FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Silin, DB Patzek, TW AF Silin, DB Patzek, TW TI Support-operators method in the identification of permeability tensor orientation SO SPE JOURNAL LA English DT Article AB The dependence of rock permeability on direction, or permeability anisotropy, is confirmed by numerous field examples. Therefore, the ability to carry out a numerical simulation of an anisotropic reservoir is very important. The support-operators method provides a conservative discretization scheme, allowing one to solve nonisotropic problems on a grid of practically arbitrary structure. Moreover, a discretization designed with the support-operators method provides a natural and convenient way of deriving and solving the adjoint system for evaluation of the gradient and second-order differential in inverse problems. After a theoretical introduction into the support-operators method, we consider an illustrative parameter-identification problem. More specifically, we evaluate the orientation angle of a nonisotropic permeability tensor in a horizontal reservoir. We assume that the principal permeabilities near a cored or otherwise logged well are already known. To accomplish this task, we need pressure measurements in monitoring wells. We consider both rectangular and curvilinear grids. In either case, the orientation angle has been recovered with a high accuracy. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. EM Dsilin@lbl.gov; patzek@patzek.berkeley.edu NR 19 TC 5 Z9 5 U1 0 U2 1 PU SOC PETROLEUM ENG PI RICHARDSON PA 222 PALISADES CREEK DR,, RICHARDSON, TX 75080 USA SN 1086-055X EI 1930-0220 J9 SPE J JI SPE J. PD DEC PY 2001 VL 6 IS 4 BP 385 EP 398 PG 14 WC Engineering, Petroleum SC Engineering GA 514AV UT WOS:000173414600005 ER PT J AU McCrea, K Parker, JS Chen, PL Somorjai, G AF McCrea, K Parker, JS Chen, PL Somorjai, G TI Surface structure sensitivity of high-pressure CO dissociation on Pt(557), Pt(100) and Pt(111) using sum frequency generation surface vibrational spectroscopy SO SURFACE SCIENCE LA English DT Article DE carbon monoxide; platinum; sum frequency generation; single crystal surfaces ID CARBON-MONOXIDE; TRANSITION-METALS; CRYSTAL-SURFACES; PLATINUM SURFACE; ADSORPTION; SPECTRA; TEMPERATURE; PHASE; CHEMISORPTION; INTERFACE AB Using sum frequency generation (SFG) surface vibrational spectroscopy, the interaction of CO and platinum single crystals was investigated at high pressure and high temperatures. Under 40 Torr of CO, the molecule was found to dissociate on Pt(1 1 1), Pt(5 5 7) and Pt(1 0 0) at 673, 548 and 500 K, respectively. The CO top site frequency was observed to shift to lower frequencies as a function of temperature. At a particular temperature, dependent on the surface structure, the SFG spectra evolved with time, indicating the surface was being modified. The observed frequency shift before CO dissociation is attributed to anharmonic coupling to the frustrated translational mode. At the temperature at which dissociation occurs, the frequency shift is attributed to surface roughening. The surface roughening is believed to result from the formation of platinum carbonyl species, which would be a driving force to extract platinum atoms from the surface lattice. For both the (1 1 1) and (1 0 0) surfaces of platinum, the crystal must be heated to a temperature at which platinum carbonyls are formed to produce step and kink sites, which are needed for dissociation. The Pt(1 1 1) surface exhibits a much higher CO dissociation temperature as compared to Pt(1 0 0) because it is the most stable surface for platinum. Pt(5 5 7) is essentially a (1 1 1) surface with steps already present in the structure, and so the crystal does not need to be heated to a temperature to produce step and kink sites necessary for CO dissociation through the production of platinum carbonyls. CO can dissociate on the existing steps of Pt(5 5 7). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, Berkeley, CA 94720 USA. RP Somorjai, G (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, Berkeley, CA 94720 USA. RI Chen, Peilin/E-2728-2010 OI Chen, Peilin/0000-0003-4154-0487 NR 34 TC 61 Z9 61 U1 0 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD DEC 1 PY 2001 VL 494 IS 3 BP 238 EP 250 DI 10.1016/S0039-6028(01)01469-8 PG 13 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 501BU UT WOS:000172663800012 ER PT J AU Chen, P Kung, KY Shen, YR Somorjai, GA AF Chen, P Kung, KY Shen, YR Somorjai, GA TI Sum frequency generation spectroscopic study of CO/ethylene coadsorption on the Pt(111) surface and CO poisoning of catalytic ethylene hydrogenation SO SURFACE SCIENCE LA English DT Article DE sum frequency generation; alkenes; chemisorption; platinum; carbon monoxide ID INFRARED REFLECTION-ABSORPTION; SIGMA-BONDED ETHYLENE; CARBON-MONOXIDE; HIGH-PRESSURE; IN-SITU; VIBRATIONAL-SPECTRA; CRYSTAL-SURFACE; ADSORPTION; ETHYLIDYNE; DEHYDROGENATION AB Surface vibrational sum frequency generation technique has been employed to investigate CO and ethylene coadsorption on the Pt(1 1 1) surfaces at CO or ethylene pressures in the 10(-7) to 400 Torr range. Ethylidyne, which was formed when ethylene adsorbed on the Pt(1 1 1) surfaces at 300 K, was partially displaced by CO and underwent orientational change losing its vibrational resonance features in the presence of high-pressure (>1 Torr) CO at 300 K. In contrast. a monolayer of CO was found to be stable on the Pt(1 1 1) surface in the presence of high-pressure ethylene (up to 35 Torr). In the presence of 3 Torr of CO, catalytic ethylene hydrogenation was poisoned due to the site blocking effect of adsorbed CO. No catalytic reactivity was observed at temperatures lower than the CO desorption temperature (400 K). Above the CO desorption temperature, the reaction turnover rate was observed to be three orders of magnitude less than the same reaction without the presence of high-pressure CO. The activation energy of the CO poisoned ethylene hydrogenation reaction is about 20.5 kcal/mol while the activation energy is 10 kcal/mol in the absence of CO. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Somorjai, GA (reprint author), Univ Calif Berkeley, Dept Chem, D58 Hildebrand Hall 1460, Berkeley, CA 94720 USA. RI Chen, Peilin/E-2728-2010 OI Chen, Peilin/0000-0003-4154-0487 NR 32 TC 41 Z9 41 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD DEC 1 PY 2001 VL 494 IS 3 BP 289 EP 297 DI 10.1016/S0039-6028(01)01512-6 PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 501BU UT WOS:000172663800016 ER PT J AU Saidy, M Warren, OL Thiel, PA Mitchell, KAR AF Saidy, M Warren, OL Thiel, PA Mitchell, KAR TI A structural refinement with LEED for the Pd(100)-(root 5 x root 5)R27 degrees-O surface SO SURFACE SCIENCE LA English DT Letter DE palladium low energy electron diffraction (LEED); low index single crystal surfaces; oxygen; surface relaxation and reconstruction AB The re-analysis with LEED for the Pd(1 0 0)-(root5 x root5)R27 degrees -O surface structure confirms the basic model, reported previously by Vu et al. [Surf. Sci. 318 (1994) 129], in which a PdO(0 0 1) overlayer is stacked on to the Pd(1 0 0) surface. The refinement reduces the Pendry R-factor to 0.306, from 0.44 in the earlier study, and the detailed structure at the metal-oxide interface shows evidence for a balancing of interactions compared with requirements for the oxide and metal separately. Pd atoms in the oxide layer have a corrugation estimated at 0.20 Angstrom, and the binding of this layer to the metal induces a substantial rumpling in the interface region, which covers especially the first and second metallic layers with corrugations of 0.45 and 0.15 Angstrom respectively. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ British Columbia, Dept Chem, Vancouver, BC V6T 1Z1, Canada. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Mitchell, KAR (reprint author), Univ British Columbia, Dept Chem, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada. NR 9 TC 29 Z9 29 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD DEC 1 PY 2001 VL 494 IS 3 BP L799 EP L804 DI 10.1016/S0039-6028(01)01544-8 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 501BU UT WOS:000172663800002 ER PT J AU Schiffer, WK Gerasimov, MR Marsteller, DA Geiger, J Barnett, C Alexoff, DL Dewey, SL AF Schiffer, WK Gerasimov, MR Marsteller, DA Geiger, J Barnett, C Alexoff, DL Dewey, SL TI Topiramate selectively attenuates nicotine-induced increases in monoamine release SO SYNAPSE LA English DT Article ID VENTRAL TEGMENTAL AREA; INDUCED DOPAMINE RELEASE; NUCLEUS-ACCUMBENS; LOCOMOTOR-ACTIVITY; LOCUS-COERULEUS; RAT; NEURONS; GABA; RECEPTORS; ADDICTION C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NYU, Sch Med, Dept Psychiat, New York, NY USA. RP Schiffer, WK (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NIDA NIH HHS [5RO-DA06278]; NIMH NIH HHS [MH49165]; PHS HHS [R2955155] NR 27 TC 46 Z9 46 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 0887-4476 J9 SYNAPSE JI Synapse PD DEC 1 PY 2001 VL 42 IS 3 BP 196 EP 198 DI 10.1002/syn.10000 PG 3 WC Neurosciences SC Neurosciences & Neurology GA 486VW UT WOS:000171838500008 PM 11746717 ER PT J AU Horstemeyer, MF Baskes, MI Plimpton, SJ AF Horstemeyer, MF Baskes, MI Plimpton, SJ TI Computational nanoscale plasticity simulations using embedded atom potentials SO THEORETICAL AND APPLIED FRACTURE MECHANICS LA English DT Article; Proceedings Paper CT 3rd International Conference on Mesomechanics CY JUN 13-16, 2000 CL XIAN, PEOPLES R CHINA ID MOLECULAR-DYNAMICS SIMULATIONS; STRAIN GRADIENT PLASTICITY; SINGLE-CRYSTALS; POLYCRYSTAL ELASTOVISCOPLASTICITY; DISLOCATION NUCLEATION; LATTICE-DEFECTS; SHOCK-WAVES; DEFORMATION; NICKEL; TORSION AB In determining structure-property relations for plasticity at different size scales, it is desired to bridge concepts from the continuum to the atom. This raises many questions related to volume averaging, appropriate length scales of focus for an analysis, and postulates in continuum mechanics. In a preliminary effort to evaluate bridging size scales and continuum concepts with descritized phenomena, simple shear molecular dynamics simulations using the Embedded Atom Method (EAM) potentials were performed on single crystals. In order to help evaluate the continuum quantities related to the kinematic and thermodynamic force variables, finite element simulations (with different material models) and macroscale experiments were also performed. In this scoping study, various parametric effects on the stress state and kinematics have been quantified. The parameters included the following: crystal orientation (single slip, double slip, quadruple slip, octal slip), temperature (300 and 500 K), applied strain rate (10(6)-10(12) s(-1)), specimen size (10 atoms to 2 mum), specimen aspect ratio size (1:8-8:1), deformation path (compression, tension, simple shear, and torsion), and material (nickel, aluminum, and copper). Although many conclusions can be drawn from this work, which has provided fodder for more studies, several major conclusions can be drawn. The yield stress is a function of a size scale parameter (volume-per-surface area) that was determined from atomistic simulations coupled with experiment;. As the size decreases, the yield stress increases. Although the thermodynamic force (stress) varies at different size scales, the kinematics of deformation appears to be very similar based on atomistic simulations, finite element simulations, and physical experiments. Atomistic simulations, that inherently include extreme strain rates and size scales, give results that agree with the phenomenological attributes of plasticity observed in macroscale experiments. These include strain rate dependence of the flow stress into a rate independent regime; approximate Schmid type behavior; size scale dependence on the flow stress, and kinematic behavior of large deformation plasticity. (C) 2001 Published by Elsevier Science Ltd. C1 Sandia Natl Labs, Ctr Mat & Engn Sci, Livermore, CA 94551 USA. Los Alamos Natl Lab, Struct Property Relat, Los Alamos, NM 87545 USA. Sandia Natl Labs, Sci Based Mat Modeling Dept, Livermore, CA 94551 USA. RP Horstemeyer, MF (reprint author), Sandia Natl Labs, Ctr Mat & Engn Sci, MS9042,7011 E Ave, Livermore, CA 94551 USA. EM mfhorst@sandia.gov OI Horstemeyer, Mark/0000-0003-4230-0063 NR 75 TC 74 Z9 76 U1 2 U2 30 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8442 J9 THEOR APPL FRACT MEC JI Theor. Appl. Fract. Mech. PD DEC PY 2001 VL 37 IS 1-3 BP 49 EP 98 DI 10.1016/S0167-8442(01)00090-8 PG 50 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 509MR UT WOS:000173152000007 ER PT J AU Klein, PA Foulk, JW Chen, EP Wimmer, SA Gao, HJ AF Klein, PA Foulk, JW Chen, EP Wimmer, SA Gao, HJ TI Physics-based modeling of brittle fracture: cohesive formulations and the application of meshfree methods SO THEORETICAL AND APPLIED FRACTURE MECHANICS LA English DT Article; Proceedings Paper CT 3rd International Conference on Mesomechanics CY JUN 13-16, 2000 CL XIAN, PEOPLES R CHINA ID FREE GALERKIN METHOD; KERNEL PARTICLE METHODS; DYNAMIC CRACK-GROWTH; FINITE-ELEMENT SIMULATION; NUMERICAL-SIMULATION; COMPRESSIVE BEHAVIOR; STRAIN LOCALIZATION; PROPAGATING CRACKS; LARGE-DEFORMATION; PLANE-STRAIN AB Simulation of generalized fracture and fragmentation remains an ongoing challenge in computational fracture mechanics. There are difficulties associated not only with the formulation of physically based models of material failure, but also with the numerical methods required to treat geometries that change in time. The issue of fracture criteria is addressed in this work through a cohesive view of materials, meaning that a finite material strength and work to fracture are included in the material description. In this study, both surface and bulk cohesive formulations are presented for modeling brittle fracture, detailing the derivation of the formulations, fitting relations, and providing a critical assessment of their capabilities in numerical simulations of fracture. Due to their inherent adaptivity and robustness under severe deformation, meshfree methods are especially well suited to modeling fracture behavior. Described are the applications of meshfree methods to both bulk and surface approaches to cohesive modeling. Numerical examples are provided to highlight the capabilities and shortcomings of the methods in order to identify which approaches are best suited to modeling different types of fracture phenomena. (C) 2001 Published by Elsevier Science Ltd. C1 Sandia Natl Labs, Scibased Mat Modeling Dept, Livermore, CA 94551 USA. USN, Res Lab, Multifunct Mat Branch, Washington, DC 20375 USA. Stanford Univ, Dept Mech Engn, Div Mech & Computat, Stanford, CA 94305 USA. RP Klein, PA (reprint author), Sandia Natl Labs, Scibased Mat Modeling Dept, POB 0969, Livermore, CA 94551 USA. EM paklein@andia.gov RI Gao, Huajian/F-9360-2010 NR 96 TC 76 Z9 77 U1 3 U2 12 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 DEC PY 2001 VL 37 IS 1-3 BP 99 EP 166 DI 10.1016/S0167-8442(01)00091-X PG 68 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 509MR UT WOS:000173152000008 ER PT J AU Psakhie, SG Horie, Y Ostermeyer, GP Korostelev, SY Smolin, AY Shilko, EV Dmitriev, AI Blatnik, S Spegel, M Zavsek, S AF Psakhie, SG Horie, Y Ostermeyer, GP Korostelev, SY Smolin, AY Shilko, EV Dmitriev, AI Blatnik, S Spegel, M Zavsek, S TI Movable cellular automata method for simulating materials with mesostructure SO THEORETICAL AND APPLIED FRACTURE MECHANICS LA English DT Article; Proceedings Paper CT 3rd International Conference on Mesomechanics CY JUN 13-16, 2000 CL XIAN, PEOPLES R CHINA ID STATE DEFORMATION; INCLINED CHUTE; DYNAMICS; FEATURES; SPHERES; DESIGN; MODEL AB Mathematical formalism and applications of the movable cellular automata (MCA) method are presented for solving problems of physical mesomechanics. Since the MCA is a discrete approach, it has advantages over that of the finite element method (FEM). Simulation results agree closely with the experimental data. The MCA approach cab solves mechanical engineering problems ranging from those in material science to those in structures and constructions. Computer simulation using MCA can also provide useful information in situations where direct measurements are not possible. (C) 2001 Published by Elsevier Science Ltd. C1 Russian Acad Sci, Inst Strenght Phys & Mat Sci, Tomsk 634021, Russia. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Tech Univ Carolo Wilhelmina Braunschweig, Inst Engn Mech, D-38106 Braunschweig, Germany. Jozef Stefan Inst, SI-1000 Ljubljana, Slovenia. IPAK, SI-3320 Velenje, Slovenia. Velenje Coal Mine, SI-3320 Velenje, Slovenia. RP Psakhie, SG (reprint author), Russian Acad Sci, Inst Strenght Phys & Mat Sci, Acad 2-1, Tomsk 634021, Russia. RI Psakhie, Sergey/F-1469-2014; Dmitriev, Andrey/D-6611-2014; Smolin, Alexey/L-6990-2013 OI Smolin, Alexey/0000-0003-0213-1701 NR 48 TC 74 Z9 98 U1 2 U2 16 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8442 J9 THEOR APPL FRACT MEC JI Theor. Appl. Fract. Mech. PD DEC PY 2001 VL 37 IS 1-3 BP 311 EP 334 DI 10.1016/S0167-8442(01)00079-9 PG 24 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 509MR UT WOS:000173152000014 ER PT J AU de Jong, WA Harrison, RJ Nichols, JA Dixon, DA AF de Jong, WA Harrison, RJ Nichols, JA Dixon, DA TI Fully relativistic correlated benchmark results for uranyl and a critical look at relativistic effective core potentials for uranium SO THEORETICAL CHEMISTRY ACCOUNTS LA English DT Article DE relativistic; uranyl; benchmark; CCSD(T); RECP ID SPIN-ORBIT OPERATORS; BASIS-SETS; HARTREE-FOCK; UO22+; NEON; MOLECULES; ACTINIDES; BORON; ION; UF6 AB A complete set of fully-relativistic benchmark results for the bond lengths and vibrational frequencies of uranyl at various levels of correlation treatment are presented. It is shown that the relativistic and correlation effects are of the same magnitude and should be treated on an equal footing. Results of uranyl calculations using various relativistic effective core potentials (RECP) are presented, Appropriate choices for RECPs for use in density functional theory (DFT) calculations in the local density approximation (LDA) and with the gradient-corrected B3LYP exchange-correlation functional are discussed. The conclusion is reached that small-core RECPs need to be used and that the best results as compared to the benchmark values are obtained by using a DFT functional that includes some fraction of Hartree-Fock Exchange. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP de Jong, WA (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. EM Wibe.DeJong@pnl.gov RI DE JONG, WIBE/A-5443-2008; OI DE JONG, WIBE/0000-0002-7114-8315; Nichols, Jeffrey/0000-0001-5454-9726 NR 28 TC 63 Z9 63 U1 0 U2 9 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1432-881X J9 THEOR CHEM ACC JI Theor. Chem. Acc. PD DEC PY 2001 VL 107 IS 1 BP 22 EP 26 DI 10.1007/s002140100293 PG 5 WC Chemistry, Physical SC Chemistry GA 510HY UT WOS:000173203700004 ER PT J AU Kim, MS Sabri, MI Miller, VH Kayton, RJ Dixon, DA Spencer, PS AF Kim, MS Sabri, MI Miller, VH Kayton, RJ Dixon, DA Spencer, PS TI 1,2-Diacetylbenzene, the neurotoxic metabolite of a chromogenic aromatic solvent, induces proximal axonopathy SO TOXICOLOGY AND APPLIED PHARMACOLOGY LA English DT Article DE diethylbenzene; diacetylbenzene; aromatic solvent; ninhydrin; tetralin; chromophore; neuropathy; axonopathy; green urine ID INDUCED SENSORIMOTOR NEUROPATHY; AUDITORY EVOKED-POTENTIALS; NORMAL-HEXANE; NEUROFILAMENT TRANSPORT; PYRROLE FORMATION; BUTYL KETONE; GUINEA-PIG; RATS; DIETHYLBENZENE; 1,2-DIETHYLBENZENE AB Several widely used aromatic hydrocarbon solvents reportedly induce blue-green discoloration of tissues and urine in animals and humans. The chomophore has been proposed to result from a ninhydrin-like reaction with amino groups in proteins. The present study examines the neurotoxic property of 1,2-diacetylbenzene (1,2-DAB), the active metabolite of the chromogenic and neurotoxic aromatic solvent 1,2-diethylbenzene. Rats treated with 1,2-DAB, but not with the nonchromogenic isomer 1,3-DAB or with ninhydrin developed blue discoloration of internal organs, including the brain and spinal cord. Only 1,2-DAB induced limb weakness associated with nerve fiber changes, which were most prominent in spinal cord and spinal roots. Changes began with the formation of proximal, neurofilament-filled axonal swellings of the type seen after treatment with 3,4-dimethyl-2,5-hexanedione, a potent derivative of the active metabolite of the neurotoxic aliphatic hydrocarbon solvents n-hexane and methyl n-butyl ketone. These compounds are metabolized to a T-diketone that forms pyrroles with target proteins, such as neurofilament proteins. A comparable mechanism is considered for 1,2-DAB, an aromatic T-diketone. (C) 2001 Elsevier Science. C1 Oregon Hlth & Sci Univ, Sch Med, Ctr Res Occupat & Environm Toxicol, Portland, OR 97201 USA. Oregon Hlth & Sci Univ, Sch Med, Dept Neurol, Portland, OR 97201 USA. Ctr Res Informat, Silver Spring, MD 20910 USA. Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Kim, MS (reprint author), Oregon Hlth & Sci Univ, Sch Med, Ctr Res Occupat & Environm Toxicol, Portland, OR 97201 USA. FU NIEHS NIH HHS [ES11384, 1P42 ES10338] NR 68 TC 20 Z9 21 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0041-008X J9 TOXICOL APPL PHARM JI Toxicol. Appl. Pharmacol. PD DEC 1 PY 2001 VL 177 IS 2 BP 121 EP 131 DI 10.1006/taap.2001.9301 PG 11 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA 506BR UT WOS:000172950500005 PM 11740911 ER PT J AU Wu, YS AF Wu, YS TI Non-Darcy displacement of immiscible fluids in porous media SO WATER RESOURCES RESEARCH LA English DT Article ID FLOW AB This paper presents a Buckley-Leverett analytical solution for non-Darcy displacement of two immiscible fluids in porous media. The multiphase non-Darcy displacement is described using a Forchheimer equation or other non-Darcy flow correlations under multiphase flow conditions. The analytical solution is used to obtain some insight into the physics of displacement involving non-Darcy flow effects in porous media. The solution reveals how non-Darcy displacement is controlled not only by relative permeability curves but also by non-Darcy flow coefficients as well as injection or flow rates. This analytical solution is then applied to verify a numerical simulator for modeling multiphase non-Darcy flow. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Wu, YS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, MS 90-1116,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Wu, Yu-Shu/A-5800-2011 NR 39 TC 13 Z9 18 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC PY 2001 VL 37 IS 12 BP 2943 EP 2950 DI 10.1029/2001WR000389 PG 8 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 511UB UT WOS:000173283000008 ER PT J AU Vesselinov, VV Neuman, SP Illman, WA AF Vesselinov, VV Neuman, SP Illman, WA TI Three-dimensional numerical inversion of pneumatic cross-hole tests in unsaturated fractured tuff 1. Methodology and borehole effects SO WATER RESOURCES RESEARCH LA English DT Article ID HYDRAULIC CONDUCTIVITY TENSOR; STEADY-STATE CONDITIONS; STATISTICAL APPROACH; AQUIFER HYDROLOGY; FIELD DETERMINATION; ANISOTROPIC MEDIA; INJECTION TESTS; PARAMETERS; TOMOGRAPHY; TRANSIENT AB We describe a three-dimensional numerical inverse model for the interpretation of cross-hole pneumatic tests in unsaturated fractured tuffs at the Apache Leap Research Site (ALRS) near Superior, Arizona. The model combines a finite volume flow simulator, FEHM, an automatic mesh generator, X3D, a parallelized version of an automatic parameter estimator, PEST, and a geostatistical package, GSTAT. The tests are simulated by considering single-phase airflow through a porous continuum, which represents primarily interconnected fractures at the site. The simulator solves the airflow equations in their original nonlinear form and accounts directly for the ability of all packed-off borehole intervals to store and conduct air through the system. Computations are performed in parallel on a supercomputer using 32 processors. We analyze pneumatic cross-hole test data, previously conducted by our group at ALRS, in two ways: (1) by considering pressure records from individual borehole monitoring intervals one at a time, while treating the rock as being spatially uniform, and (2) by considering pressure records from multiple tests and borehole monitoring intervals simultaneously, while treating the rock as being randomly heterogeneous. The first approach yields a series of equivalent air permeabilities and air-filled porosities for the rock volume being, tested, having length scales of the order of meters to tens of meters. The second approach yields a high-resolution geostatistical estimate of how air permeability and air-filled porosity, defined on grid blocks having a length scale of I m, vary spatially throughout the tested rock volume. It amounts to three-dimensional pneumatic "tomography" or stochastic imaging of the rock, a concept originally proposed by one of us in 1987. The first paper of this two-part series describes the field data, the model, and the effect of boreholes on pressure propagation through the rock. The second paper implements our approach on selected cross-hole test data from ALRS. C1 Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA. RP Vesselinov, VV (reprint author), Los Alamos Natl Lab, Hydrol Geochem & Geol Grp, EES-6,MS T003, Los Alamos, NM 87545 USA. RI Vesselinov, Velimir/P-4724-2016 OI Vesselinov, Velimir/0000-0002-6222-0530 NR 59 TC 67 Z9 67 U1 0 U2 5 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC PY 2001 VL 37 IS 12 BP 3001 EP 3017 DI 10.1029/2000WR000133 PG 17 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 511UB UT WOS:000173283000013 ER PT J AU Vesselinov, VV Neuman, SP Illman, WA AF Vesselinov, VV Neuman, SP Illman, WA TI Three-dimensional numerical inversion of pneumatic cross-hole tests in unsaturated fractured tuff 2. Equivalent parameters, high-resolution stochastic imaging and scale effects SO WATER RESOURCES RESEARCH LA English DT Article AB In paper I of this two-part series we described a three-dimensional numerical inverse model for the interpretation of cross-hole pneumatic tests in unsaturated fractured tuffs at the Apache Leap Research Site (ALRS) near Superior, Arizona. Our model is designed to analyze these data in two ways: (1) by considering pressure records from individual borehole monitoring intervals one at a time, while treating the rock as being spatially uniform, and (2) by considering pressure records from multiple tests and borehole monitoring intervals simultaneously, while treating the rock as being randomly heterogeneous. The first approach yields a series of equivalent air permeabilities and air-filled porosities for rock volumes having length scales ranging from meters to tens of meters, represented nominally by radius vectors extending from injection to monitoring intervals. The second approach yields a high-resolution geostatistical estimate of how air permeability and air-filled porosity, defined on grid blocks having a length scale of I in, vary spatially throughout the tested rock volume. It amounts to three-dimensional pneumatic "tomography" or stochastic imaging of the rock. Paper I described the field data, the model, and the effect of boreholes on pressure propagation through the rock. This second paper implements our inverse model on pressure data from five cross-hole tests at ALRS. We compare our cross-hole test interpretations by means of the two approaches with earlier interpretations by means of type curves and with geostatistical interpretations of single-hole test data. The comparisons show internal consistency between all pneumatic test interpretations and reveal a very pronounced scale effect in permeability and porosity at ALRS. C1 Univ Arizona, Dept Hydrol & Water Resources, Tucson, AZ 85721 USA. RP Vesselinov, VV (reprint author), Los Alamos Natl Lab, Hydrobiol Geochem & Geol Grp, EES-6,MS T003, Los Alamos, NM 87545 USA. RI Vesselinov, Velimir/P-4724-2016 OI Vesselinov, Velimir/0000-0002-6222-0530 NR 18 TC 93 Z9 93 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC PY 2001 VL 37 IS 12 BP 3019 EP 3041 DI 10.1029/2000WR000135 PG 23 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 511UB UT WOS:000173283000014 ER PT J AU Salve, R Oldenburg, CM AF Salve, R Oldenburg, CM TI Water flow within a fault in altered nonwelded tuff SO WATER RESOURCES RESEARCH LA English DT Article ID YUCCA-MOUNTAIN; PERMEABILITY; ROCKS; CRYSTALLINE AB In situ flow experiments were conducted at Alcove 4 in the Exploratory Studies Facility at Yucca Mountain to investigate flow dynamics in a small normal fault located in zeolitically and argillically altered tuffs of the nonwelded rocks of the Paintbrush group. Water was released at constant head into a packed-off interval straddling the fault within a horizontal borehole. Changes in water-intake rate into the interval were monitored along with saturation in the formation using boreholes installed with electrical resistivity probes. For water released into the fault the water-intake rate gradually fell from similar to200 to 50 mL min(-1) over a period of 41 hours of cumulative release time spread over 17 days of testing. Resistance changes recorded by electrical resistivity probes in matrix rock on either side of the fault interval suggest that flow in the fault spread out laterally in the fault plane. The time for the wetting front to travel 1 in in the fault was initially similar to0.15 days, Subsequent tests in the fault showed the response time to be dependent on wetting history, with a faster response observed in a wetter system. Data analysis using the numerical code TOUGH2/ITOUGH2 reveals that a simple decline in permeability caused by simulated clay swelling can explain the experimental observations. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Salve, R (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RI Oldenburg, Curtis/L-6219-2013 OI Oldenburg, Curtis/0000-0002-0132-6016 NR 27 TC 15 Z9 15 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC PY 2001 VL 37 IS 12 BP 3043 EP 3056 DI 10.1029/2001WR000322 PG 14 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 511UB UT WOS:000173283000015 ER PT J AU Zhou, QL Bensabat, J Bear, J AF Zhou, QL Bensabat, J Bear, J TI Accurate calculation of specific discharge in heterogeneous porous media SO WATER RESOURCES RESEARCH LA English DT Article ID VELOCITY AB porous media result in inaccuracy in simulating the local specific discharge field at and in the vicinity of an interface between subdomains of different material properties. The domain decomposition method used in multilayered systems and a consistent scheme in a randomly heterogeneous domain are applicable only to some particular cases, such as when the material interfaces are parallel to an axis. Along a material interface, the law of refraction of streamlines, related to both the tangential and the normal specific discharge components, should be satisfied. By incorporating these interface conditions into the weak formulation of Darcy's law, two consistent numerical schemes have been developed. These schemes can be applied to accurately and efficiently simulate the specific discharge field in a heterogeneous domain with different values of the ratio of hydraulic conductivities between adjacent elements. In particular, they provide an easy way for treating aquifers with semipervious layers as a single system. Numerical simulations have been used to demonstrate the capability and accuracy of the proposed schemes. Comparison between the specific discharge fields computed by the proposed schemes and by other techniques shows that the new schemes are superior to the traditional ones. C1 Technion Israel Inst Technol, Fac Civil Engn, IL-32000 Haifa, Israel. Environm & Water Resources Engn Inc, IL-31067 Haifa, Israel. RP Zhou, QL (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, 1 Cyclotron Rd,MS 90-1116, Berkeley, CA 94577 USA. RI Zhou, Quanlin/B-2455-2009 OI Zhou, Quanlin/0000-0001-6780-7536 NR 8 TC 12 Z9 14 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC PY 2001 VL 37 IS 12 BP 3057 EP 3069 DI 10.1029/1998WR900105 PG 13 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 511UB UT WOS:000173283000016 ER PT J AU Vasco, DW Karasaki, K Kishida, K AF Vasco, DW Karasaki, K Kishida, K TI A coupled inversion of pressure and surface displacement SO WATER RESOURCES RESEARCH LA English DT Article ID LONG VALLEY CALDERA; SOIL CONSOLIDATION; SAR INTERFEROMETRY; FLUID WITHDRAWAL; POROUS-MEDIA; WATER LEVEL; EARTH TIDES; CALIFORNIA; SUBSIDENCE; FLOW AB A coupled inversion of transient pressure observations and surface displacement measurements provides an efficient technique for estimating subsurface permeability variations. The methodology has the advantage of utilizing surface observations, which are typically much less expensive than measurements requiring boreholes. Furthermore, unlike many other geophysical observables, the relationship between surface deformation and reservoir pore fluid volume changes is relatively well understood. Our treatment enables us to partition the estimation problem into a sequence of three linear subproblems. An application of the approach to a set of tilt and borehole pressure data from the Raymond field site in California illustrates its efficiency and utility. The observations are associated with a well test in which fluid is withdrawn from a shallow fracture zone. During the test, 13 tiltmeters recorded the movement of the ground surface. Simultaneously, nine transducers measured pressure changes in boreholes intersecting the fracture system. We are able to image a high permeability, north trending channel located within the fracture zone. The existence and orientation of this high-permeability feature is substantiated by a semiquantitative analysis of some 4000 transient pressure curves. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. Kyoto Univ, Dept Civil Engn, Geotech Engn Lab, Sakyo Ku, Kyoto 6068501, Japan. RP Vasco, DW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Bldg 90,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Vasco, Donald/I-3167-2016 OI Vasco, Donald/0000-0003-1210-8628 NR 65 TC 28 Z9 29 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC PY 2001 VL 37 IS 12 BP 3071 EP 3089 DI 10.1029/2001WR000391 PG 19 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 511UB UT WOS:000173283000017 ER PT J AU Detwiler, RL Rajaram, H Glass, RJ AF Detwiler, RL Rajaram, H Glass, RJ TI Nonaqueous-phase-liquid dissolution in variable-aperture fractures: Development of a depth-averaged computational model with comparison to a physical experiment SO WATER RESOURCES RESEARCH LA English DT Article ID SATURATED SUBSURFACE SYSTEMS; MASS-TRANSFER RATES; SINGLE FRACTURE; POROUS-MEDIA; SOLUTE TRANSPORT; ROCK FRACTURE; FLOW; VISUALIZATION; SIMULATION; SOLUBILIZATION AB Dissolution of nonaqueous-phase liquids (NAPLs) from variable-aperture fractures couples fluid flow, transport of the dissolved NAPL, interphase mass transfer, and the corresponding NAPL-water-interface movement. Each of these fundamental processes is controlled by fracture-aperture variability and entrapped-NAPL geometry. We develop a depth-averaged computational model of dissolution that incorporates the fundamental processes that control dissolution at spatial resolutions that include all scales of variability within the flow field. Thus this model does not require empirical descriptions of local mass transfer rates. Furthermore, the depth-averaged approach allows us to simulate dissolution at scales that are larger than the scale of the largest entrapped NAPL blobs. We compare simulation results with an experiment in which we dissolved residual entrapped trichloroethylene (TCE) from a 15.4 X 30.3 cm, analog, variable-aperture fracture. We measured both fracture aperture and the TCE distribution within the fracture at high spatial resolution using light transmission techniques. Digital images acquired over the duration of the experiment recorded the evolution of the TCE distribution within the fracture and are directly compared with the results of a computational simulation. The evolution with time of the distribution of the entrapped TCE and the total TCE saturation are both predicted well by the dissolution model. These results suggest that detailed parametric studies, employing the depth-averaged dissolution model, can be used to develop a comprehensive understanding of NAPL dissolution in terms of parameters characterizing aperture variability, phase structure, and hydrodynamic conditions. C1 Sandia Natl Labs, Flow Visualizat & Proc Lab, Albuquerque, NM 87123 USA. Univ Colorado, Dept Civil Environm & Architectural Engn, Boulder, CO 80309 USA. RP Detwiler, RL (reprint author), Lawrence Livermore Natl Lab, Div Geophys & Global Secur, POB 808,L-206, Livermore, CA 94551 USA. RI Detwiler, Russell/C-3228-2008 OI Detwiler, Russell/0000-0002-7693-9271 NR 37 TC 23 Z9 23 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC PY 2001 VL 37 IS 12 BP 3115 EP 3129 DI 10.1029/2000WR000161 PG 15 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 511UB UT WOS:000173283000020 ER PT J AU Gamerdinger, AP Kaplan, DI Wellman, DM Serne, RJ AF Gamerdinger, AP Kaplan, DI Wellman, DM Serne, RJ TI Two-region flow and rate-limited sorption of uranium (VI) during transport in an unsaturated silt loam SO WATER RESOURCES RESEARCH LA English DT Article ID HETEROGENEOUS POROUS-MEDIA; SOLUTE TRANSPORT; ADSORPTION; WATER; SOIL; EQUILIBRIUM; SEDIMENTS; MODEL AB Uranium (VI) sorption during unsaturated transport was evaluated using a centrifuge method; conventional saturated columns and batch incubation procedures were used to isolate flow effects on sorption processes. Uranium (VI) sorption was dependent on flow velocity, and modeling indicated that 60% of sorption was rate-limited. Breakthrough curves were described and independently predicted with a two-site model; the mass transfer coefficient for sorption was assumed to be linearly related to velocity. While two-region flow contributed to disparity in apparent K-d values (linear distribution coefficient) at different water contents, the effect was explained by increased velocity in the mobile flow domain and not a decrease in availability of sorption sites. Hydrodynamic parameters for two-region transport, determined for a nonsorptive tracer at faster velocity (16 cm h(-1)), were fixed and described U(VI) transport at slower velocity (2 cm h-1). The rate-limited parameter for mass transfer between mobile and immobile water domains was linearly related to the average pore water velocity. Effective retardation factors varied with moisture saturation and the apparent Kd value and ranged from 7 for faster velocity experiments in a saturated column to 44 at slow velocity and 40% moisture saturation. C1 Washington State Univ, Dept Chem, Richland, WA 99352 USA. Washington State Univ, Ctr Multiphase Environm Res, Richland, WA 99352 USA. Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. Washington State Univ, Dept Chem, Pullman, WA 99164 USA. Washington State Univ, Ctr Multiphase Environm Res, Pullman, WA 99164 USA. RP Gamerdinger, AP (reprint author), Washington State Univ, Dept Chem, 2710 Univ Dr, Richland, WA 99352 USA. NR 28 TC 11 Z9 15 U1 2 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC PY 2001 VL 37 IS 12 BP 3147 EP 3153 DI 10.1029/2001WR000244 PG 7 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 511UB UT WOS:000173283000022 ER PT J AU Gamerdinger, AP Kaplan, DI Wellman, DM Serne, RJ AF Gamerdinger, AP Kaplan, DI Wellman, DM Serne, RJ TI Two-region flow and decreased sorption of uranium (VI) during transport in Hanford groundwater and unsaturated sands SO WATER RESOURCES RESEARCH LA English DT Article ID SOLUTE TRANSPORT; WATER; EQUILIBRIUM; ADSORPTION; MOBILE; MEDIA AB Uranium, U(VI), sorption and transport in unsaturated coarse- and fine-textured sands were evaluated using a centrifuge method; batch incubation and saturated column experiments were conducted to isolate the effect of flow from that of water content. At higher water contents (greater than or equal to66% saturation), decreases in U(VI) sorption were due to rate limitations. These breakthrough curves (BTCs) were well characterized with a two-site model for sorption (linear distribution coefficient K-d and first-order kinetic term); BTC characteristics were not captured with an equilibrium sorption model. At lower water contents (<30% saturation), two-region flow (mobile-immobile water) was apparent and had a significant impact on U(VI) sorption and transport. Uranium BTCs were characterized with two-region mass transfer parameters that were determined in experiments with conservative tracers. Decreases in uranium sorption at 22% and 13% saturation were greater than could be explained by velocity or rate-limited effects. Conservative tracer experiments indicated that solutes were excluded from a fraction of the pore volume; however, the decrease in uranium sorption was greater than predicted from this fraction. The results suggest that a greater propensity to sorb uranium was associated with sediment particles in contact with the excluded immobile water domain. C1 Washington State Univ, Dept Chem, Richland, WA 99352 USA. Washington State Univ, Ctr Multiphase Environm Res, Richland, WA 99352 USA. Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. Washington State Univ, Dept Chem, Pullman, WA 99164 USA. Washington State Univ, Ctr Multiphase Environm Res, Pullman, WA 99164 USA. RP Gamerdinger, AP (reprint author), Washington State Univ, Dept Chem, 2710 Univ Dr, Richland, WA 99352 USA. NR 21 TC 17 Z9 19 U1 1 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD DEC PY 2001 VL 37 IS 12 BP 3155 EP 3162 DI 10.1029/2001WR000247 PG 8 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 511UB UT WOS:000173283000023 ER PT J AU Elmer, JW Teruya, AT AF Elmer, JW Teruya, AT TI An enhanced faraday cup for rapid determination of power density distribution in electron beams SO WELDING JOURNAL LA English DT Article DE Faraday cup; electron beam welding; computed tomography; diagnostics power density; Gaussian distribution; beam focus ID PENETRATION AB Enhancements have been made to a modified Faraday cup (MFC) diagnostic device for measuring the power density distribution of high-power electron beams used for welding. The modifications consist of additions to the hardware components of a previously developed MFC for more complete capture of the electrons, better electrical grounding, and the addition of a new method for orienting the measured beam profile with respect to the coordinates of the welding chamber. These modifications improve the quality of the acquired data and enable a more accurate computed tomographic (CT) reconstruction of power density distribution of the electron beam than has been possible in the past. Comparisons were made between previous and enhanced versions of the MFC. Results demonstrated improved electron capture and improved signal-to-noise ratio with the new design, allowing the acquired beam profile to be CT reconstructed without noise filtering. In addition, Gaussian distributed beams were used to simulate beam profiles acquired by the MFC diagnostic as a, function of the finite width of the slits used to measure beam properties. From these simulations, the amount of error in the beam profile introduced by the slits was determined and a method for compensating for this error proposed. C1 Lawrence Livermore Natl Lab, Livermore, CA USA. RP Elmer, JW (reprint author), Lawrence Livermore Natl Lab, Livermore, CA USA. NR 12 TC 9 Z9 9 U1 0 U2 2 PU AMER WELDING SOC PI MIAMI PA 550 N W LEJEUNE RD, MIAMI, FL 33126 USA SN 0043-2296 J9 WELD J JI Weld. J. PD DEC PY 2001 VL 80 IS 12 BP 288S EP 295S PG 8 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 746LH UT WOS:000186747500016 ER PT J AU Kennamer, RA AF Kennamer, RA TI Relating climatological patterns to wetland conditions and wood duck production in the Southeastern Atlantic Coastal Plain SO WILDLIFE SOCIETY BULLETIN LA English DT Article DE Aix sponsa; Carolina bay; climate; hydrologic condition; South Carolina; Southeastern Atlantic Coastal Plain; wetland; wood duck ID REPRODUCTIVE-PERFORMANCE; WATERFOWL POPULATIONS; 2ND BROODS; AGE; RECRUITMENT; PHILOPATRY; DYNAMICS AB Efforts to index annual population size and recruitment of the wood duck (Aix sponsa) on a geographic scale sufficiently large to be useful in managing this species have met with mixed results. A general relationship between climatic factors and wood duck production has been the most economical and promising approach, particularly in the Southeast, though further refinement or understanding of factors mediating the relationship has been lacking. Development of climate-based models that predict wetland hydrologic conditions during the wood duck breeding season can be a useful step to index recruitment and may provide useful insights into population dynamics. In this study, I illustrate the concept's potential by developing a robust deterministic model of wetland water conditions on the 78,000-ha Savannah River Site (SRS) in west-central South Carolina over a 13-year period (1984-1996). During 6 years (1982-1987) when more than 90% of all hatched ducklings were marked before leaving nest boxes on the SRS, production of female ducklings was related positively to estimated female recruitment into the population the following year (combined breeding and nonbreeding yearling population segments; r(S)=0.90, P=0.015), indicating that duckling production was a reasonable proxy for recruitment. The return of females initially marked as ducklings suggested that deferred yearling breeding was highest in dry years that were preceded by wetter years, thereby contributing to lower productivity in such years. Annual wetland condition indices were related to 15 years of duckling production from SRS nest boxes. Productivity of wood ducks was positively associated with wetland hydrologic conditions. In wet years, an average of 9.8 +/- 0.7 (SE) ducklings was produced by each female in the breeding population, but only 8.6 +/- 0.5 (SE) ducklings/female were produced in dry years. Greater productivity in wet years was attributed in part to longer breeding seasons, which allowed more females in the population to produce second broods, and to reduced predation rates. Additional insights gained through application of the method are discussed. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Kennamer, RA (reprint author), Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. NR 55 TC 5 Z9 6 U1 1 U2 11 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 USA SN 0091-7648 J9 WILDLIFE SOC B JI Wildl. Soc. Bull. PD WIN PY 2001 VL 29 IS 4 BP 1193 EP 1205 PG 13 WC Biodiversity Conservation SC Biodiversity & Conservation GA 507EW UT WOS:000173014900025 ER PT J AU Faybishenko, B Babchin, AJ Frenkel, AL Halpern, D Sivashinsky, GI AF Faybishenko, B Babchin, AJ Frenkel, AL Halpern, D Sivashinsky, GI TI A model of chaotic evolution of an ultrathin liquid film flowing down an inclined plane SO COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS LA English DT Article ID IRREGULAR WAVY FLOW; INSTABILITY; SATURATION; EQUATION AB Chemical and colloidal transport processes in partially saturated porous and fractured media are dependent on liquid flow along a solid surface, which may be chaotic even for small Reynolds numbers. This paper presents the derivation of a one-dimensional evolution equation describing the slow motion (small Reynolds numbers, R < < 1) of a very thin liquid film flowing down an inclined impermeable plane. In this equation, gravitational, capillary, and molecular forces are taken into account. The addition of the molecular force term leads to a highly nonlinear equation governing the spatial and temporal evolution of film thickness. In a weakly nonlinear limit, this evolution equation is rescaled to a canonical form. The latter predicts a chaotic hydrodynamic instability for the film surface. This chaotic behavior is illustrated using the 3D projections of pseudo-phase space attractors for the spatial and temporal variations of the dimensionless film thickness. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Tel Aviv Univ, Dept Math Sci, IL-69978 Ramat Aviv, Israel. Univ Alabama, Dept Math, Tuscaloosa, AL 35487 USA. Alberta Res Council, Edmonton, AB T6N 1E4, Canada. RP Faybishenko, B (reprint author), Lawrence Berkeley Lab, MS 90-1116, Berkeley, CA 94720 USA. RI Halpern, David/H-7323-2012; Frenkel, Alexander /C-5276-2013; Halpern, David/F-5041-2014; Faybishenko, Boris/G-3363-2015 OI Halpern, David/0000-0003-2255-156X; Faybishenko, Boris/0000-0003-0085-8499 NR 23 TC 4 Z9 4 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-7757 J9 COLLOID SURFACE A JI Colloid Surf. A-Physicochem. Eng. Asp. PD NOV 30 PY 2001 VL 192 IS 1-3 BP 377 EP 385 DI 10.1016/S0927-7757(01)00738-5 PG 9 WC Chemistry, Physical SC Chemistry GA 474JM UT WOS:000171103400028 ER PT J AU Goldstein, SJ Lea, DW Chakraborty, S Kashgarian, M Murrell, MT AF Goldstein, SJ Lea, DW Chakraborty, S Kashgarian, M Murrell, MT TI Uranium-series and radiocarbon geochronology of deep-sea corals: implications for Southern Ocean ventilation rates and the oceanic carbon cycle SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE Antarctic Ocean; uranium disequilibrium; Anthozoa; deep-sea environment; carbon cycle; radioactive isotopes ID IONIZATION MASS-SPECTROMETRY; THORIUM ISOTOPES; ATMOSPHERIC CO2; AGE CALIBRATION; NORTH-ATLANTIC; CLIMATE-CHANGE; WATER; CIRCULATION; C-14; TH AB We present new uranium-series and radiocarbon measurements for deep-sea corals from the Southern Ocean. These data are used to reconstruct ventilation ages, both at present and at the end of the last glacial period approximately 16500 years ago. We apply an improved two-component mixing approach to correct uranium-series dates for contaminant thorium and protactinium present in oxide coatings. Calculated seawater radiocarbon values for contemporary samples decrease with depth in the water column and agree with direct seawater radiocarbon measurements for this area. This indicates that deep-sea corals can accurately record seawater radiocarbon distributions. Two of three glacial samples experienced open-system uranium-series systematics, however, a third sample from the Drake Passage yields concordant thorium and protactinium dates as well as seawater values for initial U-234/U-238. This coral yields a ventilation age that is approximately 20-40% greater than modern values for its location. This increase is consistent with published deep-sea coral and calibrated planktonic-benthic foraminifera radiocarbon data. suggesting that the glacial oceans as a whole may have been substantially less ventilated, presumably due to decreased formation of North Atlantic Deep Water. An overall decrease in oceanic mixing rates could have contributed to lower dissolved carbon in surface ocean water and lower atmospheric pCO(2) during the past glacial period. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. Univ Calif Santa Barbara, Dept Geol Sci, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Inst Marine Sci, Santa Barbara, CA 93106 USA. Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. RP Los Alamos Natl Lab, Div Chem, MS K484, Los Alamos, NM 87545 USA. EM sgoldstein@lanl.gov RI Kashgarian, Michaele/E-1665-2011 OI Kashgarian, Michaele/0000-0001-7824-8418 NR 48 TC 62 Z9 63 U1 0 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X EI 1385-013X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD NOV 30 PY 2001 VL 193 IS 1-2 BP 167 EP 182 DI 10.1016/S0012-821X(01)00494-0 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 499MU UT WOS:000172575600015 ER PT J AU Hawkins, SM Kohwi-Shigematsu, T Skalnik, DG AF Hawkins, SM Kohwi-Shigematsu, T Skalnik, DG TI The matrix attachment region-binding protein SATB1 interacts with multiple elements within the gp91(phox) promoter and is down-regulated during myeloid differentiation SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID CCAAT DISPLACEMENT PROTEIN; CHRONIC GRANULOMATOUS-DISEASE; LEUKEMIA-CELL-LINE; CHROMOSOMAL LOOP ANCHORAGE; CUT HOMEODOMAIN PROTEINS; NUCLEAR MATRIX; DNA-BINDING; GENE-EXPRESSION; GP91-PHOX PROMOTER; CIS-ELEMENTS AB The gp91(phox) gene encodes a component of the respiratory burst NADPH oxidase complex and is highly expressed in mature myeloid cells. The transcriptional repressor CCAAT displacement protein binds to at least five sites within the proximal gp91(phox) promoter and represses expression prior to terminal phagocyte differentiation. The DNA binding activity of CCAAT displacement protein decreases during terminal phagocyte differentiation, thus permitting the binding of transcriptional activators and induction of gp91(phox) expression. We report here that the matrix attachment region-binding protein SATB1 interacts with at least seven sites within the -1542 to +12-base pair gp91(phox) promoter. Four additional binding sites for CCAAT displacement protein were also identified. Furthermore, the most proximal SATB1-binding site within the gp91(phox) promoter binds specifically to the nuclear matrix fraction in vitro. SATB1 expression is downregulated during terminal myeloid cell differentiation, coincident with induction of gp91(phox) expression. Transient transfection assays demonstrate that a SATB1-binding site derived from the gp91(phox) promoter represses promoter activity in cells expressing SATB1. These findings underscore the importance of transcriptional repression in the regulation of gp91(phox) expression and reveal a candidate myeloid cell target gene for SATB1, a factor previously found to be essential for T cell development. C1 Indiana Univ, Sch Med, Herman B Wells Ctr Pediat Res, Sect Pediat Hematol Oncol, Indianapolis, IN 46202 USA. Indiana Univ, Sch Med, Dept Pediat, Indianapolis, IN 46202 USA. Indiana Univ, Sch Med, Dept Biochem & Mol Biol, Indianapolis, IN 46202 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Skalnik, DG (reprint author), Indiana Univ, Sch Med, Herman B Wells Ctr Pediat Res, Sect Pediat Hematol Oncol, Canc Res Bldg,1044 W Walnut St,Rm 472, Indianapolis, IN 46202 USA. RI Hawkins, Shannon/B-7095-2015 OI Hawkins, Shannon/0000-0002-0727-3971 FU NCI NIH HHS [R01 CA58947, R01 CA39681] NR 70 TC 18 Z9 19 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 NOV 30 PY 2001 VL 276 IS 48 BP 44472 EP 44480 DI 10.1074/jbc.M104193200 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 496QD UT WOS:000172406700018 PM 11577075 ER PT J AU Streets, DG Jiang, KJ Hu, XL Sinton, JE Zhang, XQ Xu, DY Jacobson, MZ Hansen, JE AF Streets, DG Jiang, KJ Hu, XL Sinton, JE Zhang, XQ Xu, DY Jacobson, MZ Hansen, JE TI Climate change - Recent reductions in China's greenhouse gas emissions SO SCIENCE LA English DT Editorial Material C1 Argonne Natl Lab, Decis & Informat Sci Div, Argonne, IL 60439 USA. Energy Res Inst, Ctr Energy Environm & Climate Change, Beijing 100038, Peoples R China. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Energy Anal, Berkeley, CA 94720 USA. Chinese Acad Forestry, Forest Ecol & Environm Inst, Beijing 100091, Peoples R China. Stanford Univ, Dept Civil & Environm Engn, Stanford, CA 94305 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. RP Streets, DG (reprint author), Argonne Natl Lab, Decis & Informat Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 19 TC 94 Z9 123 U1 6 U2 40 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 NOV 30 PY 2001 VL 294 IS 5548 BP 1835 EP + DI 10.1126/science.1065226 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 497PQ UT WOS:000172465000028 PM 11729288 ER PT J AU Baur, K Brennan, S Burrow, B Werho, D Pianetta, P AF Baur, K Brennan, S Burrow, B Werho, D Pianetta, P TI Laboratory and synchrotron radiation total-reflection X-ray fluorescence: new perspectives in detection limits and data analysis SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Article; Proceedings Paper CT 8th Conference on Total Reflection X-Ray Fluorescence Analysis and Related Methods CY SEP 25-29, 2000 CL VIENNA, AUSTRIA DE total reflection X-ray fluorescence; low Z elements; Stanford Synchrotron Radiation Laboratory ID RAMAN-SCATTERING; SPECTROSCOPY; SILICON AB Having established detection limits for transition elements exceeding current requirements of the semiconductor industry, our recent efforts at the Stanford Synchrotron Radiation Laboratory (SSRL) have focused on the improvement of the detection sensitivity for light elements such as Al. Data analysis is particularly challenging for Al, due to the presence of the neighboring Si signal from the substrate. Detection limits can be significantly improved by tuning the excitation energy below the Si-K absorption edge. For conventional TXRF systems this can be done by using a W-M alpha fluorescence line (1.78 keV) for excitation. At a synchrotron radiation facility energy tunability is available. However, in both cases this results in a substantial increase in background due to resonant X-ray Raman scattering. This scattering dominates the background under the Al K alpha fluorescence line, and consequently limits the achievable sensitivity for the detection of Al surface contaminants. In particular, we find that for a precise determination of the achievable sensitivity, the specific shape of the continuous Raman background must be taken into account in the data analysis. The data deconvolution presented here opens a new perspective for conventional TXRF systems to mitigate this background limitation. This results in a minimum detection limit of 2.4 X 10(9) atoms/cm(2) for Al. Based on these results it will also be demonstrated that by improving the detector resolution, the minimum detection limit can be improved significantly. For a detector resolution of 15 eV as predicted for novel superconducting tunnel junction detectors, an improvement in minimum detection limit of approximately a factor of 3 can be estimated. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. ACCUREL, Sunnyvale, CA USA. Motorola Inc, Mesa, AZ 85202 USA. RP Baur, K (reprint author), Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NR 18 TC 15 Z9 15 U1 0 U2 2 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 NOV 30 PY 2001 VL 56 IS 11 SI SI BP 2049 EP 2056 DI 10.1016/S0584-8547(01)00324-X PG 8 WC Spectroscopy SC Spectroscopy GA 501XK UT WOS:000172711200007 ER PT J AU Streli, C Wobrauschek, P Kregsamer, P Pepponi, G Pianetta, P Pahlke, S Fabry, L AF Streli, C Wobrauschek, P Kregsamer, P Pepponi, G Pianetta, P Pahlke, S Fabry, L TI Synchrotron radiation induced total reflection X-ray fluorescence of low Z elements on Si wafer surfaces at SSRL - comparison of excitation geometries and conditions SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Article; Proceedings Paper CT 8th Conference on Total Reflection X-Ray Fluorescence Analysis and Related Methods CY SEP 25-29, 2000 CL VIENNA, AUSTRIA DE low Z elements; ultra trace levels; Si wafer surfaces; SR-TXRF; synchrotron radiation ID LIGHT-ELEMENTS; TRACE ANALYSIS; SPECTROSCOPY; SILICON AB The analysis of low Z elements, like Na and Al at ultra trace levels ( < 10(10) atoms/cm(2)) on Si wafer surfaces is required by the semiconductor industry. Synchrotron radiation induced total reflection X-ray fluorescence analysis (SR-TXRF) is a promising method to fulfill this task, if a special energy dispersive detector with an ultra thin window is used. Synchrotron radiation is the ideal excitation source for TXRF of low Z elements due to its intense, naturally collimated and linearly polarized radiation with a wide spectral range down to low energies even below 1 keV. TXRF offers some advantages for wafer surface analysis such as non-destructive analysis and mapping capabilities. Experiments have been performed at the Stanford Synchrotron Radiation Lab (SSRL) using Beamline 3-4 (BL 3-4), a bending magnet beamline using white (< 3 keV) and monochromatic radiation, as well as Beamline 3-3 (BL 3-3), using a crystal monochromator as well as a multilayer monochromator. A comparison of excitation-detection geometry was performed, using a side-looking detector with a vertically positioned wafer as well as a down-looking detector with a horizontally arranged wafer. The advantages and disadvantages of the various geometrical and excitation conditions are presented and the results compared. Detection limits are in the 100-fg range for Na, as determined with droplet samples on Si wafer surfaces. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Vienna, Atominst Osterrich, A-1020 Vienna, Austria. SSRL, Stanford, CA USA. Wacker Siltron AG, Burghausen, Germany. RP Streli, C (reprint author), Univ Vienna, Atominst Osterrich, A-1020 Vienna, Austria. OI Streli, Christina/0000-0002-5141-3177; Pepponi, Giancarlo/0000-0002-7397-1946 NR 20 TC 12 Z9 12 U1 0 U2 1 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 NOV 30 PY 2001 VL 56 IS 11 SI SI BP 2085 EP 2094 DI 10.1016/S0584-8547(01)00322-6 PG 10 WC Spectroscopy SC Spectroscopy GA 501XK UT WOS:000172711200011 ER PT J AU Sasaki, T Koshizaki, N Yoon, JW Beck, KM AF Sasaki, T Koshizaki, N Yoon, JW Beck, KM TI Preparation of Pt/TiO2 nanocomposite thin films by pulsed laser deposition and their photoelectrochemical behaviors SO JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY LA English DT Article; Proceedings Paper CT International Symposium on Photoreaction Control and Photofunctional Materials (PCPM 2001) CY MAR 14-16, 2001 CL TSUKUBA, JAPAN DE pulsed laser deposition; thin film; nanocomposite electrode; photoelectrode ID TITANIUM-DIOXIDE; TIO2 FILMS; PHOTOLUMINESCENCE; SIO2 AB Pt/TiO2 nanocomposite films were prepared from the sintered mixture targets of Pt and TiO2 by pulsed laser deposition. Pt/Ti atomic ratios in the deposited films are more strongly dependent on the initial content of Pt in the target than on the laser fluence. It is inferred from transmission electron microscope, X-ray photoelectron spectroscopy and X-ray diffraction analyses that as-deposited Pt/TiO2 nanocomposite films are composed of metallic Pt nanoparticles with a diameter of about 30 nm and an amorphous TiO2 matrix, which are crystallized into the dominant crystal structure of the anatase phase after the heating at 600 degreesC. The optical bandgap of Pt/TiO2 nanocomposite films was less than that of the pure TiO2 film and photoluminescence emission was observed between 680 and 800 nm at 24 K. Some energy levels can be formed by the interface between Pt nanoparticles and TiO2, which also affect the photoelectrochemical properties of Pt/TiO2 nanocomposite electrodes. The anodic photocurrents at 1.0 V of Pt/TiO2 nanocomposite electrodes were observed in the visible light range. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Inst Adv Ind Sci & Technol, Nanoarchitecton Res Ctr, Tsukuba, Ibaraki 3058565, Japan. Pacific NW Natl Lab K8 88, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Natl Inst Adv Ind Sci & Technol, Nanoarchitecton Res Ctr, Cent 5,1-1-1 Higashi, Tsukuba, Ibaraki 3058565, Japan. EM takeshi.sasaki@aist.go.jp RI Koshizaki, Naoto/E-2024-2011 NR 22 TC 36 Z9 46 U1 1 U2 13 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 NOV 29 PY 2001 VL 145 IS 1-2 SI SI BP 11 EP 16 DI 10.1016/S1010-6030(01)00558-5 PG 6 WC Chemistry, Physical SC Chemistry GA 496HV UT WOS:000172390900003 ER PT J AU Pratt, LR LaViolette, RA Gomez, MA Gentile, ME AF Pratt, LR LaViolette, RA Gomez, MA Gentile, ME TI Quasi-chemical theory for the statistical thermodynamics of the hard-sphere fluid SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID HYDROPHOBIC INTERACTIONS; TRANSIENT CAVITIES; MOLECULAR LIQUIDS; FREE-VOLUME; SYSTEMS; MODELS; WATER; DEPENDENCE; CONSISTENT; HYDRATION AB We develop a quasi-chemical theory for the study of packing thermodynamics in dense liquids. The situation of hard-core interactions is addressed by considering the binding of solvent molecules to a precisely defined cavity in order to assess the probability that the cavity is entirely evacuated. The primitive quasi-chemical approximation corresponds to an extension of the Poisson distribution used as a default model in an information theory approach. This primitive quasi-chemical theory is in good qualitative agreement with the observations for the hard-sphere fluid of occupancy distributions that are central to quasi-chemical theories but begins to be quantitatively erroneous for the equation of state in the dense liquid regime of pd(3) > 0.6. How the quasichemical approach can be iterated to treat correlation effects is addressed. Consideration of neglected correlation effects leads to a simple model for the form of those contributions neglected by the primitive quasi-chemical approximation. These considerations, supported by simulation observations, identify a "break away" phenomena that requires special thermodynamic consideration for the zero (0) occupancy case as distinct from the rest of the distribution. An empirical treatment leads to a one-parameter model occupancy distribution that accurately fits the hard-sphere equation of state and observed distributions. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Idaho Natl Lab, Idaho Falls, ID 83415 USA. Vassar Coll, Dept Chem, Poughkeepsie, NY 12603 USA. RP Pratt, LR (reprint author), Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. RI Pratt, Lawrence/H-7955-2012 OI Pratt, Lawrence/0000-0003-2351-7451 NR 47 TC 34 Z9 34 U1 1 U2 11 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 NOV 29 PY 2001 VL 105 IS 47 BP 11662 EP 11668 DI 10.1021/jp011525w PG 7 WC Chemistry, Physical SC Chemistry GA 497HX UT WOS:000172450300019 ER PT J AU Kathmann, SM Hale, BN AF Kathmann, SM Hale, BN TI Monte Carlo simulations of small sulfuric acid-water clusters SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID BINARY NUCLEATION; HOMOGENEOUS NUCLEATION; TRANSIENT NUCLEATION; ANTARCTIC OZONE; VAPOR; MIXTURES; DEPLETION; KINETICS; SYSTEMS; PHASE AB Effective atom-atom potentials are developed for binary sulfuric acid-water clusters and applied in a Bennett Metropolis Monte Carlo calculation to determine free energy differences for small neighboring sized clusters of fixed composition at 298 K. The atom-atom pair potentials consist of Lennard-Jones short-range and Coulombic long-range terms and assume rigid SO42 delta- with two unconstrained Hdelta+ and rigid H2O molecules interacting via revised central force (RSL2) potentials. The potential parameters are determined from both ab initio studies and tests of the potential using the statistical mechanical formalism for binary cluster size distributions. In the potential tests, fixed composition free energy differences, deltaf(km,m), for [H2O](km)[H2SO4](m) clusters are plotted versus (km + m)(-1/3), and the resulting slope and intercept (in the large cluster regime) are used to extract model dependent binary liquid surface tension and partial vapor pressures at 298 K. The potential parameters are adjusted to obtain approximate agreement with experimental surface tension and partial vapor pressures for k = 1 and 4 (84% and 57% weight percent H2SO4, respectively). The free energy ;differences for m less than or equal to 15 are presented, together with internal cluster energy contributions, snapshots of cluster structure, and evidence for onset of the large cluster regime near m = 5. The long-range goals have been to test the free energy difference procedure for studying binary cluster properties and to develop model potentials appropriate for the simulation of small binary clusters at low temperatures characteristic of stratospheric sulfuric acid-water aerosols. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99353 USA. Univ Missouri, Dept Phys, Rolla, MO 65409 USA. RP Kathmann, SM (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99353 USA. NR 70 TC 27 Z9 27 U1 2 U2 8 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 NOV 29 PY 2001 VL 105 IS 47 BP 11719 EP 11728 DI 10.1021/jp0116499 PG 10 WC Chemistry, Physical SC Chemistry GA 497HX UT WOS:000172450300025 ER PT J AU McGraw, R AF McGraw, R TI Dynamics of barrier crossing in classical nucleation theory SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID GAS-LIQUID NUCLEATION; LENNARD-JONES SYSTEM; MOLECULAR THEORY; SULFURIC-ACID; MIXTURES; WATER; VAPOR; TEMPERATURE; MODEL AB The dynamics of nucleation barrier crossing is examined using Becker-Doring kinetics, matrix methods, and stochastic model simulation. Fundamental connections between resistance to crossing and fluctuations in cluster size are derived using the Kubo-Nyquist relations. For analysis of nucleation kinetics, the matrix approach of Shugard and Reiss is supplemented with a novel extension based on recursion/projection operator methods. The combined approach yields nested sequences of upper and lower bounds to the relaxation rates of clusters coupled to a thermal bath. Fluctuations are studied using simulations based on a stochastic model of cluster evaporation/growth. Under typical conditions, it is found that relaxation from the top of the barrier is slow, due to multiple re-crossings, and the transmission coefficient for nucleation is small and extremely difficult to estimate from single-cluster simulations using standard Bennett-Chandler and Krainers models. A new approach based on relaxation on a "dual" potential surface is introduced. It is shown that the dual model provides an optimal weighted cluster sampling and reliable estimation of the transmission coefficient (to within a few percent). Collectively, these methods address the efficient determination of nucleation rates from computer simulations of individual cluster evaporation/growth events. C1 Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. RP McGraw, R (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. NR 36 TC 11 Z9 11 U1 1 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 NOV 29 PY 2001 VL 105 IS 47 BP 11838 EP 11848 DI 10.1021/jp011914q PG 11 WC Chemistry, Physical SC Chemistry GA 497HX UT WOS:000172450300041 ER PT J AU Weinberg, AM AF Weinberg, AM TI Messenger RNA: origins of a discovery SO NATURE LA English DT Letter C1 Oak Ridge Associated Univ, Oak Ridge, TN 37831 USA. RP Weinberg, AM (reprint author), Oak Ridge Associated Univ, POB 117, Oak Ridge, TN 37831 USA. NR 4 TC 2 Z9 2 U1 1 U2 2 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD NOV 29 PY 2001 VL 414 IS 6863 BP 485 EP 485 DI 10.1038/35107234 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 496PV UT WOS:000172405900016 PM 11734821 ER PT J AU Deb, SK Wilding, M Somayazulu, M McMillan, PF AF Deb, SK Wilding, M Somayazulu, M McMillan, PF TI Pressure-induced amorphization and an amorphous-amorphous transition in densified porous silicon SO NATURE LA English DT Article ID PHASE-TRANSITION; TEMPERATURE; LIQUID; SI; GE; CRYSTALLIZATION; NANOCRYSTALS; RELAXATION; SURFACE; TIN AB Crystalline and amorphous forms of silicon are the principal materials used for solid-state electronics and photovoltaics technologies. Silicon is therefore a well-studied material, although new structures and properties are still being discovered(1-4). Compression of bulk silicon, which is tetrahedrally coordinated at atmospheric pressure, results in a transition to octahedrally coordinated metallic phases(5). In compressed nanocrystalline Si particles, the initial diamond structure persists to higher pressure than for bulk material, before transforming to high-density crystals(6). Here we report compression experiments on films of porous Si, which contains nanometre-sized domains of diamond-structured material(7-9). At pressures larger than 10 GPa we observed pressure-induced amorphization(10,11). Furthermore, we rnd from Raman spectroscopy measurements that the high-density amorphous form obtained by this process transforms to low-density amorphous silicon upon decompression. This amorphous-amorphous transition is remarkably similar to that reported previously for water(12,13), which suggests an underlying transition between a high-density and a low-density liquid phase in supercooled Si (refs 10, 14, 15). The Si melting temperature decreases with increasing pressure, and the crystalline semiconductor melts to a metallic liquid with average coordination similar to5 (ref. 16). C1 UCL, Christopher Ingold Labs, Dept Chem, London WC1H 0AJ, England. Royal Inst Great Britain, Davy Faraday Res Lab, London W1X 4BS, England. Argonne Natl Lab, Adv Photon Source, HPCAT, Argonne, IL 60439 USA. Univ Calif Davis, Thermochem Facil, Davis, CA 95616 USA. Bhabha Atom Res Ctr, Div Solid State Phys, Mumbai 400085, India. RP McMillan, PF (reprint author), UCL, Christopher Ingold Labs, Dept Chem, 20 Gordon St, London WC1H 0AJ, England. EM paulm@ri.ac.uk NR 30 TC 230 Z9 232 U1 4 U2 61 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD NOV 29 PY 2001 VL 414 IS 6863 BP 528 EP 530 DI 10.1038/35107036 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 496PV UT WOS:000172405900042 PM 11734849 ER PT J AU Molchanov, VV Alkhazov, G Atamantchouk, AG Balatz, MY Bondar, NF Casey, D Cooper, PS Dauwe, LJ Davidenko, GV Dersch, U Dolgolenko, AG Dzyubenko, GB Edelstein, R Emediato, L Endler, AMF Engelfried, J Eschrich, I Escobar, CO Evdokimov, AV Ferbel, T Filimonov, IS Garcia, F Gaspero, M Giller, I Golovtsov, VL Gouffon, P Gulmez, E Hammer, C Kangling, H Iori, M Jun, SY Kaya, M Kilmer, J Kim, VT Kochenda, LM Konorov, I Kozhevnikov, AP Krivshich, AG Kruger, H Kubantsev, MA Kubarovsky, VP Kulyavtsev, AI Kuropatkin, NP Kurshetsov, VF Kushnirenko, A Kwan, S Lach, J Lamberto, A Landsberg, LG Larin, I Leikin, EM Li, YS Luksys, M Lungov, T Maleev, VP Mao, D Mao, CS Mao, ZL Mathew, P Mattson, M Matveev, V McCliment, E Moinester, MA Morelos, A Mukhin, VA Nelson, KD Nemitkin, AV Neoustroev, PV Newsom, C Nilov, AP Nurushev, SB Ocherashvili, A Onel, Y Ozel, E Ozkorucuklu, S Penzo, A Petrenko, SV Pogodin, P Procario, M Prutskoi, VA Ramberg, E Rappazzo, GF Razmyslovich, BV Rud, VI Russ, J Schiavon, P Simon, J Sitnikov, AI Skow, D Slattery, P Smith, VJ Srivastava, M Steiner, V Stepanov, V Stutte, L Svoiski, M Terentyev, NK Thomas, GP Uvarov, LN Vasiliev, AN Vavilov, DV Verebryusov, VS Victorov, VA Vishnyakov, VE Vorobyov, AA Vorwalter, K You, J Zhao, WH Zheng, SC Zhu, ZH Zielinski, M Zukanovich-Funchal, R AF Molchanov, VV Alkhazov, G Atamantchouk, AG Balatz, MY Bondar, NF Casey, D Cooper, PS Dauwe, LJ Davidenko, GV Dersch, U Dolgolenko, AG Dzyubenko, GB Edelstein, R Emediato, L Endler, AMF Engelfried, J Eschrich, I Escobar, CO Evdokimov, AV Ferbel, T Filimonov, IS Garcia, F Gaspero, M Giller, I Golovtsov, VL Gouffon, P Gulmez, E Hammer, C Kangling, H Iori, M Jun, SY Kaya, M Kilmer, J Kim, VT Kochenda, LM Konorov, I Kozhevnikov, AP Krivshich, AG Kruger, H Kubantsev, MA Kubarovsky, VP Kulyavtsev, AI Kuropatkin, NP Kurshetsov, VF Kushnirenko, A Kwan, S Lach, J Lamberto, A Landsberg, LG Larin, I Leikin, EM Li, YS Luksys, M Lungov, T Maleev, VP Mao, D Mao, CS Mao, ZL Mathew, P Mattson, M Matveev, V McCliment, E Moinester, MA Morelos, A Mukhin, VA Nelson, KD Nemitkin, AV Neoustroev, PV Newsom, C Nilov, AP Nurushev, SB Ocherashvili, A Onel, Y Ozel, E Ozkorucuklu, S Penzo, A Petrenko, SV Pogodin, P Procario, M Prutskoi, VA Ramberg, E Rappazzo, GF Razmyslovich, BV Rud, VI Russ, J Schiavon, P Simon, J Sitnikov, AI Skow, D Slattery, P Smith, VJ Srivastava, M Steiner, V Stepanov, V Stutte, L Svoiski, M Terentyev, NK Thomas, GP Uvarov, LN Vasiliev, AN Vavilov, DV Verebryusov, VS Victorov, VA Vishnyakov, VE Vorobyov, AA Vorwalter, K You, J Zhao, WH Zheng, SC Zhu, ZH Zielinski, M Zukanovich-Funchal, R CA SELEX Collaboration TI Radiative decay width of the a(2)(1320)(-) meson SO PHYSICS LETTERS B LA English DT Article DE radiative decay; Primakoff effect; a(2) (1320) ID RESONANCE PRODUCTION; NUCLEI; GEV/C; WAVE AB Coherent pi (+)pi (-)pi (-) production in the interactions of a beam of 600GeV pi (-) mesons with C, Cu and Pb nuclei has been studied with the SELEX facility (Experiment E781 at Fermilab). The a(2)(1320) meson signal has been detected in the Coulomb (low q(2)) region. The Primakoff formalism used to extract radiative decay width of this meson yields Gamma = 284 +/- 25 +/- 25 keV, which is the most precise measurement to date. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Inst High Energy Phys, Protvino, Russia. Ball State Univ, Muncie, IN 47306 USA. Bogazici Univ, TR-80815 Bebek, Istanbul, Turkey. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Inst High Energy Phys, Beijing 100039, Peoples R China. Inst Theoret & Expt Phys, Moscow 117259, Russia. Max Planck Inst Kernphys, D-69117 Heidelberg, Germany. Moscow MV Lomonosov State Univ, Moscow, Russia. Petersburg Nucl Phys Inst, St Petersburg, Russia. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Univ Autonoma San Luis Potosi, San Luis Potosi, Mexico. Univ Fed Paraiba, BR-58059900 Joao Pessoa, Paraiba, Brazil. Univ Bristol, Bristol BS8 1TL, Avon, England. Univ Iowa, Iowa City, IA 52242 USA. Univ Michigan, Flint, MI 48502 USA. Univ Roma La Sapienza, Rome, Italy. Ist Nazl Fis Nucl, Rome, Italy. Univ Sao Paulo, Sao Paulo, Brazil. Univ Trieste, Trieste, Italy. Ist Nazl Fis Nucl, Trieste, Italy. RP Molchanov, VV (reprint author), Inst High Energy Phys, Protvino, Russia. RI Zukanovich Funchal, Renata/C-5829-2013; Russ, James/P-3092-2014; Gulmez, Erhan/P-9518-2015; Gouffon, Philippe/I-4549-2012; Maleev, Victor/R-4140-2016; OI Zukanovich Funchal, Renata/0000-0001-6749-0022; Russ, James/0000-0001-9856-9155; Gulmez, Erhan/0000-0002-6353-518X; Gouffon, Philippe/0000-0001-7511-4115; iori, maurizio/0000-0002-6349-0380 NR 32 TC 9 Z9 9 U1 0 U2 2 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 NOV 29 PY 2001 VL 521 IS 3-4 BP 171 EP 180 DI 10.1016/S0370-2693(01)01194-7 PG 10 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 495VB UT WOS:000172360100007 ER PT J AU Cheng, HC Matchev, KT Wang, J AF Cheng, HC Matchev, KT Wang, J TI GUT breaking on the lattice SO PHYSICS LETTERS B LA English DT Article ID SUPERSYMMETRY BREAKING; SYMMETRY-BREAKING; EXTRA DIMENSIONS; GAUGE; MODELS AB We construct a supersymmetric grand unified model in the framework of a latticized extra dimension. The SU(5) symmetries on the lattice are broken by the vacuum expectation values of the link fields connecting adjacent SU(5) sites, leaving just the MSSM at low energies. Below the SU(5) breaking scale, the theory gives rise to a similar spectrum as in orbifold breaking of SU(5) symmetry in 5 dimensions, and shares many features with the latter scenario. We discuss gauge coupling unification and proton decay emphasizing the differences with respect to the usual grand unified theories. Our model may be viewed as an effective four-dimensional description of the orbifold symmetry breaking in higher dimensions. (C) 2001 Published by Elsevier Science B.V. C1 Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. CERN, Div Theory, CH-1211 Geneva 23, Switzerland. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Cheng, HC (reprint author), Univ Chicago, Enrico Fermi Inst, 5640 S Ellis Ave, Chicago, IL 60637 USA. NR 28 TC 39 Z9 39 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 NOV 29 PY 2001 VL 521 IS 3-4 BP 308 EP 314 DI 10.1016/S0370-2693(01)01205-9 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 495VB UT WOS:000172360100025 ER PT J AU Maroni, VA Epperson, SJ AF Maroni, VA Epperson, SJ TI An in situ infrared spectroscopic investigation of the pyrolysis ethylene glycol encapsulated in silica sodalite SO VIBRATIONAL SPECTROSCOPY LA English DT Article DE socialite; ethylene glycol; pyrolysis; infrared spectroscopy; diffuse reflectance ID ALUMINOSILICATE SODALITES; PURE-SILICA AB The thermal stability and pyrolysis of ethylene glycol (EG) encapsulated in the socialite cages of all-silica sodalite were studied by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and transmission infrared spectroscopy. Evidence for the presence of encapsulated CO2 formed as a result of partial decomposition of EG molecules was observed starting at about 600 K. Complete, irreversible pyrolysis of the EG occurred between 675 and 775 K. After treatment at 775 K, the CO remained encapsulated in the sodalite framework, even though there were spectroscopic indications that the pyrolysis caused a disordering of the sodalite framework. There appeared to be a temperature dependence of the conformational interactions of the EG O-H groups up to 600 K, which was mainly manifested as a weakening of intramolecular hydrogen bonding. The only detectable encapsulated products of the EG decomposition in an inert (N-2 or Ar) environment were CO and a carbonaceous (coke- or soot-like) residue. There was no evidence of other encapsulated products, such as CO, H-2, H2O, or light hydrocarbons. (C) 2001 Elsevier Science B.V All rights reserved. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Maroni, VA (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave,Bldg 205, Argonne, IL 60439 USA. NR 13 TC 9 Z9 9 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0924-2031 J9 VIB SPECTROSC JI Vib. Spectrosc. PD NOV 29 PY 2001 VL 27 IS 1 BP 43 EP 51 DI 10.1016/S0924-2031(01)00122-9 PG 9 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 491ZC UT WOS:000172139600004 ER PT J AU Mowery, DL McCormick, RL AF Mowery, DL McCormick, RL TI Deactivation of alumina supported and unsupported PdO methane oxidation catalyst: the effect of water on sulfate poisoning SO APPLIED CATALYSIS B-ENVIRONMENTAL LA English DT Article DE methane oxidation; engine exhaust; catalyst poisoning; sulfur oxides; palladium ID PALLADIUM CATALYSTS; PROPANE OXIDATION; GAMMA-ALUMINA; COMBUSTION; SO2; PARTICLES; DIOXIDE AB This study presents results for water and SO2 deactivation of unsupported PdO during methane combustion. Results of IR studies on alumina, unsupported PdO, and a 6 wt.% Pd/alumina catalyst are also presented. For methane combustion using Pd supported on alumina, SO2 in dry gas causes both inhibition and deactivation for methane oxidation. Activity studies at 733 and 793 K indicate that activity loss was greater and occurs more rapidly when both water and SO2 are present. For unsupported PdO, exposure to SO2 causes irreversible and rapid deactivation in both dry and wet environments. In situ IR studies demonstrate that for PdO supported on alumina the formation of PdSO4, Al-2(SO4)(3), and surface aluminum sulfate occur more rapidly when both SO2 and water are present. Palladium sulfate is also observed for unsupported PdO, and X-ray diffraction of deactivated catalysts indicates the presence of Pd-0, even though reactions were conducted in excess oxygen. It is proposed that under dry conditions the alumina surface scavenges SO2, slowing the formation of PdSO4. When water is present SO2 is displaced from the alumina surface and spillover of SO2 from PdO to the alumina is inhibited leading to a higher rate of formation of PdSO4. A process whereby sulfation of the PdO particle surface and reduction of the particle core to PdO can occur is proposed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Colorado Sch Mines, Colorado Inst Fuels & Engine Res, Dept Chem Engn & Petr Refining, Golden, CO 80401 USA. RP McCormick, RL (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI McCormick, Robert/B-7928-2011 NR 30 TC 74 Z9 76 U1 3 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-3373 J9 APPL CATAL B-ENVIRON JI Appl. Catal. B-Environ. PD NOV 28 PY 2001 VL 34 IS 4 BP 287 EP 297 DI 10.1016/S0926-3373(01)00222-3 PG 11 WC Chemistry, Physical; Engineering, Environmental; Engineering, Chemical SC Chemistry; Engineering GA 495XE UT WOS:000172365000004 ER PT J AU McLaughlin, BM Kirby, KP Smith, R Brickhouse, N Liedahl, DA AF McLaughlin, BM Kirby, KP Smith, R Brickhouse, N Liedahl, DA TI Electron collisional excitation of the low-lying fine-structure levels in oxygen-like Fe18+ SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID IMPACT EXCITATION; IRON PROJECT; ATOMIC DATA; FE-XIX; TRANSITIONS; COMPLEX; LINES; XXI AB Effective collision strengths for electron impact excitation of all fine-structure levels arising from the 1s(2)2s(2)2p(4) ground state configuration of oxygen-like iron ions, Fe18+ (Fe XIX), have been calculated over a range of temperatures applicable to many laboratory and astrophysical plasmas. The R-matrix method, within the semi-relativistic Breit-Pauli approximation, was employed. Twenty fine-structure levels arising from twelve 1s(2)2s(2)2p(4), 1s(2)2s2p(5), 1s(2)2p(6) and 1s(2)2s(2)2p(3)3s LSpi target terms were included in the electron scattering calculation. Comparisons of the present results, which exhibit strong resonance structure in the cross sections, with previous results obtained by distorted wave methods show significant differences. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP McLaughlin, BM (reprint author), Queens Univ Belfast, Sch Math & Phys, Belfast BT7 1NN, Antrim, North Ireland. OI Brickhouse, Nancy/0000-0002-8704-4473 NR 21 TC 5 Z9 5 U1 0 U2 0 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 NOV 28 PY 2001 VL 34 IS 22 BP 4521 EP 4529 AR PII S0953-4075(01)24905-0 DI 10.1088/0953-4075/34/22/318 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 554EW UT WOS:000175721900025 ER PT J AU Covington, AM Aguilar, A Davis, VT Alvarez, I Bryant, HC Cisneros, C Halka, M Hanstorp, D Hinojosa, G Schlachter, AS Thompson, JS Pegg, DJ AF Covington, AM Aguilar, A Davis, VT Alvarez, I Bryant, HC Cisneros, C Halka, M Hanstorp, D Hinojosa, G Schlachter, AS Thompson, JS Pegg, DJ TI Correlated processes in inner-shell photodetachment of the Na- ion SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID NEGATIVE-IONS; LI AB We have measured the total cross section for photodetachment of the Na- ion over the photon energy range 30-51 eV. Electron detachment leads predominantly to the production of Na+ ions in this energy range. The structures in the measured cross section are associated with correlated processes involving the detachment or excitation of a 2p core electron, processes which are often accompanied by the excitation of one or more valence electrons. The most prominent feature in the cross section is a strong resonance associated with the excitation of a 2p electron from the core and a 3s valence electron. As in previous experiments on double excitation of valence electrons, electron correlation is seen to play an important role in the dynamics of negative ions. C1 Univ Nevada, Dept Phys, Reno, NV 89557 USA. Univ Nevada, Chem Phys Programme, Reno, NV 89557 USA. US Mil Acad, Dept Phys, West Point, NY 10996 USA. Univ Nacl Autonoma Mexico, Ctr Ciencias Fis, Cuernavaca 62251, Morelos, Mexico. Univ New Mexico, Albuquerque, NM 87131 USA. Portland State Univ, Dept Phys, Portland, OR 97229 USA. Chalmers, Dept Phys, SE-41296 Gothenburg, Sweden. Univ Gothenburg, SE-41296 Gothenburg, Sweden. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Covington, AM (reprint author), Univ Nevada, Dept Phys, Reno, NV 89557 USA. NR 9 TC 30 Z9 30 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD NOV 28 PY 2001 VL 34 IS 22 BP L735 EP L740 AR PII S0953-4075(01)29021-X DI 10.1088/0953-4075/34/22/105 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 554EW UT WOS:000175721900005 ER PT J AU Weisman, JL Head-Gordon, M AF Weisman, JL Head-Gordon, M TI Origin of substituent effects in the absorption spectra of peroxy radicals: Time dependent density functional theory calculations SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID FIRST EXCITED-STATES; COUPLED-CLUSTER; OPEN-SHELL; ELECTRONIC-TRANSITIONS; GAS-PHASE; APPROXIMATION; KINETICS AB We investigate the assignment of electronic transitions in alkyl peroxy radicals. Past experimental work has shown that the phenyl peroxy radical exhibits a transition in the visible region; however. previous high level calculations have not reproduced this observed absorption. We use time dependent density functional theory (TDDFT) to characterize the electronic excitations of the phenyl peroxy radical as well as other hydrocarbon substituted peroxy radicals. TDDFT calculations of the phenyl peroxy radical support an excitation in the visible spectrum. Further, we investigate the nature of this visible absorption using electron attachment/detachment density diagrams of the peroxy radicals and present a qualitative picture of the origin of the visible absorption based on molecular orbital perturbations. The peroxy radical substituent is also compared against isoelectronic radical groups. The visible absorption is determined to be dependent on mixing of the alkyl and radical substituent orbitals. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Head-Gordon, M (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 35 TC 41 Z9 41 U1 1 U2 4 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 NOV 28 PY 2001 VL 123 IS 47 BP 11686 EP 11694 DI 10.1021/ja011368e PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 496HC UT WOS:000172389300022 PM 11716726 ER PT J AU Rak, J Skurski, P Simons, J Gutowski, M AF Rak, J Skurski, P Simons, J Gutowski, M TI Low-energy tautomers and conformers of neutral and protonated arginine SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID MOLECULAR-ORBITAL METHODS; GAUSSIAN-TYPE BASIS; GAS-PHASE; SEMIEMPIRICAL METHODS; GLYCINE ZWITTERION; ORGANIC-MOLECULES; ACID ZWITTERIONS; OPTIMIZATION; PARAMETERS; EXCHANGE AB The relative stabilities of zwitterionic and canonical forms of neutral arginine and of its protonated derivative were studied by using ab initio electronic structure methods. Trial structures were first identified at the PM3 level of theory with use of a genetic algorithm to systematically vary geometrical parameters. Further geometry optimizations of these structures were performed at the MP2 and B3LYP levels of theory with basis sets of the 6-31++G** quality. The final energies were determined at the CCSD/6-31++G** level and corrected for thermal effects determined at the B3LYP level. Two new nonzwitterionic structures of the neutral were identified, and one of them is the lowest energy structure found so far. The five lowest energy structures of neutral arginine are all nonzwitterionic in nature and are clustered within a narrow energy range of 2.3 kcal/mol. The lowest energy zwitterion structure is less stable than the lowest nonzwitterion structure by 4.0 kcal/mol. For no level of theory is a zwitterion structure suggested to be the global minimum. The calculated proton affinity of 256.3 kcal/mol and gas-phase basicity of 247.8 kcal/mol of arginine are in reasonable agreement with the measured values of 251.2 and 240.6 kcal/mol, respectively. The calculated vibrational characteristics of the low-energy structures of neutral arginine provide an alternative interpretation of the IR-CRLAS spectrum. C1 Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. Univ Utah, Dept Chem, Henry Eyring Ctr Theoret Chem, Salt Lake City, UT 84112 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Gutowski, M (reprint author), Univ Gdansk, Dept Chem, Ul Sobieskiego 18, PL-80952 Gdansk, Poland. NR 50 TC 124 Z9 125 U1 0 U2 12 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 NOV 28 PY 2001 VL 123 IS 47 BP 11695 EP 11707 DI 10.1021/ja011357l PG 13 WC Chemistry, Multidisciplinary SC Chemistry GA 496HC UT WOS:000172389300023 PM 11716727 ER PT J AU Du, XL Wang, WR Kim, R Yakota, H Nguyen, H Kim, SH AF Du, XL Wang, WR Kim, R Yakota, H Nguyen, H Kim, SH TI Crystal structure and mechanism of catalysis of a pyrazinamidase from Pyrococcus horikoshii SO BIOCHEMISTRY LA English DT Article ID RESISTANT MYCOBACTERIUM-TUBERCULOSIS; N-CARBAMOYLSARCOSINE AMIDOHYDROLASE; PNCA MUTATIONS; ESCHERICHIA-COLI; ARTHROBACTER SP; PROTEIN; MAD; OVEREXPRESSION; IDENTIFICATION; SMEGMATIS AB Bacterial pyrazinamidase (PZAase)/nicotinamidase converts pyrazinamide (PZA) to ammonia and pyrazinoic acid, which is active against Mycobacterium tuberculosis. Loss of PZAase activity is the major mechanism of pyrazinamide-resistance by M. tuberculosis. We have determined the crystal structure of the gene product of Pyrococcus horikoshii 999 (PH999), a PZAase, and its complex with zinc ion by X-ray crystallography. The overall fold of PH999 is similar to that of N-carbamoylsarcosine amidohydrolase (CSHase) of Arthrobacter sp. and YcaC of Escherichia coli, a protein with unknown physiological function. The active site of PH999 was identified by structural features that are also present in the active sites of CSHase and YcaC: a triad (D10, K94, and C133) and a cis-peptide (between V128 and A129). Surprisingly, a metal ion-binding site was revealed in the active site and subsequently confirmed by crystal structure of PH999 in complex with Zn2+. The roles of the triad, cis-peptide, and metal ion in the catalysis are proposed. Because of extensive homology between PH999 and PZAase of M. tuberculosis (37% sequence identity), the structure of PH999 provides a structural basis for understanding PZA-resistance by M. tuberculosis harboring PZAase mutations. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Kim, SH (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 36 TC 59 Z9 64 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD NOV 27 PY 2001 VL 40 IS 47 BP 14166 EP 14172 DI 10.1021/bi0115479 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 497PP UT WOS:000172464900006 PM 11714269 ER PT J AU Santer, BD Wigley, TML Doutriaux, C Boyle, JS Hansen, JE Jones, PD Meehl, GA Roeckner, E Sengupta, S Taylor, KE AF Santer, BD Wigley, TML Doutriaux, C Boyle, JS Hansen, JE Jones, PD Meehl, GA Roeckner, E Sengupta, S Taylor, KE TI Accounting for the effects of volcanoes and ENSO in comparisons of modeled and observed temperature trends SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ANTHROPOGENIC OZONE DEPLETION; SOUTHERN-OSCILLATION INDEX; GENERAL-CIRCULATION MODEL; TRANSIENT CLIMATE-CHANGE; SURFACE AIR-TEMPERATURE; EL-NINO; 20TH-CENTURY TEMPERATURE; AEROSOL VARIATIONS; PINATUBO ERUPTION; TIME-SERIES AB Several previous studies have attempted to remove the effects of explosive volcanic eruptions and El Nino-Southern Oscillation (ENSO) variability from time series of globally averaged surface and tropospheric temperatures. Such work has largely ignored the nonzero correlation between volcanic signals and ENSO. Here we account for this, collinearity using an iterative procedure. We remove estimated volcano and ENSO signals from the observed global mean temperature data, and then calculate trends over 1979-1999 in the residuals. Residual trends are sensitive to the choice of index used for removing ENSO effects and to uncertainties in key volcanic parameters. Despite these sensitivities, residual surface and lower tropospheric (2LT) trends are almost always larger than trends in the raw observational data. After removal of volcano and ENSO effects, the differential warming between the surface and lower troposphere is generally reduced. These results suggest that the net effect of volcanoes and ENSO over 1979-1999 was to reduce globally averaged surface and tropospheric temperatures and cool the troposphere by more than the surface. ENSO and incomplete volcanic forcing effects can hamper reliable assessment of the true correspondence between modeled and observed trends. In the second part of our study, we remove these effects from model data and compare simulated and observed residual trends. Residual temperature trends are not significantly different at the surface. In the lower troposphere the statistical significance of trend differences depends on the experiment considered, the choice of ENSO index, and the volcanic signal decay time. The simulated difference between surface and tropospheric warming rates is significantly smaller than observed in 51 out of 54 cases considered. We also examine multiple realizations of model experiments with relatively complete estimates of natural and anthropogenic forcing. ENSO and volcanic. effects are not removed from these integrations. As in the case of residual trends, model and observed raw trends are in good agreement at the surface but differ significantly in terms of the trend differential between the surface and lower troposphere. Observed and simulated lower tropospheric trends are not significantly different in 17 out of 24 cases. Our study highlights the large uncertainties inherent in removing volcano and ENSO effects from atmospheric temperature data. It shows that statistical removal of these effects improves the, correspondence between modeled and observed temperature trends over the satellite era. Accounting for volcanoes and ENSO cannot fully explain the observed warming of the surface relative to the lower troposphere, or why this differential warming is not reproduced in the model simulations considered here. C1 Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA 94550 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Univ E Anglia, Climat Res Unit, Norwich NR4 7TJ, Norfolk, England. Natl Ctr Atmospher Res, Boulder, CO 80303 USA. Max Planck Inst Meteorol, D-20146 Hamburg, Germany. Lawrence Livermore Natl Lab, Engn Directorate, Livermore, CA 94550 USA. RP Santer, BD (reprint author), Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, POB 808,Mail Stop L-264, Livermore, CA 94550 USA. EM santer1@llnl.gov RI Wigley, Tom/B-4705-2008; Jones, Philip/C-8718-2009; Taylor, Karl/F-7290-2011; Santer, Benjamin/F-9781-2011 OI Jones, Philip/0000-0001-5032-5493; Taylor, Karl/0000-0002-6491-2135; NR 62 TC 65 Z9 65 U1 2 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 27 PY 2001 VL 106 IS D22 BP 28033 EP 28059 DI 10.1029/2000JD000189 PG 27 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 495TE UT WOS:000172355800001 ER PT J AU Philipona, R Dutton, EG Stoffel, T Michalsky, J Reda, I Stifter, A Wendling, P Wood, N Clough, SA Mlawer, EJ Anderson, G Revercomb, HE Shippert, TR AF Philipona, R Dutton, EG Stoffel, T Michalsky, J Reda, I Stifter, A Wendling, P Wood, N Clough, SA Mlawer, EJ Anderson, G Revercomb, HE Shippert, TR TI Atmospheric longwave irradiance uncertainty: Pyrgeometers compared to an absolute sky-scanning radiometer, atmospheric emitted radiance interferometer, and radiative transfer model calculations SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CLIMATE RESEARCH; WAVE-RADIATION; CALIBRATION; ACCURACY AB Because atmospheric longwave radiation is one of the most fundamental elements of an expected climate change, there has been a strong interest in improving measurements and model calculations in recent years. Important questions are how reliable and consistent are atmospheric longwave radiation measurements and calculations and what are the uncertainties? The First International Pyrgeometer and Absolute Sky-scanning Radiometer Comparison, which was held at the Atmospheric Radiation Measurement program's Southern Great Plains site in Oklahoma, answers these questions at least for midlatitude summer conditions and reflects the state of the art for atmospheric longwave radiation measurements and calculations. The 15 participating pyrgeometers were all calibration-traced standard instruments chosen from a broad international community. Two new chopped pyrgeometers also took part in the comparison. An absolute sky-scanning radiometer (ASR), which includes a pyroelectric detector and a reference blackbody source, was used for the first time as a reference standard instrument to field calibrate pyrgeometers during clear-sky nighttime measurements. Owner-provided and uniformly determined blackbody calibration factors were compared. Remarkable improvements and higher pyrgeometer precision were achieved with field calibration factors. Results of nighttime and daytime pyrgeometer precision and absolute uncertainty are presented for eight consecutive days of measurements, during which period downward longwave irradiance varied between 260 and 420 W m(-2). Comparisons between pyrgeometers and the absolute ASR, the atmospheric emitted radiance interferometer, and radiative transfer models LBLRTM and MODTRAN show a surprisingly good agreement of <2 W m(-2) for nighttime atmospheric longwave irradiance measurements and calculations. C1 Phys Meteorol Observatorium Davos, World Radiat Ctr, CH-7260 Davos, Switzerland. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. SUNY Albany, Atmospher Sci Res Ctr, Albany, NY 12203 USA. DLR, Inst Atmospher Phys, D-82234 Oberpfaffenhofen, Germany. Univ Colorado, NOAA, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA. Atmospher & Environm Res Inc, Lexington, MA 02421 USA. Univ Wisconsin, Ctr Space Sci & Engn, Madison, WI 53706 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Colorado, CIRES, Boulder, CO 80309 USA. RP Philipona, R (reprint author), Phys Meteorol Observatorium Davos, World Radiat Ctr, Dorfstr 33, CH-7260 Davos, Switzerland. EM rphilipona@pmodwrc.ch; edutton@cmdl.noaa.gov; thomas_stoffel@nrel.gov; joe@asrc.cestm.albany.edu; ibrahim_reda@nrel.gov; peter.wendling@dlr.de; nwood@cwdl.noaa.gov; clough@aer.com; mlawer@aer.com; ganderson@plh.af.mil; hankr@ssec.wisc.edu; timothy.shippert@pnl.gov NR 22 TC 63 Z9 63 U1 2 U2 13 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 NOV 27 PY 2001 VL 106 IS D22 BP 28129 EP 28141 DI 10.1029/2000JD000196 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 495TE UT WOS:000172355800008 ER PT J AU Light, TE Suszcynsky, DM Jacobson, AR AF Light, TE Suszcynsky, DM Jacobson, AR TI Coincident radio frequency and optical emissions from lightning, observed with the FORTE satellite SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TRANSIONOSPHERIC PULSE PAIRS; RETURN STROKES; INTERFEROMETRIC OBSERVATIONS; ELECTRIC-FIELD; WAVE-FORMS; VHF; PHENOMENOLOGY; SIGNATURES; CLOUDS; INTRACLOUD AB We present long optical and radio frequency (RF) time series of lightning events observed with the FORTE satellite in January 2000. Each record contains multiple RF and optical impulses. We use the RF signatures to identify the general type of discharge for each impulse according, to the discrimination techniques described by Suszcynsky et al, (2000) and reviewed herein. We see a large number of paired, impulsive events in the RF which allow us to study the heights within clouds of several events, We also see that the rate of RF/optical coincidence depends on the type of discharge: nearly 100% of VHF signals from first negative return strokes have an associated optical signal, whereas a mere 50% of impulsive intracloud events appear to have an optical counterpart. While the RF signals from ground strokes clearly coincide with simple optical signals in almost all cases, the intracloud lightning often shows nearly continuous, complicated RF and optical emissions which do not cleanly correlate with one another. The RF and optical pulses do not show a well-defined relationship of intensities, for any lightning type. The observed delay between the RF and optical pulses we interpret as mainly an effect of the scattering experienced by the light as it traverses the cloud. For intracloud lightning, we find no evidence of an intrinsic delay at the source between the onset of the RF and optical signals. Impulsive in-cloud RF events are seen to occur on average every 0.9 ms during a flash. C1 Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. RP Light, TE (reprint author), Los Alamos Natl Lab, Space & Atmospher Sci Grp, NIS-1,Mail Stop D466, Los Alamos, NM 87545 USA. EM tlavezzi@lanl.gov; dsuszcynsky@lanl.gov; ajacobson@lanl.gov NR 26 TC 21 Z9 22 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 NOV 27 PY 2001 VL 106 IS D22 BP 28223 EP 28231 DI 10.1029/2001JD000727 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 495TE UT WOS:000172355800015 ER PT J AU Ramanathan, V Crutzen, PJ Lelieveld, J Mitra, AP Althausen, D Anderson, J Andreae, MO Cantrell, W Cass, GR Chung, CE Clarke, AD Coakley, JA Collins, WD Conant, WC Dulac, F Heintzenberg, J Heymsfield, AJ Holben, B Howell, S Hudson, J Jayaraman, A Kiehl, JT Krishnamurti, TN Lubin, D McFarquhar, G Novakov, T Ogren, JA Podgorny, IA Prather, K Priestley, K Prospero, JM Quinn, PK Rajeev, K Rasch, P Rupert, S Sadourny, R Satheesh, SK Shaw, GE Sheridan, P Valero, FPJ AF Ramanathan, V Crutzen, PJ Lelieveld, J Mitra, AP Althausen, D Anderson, J Andreae, MO Cantrell, W Cass, GR Chung, CE Clarke, AD Coakley, JA Collins, WD Conant, WC Dulac, F Heintzenberg, J Heymsfield, AJ Holben, B Howell, S Hudson, J Jayaraman, A Kiehl, JT Krishnamurti, TN Lubin, D McFarquhar, G Novakov, T Ogren, JA Podgorny, IA Prather, K Priestley, K Prospero, JM Quinn, PK Rajeev, K Rasch, P Rupert, S Sadourny, R Satheesh, SK Shaw, GE Sheridan, P Valero, FPJ TI Indian Ocean Experiment: An integrated analysis of the climate forcing and effects of the great Indo-Asian haze SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CLOUD CONDENSATION NUCLEI; ANTHROPOGENIC SULFATE AEROSOLS; GLOBAL RADIATION BUDGET; ATMOSPHERIC AEROSOLS; CARBONACEOUS AEROSOLS; AIRBORNE MEASUREMENTS; STRATOCUMULUS CLOUDS; TROPOSPHERIC AEROSOL; EFFECTIVE RADIUS; NATIONAL CENTER AB Every year, from December to April, anthropogenic haze spreads over most of the North Indian Ocean, and South and Southeast Asia. The Indian Ocean Experiment (INDOEX) documented this Indo-Asian haze at scales ranging from individual particles to its contribution to the regional climate forcing. This study integrates the multiplatform. observations (satellites, aircraft, ships, surface stations, and balloons) with one- and four-dimensional models to derive the regional aerosol forcing resulting from the direct, the semidirect and the two indirect effects. The haze particles consisted of several inorganic and carbonaceous species, including absorbing black carbon clusters, fly ash, and mineral dust. The most striking result was the large loading of aerosols over most of the South Asian region and the North Indian Ocean. The January to March 1999 visible optical depths were about 0.5 over most of the continent and reached values as large as 0.2 over the equatorial Indian ocean due to long-range transport. The aerosol layer extended as high as 3 km. Black carbon contributed about 14% to the fine particle mass and 11% to the visible optical depth. The single-scattering albedo estimated by several independent methods was consistently around 0.9 both inland and over the open ocean. Anthropogenic sources contributed as much as 80% (+/- 10%) to the aerosol loading and the optical depth. The in situ data, which clearly support the existence of the first indirect effect (increased aerosol concentration producing more cloud drops with smaller effective radii), are used to develop a composite indirect effect scheme. The Indo-Asian aerosols impact the radiative forcing through a complex set of heating (positive forcing) and cooling (negative forcing) processes. Clouds and black carbon emerge as the ma or players. The dominant factor, however, is the large negative forcing (-20 +/- 4 W m(-2)) at the surface and the comparably large atmospheric heating. Regionally, the absorbing haze decreased the surface solar radiation by an amount comparable to 50% of the total ocean heat flux and nearly doubled the lower tropospheric solar heating. We demonstrate with a general circulation model how this additional heating significantly perturbs the tropical rainfall patterns and the hydrological cycle with implications to global climate. C1 Univ Calif San Diego, Scripps Inst Oceanog, Ctr Atmospher Sci, La Jolla, CA 92037 USA. Max Planck Inst Chem, D-55020 Mainz, Germany. Natl Phys Lab, New Delhi 110012, India. Inst Tropospher Res, D-04318 Leipzig, Germany. Arizona State Univ, Dept Geol & Chem, Tempe, AZ 85287 USA. Indiana Univ, Dept Chem, Bloomington, IN 47401 USA. Georgia Inst Technol, Sch Civil & Environm Engn, Atlanta, GA 30332 USA. Univ Hawaii, Dept Oceanog, Honolulu, HI 96822 USA. Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Lab Sci Climat & Environm, F-91191 Gif Sur Yvette, France. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Nevada, Desert Res Inst, Reno, NV 89506 USA. Phys Res Lab, Ahmadabad 380009, Gujarat, India. Florida State Univ, Dept Meteorol, Tallahassee, FL 32306 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NOAA, Climate Monitoring & Diagnost Lab, Boulder, CO 80303 USA. Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Miami, FL 33149 USA. NOAA, Pacific Marine Environm Lab, Seattle, WA 98115 USA. Vikram Sarabhai Space Ctr, Space Phys Lab, Trivandrum 695022, Kerala, India. Meteorol Dynam Lab, F-75005 Paris, France. Univ Alaska Fairbanks, Inst Geophys, Fairbanks, AK 99775 USA. RP Ramanathan, V (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Ctr Atmospher Sci, La Jolla, CA 92037 USA. EM ram@fiji.ucsd.edu RI Heymsfield, Andrew/E-7340-2011; Crutzen, Paul/F-6044-2012; Prather, Kimberly/A-3892-2008; Collins, William/J-3147-2014; Ogren, John/M-8255-2015; Andreae, Meinrat/B-1068-2008; Lelieveld, Johannes/A-1986-2013; Quinn, Patricia/R-1493-2016 OI Prospero, Joseph/0000-0003-3608-6160; McFarquhar, Greg/0000-0003-0950-0135; Prather, Kimberly/0000-0003-3048-9890; Collins, William/0000-0002-4463-9848; Ogren, John/0000-0002-7895-9583; Andreae, Meinrat/0000-0003-1968-7925; Quinn, Patricia/0000-0003-0337-4895 NR 87 TC 782 Z9 809 U1 10 U2 158 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 NOV 27 PY 2001 VL 106 IS D22 BP 28371 EP 28398 DI 10.1029/2001JD900133 PG 28 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 495TE UT WOS:000172355800026 ER PT J AU Schmidt, TJ Stamenkovic, V Attard, GA Markovic, NM Ross, PN AF Schmidt, TJ Stamenkovic, V Attard, GA Markovic, NM Ross, PN TI On the behavior of Pt(111)-Bi in acid and alkaline electrolytes SO LANGMUIR LA English DT Article ID IRREVERSIBLY ADSORBED BISMUTH; DEFINED PLATINUM SURFACES; SINGLE-CRYSTAL SURFACES; UNDERPOTENTIAL DEPOSITION; HYDROGEN ADSORPTION; OXYGEN-ADSORPTION; CARBON-MONOXIDE; REDOX BEHAVIOR; CO ADSORPTION; FORMIC-ACID AB We studied the base voltammetry of Pt(111) modified by irreversibly adsorbed Bi in both 0.1 M HClO4 and 0.1 M NaOH. By comparing the cyclic voltammograms in both electrolytes for the same Bi-ir coverages, we found the following. (i) For highly Bi-ir covered surfaces, significantly higher ll pd coverages are found in alkaline solution, indicating that the H-upd charge cannot be unambiguously correlated to the Bi-ir coverage. (ii) In line with our previous model of enhanced adsorption of OHad on Pt sites adjacent to Bi-ir, we also propose the enhanced formation of surface oxide layers on Pt(111)-Bi-ir electrodes. CO stripping experiments on surfaces with different Bi-ir surface coverages in perchloric acid showed that on a highly Bi covered Pt(111) surface the CO oxidation starts at higher potentials than On a surface with lower Bi coverage. This finding implies that in the Langmuir-Hinshelwood surface reaction for CO oxidation both reaction partners compete for the same adsorption sites, that is, Pt(111)-Bi-ir does not represent a bifunctional surface. C1 Cardiff Univ, Dept Chem, Cardiff CF10 3TB, S Glam, Wales. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Schmidt, TJ (reprint author), Paul Scherrer Inst, Villigen, Switzerland. RI Schmidt, Thomas/A-2586-2010 OI Schmidt, Thomas/0000-0002-1636-367X NR 33 TC 9 Z9 9 U1 1 U2 19 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD NOV 27 PY 2001 VL 17 IS 24 BP 7613 EP 7619 DI 10.1021/la0103160 PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 494VH UT WOS:000172306200027 ER PT J AU Liang, Y Gan, S Engelhard, M AF Liang, Y Gan, S Engelhard, M TI First step towards the growth of single-crystal oxides on Si: Formation of a two-dimensional crystalline silicate on Si(001) SO APPLIED PHYSICS LETTERS LA English DT Article ID RAY PHOTOELECTRON-SPECTROSCOPY; SHIFTS; FILMS AB We have investigated the structural and chemical properties of reconstructed Sr/Si(001) surfaces at different Sr coverages using low energy electron diffraction, x-ray photoelectron spectroscopy, and scanning tunneling microscopy. The results show that upon low temperature oxidation and subsequent UHV annealing of the Sr/Si(001)-(2x1) surface, a crystalline Sr2SiO4 silicate-like layer formed. Using this layer as a template, single-crystal SrO thin films were grown on Si(001) substrates. Our results provide microscopic and spectroscopic evidence of the formation of a uniform, stable, two-dimensional crystalline silicate that can be used for growth of single-crystal oxides on Si(001) substrates. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Liang, Y (reprint author), Motorola Labs, 7700 S River Pkwy, Tempe, AZ 85284 USA. RI Engelhard, Mark/F-1317-2010; OI Engelhard, Mark/0000-0002-5543-0812 NR 16 TC 49 Z9 51 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 26 PY 2001 VL 79 IS 22 BP 3591 EP 3593 DI 10.1063/1.1415372 PG 3 WC Physics, Applied SC Physics GA 493CL UT WOS:000172204400011 ER PT J AU Ren, Y Price, DL AF Ren, Y Price, DL TI Neutron scattering study of H-2 adsorption in single-walled carbon nanotubes SO APPLIED PHYSICS LETTERS LA English DT Article ID HYDROGEN ADSORPTION; STORAGE; PORES AB H-2 adsorption in single-walled carbon nanotubes (SWCNTs) has been studied with quasielastic and inelastic neutron scattering. At 80 K, under a H-2 pressure of 110 atm, H-2 molecules gradually condense in the SWCNT sample. After pumping out at 25 K and 20 mTorr, the remaining H-2 molecules show a quantum rotational transition at 14.5 +/-0.1 meV, with a peak width that increases linearly with increasing temperature from 4.2 to 35 K. The H-2 molecules remain in the sample up to 65 K and then start to desorb with increasing temperature. A broad inelastic scattering spectrum from the adsorbed hydrogen is also observed. The time scale of the dynamics is longer than 15 ps even at 200 K. Our results imply that hydrogen molecules are physisorbed in the interstitial tunnels of the SWCNT bundles. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Ren, Y (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Price, David Long/A-8468-2013 NR 16 TC 49 Z9 50 U1 2 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 26 PY 2001 VL 79 IS 22 BP 3684 EP 3686 DI 10.1063/1.1421639 PG 3 WC Physics, Applied SC Physics GA 493CL UT WOS:000172204400042 ER PT J AU Diagne, M He, Y Zhou, H Makarona, E Nurmikko, AV Han, J Waldrip, KE Figiel, JJ Takeuchi, T Krames, M AF Diagne, M He, Y Zhou, H Makarona, E Nurmikko, AV Han, J Waldrip, KE Figiel, JJ Takeuchi, T Krames, M TI Vertical cavity violet light emitting diode incorporating an aluminum gallium nitride distributed Bragg mirror and a tunnel junction SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; HIGH-REFLECTIVITY; LASER; WAVELENGTHS; WAVE AB We have designed and implemented a vertical cavity violet light emitting diode which features an optical resonator composed of an in situ grown GaN/AlGaN DBR and a high reflectivity dielectric mirror. The active InGaN MQW medium is grown directly atop the AlGaN DBR and the structure includes an intracavity lateral current spreading layer based on a p(++)/n(++) InGaN/GaN tunnel junction. Electroluminescence shows directional emission, with modal linewidths as narrow as 0.6 nm. (C) 2001 American Institute of Physics. C1 Brown Univ, Div Engn, Providence, RI 02912 USA. Brown Univ, Dept Phys, Providence, RI 02912 USA. Sandia Natl Labs, Albuquerque, NM 87111 USA. Agilent Technol Labs, Palo Alto, CA 94304 USA. Lumileds Lighting, San Jose, CA 95131 USA. RP Diagne, M (reprint author), Brown Univ, Div Engn, Providence, RI 02912 USA. NR 13 TC 73 Z9 75 U1 2 U2 14 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 26 PY 2001 VL 79 IS 22 BP 3720 EP 3722 DI 10.1063/1.1415405 PG 3 WC Physics, Applied SC Physics GA 493CL UT WOS:000172204400054 ER PT J AU Fadley, CS Van Hove, MA Kaduwela, A Omori, S Zhao, L Marchesini, S AF Fadley, CS Van Hove, MA Kaduwela, A Omori, S Zhao, L Marchesini, S TI Photoelectron and x-ray holography by contrast: enhancing image quality and dimensionality SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID RANGE-MAGNETIC-ORDER; ATOMIC-RESOLUTION; FLUORESCENCE HOLOGRAPHY; MULTIPLE-SCATTERING; CIRCULAR-DICHROISM; DIFFRACTION DATA; PHOTOEMISSION; TRANSITION; MNO(001); PATTERNS AB Three forms of electron or x-ray holography 'by contrast' are discussed: they all exploit small changes in diffraction conditions to improve image quality and/or extract additional information. Spin-polarized photoelectron holography subtracts spin-down from spin-up holograms so as to image the relative orientations of atomic magnetic moments around an emitter atom. Differential photoelectron holography subtracts holograms taken at slightly different energies so as to overcome the forward-scattering problem that normally degrades the three-dimensional imaging of atoms, particularly for emitter atoms that are part of a bulk substrate environment. Resonant x-ray fluorescence holography also subtracts holograms at slightly different energies, these being chosen above and below an absorption edge of a constituent atom, thus allowing the selective imaging of that type of atom, or what has been referred to as imaging 'in true colour'. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Tokyo, Inst Ind Sci, Minato Ku, Tokyo 1068558, Japan. Sony Corp, Semicond Network Co, Atsugi, Kanagawa 2430014, Japan. RP Fadley, CS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Marchesini, Stefano/A-6795-2009; Van Hove, Michel/A-9862-2008; OI Van Hove, Michel/0000-0002-8898-6921; Kaduwela, Ajith/0000-0002-7236-2698 NR 53 TC 20 Z9 20 U1 0 U2 1 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 NOV 26 PY 2001 VL 13 IS 47 BP 10517 EP 10532 DI 10.1088/0953-8984/13/47/301 PG 16 WC Physics, Condensed Matter SC Physics GA 505YP UT WOS:000172943400002 ER PT J AU Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Palano, A Chen, GP Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Reinertsen, PL Stugu, B Abbott, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Clark, AR Gill, MS Gritsan, A Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kluth, S Kolomensky, YG Kral, JF LeClerc, C Levi, ME Liu, T Lynch, G Meyer, AB Momayezi, M Oddone, PJ Perazzo, A Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Bright-Thomas, PG Harrison, TJ Hawkes, CM Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, K Koch, H Krug, J Kunze, M Lewandowski, B Peters, K Schmuecker, H Steinke, M Andress, JC Barlow, NR Bhimji, W Chevalier, N Clark, PJ Cottingham, WN De Groot, N Dyce, N Foster, B McFall, JD Wallom, D Wilson, FF Abe, K Hearty, C Mattison, TS McKenna, JA Thiessen, D Jolly, S McKemey, AK Tinslay, J Blinov, VE Bukin, AD Bukin, DA Buzykaev, AR Golubev, VB Ivanchenko, VN Korol, AA Kravchenko, EA Onuchin, AP Salnikov, AA Serednyakov, SI Skovpen, YI Telnov, VI Yushkov, AN Best, D Lankford, AJ Mandelkern, M McMahon, S Stoker, DP Ahsan, A Arisaka, K Buchanan, C Chun, S Branson, JG MacFarlane, DB Prell, S Rahatlou, S Raven, G Sharma, V Campagnari, C Dahmes, B Hart, PA Kuznetsova, N Levy, SL Long, O Lu, A Richman, JD Verkerke, W Witherell, M Yellin, S Beringer, J Dorfan, DE Eisner, AM Frey, A Grillo, AA Grothe, M Heusch, CA Johnson, RP Kroeger, W Lockman, WS Pulliam, T Sadrozinski, H Schalk, T Schmitz, RE Schumm, BA Seiden, A Turri, M Walkowiak, W Williams, DC Wilson, MG Chen, E Dubois-Felsmann, GP Dvoretskii, A Hitlin, DG Metzler, S Oyang, J Porter, FC Ryd, A Samuel, A Weaver, M Yang, S Zhu, RY Devmal, S Geld, TL Jayatilleke, S Mancinelli, G Meadows, BT Sokoloff, MD Barillari, T Bloom, P Dima, MO Fahey, S Ford, WT Hall, TL Johnson, DR Nauenberg, U Olivas, A Park, H Rankin, P Roy, J Sen, S Smith, JG van Hoek, WC Wagner, DL Blouw, J Harton, JL Krishnamurthy, M Soffer, A Toki, WH Wilson, RJ Zhang, J Brandt, T Brose, J Colberg, T Dahlinger, G Dickopp, M Dubitzky, RS Maly, E Muller-Pfefferkorn, R Otto, S Schubert, KR Schwierz, R Spaan, B Wilden, L Behr, L Bernard, D Bonneaud, GR Brochard, F Cohen-Tanugi, J Ferrag, S Roussot, E T'Jampens, S Thiebaux, C Vasileiadis, G Verderi, M Anjomshoaa, A Bernet, R Khan, A Muheim, F Playfer, S Swain, JE Falbo, M Borean, C Bozzi, C Dittongo, S Folegani, M Piemontese, L Treadwell, E Anulli, F Baldini-Ferroli, R Calcaterra, A de Sangro, R Falciai, D Finocchiaro, G Patteri, P Peruzzi, IM Piccolo, M Xie, Y Zallo, A Bagnasco, S Buzzo, A Contri, R Crosetti, G Fabbricatore, P Farinon, S Lo Vetere, M Macri, M Monge, MR Musenich, R Pallavicini, M Parodi, R Passaggio, S Pastore, FC Patrignani, C Pia, MG Priano, C Robutti, E Santroni, A Morii, M Bartoldus, R Dignan, T Hamilton, R Mallik, U Cochran, J Crawley, HB Fischer, PA Lamsa, J Meyer, WT Rosenberg, EI Benkebil, M Grosdidier, G Hast, C Hocker, A Lacker, HM LePeltier, V Lutz, AM Plaszczynski, S Schune, MH Trincaz-Duvoid, S Valassi, A Wormser, G Bionta, RM Brigljevic, V Lange, DJ Mugge, M Shi, X van Bibber, K Wenaus, TJ Wright, DM Wuest, CR Carroll, M Fry, JR Gabathuler, E Gamet, R George, M Kay, M Payne, DJ Sloane, RJ Touramanis, C Aspinwall, ML Bowerman, DA Dauncey, PD Egede, U Eschrich, I Gunawardane, NJW Nash, JA Sanders, P Smith, D Azzopardi, DE Back, JJ Dixon, P Harrison, PF Potter, RJL Shorthouse, HW Strother, P Vidal, PB Williams, MI Cowan, G George, S Green, MG Kurup, A Marker, CE McGrath, P McMahon, TR Ricciardi, S Salvatore, F Scott, I Vaitsas, G Brown, D Davis, CL Allison, J Barlow, RJ Boyd, JT Forti, A Fullwood, J Jackson, F Lafferty, GD Savvas, N Simopoulos, ET Weatherall, JH Farbin, A Jawahery, A Lillard, V Olsen, J Roberts, DA Schieck, JR Blaylock, G Dallapiccola, C Flood, KT Hertzbach, SS Kofler, R Moore, TB Staengle, H Willocq, S Brau, B Cowan, R Sciolla, G Taylor, F Yamamoto, RK Milek, M Patel, PM Trischuk, J Lanni, F Palombo, F Bauer, JM Booke, M Cremaldi, L Eschenburg, V Kroeger, R Reidy, J Sanders, DA Summers, DJ Martin, JP Nief, JY Seitz, R Taras, P Zacek, V Nicholson, H Sutton, CS Cartaro, C Cavallo, N De Nardo, G Fabozzi, F Gatto, C Lista, L Paolucci, P Piccolo, D Sciacca, C LoSecco, JM Alsmiller, JRG Gabriel, TA Handler, T Brau, J Frey, R Iwasaki, M Sinev, NB Strom, D Colecchia, F Dal Corso, F Dorigo, A Galeazzi, F Margoni, M Michelon, G Morandin, M Posocco, M Rotondo, M Simonetto, F Stroili, R Torassa, E Voci, C Benayoun, M Briand, H Chauveau, J David, P De la Vaissiere, C Del Buono, L Hamon, O Le Diberder, F Leruste, P Lory, J Roos, L Stark, J Versille, S Manfredi, PF Re, V Speziali, V Frank, ED Gladney, L Guo, QH Panetta, JH Angelini, C Batignani, G Bettarini, S Bondioli, M Carpinelli, M Forti, F Giorgi, MA Lusiani, A Martinez-Vidal, F Morganti, M Neri, N Paoloni, E Rama, M Rizzo, G Sandrelli, F Simi, G Triggiani, G Walsh, J Haire, M Judd, D Paick, K Turnbull, L Wagoner, DE Albert, J Bula, C Elmer, P Lu, C McDonald, KT Miftakov, V Schaffner, SF Smith, AJS Tumanov, A Varnes, EW Cavoto, G del Re, D Faccini, R Ferrarotto, F Ferroni, F Fratini, K Lamanna, E Leonardi, E Mazzoni, MA Morganti, S Piredda, G Tehrani, FS Serra, M Voena, C Christ, S Waldi, R Adye, T Franek, B Geddes, NI Gopal, GP Xella, SM Aleksan, R De Domenico, G Emery, S Gaidot, A Ganzhur, SF Giraud, PF de Monchenault, GH Kozanecki, W Langer, M London, GW Mayer, B Serfass, B Vasseur, G Yeche, C Zito, M Copty, N Purohit, MV Singh, H Yumiceva, FX Adam, I Anthony, PL Aston, D Baird, K Bloom, E Boyarski, AM Bulos, F Calderini, G Claus, R Convery, MR Coupal, DP Coward, DH Dorfan, J Doser, M Dunwoodie, W Field, RC Glanzman, T Godfrey, GL Gowdy, SJ Grosso, P Himel, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Moffeit, KC Mount, R Muller, DR O'Grady, CP Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Rochester, LS Roodman, A Schietinger, T Schindler, RH Schwiening, J Serbo, VV Snyder, A Soha, A Spanier, SM Stelzer, J Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, PR Cheng, CH Kirkby, D Meyer, TI Roat, C Henderson, R Bugg, W Cohn, H Weidemann, AW Izen, JM Kitayama, I Lou, XC Turcotte, M Bianchi, F Bona, M Di Girolamo, B Gamba, D Smol, A Zanin, D Lanceri, L Pompili, A Vuagnin, G Panvini, RS Brown, CM De Silva, A Kowalewski, R Roney, JM Band, HR Charles, E Dasu, S Di Lodovico, F Eichenbaum, AM Hu, H Johnson, JR Liu, R Nielsen, J Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, SL Yu, Z Zobernig, H Kordich, TMB Neal, H AF Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Palano, A Chen, GP Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Reinertsen, PL Stugu, B Abbott, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Clark, AR Gill, MS Gritsan, A Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kluth, S Kolomensky, YG Kral, JF LeClerc, C Levi, ME Liu, T Lynch, G Meyer, AB Momayezi, M Oddone, PJ Perazzo, A Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Bright-Thomas, PG Harrison, TJ Hawkes, CM Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, K Koch, H Krug, J Kunze, M Lewandowski, B Peters, K Schmuecker, H Steinke, M Andress, JC Barlow, NR Bhimji, W Chevalier, N Clark, PJ Cottingham, WN De Groot, N Dyce, N Foster, B McFall, JD Wallom, D Wilson, FF Abe, K Hearty, C Mattison, TS McKenna, JA Thiessen, D Jolly, S McKemey, AK Tinslay, J Blinov, VE Bukin, AD Bukin, DA Buzykaev, AR Golubev, VB Ivanchenko, VN Korol, AA Kravchenko, EA Onuchin, AP Salnikov, AA Serednyakov, SI Skovpen, YI Telnov, VI Yushkov, AN Best, D Lankford, AJ Mandelkern, M McMahon, S Stoker, DP Ahsan, A Arisaka, K Buchanan, C Chun, S Branson, JG MacFarlane, DB Prell, S Rahatlou, S Raven, G Sharma, V Campagnari, C Dahmes, B Hart, PA Kuznetsova, N Levy, SL Long, O Lu, A Richman, JD Verkerke, W Witherell, M Yellin, S Beringer, J Dorfan, DE Eisner, AM Frey, A Grillo, AA Grothe, M Heusch, CA Johnson, RP Kroeger, W Lockman, WS Pulliam, T Sadrozinski, H Schalk, T Schmitz, RE Schumm, BA Seiden, A Turri, M Walkowiak, W Williams, DC Wilson, MG Chen, E Dubois-Felsmann, GP Dvoretskii, A Hitlin, DG Metzler, S Oyang, J Porter, FC Ryd, A Samuel, A Weaver, M Yang, S Zhu, RY Devmal, S Geld, TL Jayatilleke, S Mancinelli, G Meadows, BT Sokoloff, MD Barillari, T Bloom, P Dima, MO Fahey, S Ford, WT Hall, TL Johnson, DR Nauenberg, U Olivas, A Park, H Rankin, P Roy, J Sen, S Smith, JG van Hoek, WC Wagner, DL Blouw, J Harton, JL Krishnamurthy, M Soffer, A Toki, WH Wilson, RJ Zhang, J Brandt, T Brose, J Colberg, T Dahlinger, G Dickopp, M Dubitzky, RS Maly, E Muller-Pfefferkorn, R Otto, S Schubert, KR Schwierz, R Spaan, B Wilden, L Behr, L Bernard, D Bonneaud, GR Brochard, F Cohen-Tanugi, J Ferrag, S Roussot, E T'Jampens, S Thiebaux, C Vasileiadis, G Verderi, M Anjomshoaa, A Bernet, R Khan, A Muheim, F Playfer, S Swain, JE Falbo, M Borean, C Bozzi, C Dittongo, S Folegani, M Piemontese, L Treadwell, E Anulli, F Baldini-Ferroli, R Calcaterra, A de Sangro, R Falciai, D Finocchiaro, G Patteri, P Peruzzi, IM Piccolo, M Xie, Y Zallo, A Bagnasco, S Buzzo, A Contri, R Crosetti, G Fabbricatore, P Farinon, S Lo Vetere, M Macri, M Monge, MR Musenich, R Pallavicini, M Parodi, R Passaggio, S Pastore, FC Patrignani, C Pia, MG Priano, C Robutti, E Santroni, A Morii, M Bartoldus, R Dignan, T Hamilton, R Mallik, U Cochran, J Crawley, HB Fischer, PA Lamsa, J Meyer, WT Rosenberg, EI Benkebil, M Grosdidier, G Hast, C Hocker, A Lacker, HM LePeltier, V Lutz, AM Plaszczynski, S Schune, MH Trincaz-Duvoid, S Valassi, A Wormser, G Bionta, RM Brigljevic, V Lange, DJ Mugge, M Shi, X van Bibber, K Wenaus, TJ Wright, DM Wuest, CR Carroll, M Fry, JR Gabathuler, E Gamet, R George, M Kay, M Payne, DJ Sloane, RJ Touramanis, C Aspinwall, ML Bowerman, DA Dauncey, PD Egede, U Eschrich, I Gunawardane, NJW Nash, JA Sanders, P Smith, D Azzopardi, DE Back, JJ Dixon, P Harrison, PF Potter, RJL Shorthouse, HW Strother, P Vidal, PB Williams, MI Cowan, G George, S Green, MG Kurup, A Marker, CE McGrath, P McMahon, TR Ricciardi, S Salvatore, F Scott, I Vaitsas, G Brown, D Davis, CL Allison, J Barlow, RJ Boyd, JT Forti, A Fullwood, J Jackson, F Lafferty, GD Savvas, N Simopoulos, ET Weatherall, JH Farbin, A Jawahery, A Lillard, V Olsen, J Roberts, DA Schieck, JR Blaylock, G Dallapiccola, C Flood, KT Hertzbach, SS Kofler, R Moore, TB Staengle, H Willocq, S Brau, B Cowan, R Sciolla, G Taylor, F Yamamoto, RK Milek, M Patel, PM Trischuk, J Lanni, F Palombo, F Bauer, JM Booke, M Cremaldi, L Eschenburg, V Kroeger, R Reidy, J Sanders, DA Summers, DJ Martin, JP Nief, JY Seitz, R Taras, P Zacek, V Nicholson, H Sutton, CS Cartaro, C Cavallo, N De Nardo, G Fabozzi, F Gatto, C Lista, L Paolucci, P Piccolo, D Sciacca, C LoSecco, JM Alsmiller, JRG Gabriel, TA Handler, T Brau, J Frey, R Iwasaki, M Sinev, NB Strom, D Colecchia, F Dal Corso, F Dorigo, A Galeazzi, F Margoni, M Michelon, G Morandin, M Posocco, M Rotondo, M Simonetto, F Stroili, R Torassa, E Voci, C Benayoun, M Briand, H Chauveau, J David, P De la Vaissiere, C Del Buono, L Hamon, O Le Diberder, F Leruste, P Lory, J Roos, L Stark, J Versille, S Manfredi, PF Re, V Speziali, V Frank, ED Gladney, L Guo, QH Panetta, JH Angelini, C Batignani, G Bettarini, S Bondioli, M Carpinelli, M Forti, F Giorgi, MA Lusiani, A Martinez-Vidal, F Morganti, M Neri, N Paoloni, E Rama, M Rizzo, G Sandrelli, F Simi, G Triggiani, G Walsh, J Haire, M Judd, D Paick, K Turnbull, L Wagoner, DE Albert, J Bula, C Elmer, P Lu, C McDonald, KT Miftakov, V Schaffner, SF Smith, AJS Tumanov, A Varnes, EW Cavoto, G del Re, D Faccini, R Ferrarotto, F Ferroni, F Fratini, K Lamanna, E Leonardi, E Mazzoni, MA Morganti, S Piredda, G Tehrani, FS Serra, M Voena, C Christ, S Waldi, R Adye, T Franek, B Geddes, NI Gopal, GP Xella, SM Aleksan, R De Domenico, G Emery, S Gaidot, A Ganzhur, SF Giraud, PF de Monchenault, GH Kozanecki, W Langer, M London, GW Mayer, B Serfass, B Vasseur, G Yeche, C Zito, M Copty, N Purohit, MV Singh, H Yumiceva, FX Adam, I Anthony, PL Aston, D Baird, K Bloom, E Boyarski, AM Bulos, F Calderini, G Claus, R Convery, MR Coupal, DP Coward, DH Dorfan, J Doser, M Dunwoodie, W Field, RC Glanzman, T Godfrey, GL Gowdy, SJ Grosso, P Himel, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Moffeit, KC Mount, R Muller, DR O'Grady, CP Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Rochester, LS Roodman, A Schietinger, T Schindler, RH Schwiening, J Serbo, VV Snyder, A Soha, A Spanier, SM Stelzer, J Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, PR Cheng, CH Kirkby, D Meyer, TI Roat, C Henderson, R Bugg, W Cohn, H Weidemann, AW Izen, JM Kitayama, I Lou, XC Turcotte, M Bianchi, F Bona, M Di Girolamo, B Gamba, D Smol, A Zanin, D Lanceri, L Pompili, A Vuagnin, G Panvini, RS Brown, CM De Silva, A Kowalewski, R Roney, JM Band, HR Charles, E Dasu, S Di Lodovico, F Eichenbaum, AM Hu, H Johnson, JR Liu, R Nielsen, J Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, SL Yu, Z Zobernig, H Kordich, TMB Neal, H CA BABAR Collaboration TI Measurements of the branching fractions of exclusive charmless B meson decays with eta ' or omega mesons SO PHYSICAL REVIEW LETTERS LA English DT Article ID CP-VIOLATION; MECHANISM; SEARCH AB We present the results of searches for B decays to charmless two-body final states containing eta' or omega mesons, based on 20.7 fb(-1) of data collected with the BABAR detector. We find the branching fractions B(B+ --> eta' K+) = (70 +/- 8 +/- 5) x 10(-6), B(B-o --> eta' K-o) = (42(-11)(+13) +/- 4) x 10(-6) and B(B+ --> omega pi (+)) = (6.6(-1.8)(+2.1) +/- 0.7) x 10(-6), where the first error quoted is statistical and the second is systematic. We give measurements of four additional modes for which the 90% confidence level upper limits are B(B+ --> eta' pi (+)) < 12 x 10(-6), B(B+ --> omegaK(+)) < 4 x 10(-6), B(B-o --> omegaK(o)) < 13 x 10(-6), and B (B-o --> omega pi (o)) < 3 x 10(-6). C1 Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France. Univ Bari, Dipartimento Fis, I-70126 Bari, Italy. Ist Nazl Fis Nucl, I-70126 Bari, Italy. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Bergen, Inst Phys, N-5007 Bergen, Norway. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Ruhr Univ Bochum, Inst Expt Phys 1, D-44780 Bochum, Germany. Univ Bristol, Bristol BS8 1TL, Avon, England. Univ British Columbia, Vancouver, BC V6T 1Z1, Canada. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. CALTECH, Pasadena, CA 91125 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Colorado, Boulder, CO 80309 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Tech Univ Dresden, Inst Kern & Teilchenphys, D-01062 Dresden, Germany. Ecole Polytech, F-91128 Palaiseau, France. Univ Edinburgh, Edinburgh EH9 3JZ, Midlothian, Scotland. Elon Univ, Elon College, NC 27244 USA. Univ Ferrara, Dipartimento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, I-44100 Ferrara, Italy. Florida A&M Univ, Tallahassee, FL 32307 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy. Ist Nazl Fis Nucl, I-16146 Genoa, Italy. Harvard Univ, Cambridge, MA 02138 USA. Univ Iowa, Iowa City, IA 52242 USA. Iowa State Univ, Ames, IA 50011 USA. Lab Accelerateur Lineaire, F-91898 Orsay, France. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. Univ London Imperial Coll Sci Technol & Med, London SW7 2BW, England. Univ London Queen Mary Coll, London E1 4NS, England. Univ London Royal Holloway & Bedford New Coll, Egham TW20 0EX, Surrey, England. Univ Louisville, Louisville, KY 40292 USA. Univ Manchester, Manchester M13 9PL, Lancs, England. Univ Maryland, College Pk, MD 20742 USA. Univ Massachusetts, Amherst, MA 01003 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. McGill Univ, Montreal, PQ H3A 2T8, Canada. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Ist Nazl Fis Nucl, I-20133 Milan, Italy. Univ Mississippi, University, MS 38677 USA. Univ Montreal, Lab Rene JA Levesque, Montreal, PQ H3C 3J7, Canada. Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Naples Federico II, Dipartimento Sci Fis, I-80126 Naples, Italy. Ist Nazl Fis Nucl, I-80126 Naples, Italy. Univ Notre Dame, Notre Dame, IN 46556 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Padua, Dipartimento Fis, I-35131 Padua, Italy. Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Paris 06, LPNHE, F-75252 Paris, France. Univ Paris 07, LPNHE, F-75252 Paris, France. Univ Pavia, Dipartimento Elettron, I-27100 Pavia, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Scuola Normale Super Pisa, I-56010 Pisa, Italy. Ist Nazl Fis Nucl, I-56010 Pisa, Italy. Prairie View A&M Univ, Prairie View, TX 77446 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Univ Rostock, D-18051 Rostock, Germany. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CEA Saclay, DAPNIA, F-91191 Gif Sur Yvette, France. Univ S Carolina, Columbia, SC 29208 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Stanford, CA 94305 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ Tennessee, Knoxville, TN 37996 USA. Univ Texas, Richardson, TX 75083 USA. Univ Turin, Dipartimento Fis, I-10125 Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Trieste, Dipartimento Fis, I-34127 Trieste, Italy. Ist Nazl Fis Nucl, I-34127 Trieste, Italy. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Victoria, Victoria, BC V8W 3P6, Canada. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. Univ Perugia, I-06100 Perugia, Italy. Univ Basilicata, I-85100 Potenza, Italy. RP Aubert, B (reprint author), Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France. RI Cavallo, Nicola/F-8913-2012; Patrignani, Claudia/C-5223-2009; Monge, Maria Roberta/G-9127-2012; Kravchenko, Evgeniy/F-5457-2015; Martinez Vidal, F*/L-7563-2014; Kolomensky, Yury/I-3510-2015; Lo Vetere, Maurizio/J-5049-2012; Lamanna, Ernesto/C-7658-2012; Pallavicini, Marco/G-5500-2012; Lusiani, Alberto/N-2976-2015; Lusiani, Alberto/A-3329-2016; Morandin, Mauro/A-3308-2016; Valassi, Andrea/K-7506-2012; Peters, Klaus/C-2728-2008; Telnov, Valery/C-6900-2009; de Groot, Nicolo/A-2675-2009; Lista, Luca/C-5719-2008; Schaffner, Stephen/D-1189-2011; Frank, Edward/A-8865-2012; Pia, Maria Grazia/C-7034-2012; Torassa, Ezio/I-1788-2012; Forti, Francesco/H-3035-2011; Rotondo, Marcello/I-6043-2012; de Sangro, Riccardo/J-2901-2012; Di Lodovico, Francesca/L-9109-2016; Calcaterra, Alessandro/P-5260-2015; Frey, Raymond/E-2830-2016 OI Patrignani, Claudia/0000-0002-5882-1747; Monge, Maria Roberta/0000-0003-1633-3195; Martinez Vidal, F*/0000-0001-6841-6035; Kolomensky, Yury/0000-0001-8496-9975; Lo Vetere, Maurizio/0000-0002-6520-4480; Lamanna, Ernesto/0000-0002-7844-8230; Pallavicini, Marco/0000-0001-7309-3023; Lusiani, Alberto/0000-0002-6876-3288; Lusiani, Alberto/0000-0002-6876-3288; Morandin, Mauro/0000-0003-4708-4240; Valassi, Andrea/0000-0001-9322-9565; Peters, Klaus/0000-0001-7133-0662; Telnov, Valery/0000-0002-8312-8119; Pia, Maria Grazia/0000-0002-3579-9639; Forti, Francesco/0000-0001-6535-7965; Rotondo, Marcello/0000-0001-5704-6163; de Sangro, Riccardo/0000-0002-3808-5455; Di Lodovico, Francesca/0000-0003-3952-2175; Calcaterra, Alessandro/0000-0003-2670-4826; Frey, Raymond/0000-0003-0341-2636 NR 20 TC 43 Z9 43 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 NOV 26 PY 2001 VL 87 IS 22 BP art. no. EP 221802 DI 10.1103/PhysRevLett.87.221802 PG 7 WC Physics, Multidisciplinary SC Physics GA 496VB UT WOS:000172416800009 ER PT J AU Ideguchi, E Sarantites, DG Reviol, W Afanasjev, AV Devlin, M Baktash, C Janssens, RVF Rudolph, D Axelsson, A Carpenter, MP Galindo-Uribarri, A LaFosse, DR Lauritsen, T Lerma, F Lister, CJ Reiter, P Seweryniak, D Weiszflog, M Wilson, JN AF Ideguchi, E Sarantites, DG Reviol, W Afanasjev, AV Devlin, M Baktash, C Janssens, RVF Rudolph, D Axelsson, A Carpenter, MP Galindo-Uribarri, A LaFosse, DR Lauritsen, T Lerma, F Lister, CJ Reiter, P Seweryniak, D Weiszflog, M Wilson, JN TI Superdeformation in the doubly magic nucleus Ca-40(20)20 SO PHYSICAL REVIEW LETTERS LA English DT Article ID SHELL-MODEL; MEAN-FIELD; ROTATIONAL BANDS; MASS REGION; GAMMASPHERE; COEXISTENCE; NI-56 AB A rotational band with seven gamma -ray transitions between states with spin 2 (h) over bar and 16 (h) over bar has been observed in the doubly magic, self-conjugate nucleus Ca-40(20)20. The measured transition quadrupole moment of 1.80(-0.29)(+0.39)eb indicates a superdeformed shape with a deformation beta (2) = 0.59(-0.07)(+0.11). The features of this band are explained by cranked relativistic mean field calculations to arise from an 8-particle 8-hole excitation. C1 Washington Univ, Dept Chem, St Louis, MO 63130 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Latvia, Lab Radiat Phys, LV-2169 Riga, Latvia. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Lund Univ, Dept Phys, S-22100 Lund, Sweden. Svedberg Lab, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Radiat Sci, S-75121 Uppsala, Sweden. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. RP Ideguchi, E (reprint author), Washington Univ, Dept Chem, St Louis, MO 63130 USA. RI Rudolph, Dirk/D-4259-2009; Carpenter, Michael/E-4287-2015; Devlin, Matthew/B-5089-2013 OI Rudolph, Dirk/0000-0003-1199-3055; Carpenter, Michael/0000-0002-3237-5734; Devlin, Matthew/0000-0002-6948-2154 NR 22 TC 159 Z9 159 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 NOV 26 PY 2001 VL 87 IS 22 BP art. no. EP 222501 DI 10.1103/PhysRevLett.87.222501 PG 4 WC Physics, Multidisciplinary SC Physics GA 496VB UT WOS:000172416800010 PM 11736396 ER PT J AU Sokolowski-Tinten, K Blome, C Dietrich, C Tarasevitch, A von Hoegen, MH von der Linde, D Cavalleri, A Squier, J Kammler, M AF Sokolowski-Tinten, K Blome, C Dietrich, C Tarasevitch, A von Hoegen, MH von der Linde, D Cavalleri, A Squier, J Kammler, M TI Femtosecond x-ray measurement of ultrafast melting and large acoustic transients SO PHYSICAL REVIEW LETTERS LA English DT Article ID SURFACTANT-MEDIATED EPITAXY; STRAIN-RELIEF; LATTICE-DYNAMICS; DIFFRACTION; GERMANIUM; SILICON; GAAS; TRANSITIONS; EXCITATION; SI(111) AB Time-resolved x-ray diffraction with ultrashort (approximate to 300 fs), multi-keV x-ray pulses has been used to study the femtosecond laser-induced solid-to-liquid phase transition in a thin crystalline layer of germanium. Nonthermal melting is observed to take place within 300-500 fs. Following ultrafast melting we observe strong acoustic perturbations evolving on a picosecond time scale. C1 Univ Essen Gesamthsch, Inst Laser & Plasmaphys, D-45117 Essen, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Hannover, Inst Halbleitertechnol, D-30167 Hannover, Germany. RP Sokolowski-Tinten, K (reprint author), Univ Essen Gesamthsch, Inst Laser & Plasmaphys, D-45117 Essen, Germany. RI Sokolowski-Tinten, Klaus/A-5415-2015 NR 23 TC 170 Z9 171 U1 4 U2 26 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 NOV 26 PY 2001 VL 87 IS 22 BP art. no. EP 225701 DI 10.1103/PhysRevLett.87.225701 PG 4 WC Physics, Multidisciplinary SC Physics GA 496VB UT WOS:000172416800022 PM 11736408 ER PT J AU Ding, H Engelbrecht, JR Wang, Z Campuzano, JC Wang, SC Yang, HB Rogan, R Takahashi, T Kadowaki, K Hinks, DG AF Ding, H Engelbrecht, JR Wang, Z Campuzano, JC Wang, SC Yang, HB Rogan, R Takahashi, T Kadowaki, K Hinks, DG TI Coherent quasiparticle weight and its connection to high-T-c superconductivity from angle-resolved photoemission SO PHYSICAL REVIEW LETTERS LA English DT Article ID VALENCE-BOND STATE; AXIS SUPERFLUID RESPONSE; DOPING DEPENDENCE; FERMI-SURFACE; BI2SR2CACU2O8+DELTA; PSEUDOGAP; TEMPERATURE; GAP; DISPERSION; BI-2212 AB We study the doping and temperature dependence of the single-particle coherent weight, z(A), for high-T-c superconductors Bi2Sr2CaCu2O8+x using angle-resolved photoemission. We find that at low temperatures the coherent weight z(A) at (pi ,0) is proportional to the carrier concentration x and that the temperature dependence of z(A) is similar to that of the c-axis superfluid density. We show that, for a wide range of carrier concentration, the superconducting transition temperature scales with the product of the low-temperature coherent weight and the maximum superconducting gap. C1 Boston Coll, Dept Phys, Chestnut Hill, MA 02467 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Tohoku Univ, Dept Phys, Sendai, Miyagi 980, Japan. Univ Tsukuba, Inst Mat Sci, Tsukuba, Ibaraki 305, Japan. RP Boston Coll, Dept Phys, Chestnut Hill, MA 02467 USA. RI Takahashi, Takashi/E-5080-2010; Tohoku, Arpes/A-4890-2010; Wang, Shancai/F-6162-2013 NR 32 TC 138 Z9 139 U1 2 U2 18 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 NOV 26 PY 2001 VL 87 IS 22 AR 227001 DI 10.1103/PhysRevLett.87.227001 PG 4 WC Physics, Multidisciplinary SC Physics GA 496VB UT WOS:000172416800032 PM 11736418 ER PT J AU Knudson, MD Hanson, DL Bailey, JE Hall, CA Asay, JR Anderson, WW AF Knudson, MD Hanson, DL Bailey, JE Hall, CA Asay, JR Anderson, WW TI Equation of state measurements in liquid deuterium to 70 GPa SO PHYSICAL REVIEW LETTERS LA English DT Article ID REFLECTED SHOCK EXPERIMENTS; INSULATOR-METAL TRANSITION; OF-STATE; DENSE HYDROGEN; TEMPERATURE-MEASUREMENTS; 1-6 MBAR; HUGONIOT; HOT; DISSOCIATION; VELOCITIES AB Using intense magnetic pressure, a method was developed to launch flyer plates to velocities in excess of 20 km/s. This technique was used to perform plate-impact, shock wave experiments on cryogenic liquid deuterium (L-D-2) to examine its high-pressure equation of state. Using an impedance matching method, Hugoniot measurements were obtained in the pressure range of 30-70 GPa. The results of these experiments disagree with previously reported Hugoniot measurements of L-D-2 in the pressure range above similar to 40 GPa, but are in good agreement with first principles, ab initio models for hydrogen and its isotopes. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 25 TC 194 Z9 204 U1 0 U2 9 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 NOV 26 PY 2001 VL 87 IS 22 AR 225501 DI 10.1103/PhysRevLett.87.225501 PG 4 WC Physics, Multidisciplinary SC Physics GA 496VB UT WOS:000172416800019 PM 11736405 ER PT J AU Pislak, S Appel, R Atoyan, GS Bassalleck, B Bergman, DR Cheung, N Dhawan, S Do, H Egger, J Eilerts, S Herold, W Issakov, VV Kaspar, H Kraus, DE Lazarus, DM Lichard, P Lowe, J Lozano, J Ma, H Majid, W Poblaguev, AA Rehak, P Sher, A Thompson, JA Truol, P Zeller, ME AF Pislak, S Appel, R Atoyan, GS Bassalleck, B Bergman, DR Cheung, N Dhawan, S Do, H Egger, J Eilerts, S Herold, W Issakov, VV Kaspar, H Kraus, DE Lazarus, DM Lichard, P Lowe, J Lozano, J Ma, H Majid, W Poblaguev, AA Rehak, P Sher, A Thompson, JA Truol, P Zeller, ME TI New measurement of Ke4(+) decay and the s-wave pi pi-scattering length a(0)(0) SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHIRAL PERTURBATION-THEORY; LOW-ENERGY; 2 LOOPS; PARAMETERS; CONSTANTS; AMPLITUDE AB A sample of 4 x 10(5) events from the decay K+ --> pi (+) pi (-) e(+)nu (e) (K-e4) has been collected in experiment E865 at the Brookhaven Alternating Gradient Synchrotron. The analysis of these data yields new measurements of the K-e4 branching ratio [(4.11 +/- 0.01 +/- 0.11) x 10(-5)], the s-wave pi pi scattering length [a(0)(0) = 0.216 +/- 0.013(stat) +/- 0.004(syst) +/- 0.005(theor)], and the form factors F, G, and H of the hadronic current and their dependence on the invariant pi pi mass. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Yale Univ, Dept Phys, New Haven, CT 06511 USA. Univ Zurich, Inst Phys, CH-8057 Zurich, Switzerland. RP Pislak, S (reprint author), Phonak AG, CH-8712 Stafa, Switzerland. RI Lichard, Peter/A-4459-2010 OI Lichard, Peter/0000-0003-1581-8545 NR 40 TC 172 Z9 174 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 NOV 26 PY 2001 VL 87 IS 22 AR 221801 DI 10.1103/PhysRevLett.87.221801 PG 4 WC Physics, Multidisciplinary SC Physics GA 496VB UT WOS:000172416800008 PM 11736394 ER PT J AU Krishnan, VV AF Krishnan, VV TI Estimating the efficiency of ensemble quantum computing SO PHYSICS LETTERS A LA English DT Article ID EFFECTIVE PURE STATES; SWAP OPERATION; NMR; COMPUTATION; SPECTROSCOPY; INFORMATION; ALGORITHM AB A straightforward method to estimate the efficiency of ensemble quantum computing using nuclear magnetic resonance spectroscopy is presented by defining a quantum computing efficiency factor (QC(epsilon)). This method allows critical evaluation of the performance of quantum gates and algorithms and provides a way to design efficient quantum computer. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program L448, Livermore, CA 94551 USA. RP Krishnan, VV (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program L448, Livermore, CA 94551 USA. RI Krishnan, Krish/A-6859-2010 NR 26 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD NOV 26 PY 2001 VL 291 IS 1 BP 27 EP 33 DI 10.1016/S0375-9601(01)00696-X PG 7 WC Physics, Multidisciplinary SC Physics GA 497NP UT WOS:000172462600006 ER PT J AU Monazam, ER Shadle, LJ Lawson, LO AF Monazam, ER Shadle, LJ Lawson, LO TI A transient method for determination of saturation carrying capacity SO POWDER TECHNOLOGY LA English DT Article DE circulating fluid bed; saturation carrying capacity; gas-solids flow; transport regimes ID FLUIDIZED-BEDS; FLOW REGIMES; CHOKING; ENTRAINMENT; FREEBOARD; PRESSURE; GAS AB Clear definition of smooth and stable operating regimes is necessary if circulating fluid bed reactors are going to be adopted commercially for process applications that require load following capabilities. One significant source of instability or long-term transient occurs when traversing the transition from transporting in a lean phase fluidization regime to transporting in a turbulent or fast-fluidized bed regime. The gas saturation carrying capacity (SCC) is the key functional parameter required to define this transition. A simple method is presented to accurately determine the SCC in which the solids flux was abruptly halted and the loss in pressure signal monitored over time. The SCC was measured for PVC under a variety of conditions. Upon drawing from the analogous liquid-vapor to vapor phase transition, a predictive relationship is also presented to estimate SCC for various gas-solid flow systems, knowing the gas velocity and solids' terminal velocity in that gas. Published by Elsevier Science B.V. C1 US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. REM Engn Serv, Morgantown, WV 26505 USA. RP Shadle, LJ (reprint author), US DOE, Natl Energy Technol Lab, M-S N04,POB 880, Morgantown, WV 26507 USA. OI Shadle, Lawrence/0000-0002-6283-3628 NR 23 TC 21 Z9 21 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD NOV 26 PY 2001 VL 121 IS 2-3 BP 205 EP 212 DI 10.1016/S0032-5910(01)00354-0 PG 8 WC Engineering, Chemical SC Engineering GA 494MU UT WOS:000172287100011 ER PT J AU Friedberg, R Lee, TD Zhao, WQ Cimenser, A AF Friedberg, R Lee, TD Zhao, WQ Cimenser, A TI A convergent iterative solution of the quantum double-well potential SO ANNALS OF PHYSICS LA English DT Article ID PERTURBATION-THEORY; INSTANTON AB We present a new convergent iterative solution for the two lowest quantum wave functions psi (ev) and psi (od) of the Hamiltonian with a quartic double-weil potential V in one dimension. By starting from a trial function, which is by itself the exact lowest even or odd eigenstate of a different Hamiltonian with a modified potential V + deltaV, we construct the Green's function for the modified potential, The true wave functions, psi (ev) or psi (od), then satisfy a linear inhomogeneous integral equation, in which the inhomogeneous term is the trial function, and the kernel is the product of the Green's function times the sum of deltaV, the potential difference, and the corresponding energy shift. By iterating this equation we obtain successive approximations to the true wave function; furthermore, the approximate energy shift is also adjusted at each iteration so that the approximate wave function is well behaved everywhere. We are able to prove that this iterative procedure converges for both the energy and the wave function at all x. The effectiveness of this iterative process clearly depends on how good the trial function is, or equivalently, how small the potential difference deltaV is. Although each iteration brings a correction smaller than the previous one by a factor proportional to the parameter that characterizes the smallness of deltaV, it is not a power series expansion in the parameter. The exact tunneling information of the modified potential is, of course, contained in the Green's function; by adjusting the kernel of the integral equation via the energy shift at each iteration, we bring enough of this information into the calculation so that each approximate wave function is exponentially tuned. This is the underlying reason why the present method converges, while the usual power series expansion does not. (C) 2001 Elsevier Science. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. CCAST, World Lab, Beijing 100080, Peoples R China. RIKEN BNL Res Ctr, Brookhaven Natl Lab, Upton, NY 11943 USA. Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China. RP Friedberg, R (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. NR 13 TC 15 Z9 15 U1 1 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-4916 J9 ANN PHYS-NEW YORK JI Ann. Phys. PD NOV 25 PY 2001 VL 294 IS 1 BP 67 EP 133 DI 10.1006/aphy.2001.6187 PG 67 WC Physics, Multidisciplinary SC Physics GA 501GQ UT WOS:000172677300004 ER PT J AU Kerstein, AR Ashurst, WT Wunsch, S Nilsen, V AF Kerstein, AR Ashurst, WT Wunsch, S Nilsen, V TI One-dimensional turbulence: vector formulation and application to free shear flows SO JOURNAL OF FLUID MECHANICS LA English DT Article ID 3-DIMENSIONAL VORTICITY EQUATION; MODEL; SIMULATION; TRANSPORT AB One-dimensional turbulence is a stochastic simulation method representing the time evolution of the velocity profile along a notional line of sight through a turbulent flow. In this paper, the velocity is treated as a three-component vector, in contrast to previous formulations involving a single velocity component. This generalization allows the incorporation of pressure-scrambling effects and provides a framework for further extensions of the model. Computed results based on two alternative physical pictures of pressure scrambling are compared to direct numerical simulations of two time-developing planar free shear flows: a mixing layer and a wake. Scrambling based on equipartition of turbulent kinetic energy on an eddy-by-eddy basis yields less accurate results than a scheme that maximizes the intercomponent energy transfer during each eddy, subject to invariance constraints. The latter formulation captures many features of free shear flow structure, energetics, and fluctuation properties, including the spatial variation of the probability density function of a passive advected scalar. These results demonstrate the efficacy of the proposed representation of vector velocity evolution on a one-dimensional domain. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Torrex Equipment Corp, Livermore, CA 94550 USA. RP Kerstein, AR (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 23 TC 52 Z9 54 U1 0 U2 8 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH ST, NEW YORK, NY 10011-4221 USA SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD NOV 25 PY 2001 VL 447 BP 85 EP 109 PG 25 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 493TN UT WOS:000172239700004 ER PT J AU Lawson, SL Jakosky, BM AF Lawson, SL Jakosky, BM TI Lunar surface thermophysical properties derived from Clementine LWIR and UVVIS images SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MOON; CALIBRATION; CAMERA AB In an effort to understand the influence of albedo and large-scale topography on remote lunar surface measurements, we investigate the relationship between measured Clementine longwave infrared (LWIR) camera temperatures and ultraviolet-visible (UVVIS) camera 750-nm reflectances. We compare the observed temperature-reflectance relationships with those predicted using a rough-surface numerical model with varying albedo. The lunar surface response in different highland and mare locations is explored as a function of varying phase angle. At very low phase angles the temperature and reflectance response is primarily governed by the variation in single-scattering albedo regardless of the presence of topography. As the phase angle increases, the influence of surface roughness grows. Finally, at moderate to high phase angles the effect of surface roughness dominates. In the absence of large-scale topography the lunar surface temperature and reflectance response at all phase angles is governed by the variation in single-scattering albedo. LWIR-measured temperature variations yield local topographic information at High incidence angles that is unavailable via the reflectance; white UVVIS-measured reflectance variations yield local topographic information at low incidence angles that is unavailable via the temperature. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80309 USA. Univ Colorado, Dept Geol Sci, Boulder, CO 80309 USA. Univ Colorado, Dept Astrophys & Planetary Sci, Boulder, CO 80309 USA. RP Lawson, SL (reprint author), Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. NR 30 TC 5 Z9 9 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD NOV 25 PY 2001 VL 106 IS E11 BP 27911 EP 27932 DI 10.1029/2000JE001391 PG 22 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 497AT UT WOS:000172431100010 ER PT J AU Blake, PC Edelstein, NM Hitchcock, PB Kot, WK Lappert, MF Shalimoff, GV Tian, S AF Blake, PC Edelstein, NM Hitchcock, PB Kot, WK Lappert, MF Shalimoff, GV Tian, S TI Synthesis, properties and structures of the tris(cyclopentadienyl)thorium(III) complexes [Th{eta(5)-C5H3(SiMe2R)(2)-1,3}(3)] (R = Me or Bu-t) SO JOURNAL OF ORGANOMETALLIC CHEMISTRY LA English DT Article DE thorium(III) cyclopentadienyls; structures; EPR spectra ID ACTINIDE COMPLEXES; CHEMISTRY AB The homoleptic, dark-blue, crystalline (disubstituted-cyclopentadienyl)thorium(III) complexes [Th{eta (5)-C5H3(SiMe2R)(2)-1,3}(3)] (R = Me 1 or 'Bu 3) were obtained in good yield from the appropriate tris(cyclopentadienyl)thorium(IV) chloride by treatment with an excess of sodium-potassium alloy in toluene at 20-35 degreesC with sonication. Complex I was also accessible by a similar reduction of [ThCp"Cl-2(2)] [Cp" = eta (5)-C5H3(SiMe3)(2)-1,3]; with possibly a transient Th(II) cyclopentadienyl as intermediate. Complex 1 with wet toluene afforded [(ThCp"(3))(2)( mu -O)] (2); it was unreactive with THF, DME, CO or H-2, but with Na-K alloy in THF it afforded a green, diamagnetic, readily oxidisable cyclopentadienylthorium complex. Complexes 1 and 3 showed singlet EPR spectra in methylcyclohexane at 298 K, whence it is concluded that they have a 6d(1) rather than a 5f(1) electronic ground state. Variable temperature EPR spectra, magnetic measurements and optical spectra of I are described and discussed. The X-ray structures of crystalline I and 3 show that each has approximate D-3h, symmetry about the Th atom, which can be regarded as bound to the centroid of each of the three cyclopentadienyl rings. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Sussex, Chem Lab, Sch Chem Phys & Environm Sci, Brighton BN1 9QJ, E Sussex, England. RP Edelstein, NM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. EM m.f.lappert@sussex.ac.uk NR 14 TC 32 Z9 32 U1 4 U2 14 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-328X J9 J ORGANOMET CHEM JI J. Organomet. Chem. PD NOV 25 PY 2001 VL 636 IS 1-2 SI SI BP 124 EP 129 DI 10.1016/S0022-328X(01)00860-9 PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 491AW UT WOS:000172086700018 ER PT J AU Osborn, DL Frank, JH AF Osborn, DL Frank, JH TI Laser-induced fragmentation fluorescence detection of the vinyl radical and acetylene SO CHEMICAL PHYSICS LETTERS LA English DT Article ID CROSS-SECTIONS; NM; SPECTROSCOPY; PHOTOLYSIS; EMISSION; METHYL; PHOTODISSOCIATION; SPECTRUM; ACETONE; KETONE AB When excited at lambda = 230 nm, the vinyl radical and acetylene may be detected via fluorescence from C-2(d(3)Pi (g) -->a(3)Pi (u)) using laser-induced fragmentation fluorescence (LIFF). Vinyl photodissociation creates C-2(d(3)Pi (g)) more efficiently than acetylene photodissociation by a factor of 1300-200 depending on the internal excitation of the vinyl radical. The key difference in LIFF efficiency between the two molecules depends on the mechanism for loss of the first H atom. This LIFF process may provide a method for probing the elusive vinyl radical in methane flames. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Osborn, DL (reprint author), Sandia Natl Labs, Combust Res Facil, Mail Stop 9055, Livermore, CA 94551 USA. RI Osborn, David/A-2627-2009 NR 25 TC 9 Z9 9 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 NOV 23 PY 2001 VL 349 IS 1-2 BP 43 EP 50 DI 10.1016/S0009-2614(01)01174-5 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 500AL UT WOS:000172603600008 ER PT J AU Chandra, T Higashi, K Suryanarayana, C Tome, C AF Chandra, T Higashi, K Suryanarayana, C Tome, C TI Proceedings of THERMEC'2000, the International Conference on Processing and Manufacturing of Advanced Materials, Las Vegas, USA, 4-8 December 2000 SO JOURNAL OF MATERIALS PROCESSING TECHNOLOGY LA English DT Editorial Material C1 Univ Wollongong, Wollongong, NSW 2500, Australia. Univ Osaka Prefecture, Osaka, Japan. Univ Cent Florida, Orlando, FL 32816 USA. Los Alamos Natl Lab, Los Alamos, NM USA. RP Chandra, T (reprint author), Univ Wollongong, Wollongong, NSW 2500, Australia. RI Suryanarayana, C/B-9314-2008 NR 0 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0924-0136 J9 J MATER PROCESS TECH JI J. Mater. Process. Technol. PD NOV 23 PY 2001 VL 117 IS 3 SI SI BP 269 EP 269 DI 10.1016/S0924-0136(01)01196-7 PG 1 WC Engineering, Industrial; Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 503MW UT WOS:000172803100001 ER PT J AU Sherby, OD Wadsworth, J AF Sherby, OD Wadsworth, J TI Ancient blacksmiths, the Iron Age, Damascus steels, and modem metallurgy SO JOURNAL OF MATERIALS PROCESSING TECHNOLOGY LA English DT Article; Proceedings Paper CT International Conference on Processing and Manufacturing of Advanced Materials (THERMEC 2000) CY DEC 04-08, 2000 CL LAS VEGAS, NEVADA DE ancient blacksmiths; iron age; Damascus steels; superplasticity; pearlite; martensite AB The history of iron and Damascus steels is described through the eyes of ancient blacksmiths. For example, evidence is presented that questions why the Iron Age could not have begun at about the same time as the early Bronze Age (i.e. approximately 7000 B.C.). It is also clear that ancient blacksmiths had enough information from their forging work, together with their observation of color changes during heating and their estimate of hardness by scratch tests, to have determined some key parts of the present-day iron-carbon phase diagram. The blacksmiths' greatest artistic accomplishments were the Damascus and Japanese steel swords. The Damascus sword was famous not only for its exceptional cutting edge and toughness, but also for its beautiful surface markings. Damascus steels are ultrahigh carbon steels (UHCSs) that contain from 1.0 to 2.1% carbon. The modem metallurgical understanding of UHCSs has revealed that remarkable properties can be obtained in these hypereutectoid steels. The results achieved in UHCSs are attributed to the ability to place the carbon, in excess of the eutectoid composition, to do useful work that enhances the high temperature processing of carbon steels and that improves the low and intermediate temperature mechanical properties. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Sherby, OD (reprint author), Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. NR 16 TC 25 Z9 30 U1 7 U2 27 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0924-0136 J9 J MATER PROCESS TECH JI J. Mater. Process. Technol. PD NOV 23 PY 2001 VL 117 IS 3 SI SI BP 347 EP 353 DI 10.1016/S0924-0136(01)00794-4 PG 7 WC Engineering, Industrial; Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 503MW UT WOS:000172803100015 ER PT J AU Boehlert, CJ Bingert, JF AF Boehlert, CJ Bingert, JF TI Microstructure, tensile, and creep behavior of O+BCCTi(2)AlNballoys processed using induction-float-zone melting SO JOURNAL OF MATERIALS PROCESSING TECHNOLOGY LA English DT Article; Proceedings Paper CT International Conference on Processing and Manufacturing of Advanced Materials (THERMEC 2000) CY DEC 04-08, 2000 CL LAS VEGAS, NEVADA DE induction-float-zone melting; microtexture; orthorhombic; body-centered cubic; orientation relationship; tension; creep ID AL-NB SYSTEM; BCC ORTHORHOMBIC ALLOYS; TITANIUM ALUMINIDE; ROOM-TEMPERATURE; O-PHASE; DEFORMATION; MECHANISMS; EVOLUTION AB The microstructure, tensile. and tensile-creep behavior were studied for orthorhombic (O) plus body-centered cubic (BCC) Ti-22Al-24Nb and Ti-26Al-27Nb (at.%) alloys processed using induction-float-zone melting (IFZM). Microstructure studies were performed using scanning and transmission electron microscopy (SEM and TEM), automated electron back-scattered diffraction (EBSD), and X-ray diffraction (XRD). Upon solidification. the BCC phase evolved with [100] oriented nearly parallel to the longitudinal rod direction. During the slow coot through the O + BCC-phase field, O-variants formed in a fine lath network within the parent BCC. The as-processed Ti26Al-27Nb rod was strongly textured with an approximately equal distribution of six resolvable O-variants. The retained BCC phase, which was sandwiched between O laths, maintained a higher volume fraction (V-f similar to 0.20) in Ti-22Al-24Nb compared to Ti-26Al-27Nb (V-t similar to 0.05). The tensile and creep behavior of the as-processed microstructures were evaluated with the tensile axis oriented parallel to the longitudinal rod direction. The fully lath O + BCC Ti-22Al-24Nb microstructure exhibited a room-temperature yield strength of 836 MPa and an elongation-to-failure of 4.5%. Surface slip traces revealed that slip was compatible between the O and BCC phases. An untransformed-BCC Ti-26Al-27Nb microstructure, oriented with [1 0 0] nearly parallel to the tensile axis, exhibited localized deformation bands resulting in an elongation of more than 5.9% and an average yield strength of 828 MPa. In terms of the creep behavior, the secondary creep rates revealed that the fully lath 0 + BCC Ti-26-Al-27Nb microstructure significantly outperformed that for all other O-based alloys. For applied stresses greater than 300 MPa, an activation energy of 346 kJ/mol and a creep exponent of 5.1 were measured, while for lower applied stresses the creep exponent transitioned to a value of 2.3. Overall, this work shows that induction-float-zone processing produces textured fully lath 0 + BCC microstructures containing an attractive balance of room- and elevated-temperature properties for A] concentrations as high as 26 at.%. Crown Copyright (C) 2001 Published by Elsevier Science B.V. All rights reserved. C1 Alfred Univ, Alfred, NY 14802 USA. Los Alamos Natl Lab, Los Alamos, NM USA. RP Boehlert, CJ (reprint author), Alfred Univ, Alfred, NY 14802 USA. NR 30 TC 9 Z9 10 U1 1 U2 13 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0924-0136 J9 J MATER PROCESS TECH JI J. Mater. Process. Technol. PD NOV 23 PY 2001 VL 117 IS 3 SI SI BP 400 EP 408 DI 10.1016/S0924-0136(01)00796-8 PG 9 WC Engineering, Industrial; Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 503MW UT WOS:000172803100025 ER PT J AU Shi, Y Liu, B Liu, L Edgar, JH Meyer, HM Payzant, EA Walker, LR Evans, ND Swadener, JG Chaudhuri, J Chaudhuri, J AF Shi, Y Liu, B Liu, L Edgar, JH Meyer, HM Payzant, EA Walker, LR Evans, ND Swadener, JG Chaudhuri, J Chaudhuri, J TI Initial nucleation study and new technique for sublimation growth of AlN on SiC substrate SO PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT 4th International Conference on Nitride Semiconductors (ICNS-4) CY JUL 16-20, 2001 CL DENVER, CO ID SINGLE-CRYSTALS; GAN FILMS; EPITAXY; LAYERS AB Single crystal platelets of AIN were successfully grown on 6H-SiC(0001) by a novel technique designed to suppress SiC decomposition, promote two-dimensional growth. ard eliminate cracking in the AIN. X-ray diffractometry and synchrotron white beam X-ray topography demonstrate that the final AIN single crystal is of high structural quality. C1 Kansas State Univ, Dept Chem Engn, Manhattan, KS 66506 USA. Oak Ridge Natl Lab, Engn Technol Div, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Wichita State Univ, Dept Mech Engn, Wichita, KS 67260 USA. RP Liu, B (reprint author), Kansas State Univ, Dept Chem Engn, Manhattan, KS 66506 USA. EM beiliu@ksu.edu RI Payzant, Edward/B-5449-2009; Evans, Neal/F-5955-2011; Chaudhuri, Jharna/E-8863-2013; OI Payzant, Edward/0000-0002-3447-2060; Swadener, John G/0000-0001-5493-3461 NR 13 TC 9 Z9 10 U1 0 U2 6 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY SN 1862-6300 EI 1862-6319 J9 PHYS STATUS SOLIDI A JI Phys. Status Solidi A-Appl. Mat. PD NOV 23 PY 2001 VL 188 IS 2 BP 757 EP 762 DI 10.1002/1521-396X(200112)188:2<757::AID-PSSA757>3.0.CO;2-S PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 503CM UT WOS:000172779700060 ER PT J AU Huang, D Visconti, P Reshchikov, MA Yun, F King, T Baski, AA Litton, CW Jasinski, J Liliental-Weber, Z Morkoc, H AF Huang, D Visconti, P Reshchikov, MA Yun, F King, T Baski, AA Litton, CW Jasinski, J Liliental-Weber, Z Morkoc, H TI Polarity of GaN grown on sapphire by molecular beam epitaxy with different buffer layers SO PHYSICA STATUS SOLIDI A-APPLIED RESEARCH LA English DT Article; Proceedings Paper CT 4th International Conference on Nitride Semiconductors (ICNS-4) CY JUL 16-20, 2001 CL DENVER, COLORADO AB We report on polarity of GaN films grown on sapphire substrates by molecular beam epitaxy using different buffer lavers and growth conditions. On high temperature AlN or GaN buffer lavers, the GaN films typically show Ga or N-polarity, respectively. When low temperature (either AlN or GaN) buffer lavers are employed, GaN films of both polarities can be grown, but these films have high density of inversion domains. Insertion of additional GaN/AlN quantum dot lavers between the buffer lavers and the GaN films provides strain relief and a significant improvement in the quality of the GaN epilayers. C1 Virginia Commonwealth Univ, Dept Elect Engn, Richmond, VA 23284 USA. Virginia Commonwealth Univ, Phys Dept, Richmond, VA 23284 USA. CNR, Ist Studio Nuovi Mat Elettron, I-73100 Lecce, Italy. USAF, Res Lab, AFRL, MLPS, Wright Patterson AFB, OH 45433 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Huang, D (reprint author), Virginia Commonwealth Univ, Dept Elect Engn, Richmond, VA 23284 USA. RI Liliental-Weber, Zuzanna/H-8006-2012; VISCONTI, PAOLO/L-7214-2015; OI VISCONTI, PAOLO/0000-0002-4058-4042; Baski, Alison/0000-0002-8985-8067 NR 4 TC 12 Z9 12 U1 1 U2 6 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0031-8965 J9 PHYS STATUS SOLIDI A JI Phys. Status Solidi A-Appl. Res. PD NOV 23 PY 2001 VL 188 IS 2 BP 571 EP 574 DI 10.1002/1521-396X(200112)188:2<571::AID-PSSA571>3.3.CO;2-6 PG 4 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 503CM UT WOS:000172779700021 ER PT J AU Bakke, T Sullivan, CT Mukherjee, SD AF Bakke, T Sullivan, CT Mukherjee, SD TI Vertically tapered core polymeric optical spot-size transformer SO ELECTRONICS LETTERS LA English DT Article AB A polymeric optical spot-size transformer (SST) With a vertically tapered core layer that enables both vertical and lateral mode expansion is described. A total fibre to waveguide insertion loss of 0.6 dB has been measured with the SST, an improvement of II dB. The I dB excess loss misalignment tolerance is +/-2.7 mum. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Norwegian Univ Sci & Technol, N-7491 Trondheim, Norway. RP Bakke, T (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 5 Z9 5 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 NOV 22 PY 2001 VL 37 IS 24 BP 1475 EP 1476 DI 10.1049/el:20010994 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 501LW UT WOS:000172687000033 ER PT J AU Hess, WP Joly, AG Gerrity, DP Beck, KM Sushko, PV Shluger, AL AF Hess, WP Joly, AG Gerrity, DP Beck, KM Sushko, PV Shluger, AL TI Selective laser desorption of ionic surfaces: Resonant surface excitation of KBr SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ELECTRON-STIMULATED DESORPTION; ALKALI-HALIDE SURFACES; AB-INITIO CALCULATIONS; EMISSION; CRYSTALS; EXCITON; MOLECULES; ENERGIES; ATOMS; PHOTODESORPTION AB We demonstrate evidence of selective laser-induced desorption of ground state Br((2)P(3/2)) and spin-orbit excited state Br((2)P(1/2)) atoms from KBr single crystals following 6.4 eV irradiation. Laser excitation tuned selectively to a surface resonance below the first bulk absorption band excites surface states preferentially leading to surface specific reactions while inducing relatively insignificant bulk reaction. The experimental results are supported by embedded cluster ab initio calculations that indicate a reduced surface exciton energy compared to that of the bulk exciton with a slight further reduction for steps and kink sites. Low fluence irradiation of cleaved KBr crystals, near the calculated surface exciton energy of 6.2 eV, produces hyperthermal Br((2)P(3/2)) emission without a significant thermal or Br((2)P(1/2)) component. The hyperthermal emission is shown theoretically to be characteristic of surface induced reaction of exciton decomposition while thermal emission is attributed to bulk photoreaction. (C) 2001 American Institute of Physics. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Reed Coll, Dept Chem, Portland, OR 97202 USA. UCL, Dept Phys & Astron, London WC1E 6BT, England. RP Hess, WP (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM wayne.hess@pnl.gov; a.shluger@ucl.ac.uk RI Sushko, Peter/F-5171-2013 OI Sushko, Peter/0000-0001-7338-4146 NR 50 TC 35 Z9 35 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 22 PY 2001 VL 115 IS 20 BP 9463 EP 9472 DI 10.1063/1.1410907 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 491UW UT WOS:000172129300038 ER PT J AU Lapinski, A Spanget-Larsen, J Langgard, M Waluk, J Radziszewski, JG AF Lapinski, A Spanget-Larsen, J Langgard, M Waluk, J Radziszewski, JG TI Raman spectrum of the phenyl radical SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID BASIS-SETS; GAS-PHASE; KINETICS; ABSORPTION; NO AB The Raman spectrum of phenyl radical (C6H5) isolated in low-temperature argon matrices has been obtained. The assignments of experimentally observed frequencies are based on comparison with results of quantum chemical calculations (B3LYP/cc-pVTZ) and with infrared absorption bands measured for (C6H5)-C-12 and (C6H5)-C-13 species. Analysis of the IR and Raman spectra, including IR linear dichroism, and of the isotopic shifts caused by C-12 --> C-13 substitution allows to reconfirm most of the previous assignments and to introduce some corrections. The prominent ring breathing mode, characteristic for benzenoid compounds (991 cm(-1) in benzene), occurs in phenyl radical at 998 cm(-1). C1 NREL, Golden, CO 80401 USA. Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA. Roskilde Univ Ctr, Dept Chem, DK-4000 Roskilde, Denmark. H Lundbeck, DK-2500 Valby, Denmark. Polish Acad Sci, Inst Phys Chem, PL-01224 Warsaw, Poland. RP Radziszewski, JG (reprint author), NREL, 1617 Cole Blvd, Golden, CO 80401 USA. RI Waluk, Jacek/C-8250-2011 NR 38 TC 20 Z9 20 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 NOV 22 PY 2001 VL 105 IS 46 BP 10520 EP 10524 DI 10.1021/jp0114900 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 497QA UT WOS:000172465900004 ER PT J AU Hathorn, BC Sumpter, BG Barnes, MD Noid, DW AF Hathorn, BC Sumpter, BG Barnes, MD Noid, DW TI Molecular dynamics simulation of collinear polymer nanoparticle collisions: Reaction and scattering SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID NORMAL-COORDINATE ANALYSIS; COMPOSITE MICROPARTICLES; MACROMOLECULAR SYSTEMS; BLEND MICROPARTICLES; OPTICAL DIFFRACTION; THERMAL-PROPERTIES; REFRACTIVE-INDEX; PARTICLES; SIZE; RELAXATION AB Collinear collisions of polyethylene nanoparticles are studied, with a particular emphasis on the transition between sticking and reactive scattering trajectories. The former are characterized by collisions where the two polymer particles form a particle dimer, the latter by collisions resulting in the gross change of particle structure, such as particle fragmentation or transfer of polymer chains from one particle to another. It is observed that in the collinear case there are no scattering trajectories where the particles undergo nearly elastic collisions and rebound with small energy change. This property is attributed to the fact that during the collision process the particles undergo reorganization, and the energy involved is difficult to recover. The result is that at all but extremely high velocities, particles undergo rapid and irreversible energy transfer from the relative translational coordinate into other internal coordinates, resulting in dimerization of the polymer particles. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Hathorn, BC (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 54 TC 3 Z9 3 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 NOV 22 PY 2001 VL 105 IS 46 BP 11468 EP 11473 DI 10.1021/jp012646z PG 6 WC Chemistry, Physical SC Chemistry GA 497QC UT WOS:000172466100015 ER PT J AU Sharma, VK O'Connor, DB Cabelli, DE AF Sharma, VK O'Connor, DB Cabelli, DE TI Sequential one-electron reduction of Fe(V) to Fe(III) by cyanide in alkaline medium SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID PREMIX PULSE-RADIOLYSIS; FERRATE(VI) OXIDATION; AQUEOUS-SOLUTIONS; HYDROXYL RADICALS; HYPERVALENT IRON; STOPPED-FLOW; AMINO-ACIDS; OH RADICALS; MECHANISM; REACTIVITY AB The reduction of Fe(V) by cyanide has been studied anaerobically in alkaline media (pH 10.55-12.10) by using a premix pulse radiolysis technique. The results demonstrated for the first time the spectroscopic evidence for sequential one-electron reductions of Fe(V) to Fe(IV) to Fe(III) in aqueous media. Rates for reductions decrease with an increase in pH and appeared to be related to deprotonation of Fe(V) and Fe(IV) species. The reactivity of the three ferrates (Fe(VI), Fe(V), and Fe(IV)) with cyanide showed that Fe(V) and Fe(IV) are approximately four- and two-orders of magnitude more reactive than Fe(VI), respectively. These rates suggest that Fe(VI) oxidations of compounds may be accelerated if reactions are performed in the presence of one-electron or two-electron reducing substrates. C1 Florida Inst Technol, Dept Chem, Melbourne, FL 32901 USA. Univ Texas, Dept Chem & Biochem, Austin, TX 78712 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Sharma, VK (reprint author), Florida Inst Technol, Dept Chem, 150 W Univ Blvd, Melbourne, FL 32901 USA. OI Sharma, Virender/0000-0002-5980-8675 NR 43 TC 27 Z9 28 U1 4 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 NOV 22 PY 2001 VL 105 IS 46 BP 11529 EP 11532 DI 10.1021/jp012223x PG 4 WC Chemistry, Physical SC Chemistry GA 497QC UT WOS:000172466100023 ER PT J AU Le Riche, R Gualandris, D Thomas, JJ Hemez, F AF Le Riche, R Gualandris, D Thomas, JJ Hemez, F TI Neural identification of non-linear dynamic structures SO JOURNAL OF SOUND AND VIBRATION LA English DT Article ID NETWORKS AB Neural networks are applied to the identification of non-linear structural dynamic systems. Two complementary problems inspired from customer surveys are successively considered. Each of them calls for a different neural approach. First, the mass of the system is identified based on acceleration recordings. Statistical experiments are carried out to simultaneously characterize optimal pre-processing of the accelerations and optimal neural network models. It is found that key features for mass identification are the fourth statistical moment and the normalized power spectral density of the acceleration. Second, two architectures of recurrent neural networks, an autoregressive and a state-space model, are derived and tested for dynamic simulations, showing higher robustness of the autoregressive form. Discussion is first based on a non-linear two-degree-of-freedom problem. Neural identification is then used to calculate the load from seven acceleration measurements on a car. Eighty three per cent of network estimations show below 5% error. (C) 2001 Academic Press. C1 INSA, CNRS, UMR 6138, Lab Mecan Rouen, F-76800 St Etienne Du Rouvray, France. PSA, Dir Rech & Innovat Automobile, F-91570 Bievres, France. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Le Riche, R (reprint author), INSA, CNRS, UMR 6138, Lab Mecan Rouen, Av Univ, F-76800 St Etienne Du Rouvray, France. NR 26 TC 17 Z9 20 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD NOV 22 PY 2001 VL 248 IS 2 BP 247 EP 265 DI 10.1006/jsvi.2001.3737 PG 19 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 495MY UT WOS:000172346000004 ER PT J AU Tellers, DM Bergman, RG AF Tellers, DM Bergman, RG TI Binding of chlorohydrocarbons to metal centers: Quantitative evaluation of relative binding constants and structural characterization of the first isolable transition metal-chloromethane adduct SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID HALOCARBONS; HALOALKANES C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Bergman, RG (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 15 TC 19 Z9 19 U1 0 U2 1 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 NOV 21 PY 2001 VL 123 IS 46 BP 11508 EP 11509 DI 10.1021/ja0164982 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 493TT UT WOS:000172240100035 PM 11707141 ER PT J AU Silva, EDE Anthony, P Arnold, R Arrighi, H Bloom, E Baughman, B Bogart, J Bosted, P Bumala, B Chekhtman, A Cotton, N Crider, A Dobbs-Dixon, I Djannati-Atai, A Dubois, R Engovatov, D Espigat, P Evans, JL Fieguth, T Flath, D Frigaard, M Giebels, B Gillespie, S Godfrey, G Grove, JE Handa, T Hansl-Kozanecka, T Hernando, J Hicks, M Hirayama, M Johnson, WN Johnson, R Kamae, T Kroeger, W Lauben, D Lin, YC Lindner, T Michelson, P Moiseev, A Nikolaou, M Nolan, P Odian, A Ohsugi, T Ormes, J Paliaga, G Parkinson, PS Phlips, B Ritz, S Rock, S Russel, JJ Sadrozinski, H Schalk, T Silvis, J Szalata, Z Terrier, R Thompson, DJ Tournear, DM Waite, AP Wallace, J Williams, S Williamson, R Winker, G AF Silva, EDE Anthony, P Arnold, R Arrighi, H Bloom, E Baughman, B Bogart, J Bosted, P Bumala, B Chekhtman, A Cotton, N Crider, A Dobbs-Dixon, I Djannati-Atai, A Dubois, R Engovatov, D Espigat, P Evans, JL Fieguth, T Flath, D Frigaard, M Giebels, B Gillespie, S Godfrey, G Grove, JE Handa, T Hansl-Kozanecka, T Hernando, J Hicks, M Hirayama, M Johnson, WN Johnson, R Kamae, T Kroeger, W Lauben, D Lin, YC Lindner, T Michelson, P Moiseev, A Nikolaou, M Nolan, P Odian, A Ohsugi, T Ormes, J Paliaga, G Parkinson, PS Phlips, B Ritz, S Rock, S Russel, JJ Sadrozinski, H Schalk, T Silvis, J Szalata, Z Terrier, R Thompson, DJ Tournear, DM Waite, AP Wallace, J Williams, S Williamson, R Winker, G TI Results from the beam test of the engineering model of the GLAST large area telescope SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE silicon microstrip detectors; space; gamma-ray AB This paper describes the results of a beam test using the Engineering Model of the GLAST Large Area Telescope, which was installed in a beam of positrons, hadrons and tagged photons at SLAC. The performance of the four subsystems, Anti Coincidence Detector, Silicon Tracker, Calorimeter and Data Acquisition will be described. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. Univ Massachusetts, Amherst, MA 01003 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Calif Santa Cruz, SCIPP, Santa Cruz, CA 95064 USA. Stanford Univ, Stanford, CA 94305 USA. Coll France, PCC, F-75231 Paris 05, France. USN, Res Lab, Washington, DC 20375 USA. Univ Washington, Seattle, WA 98195 USA. Ctr Etud Saclay, DAPNIA, DSM, CEA, Gif Sur Yvette, France. Hiroshima Univ, Dept Phys, Hiroshima 739, Japan. Royal Inst Technol, Dept Phys, SE-10044 Stockholm, Sweden. RP Silva, EDE (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. RI Nolan, Patrick/A-5582-2009; Thompson, David/D-2939-2012; Johnson, Neil/G-3309-2014; Hernando Morata, Jose Angel/L-7642-2014; OI Thompson, David/0000-0001-5217-9135; Hernando Morata, Jose Angel/0000-0002-8683-5142; Dobbs-Dixon, Ian/0000-0002-4989-6501 NR 15 TC 21 Z9 21 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 NOV 21 PY 2001 VL 474 IS 1 BP 19 EP 37 PG 19 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 495WG UT WOS:000172362900003 ER PT J AU Bindel, R Garcia, E Mignerey, AC Remsberg, LP AF Bindel, R Garcia, E Mignerey, AC Remsberg, LP TI Array of scintillator counters for PHOBOS at RHIC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE scintillator; trigger; paddle AB An array of scintillator counters ("paddle counters") for the measurement of number and energy of charged particles in heavy-ion gold-gold collisions for the PHOBOS experiment at RHIC is described. These simple, versatile, and highly efficient detectors provide a low bias and an easily understood level zero trigger. The paddle counters can also be used to select and measure event centrality. The information from the paddle counters used for triggering and event selection included the total signal height (proportional to the number of particles), the timing information of the hits, and the number of scintillators fired. The general characteristics of the paddle counters, their design parameters, and performance during the first run at RHIC are presented in this paper, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Maryland, College Pk, MD 20742 USA. RP Garcia, E (reprint author), Brookhaven Natl Lab, Phys 510D, Upton, NY 11973 USA. RI Mignerey, Alice/D-6623-2011 NR 2 TC 10 Z9 10 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 NOV 21 PY 2001 VL 474 IS 1 BP 38 EP 45 DI 10.1016/S0168-9002(01)00866-X PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 495WG UT WOS:000172362900004 ER PT J AU White, CG Jones, TD Luebke, WR Chen, YC Cheng, KC Choong, WS Kaplan, DM Nelson, K Rubin, HA Turko, B Zyla, P AF White, CG Jones, TD Luebke, WR Chen, YC Cheng, KC Choong, WS Kaplan, DM Nelson, K Rubin, HA Turko, B Zyla, P TI Upgraded DAQ system for the HyperCP experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE hyperon; HyperCP; E871; CP violation; DAQ; acquisition ID DIRECT CP VIOLATION; DECAYS; SEARCH AB The 1999 run of Fermilab E871 (HyperCP) recorded 80 Terabytes of data on 19,000 8 mm tapes with a typical trigger rate near 100 kHz. The readout electronics digitized data from 21,000 input channels with a fixed deadtime of 1.7 mus resulting in a typical livetime of 80%. The typical instantaneous rate of data generated by the HyperCP spectrometer was 36 MB/s. These data were written to tape at a sustained rate of 27 MB/s. (C) 2001 Elsevier Science B.V. All rights reserved. C1 IIT, Dept Biol Chem & Phys Sci, Div Phys, Chicago, IL 60616 USA. Lawrence Berkeley Natl Lab, Div Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Acad Sinica, Inst Phys, Taipei, Taiwan. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. RP White, CG (reprint author), IIT, Dept Biol Chem & Phys Sci, Div Phys, Chicago, IL 60616 USA. NR 25 TC 4 Z9 4 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 NOV 21 PY 2001 VL 474 IS 1 BP 67 EP 85 DI 10.1016/S0168-9002(01)00871-3 PG 19 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 495WG UT WOS:000172362900007 ER PT J AU Lee, Y Barletta, WA Leung, KN Ngo, VV Scott, P Wilcox, M Zahir, N AF Lee, Y Barletta, WA Leung, KN Ngo, VV Scott, P Wilcox, M Zahir, N TI Multi-aperture extraction system with micro-beamlet switching capability SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB A novel ion projection lithography (IPL) technique called maskless-micro-beam reduction lithography (MMRL) is being developed at the Lawrence Berkeley National Laboratory. Instead of a thin stencil mask, this new ion projection lithography scheme utilizes a thicker universal pattern generator (or beam forming electrode) which contains switchable beamlets. Both single aperture and nine-aperture beam extraction systems have been used to test the switching scheme. In the single aperture case, an ion beam current of 23 nA was extracted and successfully turned off when a positive voltage was applied on the second electrode. For the nine-hole system, ion beams were switched on and off selectively and independently from each other, It has been demonstrated that electron beam switching can be achieved in a similar manner. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Leung, KN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Ms 5-119,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 4 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD NOV 21 PY 2001 VL 474 IS 1 BP 86 EP 92 DI 10.1016/S0168-9002(01)00864-6 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 495WG UT WOS:000172362900008 ER PT J AU Arnold, R Augier, C Baker, J Barabash, A Bing, O Blum, D Brudanin, V Caffrey, AJ Campagne, JE Caurier, E Dassie, D Egorov, V Errahmane, K Filipova, T Guyonnet, JL Hubert, F Hubert, P Jullian, S Kochetov, O Kisel, I Kornoukhov, VN Kovalenko, V Kuzichev, VF Lalanne, D Laplanche, F Leccia, F Linck, I Longuemare, C Marquet, C Mauger, F Nicholson, HW Nikolic-Audit, I Pilugin, I Piquemal, F Reyss, JL Riddle, CL Sarazin, X Scheibling, F Stekl, I Suhonen, J Sutton, CS Szklarz, G Timkin, V Tretyak, V Umatov, V Vanyushin, I Vorobel, V Vylov, T AF Arnold, R Augier, C Baker, J Barabash, A Bing, O Blum, D Brudanin, V Caffrey, AJ Campagne, JE Caurier, E Dassie, D Egorov, V Errahmane, K Filipova, T Guyonnet, JL Hubert, F Hubert, P Jullian, S Kochetov, O Kisel, I Kornoukhov, VN Kovalenko, V Kuzichev, VF Lalanne, D Laplanche, F Leccia, F Linck, I Longuemare, C Marquet, C Mauger, F Nicholson, HW Nikolic-Audit, I Pilugin, I Piquemal, F Reyss, JL Riddle, CL Sarazin, X Scheibling, F Stekl, I Suhonen, J Sutton, CS Szklarz, G Timkin, V Tretyak, V Umatov, V Vanyushin, I Vorobel, V Vylov, T TI Chemical purification of molybdenum samples for the NEMO 3 experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE double beta decay; molybdenum; NEMO 3; HPGe spectrometry ID DOUBLE-BETA-DECAY; MO-100 AB Most currently, viable double beta decay experiments require highly enriched isotopic sources. These sources must be extraordinarily free of radioactive contamination. The double beta decay experiment NEMO 3 will study (100)Mo, for which physical and chemical purification techniques have been investigated. The success of the chemical purification process is discussed in the context of ultra-low background, high-purity germanium spectrometer measurements. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Mt Holyoke Coll, Dept Phys, S Hadley, MA 01075 USA. CNRS, IN2P3, IReS, F-67037 Strasbourg, France. Univ Strasbourg 1, F-67037 Strasbourg, France. CNRS, IN2P3, LAL, F-91405 Orsay, France. Univ Paris 11, F-91405 Orsay, France. INEEL, Idaho Falls, ID 83415 USA. ITEP, Moscow 117259, Russia. Joint Inst Nucl Res, Dubna 141980, Russia. CEN Bordeaux Gradignan, CNRS, IN2P3, F-33175 Gradignan, France. Univ Bordeaux 1, F-33175 Gradignan, France. CNRS, IN2P3, LPC, F-14032 Caen, France. Univ Caen, F-14032 Caen, France. CNRS, LSCE, F-91190 Gif Sur Yvette, France. FNSPE, Czech Tech Univ, Prague, Czech Republic. Univ Jyvaskyla, Jyvaskyla 40351, Finland. Charles Univ Prague, Prague, Czech Republic. RP Sutton, CS (reprint author), Mt Holyoke Coll, Dept Phys, 50 Coll St, S Hadley, MA 01075 USA. EM ssutton@mtholyoke.edu RI Caffrey, Augustine/C-2005-2009; Barabash, Alexander/S-8851-2016; OI Riddle, Catherine/0000-0002-9667-7707 NR 15 TC 11 Z9 11 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 NOV 21 PY 2001 VL 474 IS 1 BP 93 EP 100 DI 10.1016/S0168-9002(01)00869-5 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 495WG UT WOS:000172362900009 ER PT J AU Foley, B Donegan, E Silitonga, N Wignall, FS Busch, MP Delwart, EL AF Foley, B Donegan, E Silitonga, N Wignall, FS Busch, MP Delwart, EL TI Importation of multiple HIV type 1 strains into West Papua, Indonesia (Irian Jaya) SO AIDS RESEARCH AND HUMAN RETROVIRUSES LA English DT Article ID HUMAN-IMMUNODEFICIENCY-VIRUS; HETERODUPLEX MOBILITY ASSAY; INJECTING DRUG-USERS; SUBTYPE-E; SEROLOGIC CHARACTERIZATION; GUANGXI PROVINCE; GENETIC-ANALYSIS; THAILAND; EPIDEMIC; PHILIPPINES AB HIV-1 from 16 sexually transmitted disease clinic patients in Timika, West Papua, Indonesia was amplified by RT-PCR and subtyped by a combination of envelope and gag region heteroduplex mobility analysis (HMA) and direct PCR DNA sequencing. HMA showed the presence of 14 subtype E (CRF01_AE) and 2 subtype B HIV-1. Phylogenetic analysis of a 540-bp V3-V4 region of gp120 showed that 9 of 10 CRFO1_AE variants clustered tightly with a median distance of 1.3% (range, 0.5 to 2.2%) whereas 1 CRFO1_AE variant diverged significantly from the others (median distance, 10.7%; range, 10.1 to 11.8%). One subtype B virus envelope was typical of United States/European strains whereas the other appeared to be related to Thai subtype B' variants. These results reflect the independent introduction of multiple HIV-1 strains into West Papua, with the rapid spread in the majority of infected patients tested of a single strain of HIV-1E (CRF01_AE). C1 Univ Calif San Francisco, Dept Med, Blood Ctr Pacific, San Francisco, CA 94118 USA. Los Alamos Natl Lab, Los Alamos, NM 87501 USA. Univ Calif San Francisco, Dept Anesthesia, San Francisco, CA 94143 USA. Int SOS, PT Freeport, Indonesia. RP Delwart, EL (reprint author), Univ Calif San Francisco, Dept Med, Blood Ctr Pacific, 270 Masonic Ave, San Francisco, CA 94118 USA. OI Foley, Brian/0000-0002-1086-0296; Delwart, Eric/0000-0002-6296-4484 NR 26 TC 5 Z9 5 U1 0 U2 2 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 0889-2229 J9 AIDS RES HUM RETROV JI Aids Res. Hum. Retrovir. PD NOV 20 PY 2001 VL 17 IS 17 BP 1655 EP 1659 DI 10.1089/088922201753342068 PG 5 WC Immunology; Infectious Diseases; Virology SC Immunology; Infectious Diseases; Virology GA 503MD UT WOS:000172801500009 PM 11779353 ER PT J AU Bisson, SE Armstrong, KM Kulp, TJ Hartings, M AF Bisson, SE Armstrong, KM Kulp, TJ Hartings, M TI Broadly tunable, mode-hop-tuned cw optical parametric oscillator based on periodically poled lithium niobate SO APPLIED OPTICS LA English DT Article ID TRACE-GAS-DETECTION; CONTINUOUS-WAVE; FREQUENCY; LINBO3; SPECTROMETER; POWER AB We describe a broadly tunable, ew optical parametric oscillator (OPO) based on periodically poled lithium niobate. The OPO can be tuned over a broad region in the mid IR (2900-3100 cm(-1)) covering the important C-H stretch region while a high spectral resolution (<0.1 cm(-1)) is maintained. The OPO is the light source for a field-portable photoacoustic spectrometer for gas-phase monitoring of volatile organic compounds. (C) 2001 Optical Society of America. C1 Sandia Natl Labs, Livermore, CA 94550 USA. Northwestern Univ, Evanston, IL 60208 USA. RP Sandia Natl Labs, 7011 E Ave MS 9051, Livermore, CA 94550 USA. NR 16 TC 27 Z9 33 U1 0 U2 7 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD NOV 20 PY 2001 VL 40 IS 33 BP 6049 EP 6055 DI 10.1364/AO.40.006049 PG 7 WC Optics SC Optics GA 493UY UT WOS:000172242900010 PM 18364902 ER PT J AU Kirby, BJ Hanson, RK AF Kirby, BJ Hanson, RK TI CO2 imaging with saturated planar laser-induced vibrational fluorescence SO APPLIED OPTICS LA English DT Article ID TUNABLE-DIODE-LASER; Q-BRANCH; CARBON-DIOXIDE; ENERGY-TRANSFER; POLYATOMIC-MOLECULES; NITROUS-OXIDE; BANDS; MONOXIDE; SPECTRA; GASES AB We present new vibrational (infrared) planar laser-induced fluorescence (PLIF) imaging techniques for CO2 that use a simple, inexpensive, high-pulse-energy transversely excited atmospheric CO2 laser to saturate a CO2 absorption transition at 10.6 mum. Strong excitation by use of a CO2 laser provides increased signal levels at flame temperatures and simplifies image interpretation. Because rotational energy transfer and intramodal vibrational energy transfer are fast, vibrational distributions can be approximated by use of a simple three-temperature model. Imaging results from a 425 K unsteady transverse CO2 jet and a laminar coflowing CO/H-2 diffusion flame with temperatures near 1500 K are presented. If needed, temperature-insensitive signal levels can be generated with a two-laser technique. These results illustrate the potential for saturated infrared PLIF in a variety of flows. (C) 2001 Optical Society of America. C1 Stanford Univ, Dept Engn Mech, Stanford, CA 94309 USA. RP Sandia Natl Labs, Microfluid Dept, POB 969,Mail Stop 9951, Livermore, CA 94551 USA. EM bjkirby@sandia.gov NR 25 TC 12 Z9 13 U1 0 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD NOV 20 PY 2001 VL 40 IS 33 BP 6136 EP 6144 DI 10.1364/AO.40.006136 PG 9 WC Optics SC Optics GA 493UY UT WOS:000172242900021 PM 18364913 ER PT J AU Sokasian, A Gawiser, E Smoot, GF AF Sokasian, A Gawiser, E Smoot, GF TI Contribution of bright extragalactic radio sources to microwave anisotropy SO ASTROPHYSICAL JOURNAL LA English DT Article DE catalogs; cosmic microwave background; radio continuum : galaxies ID NRAO PMN SURVEYS; MILLIMETER CONTINUUM MEASUREMENTS; SOURCE CATALOG; BACKGROUND-RADIATION; PEAKED-SPECTRUM; COMPLETE SAMPLE; SKY MAPS; POLARIZATIONS; WAVELENGTHS; CENTIMETER AB We estimate the contribution of extragalactic radio sources to fluctuations in sky temperature over the range of frequencies (10-300 GHz) used for cosmic microwave background (CMB) anisotropy measurements. CMB anisotropy observations at high resolution and low frequencies are especially sensitive to this foreground. Our catalog of 2207 bright radio sources includes 758 sources with flux measurements at 90 GHz. We develop a method to extrapolate the source spectra and predict skymaps of extragalactic radio sources at instrument resolutions of 10'-10 degrees FWHM. Our results indicate that the brightest radio sources will dominate microwave anisotropy for a wide range of resolutions and frequencies. We predict the location and flux of the brightest radio sources at each frequency, making it straightforward to develop a template for masking the pixels containing them. This masking should be sufficient to protect most CMB anisotropy observations from unacceptable radio source confusion. C1 Harvard Univ, Dept Astron, Cambridge, MA 02138 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Sokasian, A (reprint author), Harvard Univ, Dept Astron, 60 Garden St, Cambridge, MA 02138 USA. NR 58 TC 20 Z9 20 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 2001 VL 562 IS 1 BP 88 EP 94 DI 10.1086/323500 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 499LH UT WOS:000172572300007 ER PT J AU Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Cook, KH Drake, AJ Freeman, KC Geha, M Griest, K Lehner, MJ Marshall, SL Minniti, D Nelson, CA Peterson, BA Popowski, P Pratt, MR Quinn, PJ Stubbs, CW Sutherland, W Vandehei, T Welch, DL AF Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Cook, KH Drake, AJ Freeman, KC Geha, M Griest, K Lehner, MJ Marshall, SL Minniti, D Nelson, CA Peterson, BA Popowski, P Pratt, MR Quinn, PJ Stubbs, CW Sutherland, W Vandehei, T Welch, DL CA MACHO Collaboration TI Astrometry with the MACHO data archive. I. High proper motion stars toward the Galactic bulge and Magellanic Clouds SO ASTROPHYSICAL JOURNAL LA English DT Article DE astrometry; catalogs; solar neighborhood; stars : kinematics; stars : low-mass, brown dwarfs ID DIFFERENCE IMAGE-ANALYSIS; DECLINATIONS BETWEEN-5-DEGREES AND-30-DEGREES; HUBBLE-DEEP-FIELD; RIGHT ASCENSIONS; 13H 30M; FAINT; HALO; PROJECT; CATALOG; OBJECTS AB We present the preliminary results of our astrometric study of stellar motions along the lines of sight of the Magellanic Clouds and the Galactic bulge. Using 5 years of MACHO project point-spread function photometry, we find that we can easily select stars with proper motions of 0."03 yr(-1) from these very dense fields, using the characteristic shapes of their light curves. By performing astrometry on photometrically selected, candidate, high proper motion (HPM) stars in 50 deg(2), we have discovered 154 new HPM stars from similar to 55 million stars monitored by the MACHO project. These new objects have proper motions as high as 0."5 yr(-1), brightnesses ranging from V similar to 13 to V similar to 19, and V - R colors between 0.3 and 1.45. C1 Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Australian Natl Univ, Canberra, ACT 0200, Australia. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Australian Natl Univ, Res Sch Astron & Astrophys, Weston, ACT 2611, Australia. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Pontificia Univ Catolica Chile, Dept Astron, Santiago 22, Chile. MIT, Ctr Space Res, Cambridge, MA 02139 USA. European So Observ, D-85748 Garching, Germany. Univ Washington, Dept Astron & Phys, Seattle, WA 98195 USA. Univ Oxford, Dept Phys, Oxford OX1 3RH, England. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. RP Alcock, C (reprint author), Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. RI Stubbs, Christopher/C-2829-2012; Quinn, Peter/B-3638-2013; OI Stubbs, Christopher/0000-0003-0347-1724; Lehner, Matthew/0000-0003-4077-0985 NR 39 TC 16 Z9 16 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 2001 VL 562 IS 1 BP 337 EP 347 DI 10.1086/323438 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 499LH UT WOS:000172572300024 ER PT J AU Mauche, CW Robinson, EL AF Mauche, CW Robinson, EL TI First simultaneous optical and extreme-ultraviolet observations of the quasi-coherent oscillations of SS Cygni SO ASTROPHYSICAL JOURNAL LA English DT Article DE novae, cataclysmic variables; stars : individual (SS Cygni); stars : oscillations; ultraviolet : stars ID UX URSAE MAJORIS; CATACLYSMIC VARIABLES; RAPID OSCILLATIONS; DWARF NOVAE; OUTBURST; LIGHT; FLUX AB Using extreme-ultraviolet (EUV) photometry obtained with the Extreme Ultraviolet Explorer (EUVE) satellite and UBVR optical photometry obtained with the 2.7 m telescope at McDonald Observatory, we have detected quasi-coherent oscillations (so-called dwarf nova oscillations) in the EUV and optical flux of the dwarf nova SS Cyg during its 1996 October outburst. There are two new results from these observations. First, we have for the first time observed "frequency doubling": during the rising branch of the outburst, the period of the EUV oscillation was observed to jump from 6.59 to 2.91 s. Second, we have for the first time observed quasi-coherent oscillations simultaneously in the optical and EUV. We find that the period and phase of the oscillations are the same in the two wave bands, finally confirming the long-held assumption that the periods of the optical and EUV/soft X-ray oscillations of dwarf novae are equal. The UBV oscillations can be simply the Rayleigh-Jeans tail of the EUV oscillations if the boundary layer temperature kT(bb) less than or similar to 15 eV and hence the luminosity L(bb) greater than or similar to 1.2 x 10(34)(d/75 pc)(2) ergs s(-1) (comparable to that of the accretion disk). Otherwise, the lack of a phase delay between the EUV and optical oscillations requires that the optical reprocessing site lies within the inner third of the accretion disk. This is strikingly different from other cataclysmic variables, where much or all of the disk contributes to the optical oscillations. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. RP Mauche, CW (reprint author), Lawrence Livermore Natl Lab, L-43,7000 East Ave, Livermore, CA 94550 USA. EM mauche@cygnus.llnl.gov; elr@astro.as.utexas.edu NR 28 TC 13 Z9 13 U1 0 U2 1 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 NOV 20 PY 2001 VL 562 IS 1 BP 508 EP 514 DI 10.1086/323870 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 499LH UT WOS:000172572300039 ER PT J AU van Dokkum, PG Stanford, SA AF van Dokkum, PG Stanford, SA TI A massive disk galaxy at z=1.34 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : evolution; galaxies : formation; galaxies : kinematics and dynamics; galaxies : spiral; galaxies : structure ID EXTRAGALACTIC DISTANCE SCALE; EVOLUTION AB We report on the discovery of a rapidly rotating disk in a K-selected galaxy at z = 1.34. Spatially resolved kinematics are determined from deep, moderate-resolution Keck spectroscopy covering the redshifted [O II] 3727 Angstrom line. A conservative estimate of the maximum rotation velocity V-max = 290 +/- 20 km s(-1), placing the galaxy among the most rapid rotators known. A Hubble Space Telescope Wide Field Planetary Camera 2 image taken in the I-F814W filter (rest-frame U) shows that the [O ii] emission originates in a ring of star-forming regions similar to3" (similar to 20 h(75)(-1) kpc) across. In the K band, the galaxy is compact, and its position coincides with the center of the star-forming ring seen in the rest-frame near-UV. The galaxy has M-v = 22.4 +/- 0.2 (similar to 3L(*)) in the rest frame, and its spectral energy distribution is very well fitted by that of a redshifted Sb/c galaxy. The observed kinematics, morphology, and spectral energy distribution are consistent with a massive bulge-disk system at z = 1.34. The lower limit on V-max gives an upper limit on the offset from the present-day Tully-Fisher relation. The galaxy is overluminous by less than mag in rest-frame V, consistent with previous studies of disk galaxies at lower redshift. Taken together, these results suggest that some of the most luminous spiral galaxies in the nearby universe were already in place similar to 10(10) yr ago, placing a constraint on models for their formation. C1 CALTECH, Dept Astron, Pasadena, CA 91125 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. RP van Dokkum, PG (reprint author), CALTECH, Dept Astron, MS 105-24, Pasadena, CA 91125 USA. NR 36 TC 24 Z9 24 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 2001 VL 562 IS 1 BP L35 EP L38 DI 10.1086/338192 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 499LJ UT WOS:000172572400008 ER PT J AU Wangard, W Dandy, DS Miller, BJ AF Wangard, W Dandy, DS Miller, BJ TI A numerically stable method for integration of the multicomponent species diffusion equations SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE multicomponent diffusion; mass transfer; stability; integration scheme ID ACCURATE AB A diagonally implicit method is shown to be an effective method for integrating the multicomponent species conservation equations. The constitutive equation for multicomponent diffusion is recast into a form analogous to that for binary diffusion. except that the diffusion coefficient is replaced with a matrix of effective multicomponent diffusion coefficients. The resulting matrix has properties that allow the diagonal terms to be integrated implicitly and the off-diagonal terms to be integrated explicitly. Numerical experiments show the integration procedure is stable for time steps much larger than the diffusion equation time step condition. (C) 2001 Elsevier Science. C1 Colorado State Univ, Dept Mech Engn, Ft Collins, CO 80523 USA. Colorado State Univ, Dept Chem Engn, Ft Collins, CO 80523 USA. Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Wangard, W (reprint author), Colorado State Univ, Dept Mech Engn, Ft Collins, CO 80523 USA. RI Dandy, David/G-6984-2012 OI Dandy, David/0000-0003-3254-0717 NR 21 TC 27 Z9 28 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 NOV 20 PY 2001 VL 174 IS 1 BP 460 EP 472 DI 10.1006/jcph.2001.6930 PG 13 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 499UG UT WOS:000172588300020 ER PT J AU Rider, WJ Margolin, LG AF Rider, WJ Margolin, LG TI Simple modifications of monotonicity-preserving limiters SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE limiters; sign preserving; bounds preserving ID CONSERVATIVE DIFFERENCE SCHEME; NONLINEAR RENORMALIZATION; ADVECTIVE FLUXES; SOLVER; LAWS; EQUATIONS; TRANSPORT AB We present simple modifications of standard monotonicity-preserving limiters that provide either sign preservation or alternative bounding values for the resulting numerical schemes (e.g., that the solution remain between zero and one rather than preserving monotonicity). These limiters can be easily implemented in Godunov-type methods by modifying the reconstruction step of the algorithm. These modifications allow methods to achieve greater formal accuracy, for example by improving the first-order accuracy in the L-infinity norm. The greatest advantage of our approach is its natural extension to more than one spatial dimension, and to systems of equations without operator splitting. C1 Los Alamos Natl Lab, Comp & Computat Sci Div, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Comp & Computat Sci Div, MS D413, Los Alamos, NM 87545 USA. EM wjr@lanl.gov; len@lanl.gov NR 24 TC 16 Z9 17 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD NOV 20 PY 2001 VL 174 IS 1 BP 473 EP 488 DI 10.1006/jcph.2001.6914 PG 16 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 499UG UT WOS:000172588300021 ER PT J AU Liu, SF Schmidt-Rohr, K AF Liu, SF Schmidt-Rohr, K TI High-resolution solid-state C-13 NMR of fluoropolymers SO MACROMOLECULES LA English DT Article ID NUCLEAR MAGNETIC-RESONANCE; FLUOROCARBON POLYMERS; CRYSTALLINE; ANGLE C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. EM srohr@iastate.edu NR 18 TC 45 Z9 45 U1 0 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 EI 1520-5835 J9 MACROMOLECULES JI Macromolecules PD NOV 20 PY 2001 VL 34 IS 24 BP 8416 EP 8418 DI 10.1021/ma0113576 PG 3 WC Polymer Science SC Polymer Science GA 493YE UT WOS:000172250400005 ER PT J AU Nieto, MM AF Nieto, MM TI Coherent states for unusual potentials SO MODERN PHYSICS LETTERS A LA English DT Article DE quantum mechanics; supersymmetry; coherence ID GENERAL POTENTIALS; EXTRA DIMENSIONS; GRAVITY; SUPERSYMMETRY AB The program to construct minimum-uncertainty coherent states for general potentials works transparently with solvable analytic potentials. However, when an analytic potential is not completely solvable, like for a double-well or the linear (gravitational) potential, there can be a conundrum. Motivated by supersymmetry concepts in higher dimensions, we show how these conundrums can be overcome. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Nieto, MM (reprint author), Los Alamos Natl Lab, Div Theoret, MS-B285, Los Alamos, NM 87545 USA. NR 24 TC 12 Z9 12 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-7323 J9 MOD PHYS LETT A JI Mod. Phys. Lett. A PD NOV 20 PY 2001 VL 16 IS 35 BP 2305 EP 2311 PG 7 WC Physics, Nuclear; Physics, Particles & Fields; Physics, Mathematical SC Physics GA 512CD UT WOS:000173302800006 ER PT J AU Muhlstein, CL Brown, SB Ritchie, RO AF Muhlstein, CL Brown, SB Ritchie, RO TI High-cycle fatigue and durability of polycrystalline silicon thin films in ambient air SO SENSORS AND ACTUATORS A-PHYSICAL LA English DT Article DE fatigue; stress-life; durability; silicon; polysilicon; MEMS ID SUBCRITICAL CRACK-GROWTH; SINGLE-CRYSTAL; POLYSILICON; TOUGHNESS; CERAMICS AB To evaluate the long-term durability proper-ties of materials for microelectromechanical systems (MEMS), the stress-life (SIN) cyclic fatigue behavior of a 2-mum thick polycrystalline silicon film was evaluated in laboratory air using an electrostatically actuated notched cantilever beam resonator. A total of 28 specimens were tested for failure under high frequency (similar to 40 kHz) cyclic loads with lives ranging from about 10 s to 34 days (3 x 10(5) to 1.2 x 10(11) cycles) over fully reversed, sinusoidal stress amplitudes varying from similar to2.0 to 4.0 GPa. The thin-film polycrystalline silicon cantilever beams exhibited a time-delayed failure that was accompanied by a continuous increase in the compliance of the specimen. This apparent cyclic fatigue effect resulted in an endurance strength, at greater than 10(9) cycles, of similar to2 GPa, i.e. roughly one-half of the (single cycle) fracture strength. Based on experimental and numerical results, the fatigue process is attributed to a novel mechanism involving the environmentally-assisted cracking of the surface oxide film (termed reaction-layer fatigue). These results provide the most comprehensive, high-cycle, endurance data for designers of polysilicon micromechanical components available to date. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, LBNL, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Exponent Inc, Natick, MA 01760 USA. RP Muhlstein, CL (reprint author), Univ Calif Berkeley, LBNL, Dept Mat Sci & Engn, 1 Cyclotron Rd,MS 62-203, Berkeley, CA 94720 USA. EM cmuhlstn@uclinkr.berkeley RI Ritchie, Robert/A-8066-2008; OI Ritchie, Robert/0000-0002-0501-6998; Muhlstein, Christopher/0000-0002-5928-068X NR 29 TC 107 Z9 114 U1 2 U2 19 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0924-4247 J9 SENSOR ACTUAT A-PHYS JI Sens. Actuator A-Phys. PD NOV 20 PY 2001 VL 94 IS 3 BP 177 EP 188 DI 10.1016/S0924-4247(01)00709-9 PG 12 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 490RW UT WOS:000172065700007 ER PT J AU Chambers, SA Thevuthasan, S Farrow, RFC Marks, RF Thiele, JU Folks, L Samant, MG Kellock, AJ Ruzycki, N Ederer, DL Diebold, U AF Chambers, SA Thevuthasan, S Farrow, RFC Marks, RF Thiele, JU Folks, L Samant, MG Kellock, AJ Ruzycki, N Ederer, DL Diebold, U TI Epitaxial growth and properties of ferromagnetic co-doped TiO2 anatase SO APPLIED PHYSICS LETTERS LA English DT Article ID INJECTION AB We have used oxygen-plasma-assisted molecular-beam epitaxy (OPA-MBE) to grow CoxTi1-xO2 anatase on SrTiO3(001) for x=similar to0.01-0.10, and have measured the structural, compositional, and magnetic properties of the resulting films. Whether epitaxial or polycrystalline, these CoxTi1-xO2 films are ferromagnetic semiconductors at and above room temperature. However, the magnetic and structural properties depend critically on the Co distribution, which varies widely with growth conditions. Co is substitutional in the anatase lattice and in the +2 formal oxidation state in ferromagnetic CoxTi1-xO2. The magnetic properties of OPA-MBE grown material are significantly better than those of analogous pulsed laser deposition-grown material. (C) 2001 American Institute of Physics. C1 Pacific NW Natl Lab, Fundamental Sci Div, Richland, WA 99352 USA. IBM Corp, Almaden Res Ctr, San Jose, CA USA. Tulane Univ, Dept Phys, New Orleans, LA 70118 USA. RP Chambers, SA (reprint author), Pacific NW Natl Lab, Fundamental Sci Div, Richland, WA 99352 USA. RI Diebold, Ulrike/A-3681-2010; Folks, Liesl/C-7611-2016 OI Diebold, Ulrike/0000-0003-0319-5256; Folks, Liesl/0000-0003-0161-957X NR 10 TC 345 Z9 358 U1 6 U2 63 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 19 PY 2001 VL 79 IS 21 BP 3467 EP 3469 DI 10.1063/1.1420434 PG 3 WC Physics, Applied SC Physics GA 493CK UT WOS:000172204300029 ER PT J AU Bu, SD Lee, MK Eom, CB Tian, W Pan, XQ Streiffer, SK Krajewski, JJ AF Bu, SD Lee, MK Eom, CB Tian, W Pan, XQ Streiffer, SK Krajewski, JJ TI Perovskite phase stabilization in epitaxial Pb(Mg1/3Nb2/3)O-3-PbTiO3 films by deposition onto vicinal (001) SrTiO3 substrates SO APPLIED PHYSICS LETTERS LA English DT Article ID SRRUO3 THIN-FILMS; CHEMICAL-VAPOR-DEPOSITION; LEAD MAGNESIUM NIOBATE; PIEZOELECTRIC BEHAVIOR; DOMAIN-STRUCTURE; (001)SRTIO3; GROWTH; HETEROSTRUCTURES; MICROSTRUCTURE; FABRICATION AB We report the perovskite phase stabilization of 0.67Pb(Mg1/3Nb2/3)O-3-0.33PbTiO(3) (PMN-PT) epitaxial thin films by deposition onto miscut substrates. Films were grown on (001) SrTiO3 substrates with miscut angles from 0 to 8 degrees toward the [100] direction using 90 degrees off-axis magnetron sputtering. Films on high miscut substrates (>4 degrees) showed almost the pure perovskite phase in both x-ray diffraction and transmission electron microscopy image, and were nearly stoichiometric. In contrast, films on exact (001) SrTiO3 contained a high volume fraction of pyrochlore phases with Pb deficiency. Atomic force microscopy reveals that films on 8 degrees miscut substrates have a much smoother surface morphology than those on exact (001) SrTiO3. Cross-sectional transmission electron microscopy images reveal that the pyrochlore phases nucleate on top of the perovskite phase, and that the amount of the pyrochlore phases increase with film thickness. A film on an 8 degrees miscut substrate exhibits a polarization hysteresis loop with a remnent polarization of 20 muC/cm(2) at room temperature. (C) 2001 American Institute of Physics. C1 Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Bell Lab, Lucent Technol, Murray Hill, NJ 07974 USA. RP Bu, SD (reprint author), Univ Wisconsin, Dept Mat Sci & Engn, Madison, WI 53706 USA. RI Bu, Sang Don/B-1576-2008; Streiffer, Stephen/A-1756-2009; Eom, Chang-Beom/I-5567-2014 OI Bu, Sang Don/0000-0003-4883-1308; NR 19 TC 54 Z9 54 U1 5 U2 31 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 19 PY 2001 VL 79 IS 21 BP 3482 EP 3484 DI 10.1063/1.1414293 PG 3 WC Physics, Applied SC Physics GA 493CK UT WOS:000172204300034 ER PT J AU Guillorn, MA Melechko, AV Merkulov, VI Ellis, ED Britton, CL Simpson, ML Lowndes, DH Baylor, LR AF Guillorn, MA Melechko, AV Merkulov, VI Ellis, ED Britton, CL Simpson, ML Lowndes, DH Baylor, LR TI Operation of a gated field emitter using an individual carbon nanofiber cathode SO APPLIED PHYSICS LETTERS LA English DT Article ID EMISSION; NANOTUBES AB We report on the operation of an integrated gated cathode device using a single vertically aligned carbon nanofiber as the field emission element. This device is capable of operation in a moderate vacuum for extended periods of time without experiencing a degradation of performance. Less than 1% of the total emitted current is collected by the gate electrode, indicating that the emitted electron beam is highly collimated. As a consequence, this device is ideal for applications that require well-focused electron emission from a microscale structure. C1 Oak Ridge Natl Lab, Mol Scale Engn & Nanoscale Technol Res Grp, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37831 USA. RP Guillorn, MA (reprint author), Oak Ridge Natl Lab, Mol Scale Engn & Nanoscale Technol Res Grp, Oak Ridge, TN 37831 USA. RI Melechko, Anatoli/B-8820-2008; Simpson, Michael/A-8410-2011; OI Simpson, Michael/0000-0002-3933-3457; Baylor, Larry/0000-0002-0325-7771 NR 14 TC 85 Z9 88 U1 2 U2 15 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 19 PY 2001 VL 79 IS 21 BP 3506 EP 3508 DI 10.1063/1.1419038 PG 3 WC Physics, Applied SC Physics GA 493CK UT WOS:000172204300042 ER PT J AU Niu, S Hall, NB AF Niu, S Hall, NB TI Modeling the active sites in metalloenzymes 5. The heterolytic bond cleavage of H-2 in the [NiFe] hydrogenase of Desulfovibrio gigas by a nucleophilic addition mechanism SO INORGANIC CHEMISTRY LA English DT Article ID NICKEL-IRON HYDROGENASE; DENSITY-FUNCTIONAL THEORY; CATALYTIC PROPERTIES; CHROMATIUM-VINOSUM; FE HYDROGENASES; BASIS-SETS; ACTIVATION; EXCHANGE; CRYSTAL; HYDROGENASE AB The H-2 activation catalyzed by an Fe(II)-Ni(III) model of the [NiFe] hydrogenase of Desulfovibrio gigas has been investigated by density functional theory (DFT/B3LYP) calculations on the neutral and anionic active site complexes, [(CO)(CN)(2)Fe(mu -SH)(2)Ni(SH)(SH2)](0) and [(CO)(CN)(2)Fe(mu -SH)(2)Ni(SH)(2)](-). The results suggest that the reaction proceeds by a nucleophilic addition mechanism that cleaves the H-H bond heterolytically. The terminal cysteine residue Cys530 in the [NiFe] hydrogenase active site of the D. gigas enzyme plays a crucial role in the catalytic process by accepting the proton. The active site is constructed to provide access by this cysteine residue, and this role explains the change in activity observed when this cysteine is replaced by a selenocysteine. Furthermore, the optimized geometry of the transition state in the model bears a striking resemblance to the geometry of the active site as determined by X-ray crystallography. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, HPCC Grp, Richland, WA 99352 USA. Texas A&M Univ, Dept Chem, College Stn, TX 77843 USA. RP Niu, S (reprint author), Washington State Univ, Sch Mol Biosci, Pullman, WA 99164 USA. NR 57 TC 43 Z9 43 U1 0 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD NOV 19 PY 2001 VL 40 IS 24 BP 6201 EP 6203 DI 10.1021/ic0107274 PG 3 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 492RM UT WOS:000172181400018 PM 11703120 ER PT J AU Boyle, TJ Alam, TM Peters, KP Rodriguez, MA AF Boyle, TJ Alam, TM Peters, KP Rodriguez, MA TI Structural diversity of lithium neopentoxide compounds SO INORGANIC CHEMISTRY LA English DT Article ID X-RAY STRUCTURES; TITANIUM(IV) NEOPENTOXIDES; ALKOXIDES; COORDINATION; GLASSES AB The reaction of LiN(SiMe3)(2) with 1 equiv of HOCH2CMe3 (HONep) in toluene led to the formation of [Li(mu (3)-ONep)](8) (1). The complex adopts a novel dual-edge fused hexagon-square prismatic structure with a C-2 nu axis of rotation that relates the top and bottom eight-membered rings. Substituting the noncoordinating solvent toluene for a Lewis basic solvent (THF or py) led to the isolation of compounds of the general formula [Li(mu (3)-ONep)](4)-(solv)(3), where solv = THF (2) or py (3). The cube structures of 2 and 3 have one Li which is not solvated because of steric crowding of the ONep ligands. Multinuclear solid-state (Li-6, Li-7, and C-13) MAS and solution-state (H-1, Li-7, and C-13) NMR studies were undertaken to verify the identity of the bulk powder and to determine the solution behavior of these compounds. C1 Sandia Natl Labs, Adv Mat Lab, Albuquerque, NM 87105 USA. RP Boyle, TJ (reprint author), Sandia Natl Labs, Adv Mat Lab, 1001 Univ Blvd SE, Albuquerque, NM 87105 USA. NR 21 TC 23 Z9 23 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD NOV 19 PY 2001 VL 40 IS 24 BP 6281 EP 6286 DI 10.1021/ic0106569 PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 492RM UT WOS:000172181400029 PM 11703131 ER PT J AU Beane, SR Savage, MJ AF Beane, SR Savage, MJ TI Rearranging pionless effective field theory SO NUCLEAR PHYSICS A LA English DT Article ID DEUTERON COMPTON-SCATTERING; BIG-BANG NUCLEOSYNTHESIS; PROTON-PROTON FUSION; -> D-GAMMA; ELECTROMAGNETIC POLARIZABILITIES; LEADING ORDER; EXPANSION; PIONS AB We point out a redundancy in the operator structure of the pionless effective field theory, EFT(pi), which dramatically simplifies computations. This redundancy is best exploited by using dibaryon fields as fundamental degrees of freedom. In turn, this suggests a new power counting scheme which sums range corrections to all orders. We explore this method with a few simple observables: the deuteron charge form factor, np --> d gamma, and Compton scattering from the deuteron. Unlike EFT(pi), the higher-dimension operators involving electroweak gauge fields are not renormalized by the s-wave strong interactions, and therefore do not scale with inverse powers of the renormalization scale. Thus, naive dimensional analysis of these operators is sufficient to estimate their contribution to a given process. (C) 2001 Published by Elsevier Science B.V. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Beane, SR (reprint author), Univ Washington, Dept Phys, Seattle, WA 98195 USA. NR 39 TC 90 Z9 90 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 NOV 19 PY 2001 VL 694 IS 3-4 BP 511 EP 524 DI 10.1016/S0375-9474(01)01088-0 PG 14 WC Physics, Nuclear SC Physics GA 484GD UT WOS:000171681100006 ER PT J AU Del Duca, V Kilgore, W Oleari, C Schmidt, C Zeppenfeld, D AF Del Duca, V Kilgore, W Oleari, C Schmidt, C Zeppenfeld, D TI Gluon-fusion contributions to H+2 jet production SO NUCLEAR PHYSICS B LA English DT Article ID HIGGS-BOSON PRODUCTION; ONE-LOOP INTEGRALS; CERN LHC; COLLIDERS AB Real emission corrections to Higgs production via gluon-fusion, at order alpha (4)(S), lead to a Higgs plus two-jet final state. We present the calculation of these scattering amplitudes, as induced by top-quark triangle-, box- and pentagon-loop diagrams. These diagrams are evaluated analytically for arbitrary top mass int. We study the renormalization and factorization scale-dependence of the resulting H + 2 jet cross section, and discuss phenomenologically important distributions at the LHC. The gluon fusion results are compared to expectations for weak-boson fusion cross sections. (C) 2001 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 Wisconsin, Dept Phys, Madison, WI 53706 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. RP Del Duca, V (reprint author), Ist Nazl Fis Nucl, Sez Torino, Via P Giuria 1, I-10125 Turin, Italy. EM oleari@pheno.physics.wisc.edu RI del duca, vittorio/F-6992-2012 NR 30 TC 126 Z9 126 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 NOV 19 PY 2001 VL 616 IS 1-2 BP 367 EP 399 DI 10.1016/S0550-3213(01)00446-1 PG 33 WC Physics, Particles & Fields SC Physics GA 491EW UT WOS:000172095900013 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Artikov, A Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van Brink, S Bromberg, C Brozovic, M Brubaker, E Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Cabrera, S Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Castro, A Cauz, D Cerri, A Chan, AW 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 Chung, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Dominguez, A Donati, S Done, J D'Onofrio, M Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallas, A Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G de Costa, JG Haas, RM Haber, C Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E 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 Kilminster, B Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kondo, K Konigsberg, J Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lath, A Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Litvintsev, DO Lobban, O Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nagaslaev, V Nahn, S Nakada, H Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Oh, YD Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Rakitine, A Ratnikov, F Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Ruiz, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C 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 Sidoti, A Siegrist, J 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 Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Tonelli, D Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Veramendi, G Vidal, R Vila, I Vilar, R Volobouev, I von der Mey, M Vucinic, D Wagner, RG Wagner, RL Wallace, NB Wan, Z Wang, C Wang, MJ Ward, B Waschke, S Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkes, T Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Wu, X Wyss, J Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S AF Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Artikov, A Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van Brink, S Bromberg, C Brozovic, M Brubaker, E Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Cabrera, S Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Castro, A Cauz, D Cerri, A Chan, AW 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 Chung, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Dominguez, A Donati, S Done, J D'Onofrio, M Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallas, A Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G de Costa, JG Haas, RM Haber, C Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E 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 Kilminster, B Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kondo, K Konigsberg, J Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lath, A Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Litvintsev, DO Lobban, O Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nagaslaev, V Nahn, S Nakada, H Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Oh, YD Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Rakitine, A Ratnikov, F Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Ruiz, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C 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 Sidoti, A Siegrist, J 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 Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Tonelli, D Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Veramendi, G Vidal, R Vila, I Vilar, R Volobouev, I von der Mey, M Vucinic, D Wagner, RG Wagner, RL Wallace, NB Wan, Z Wang, C Wang, MJ Ward, B Waschke, S Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkes, T Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Wu, X Wyss, J Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Charged-particle multiplicity p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID QCD ANALYTIC PREDICTIONS; E+E ANNIHILATION; QUARK JETS; GLUON JETS; HADRON MULTIPLICITY; 3-JET EVENTS; DISTRIBUTIONS; SPECTRA; FRAGMENTATION; DEPENDENCE AB We report on a measurement of the mean charged-particle multiplicity of jets in dijet events with dijet masses in the range 80-630 GeV/c(2), produced at the Tevatron in p(p) over bar collisions with roots = 1.8 TeV and recorded by the Collider Detector at Fermilab. The data are fit to perturbative-QCD calculations carried out in the framework of the modified leading log approximation and the hypothesis of local parton-hadron duality