crystals SO ADVANCED SOLID STATE LASERS, PROCEEDINGS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid State Lasers CY FEB 13-16, 2000 CL DAVOS, SWITZERLAND SP Opt Soc Amer, IEEE, Lasers & Electro Opt Soc, European Phys Soc AB Laser results are summarized for the low-phonon hosts KPb2Cl5 and CaGa2S4. Radiative quantum efficiencies were determined in KPb2Cl5:Dy3+ directly from emission spectra in order to accurately determine its long-wavelength potential. The results indicate that room-temperature laser action should be possible to near 9 mum in this host. OCIS codes: (140.3380) Laser materials; (140.3580) Lasers, solid-state; (140.5680) Rare-earth and transition metal solid-state lasers. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Nostrand, MC (reprint author), Lawrence Livermore Natl Lab, L-482, Livermore, CA 94550 USA. RI Isaenko, Ludmila/H-7620-2013; Isaenko, Ludmila/A-5272-2014 NR 6 TC 16 Z9 17 U1 0 U2 1 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-628-1 J9 OSA TRENDS OPT PHOTO PY 2000 VL 34 BP 459 EP 463 PG 5 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BU18F UT WOS:000175262800094 ER PT B AU Miller, MK Babu, SS AF Miller, MK Babu, SS BE Chang, KM Srivastava, SK Furrer, DU Bain, KR TI Phase compositions in alloy 718: A comparison between APT/APFIM measurements and thermodynamic predictions SO ADVANCED TECHNOLOGIES FOR SUPERALLOY AFFORDABILITY LA English DT Proceedings Paper CT Symposium on Advanced Technologies for Superalloy Affordability held during the 2000 TMS Annual Meeting CY MAR 12-16, 2000 CL NASHVILLE, TN SP Mineral Met & Mat Soc AB Atom probe tomography has revealed that the individual secondary precipitates that form in Alloy 718 on low temperature annealing at 873 K are a mixture of the gamma " and gamma' phases. In addition, small gamma' precipitates were observed on the surface of the primary gamma " precipitates. The compositions of the gamma, gamma' and gamma " phases have been determined experimentally by atom probe tomography and the results have been compared to thermodynamic predictions based on the Thermocalc(TM) program. The solute partitioning is in qualitative agreement with the thermodynamic predictions but quantitatively there are some significant differences between the measured and predicted solute concentrations. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Miller, MK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Babu, Sudarsanam/D-1694-2010 OI Babu, Sudarsanam/0000-0002-3531-2579 NR 10 TC 4 Z9 5 U1 1 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-457-7 PY 2000 BP 63 EP 72 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ53J UT WOS:000088672700007 ER PT B AU Babu, SS David, SA Vitek, JM Miller, MK AF Babu, SS David, SA Vitek, JM Miller, MK BE Chang, KM Srivastava, SK Furrer, DU Bain, KR TI Precipitation of gamma ' from gamma during the weld thermal cycle: Recent results of APFIM characterization and modeling SO ADVANCED TECHNOLOGIES FOR SUPERALLOY AFFORDABILITY LA English DT Proceedings Paper CT Symposium on Advanced Technologies for Superalloy Affordability held during the 2000 TMS Annual Meeting CY MAR 12-16, 2000 CL NASHVILLE, TN SP Mineral Met & Mat Soc ID ATOM-PROBE AB Welding is important for economical reuse and reclamation of used and failed nickel-base superalloy blades. The microstructure development and the characteristics of gamma' precipitation from gamma phase during simulated weld cooling conditions were investigated with transmission electron microscopy, atom probe field ion microscopy and atom probe tomography. The number density of gamma' precipitates increased with an increase in cooling rate. Atom probe tomography of the water-quenched sample revealed both interconnected and separate gamma' precipitates within the gamma matrix. Fine scale elemental partitioning characteristics between gamma and gamma'' were measured. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Babu, SS (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI Babu, Sudarsanam/D-1694-2010 OI Babu, Sudarsanam/0000-0002-3531-2579 NR 14 TC 1 Z9 1 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-457-7 PY 2000 BP 83 EP 92 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ53J UT WOS:000088672700009 ER PT J AU Dienes, JK AF Dienes, JK TI Inferring three-dimensional crack statistics from two-dimensional data SO ADVANCES IN APPLIED MATHEMATICS LA English DT Article AB In rock mechanics it is often assumed that the number of cracks whose size exceeds c is given by the exponential N(0)e(-c/(c) over bar). It is difficult, however, to examine the cracks in a three-dimensional body to verify this exponential variation, and one is normally limited to observations on an outcropping, a cut, or a plane obtained by sectioning a sample. In this paper, we consider two mathematical problems. The direct problem is to find the distribution of the line segments in a plane section when the three-dimensional distribution of cracks is homogeneous, isotropic, and exponential. It will be shown that this distribution can be expressed by means of a Hankel function and that the distribution in a plane section is qualitatively different from the three-dimensional exponential distribution in having a peak at a finite value of segment length. It is found that the mean segment size in the plane is pi/2 times the mean crack diameter in these dimensions. This is consistent with the well-known observation that small cracks have a lower probability of being intercepted by a plane than larger cracks. The indirect problem is to infer the three-dimensional distribution of cracks from the distribution on a plane section. This problem is solved by deriving an integral equation relating the three-dimensional distribution of cracks to the distribution of line segments in a plane and showing that it can be solved for an arbitrary distribution of segments, The special case of the Hankel distribution in the plane leads to an exponential distribution in three dimensions, verifying the general solution of the indirect problem, (C) 2000 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Detonat Theory & Applicat Grp T14, Los Alamos, NM 87545 USA. RP Dienes, JK (reprint author), Univ Calif Los Alamos Natl Lab, Detonat Theory & Applicat Grp T14, POB 1663, Los Alamos, NM 87545 USA. NR 6 TC 3 Z9 3 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0196-8858 J9 ADV APPL MATH JI Adv. Appl. Math. PD JAN PY 2000 VL 24 IS 1 BP 57 EP 64 DI 10.1006/aama.1999.0674 PG 8 WC Mathematics, Applied SC Mathematics GA 289YD UT WOS:000085648800003 ER PT S AU Tanaka, H Inokuti, M AF Tanaka, H Inokuti, M BE Bederson, B Walther, H TI Plasma processing of materials and atomic, molecular, and optical physics. An introduction SO ADVANCES IN ATOMIC, MOLECULAR, AND OPTICAL PHYSICS, VOL 43 SE Advances In Atomic Molecular and Optical Physics LA English DT Review ID ELECTRON-IMPACT DISSOCIATION; DEEXCITATION CROSS-SECTIONS; SILANE PLASMA; CF4; COLLISIONS; RADICALS; SIH4; FLUOROALKANES; SPECTROSCOPY; EXCITATION C1 Sophia Univ, Fac Sci & Technol, Dept Phys, Tokyo 102, Japan. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Tanaka, H (reprint author), Sophia Univ, Fac Sci & Technol, Dept Phys, Tokyo 102, Japan. NR 37 TC 19 Z9 19 U1 1 U2 2 PU ELSEVIER ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 1049-250X BN 0-12-003843-9 J9 ADV ATOM MOL OPT PHY JI Adv. Atom. Mol. Opt. Phys. PY 2000 VL 43 BP 1 EP 17 PG 17 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA BP49S UT WOS:000085323400001 ER PT J AU Becker, K Deutsch, H Inokuti, M AF Becker, K Deutsch, H Inokuti, M TI Opportunities and challenges for atomic, molecular, and optical physics in plasma chemistry SO ADVANCES IN ATOMIC, MOLECULAR, AND OPTICAL PHYSICS, VOL 43 SE ADVANCES IN ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Review C1 Stevens Inst Technol, Dept Phys & Engn Phys, Hoboken, NJ 07030 USA. Univ Greifswald, Inst Phys, Greifswald, Germany. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Becker, K (reprint author), Stevens Inst Technol, Dept Phys & Engn Phys, Hoboken, NJ 07030 USA. NR 8 TC 5 Z9 5 U1 0 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0065-2199 J9 ADV ATOM MOL OPT PHY PY 2000 VL 43 BP 399 EP 406 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA BP49S UT WOS:000085323400012 ER PT J AU Miyabe, K Guiochon, G AF Miyabe, K Guiochon, G TI Fundamental interpretation of the peak profiles in linear reversed-phase liquid chromatography SO ADVANCES IN CHROMATOGRAPHY, VOL 40 SE ADVANCES IN CHROMATOGRAPHY LA English DT Review ID OCTADECYLSILYL-SILICA GEL; BONDED STATIONARY PHASES; MASS-TRANSFER KINETICS; SURFACE-DIFFUSION COEFFICIENT; ADSORPTION CHARACTERISTICS; CONCENTRATION-DEPENDENCE; HOMOLOGOUS SERIES; ACTIVATED CARBON; LATERAL DIFFUSION; MOBILE-PHASE C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Miyabe, K (reprint author), Toyama Univ, Fac Educ, Toyama 930, Japan. NR 126 TC 76 Z9 76 U1 0 U2 5 PU MARCEL DEKKER PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0065-2415 J9 ADV CHROMATOGR PY 2000 VL 40 BP 1 EP 113 PG 113 WC Chemistry, Analytical SC Chemistry GA BP81G UT WOS:000086275600001 ER PT B AU Spath, P Amos, W AF Spath, P Amos, W BE Padro, CEG Lau, F TI Hydrogen production from Western coal including Co-2 sequestration and coalbed methane recovery: Economics, Co-2 emissions, and energy balance SO ADVANCES IN HYDROGEN ENERGY LA English DT Proceedings Paper CT Symposium on Hydrogen Production, Storage, and Utilization CY AUG 22-26, 1999 CL NEW ORLEANS, LA SP Amer Chem Soc C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Spath, P (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46429-2 PY 2000 BP 17 EP 30 PG 14 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA BR71Z UT WOS:000167301200002 ER PT B AU Kopasz, JP Wilkenhoener, R Ahmed, S Carter, JD Krumpelt, M AF Kopasz, JP Wilkenhoener, R Ahmed, S Carter, JD Krumpelt, M BE Padro, CEG Lau, F TI Fuel flexible reforming of hydrocarbons for automotive applications SO ADVANCES IN HYDROGEN ENERGY LA English DT Proceedings Paper CT Symposium on Hydrogen Production, Storage, and Utilization CY AUG 22-26, 1999 CL NEW ORLEANS, LA SP Amer Chem Soc C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Kopasz, JP (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46429-2 PY 2000 BP 47 EP 56 PG 10 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA BR71Z UT WOS:000167301200004 ER PT B AU Czernik, S French, R Feik, C Chornet, E AF Czernik, S French, R Feik, C Chornet, E BE Padro, CEG Lau, F TI Production of hydrogen from biomass by pyrolysis/steam reforming SO ADVANCES IN HYDROGEN ENERGY LA English DT Proceedings Paper CT Symposium on Hydrogen Production, Storage, and Utilization CY AUG 22-26, 1999 CL NEW ORLEANS, LA SP Amer Chem Soc ID OILS C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Czernik, S (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 10 TC 18 Z9 18 U1 0 U2 2 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46429-2 PY 2000 BP 87 EP 91 PG 5 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA BR71Z UT WOS:000167301200007 ER PT J AU Nellist, PD Pennycook, SJ AF Nellist, PD Pennycook, SJ TI The principles and interpretation of annular dark-field Z-contrast imaging SO ADVANCES IN IMAGING AND ELECTRON PHYSICS, VOL 113 SE ADVANCES IN IMAGING AND ELECTRON PHYSICS LA English DT Review ID TRANSMISSION ELECTRON-MICROSCOPY; CRYSTAL DEFECT STRUCTURES; ATOMIC-RESOLUTION; ADF STEM; SCATTERED ELECTRONS; SIMULATED EVOLUTION; INFORMATION LIMIT; HREM IMAGES; VISIBILITY; RETRIEVAL C1 Univ Birmingham, Sch Phys & Astron, Nanoscale Phys Res Lab, Birmingham B15 2TT, W Midlands, England. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Nellist, PD (reprint author), Univ Birmingham, Sch Phys & Astron, Nanoscale Phys Res Lab, Birmingham B15 2TT, W Midlands, England. NR 86 TC 124 Z9 125 U1 5 U2 65 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0065-2539 J9 ADV IMAG ELECT PHYS PY 2000 VL 113 BP 147 EP 203 DI 10.1016/S1076-5670(00)80013-0 PG 57 WC Microscopy; Optics; Physics, Applied; Physics, Mathematical SC Microscopy; Optics; Physics GA BQ64U UT WOS:000089036400002 ER PT J AU Onuchic, JN Nymeyer, H Garcia, AE Chahine, J Socci, ND AF Onuchic, JN Nymeyer, H Garcia, AE Chahine, J Socci, ND TI The energy landscape theory of protein folding: Insights into folding mechanisms and scenarios SO ADVANCES IN PROTEIN CHEMISTRY, VOL 53 SE ADVANCES IN PROTEIN CHEMISTRY LA English DT Review ID MOLECULAR-DYNAMICS SIMULATION; MONTE-CARLO SIMULATIONS; EGG-WHITE LYSOZYME; RATE-LIMITING STEP; NUCLEATION-CONDENSATION MECHANISM; AMINO-ACID-SEQUENCES; TRANSITION-STATE; LATTICE MODEL; CYTOCHROME-C; GLOBULAR-PROTEINS C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif Los Alamos Natl Lab, Theoret Biol & Biophys Grp, Los Alamos, NM 87545 USA. Rockefeller Univ, Ctr Studies Phys & Biol, New York, NY 10021 USA. RP Onuchic, JN (reprint author), Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RI Chahine, Jorge/G-5064-2013 FU PHS HHS [T32 GN08326] NR 208 TC 178 Z9 179 U1 3 U2 17 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0065-3233 J9 ADV PROTEIN CHEM JI Adv.Protein Chem. PY 2000 VL 53 BP 87 EP 152 PG 68 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA BQ26R UT WOS:000087751900003 PM 10751944 ER PT S AU Cardinale, GF AF Cardinale, GF BE Houlihan, FM TI Pattern transfer of sub-100 nm features in polysilicon using a single layer photoresist and extreme ultraviolet lithography SO ADVANCES IN RESIST TECHNOLOGY AND PROCESSING XVII, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th Annual SPIE Conference on Advances in Resist Technology and Processing CY FEB 28-MAR 01, 2000 CL SANTA CLARA, CA SP SPIE, Semiconductor Equipment & Mat Int, Int SEMATECH DE EUV lithography; EUV photoresist; pattern transfer; single layer photoresist ID EUV 10X MICROSTEPPER; RESISTS AB Until recently, pattern transfer of 100 nm-scale features using extreme ultraviolet lithography (EUVL) was accomplished by using an intermediate hard mask material such as silicon oxide or silicon oxynitride (1). In this experiment, a single layer of deep-UV photoresist, 175 nm thick, was patterned using Sandia's 10x-Microstepper EUV imaging system. The pattern was subsequently transferred into an underlying polysilicon layer, 300 nm thick, using a reactive ion etch process. Cross-sectional and top-down scanning electron microscopy analysis was performed to evaluate the etch process and determine sidewall angle and the etch selectivity between polysilicon and the photoresist, and were found to be >85 degrees and approximately 5:1, respectively. C1 Sandia Natl Lab, Livermore, CA 94551 USA. RP Cardinale, GF (reprint author), Sandia Natl Lab, 7011 East Ave, Livermore, CA 94551 USA. NR 13 TC 2 Z9 2 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3617-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 3999 BP 413 EP 422 DI 10.1117/12.388325 PN 1&2 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BQ56Z UT WOS:000088786500040 ER PT B AU Jorgensen, JD AF Jorgensen, JD BE Yamashita, T Tanabe, K TI Key insights from structural studies of high-temperature superconductors: Is there a path to higher T(c)? SO ADVANCES IN SUPERCONDUCTIVITY XII LA English DT Proceedings Paper CT 12th International Symposium on Superconductivity (ISS 99) CY OCT 17-19, 1999 CL MORIOKA, JAPAN SP Int Superconduct Technol Ctr, Govt Iwate Prefecture, Morioka City, Ind Vitalizat Ctr Tohoku DE crystal structure; maximum T(c); doping; electronic structure; electronically-driven structural instability ID TRANSITION-TEMPERATURE; PRESSURE; PHASE AB Structural studies have allowed the development of a model for the "ideal" high-temperature superconductor. For a given compound, the maximum T(c) is traditionally achieved by using a chemical variable to adjust the carrier concentration to the optimum value. When comparing different compounds at their optimum doping, the highest T(c) is observed for compounds with flat CuO(2) planes. T(c) can also be enhanced if the charge reservoir region, or blocking layer, is metallic. In general, these three criteria cannot simultaneously be met by adjusting a single chemical/structural variable. Additionally, recent work on HgBa(2)CuO(4+x) and 123 compounds as a function of doping suggest that electronically-driven structural distortions may hinder attempts to produce higher T(c)'s by chemical substitutions. The ideal high-T(c) compound has not yet been discovered. But, in spite of these challenges, the search should continue. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Jorgensen, JD (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 18 TC 1 Z9 1 U1 0 U2 3 PU SPRINGER-VERLAG TOKYO PI TOKYO PA 37-3, HONGO 3-CHOME BONKYO-KU, TOKYO, 113, JAPAN BN 4-431-70270-9 PY 2000 BP 9 EP 14 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA BQ47A UT WOS:000088436300002 ER PT B AU Hawsey, RA Kroeger, DM Christen, DK AF Hawsey, RA Kroeger, DM Christen, DK BE Yamashita, T Tanabe, K TI Development of biaxially textured YBa2Cu3O7 coated conductors in the US SO ADVANCES IN SUPERCONDUCTIVITY XII LA English DT Proceedings Paper CT 12th International Symposium on Superconductivity (ISS 99) CY OCT 17-19, 1999 CL MORIOKA, JAPAN SP Int Superconduct Technol Ctr, Govt Iwate Prefecture, Morioka City, Ind Vitalizat Ctr Tohoku DE high temperature superconductors; YBCO; coated conductors; ion beam assisted deposition; RABiTS; biaxial texture; electron beam evaporation; sol gel; pulsed laser deposition ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; THICK-FILMS; DEPOSITION; SRTIO3 AB Two new processes have been under development since 1991 that promise a new, cost-effective way to manufacture flexible, high current density wires made from YBa2Cu3O7 (YBCO). The key is to prepare a textured substrate, or "template," on which the YBCO may be deposited as a biaxially aligned thick film. Ion beam assisted deposition (IBAD) of yttria stabilized zirconia or magnesium oxide on alloy tapes enables a final superconducting layer with grain-to-grain, in-plane alignment to within 3-5 degrees. Similar results are achieved on rolling-assisted, biaxially textured substrates (RABiTS) using a variety of oxide layers on textured nickel tapes. The performance of research lengths of prototype wires in strong magnetic fields at 65 K already exceeds that of NbTi and Nb3Sn in liquid helium. A scalable, ex-situ process for the YBCO coating has been demonstrated on both types of substrates. Consistent values of critical current density (J(c)) greater than 1 x 10(6) A/cm(2) are now obtained on RABiTS, and J(c)'s in excess of 2 x 10(6) A/cm(2) have been obtained on both substrates. A nonmagnetic variation of RABiTS (Ni-13% Cr) has also been shown to yield J(c) greater than 1.5 x 10(6) A/cm(2). Six private companies in the U.S. are scaling up YBCO coated conductors for power and physics applications. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hawsey, RA (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG TOKYO PI TOKYO PA 37-3, HONGO 3-CHOME BONKYO-KU, TOKYO, 113, JAPAN BN 4-431-70270-9 PY 2000 BP 561 EP 566 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA BQ47A UT WOS:000088436300169 ER PT B AU Suenaga, M Chiba, T Ashworth, SP Welch, DO AF Suenaga, M Chiba, T Ashworth, SP Welch, DO BE Yamashita, T Tanabe, K TI ac losses in Bi2Sr2Ca2Cu3O10/Ag tapes: What are the critical currents to be used in loss calculations? SO ADVANCES IN SUPERCONDUCTIVITY XII LA English DT Proceedings Paper CT 12th International Symposium on Superconductivity (ISS 99) CY OCT 17-19, 1999 CL MORIOKA, JAPAN SP Int Superconduct Technol Ctr, Govt Iwate Prefecture, Morioka City, Ind Vitalizat Ctr Tohoku DE ac losses; Bi2Sr2Ca2Cu3O10/Ag tapes; the Bean and the Kim models ID FIELDS AB Since Bi2Sr2Ca2Cu3O10/Ag, [Bi2223/Ag], tapes have geometrically large aspect ratios, and have highly anisotropic properties along its crystallographic directions, it is not clear to what extent the ac loss theories, which are based on the critical-state model of an isotropic superconductor, are applicable to these conductors. We report on tests of these models against magnetically measured ac losses of a Bi2223/Ag tape, in magnetic environments similar to those in power devices. It is shown that the self-field critical currents are not appropriate for calculations of the losses in either parallel or perpendicular fields to the tape face. In addition, the use of the field-dependent critical currents, such as in Kim's model, is important to understand the behavior of the losses in perpendicular applied fields. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Suenaga, M (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG TOKYO PI TOKYO PA 37-3, HONGO 3-CHOME BONKYO-KU, TOKYO, 113, JAPAN BN 4-431-70270-9 PY 2000 BP 715 EP 720 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA BQ47A UT WOS:000088436300213 ER PT B AU Hull, JR Cansiz, A AF Hull, JR Cansiz, A BE Yamashita, T Tanabe, K TI Use of thin films in high-temperature superconducting bearings SO ADVANCES IN SUPERCONDUCTIVITY XII LA English DT Proceedings Paper CT 12th International Symposium on Superconductivity (ISS 99) CY OCT 17-19, 1999 CL MORIOKA, JAPAN SP Int Superconduct Technol Ctr, Govt Iwate Prefecture, Morioka City, Ind Vitalizat Ctr Tohoku DE levitation; bearings; thin films; high-temperature superconductors; bulk YBCO ID MAGNETIC-LEVITATION; YBA2CU3O7-DELTA; STIFFNESS; FIELD; FORCE AB In a permanent magnet/high-temperature superconductor (PM/HTS) bearing, a thin-film HTS positioned above a bulk HTS has been expected to maintain the large levitation force provided by the bulk while a low rotational drag is provided by the very high current density of the film. For the low drag to be achieved, the thin film must shield the bulk from inhomogeneous magnetic fields. However, measurement of rotational drag in a PM/HTS bearing that used a combination of bulk and film HTS showed that the thin film is not effective in reducing rotational drag. Subsequent experiments, in which an AC coil was placed above the thin-film HTS and the magnetic field on the other side of the film was measured, showed that the thin film provides good shielding when the coil axis is perpendicular to the film surface but poor shielding when the coil axis is parallel to the surface. This is consistent with the lack of reduction in rotational drag being due to a horizontal magnetic moment of the permanent magnet. The poor shielding with the coil axis parallel to the film surface is attributed to the aspect ratio of the film and the three-dimensional nature of the current flow in the film for this coil orientation. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Hull, JR (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Cansiz, Ahmet/A-5885-2012 NR 15 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER-VERLAG TOKYO PI TOKYO PA 37-3, HONGO 3-CHOME BONKYO-KU, TOKYO, 113, JAPAN BN 4-431-70270-9 PY 2000 BP 779 EP 784 PG 6 WC Physics, Applied; Physics, Condensed Matter SC Physics GA BQ47A UT WOS:000088436300231 ER PT B AU Willis, JO Daney, DE Maley, MP Boenig, HJ Fleshler, S Mele, R Coletta, G Nassi, M Clem, JR AF Willis, JO Daney, DE Maley, MP Boenig, HJ Fleshler, S Mele, R Coletta, G Nassi, M Clem, JR BE Yamashita, T Tanabe, K TI Multiphase losses in HTS prototype multistrand conductors SO ADVANCES IN SUPERCONDUCTIVITY XII LA English DT Proceedings Paper CT 12th International Symposium on Superconductivity (ISS 99) CY OCT 17-19, 1999 CL MORIOKA, JAPAN SP Int Superconduct Technol Ctr, Govt Iwate Prefecture, Morioka City, Ind Vitalizat Ctr Tohoku DE ac losses; power transmission conductors; Bi-2223/Ag tapes ID AC LOSSES; CABLES AB We report on single and multiphase ac loss measurements in four-layer prototype multi-strand conductors (PMCs) wound from HTS tape. "Two phase" losses are induced with no current flowing in the PMC but with an external ac magnetic field generated by the two normal conductors arranged at the remaining corners of an equilateral triangle forming a three-phase configuration. The losses were measured over a temperature range of 65 to 76 K, a frequency range from approximate to 10 to approximate to 200 Hz, and in magnetic fields of 0 to approximate to 5 mT. Single-phase losses are purely hysteretic in nature and exhibit power law dependence of current I ranging near 3. Two-phase loss measurements reveal two loss mechanisms with different frequency dependencies: one hysteretic in nature and the second eddy-current-like. The second term saturates near or above power line frequencies. The magnitude of the two-phase losses is proportional to the current I-2.6. C1 Univ Calif Los Alamos Natl Lab, MST STC, Los Alamos, NM 87545 USA. RP Willis, JO (reprint author), Univ Calif Los Alamos Natl Lab, MST STC, MS K763, Los Alamos, NM 87545 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG TOKYO PI TOKYO PA 37-3, HONGO 3-CHOME BONKYO-KU, TOKYO, 113, JAPAN BN 4-431-70270-9 PY 2000 BP 836 EP 838 PG 3 WC Physics, Applied; Physics, Condensed Matter SC Physics GA BQ47A UT WOS:000088436300247 ER PT J AU Rightley, ML AF Rightley, ML TI Comment on "Limitations of a reduced model for the simulation of hydrogen/air combustion" SO AIAA JOURNAL LA English DT Editorial Material ID AIR DIFFUSION FLAMES; IGNITION; OXYGEN C1 Univ Calif Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. RP Rightley, ML (reprint author), Univ Calif Los Alamos Natl Lab, Div Appl Phys, POB 1663,Mail Stop F664, Los Alamos, NM 87545 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD JAN PY 2000 VL 38 IS 1 BP 188 EP 189 PG 2 WC Engineering, Aerospace SC Engineering GA 274UK UT WOS:000084783300025 ER PT J AU Wu, JZ Prausnitz, JM Firoozabadi, A AF Wu, JZ Prausnitz, JM Firoozabadi, A TI Molecular thermodynamics of asphaltene precipitation in reservoir fluids SO AICHE JOURNAL LA English DT Review ID EQUATION; STATE; PETROLEUM; LIQUIDS; EQUILIBRIUM; STABILITY; MIXTURES; OIL AB A previously described molecular-thermodynamic framework, based on colloid theory, is used to correlate experimental asphaltene-precipitation data at high-temperature and pressure conditions. In this framework, asphaltenes and resins are represented by pseudopure components, and all other components in a crude oil are presented by a continuous medium that affects van der Waals attractions among asphaltene and resin molecules. Model parameters are evaluated systematically from average properties of asphaltenes and resins in crude oils, and from dispersion-force properties of the oil medium. Given the composition of the medium, and asphaltene and resin concentrations, the molecular-thermodynamic model described here can be used to identify the onset of asphaltene precipitation, and the total amount of precipitation at the given operation conditions. Calculated results for the effects of oil composition and pressure on asphaltene precipitation are in good agreement with at least some experimental measurements for four reservoir fluids, including Texaco, Shell, Weyburn, and North-Sea crude oils. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Reservoir Engn Res Inst, Palo Alto, CA 94304 USA. RP Prausnitz, JM (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RI Firoozabadi, Abbas/C-5319-2011; Wu, Jianzhong/I-5164-2013; OI Wu, Jianzhong/0000-0002-4582-5941 NR 33 TC 63 Z9 66 U1 1 U2 14 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0001-1541 J9 AICHE J JI AICHE J. PD JAN PY 2000 VL 46 IS 1 BP 197 EP 209 DI 10.1002/aic.690460120 PG 13 WC Engineering, Chemical SC Engineering GA 276PH UT WOS:000084886200019 ER PT S AU Doddi, SR Marathe, MV Ravi, SS Taylor, DS Widmayer, P AF Doddi, SR Marathe, MV Ravi, SS Taylor, DS Widmayer, P BE Halldorsson, MM TI Approximation algorithms for clustering to minimize the sum of diameters SO ALGORITHM THEORY - SWAT 2000 SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 7th Scandinavian Workshop on Algorithm Theory (SWAT 2000) CY JUL 05-07, 2000 CL BERGEN, NORWAY SP Res Council Norway, City of Bergen AB We consider the problem of partitioning the nodes of a complete edge weighted graph into k clusters so as to minimize the sum of the diameters of the clusters. Since the problem is NP-complete, our focus is on the development of good approximation algorithms. When edge weights satisfy the triangle inequality, we present the first approximation algorithm for the problem. The approximation algorithm yields a solution that has no more than 10k clusters such that the total diameter of these clusters is within a factor O(log(n/k)) of the optimal value for Ic clusters, where n is the number of nodes in the complete graph. For any fixed Ic, we present an approximation algorithm that produces k clusters whose total diameter is at most twice the optimal value. When the distances are not required to satisfy the triangle inequality, we show that, unless P = NP, for any rho greater than or equal to 1, there is no polynomial time approximation algorithm that can provide a performance guarantee of rho even when the number of clusters is fixed at 3. Other results obtained include a polynomial time algorithm for the problem when the underlying graph is a tree with edge weights. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. SUNY Albany, Dept Comp Sci, Albany, NY 12222 USA. Univ Calif Los Angeles, Dept Comp Sci, Los Angeles, CA 90095 USA. ETH Zurich, Inst Theoret Comp Sci, CH-8092 Zurich, Switzerland. RP Doddi, SR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS B265, Los Alamos, NM 87545 USA. NR 29 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-67690-2 J9 LECT NOTES COMPUT SC PY 2000 VL 1851 BP 237 EP 250 PG 14 WC Computer Science, Theory & Methods SC Computer Science GA BR02C UT WOS:000165404300022 ER PT S AU Brumby, SP Harvey, NR Perkins, S Porter, RB Szymanski, JJ Theiler, J Bloch, JJ AF Brumby, SP Harvey, NR Perkins, S Porter, RB Szymanski, JJ Theiler, J Bloch, JJ BE Shen, SS Descour, MR TI A genetic algorithm for combining new and existing image processing tools for multispectral imagery. SO ALGORITHMS FOR MULTISPECTRAL, HYPERSPECTRAL, AND ULTRASPECTRAL IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Multispectral, Hyperspectral, and Ultraspectral Imagery VI CY APR 24-26, 2000 CL ORLANDO, FL SP SPIE DE evolutionary computation; genetic algorithms; image processing; remote sensing; multispectral imagery; hyperspectral imagery AB We describe the implementation and performance of a genetic algorithm (GA) which evolves and combines image processing tools for multispectral imagery (MSI) datasets. Existing algorithms for particular features can also be "re-tuned" and combined with the newly evolved image processing tools to rapidly produce customized feature extraction tools. First results from our software system were presented previously. We now report on work extending our system to look for a range of broad-area features in MSI datasets. These features demand an integrated spatiospectral approach, which our system is designed to use. We describe our chromosomal representation of candidate image processing algorithms, and discuss our set of image operators. Our application has been geospatial feature extraction using publicly available MSI and hyperspectral imagery (HSI). We demonstrate our system on NASA/Jet Propulsion Laboratory's Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) HSI which has been processed to simulate MSI data from the Department of Energy's Multispectral Thermal Imager (MTI) instrument. We exhibit some of our evolved algorithms, and discuss their operation and performance. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Brumby, SP (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop D436, Los Alamos, NM 87545 USA. NR 19 TC 12 Z9 12 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3675-5 J9 P SOC PHOTO-OPT INS PY 2000 VL 4049 BP 480 EP 490 DI 10.1117/12.410371 PG 11 WC Engineering, Aerospace; Mathematics, Applied; Remote Sensing; Optics SC Engineering; Mathematics; Remote Sensing; Optics GA BQ82H UT WOS:000089706600045 ER PT S AU Doerry, A Bickel, D AF Doerry, A Bickel, D BE Zelnio, EG TI A 3-D SAR approach to IFSAR processing SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VII CY APR 24-28, 2000 CL ORLANDO, FL SP SPIE DE IFSAR; interferometry; fine resolution; 3-D; polar format AB Interferometric SAR (IFSAR) can be shown to be a special case of 3-D SAR image formation. In fact, traditional IFSAR processing results in the equivalent of merely a super-resolved, under-sampled, 3-D SAR image. However, when approached as a 3-D SAR problem, a number of IFSAR properties and anomalies are easily explained. For example,IFSAR decorrelation with height is merely ordinary migration in 3-D SAR. Consequently, treating IFSAR as a 3-D SAR problem allows insight and development of proper motion compensation techniques and image formation operations to facilitate optimal height estimation. Furthermore, multiple antenna phase centers and baselines are easily incorporated into this formulation, providing essentially a sparse array in the elevation dimension. This paper shows the Polar Format image formation algorithm extended to 3 dimensions, and then proceeds to apply it to the IFSAR collection geometry. This suggests a more optimal reordering of the traditional IFSAR processing steps. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Doerry, A (reprint author), Sandia Natl Labs, POB 5800,MS 0529, Albuquerque, NM 87185 USA. NR 7 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3679-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 4053 BP 78 EP 88 DI 10.1117/12.396318 PG 3 WC Mathematics, Applied; Optics; Telecommunications SC Mathematics; Optics; Telecommunications GA BQ82J UT WOS:000089706700008 ER PT S AU Yocky, DA Jakowatz, CV AF Yocky, DA Jakowatz, CV BE Zelnio, EG TI Two-target height effects on interferometric synthetic aperture radar coherence SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VII CY APR 24-28, 2000 CL ORLANDO, FL SP SPIE DE interferometric SAR; coherence; layover ID SAR INTERFEROMETRY; TERRAIN AB Useful products generated from interferometric synthetic aperture radar (IFSAR) complex data include height measurement, coherent change detection, and classification. The IFSAR coherence is a spatial measure of complex correlation between two collects, a product of IFSAR signal processing. A tacit assumption in such IFSAR signal processing is that the terrain height is constant across an averaging box used in the process of correlating the two images. This paper presents simulations of IFSAR coherence if two targets with different heights exist in a given correlation cell, a condition in IFSAR collections produced by layover. it also includes airborne IFSAR data confirming the simulation results. The paper concludes by exploring the implications of the results on IFSAR height measurements and classification. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Yocky, DA (reprint author), Sandia Natl Labs, POB 5800,MS1207, Albuquerque, NM 87185 USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3679-8 J9 P SOC PHOTO-OPT INS PY 2000 VL 4053 BP 102 EP 108 DI 10.1117/12.396320 PG 3 WC Mathematics, Applied; Optics; Telecommunications SC Mathematics; Optics; Telecommunications GA BQ82J UT WOS:000089706700011 ER PT S AU Jin, Z Cassada, WA Cady, CM Gray, GT AF Jin, Z Cassada, WA Cady, CM Gray, GT BE Starke, EA Sanders, TH Cassada, WA TI Mechanical response of AA7075 aluminum alloy over a wide range of temperatures and strain rates SO ALUMINIUM ALLOYS: THEIR PHYSICAL AND MECHANICAL PROPERTIES, PTS 1-3 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Aluminium Alloys (ICAA7) CY APR 09-14, 2000 CL CHARLOTTESVILLE, VIRGINIA SP Univ Virginia, Light Met Ctr, Aluminium Assoc, NASA, Langley Res Ctr, Reynolds Met Co DE Al alloy 7075; hot compression; mechanical behaviour; strain rate effect; temperature effect; work hardening ID 7075 ALUMINUM; DISSOLUTION; FLOW AB The influence of temperature and strain rate on the flow stress and work hardening rate of a 7075 aluminum alloy was studied under compressive loading over the temperature range from 23 degrees C to 470 degrees C, and strain rates from 0.001 s(-1) and 2100 s(-1). While the temperature dependence of the flow stress was found to be most significant at temperatures below 300 degrees C, the strain rate dependence of the flow stress was found to be pronounced at temperatures above 23 degrees C. Concurrently, the work hardening rate decreases significantly with increasing temperature between 23 degrees C and 300 degrees C and increases slightly at higher temperatures. The minimum work hardening rate is observed to occur at temperatures between 200 degrees C and 300 degrees C and shift to higher temperatures with increasing strain rate. A negative strain rate dependence of work hardening rate was observed at 23 degrees C, although a positive strain rate dependence of work hardening rate occurs at higher temperatures. Analysis of the experimental data revealed three deformation regimes. C1 Reynolds Met Co, Corp Res & Dev, Chester, VA 23836 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Jin, Z (reprint author), Reynolds Met Co, Corp Res & Dev, 13203 N Enon Church Rd, Chester, VA 23836 USA. NR 11 TC 8 Z9 8 U1 0 U2 1 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-853-2 J9 MATER SCI FORUM PY 2000 VL 331-3 BP 527 EP 532 PN 1-3 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ58A UT WOS:000088851600072 ER PT S AU Das, SK Hayden, HW Barthold, GB AF Das, SK Hayden, HW Barthold, GB BE Starke, EA Sanders, TH Cassada, WA TI Development of non-heat-treatable automotive aluminum sheet alloys SO ALUMINIUM ALLOYS: THEIR PHYSICAL AND MECHANICAL PROPERTIES, PTS 1-3 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Aluminium Alloys (ICAA7) CY APR 09-14, 2000 CL CHARLOTTESVILLE, VIRGINIA SP Univ Virginia, Light Met Ctr, Aluminium Assoc, NASA, Langley Res Ctr, Reynolds Met Co DE automotive applications; non-heat-treatable Al sheet AB The ALCAR(TM) Consortium was created to develop low cost, non-heat treatable automotive aluminum body sheet alloys. This paper will discuss the technical and management aspects of organizing and running a horizontal consortium for competing companies to cooperate in conducting pre-competitive research and development involving the U.S. Department of Energy, national laboratories, universities and industrial consultants. A brief summary of development, casting, rolling and stamping trials will be provided. C1 ARCO Aluminum Inc, Louisville, KY USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN USA. ASME, CRTD, Washington, DC USA. RP Das, SK (reprint author), ARCO Aluminum Inc, Louisville, KY USA. NR 0 TC 1 Z9 1 U1 0 U2 2 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-853-2 J9 MATER SCI FORUM PY 2000 VL 331-3 BP 913 EP 919 PN 1-3 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ58A UT WOS:000088851600130 ER PT S AU Hutchinson, CR Fan, X Pennycook, SJ Shiflet, GJ AF Hutchinson, CR Fan, X Pennycook, SJ Shiflet, GJ BE Starke, EA Sanders, TH Cassada, WA TI On the origin of the high resistance to coarsening of Omega plates in Al-Cu-Mg-(Ag) alloys using Z-contrast microscopy SO ALUMINIUM ALLOYS: THEIR PHYSICAL AND MECHANICAL PROPERTIES, PTS 1-3 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Aluminium Alloys (ICAA7) CY APR 09-14, 2000 CL CHARLOTTESVILLE, VIRGINIA SP Univ Virginia, Light Met Ctr, Aluminium Assoc, NASA, Langley Res Ctr, Reynolds Met Co DE coarsening; interfacial segregation; ledges; precipitation; Z-contrast ID MG-AG ALLOYS; PHASE; CONCORDE AB Conventional transmission electron microscopy (CTEM) has been used to measure the thickening kinetics of Omega plates in Al-4Cu-0.3Mg-0.4Ag (wt. %) at 200 degrees C, 250 degrees C and 300 degrees C. At 200 degrees C the plates thickened at a slow rate, remaining less than 10nm in thickness after 1000h exposure. At 250 degrees C the thickening kinetics exhibited two clearly discernible regimes. The first is characterized by a relatively slow rate of plate coarsening and the second by a much enhanced rate. The transition between the two regimes occurs after similar to 300h and at a plate thickness close to 13nm. At 300 degrees C, the Omega plates thicken rapidly and thicknesses in excess of 30nm are reached within 50h. Atomic resolution Z-contrast microscopy was used to examine the Omega plate/matrix interface as a function of time and temperature to attempt to explain the observed thickening kinetics. At all times and temperatures, two atomic layers of Ag (and possibly Mg) are present at the broad faces of the Omega plates. The ends of the plates and the risers of the growth ledges appear free of segregation. At plate thicknesses less than 13nm, the density of thickening ledges is very low and for plate thickness in excess of 13nm, the density increases dramatically. The change in ledge density is thought to be associated with the transition from full coherency to semi-coherency of the Omega plate. The critical plate thickness for this transition has been experimentally determined to be close to 13nm. The high resistance of Omega plates to thickening at temperatures up to 200 degrees C may be due to the high activation energy for ledge nucleation at plate thicknesses less than 13nm. The role of Ag (and Mg) seems to be in their contribution (structural and chemical) to the interfacial energy of the Omega phase and in determining the critical plate thickness for the loss of coherency. The necessary Ag (and Mg) redistribution accompanying a migrating growth ledge is probably of secondary concern in accounting for the observed thickening kinetics. C1 Monash Univ, Dept Mat Engn, Clayton, Vic 3168, Australia. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Kentucky, Dept Chem & Mat Engn, Lexington, KY 40506 USA. Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22901 USA. RP Hutchinson, CR (reprint author), Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22903 USA. OI Hutchinson, Christopher/0000-0003-1025-4445 NR 20 TC 9 Z9 9 U1 0 U2 0 PU TRANS TECH PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-853-2 J9 MATER SCI FORUM PY 2000 VL 331-3 BP 965 EP 970 PN 1-3 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BQ58A UT WOS:000088851600138 ER PT J AU Allen, JS Damasio, H Grabowski, TJ Cole, J Frank, RJ AF Allen, JS Damasio, H Grabowski, TJ Cole, J Frank, RJ TI Gray-white volumes of the major lobes of the human cerebrum: An MRI study using an automated segmentation algorithm. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 Univ Iowa, UIHC, Dept Neurol, Iowa City, IA 52242 USA. Univ Iowa, UIHC, Dept Anthropol, Iowa City, IA 52242 USA. Univ Iowa, Dept Neurol, Coll Med, Iowa City, IA 52242 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 2000 SU 30 BP 95 EP 95 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 286RJ UT WOS:000085458900014 ER PT J AU Kwiat, PG Hardy, L AF Kwiat, PG Hardy, L TI The mystery of the quantum cakes SO AMERICAN JOURNAL OF PHYSICS LA English DT Article ID BELL INEQUALITIES; LOCAL REALISM; VIOLATION; NONLOCALITY; THEOREM; ASSUMPTIONS; PARTICLES; PHOTONS AB In an attempt to make the concept and consequences of quantum mechanical entanglement more accessible to the non-physicist, we present a simple "real-world" explanation of the proof of quantum mechanical nonlocality without the use of inequalities. (C) 2000 American Association of Physics Teachers. C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. RP Kwiat, PG (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. NR 23 TC 18 Z9 19 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD JAN PY 2000 VL 68 IS 1 BP 33 EP 36 DI 10.1119/1.19369 PG 4 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 270KU UT WOS:000084535300006 ER PT J AU Larson-Meyer, DE Newcomer, BR Hunter, GR McLean, JE Hetherington, HP Weinsier, RL AF Larson-Meyer, DE Newcomer, BR Hunter, GR McLean, JE Hetherington, HP Weinsier, RL TI Effect of weight reduction, obesity predisposition, and aerobic fitness on skeletal muscle mitochondrial function SO AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM LA English DT Article DE nuclear magnetic resonance; skeletal muscle; oxidative phosphorylation; endurance training ID MAGNETIC-RESONANCE SPECTROSCOPY; FIBER TYPE; ENERGY-METABOLISM; CAPILLARY DENSITY; PRODUCTION-RATES; P-31 MRS; EXERCISE; INSULIN; WOMEN; RECOVERY AB We used P-31 magnetic resonance spectroscopy to measure maximal mitochondrial function in 12 obesity prone women before and after diet-induced weight reduction and in 12 matched, never-obese, and 7 endurance-trained controls, Mitochondrial function was modeled after maximum-effort plantar flexion from the phosphocreatine recovery time constant (TCPCr), the ADP recovery time constant (TCADP), and the rate of change in PCr during the first 14 s of recovery (OxPhos). Weight reduction was not associated with a significant change in mitochondrial function by TCPCr, TCADP, Or OxPhos. Mitochondrial function was not different between postobese and never-obese controls by TCPCr [35.1 +/- 2.5 (SE) vs. 34.6 +/- 2.5 s], TCADP (22.9 +/- 1.8 vs. 21.2 +/- 1.8 s), or OxPhos (0.26 +/- 0.03 vs. 0.25 +/- 0.03 mM ATP/s), postobese vs. never-obese, respectively. However, TCADP was significantly faster (14.5 +/- 2.3 s), and OxPhos was significantly higher (0.38 +/- 0.04 mM ATP/s) in the endurance-trained group. These results suggest that maximal mitochondrial function is not impaired in normal-weight obesity-prone women relative to their never-obese counterparts but is increased in endurance-trained women. C1 Univ Alabama, Div Physiol & Metab, Dept Nutr Sci, Birmingham, AL 35294 USA. Univ Alabama, Dept Crit & Diagnost Care, Birmingham, AL 35294 USA. Univ Alabama, Dept Human Studies, Birmingham, AL 35294 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Larson-Meyer, DE (reprint author), Univ Alabama, Div Physiol & Metab, Dept Nutr Sci, 1675 Univ Blvd, Birmingham, AL 35205 USA. FU NCRR NIH HHS [RR 11811]; NIDDK NIH HHS [R01 DK-51684, R01 DK-49779] NR 37 TC 15 Z9 15 U1 0 U2 1 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0193-1849 J9 AM J PHYSIOL-ENDOC M JI Am. J. Physiol.-Endocrinol. Metab. PD JAN PY 2000 VL 278 IS 1 BP E153 EP E161 PG 9 WC Endocrinology & Metabolism; Physiology SC Endocrinology & Metabolism; Physiology GA 273ZD UT WOS:000084738500020 PM 10644550 ER PT J AU Volkow, ND Logan, J Fowler, JS Wang, GJ Gur, RC Wong, C Felder, C Gatley, SJ Ding, YS Hitzemann, R Pappas, N AF Volkow, ND Logan, J Fowler, JS Wang, GJ Gur, RC Wong, C Felder, C Gatley, SJ Ding, YS Hitzemann, R Pappas, N TI Association between age-related decline in brain dopamine activity and impairment in frontal and cingulate metabolism SO AMERICAN JOURNAL OF PSYCHIATRY LA English DT Article ID CEREBRAL BLOOD-FLOW; COGNITIVE ACTIVATION; PREFRONTAL CORTEX; C-11 RACLOPRIDE; D-2 RECEPTORS; SCHIZOPHRENIA; BINDING; SYSTEM; PET; MODULATION AB Objective: Despite the well-documented loss of brain dopamine activity with age, little is known about its functional consequences in healthy individuals. This study investigates the relationship between measures of brain dopamine D-2 receptors (molecules that transmit dopamine signals) and regional brain glucose metabolism (a marker of brain function) in healthy individuals. Method: Thirty-seven healthy volunteers aged 24-86 years underwent positron emission tomography scans after injection of [C-11]raclopride to assess dopamine D-2 receptors and [(18)]fluorodeoxyglucose to assess regional brain glucose metabolism. Two methods used to assess the correlations between metabolism and dopamine D-2 receptors-pixel-by-pixel correlations and correlations in preselected regions of interest-were then compared. Results: D-2 receptors as well as frontal and cingulate metabolism declined with age. Regardless of the method used, significant correlations between metabolism and D-2 receptors were found in the frontal cortex (Brodmann's areas 6, 7, 8, 9, 10, 11, 44, 45, 47), anterior cingulate gyrus (areas 24, 32), temporal cortex (area 21), and caudate. These correlations remained significant after removing age effects (partial correlation). Conclusions: These results provide the first link between age-related declines in brain dopamine activity and frontal and cingulate metabolism, which supports the need to investigate the therapeutic utility of interventions that enhance dopamine function in the elderly. The fact that correlations remained significant after removing age effects suggests that dopamine may influence frontal, cingulate, and temporal metabolism regardless of age. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. Univ Penn, Sch Med, Brain Behav Lab, Philadelphia, PA 19104 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. FU NIDA NIH HHS [DA-06891] NR 28 TC 174 Z9 177 U1 1 U2 3 PU AMER PSYCHIATRIC PRESS, INC PI WASHINGTON PA 1400 K ST, N W, STE 1101, WASHINGTON, DC 20005 USA SN 0002-953X J9 AM J PSYCHIAT JI Am. J. Psychiat. PD JAN PY 2000 VL 157 IS 1 BP 75 EP 80 PG 6 WC Psychiatry SC Psychiatry GA 270WJ UT WOS:000084559900012 PM 10618016 ER PT J AU Hanlin, HG Martin, FD Wike, LD Bennett, SH AF Hanlin, HG Martin, FD Wike, LD Bennett, SH TI Terrestrial activity, abundance and species richness of amphibians in managed forests in South Carolina SO AMERICAN MIDLAND NATURALIST LA English DT Article ID POPULATIONS; ACIDIFICATION; SALAMANDERS AB We determined the relative abundance, days of surface activity and indices of species diversity, evenness and richness for amphibians inhabiting three differently managed forests surrounding a Carolina lay in South Carolina following restoration, We collected animals daily for 3 y (Oct. 1993-Sept. 1996) using drift fences with pitfall traps in three forest types: loblolly pine (Pinus taeda), slash pine (P. elliotta) and mixed hardwoods (predominantly oak, Quercus spp. and hickory, Carya spp.). Captured animals were marked and recaptures were recorded but not included in statistical analyses, except in our evaluation of activity. We compared results to those of a more limited study conducted before restoration. Amphibians were significantly more numerous and more active in the mixed hardwood forest than in the pine forest types. However, the hardwood forest had the lowest species diversity in 2 of the 3 y of the study. The slash pine habitat had the highest diversity in all 3 y and for the 3, combined. Because the evenness index (J') values differ in step with the species diversity index (H') it appears that the evenness component of diversity, rather than the richness component, is what is determining H' variation. A summer subset of these data and summer data from an earlier study of 1977-1978 is in marked contrast with yearlong patterns. For our summer data each forest type had the highest H' value in one of the years of the study and again the J' values parallel the differences in H'. Large numbers of southern toads (Bufo terrestris) reduced evenness, and therefore species diversity, for all three habitats particularly the mixed hardwoods where this species was especially abundant. Proportionally lower numbers of B. terrestris in the summer samples increased J' and H' indices. Overall lower abundance and H' values in the summers of 1994-1996, compared with 1977-1978 may be the result of habitat alteration during the restoration of the Carolina bay. C1 Univ S Carolina, Dept Biol & Geol, Aiken, SC 29801 USA. Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Univ S Carolina, Dept Biol & Geol, Aiken, SC 29801 USA. EM hughh@aiken.sc.edu NR 45 TC 18 Z9 22 U1 1 U2 8 PU AMER MIDLAND NATURALIST PI NOTRE DAME PA UNIV NOTRE DAME, BOX 369, ROOM 295 GLSC, NOTRE DAME, IN 46556 USA SN 0003-0031 EI 1938-4238 J9 AM MIDL NAT JI Am. Midl. Nat. PD JAN PY 2000 VL 143 IS 1 BP 70 EP 83 DI 10.1674/0003-0031(2000)143[0070:TAAASR]2.0.CO;2 PG 14 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 273CW UT WOS:000084690600006 ER PT J AU Kroh, GC White, JD Heath, SK Pinder, JE AF Kroh, GC White, JD Heath, SK Pinder, JE TI Colonization of a volcanic mudflow by an upper montane coniferous forest at Lassen Volcanic National Park, California SO AMERICAN MIDLAND NATURALIST LA English DT Article ID MOUNT-ST-HELENS; PRIMARY SUCCESSION; PLANT SUCCESSION; SEEDLING ESTABLISHMENT; RED FIR; WASHINGTON; ENVIRONMENT; VEGETATION; RECOVERY; ERUPTION AB Colonization of a relatively undisturbed 1915 debris flow by art upper montane coniferous forest was examined in Lassen Volcanic National Park in northern California in 1987. Selenty 100-m(2) circular plots were arranged in four transects across the flow and sam pled to measure tree densities, heigths, basal areas and ages. The composition of the forest changed it from a mixture of Abies magnifica, Pinus monticola and P. contorta on steep slopes to a forest dominated by P. contorta on shallow slopes. This pattern is typical for these terrains at the 2000-m elevations of the flow. Age data and historical photographs indicated little successful colonization before thr late 1930s and peal; colonization rates about 1955. Height growth has generally been slow with most trees being >20-y-old but <2-m tall; however, some individuals, including some recent colonizers, have shown rapid growth. This variation among individuals suggests (1) that the earliest colonizers are not necessarily those which will eventually dominate the forest and (2) that opportunities to invade and occupy the canopy mat extend for 30 y after the first successful colonization. C1 Texas Christian Univ, Dept Biol, Ft Worth, TX 76129 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Kroh, GC (reprint author), Texas Christian Univ, Dept Biol, Ft Worth, TX 76129 USA. NR 61 TC 8 Z9 8 U1 3 U2 3 PU AMER MIDLAND NATURALIST PI NOTRE DAME PA UNIV NOTRE DAME, BOX 369, ROOM 295 GLSC, NOTRE DAME, IN 46556 USA SN 0003-0031 J9 AM MIDL NAT JI Am. Midl. Nat. PD JAN PY 2000 VL 143 IS 1 BP 126 EP 140 DI 10.1674/0003-0031(2000)143[0126:COAVMB]2.0.CO;2 PG 15 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 273CW UT WOS:000084690600010 ER PT J AU Cheah, SF Brown, GE Parks, GA AF Cheah, SF Brown, GE Parks, GA TI XAFS study of Cu model compounds and Cu2+ sorption products on amorphous SiO2, gamma-Al2O3, and anatase SO AMERICAN MINERALOGIST LA English DT Article ID X-RAY-ABSORPTION; FINE-STRUCTURE; MULTIPLE-SCATTERING; SURFACE; SPECTROSCOPY; COMPLEXES; CU(II); SILICA; ADSORPTION; HYDROXIDE AB The primary objective of this study is to determine the effect of substrate type on the coordination environments of Cu2+ adsorbed on amorphous SiO2, gamma-Al2O,, and anatase at a surface coverage of approximately 1 mu mol/m(2). We also collected X-ray absorption fine structure (XAFS) data for several Cu2+-containing model compounds, including tenorite ((CuO)-Cu-VI), spertiniite [Cu-VI(OH)(2)], dioptase ((CuSiO2)-Cu-VI. H2O), shattuckite [Cu-VI(5)(SiO3)(4)(OH)(2)], chrysocolla [(VI)(Cu,Al)(2)H2Si2O5 (OH)(4). nH(2)O], and Cu2+ acetate monohydrate [Cu-VI(CH3CO2)(2). H2O], for comparison with the sorption sample data. Detailed analysis of these model compounds indicates that the bonding of second neighbors surrounding a central Cu absorber determines whether these second neighbors can be detected by XAFS. The XAFS results of Cu2+ sorption samples are consistent with the presence of Jahn-Teller distorted Cu2+(O,OH)(6) octahedra, with four equatorial Cu-O bonds (1.95 Angstrom) and two longer axial bonds; the axial Cu-O bonds are difficult to characterize quantitatively by XAFS spectroscopy. Cu2+ sorbed on amorphous SiO2 was found to have Cu second and third neighbors at 2.95 Angstrom, 3.30 Angstrom, and 5.72 Angstrom, but no Cu-Si correlation was detected for these sorption products associated with amorphous SiO2. Based on XAFS and wet chemical results, it seems Likely that a Cu(OH), precipitate has formed in the Cu2+/amorphous SiO2 system. Cu2+ sorbed on gamma-Al2O3 is present as a mixture of monomeric, dimeric, and perhaps a small number of oligomeric hydroxo-bridged Cu(O,OH)(6) species with a Cu-Cu distance of approximately 2.95 K. Sorbed Cu2+ on anatase is present predominantly as hydroxo-bridged Cu dimers. At similar sorption densities, Cu2+ cluster sizes on amorphous SiO2 are significantly larger than those on gamma-Al2O, or anatase, indicating that the substrate has an important effect on the type of Cu2+ sorption complex or precipitates formed. C1 Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Cheah, SF (reprint author), Univ Calif Berkeley, Div Ecosyst Sci, ESPM, Hilgard Hall 3110, Berkeley, CA 94720 USA. NR 44 TC 44 Z9 45 U1 1 U2 9 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1015 EIGHTEENTH ST, NW SUITE 601, WASHINGTON, DC 20036 USA SN 0003-004X J9 AM MINERAL JI Am. Miner. PD JAN PY 2000 VL 85 IS 1 BP 118 EP 132 PG 15 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 273NP UT WOS:000084714000013 ER PT J AU Fisler, DK Gale, JD Cygan, RT AF Fisler, DK Gale, JD Cygan, RT TI A shell model for the simulation of rhombohedral carbonate minerals and their point defects SO AMERICAN MINERALOGIST LA English DT Article ID CRYSTAL-STRUCTURE; CALCITE; ARAGONITE; REFINEMENT; MAGNESITE; DOLOMITE AB The electronic polarization of oxygen ions has been explicitly incorporated in a shell model to better simulate the structure of calcite and related rhombohedral carbonate minerals. Pair-potentials for Ca2+ ions and C and O comprising the carbonate molecular ion were simultaneously fitted to experimental lattice, elastic, dielectric, and vibrational data for calcite, and the structure and elastic properties of aragonite. The resulting potential parameters for the CO32- group were then transferred to models for the structures and bulk moduli of the carbonate minerals incorporating Mn, Fe, Mg, Ni, Zn, Co, Cd, and thus a fully consistent set of interaction parameters for calculating the properties of the carbonate minerals was obtained. Defect energies for doping the divalent cations into the calcite structure, and for calcium and carbonate ion vacancies were calculated. In addition, various disorder types for dolomite, including anti-site defects, stacking defects, and the energy related to increasing the Ca/Mg ratio in the dolomite structure were simulated. The theoretical enthalpy for dolomite ordering (34.3 kJ/mol) compares very well with experimental measurements. C1 Sandia Natl Labs, Dept Geochem, Albuquerque, NM 87185 USA. Univ London Imperial Coll Sci Technol & Med, Dept Chem, London SW7 2AY, England. RP Fisler, DK (reprint author), Johns Manville Tech Ctr, 10100 W Ute Ave,POB 625005, Littleton, CO 80162 USA. RI Gale, Julian/B-7987-2009 OI Gale, Julian/0000-0001-9587-9457 NR 33 TC 65 Z9 65 U1 1 U2 19 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1015 EIGHTEENTH ST, NW SUITE 601, WASHINGTON, DC 20036 USA SN 0003-004X J9 AM MINERAL JI Am. Miner. PD JAN PY 2000 VL 85 IS 1 BP 217 EP 224 PG 8 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 273NP UT WOS:000084714000021 ER PT J AU Panofsky, WKH AF Panofsky, WKH TI How much free speech for scientists? SO AMERICAN SCIENTIST LA English DT Article C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Panofsky, WKH (reprint author), Stanford Linear Accelerator Ctr, POB 4349, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SIGMA XI-SCI RES SOC PI RES TRIANGLE PK PA PO BOX 13975, RES TRIANGLE PK, NC 27709 USA SN 0003-0996 J9 AM SCI JI Am. Scientist PD JAN-FEB PY 2000 VL 88 IS 1 BP 6 EP 8 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 264CB UT WOS:000084161500006 ER PT S AU Geohegan, DB Puretzky, AA Fan, X Guillorn, MA Simpson, ML Merkulov, VI Pennycook, SJ AF Geohegan, DB Puretzky, AA Fan, X Guillorn, MA Simpson, ML Merkulov, VI Pennycook, SJ BE Sullivan, JP Robertson, J Zhou, O Allen, TB Coll, BF TI Mechanisms of single-wall carbon nanotube growth by the laser vaporization technique: In situ imaging and spectroscopy SO AMORPHOUS AND NANOSTRUCTURED CARBON SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Amorphous and Nanostructured Carbon at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID ABLATION PLUME; LARGE-SCALE; KRF-LASER; BACKGROUND GASES; DYNAMICS; PYROLYSIS; CHEMISTRY; EMISSION; GRAPHITE AB Single-wall carbon nanotubes are formed by Nd:YAG laser vaporization of a graphite/(1 at. % Ni, I at. % Co) target into flowing argon (500 Torr) within a quartz tube furnace (1000 degrees C). Here, this process is investigated for the first time with time-resolved laser-induced luminescence imaging and spectroscopy of Co atoms, C-2 and C-3 molecules, and clusters. These measurements under actual synthesis conditions show that the plume of vaporized material is segregated and confined within a vortex ring which maintains a similar to 1 cm(3) volume for several seconds. Using time-resolved spectroscopy and spectroscopic imaging, the time for conversion of atomic and molecular species to clusters was measured for both carbon (200 mu s) and cobalt (2 ms). This rapid conversion of carbon to nanoparticles, combined with transmission electron microscopy analysis of the collected deposits, indicate that nanotube growth occurs during several seconds of time from a feedstock of mixed nanoparticles in the gas-suspended plume. Using these in situ diagnostics to adjust the time spent by the plume within the high-temperature zone, single-walled nanotubes of controlled length were grown at an estimated rate of 0.2 mu m/s. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Geohegan, DB (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Simpson, Michael/A-8410-2011; Puretzky, Alexander/B-5567-2016; Geohegan, David/D-3599-2013 OI Simpson, Michael/0000-0002-3933-3457; Puretzky, Alexander/0000-0002-9996-4429; Geohegan, David/0000-0003-0273-3139 NR 37 TC 0 Z9 0 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-501-3 J9 MATER RES SOC SYMP P PY 2000 VL 593 BP 3 EP 14 PG 12 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BQ70Z UT WOS:000089239300001 ER PT S AU Fan, X Dickey, EC Eklund, P Williams, K Grigorian, L Puretzky, A Geohegan, D Buczko, R Pantelides, ST Pennycook, SJ AF Fan, X Dickey, EC Eklund, P Williams, K Grigorian, L Puretzky, A Geohegan, D Buczko, R Pantelides, ST Pennycook, SJ BE Sullivan, JP Robertson, J Zhou, O Allen, TB Coll, BF TI Direct observation of intercalant and catalyst particle in single wall carbon nanotubes SO AMORPHOUS AND NANOSTRUCTURED CARBON SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Amorphous and Nanostructured Carbon at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID BUNDLES AB The Z-contrast scanning transmission electron microscopy (STEM) imaging technique has been used to study dopant atoms and catalyst particles in single wall carbon nanotubes (SWNT). Iodine and bromine have been doped respectively in arc-grown SWNTs. We have directly observed the dopant sites and distributions. Both dopants appear to be incorporated linearly within the SWNT bundles. SWNT were also grown by pulsed laser ablation with mixed Ni and Co catalyst, and the size and distribution of catalytic particles was studied. By using Z-contrast imaging, we found that the size distribution of the catalyst particles varied over a large range, but even the smallest were larger than the diameter of an individual SWNT. Furthermore, electron energy loss spectroscopy (EELS) is used to determine the composition of individual nano-catalyst particles, and were found to consist of a uniform alloy of Co and Ni. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Fan, X (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Dickey, Elizabeth/A-3368-2011; Puretzky, Alexander/B-5567-2016; Geohegan, David/D-3599-2013 OI Dickey, Elizabeth/0000-0003-4005-7872; Puretzky, Alexander/0000-0002-9996-4429; Geohegan, David/0000-0003-0273-3139 NR 12 TC 2 Z9 2 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-501-3 J9 MATER RES SOC SYMP P PY 2000 VL 593 BP 129 EP 134 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BQ70Z UT WOS:000089239300020 ER PT S AU Merkulov, VI Lowndes, DH Baylor, LR AF Merkulov, VI Lowndes, DH Baylor, LR BE Sullivan, JP Robertson, J Zhou, O Allen, TB Coll, BF TI Field emission and nanostructure of carbon films SO AMORPHOUS AND NANOSTRUCTURED CARBON SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT Symposium on Amorphous and Nanostructured Carbon at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID TETRAHEDRAL AMORPHOUS-CARBON; DIAMOND AB The results of field emission measurements of various forms of carbon films are reported. It is shown that the films' nanostructure is a crucial factor determining the field emission properties. In particular, smooth, pulsed-laser deposited amorphous carbon films with both high and low sp3 contents are poor field emitters. This is similar to the results obtained for smooth nanocrystalline, sp(2) - bonded carbon films. In contrast, carbon films prepared by hot-filament chemical vapor deposition (HF-CVD) exhibit very good field emission properties, including low emission turn-on fields, high emission site density, and excellent durability. HF-CVD carbon films were found to be predominantly sp(2)-bonded. However, surface morphology studies show that these films are thoroughly nanostructured, which is believed to be responsible for their promising field emission properties. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Merkulov, VI (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM merkulov@solid.ssd.ornl.gov NR 17 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-501-3 J9 MATER RES SOC SYMP P PY 2000 VL 593 BP 221 EP 226 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BQ70Z UT WOS:000089239300034 ER PT S AU Hakovirta, M Lee, DH He, XM Nastasi, M AF Hakovirta, M Lee, DH He, XM Nastasi, M BE Sullivan, JP Robertson, J Zhou, O Allen, TB Coll, BF TI Fluorinated diamond-like carbon films produced by plasma immersion ion processing technique SO AMORPHOUS AND NANOSTRUCTURED CARBON SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Amorphous and Nanostructured Carbon at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID OPTICAL-PROPERTIES; IMPLANTATION; COATINGS; DEPOSITION AB Fluorinated diamond-like carbon (F-DLC) coatings were deposited on polished silicon substrates with plasma immersion ion processing (PIIP) technique. In the PIIP technique, pulsed glow discharge plasma from a mixture of acetylane and hexafluoroethane gases was used. Contact angle measurements were performed in order to see the un-wetting properties of the coatings. The film composition was measured with Rutherford Backscattering Spectroscopy (RBS) and Elastic Recoil Detection Analysis (ERDA) and the hardness was measured with a Nanoindenter(R) II. The results clearly show that the un-wetting properties and hardness are strongly dependent on the fluorine incorporation in the F-DLC coatings. With optimized gas ratio of acetylane and hexafluoroethane gases, a combination of extremely good un-wetting properties and high hardness was achieved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hakovirta, M (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 2 Z9 2 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-501-3 J9 MATER RES SOC SYMP P PY 2000 VL 593 BP 285 EP 290 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BQ70Z UT WOS:000089239300044 ER PT S AU LaVan, DA Hohlfelder, RJ Sullivan, JP Friedmann, TA Mitchell, M Ashby, CIH AF LaVan, DA Hohlfelder, RJ Sullivan, JP Friedmann, TA Mitchell, M Ashby, CIH BE Sullivan, JP Robertson, J Zhou, O Allen, TB Coll, BF TI Tensile properties of amorphous diamond films SO AMORPHOUS AND NANOSTRUCTURED CARBON SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Amorphous and Nanostructured Carbon at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID POLYSILICON; STRENGTH; MODULUS; HARDNESS; CARBON AB Amorphous diamond is a new material for surface micromachined microelectromechanical systems (MEMS) and sensors. Its strength and modulus was tested in uniaxial tension by pulling laterally on a specially designed sample with a flat tipped diamond in a nanoindenter. Several sample designs were attempted. Of those, only the single layer specimen with a I by 2 mu m gage cross section and a fixed end rigidly attached to the substrate vv as successful. Tensile load was calculated by resolving the measured lateral and normal forces into the applied tensile force and frictional losses. Displacement was corrected for machine compliance using the differential stiffness method. Post-mortem examination of the samples was performed to document the failure mode. The load-displacement data from those samples that failed in the gage section was converted to stress-strain curves using carefully measured gage cross section dimensions. Mean fracture strength was found to be 8.5 +/- 1.4 GPa and the modulus was 831 +/- 94 GPa. Tensile results are compared to hardness and modulus measurements made using a nanoindenter. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP LaVan, DA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI LaVan, David/C-3943-2012 OI LaVan, David/0000-0002-1952-0028 NR 13 TC 1 Z9 1 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-501-3 J9 MATER RES SOC SYMP P PY 2000 VL 593 BP 465 EP 470 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BQ70Z UT WOS:000089239300072 ER PT S AU Sternberg, M Zapol, P Frauenheim, T Gruen, DM Curtiss, LA AF Sternberg, M Zapol, P Frauenheim, T Gruen, DM Curtiss, LA BE Sullivan, JP Robertson, J Zhou, O Allen, TB Coll, BF TI Molecular dynamics simulation of impurities in nanocrystalline diamond grain boundaries SO AMORPHOUS AND NANOSTRUCTURED CARBON SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Amorphous and Nanostructured Carbon at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID CARBON AB Nanocrystalline diamond films grown on Si substrates at 800 degrees C from hydrogen-poor ;plasmas have a number of highly desirable mechanical and electronic properties. Impurities were found by SIMS measurements to be uniformly distributed throughout the thickness of the films at a level of 10(17) - 10(18) cm(-3). It is likely that the impurities are located at the grain boundaries, which play a crucial role in controlling important characteristics of the films, such as electrical conductivity and electron emission. Density-functional based tight-binding (DFTB) molecular dynamics simulations were performed for diamond high-energy high-angle (100) twist grain boundaries with impurities such as N, Si and H. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Sternberg, M (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Zapol, Peter/G-1810-2012; Frauenheim, Thomas/C-5653-2015 OI Zapol, Peter/0000-0003-0570-9169; Frauenheim, Thomas/0000-0002-3073-0616 NR 6 TC 4 Z9 4 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-501-3 J9 MATER RES SOC SYMP P PY 2000 VL 593 BP 483 EP 487 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BQ70Z UT WOS:000089239300075 ER PT S AU Jankowski, A Ramsey, P McKernan, M Morse, J AF Jankowski, A Ramsey, P McKernan, M Morse, J BE Sullivan, JP Robertson, J Zhou, O Allen, TB Coll, BF TI Nanocrystalline and hard, boron-alloyed Be coatings SO AMORPHOUS AND NANOSTRUCTURED CARBON SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Amorphous and Nanostructured Carbon at the 1999 MRS Fall Meeting CY NOV 29-DEC 02, 1999 CL BOSTON, MA SP Mat Res Soc ID NITRIDE; IMPLANTATION AB Boron-alloy coatings can be formed by sputtering compound targets, through co-deposition with other elemental targets, by utilizing reactive gas mixtures, and/or by post-deposition implantation. Specific to this study, boron-alloy coatings are assessed with respect to composition as deposited by co-sputtering boron and beryllium. Transmission electron microscope (TEM), bright-field images with selected area diffraction are used to reveal the microstructure and phase. Refinement in grain size to the nanoscale occurs through boron addition as well as transition metal impurities. An increase in coating hardness with boron addition is measured using nanoindentation. Scanning electron microscope (SEM), secondary electron images reveal the surface morphology variations for thick coatings that occur with boron addition as measured using energy dispersive spectrometry (EDS). The phase formed in boron-alloyed beryllium coating is found to be dependent on both coating composition and the sputter deposition conditions. It is concluded that the geometry of the deposition sources with the configuration of the substrate effect the coating composition, microstructure, and properties. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Jankowski, A (reprint author), Univ Calif Lawrence Livermore Natl Lab, 8000 E Ave, Livermore, CA 94550 USA. NR 13 TC 5 Z9 5 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-501-3 J9 MATER RES SOC SYMP P PY 2000 VL 593 BP 489 EP 492 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BQ70Z UT WOS:000089239300076 ER PT J AU Dumas, P Carr, GL Williams, GP AF Dumas, P Carr, GL Williams, GP TI Enhancing the lateral resolution in infrared microspectrometry by using synchrotron radiation: applications and perspectives SO ANALUSIS LA English DT Article ID PERFORMANCE AB The use of a much brighter source than the conventional blackbody allows an enhancement in lateral resolution in microanalysis using infrared spectroscopy, which thus, becomes limited only by the diffraction criteria. Numerous new applications have been performed in various research fields, which highlight the usefulness of such a new analytical technique. C1 Ctr Univ Paris Sud, LURE, F-91898 Orsay, France. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Dumas, P (reprint author), Ctr Univ Paris Sud, LURE, BP 34, F-91898 Orsay, France. NR 11 TC 34 Z9 34 U1 0 U2 4 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 0365-4877 J9 ANALUSIS JI Analusis PD JAN-FEB PY 2000 VL 28 IS 1 BP 68 EP 74 DI 10.1051/analusis:2000280068 PG 7 WC Chemistry, Analytical SC Chemistry GA 308KR UT WOS:000086710700012 ER PT J AU Castro, A Okinaka, RT AF Castro, A Okinaka, RT TI Ultrasensitive, direct detection of a specific DNA sequence of Bacillus anthracis in solution SO ANALYST LA English DT Article ID POLYMERASE CHAIN-REACTION; PCR; MOLECULES; ERRORS; SPORES AB A very fast and ultrasensitive method has been developed for the detection and quantitation of specific nucleic and sequences of bacterial origin in solution. The method is based on a two-color, single fluorescent molecule detection technique developed in our laboratory. The technique was applied to the detection of Bacillus anthracis DNA in solution. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Castro, A (reprint author), Univ Calif Los Alamos Natl Lab, MS-D454, Los Alamos, NM 87545 USA. EM acx@lanl.gov NR 16 TC 25 Z9 29 U1 0 U2 4 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0003-2654 J9 ANALYST JI Analyst PY 2000 VL 125 IS 1 BP 9 EP 11 DI 10.1039/a908067h PG 3 WC Chemistry, Analytical SC Chemistry GA 271RT UT WOS:000084607800003 PM 10885062 ER PT J AU Dindal, AB Buchanan, MV Jenkins, RA Bayne, CK AF Dindal, AB Buchanan, MV Jenkins, RA Bayne, CK TI Determination of cocaine and heroin vapor pressures using commercial and illicit samples SO ANALYST LA English DT Article ID GAS-CHROMATOGRAPHIC ANALYSIS; BLENDING SYSTEM AB The establishment of drug vapor pressure reference values provides valuable information in the development of vapor sensing devices for drug detection. The purpose of this work was to determine equilibrium headspace vapor pressures for commercial and illicit drug samples for use in such applications. Samples of cocaine, both free base and hydrochloride forms, and heroin hydrochloride were evaluated. The procedure used to measure the vapor pressures was a modification of a previously published method. Vapor pressure values at 20 degrees C previously reported for cocaine free base range from 0.37 x 10(-7) to 1.20 x 10(-7) Torr. The vapor pressure value determined in this study was 2.96 x 10(-7) Torr. It is likely that the discrepancies are due to differences in experimental conditions, varying sources of samples, and uncertainty in the methodologies. When the values were compared for commercial (99% purity) and illicit (unknown purity) sources of cocaine free base, there were no statistical differences in the projected room temperature (20 degrees C) vapor pressure values. However, the commercial and illicit samples of cocaine hydrochloride did show statistical differences. Although no comparison was made with the vapor pressure values for a pure, commercial sample, the vapor pressures of heroin hydrochloride (81% purity) at various temperatures were determined using the method developed for cocaine and are reported in this paper. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Dindal, AB (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008,Bldg 4500 S,MS-6120, Oak Ridge, TN 37831 USA. RI Buchanan, Michelle/J-1562-2016 OI Buchanan, Michelle/0000-0002-8078-4575 NR 11 TC 8 Z9 8 U1 1 U2 5 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0003-2654 J9 ANALYST JI Analyst PY 2000 VL 125 IS 8 BP 1393 EP 1396 DI 10.1039/b004298f PG 4 WC Chemistry, Analytical SC Chemistry GA 340HW UT WOS:000088527900006 PM 11002921 ER PT J AU Cullum, BM Griffin, GD Miller, GH Vo-Dinh, T AF Cullum, BM Griffin, GD Miller, GH Vo-Dinh, T TI Intracellular measurements in mammary carcinoma cells using fiber-optic nanosensors SO ANALYTICAL BIOCHEMISTRY LA English DT Article DE nanosensor; biosensor; fiber-optic; benzo[a]pyrene; benzo[a]pyrene tetrol; carcinogen; cancer; intracellular measurements ID BENZOPYRENE METABOLITE; SENSORS; BIOSENSOR; MOLECULES AB Submicrometer fiber-optic biosensors have been developed and used to measure toxic chemicals within single cells. Optical fibers that have been pulled to a distal-end diameter of less than 1 mu m are coated with antibodies to selectively bind the species of interest. This paper describes the use of these fibers to selectively measure the concentration of benzo[a]pyrene tetrol (BPT), a metabolite of benzo[a]pyrene, within individual cells of two different cell lines, human mammary carcinoma cells and rat liver epithelial cells. The results from these measurements have been used to determine the sensitivity, reproducibility, and usefulness of these nanosensors. The detection limit of these biosensors has been determined to be 0.64 +/- 0.17 x 10(-11) M for BPT. (C) 2000 Academic Press. C1 Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, Oak Ridge, TN 37831 USA. RP Vo-Dinh, T (reprint author), Oak Ridge Natl Lab, Div Life Sci, Adv Monitoring Dev Grp, POB 2008, Oak Ridge, TN 37831 USA. NR 19 TC 68 Z9 71 U1 1 U2 12 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD JAN 1 PY 2000 VL 277 IS 1 BP 25 EP 32 DI 10.1006/abio.1999.4341 PG 8 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 282RG UT WOS:000085231800004 PM 10610686 ER PT J AU Dunn, WC Jacobson, SC Waters, LC Kroutchinina, N Khandurina, J Foote, RS Justice, MJ Stubbs, LJ Ramsey, JM AF Dunn, WC Jacobson, SC Waters, LC Kroutchinina, N Khandurina, J Foote, RS Justice, MJ Stubbs, LJ Ramsey, JM TI PCR amplification and analysis of simple sequence length polymorphisms in mouse DNA using a single microchip device SO ANALYTICAL BIOCHEMISTRY LA English DT Article ID CAPILLARY ELECTROPHORESIS; PERFORMANCE; GENOME; MAP C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Baylor Univ, Coll Med, Dept Mol & Human Genet, Houston, TX 77030 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Human Genome, Livermore, CA 94550 USA. RP Ramsey, JM (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008, Oak Ridge, TN 37831 USA. OI Stubbs, Lisa/0000-0002-9556-1972 NR 14 TC 33 Z9 35 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD JAN 1 PY 2000 VL 277 IS 1 BP 157 EP 160 DI 10.1006/abio.1999.4397 PG 4 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 282RG UT WOS:000085231800019 PM 10610701 ER PT J AU Van Orden, A Keller, RA Ambrose, WP AF Van Orden, A Keller, RA Ambrose, WP TI High-throughput flow cytometric DNA fragment sizing SO ANALYTICAL CHEMISTRY LA English DT Article ID CAPILLARY-ELECTROPHORESIS; NUCLEIC-ACIDS; MASS-SPECTROMETRY; MOLECULES; SEPARATION; POLYMER AB The rate of detection and sizing of individual fluorescently labeled DNA fragments in conventional single-molecule now cytometry (SMFC) is limited by optical saturation, photon-counting statistics, and fragment overlap to similar to 100 fragments/s. We have increased the detection rate for DNA fragment sizing in SMFC to similar to 2000 fragments/s by parallel imaging of the fluorescence from individual DNA molecules, stained with a fluorescent intercalating dye, as they passed through a planar sheet of excitation laser light, resulting in order of magnitude improvements in the measurement speed and the sample throughout compared to conventional SMFC. Fluorescence bursts were measured from a fM solution of DNA fragments ranging in size from 7 to 154 kilobase pairs. A data acquisition time of only a few seconds was sufficient to determine the DNA fragment size distribution. A linear relationship between the number of detected photons per burst and the DNA fragment size was confirmed. Application of this parallel fluorescence imaging method will lead to improvements in the speed, throughput, and sensitivity of other types of flow-based analyses involving the study of single molecules, chromosomes, cells, etc. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, MS M888, Los Alamos, NM 87545 USA. RP Ambrose, WP (reprint author), Colorado State Univ, Dept Chem, Ft Collins, CO 80523 USA. RI Van Orden, Alan/N-4219-2015 NR 33 TC 39 Z9 39 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JAN 1 PY 2000 VL 72 IS 1 BP 37 EP 41 DI 10.1021/ac990782i PG 5 WC Chemistry, Analytical SC Chemistry GA 271GZ UT WOS:000084587000020 PM 10655632 ER PT J AU Martin, SJ Bandey, HL Cernosek, RW Hillman, AR Brown, MJ AF Martin, SJ Bandey, HL Cernosek, RW Hillman, AR Brown, MJ TI Equivalent-circuit model for the thickness-shear mode resonator with a viscoelastic film near film resonance SO ANALYTICAL CHEMISTRY LA English DT Article ID QUARTZ-CRYSTAL MICROBALANCE; MODULUS AB We derive a lumped-element, equivalent-circuit model for the thickness-shear mode (TSM) resonator with a viscoelastic film. This modified Butterworth-Van Dyke model includes in the motional branch a series LCR resonator, representing the quartz resonance, and a parallel LCR resonator, representing the film resonance. This model is valid in the vicinity of film resonance, which occurs when the acoustic phase shift across the film is an odd multiple of pi/2 rad. For low-loss films, this model accurately predicts the frequency changes and. damping that arise at resonance and is a reasonable approximation away from resonance. Elements of the parallel LCR resonator are explicitly related to film properties and can be interpreted in terms of elastic energy storage and viscous power dissipation. The model leads to a simple graphical interpretation of the coupling between the quartz and film resonances and facilitates understanding of the resulting responses. These responses are compared with predictions from the transmission-line and Sauerbrey models. C1 Sandia Natl Labs, Microsensor Res & Dev Dep, Albuquerque, NM 87185 USA. Univ Leicester, Dept Chem, Leicester LE1 7RH, Leics, England. RP Martin, SJ (reprint author), Sandia Natl Labs, Microsensor Res & Dev Dep, POB 5800, Albuquerque, NM 87185 USA. OI Hillman, Robert/0000-0003-1868-5717 NR 20 TC 68 Z9 68 U1 2 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD JAN 1 PY 2000 VL 72 IS 1 BP 141 EP 149 DI 10.1021/ac9908290 PG 9 WC Chemistry, Analytical SC Chemistry GA 271GZ UT WOS:000084587000034 PM 10655646 ER PT J AU Corbett, JD AF Corbett, JD TI Polyanionic clusters and networks of the early p-element metals in the solid state: Beyond the Zintl boundary SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Review DE cluster compounds; indium; thallium; Zintl anions; Zintl phases ID POST-TRANSITION-METALS; STABLE HOMOPOLYATOMIC ANIONS; CRYSTAL-STRUCTURE; INDIUM CLUSTERS; CONFIGURATIONAL QUESTIONS; HETEROATOMIC POLYANIONS; HETEROPOLYATOMIC ANIONS; PARAMAGNETIC PROPERTIES; INTERMETALLIC COMPOUNDS; HOMOATOMIC POLYANIONS C1 Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Corbett, JD (reprint author), Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. NR 156 TC 256 Z9 256 U1 4 U2 38 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 4 BP 670 EP + DI 10.1002/(SICI)1521-3773(20000218)39:4<670::AID-ANIE670>3.0.CO;2-M PG 22 WC Chemistry, Multidisciplinary SC Chemistry GA 286YK UT WOS:000085476300001 ER PT J AU Cai, M Marlow, AL Fettinger, JC Fabris, D Haverlock, TJ Moyer, BA Davis, JT AF Cai, M Marlow, AL Fettinger, JC Fabris, D Haverlock, TJ Moyer, BA Davis, JT TI Binding cesium ions with nucleosides: Templated self-assembly of isoguanosine pentamers SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE cesium; hydrogen bonds; ionophores; nucleosides; supramolecular chemistry ID QUARTETS; DNA; IONOPHORES; ISOGUANINE C1 Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. Univ Maryland Baltimore Cty, Dept Chem & Biochem, Baltimore, MD 21228 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Davis, JT (reprint author), Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. RI Solominow, Sonia/A-4021-2008; Moyer, Bruce/L-2744-2016 OI Moyer, Bruce/0000-0001-7484-6277 NR 18 TC 63 Z9 63 U1 1 U2 6 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 7 BP 1283 EP + DI 10.1002/(SICI)1521-3773(20000403)39:7<1283::AID-ANIE1283>3.0.CO;2-R PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 303JK UT WOS:000086418600029 ER PT J AU Neu, MP Matonic, JH Ruggiero, CE Scott, BL AF Neu, MP Matonic, JH Ruggiero, CE Scott, BL TI Structural characterization of a plutonium(IV) siderophore complex: Single-crystal structure of Pu-desferrioxamine E SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE actinides; hydrogen bonds; siderophores ID FERRIOXAMINE-E C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Neu, MP (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Mail Stop G739, Los Alamos, NM 87545 USA. RI Scott, Brian/D-8995-2017; OI Scott, Brian/0000-0003-0468-5396; Matonic, John/0000-0002-6059-1514 NR 21 TC 48 Z9 48 U1 0 U2 13 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 8 BP 1442 EP + DI 10.1002/(SICI)1521-3773(20000417)39:8<1442::AID-ANIE1442>3.0.CO;2-F PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 306LW UT WOS:000086599000012 ER PT J AU Chavez, DE Hiskey, MA Gilardi, RD AF Chavez, DE Hiskey, MA Gilardi, RD TI 3,3 '-azobis(6-amino-1,2,4,5-tetrazine): A novel high-nitrogen energetic material SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE azo compounds; explosives; nitrogen heterocycles; oxidations ID 3,6-DIAMINO-1,2,4,5-TETRAZINE C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USN, Res Lab, Struct Matter Lab, Washington, DC 20375 USA. RP Hiskey, MA (reprint author), Univ Calif Los Alamos Natl Lab, MS C920, Los Alamos, NM 87545 USA. NR 15 TC 239 Z9 263 U1 5 U2 45 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 10 BP 1791 EP + DI 10.1002/(SICI)1521-3773(20000515)39:10<1791::AID-ANIE1791>3.0.CO;2-9 PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 315PV UT WOS:000087122900013 ER PT J AU Chrisstoffels, LAJ Adronov, A Frechet, JMJ AF Chrisstoffels, LAJ Adronov, A Frechet, JMJ TI Surface-confined light harvesting, energy transfer, and amplification of fluorescence emission in chromophore-labeled self-assembled monolayers SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE chromophores; energy transfer; fluorescence spectroscopy; light harvesting; monolayers ID LANGMUIR-BLODGETT-FILMS; THERMAL-STABILITY; ELECTRON-TRANSFER; CRYSTAL VIOLET; RHODAMINE-B; DENDRIMERS; GOLD; INTRALAYER; INTERLAYER; ANTENNA C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Frechet, JMJ (reprint author), Univ Calif Berkeley, Dept Chem, 718 Latimer Hall, Berkeley, CA 94720 USA. OI Frechet, Jean /0000-0001-6419-0163 NR 56 TC 77 Z9 77 U1 2 U2 16 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 12 BP 2163 EP + DI 10.1002/1521-3773(20000616)39:12<2163::AID-ANIE2163>3.0.CO;2-X PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA 328LA UT WOS:000087851300034 ER PT J AU Khutoretsky, VM Matveeva, NB Gakh, AA AF Khutoretsky, VM Matveeva, NB Gakh, AA TI Hexanitroisobutene dianion salts SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE conjugation; dendrimers; fluorination; hydrogenation; Y-aromaticity ID TRIMETHYLENEMETHANE DIANION; Y-AROMATICITY; QUESTION; RESONANCE C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RAS, ND Zelinskii Organ Chem Inst, Moscow 117913, Russia. RP Gakh, AA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 22 TC 4 Z9 5 U1 1 U2 1 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 14 BP 2545 EP + DI 10.1002/1521-3773(20000717)39:14<2545::AID-ANIE2545>3.0.CO;2-Y PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 337FT UT WOS:000088347300037 ER PT J AU Sozzani, P Comotti, A Simonutti, R Meersmann, T Logan, JW Pines, A AF Sozzani, P Comotti, A Simonutti, R Meersmann, T Logan, JW Pines, A TI A porous crystalline molecular solid explored by hyperpolarized xenon SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article ID LASER-POLARIZED XENON; XE-129 NMR; CHEMICAL-SHIFT; ZEOLITES; SURFACE; SIEVES; ENHANCEMENT; BINDING; PORES; C-13 C1 Univ Milan, Dept Mat Sci, I-20125 Milan, Italy. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Sozzani, P (reprint author), Univ Milan, Dept Mat Sci, Via R Cozzi 53, I-20125 Milan, Italy. NR 38 TC 145 Z9 145 U1 1 U2 16 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 15 BP 2695 EP 2698 DI 10.1002/1521-3773(20000804)39:15<2695::AID-ANIE2695>3.0.CO;2-M PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 343KU UT WOS:000088702200008 ER PT J AU Shin, YS Liu, J Wang, LQ Nie, ZM Samuels, WD Fryxell, GE Exarhos, GJ AF Shin, YS Liu, J Wang, LQ Nie, ZM Samuels, WD Fryxell, GE Exarhos, GJ TI Ordered hierarchical porous materials: Towards tunable size- and shape-selective microcavities in nanoporous channels SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article ID MESOPOROUS MOLECULAR-SIEVES; FUNCTIONALIZED MONOLAYERS; AMINO-GROUPS; TEMPLATE; SILICA; CONDENSATION; KNOEVENAGEL; CATALYSTS; ZEOLITES; SURFACE C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, Richland, WA 99352 USA. EM jun.liu@pnl.gov NR 48 TC 58 Z9 59 U1 3 U2 31 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA POSTFACH 101161, 69451 WEINHEIM, GERMANY SN 1433-7851 EI 1521-3773 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 15 BP 2702 EP 2707 DI 10.1002/1521-3773(20000804)39:15<2702::AID-ANIE2702>3.3.CO;2-6 PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA 343KU UT WOS:000088702200010 ER PT J AU Macchi, P Iversen, BB Sironi, A Chakoumakos, BC Larsen, FK AF Macchi, P Iversen, BB Sironi, A Chakoumakos, BC Larsen, FK TI Interanionic O-H...O interactions: The charge density point of view SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article ID HYDROGEN-BOND; NEUTRON-DIFFRACTION; SALT C1 Univ Aarhus, Dept Chem, DK-8000 Aarhus C, Denmark. Dipartmento Chim Strutturale & Stereochim Inorgan, I-20133 Milan, Italy. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Macchi, P (reprint author), Univ Aarhus, Dept Chem, DK-8000 Aarhus C, Denmark. RI Macchi, Piero/A-7562-2012; Chakoumakos, Bryan/A-5601-2016; Angelo, Sironi/S-5718-2016 OI Macchi, Piero/0000-0001-6292-9825; Chakoumakos, Bryan/0000-0002-7870-6543; Angelo, Sironi/0000-0001-6902-6987 NR 28 TC 55 Z9 55 U1 0 U2 13 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 15 BP 2719 EP 2722 DI 10.1002/1521-3773(20000804)39:15<2719::AID-ANIE2719>3.0.CO;2-8 PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 343KU UT WOS:000088702200015 ER PT J AU Wang, YX Lin, JH Du, Y Qin, RW Han, B Loong, CK AF Wang, YX Lin, JH Du, Y Qin, RW Han, B Loong, CK TI A hexagonal perovskite intergrowth compound: La2Ca2MnO7 SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article ID CRYSTAL-CHEMISTRY; MAGNETORESISTANCE C1 Peking Univ, State Key Lab Rare Earth Mat Chem & Applicat, Beijing 100871, Peoples R China. Peking Univ, Dept Chem Mat, Beijing 100871, Peoples R China. Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Lin, JH (reprint author), Peking Univ, State Key Lab Rare Earth Mat Chem & Applicat, Beijing 100871, Peoples R China. NR 10 TC 17 Z9 19 U1 1 U2 14 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 15 BP 2730 EP 2732 DI 10.1002/1521-3773(20000804)39:15<2730::AID-ANIE2730>3.0.CO;2-L PG 3 WC Chemistry, Multidisciplinary SC Chemistry GA 343KU UT WOS:000088702200019 ER PT J AU Michalczyk, R Schmidt, JG Moody, E Li, ZZ Wu, RL Dunlap, RB Odom, JD Silks, LA AF Michalczyk, R Schmidt, JG Moody, E Li, ZZ Wu, RL Dunlap, RB Odom, JD Silks, LA TI Unusual C-H center dot center dot center dot Se=C interactions in aldols of chiral N-acyl selones detected by gradient-selected H-1-Se-77 HMQC NMR spectroscopy and X-ray crystallography SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article ID MAGNETIC-RESONANCE SPECTROSCOPY; O HYDROGEN-BOND; STRUCTURAL IMPLICATIONS; DERIVATIZING AGENTS; OXAZOLIDINE-2-SELONES; QUANTITATION; ALCOHOLS; OXAZOLE C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. RP Silks, LA (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, MS E529, Los Alamos, NM 87545 USA. OI Michalczyk, Ryszard/0000-0001-8839-6473 NR 28 TC 18 Z9 18 U1 0 U2 4 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 17 BP 3067 EP 3070 DI 10.1002/1521-3773(20000901)39:17<3067::AID-ANIE3067>3.0.CO;2-D PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 352PV UT WOS:000089227800010 ER PT J AU Liu, FC John, KD Scott, BL Baker, RT Ott, KC Tumas, W AF Liu, FC John, KD Scott, BL Baker, RT Ott, KC Tumas, W TI Synthesis and characterization of iron silasesquioxane phosphane complexes SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article ID EPOXIDATION CATALYSTS; ACTIVE-SITES; TITANIUM; ALUMINOSILSESQUIOXANES; ALUMINOSILICATES; ZEOLITES; SURFACES; GEOMETRY; MODELS; BOND C1 Univ Calif Los Alamos Natl Lab, Los Alamos Catalysis Initiat, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Baker, RT (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos Catalysis Initiat, Chem Sci & Technol Div, MS J514, Los Alamos, NM 87545 USA. RI Scott, Brian/D-8995-2017; OI Scott, Brian/0000-0003-0468-5396; John, Kevin/0000-0002-6181-9330 NR 23 TC 25 Z9 25 U1 1 U2 2 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 17 BP 3127 EP 3130 DI 10.1002/1521-3773(20000901)39:17<3127::AID-ANIE3127>3.0.CO;2-F PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 352PV UT WOS:000089227800032 ER PT J AU Zhang, JH Nicholas, JB Haw, JF AF Zhang, JH Nicholas, JB Haw, JF TI NMR and theoretical study of acid sites formed by adsorption of SO3 onto oxide surfaces SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE density functional calculations; heterogeneous catalysis; NMR spectroscopy; sulfur; surface chemistry ID SULFATED ZIRCONIA; SOLID ACIDS; AB-INITIO; CATALYSTS; CHEMISTRY C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ So Calif, Loker Hydrocarbon Res Inst, Los Angeles, CA 90089 USA. Univ So Calif, Dept Chem, Los Angeles, CA 90089 USA. Texas A&M Univ, Dept Chem, Austin, TX USA. RP Nicholas, JB (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. NR 17 TC 14 Z9 14 U1 0 U2 5 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 18 BP 3302 EP + DI 10.1002/1521-3773(20000915)39:18<3302::AID-ANIE3302>3.0.CO;2-T PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 356FP UT WOS:000089433600024 ER PT J AU Boldyrev, AI Li, X Wang, LS AF Boldyrev, AI Li, X Wang, LS TI Experimental observation of pentaatomic tetracoordinate planar Si- and Ge-containing molecules: MAl4- and MAl4 SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE ab initio calculations; bond theory; germanium; photoelectron spectroscopy; silicon ID PHOTOELECTRON-SPECTROSCOPY; CARBON; GEOMETRIES C1 Utah State Univ, Dept Chem & Biochem, Logan, UT 84322 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Washington State Univ, Dept Phys, Richland, WA 99352 USA. RP Boldyrev, AI (reprint author), Utah State Univ, Dept Chem & Biochem, Logan, UT 84322 USA. RI Boldyrev, Alexander/C-5940-2009 OI Boldyrev, Alexander/0000-0002-8277-3669 NR 15 TC 50 Z9 50 U1 1 U2 8 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 18 BP 3307 EP + DI 10.1002/1521-3773(20000915)39:18<3307::AID-ANIE3307>3.0.CO;2-# PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA 356FP UT WOS:000089433600026 ER PT J AU Li, X Zhang, HF Wang, LS Geske, GD Boldyrev, AI AF Li, X Zhang, HF Wang, LS Geske, GD Boldyrev, AI TI Pentaatomic tetracoordinate planar carbon, [CAl4](2-): A new structural unit and its salt complexes SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE ab initio calculations; aluminum; charge transfer; coordination chemistry; photoelectron spectroscopy ID PHOTOELECTRON-SPECTROSCOPY; STABILIZATION C1 Utah State Univ, Dept Chem & Biochem, Logan, UT 84322 USA. Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Wang, LS (reprint author), Utah State Univ, Dept Chem & Biochem, Logan, UT 84322 USA. RI Boldyrev, Alexander/C-5940-2009 OI Boldyrev, Alexander/0000-0002-8277-3669 NR 22 TC 132 Z9 134 U1 2 U2 24 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 20 BP 3630 EP 3633 DI 10.1002/1521-3773(20001016)39:20<3630::AID-ANIE3630>3.3.CO;2-I PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 366MW UT WOS:000090010000016 ER PT J AU Harrison, WTA Phillips, MLF Stanchfield, J Nenoff, TM AF Harrison, WTA Phillips, MLF Stanchfield, J Nenoff, TM TI (CN3H6)(4)[Zn-3(SeO3)(5)]: The first organically templated selenite SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article ID HYDROTHERMAL SYNTHESES; PHOSPHATES; ZEOLITE C1 Univ Aberdeen, Dept Chem, Aberdeen AB24 3UE, Scotland. Sandia Natl Labs, Catalysis & Chem Technol Dept, Albuquerque, NM 87185 USA. RP Harrison, WTA (reprint author), Univ Aberdeen, Dept Chem, Aberdeen AB24 3UE, Scotland. NR 17 TC 104 Z9 105 U1 1 U2 3 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 21 BP 3808 EP + DI 10.1002/1521-3773(20001103)39:21<3808::AID-ANIE3808>3.0.CO;2-E PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 371WL UT WOS:000165202200012 ER PT J AU Huynh, MHV White, PS Meyer, TJ AF Huynh, MHV White, PS Meyer, TJ TI Proton-coupled electron transfer from sulfur: A S-H/S-D kinetic isotope effect of >= 31.1 SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE isotope effects; kinetics; osmium; reductions; S ligands ID OSMIUM HYDRAZIDO; ATOM TRANSFER; COMPLEXES; OXIDATION; <(BPY)2(PY)RU(O)>2+; TRANSITION; MECHANISMS; INSERTION; RUTHENIUM; NITROGEN C1 Univ N Carolina, Dept Chem, Venable & Kenan Labs, Chapel Hill, NC 27599 USA. RP Huynh, MHV (reprint author), Univ Calif Los Alamos Natl Lab, Div Chem, MS J514, Los Alamos, NM 87545 USA. NR 35 TC 29 Z9 29 U1 1 U2 8 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2000 VL 39 IS 22 BP 4101 EP 4104 DI 10.1002/1521-3773(20001117)39:22<4101::AID-ANIE4101>3.0.CO;2-E PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 377DX UT WOS:000165497600027 ER PT J AU Frauenfelder, H McMahon, BH AF Frauenfelder, H McMahon, BH TI Energy landscape and fluctuations in proteins SO ANNALEN DER PHYSIK LA English DT Article DE proteins; energy landscape; conformational motions; relaxations; fluctuations ID CYTOCHROME-C-OXIDASE; PHOTOSYNTHETIC REACTION-CENTER; CHEMICAL-REACTION DYNAMICS; INDUCED STRUCTURAL-CHANGES; LIGAND-BINDING; RHODOBACTER-SPHAEROIDES; HEME-PROTEINS; CONFORMATIONAL RELAXATION; MOLECULAR-DYNAMICS; ELECTRON-TRANSFER AB Complex systems such as biomolecules or glasses do not exist in a unique structure, but can assume a very large number of somewhat different conformations. The organization of the conformations can be described in the energy (or conformation) landscape, where individual valleys are called conformational substates. Proteins are systems where the energy landscape has been studied in some detail. Their landscape is organized in a hierarchy that contains three types of substates, taxonomic, statistical, and few-level. Conformational substates are found in a wide variety of proteins. Some of their characteristics are described and the open experimental and theoretical problems are listed. C1 Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Frauenfelder, H (reprint author), Los Alamos Natl Lab, Ctr Nonlinear Studies, MS B258, Los Alamos, NM 87545 USA. EM frauenfelder@lanl.gov NR 91 TC 38 Z9 38 U1 1 U2 3 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY SN 0003-3804 J9 ANN PHYS-BERLIN JI Ann. Phys.-Berlin PY 2000 VL 9 IS 9-10 BP 655 EP 667 DI 10.1002/1521-3889(200010)9:9/10<655::AID-ANDP655>3.0.CO;2-Z PG 13 WC Physics, Multidisciplinary SC Physics GA 363DL UT WOS:000089819600002 ER PT J AU Zurek, WH AF Zurek, WH TI Einselection and decoherence from an information theory perspective SO ANNALEN DER PHYSIK LA English DT Article; Proceedings Paper CT Symposia on Quantum theory Centenary CY DEC 11-15, 2000 CL BERLIN, GERMANY DE decoherence; einselection; information ID QUANTUM BROWNIAN-MOTION; STATE DETERMINATION; INTEGRAL APPROACH; COHERENT STATES; WAVE PACKET; ENVIRONMENT; PREDICTABILITY; CLASSICALITY; CHANNEL AB We introduce and investigate a simple model of conditional quantum dynamics. It allows for a discussion of the information-theoretic aspects of quantum measurements, decoherence, and environment-induced superselection (einselection). C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Zurek, WH (reprint author), Univ Calif Los Alamos Natl Lab, T-6, Los Alamos, NM 87545 USA. NR 33 TC 141 Z9 142 U1 1 U2 9 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0003-3804 J9 ANN PHYS-BERLIN JI Ann. Phys.-Berlin PY 2000 VL 9 IS 11-12 BP 855 EP 864 DI 10.1002/1521-3889(200011)9:11/12<855::AID-ANDP855>3.3.CO;2-B PG 10 WC Physics, Multidisciplinary SC Physics GA 381FA UT WOS:000165750600005 ER PT J AU Banerjee, B AF Banerjee, B TI Mapping software: Are we nearing standardization? SO ANNALS OF SOFTWARE ENGINEERING LA English DT Review ID FORMAL METHODS; SYSTEMS; SPECIFICATION; STATECHARTS; DESIGN AB As software technologies advance, the software community uses the newest and most powerful technology and associated notations. However, mapping software with a set of notations that would survive the test of time is becoming increasingly difficult. A survey of current methodologies indicates that half-lives of various software notations are short. The dependence of software notations on programming languages and environment specific methodologies often makes these notations obsolete. In this paper, development of a standard set of software notations that is independent of programming paradigms, yet extensible enough to accommodate programming needs, is proposed. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Banerjee, B (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 1022-7091 J9 ANN SOFTW ENG JI Ann. Softw. Eng. PY 2000 VL 10 BP 373 EP 387 DI 10.1023/A:1018908320986 PG 15 WC Computer Science, Software Engineering SC Computer Science GA 372YB UT WOS:000165260700015 ER PT J AU Nogales, E AF Nogales, E TI Structural insights into microtubule function SO ANNUAL REVIEW OF BIOCHEMISTRY LA English DT Review DE tubulin; dynamic instability; antimitotic drugs; microtubule-associated proteins ID BACTERIAL-CELL-DIVISION; BETA-TUBULIN ISOTYPES; COUPLED RECEPTOR KINASE-2; GTP-BINDING-PROTEIN; GAMMA-TUBULIN; ALPHA-TUBULIN; CRYSTAL-STRUCTURE; POSTTRANSLATIONAL MODIFICATIONS; DYNAMIC INSTABILITY; COLCHICINE-BINDING AB Microtubules are polymers that are essential for, among other functions, cell transport and cell division in all eukaryotes. The regulation of the microtubule system includes transcription of different tubulin isotypes, folding of alpha/beta-tubulin heterodimers, post-translation modification of tubulin, and nucleotide-based microtubule dynamics, as well as interaction with numerous microtubule-associated proteins that are themselves regulated. The result. is the precise temporal and spatial pattern of microtubules that is observed throughout the cell cycle. The recent high-resolution analysis of the structure of tubulin and the microtubule has brought new insight to the study of microtubule function and regulation, as well as the mode of action of antimitotic drugs that disrupt normal microtubule behavior. The combination of structural, genetic, biochemical, and biophysical data should soon give us a fuller understanding of the exquisite details in the regulation of the microtubule cytoskeleton. C1 Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Nogales, E (reprint author), Univ Calif Berkeley, Dept Mol & Cell Biol, 229 Stanley Hall, Berkeley, CA 94720 USA. NR 146 TC 333 Z9 341 U1 8 U2 58 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0066-4154 J9 ANNU REV BIOCHEM JI Annu. Rev. Biochem. PY 2000 VL 69 BP 277 EP 302 DI 10.1146/annurev.biochem.69.1.277 PG 26 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 361QZ UT WOS:000089735700010 PM 10966460 ER PT J AU Berry, EA Guergova-Kuras, M Huang, LS Crofts, AR AF Berry, EA Guergova-Kuras, M Huang, LS Crofts, AR TI Structure and function of cytochrome bc complexes SO ANNUAL REVIEW OF BIOCHEMISTRY LA English DT Review DE oxidoreductase; respiratory chain; electron transfer; crystallography; membrane protein ID IRON-SULFUR PROTEIN; BOVINE HEART-MITOCHONDRIA; SITE-DIRECTED MUTAGENESIS; STEADY-STATE KINETICS; AMINO-ACID-SEQUENCE; C REDUCTASE COMPLEX; UBIHYDROQUINONE OXIDATION SITE; CHLOROPLAST RIESKE PROTEIN; ELECTRON-TRANSFER REACTION; UBIQUINONE-BINDING DOMAIN AB The cytochrome be complexes represent a phylogenetically diverse group of complexes of electron-transferring membrane proteins, most familiarly represented by the mitochondrial and bacterial bc(1) complexes and the chloroplast and cyanobacterial b(6)f complex. All these complexes couple electron transfer to proton translocation across a closed lipid bilayer membrane, conserving the free energy released by the oxidation-reduction process in the form of an electrochemical proton gradient across the membrane. Recent exciting developments include the application of site-directed mutagenesis to define the role of conserved residues, and the emergence over the past five years of X-ray structures for several mitochondrial complexes, and for two important domains of the b(6)f complex. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Inst Biol Physicochim, CNRS, F-75005 Paris, France. Univ Illinois, Dept Biochem, Urbana, IL 61801 USA. Univ Illinois, Ctr Biophys & Computat Biol, Urbana, IL 61801 USA. RP Berry, EA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. FU NIDDK NIH HHS [DK44842] NR 286 TC 336 Z9 346 U1 4 U2 51 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0066-4154 J9 ANNU REV BIOCHEM JI Annu. Rev. Biochem. PY 2000 VL 69 BP 1005 EP 1075 DI 10.1146/annurev.biochem.69.1.1005 PG 71 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 361QZ UT WOS:000089735700031 PM 10966481 ER PT J AU Polla, DL Erdman, AG Robbins, WP Markus, DT Diaz-Diaz, J Rizq, R Nam, Y Brickner, HT Wang, A Krulevitch, P AF Polla, DL Erdman, AG Robbins, WP Markus, DT Diaz-Diaz, J Rizq, R Nam, Y Brickner, HT Wang, A Krulevitch, P TI Microdevices in medicine SO ANNUAL REVIEW OF BIOMEDICAL ENGINEERING LA English DT Review DE microelectromechanical systems; MEMS; bioMEMS; microfabrication; microsystems; biosensors; mass spectrometer; stepper motor; piezoelectricity; surgical microsystems; diagnostic microsystems; therapeutic microsystems ID MEANDER-LINE GEOMETRY; MICROELECTROMECHANICAL SYSTEMS; DRUG-DELIVERY; SILICON; MICROACTUATORS; SENSORS; CHIPS; STEP AB The application of microelectromechanical systems (MEMS) to medicine is described. Three types of biomedical devices are considered, including diagnostic microsystems, surgical microsystems, and therapeutic microsystems. The opportunities of MEMS miniaturization in these emerging disciplines are considered, with emphasis placed on the importance of the technology in providing a better outcome for the patient and a lower overall health care cost. Several case examples in each of these areas are described. Key aspects of MEMS technology as it is applied to these three areas are described, along with some of the fabrication challenges. C1 Univ Minnesota, Dept Biomed Engn, Minneapolis, MN 55455 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Microtechnol, Livermore, CA 94550 USA. RP Polla, DL (reprint author), Univ Minnesota, Dept Biomed Engn, Minneapolis, MN 55455 USA. NR 68 TC 115 Z9 115 U1 2 U2 24 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1523-9829 J9 ANNU REV BIOMED ENG JI Annu. Rev. Biomed. Eng. PY 2000 VL 2 BP 551 EP 576 DI 10.1146/annurev.bioeng.2.1.551 PG 26 WC Engineering, Biomedical SC Engineering GA 364HR UT WOS:000089887400020 PM 11701523 ER PT J AU Wemmer, DE AF Wemmer, DE TI Designed sequence-specific minor groove ligands SO ANNUAL REVIEW OF BIOPHYSICS AND BIOMOLECULAR STRUCTURE LA English DT Review DE molecular recognition; drug design; DNA recognition ID PYRROLE-IMIDAZOLE POLYAMIDES; COVALENT PEPTIDE DIMERS; DNA-BINDING LIGANDS; BASE-PAIR SEQUENCES; DOUBLE-HELICAL DNA; G-C-G; HAIRPIN POLYAMIDE; B-DNA; DISTAMYCIN-A; MOLECULAR RECOGNITION AB In the past decade, a general design for sequence-specific minor groove ligands has evolved, based on the natural products distamycin and netropsin. By utilizing a basic set of design rules for connecting pyrrole, imidazole, and hydroxypyrrole modules, new ligands can be prepared to target almost any sequence of interest with both high affinity and specificity. In this review we present the design rules with a brief history of how they evolved. The structural basis for sequence-specific recognition is explained, together with developments that allow linking of recognition modules that enable targeting of long DNA sequences. Examples of the affinity and specificity that can be achieved with a number of variations on the basic design are given. Recently these molecules have been used to compete with proteins both in vitro and in vivo, and a brief description of the experimental results are given. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Wemmer, DE (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 87 TC 117 Z9 118 U1 1 U2 9 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1056-8700 J9 ANNU REV BIOPH BIOM JI Annu. Rev. Biophys. Biomolec. Struct. PY 2000 VL 29 BP 439 EP 461 DI 10.1146/annurev.biophys.29.1.439 PG 23 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 339RU UT WOS:000088492300015 PM 10940255 ER PT J AU Bleecker, AB Kende, H AF Bleecker, AB Kende, H TI Ethylene: A gaseous signal molecule in plants SO ANNUAL REVIEW OF CELL AND DEVELOPMENTAL BIOLOGY LA English DT Review DE 1-aminocyclopropane-1-carboxylic acid (ACC); Arabidopsis thaliana; ethylene receptors; Raf kinase; two-component system ID RECEPTOR GENE FAMILY; MAP KINASE CASCADE; 1-AMINOCYCLOPROPANE-1-CARBOXYLATE SYNTHASE; ARABIDOPSIS-THALIANA; HORMONE ETHYLENE; RESPONSE PATHWAY; FORMING ENZYME; MUTANT FORMS; KEY ENZYME; NEVER-RIPE AB Ethylene regulates a multitude of plant processes, ranging from seed germination to organ senescence. Of particular economic importance is the role of ethylene as an inducer of fruit ripening. Ethylene is synthesized from S-adenosyl-L-methionine via 1-aminocyclopropane-1-carboxylic acid (ACC). The enzymes catalyzing the two reactions in this pathway are ACC synthase and ACC oxidase. Environmental and endogenous signals regulate ethylene biosynthesis primarily through differential expression of ACC synthase genes. Components of the ethylene signal transduction pathway have been identified by characterization of ethylene-response mutants in Arabidopsis thaliana. One class of mutations, exemplified by etr1, led to the identification of the ethylene receptors, which turned out to be related to bacterial two-component signaling systems. Mutations that eliminate ethylene binding to the receptor yield a dominant, ethylene-insensitive phenotype. CTR1 encodes a Raf-like Ser/Thr protein kinase that acts downstream from the ethylene receptor and may be part of a MAP kinase cascade. Mutants in CTR1 exhibit a constitutive ethylene-response phenotype. Both the ethylene receptors and CTR1 are negative regulators of ethylene responses. EIN2 and EIN3 are epistatic to CTR1, and mutations in either gene lead to ethylene insensitivity. Whereas the function of EIN2 in ethylene transduction is not known, EIN3 is a putative transcription factor involved in regulating expression of ethylene-responsive genes. Biotechnological modifications of ethylene synthesis and of sensitivity to ethylene are promising methods to prevent spoilage of agricultural products such as fruits, whose ripening is induced by ethylene. C1 Univ Wisconsin, Dept Bot, Madison, WI 53706 USA. Univ Wisconsin, Dept Genet, Madison, WI 53706 USA. Michigan State Univ, US DOE, Plant Res Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Bot & Plant Pathol, E Lansing, MI 48824 USA. RP Bleecker, AB (reprint author), Univ Wisconsin, Dept Bot, Madison, WI 53706 USA. RI allasia, valerie/B-4214-2009 NR 68 TC 697 Z9 769 U1 22 U2 231 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1081-0706 J9 ANNU REV CELL DEV BI JI Annu. Rev. Cell Dev. Biol. PY 2000 VL 16 BP 1 EP + DI 10.1146/annurev.cellbio.16.1.1 PG 19 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA 385NH UT WOS:000166010200002 PM 11031228 ER PT J AU Downing, KH AF Downing, KH TI Structural basis for the interaction of tubulin with proteins and drugs that affect microtubule dynamics SO ANNUAL REVIEW OF CELL AND DEVELOPMENTAL BIOLOGY LA English DT Review DE microtubules; microtubule-associated proteins; dynamic instability; antimitotic drugs ID TAXOL-BINDING-SITE; BETA-TUBULIN; CRYOELECTRON MICROSCOPY; CRYSTAL-STRUCTURE; ALPHA-TUBULIN; CELL-DIVISION; KINESIN MOTOR; ESCHERICHIA-COLI; AMINO-ACIDS; FTSZ AB The microtubule cytoskeleton is a highly regulated system. At different times in the cell cycle and positions within the organism microtubules can be very stable or highly dynamic. Stability and dynamics are regulated by interaction with a large number of proteins that themselves may change at specific points in the cell cycle. Exogenous ligands can disrupt the normal processes by either increasing or decreasing microtubule stability and inhibiting their dynamic behavior. The recent determination of the structure of tubulin, the main component of microtubules, makes it possible now to begin to understand the details of these interactions. We review here the structure of the tubulin dimer, with particular regard to how proteins and drugs may bind and modulate microtubule dynamics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Donner Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Downing, KH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Donner Lab, Div Life Sci, Berkeley, CA 94720 USA. NR 73 TC 228 Z9 236 U1 1 U2 26 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1081-0706 J9 ANNU REV CELL DEV BI JI Annu. Rev. Cell Dev. Biol. PY 2000 VL 16 BP 89 EP 111 DI 10.1146/annurev.cellbio.16.1.89 PG 25 WC Cell Biology; Developmental Biology SC Cell Biology; Developmental Biology GA 385NH UT WOS:000166010200005 PM 11031231 ER PT J AU Kheshgi, HS Prince, RC Marland, G AF Kheshgi, HS Prince, RC Marland, G TI The potential of biomass fuels in the context of global climate change: Focus on transportation fuels SO ANNUAL REVIEW OF ENERGY AND THE ENVIRONMENT LA English DT Review DE bioenergy; biofuels; ethanol; carbon dioxide ID ETHANOL-PRODUCTION; HYDROGEN-PRODUCTION; CARBON-DIOXIDE; UNITED-STATES; SIMULTANEOUS SACCHARIFICATION; CELLULOSIC BIOMASS; POWER-GENERATION; FAST-PYROLYSIS; SOLID-WASTE; FLUE-GAS AB An ultimate limit on the extent that biomass fuels can be used to displace fossil transportation fuels, and their associated emissions of CO2 will be the land area available to produce the fuels and the efficiencies by which solar radiation can be converted to useable fuels. Currently, the Brazil cane-ethanol system captures 33% of the primary energy content in harvested cane in the form of ethanol. The US corn-ethanol system captures 54% of the primary energy of harvested corn kernels in the form of ethanol. If ethanol is used to substitute for gasoline, avoided fossil fuel CO2 emissions would equal those of the substituted amount minus fossil emissions incurred in producing the cane- or corn-ethanol. In this case, avoided emissions are estimated to be 29% of harvested cane and 14% of harvested corn primary energy. Unless these efficiencies are substantially improved, the displacement of CO2 emissions from transportation fuels in the United States is unlikely to reach 10% using domestic biofuels. Candidate technologies for improving these efficiencies include fermentation of cellulosic biomass and conversion of biomass into electricity, hydrogen, or alcohols for use in electric drive-train vehicles. C1 ExxonMobil Res & Engn Co, Annandale, NJ 08801 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Kheshgi, HS (reprint author), ExxonMobil Res & Engn Co, Annandale, NJ 08801 USA. NR 136 TC 103 Z9 106 U1 8 U2 63 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1056-3466 J9 ANNU REV ENERG ENV JI Annu. Rev. Energ. Environ. PY 2000 VL 25 BP 199 EP 244 DI 10.1146/annurev.energy.25.1.199 PG 46 WC Energy & Fuels; Engineering, Environmental SC Energy & Fuels; Engineering GA 396EZ UT WOS:000166624500008 ER PT J AU Shah, J Nagpal, T Johnson, T Amann, M Carmichael, G Foell, W Green, C Hettelingh, LP Hordijk, L Li, J Peng, C Pu, YF Ramankutty, R Streets, D AF Shah, J Nagpal, T Johnson, T Amann, M Carmichael, G Foell, W Green, C Hettelingh, LP Hordijk, L Li, J Peng, C Pu, YF Ramankutty, R Streets, D TI Integrated analysis for acid rain in Asia: Policy implications and results of RAINS-ASIA model SO ANNUAL REVIEW OF ENERGY AND THE ENVIRONMENT LA English DT Review DE China; regional pollution; transboundary; energy strategies; critical loads; sulfur dioxide ID LONG-RANGE TRANSPORT; SULFUR-DIOXIDE EMISSIONS; AIR-POLLUTION; EAST-ASIA; TRAJECTORY MODEL; DEPOSITION; CHINA; ACIDIFICATION; PRECIPITATION; AEROSOLS AB Fossil fuels account for about 80% of energy consumption in Asia. Because of its abundance and easy recoverability, especially in India and China, coal will remain the fuel of choice in the foreseeable future. If current trends continue, sulfur dioxide emissions from Asia may soon equal the emissions from North America and Europe combined. These trends portend a variety of local, regional, and global environmental impacts. Acid rain damages human health, ecosystems, and built surfaces. Many ecosystems will be unable to absorb these increased acidic depositions, leading to irreversible ecosystem damage with far-reaching implications for health, forestry, agriculture, fisheries, and tourism. RAINS-ASIA is a scenario-generating tool used to estimate the extent of damages caused by acid rain and to review the costs and impacts of alternatives to provide a look into the future. Its use extends from national-, regional-, and city-scale evaluation and inputs for cost-effective options analyses, to international negotiations on transboundary pollution. C1 World Bank, Washington, DC 20433 USA. Int Inst Appl Syst Anal, A-2361 Laxenburg, Austria. Univ Iowa, Dept Chem & Biochem Engn, Iowa City, IA 52240 USA. Resource Management Associates Madison, Madison, WI 53703 USA. Natl Renewable Energy Lab, Washington, DC 20024 USA. Natl Inst Publ Hlth & Environm, NL-3720 BA Bilthoven, Netherlands. Univ Wageningen & Res Ctr, Environm Syst Anal Grp, Wageningen, Netherlands. Ctr Clean Air Policy, Washington, DC 20002 USA. Chinese Acad Sci, Inst Atmospher Phys, Beijing, Peoples R China. Global Environm Facil, Washington, DC 20433 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Shah, J (reprint author), World Bank, 1818 H St NW, Washington, DC 20433 USA. OI Streets, David/0000-0002-0223-1350 NR 104 TC 37 Z9 38 U1 6 U2 33 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1056-3466 J9 ANNU REV ENERG ENV JI Annu. Rev. Energ. Environ. PY 2000 VL 25 BP 339 EP 375 DI 10.1146/annurev.energy.25.1.339 PG 41 WC Energy & Fuels; Engineering, Environmental SC Energy & Fuels; Engineering GA 396EZ UT WOS:000166624500012 ER PT J AU Greene, DL DeCicco, J AF Greene, DL DeCicco, J TI Engineering-economic analyses of automotive fuel economy potential in the United States SO ANNUAL REVIEW OF ENERGY AND THE ENVIRONMENT LA English DT Review DE energy-efficiency; energy conservation; transportation; miles per gallon; GHG emissions ID IMPROVEMENT AB Over the past 25 years more than 20 major studies have examined the technological potential to improve the fuel economy of passenger cars and light trucks in the United States. The majority have used technology/cost analysis, a combination of analytical methods from the disciplines of economics and automotive engineering. In this review we describe the key elements of this methodology, discuss critical issues responsible for the often widely divergent estimates produced by different studies, review the history of this methodology's use, and present results from six recent assessments. Whereas early studies tended to confine their scope to the potential of proven technology over a 10-year time period, more recent studies have focused on advanced technologies, raising questions about how best to include the likelihood of technological change. The review concludes with recommendations for further research. C1 Oak Ridge Natl Lab, Ctr Transportat Anal, Oak Ridge, TN 37831 USA. Amer Council Energy Efficient Econ, Washington, DC 20036 USA. RP Greene, DL (reprint author), Oak Ridge Natl Lab, Ctr Transportat Anal, Oak Ridge, TN 37831 USA. NR 74 TC 22 Z9 22 U1 2 U2 7 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1056-3466 J9 ANNU REV ENERG ENV JI Annu. Rev. Energ. Environ. PY 2000 VL 25 BP 477 EP 535 DI 10.1146/annurev.energy.25.1.477 PG 61 WC Energy & Fuels; Engineering, Environmental SC Energy & Fuels; Engineering GA 396EZ UT WOS:000166624500015 ER PT J AU Fisk, WJ AF Fisk, WJ TI Health and productivity gains from better indoor environments and their relationship with building energy efficiency SO ANNUAL REVIEW OF ENERGY AND THE ENVIRONMENT LA English DT Review DE economics; health; productivity ID RESPIRATORY-TRACT INFECTIONS; OFFICE WORKERS; UNITED-STATES; TASK-PERFORMANCE; ALLERGIC DISEASE; ECONOMIC COSTS; ASTHMA; CHILDREN; SYMPTOMS; SATISFACTION AB Theoretical considerations and empirical data suggest that existing technologies and procedures can improve indoor environments in a manner that significantly increases productivity and health. The existing literature contains moderate to strong evidence that characteristics of buildings and indoor environments significantly influence rates of communicable respiratory illness, allergy and asthma symptoms, sick building symptoms, and worker performance. Whereas there is considerable uncertainty in the estimates of the magnitudes of productivity gains that may be obtained by providing better indoor environments, the projected gains are very large. For the United States, the estimated potential annual savings and productivity gains are $6 to $14 billion from reduced respiratory disease, $1 to $4 billion from reduced allergies and asthma, $10 to $30 billion from reduced sick building syndrome symptoms, and $20 to $160 billion from direct improvements in worker performance that are unrelated to health. Productivity gains that are quantified and demonstrated could serve as a strong stimulus for energy efficiency measures that simultaneously improve the indoor environment. C1 Lawrence Berkeley Natl Lab, Indoor Environm Dept, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Fisk, WJ (reprint author), Lawrence Berkeley Natl Lab, Indoor Environm Dept, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 84 TC 143 Z9 148 U1 5 U2 56 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1056-3466 J9 ANNU REV ENERG ENV JI Annu. Rev. Energ. Environ. PY 2000 VL 25 BP 537 EP 566 DI 10.1146/annurev.energy.25.1.537 PG 30 WC Energy & Fuels; Engineering, Environmental SC Energy & Fuels; Engineering GA 396EZ UT WOS:000166624500016 ER PT J AU Decker, EH Elliott, S Smith, FA Blake, DR Rowland, FS AF Decker, EH Elliott, S Smith, FA Blake, DR Rowland, FS TI Energy and material flow through the urban ecosystem SO ANNUAL REVIEW OF ENERGY AND THE ENVIRONMENT LA English DT Review DE megacity biogeochemistry; city succession; industrial metabolism; air pollution; system simulations ID ATMOSPHERIC CO2 CONCENTRATIONS; PACIFIC EXPLORATORY MISSION; LIQUEFIED PETROLEUM GAS; MEXICO-CITY; AIR-QUALITY; UNITED-STATES; SOLID-WASTE; PARTICULATE MATTER; PEM-WEST; NONMETHANE HYDROCARBONS AB This paper reviews the available data and models on energy and material flows through the world's 25 largest cities. Throughput is categorized as stored, transformed, or passive for the major flow modes. The aggregate, fuel, food, water, and air cycles are all examined. Emphasis is placed on atmospheric pathways because the data are abundant. Relevant models of urban energy and material flows, demography, and atmospheric chemistry are discussed. Earth system-level loops from cities to neighboring ecosystems are identified. Megacities are somewhat independent of their immediate environment for food, fuel, and aggregate inputs, but all are constrained by their regional environment for supplying water and absorbing wastes. We elaborate on analogies with biological metabolism and ecosystem succession as useful conceptual frameworks for addressing urban ecological problems. We conclude that whereas data are numerous for some individual cities, cross-cutting compilations are lacking in biogeochemical analysis and modeling. Synthesis of the existing information will be a crucial first step. Cross-cutting field research and integrated, multidisciplinary simulations will be necessary. C1 Univ New Mexico, Dept Biol, Albuquerque, NM 87131 USA. Los Alamos Natl Lab, Atmospher & Climate Sci Grp, Los Alamos, NM 87545 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. RP Univ New Mexico, Dept Biol, Albuquerque, NM 87131 USA. EM ehdecker@unm.edu; selliott@kokopelli.lanl.gov; fasmith@unm.edu; drblake@uci.edu; rowland@uci.edu NR 284 TC 154 Z9 169 U1 9 U2 89 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 1056-3466 J9 ANNU REV ENERG ENV JI Annu. Rev. Energ. Environ. PY 2000 VL 25 BP 685 EP 740 DI 10.1146/annurev.energy.25.1.685 PG 58 WC Energy & Fuels; Engineering, Environmental SC Energy & Fuels; Engineering GA 396EZ UT WOS:000166624500020 ER PT J AU Cohen, ML AF Cohen, ML TI The theory of real materials SO ANNUAL REVIEW OF MATERIALS SCIENCE LA English DT Review DE calculations; solids; electronic; structural; models ID DIFFERENCE-PSEUDOPOTENTIAL METHOD; BORON-NITRIDE NANOTUBES; ELECTRONIC-PROPERTIES; QUANTUM CONFINEMENT; CARBON; SI; TUBULES; SOLIDS; SEMICONDUCTORS; MICROTUBULES AB It has become possible to explain and predict properties of real materials using ab initio theory. The background, methods, and applications are described. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawerence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Cohen, ML (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM cohen@jungle.berkeley.edu NR 64 TC 42 Z9 45 U1 1 U2 25 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0084-6600 J9 ANNU REV MATER SCI JI Annu. Rev. Mater. Sci. PY 2000 VL 30 BP 1 EP 26 DI 10.1146/annurev.matsci.30.1.1 PG 28 WC Materials Science, Multidisciplinary SC Materials Science GA 354LR UT WOS:000089332400003 ER PT J AU Sniegowski, JJ de Boer, MP AF Sniegowski, JJ de Boer, MP TI IC-compatible polysilicon surface micromachining SO ANNUAL REVIEW OF MATERIALS SCIENCE LA English DT Review DE MEMS; microfabrication; microsensors; microactuators; thin film stress; adhesion ID SELF-ASSEMBLED MONOLAYERS; THIN-FILMS; POLYCRYSTALLINE SILICON; MECHANICAL CHARACTERIZATION; MICROELECTROMECHANICAL SYSTEMS; FRACTURE STRENGTH; STRESS-RELAXATION; STRAIN ANALYSIS; MEMS; ADHESION AB Polysilicon surface micromachining is advancing significantly and many new applications are moving beyond the prototyping phase. Recent technical successes are leading to excitement concerning various uses of devices in optical, wireless, sensor, and many other areas. Incorporation of state-of-the-art integrated circuit (IC) fabrication methods, such as planarization by chemical mechanical polishing (CMP), has enabled extension to a five-level technology. This has opened significant design space, especially for microactuator applications. Recent advancement of in situ microdiagnostics for materials and surface properties has enhanced our understanding of device reliability and performance and will allow devices to operate near well-known materials limits. New IC-compatible materials will further enhance the capabilities of microsystems in terms of performance, reliability, and operation in harsh environments. C1 Sandia Natl Labs, Intelligent Micromachine Dept, Albuquerque, NM 87185 USA. RP Sniegowski, JJ (reprint author), Sandia Natl Labs, Intelligent Micromachine Dept, POB 5800, Albuquerque, NM 87185 USA. EM Sniegojj@sandia.gov; mpdebo@sandia.gov RI de Boer, Maarten/C-1525-2013 OI de Boer, Maarten/0000-0003-1574-9324 NR 104 TC 152 Z9 155 U1 3 U2 23 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0084-6600 J9 ANNU REV MATER SCI JI Annu. Rev. Mater. Sci. PY 2000 VL 30 BP 299 EP 333 DI 10.1146/annurev.matsci.30.1.299 PG 35 WC Materials Science, Multidisciplinary SC Materials Science GA 354LR UT WOS:000089332400012 ER PT J AU Gschneidner, KA Pecharsky, VK AF Gschneidner, KA Pecharsky, VK TI Magnetocaloric materials SO ANNUAL REVIEW OF MATERIALS SCIENCE LA English DT Review DE magnetocaloric effect; mixed lanthanide materials; 3d-materials amorphous alloys; manganites ID MAGNETIC ENTROPY CHANGE; RARE-EARTH-METALS; ROOM-TEMPERATURE; PHASE-TRANSITIONS; HEAT-CAPACITY; WORKING SUBSTANCES; MANGANESE OXIDES; ALLOYS; REFRIGERATION; GADOLINIUM AB In the last decade of the twentieth century there has been a significant increase in research on a more than 100-year old phenomenon-the magnetocaloric effect (MCE). As a result, many new materials with large MCEs (and many with lesser values) have been discovered, and a much better understanding of this magneto-thermal property has resulted. In this review we briefly discuss the principles of magnetic cooling (and heating); the measurement of the magnetocaloric properties by direct and indirect techniques; the special problems that can arise; and the MCE properties of the 4f lanthanide metals, their intra-lanthanide alloys and their compounds [including the giant MCE Gd-5(SixGe1-x)(4) phases]; the 3d transition metals, their alloys and compounds; and mixed lanthanide-3d transition metal materials (including the La manganites). C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Gschneidner, KA (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 143 TC 595 Z9 598 U1 27 U2 200 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0084-6600 J9 ANNU REV MATER SCI JI Annu. Rev. Mater. Sci. PY 2000 VL 30 BP 387 EP 429 DI 10.1146/annurev.matsci.30.1.387 PG 43 WC Materials Science, Multidisciplinary SC Materials Science GA 354LR UT WOS:000089332400015 ER PT J AU Clark, RM Macchiavelli, AO AF Clark, RM Macchiavelli, AO TI The shears mechanism in nuclei SO ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE LA English DT Review DE nuclear structure; gamma-ray spectroscopy; shears mechanism; effective forces ID CONVERSION ELECTRON-SPECTROSCOPY; DIPOLE ROTATIONAL BANDS; OBLATE BANDS; COLLECTIVE OBLATE; MAGNETIC ROTATION; 1ST OBSERVATION; BISMUTH NUCLEI; REGION; PB-197; LIFETIMES AB This chapter reviews the experimental properties of shears bands. The most puzzling characteristic of these structures is the emergence of rotational-like behavior while the nucleus retains a small quadrupole deformation. Regardless of the details of particular theoretical models, it can be shown that the most important degree of freedom in describing the shears mechanism is the shears angle. It is then possible to develop a semiclassical description of the shears mechanism, in which the nature (multipole order) of the interaction between valence protons and neutrons constituting the shears "blades" may be derived and the dynamics of the system described. We discuss the competition between the shears mechanism and collective rotation and mention the connection to "magnetic rotation." Directions for future theoretical and experimental efforts are suggested. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Clark, RM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 88 TC 108 Z9 111 U1 0 U2 1 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0163-8998 J9 ANNU REV NUCL PART S JI Annu. Rev. Nucl. Part. Sci. PY 2000 VL 50 BP 1 EP 36 DI 10.1146/annurev.nucl.50.1.1 PG 36 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387LL UT WOS:000166124000002 ER PT J AU LeCompte, T Diehl, HT AF LeCompte, T Diehl, HT TI The CDF and DO upgrades for Run II SO ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE LA English DT Review DE particle physics; collider; detectors; tracking; calorimeter; muon ID PRODUCTION CROSS-SECTION; TOP-QUARK MASS; P(P)OVER-BAR COLLISIONS; SCINTILLATING STRIPS; HIGGS BOSONS; B-MESON; DETECTOR; SEARCH; DECAYS; COLLABORATION AB The DO and CDF collaborations are preparing their detectors for the Tevatron Run II. A 20-fold increase in integrated luminosity is planned for the first two years of the upcoming run, and the detector subsystems are undergoing substantial improvements to handle the higher rates as well as to better measure the products of the p (p) over bar interactions. This review discusses the physics goals that motivate these detector enhancements and describes in detail the improvements being made to the charged particle tracking, calorimetry, muon identification, and trigger subsystems of both detectors. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP LeCompte, T (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 43 TC 51 Z9 47 U1 0 U2 1 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0163-8998 J9 ANNU REV NUCL PART S JI Annu. Rev. Nucl. Part. Sci. PY 2000 VL 50 BP 71 EP 117 DI 10.1146/annurev.nucl.50.1.71 PG 47 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387LL UT WOS:000166124000004 ER PT J AU Savard, G Werth, G AF Savard, G Werth, G TI Precision nuclear measurements with ion traps SO ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE LA English DT Review DE radioactive isotopes; masses; nuclear moments; hyperfine anomaly ID HYPERFINE-STRUCTURE MEASUREMENTS; SHORT-LIVED ISOTOPES; PENNING-TRAP; GROUND-STATE; MASS-SPECTROMETER; ATOMIC MASS; FREQUENCY STANDARD; SPECTROSCOPY; BA+; G(J)-FACTOR AB Properties of charged particles confinedin ion traps can be determined to high accuracy. The ability to capture stable and unstable isotopes in such traps with high efficiency has led to a series of measurements of gross properties of nuclei. These recent high-accuracy measurements, along with the enabling technological developments and propects for the field, are presented. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Mainz, Inst Phys, D-55099 Mainz, Germany. RP Savard, G (reprint author), Argonne Natl Lab, Div Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 81 TC 16 Z9 16 U1 1 U2 2 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0163-8998 J9 ANNU REV NUCL PART S JI Annu. Rev. Nucl. Part. Sci. PY 2000 VL 50 BP 119 EP 152 DI 10.1146/annurev.nucl.50.1.119 PG 34 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387LL UT WOS:000166124000005 ER PT J AU Glenzinski, DA Heintz, U AF Glenzinski, DA Heintz, U TI Precision measurements of the W boson mass SO ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE LA English DT Review DE W boson; mass; precision; electroweak; Higgs boson ID FERMILAB TEVATRON COLLIDER; PARTON DISTRIBUTIONS; STANDARD MODEL; GLUON DISTRIBUTION; QCD; JET; PROTON; W+/ AB The standard model of electroweak interactions has had great success in describing the observed data over the past three decades. The precision of experimental measurements affords tests of the standard model at the quantum loop level beyond leading order. Despite this success, it is important to continue confronting experimental measurements with the standard model's predictions because any deviation would signal new physics. As a fundamental parameter of the standard model, the mass of the W boson, M-W, is of particular importance. Aside from being an important test of the model itself, a precision measurement of M-W can be used to constrain the mass of the Higgs boson, M-H In this article, we review the principal experimental techniques for determining M-W and discuss their combination into a single precision M-W measurement. We conclude by briefly discussing future prospects for precision measurements of the W boson mass. C1 Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. RP Glenzinski, DA (reprint author), Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. NR 114 TC 3 Z9 3 U1 0 U2 0 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0163-8998 J9 ANNU REV NUCL PART S JI Annu. Rev. Nucl. Part. Sci. PY 2000 VL 50 BP 207 EP 248 DI 10.1146/annurev.nucl.50.1.207 PG 42 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387LL UT WOS:000166124000007 ER PT J AU Barker, AR Kettell, SH AF Barker, AR Kettell, SH TI Developments in rare kaon decay physics SO ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE LA English DT Review DE CP violation; CKM matrix; lepton flavor violation ID CHIRAL PERTURBATION-THEORY; LIQUID KRYPTON CALORIMETER; DIRECT CP VIOLATION; KOBAYASHI-MASKAWA MATRIX; ENDCAP PHOTON DETECTOR; MHZ-PIPELINED TRIGGER; CERN NA48 EXPERIMENT; BRANCHING RATIO; UPPER LIMIT; LEADING LOGARITHMS AB We review the current status of the field of rare kaon decays. The study of rare kaon decays has played a key role in the development of the standard model, and the field continues to have significant impact. The two areas of greatest import are the search for physics beyond the standard model and the determination of fundamental standard-model parameters. Due to the exquisite sensitivity of rare kaon decay experiments, searches for new physics can probe very high mass scales. Studies of the K --> pi nu<()over bar>modes in particular, where the first event has recently been seen, will permit tests of the standard-model picture of quark mixing and CP violation. C1 Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Barker, AR (reprint author), Univ Colorado, Dept Phys, Boulder, CO 80309 USA. EM tonyb@cuhep.colorado.edu; kettell@bnl.gov NR 263 TC 30 Z9 30 U1 0 U2 0 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0163-8998 J9 ANNU REV NUCL PART S JI Annu. Rev. Nucl. Part. Sci. PY 2000 VL 50 BP 249 EP 297 DI 10.1146/annurev.nucl.50.1.249 PG 57 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387LL UT WOS:000166124000008 ER PT J AU Verbaarschot, JJM Wettig, T AF Verbaarschot, JJM Wettig, T TI Random matrix theory and chiral symmetry in QCD SO ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE LA English DT Review DE effective low-energy theories; finite volume partition function; lattice QCD ID VOLUME PARTITION-FUNCTIONS; LATTICE GAUGE-THEORY; SPECTRAL SUM-RULES; HERMITIAN RANDOM MATRICES; STRONG-COUPLING ANALYSIS; DIRAC OPERATOR SPECTRUM; EXACTLY MASSLESS QUARKS; NONZERO BARYON DENSITY; ART. NO. 054501; LARGE-N AB Random matrix theory is a powerful way to describe universal correlations of eigenvalues of complex systems. It also may serve as a schematic model for disorder in quantum systems. In this review, we discuss both types of applications of chiral random matrix theory to the QCD partition function. We show that constraints imposed by chiral symmetry and its spontaneous breaking determine the structure of low-energy effective partition functions for the Dirac spectrum. We thus derive exact results for the low-lying eigenvalues of the QCD Dirac operator. We argue that the statistical properties of these eigenvalues are universal and can be described by a random matrix theory with the global symmetries of the QCD partition function. The total number of such eigenvalues increases with the square root of the Euclidean four-volume. The spectral density for larger eigenvalues Glut still well below a typical hadronic mass scale) also follows from the same low-energy effective partition function. The validity of the random matrix approach has been confirmed by many lattice QCD simulations in a wide parameter range. Stimulated by the success of the chiral random matrix theory in the description of universal properties of the Dirac eigenvalues, the random matrix model is extended to nonzero temperature and chemical potential. In this way we obtain qualitative results for the QCD phase diagram and the spectrum of the QCD Dirac operator. We discuss the nature of the quenched approximation and analyze quenched Dirac spectra at nonzero baryon density in terms of an effective partition function. Relations with other fields are also discussed. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. EM verbaarschot@nuclear.physics.sunysb.edu; tilo.wettig@yale.edu NR 301 TC 195 Z9 195 U1 0 U2 4 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0163-8998 J9 ANNU REV NUCL PART S JI Annu. Rev. Nucl. Part. Sci. PY 2000 VL 50 BP 343 EP 410 DI 10.1146/annurev.nucl.50.1.343 PG 68 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387LL UT WOS:000166124000010 ER PT J AU Bunce, G Saito, N Soffer, J Vogelsan, W AF Bunce, G Saito, N Soffer, J Vogelsan, W TI Prospects for spin physics at RHIC SO ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE LA English DT Review DE proton spin structure; spin asymmetries; quantum chromodynamics; beyond the standard model ID TO-LEADING-ORDER; PROTON-PROTON COLLISIONS; PROMPT-PHOTON PRODUCTION; DEEP-INELASTIC-SCATTERING; ORBITAL-ANGULAR-MOMENTUM; DRELL-YAN-PROCESS; POLARIZED PP COLLISIONS; LAMBDA-BARYON PRODUCTION; LEPTON-PAIR PRODUCTION; INTERFERENCE FRAGMENTATION FUNCTIONS AB Colliding beams of 70% polarized protons at up to roots = 500 GeV, with high luminosity, L = 2 X 10(32) cm(-2) sec(-1), will represent a new and unique laboratory for studying the proton. RHIC-Spin will be the first polarized-proton collider and will be capable of copious production of jets, directly produced photons, and W and Z bosons. Features will include direct and precise measurements of the polarization of the gluons and of (u) over bar, (d) over bar, u, and d quarks in a polarized proton. Parity violation searches for physics beyond the standard model will be competitive with unpolarized searches at the Fermilab Tevatron. Transverse spin will explore transversity for the first time, as well as quark-gluon correlations in the proton. Spin dependence of the total cross section and in the Coulomb nuclear interference region will be measured at collider energies for the first time. These qualitatively new measurements can be expected to deepen our understanding of the structure of matter and of the strong interaction. C1 Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. CNRS, Ctr Phys Theor, F-13288 Marseille 9, France. SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. RP Bunce, G (reprint author), Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. EM bunce@bnl.gov; saito@bnl.gov; Jacques.Soffer@cpt.univ-mrs.fr; wvogelsang@bnl.gov NR 259 TC 288 Z9 288 U1 0 U2 0 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0163-8998 J9 ANNU REV NUCL PART S JI Annu. Rev. Nucl. Part. Sci. PY 2000 VL 50 BP 525 EP 575 DI 10.1146/annurev.nucl.50.1.525 PG 51 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387LL UT WOS:000166124000013 ER PT J AU Hinchliffe, I Manohar, A AF Hinchliffe, I Manohar, A TI The QCD coupling constant SO ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE LA English DT Review DE jets; tau-decay; deep inelastic scattering ID DEEP-INELASTIC-SCATTERING; PHOTON STRUCTURE-FUNCTION; TO-LEADING ORDER; STRUCTURE-FUNCTION F-2(GAMMA); DEUTERON STRUCTURE FUNCTIONS; STRUCTURE-FUNCTION G(1)(P); HADRONIC EVENT SHAPES; JET CROSS-SECTIONS; SMITH SUM-RULE; E+E-ANNIHILATION AB This paper presents a summary of the current status of determinations of the strong coupling constant alpha (s). A. detailed description of the definition, scale dependence, and inherent theoretical ambiguities is given. The various physical processes that can be used to determine alpha (s) are reviewed and attention is given to the uncertainties, both theoretical and experimental. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Hinchliffe, I (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. EM I_Hinchliffe@lbl.gov; amanohar@ucsd.edu NR 194 TC 15 Z9 15 U1 0 U2 2 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0163-8998 J9 ANNU REV NUCL PART S JI Annu. Rev. Nucl. Part. Sci. PY 2000 VL 50 BP 643 EP 678 DI 10.1146/annurev.nucl.50.1.643 PG 36 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387LL UT WOS:000166124000015 ER PT J AU Hall, GE North, SW AF Hall, GE North, SW TI Transient laser frequency modulation spectroscopy SO ANNUAL REVIEW OF PHYSICAL CHEMISTRY LA English DT Review DE radical spectroscopy; kinetics; Doppler spectroscopy; photodissociation dynamics ID POTENTIAL-ENERGY SURFACES; PULSED DYE-LASER; PHOTODISSOCIATION DYNAMICS; VECTOR CORRELATIONS; ABSORPTION-SPECTROSCOPY; FM SPECTROSCOPY; LINE-SHAPES; HETERODYNE SPECTROSCOPY; UNIMOLECULAR REACTIONS; NM PHOTODISSOCIATION AB Explicitly time-dependent implementations of optical frequency modulation spectroscopy have been recently applied to a wide range of problems in chemical physics. We provide a brief description of the methodology, with an emphasis on its intrinsic advantages for interrogating transient species. Several examples highlight the application of the technique to high-resolution absorption spectra of free radicals, rate measurements for gas-phase reactions, and Doppler spectroscopy of the gas-phase products of photoinitiated reactions. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Texas A&M Univ, Dept Chem, College Stn, TX 77842 USA. RP Hall, GE (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI North, Simon/G-5054-2012; Hall, Gregory/D-4883-2013 OI North, Simon/0000-0002-0795-796X; Hall, Gregory/0000-0002-8534-9783 NR 89 TC 47 Z9 51 U1 6 U2 21 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0066-426X J9 ANNU REV PHYS CHEM JI Annu. Rev. Phys. Chem. PY 2000 VL 51 BP 243 EP 274 DI 10.1146/annurev.physchem.51.1.243 PG 34 WC Chemistry, Physical SC Chemistry GA 379YN UT WOS:000165670900010 PM 11031282 ER PT J AU Wall, ME Gallagher, SC Trewhella, J AF Wall, ME Gallagher, SC Trewhella, J TI Large-scale shape changes in proteins and macromolecular complexes SO ANNUAL REVIEW OF PHYSICAL CHEMISTRY LA English DT Review DE protein dynamics; conformational change; small-angle X-ray and neutron scattering; enzyme activation; kinase regulation ID X-RAY-SCATTERING; LIGHT-CHAIN KINASE; SMALL-ANGLE SCATTERING; ESCHERICHIA-COLI RUVA; METHYLOSINUS-TRICHOSPORIUM OB3B; METHYLOCOCCUS-CAPSULATUS-BATH; CATALYTIC SUBUNIT; CRYSTAL-STRUCTURE; NEUTRON-SCATTERING; METHANE MONOOXYGENASE AB Proteins and RNA undergo intricate motions as they carry out functions in biological systems. These motions frequently entail large-scale conformational changes that induce changes in the surface structure, or shape, of a molecule. This review describes the experimental characterization of large-scale shape changes in proteins and macromolecular complexes and the effects of such changes on macromolecular behavior. We describe several important results that have been obtained by using small-angle scattering, which is emerging as a powerful technique for determining macromolecular shapes and elucidating the quaternary structure of macromolecular assemblies. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. RP Wall, ME (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, POB 1663, Los Alamos, NM 87545 USA. RI huang, hongqi/N-1473-2014; OI Trewhella, Jill/0000-0002-8555-6766 FU NIGMS NIH HHS [GM40528] NR 110 TC 44 Z9 44 U1 2 U2 7 PU ANNUAL REVIEWS PI PALO ALTO PA 4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139 USA SN 0066-426X J9 ANNU REV PHYS CHEM JI Annu. Rev. Phys. Chem. PY 2000 VL 51 BP 355 EP 380 DI 10.1146/annurev.physchem.51.1.355 PG 26 WC Chemistry, Physical SC Chemistry GA 379YN UT WOS:000165670900014 PM 11031286 ER PT B AU Lipkin, J Whinnery, LR Griffiths, S Nilson, R Kaminska, J Mower, G Munson, W McNair, J Elliott, J AF Lipkin, J Whinnery, LR Griffiths, S Nilson, R Kaminska, J Mower, G Munson, W McNair, J Elliott, J BE Machacek, O TI Application of cryocycling to rocket motor propellant size reduction and reuse SO APPLICATION OF DEMILITARIZED GUN AND ROCKET PROPELLANTS IN COMMERCIAL EXPLOSIVES SE NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Application of Demilitarized Gun and Rocket Propellants in Commercial Explosives CY OCT 18-21, 1999 CL KRASNOARMEISK, RUSSIA SP NATO Sci Advisory Comm C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Lipkin, J (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6697-2 J9 NATO SCI SER II MATH PY 2000 VL 3 BP 35 EP 35 PG 1 WC Chemistry, Applied; Engineering, Chemical; Engineering, Industrial SC Chemistry; Engineering GA BR92Y UT WOS:000168052400006 ER PT B AU Mitchell, AR Coburn, MD Schmidt, RD Pagoria, PF Lee, GS AF Mitchell, AR Coburn, MD Schmidt, RD Pagoria, PF Lee, GS BE Machacek, O TI Conversion of demilitarized explosives and propellants to higher value products SO APPLICATION OF DEMILITARIZED GUN AND ROCKET PROPELLANTS IN COMMERCIAL EXPLOSIVES SE NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Application of Demilitarized Gun and Rocket Propellants in Commercial Explosives CY OCT 18-21, 1999 CL KRASNOARMEISK, RUSSIA SP NATO Sci Advisory Comm ID VICARIOUS NUCLEOPHILIC-SUBSTITUTION; BENZENEHEXAMINE; AMINATION; HYDROGEN C1 Univ Calif Lawrence Livermore Natl Lab, Energet Mat Ctr, Livermore, CA 94550 USA. RP Mitchell, AR (reprint author), Univ Calif Lawrence Livermore Natl Lab, Energet Mat Ctr, POB 808,MS L-282, Livermore, CA 94550 USA. NR 21 TC 10 Z9 10 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-6697-2 J9 NATO SCI SER II MATH PY 2000 VL 3 BP 49 EP 57 PG 5 WC Chemistry, Applied; Engineering, Chemical; Engineering, Industrial SC Chemistry; Engineering GA BR92Y UT WOS:000168052400008 ER PT S AU Stroud, PD AF Stroud, PD BE Priddy, KL Keller, PE Fogel, DB TI Kalman extension of the genetic algorithm SO APPLICATIONS AND SCIENCE OF COMPUTATIONAL INTELLIGENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 3rd Annual Conference on Applications and Science of Computational Intelligence CY APR 24-27, 2000 CL ORLANDO, FL SP SPIE ID FILTERS AB In typical GA application, the fitness assigned to a chromosome-represented individual in the context of a specified environment takes a deterministic calculable value. In many problems of interest, the fitness of an individual is stochastic, and the environment changes in unpredictable ways. These two factors contribute to an uncertainty that can be associated with the estimated fitness of the individual. The Kalman formulation provides a mechanism for a useful treatment of uncertainty within the GA framework. It provides for tracking the best-estimated fitness, and for assessing the uncertainty of the best-estimated fitness. The stochastic uncertainty of an existing individual can be reduced by additional evaluation of the fitness. The process (environmental) noise causes an increase in uncertainty as the age of the last evaluation increases. In a Kalman-extended genetic algorithm, we want to know the value of re-evaluating an existing solution in the population relative to generating and evaluating new individuals. A scheme for efficient allocation of computational resources among existing individuals and new individuals is developed. This Kalman-Darwin formulation is applied to the problem of maintaining an optimal. network configuration of links between moving nodes, with time-dependent, stochastic blockages. The nodes, for example, could be environmental sensors with radio transmitter/relays located on vehicles, and the network is configured to provide communication paths from each sensor back to a central node with minimum message loss. As the sensors move, the optimal network changes, but information contained within the GA population of solutions allows new optima to be efficiently obtained. The performance of this approach is explored and results are presented. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Stroud, PD (reprint author), Univ Calif Los Alamos Natl Lab, MS-F607, Los Alamos, NM 87545 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3681-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4055 BP 176 EP 187 DI 10.1117/12.380570 PG 12 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications SC Computer Science GA BQ19C UT WOS:000087421200019 ER PT S AU Kercel, SW Klein, MB Pouet, B AF Kercel, SW Klein, MB Pouet, B BE Priddy, KL Keller, PE Fogel, DB TI Bayesian separation of Lamb wave signatures in laser ultrasonics SO APPLICATIONS AND SCIENCE OF COMPUTATIONAL INTELLIGENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 3rd Annual Conference on Applications and Science of Computational Intelligence CY APR 24-27, 2000 CL ORLANDO, FL SP SPIE DE laser-based ultrasonic; weld inspection; on-line inspection; Bayesian; separation AB Laser-based ultrasonic (LBU) measurement shows great promise for on-line monitoring of weld quality in tailor-welded blanks. Tailor-welded blanks are steel blanks made from plates of differing thickness and/or properties butt-welded together; they are used in automobile manufacturing to produce body, frame, and closure panels. LBU uses a pulsed laser to generate the ultrasound and a continuous wave (CW) laser interferometer to detect the ultrasound at the point of interrogation to perform ultrasonic inspection. LBU enables in-process measurements since there is no sensor contact or near-contact with the workpiece. The authors are using laser-generated plate (Lamb) waves to propagate from one plate into the weld nugget as a means of detecting defects. A persistent problem in the analysis of Lamb wave signatures in experimental data is the fact that several different modes appear simultaneously in the signal. The modes overlap in both frequency and time domains. Attempts to separate the overlapping Lamb wave signatures by conventional signal processing methods have been unsatisfactory. This paper reports an exciting alternative to conventional methods. Severely overlapping Lamb waves are found to be readily separable by Bayesian parameter estimation. The authors have used a linear-chirped Gaussian-windowed sinusoid as a model of the Lamb wave mode. For signatures captured in laser ultrasonic data in tailor-welded blanks, this has led to straightforward separation of multiple modes. Furthermore, the resulting parameter sets for the different modes reveal crucial characterizing features of the properties of the workpiece. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Kercel, SW (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI CHEN, Jiangang/A-1549-2011 NR 13 TC 5 Z9 5 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3681-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4055 BP 350 EP 361 DI 10.1117/12.380588 PG 12 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications SC Computer Science GA BQ19C UT WOS:000087421200035 ER PT S AU Kelsey, RL Webster, RB AF Kelsey, RL Webster, RB BE Priddy, KL Keller, PE Fogel, DB TI Analyzing use cases for knowledge acquisition SO APPLICATIONS AND SCIENCE OF COMPUTATIONAL INTELLIGENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 3rd Annual Conference on Applications and Science of Computational Intelligence CY APR 24-27, 2000 CL ORLANDO, FL SP SPIE DE object-based knowledge representation; knowledge acquisition; use-case analysis; intelligent agents AB The analysis of use cases describing construction of simulation configuration files in a data/information management system can lead to the acquisition of new information and knowledge. In this application, a user creates a use case with an extensible Markup Language (XML) description representing a configuration file for simulation of a physical system. Intelligent agents analyze separate versions of the XML descriptions of a user and additionally, make comparisons of the descriptions with examples from a library of use cases. The agents can then make recommendations to a user on how to proceed or if tutoring is necessary. In a proof-of-concept test, new information is acquired and a user learns from the agent-facilitated tutoring. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kelsey, RL (reprint author), Univ Calif Los Alamos Natl Lab, C-8 MS-F645, Los Alamos, NM 87545 USA. NR 11 TC 3 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3681-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4055 BP 384 EP 391 DI 10.1117/12.380591 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications SC Computer Science GA BQ19C UT WOS:000087421200038 ER PT S AU Allgood, GO Upadhyaya, BR AF Allgood, GO Upadhyaya, BR BE Priddy, KL Keller, PE Fogel, DB TI A model-based high-frequency matched filter arcing diagnostic system based on principal component analysis (PCA) clustering SO APPLICATIONS AND SCIENCE OF COMPUTATIONAL INTELLIGENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 3rd Annual Conference on Applications and Science of Computational Intelligence CY APR 24-27, 2000 CL ORLANDO, FL SP SPIE DE DC motor diagnostics; incipient/entrained arc detection; matched filter model; prognostics and health assessment; principal component analysis AB Arcing in high-energy systems can have a detrimental effect on the operational performance, energy efficiency, life cycle and operating and support costs of a facility. It can occur in motors, switching networks, and transformers and can pose a serious threat to humans who operate or work around the systems. To reduce this risk and increase operational efficiency, it is necessary to develop a capability to diagnose single and multiple arcing events in order to provide an effective measure (or grading) of system performance. This calculated parameter can then be used to provide an effective measure of system health as it relates to arcing and its deleterious effects. This paper details the development of a model-based matched filter for an antenna that recognizes single and/or multiple arcing events in a direct current (DC) motor and calculates a functional measure of activity and a confidence factor based on a estimate of how well the data fit the matched filter model parameters. A principal component analysis is then performed on the descriptive statistics calculated from the model's output data stream to develop cluster centers for classifying non-arcing and arcing events that are invariant to system operating set point. This approach also has a deployment benefit in that the PCA decreases the computational load on the classifier system by reducing the order of the system. A similar model was developed for a magnetic field probe. This paper details the work and results for the antenna only. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Allgood, GO (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 1 TC 1 Z9 1 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3681-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4055 BP 430 EP 440 DI 10.1117/12.380597 PG 11 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications SC Computer Science GA BQ19C UT WOS:000087421200043 ER PT S AU Allred, LG Jones, MH Sheats, MJ Davis, AW AF Allred, LG Jones, MH Sheats, MJ Davis, AW BE Priddy, KL Keller, PE Fogel, DB TI Computed tomography of x-ray images using neural networks SO APPLICATIONS AND SCIENCE OF COMPUTATIONAL INTELLIGENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 3rd Annual Conference on Applications and Science of Computational Intelligence CY APR 24-27, 2000 CL ORLANDO, FL SP SPIE AB Traditional Computed Tomography (CT) reconstruction is done using the technique of Filtered Backprojection. While this technique is widely employed in industrial and medical applications, it is not generally understood that Filtered Backprojection has a fundamental flaw. Gibbs phenomena states any Fourier reconstruction (which includes Filtered Backprojection) will produce errors in the vicinity of all discontinuities, and that the error will equal 28% of the discontinuity. A number of years back, one of the authors proposed a biological perception model whereby biological neural networks perceive 3-dimensional images from stereo vision. The perception model proports an internal hard-wired neural network which emulates the external physical process. A process is repeated whereby erroneous unknown internal values are used to generate an emulated signal with is compared to external sensed data, generating an error signal. Feedback from the error signal is then used to update the erroneous internal values. The process is repeated until the error signal no longer decreases. It was soon realized that the same method could be used to obtain Computed Tomography from x-rays without having to do Fourier transforms. Neural networks have the additional potential for handling non-linearities and missing data. The technique has been applied to some coral images, collected at the Los Alamos high-energy x-ray facility. The initial images show considerable promise, in some instances showing more detail than the Filtered Backprojection images obtained from the same data. Although routine production using this new method would require a massively parallel computer, the method shows promise, especially where refined detail is required. C1 Univ Calif Los Alamos Natl Lab, ESA MT, Los Alamos, NM 87545 USA. RP Allred, LG (reprint author), Univ Calif Los Alamos Natl Lab, ESA MT, Los Alamos, NM 87545 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3681-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4055 BP 460 EP 468 DI 10.1117/12.380600 PG 9 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications SC Computer Science GA BQ19C UT WOS:000087421200046 ER PT S AU Keller, PE McMakin, DL Sheen, DM McKinnon, AD Summet, JW AF Keller, PE McMakin, DL Sheen, DM McKinnon, AD Summet, JW BE Priddy, KL Keller, PE Fogel, DB TI Privacy algorithm for airport passenger screening portal SO APPLICATIONS AND SCIENCE OF COMPUTATIONAL INTELLIGENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 3rd Annual Conference on Applications and Science of Computational Intelligence CY APR 24-27, 2000 CL ORLANDO, FL SP SPIE DE airport security; weapons detection; neural networks; millimeter wave imagery; privacy AB A novel personnel surveillance system has been developed for airport security to detect and identify threatening objects, which are concealed on the human body. The main advantage of this system over conventional metal detectors is that nonmetallic objects such as plastic explosives and plastic guns are detectable. This system is based on millimeter-wave array technology and a holographic imaging algorithm to provide surveillance images of objects hidden beneath clothing in near real-time. The privacy algorithm is based on image processing filters and artificial neural networks. The algorithm examines the millimeter-wave surveillance images to locate and segment the threats and place them on either a silhouette of the person or a wire-frame humanoid representation. In this way, all human features are removed from the final image and personal privacy is maintained. This system is ideally suited for mass transportation centers such as airport checkpoints that require high throughput rates. The system is currently under going evaluation. This paper reports on results from an earlier initial test of portions of the privacy algorithm that detect hidden plastic objects. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Keller, PE (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. OI McKinnon, Archibald/0000-0002-3963-783X NR 12 TC 2 Z9 2 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3681-X J9 P SOC PHOTO-OPT INS PY 2000 VL 4055 BP 476 EP 483 DI 10.1117/12.380602 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications SC Computer Science GA BQ19C UT WOS:000087421200048 ER PT S AU Skourikhine, AN Prasad, L Schlei, BR AF Skourikhine, AN Prasad, L Schlei, BR BE Bosacchi, B Fogel, DB Bezdek, JC TI Neural network for image segmentation SO APPLICATIONS AND SCIENCE OF NEURAL NETWORKS, FUZZY SYSTEMS, AND EVOLUTIONARY COMPUTATION III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Applications and Science of Neural Networks, Fuzzy Systems, and Evolutionary Computation III CY JUL 31-AUG 01, 2000 CL SAN DIEGO, CA SP SPIE, Soc Ind & Appl Math DE pulse-coupled neural network; PCNN; image processing; segmentation; smoothing; granular materials AB Image analysis is an important requirement of many artificial intelligence systems. Though great effort has been devoted to inventing efficient algorithms far image analysis, there is still much work to be done. It is natural to turn to mammalian vision systems for guidance because they are the best known performers of visual tasks. The pulse-coupled neural network (PCNN) model of the cat visual cortex has proven to have interesting properties for image processing. This article describes the PCNN application to the processing of images of heterogeneous materials; specifically PCNN is applied to image denoising and image segmentation. Our results show that PCNNs do well at segmentation if we perform image smoothing prior to segmentation. We use PCNN for both smoothing and segmentation. Combining smoothing and segmentation enable us to eliminate PCNN sensitivity to the setting of the various PCNN parameters whose optimal selection can be difficult and can vary even for the same problem. This approach makes image processing based on PCNN more automatic in our application and also results in better segmentation. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Skourikhine, AN (reprint author), Univ Calif Los Alamos Natl Lab, MS E541, Los Alamos, NM 87545 USA. NR 8 TC 6 Z9 6 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3765-4 J9 P SOC PHOTO-OPT INS PY 2000 VL 4120 BP 28 EP 35 DI 10.1117/12.403632 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA BR08W UT WOS:000165615400005 ER PT S AU Perkins, S Theiler, J Brumby, SP Harvey, NR Porter, R Szymanski, JJ Bloch, JJ AF Perkins, S Theiler, J Brumby, SP Harvey, NR Porter, R Szymanski, JJ Bloch, JJ BE Bosacchi, B Fogel, DB Bezdek, JC TI GENIE: A hybrid genetic algorithm for feature classification in multi-spectral images SO APPLICATIONS AND SCIENCE OF NEURAL NETWORKS, FUZZY SYSTEMS, AND EVOLUTIONARY COMPUTATION III SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Applications and Science of Neural Networks, Fuzzy Systems, and Evolutionary Computation III CY JUL 31-AUG 01, 2000 CL SAN DIEGO, CA SP SPIE, Soc Ind & Appl Math DE genetic algorithms; genetic programming; hybrid genetic algorithms; image feature classification; remote sensing; spatial context AB We consider the problem of pixel-by-pixel classification of a multi-spectral image using supervised learning. Conventional supervised classification techniques such as maximum likelihood classification and less conventional ones such as neural networks, typically base such classifications solely on the spectral components of each pixel. It is easy to see why: the color of a pixel provides a nice, bounded, fixed dimensional space in which these classifiers work well. It is often the case however, that spectral information alone is not sufficient to correctly classify a pixel. Maybe spatial neighborhood information is required as well. Or maybe the raw spectral components do not themselves make for easy classification, but some arithmetic combination of them would. In either of these cases ae have the problem of selecting suitable spatial, spectral or spatio-spectral features that allow the classifier to do its job well. The number of all possible such features is extremely large. Row can we select a suitable subset? We have developed GENIE, a hybrid learning system that combines a genetic algorithm that searches a space of image processing operations for a set that can produce suitable feature planes, and a more conventional classifier which uses those feature planes to output a final classification. In this paper we show that the use of a hybrid GA provides significant advantages over using either a GA alone or more conventional classification methods alone. We present results using high-resolution IKONOS data, looking for regions of burned forest and for roads. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM s.perkins@lanl.gov NR 11 TC 30 Z9 30 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3765-4 J9 PROC SPIE PY 2000 VL 4120 BP 52 EP 62 DI 10.1117/12.403635 PG 11 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA BR08W UT WOS:000165615400008 ER PT S AU Cantu-Paz, E Kamath, C AF Cantu-Paz, E Kamath, C BE Bosacchi, B Fogel, DB Bezdek, JC TI Combining evolutionary algorithms with oblique decision trees to detect bent-double galaxies SO APPLICATIONS AND SCIENCE OF NEURAL NETWORKS, FUZZY SYSTEMS, AND EVOLUTIONARY COMPUTATION III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Applications and Science of Neural Networks, Fuzzy Systems, and Evolutionary Computation III CY JUL 31-AUG 01, 2000 CL SAN DIEGO, CA SP SPIE, Soc Ind & Appl Math DE classification; decision trees; oblique decision trees; evolutionary algorithms; data mining ID RADIO AB Decision trees have long been popular in classification as they use simple and easy-to-understand tests at each node. Most variants of decision trees test a single attribute at a node, leading to axis-parallel trees, where the test results in a hyperplane which is parallel to one of the dimensions in the attribute space. These trees can be rather large and inaccurate in cases where the concept to be learned is best approximated by oblique hyperplanes. In such cases, it may be more appropriate to use an oblique decision tree, where the decision at each node is a linear combination of the attributes. Oblique decision trees have not gained wide popularity in part due to the complexity of constructing good oblique splits and the tendency of existing splitting algorithms to get stuck in local minima. Several alternatives have been proposed to handle these problems including randomization in conjunction with deterministic hill-climbing and the use of simulated annealing. In this paper, we use evolutionary algorithms (EAs) to determine the split. EAs are well suited for this problem because of their global search properties, their tolerance to noisy fitness evaluations, and their scalability to large dimensional search spaces. We demonstrate our technique on a synthetic data set, and then we apply it to a practical problem from astronomy, namely, the classification of galaxies with a bent-double morphology. In addition, we describe our experiences with several split evaluation criteria. Our results suggest that, in some cases, the evolutionary approach is faster and more accurate than existing oblique decision tree algorithms. However, for our astronomical data, the accuracy is not significantly different than the axis-parallel trees. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Kamath, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, POB 808,L-561, Livermore, CA 94551 USA. NR 11 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3765-4 J9 P SOC PHOTO-OPT INS PY 2000 VL 4120 BP 63 EP 71 DI 10.1117/12.403609 PG 9 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA BR08W UT WOS:000165615400009 ER PT S AU Allred, LG AF Allred, LG BE Nasrabadi, NM Katsaggelos, AK TI Eddy current modeling using neural networks SO APPLICATIONS OF ARTIFICIAL NEURAL NETWORKS IN IMAGE PROCESSING V SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Applications of Artificial Neural Networks in Image Processing V CY JAN 27-28, 2000 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, SPIE AB There is a considerable history of using Eddy Current measurements for inspecting metal surfaces. The interpretation of the results, however, has been somewhat subjective. The sensitivity of the Eddy Current measurement to changes in material thickness is easily demonstrated. However, the reconstruction of thickness from the measurements (with any degree of confidence) has remained elusive. Part of the issue is the additional sensitivity of Eddy Current measurements to Lift distance and local geometry. This project is a culmination of an feasibility study to see if Neural Networks could provide estimates of material thicknesses for thin materials (<0.15 inches or 4 mm) for metals with low conductivity (similar to 0.7 x mega / Ohm cm). The study a neural network model, whose accuracy varies depending upon the conditions. It turns out that the conditions required for good accuracy are usually not the conditions one wants to take measurements. The model not only suggests why this problem has been unwieldy, but also suggests that most of the difficulties could be alleviated by using an independent source to measure the Lift distance. C1 Los Alamos Natl Lab, Measurement Technol ESA MT, Los Alamos, NM 87544 USA. RP Los Alamos Natl Lab, Measurement Technol ESA MT, POB 1663, Los Alamos, NM 87544 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3580-5 J9 PROC SPIE PY 2000 VL 3962 BP 216 EP 223 DI 10.1117/12.382915 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Optics SC Computer Science; Optics GA BQ23B UT WOS:000087646500022 ER PT S AU Brown, PN Chang, B Hanebutte, UR Woodward, CS AF Brown, PN Chang, B Hanebutte, UR Woodward, CS BE Ingber, M Power, H Brebbia, CA TI The quest for a high performance Boltzmann transport solver SO APPLICATIONS OF HIGH-PERFORMANCE COMPUTING IN ENGINEERING VI SE ADVANCES IN HIGH PERFORMANCE COMPUTING (SERIES) LA English DT Proceedings Paper CT 6th International Conference on Applications of High-Performance Computing in Engineering CY JAN 26-28, 2000 CL MAUI HIGH PERFORMANCE COMP CTR, MAUI, HI SP Univ New Mexico, Wessex Inst Technol HO MAUI HIGH PERFORMANCE COMP CTR AB A 3-d Boltzmann transport code developed at Lawrence Livermore National Laboratory exploits concurrency (problem permitting) with respect to all phase space variables represented by direction, position and energy. To demonstrate the capabilities of the code, a highly resolved Boltzmann transport calculation with 27.6 billion unknowns (332 billion discretization points) was performed on 4992 processors of the IBM RS/6000 SP ASCI Blue machine at Lawrence Livermore National Laboratory. Detailed performance measurements were collected during this calculation. Analyzing the timing data revealed a relatively modest performance, i.e. obtained fraction of peak performance. A detailed study of the performance data confirmed that this modest performance was caused by low utilization of local processor performance, as well as low parallel efficiency of the intrinsically sequential sweep procedure. Both issues and their ramifications will be addressed in this paper. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Brown, PN (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RI Woodward, Carol/M-4008-2014 NR 9 TC 0 Z9 0 U1 0 U2 1 PU WIT PRESS PI SOUTHAMPTON PA ASHURST LODGE, SOUTHAMPTON SO40 7AA, ASHURST, ENGLAND SN 1368-7638 BN 1-85312-810-4 J9 ADV HIGH PERF COM S PY 2000 VL 6 BP 91 EP 101 PG 3 WC Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BQ22S UT WOS:000087616700010 ER PT S AU Baer, TA Subia, SR Sackinger, PA AF Baer, TA Subia, SR Sackinger, PA BE Ingber, M Power, H Brebbia, CA TI Parallel simulation of three-dimensional free-surface fluid flow problems SO APPLICATIONS OF HIGH-PERFORMANCE COMPUTING IN ENGINEERING VI SE ADVANCES IN HIGH PERFORMANCE COMPUTING (SERIES) LA English DT Proceedings Paper CT 6th International Conference on Applications of High-Performance Computing in Engineering CY JAN 26-28, 2000 CL MAUI HIGH PERFORMANCE COMP CTR, MAUI, HI SP Univ New Mexico, Wessex Inst Technol HO MAUI HIGH PERFORMANCE COMP CTR ID STOKES PROBLEM; FORMULATION AB We describe parallel simulations of viscous, incompressible, free surface, Newtonian fluid flow problems that include dynamic contact, lines. The Galerkin finite element method was used to discretize the fully-coupled governing conservation equations and a "pseudo-solid" mesh mapping approach was used to determine the shape of the free surface. In this approach, the finite element mesh is allowed to deform to satisfy quasi-static solid mechanics equations subject to geometric or kinematic constraints on the boundaries. As a result, nodal displacements must be included in the set of problem unknowns. Issues concerning the proper constraints along the solid-fluid dynamic contact line in three dimensions are discussed. Parallel computations are carried out for an example taken from the coating flow industry, flow in the vicinity of a slot coater edge. This is a three-dimensional free-surface problem possessing a contact line that advances at the web speed in one region but transitions to static behavior in another part of the flow domain. Discussion focuses on parallel speedups for fixed problem size, a class' of problems of immediate practical importance. C1 Sandia Natl Labs, Incompressible Fluid Mech Dept, Livermore, CA 94550 USA. RP Baer, TA (reprint author), Sandia Natl Labs, Incompressible Fluid Mech Dept, Livermore, CA 94550 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU WIT PRESS PI SOUTHAMPTON PA ASHURST LODGE, SOUTHAMPTON SO40 7AA, ASHURST, ENGLAND SN 1368-7638 BN 1-85312-810-4 J9 ADV HIGH PERF COM S PY 2000 VL 6 BP 345 EP 357 PG 5 WC Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BQ22S UT WOS:000087616700033 ER PT B AU Robinson, DG AF Robinson, DG BE Melchers, RE Stewart, MG TI An adaptive sampling method utilizing regionalized random variables SO APPLICATIONS OF STATISTICS AND PROBABILITY, VOLS 1 AND 2: CIVIL ENGINEERING RELIABILITY AND RISK ANALYSIS LA English DT Proceedings Paper CT 8th International Conference on Applications of Statistics and Probability (ICASP 8) CY DEC 12-15, 1999 CL SYDNEY, AUSTRALIA SP Int Assoc Civil Engn Reliabil & Risk Anal, Univ Newcastle, Dept Civil, Surveying & Environm Engn AB This paper discusses research into an alternative for characterizing the reliability of complex systems. The approach is unique in two respects: it is based on a deterministic:sampling of the likelihood function and not pseudo-Monte Carlo sampling, and second, it uses a probabilistic membership function as opposed to the 'crisp' indicator function commonly used in importance sampling. In particular, the new method assumes that the true location of the limit state function is known only in probabilistic terms. The new procedure suggested in this paper also does not require identification of the limit state function or the MPP. Through the use of regionalized random variables, the response of the system is modeled as a random field, which permits probabilistic membership statements for any feasible input vector relative to the failure domain. Preliminary results indicate that the proposed method is superior to traditional as well as stratified sampling methods. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Robinson, DG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 8 TC 0 Z9 0 U1 1 U2 1 PU A A BALKEMA PUBLISHERS PI LEIDEN PA SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS BN 90-5809-086-8 PY 2000 BP 893 EP 900 PG 8 WC Engineering, Civil; Mathematics, Applied; Statistics & Probability SC Engineering; Mathematics GA BP44T UT WOS:000085163100116 ER PT S AU Sylwester, ER Hudson, EA Allen, PG AF Sylwester, ER Hudson, EA Allen, PG BE Stock, SR Mini, SM Perry, DL TI Surface interactions of actinide ions with geologic materials studied by XAFS SO APPLICATIONS OF SYNCHROTRON RADIATION TECHNIQUES TO MATERIALS SCIENCE V SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Applications of Synchrotron Radiation Techniques to Materials Science V held at the 1999 MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MA SP Mat Res Soc, Blake Ind, Lawrence Livermore Natl Lab, Chem & Mat Sci Dept, NO Illinois Univ, Grad Sch & Coll Liberal Arts & Sci ID X-RAY-ABSORPTION; URANIUM(VI) ADSORPTION; MONTMORILLONITE CLAY; AQUEOUS-SOLUTION; FINE-STRUCTURE; URANYL IONS; SILICA-GEL; EXAFS; SORPTION; FERRIHYDRITE AB We have investigated the interaction of the actinyl ion, UO22+ with silica, alumina, and montmorillonite surfaces under ambient atmosphere and aqueous conditions using X-ray Absorption Fine Structure (XAFS) Spectroscopy. In acid solution (pH similar to 3.5), the uranyl ion shows a strong interaction with the silica and alumina surfaces, and a relatively weak association with the montmorillonite surface. The extent of direct surface interaction is determined by comparing structural distortions in the equatorial bonding environment of the uranyl ion relative to the structure of a "free" uranyl aquo complex. Based on this formalism, surface complexation on silica and alumina occurs through an inner-sphere mechanism with surface oxygen atoms binding directly to the equatorial region of the uranyl ion. In contrast, sorption on montmorillonite occurs by an outer sphere mechanism in which the uranyl ion retains the simple aquo complex structure and binds to the surface via ion-exchange In near-neutral solutions (pH similar to 6), sorption on all of the materials is dominated by an inner-sphere mechanism. The formation of surface oligomeric species is also observed on silica and alumina. C1 Univ Calif Lawrence Livermore Natl Lab, Glenn T Seaborg Inst Transactinium Sci, Livermore, CA 94551 USA. RP Sylwester, ER (reprint author), Univ Calif Lawrence Livermore Natl Lab, Glenn T Seaborg Inst Transactinium Sci, L-231,POB 808, Livermore, CA 94551 USA. NR 39 TC 1 Z9 1 U1 2 U2 5 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-498-X J9 MATER RES SOC SYMP P PY 2000 VL 590 BP 9 EP 16 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied; Spectroscopy SC Materials Science; Physics; Spectroscopy GA BQ35A UT WOS:000088094100002 ER PT S AU Kropf, AJ Johnson, CS AF Kropf, AJ Johnson, CS BE Stock, SR Mini, SM Perry, DL TI In situ XAFS of the LixNi0.8Co0.2O2 cathode for lithium-ion batteries SO APPLICATIONS OF SYNCHROTRON RADIATION TECHNIQUES TO MATERIALS SCIENCE V SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Applications of Synchrotron Radiation Techniques to Materials Science V held at the 1999 MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MA SP Mat Res Soc, Blake Ind, Lawrence Livermore Natl Lab, Chem & Mat Sci Dept, NO Illinois Univ, Grad Sch & Coll Liberal Arts & Sci ID X-RAY-ABSORPTION; FINE-STRUCTURE AB The layered LiNi0.8Co0.2O2 system is being considered as a new cathode material for the lithium-ion battery. Compared with LiCoO2, the standard cathode formulation, it possesses improved electrochemical performance at a projected lower cost. In situ x-ray absorption fine-structure spectroscopy (XAFS) measurements were conducted on a cell cycled at a moderate rate and normal Li-ion operating voltages (3.0-4.1 V). The XAFS data collected at the Ni and Co edges approximately every 30 min. revealed details about the response of the cathode to Li insertion and extraction. These measurements on the LixNi0.8Co0.2O2 cathode (0.29beta phase transitions in CoMoO4 and NiMoO4. The Mo L-II- and O K-edges in XANES are very useful for probing the local symmetry of Mo atoms in mixed-metal oxides. The results of XANES and density-functional calculations (DMol3, DFT-GGA) show large changes in the splitting of the empty Mo 4d levels when going from tetrahedral to octahedral coordinations. XANES is very useful for studying the reaction of H-2, H2S and SO2 with the mixed-metal oxides. Measurements at the S K-edge allow a clear identification of S, SO2, SO3 or SO4 on the oxide surfaces. Changes in the oxidation state of molybdenum produce substantial shifts in the position of the Mo L-II- and M-III-edges. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Brito, Joaquin/F-4974-2010 NR 14 TC 1 Z9 1 U1 0 U2 7 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-498-X J9 MATER RES SOC SYMP P PY 2000 VL 590 BP 113 EP 118 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Spectroscopy SC Materials Science; Physics; Spectroscopy GA BQ35A UT WOS:000088094100016 ER PT S AU DiMasi, E Tostmann, H Ocko, BM Huber, P Shpyrko, OG Pershan, PS Deutsch, M Berman, LE AF DiMasi, E Tostmann, H Ocko, BM Huber, P Shpyrko, OG Pershan, PS Deutsch, M Berman, LE BE Stock, SR Mini, SM Perry, DL TI Resonant x-ray scattering from the surface of a dilute liquid Hg-Au alloy SO APPLICATIONS OF SYNCHROTRON RADIATION TECHNIQUES TO MATERIALS SCIENCE V SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Applications of Synchrotron Radiation Techniques to Materials Science V held at the 1999 MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MA SP Mat Res Soc, Blake Ind, Lawrence Livermore Natl Lab, Chem & Mat Sci Dept, NO Illinois Univ, Grad Sch & Coll Liberal Arts & Sci ID ATOMIC-FORCE MICROSCOPY; REFLECTIVITY; FILMS AB We present the first resonant x-ray reflectivity measurements from a liquid surface. The surface structure of the liquid Hg-Au alloy system just beyond the solubility limit of 0.14at% Au in Hg had previously been shown to exhibit a unique surface phase characterized by a low-density surface region with a complicated temperature dependence. In this paper we present reflectivity measurements neat the Au L-III edge, for 0.2at% Au in Hg at room temperature. The data are consistent with a concentration of Au in the surface region that can be no larger than about 30at%. These results rule out previous suggestions that pure Au layers segregate at the alloy surface. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP DiMasi, E (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 15 TC 4 Z9 4 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-498-X J9 MATER RES SOC SYMP P PY 2000 VL 590 BP 183 EP 188 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Spectroscopy SC Materials Science; Physics; Spectroscopy GA BQ35A UT WOS:000088094100026 ER PT S AU Freitag, A Rodriguez, JA Larese, JZ AF Freitag, A Rodriguez, JA Larese, JZ BE Stock, SR Mini, SM Perry, DL TI Experimental investigations of the interaction of SO2 with MgO SO APPLICATIONS OF SYNCHROTRON RADIATION TECHNIQUES TO MATERIALS SCIENCE V SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Applications of Synchrotron Radiation Techniques to Materials Science V held at the 1999 MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MA SP Mat Res Soc, Blake Ind, Lawrence Livermore Natl Lab, Chem & Mat Sci Dept, NO Illinois Univ, Grad Sch & Coll Liberal Arts & Sci ID MAGNESIUM-OXIDE; ADSORPTION; SURFACE AB High resolution adsorption isotherms, temperature programmed desorption (TPD), x-ray diffraction (XRD) and x-ray absorption near edge spectroscopy (XANES) methods were used to investigate the interaction of SO2 with high quality MgO powders. The results of these investigations indicate that when SO2 is deposited on MgO in monolayer quantities at temperatures near 100K both SO3 and SO4 species form that are not removed by simply pumping on the pre-dosed samples at room temperature. TPD and XANES studies indicate that heating of pre-dosed MgO samples to temperatures above 350 degrees C is required for full removal of the SO3/SO4 species. XANES measurements made as a function of film thickness indicate for coverages near monolayer completion that the SO4 species form first. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Freitag, A (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-498-X J9 MATER RES SOC SYMP P PY 2000 VL 590 BP 189 EP 194 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Spectroscopy SC Materials Science; Physics; Spectroscopy GA BQ35A UT WOS:000088094100027 ER PT S AU Larson, BC Tamura, N Chung, JS Ice, GE Budai, JD Tischler, JZ Yang, W Weiland, H Lowe, WP AF Larson, BC Tamura, N Chung, JS Ice, GE Budai, JD Tischler, JZ Yang, W Weiland, H Lowe, WP BE Stock, SR Mini, SM Perry, DL TI 3-D measurement of deformation microstructure in Al(0.2%)Mg using submicron resolution white X-ray microbeams SO APPLICATIONS OF SYNCHROTRON RADIATION TECHNIQUES TO MATERIALS SCIENCE V SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Applications of Synchrotron Radiation Techniques to Materials Science V held at the 1999 MRS Fall Meeting CY NOV 29-DEC 03, 1999 CL BOSTON, MA SP Mat Res Soc, Blake Ind, Lawrence Livermore Natl Lab, Chem & Mat Sci Dept, NO Illinois Univ, Grad Sch & Coll Liberal Arts & Sci ID STRAIN; TEXTURE; DIFFRACTION; METALS AB We have used submicron-resolution white x-ray microbeams on the MHATT-CAT beamline 7-ID at the Advanced Photon Source to develop techniques for three-dimensional investigation of the deformation microstructure in a 20% plane strain compressed Al(0.2%)Mg tri-crystal. Kirkpatrick-Baez mirrors were used to focus white radiation from an undulator to a 0.7 x 0.7 mu m(2) beam that was scanned over bi- and tri-crystal regions near the triple-junction of the tricrystal. Depth resolution along the x-ray microbeam of less than 5 microns was achieved by triangulation to the diffraction source point using images taken at a series of CCD distances from the microbeam. Computer indexing of the deformation cell structure in the bi-crystal region provided orientations of individual subgrains to similar to 0.01 degrees, making possible detailed measurements of the rotation axes between individual cells. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Larson, BC (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RI Yang, Wenge/H-2740-2012; Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 8 TC 14 Z9 14 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-498-X J9 MATER RES SOC SYMP P PY 2000 VL 590 BP 247 EP 252 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Spectroscopy SC Materials Science; Physics; Spectroscopy GA BQ35A UT WOS:000088094100035 ER PT J AU Wise, AA Kuske, CR AF Wise, AA Kuske, CR TI Generation of novel bacterial regulatory proteins that detect priority pollutant phenols SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID SP STRAIN CF600; TRANSCRIPTIONAL ACTIVATOR; PSEUDOMONAS-PUTIDA; ESCHERICHIA-COLI; AROMATIC-COMPOUNDS; GENETIC-EVIDENCE; NTRC FAMILY; DMPR; OPERON; XYLR AB The genetic systems of bacteria that have the ability to use organic pollutants as carbon and energy sources can be adapted to create bacterial biosensors for the detection of industrial pollution. The creation of bacterial biosensors is hampered by a lack of information about the genetic systems that control production of bacterial enzymes that metabolize pollutants. We have attempted to overcome this problem through modification of DmpR, a regulatory protein for the phenol degradation pathway of Pseudomonas sp. strain CF600. The phenol detection capacity of DmpR was altered by using mutagenic PCR targeted to the DmpR sensor domain. DmpR mutants were identified that both increased sensitivity to the phenolic effecters of wild-type DmpR and increased the range of molecules detected. The phenol detection characteristics of seven DmpR mutants were demonstrated through their ability to activate transcription of a lacZ reporter gene. Effecters of the DmpR derivatives included phenol, 2-chlorophenol, 2, 1-dichlorophenol, 4-chloro-3-methylphenol, 2,4-dimethylphenol, 2-nitrophenol, and 4-nitrophenol. C1 Univ Calif Los Alamos Natl Lab, Environm Mol Biol Grp, Biosci Div, Los Alamos, NM 87545 USA. RP Kuske, CR (reprint author), Univ Calif Los Alamos Natl Lab, Environm Mol Biol Grp, Biosci Div, M888, Los Alamos, NM 87545 USA. NR 41 TC 52 Z9 56 U1 0 U2 8 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD JAN PY 2000 VL 66 IS 1 BP 163 EP 169 PG 7 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 271GL UT WOS:000084585800024 PM 10618218 ER PT J AU Julien, MH Carretta, P Borsa, F AF Julien, MH Carretta, P Borsa, F TI NQR study of spin-freezing in superconducting La2-xSrxCuO4: the example of x=0.06 SO APPLIED MAGNETIC RESONANCE LA English DT Article; Proceedings Paper CT Conference on EPR, NMR and NQR in Solid State Physics - Recent Trends CY JUN 14-18, 1999 CL UNIV PISA, DEPT PHYS, PISA, ITALY HO UNIV PISA, DEPT PHYS ID HIGH-TEMPERATURE SUPERCONDUCTORS; MAGNETIC PHASE-DIAGRAM; NORMAL-STATE; LA-139 NQR; ORDER-PARAMETER; SINGLE-CRYSTALS; STRIPE ORDER; LI-7 NMR; SR; RELAXATION AB Nuclear quadrupole resonance (NQR) La-139 and Cu-63 spin-lattice relaxation rare T-l(-1) measurements in a La1.94Sr0.06CuO4 single crystal are described. Slowing-down of Cu2+ spin fluctuations is evidenced through a dramatic increase of T-139(l)-1 on cooling. While the onset of diamagnetism occurs at T-c = 8 K, T-139(l)-1 has a peak at T-g similar or equal to 5 K, when the characteristic frequency of magnetic fluctuations reaches the NQR frequency v(Q) similar or equal to 9 MHz. in agreement with a number of previous studies, these results show that the so-called "cluster spin-glass" phase persists in the superconducting regime. Issues concerning the coexistence of the two phases are discussed. C1 INFM, Unita Pavia, Dipartimento Fis A Volta, Pavia, Italy. Iowa State Univ, Ames Lab, Dept Phys & Astron, Ames, IA USA. RP Julien, MH (reprint author), Univ Grenoble 1, Spectrometrie Phys Lab, BP 87, F-38402 St Martin Dheres, France. RI Julien, Marc-Henri/A-2352-2010 NR 57 TC 3 Z9 3 U1 0 U2 2 PU SPRINGER WIEN PI WIEN PA SACHSENPLATZ 4-6, PO BOX 89, A-1201 WIEN, AUSTRIA SN 0937-9347 EI 1613-7507 J9 APPL MAGN RESON JI Appl. Magn. Reson. PY 2000 VL 19 IS 3-4 BP 287 EP 296 DI 10.1007/BF03162370 PG 10 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 401TK UT WOS:000166944200003 ER EF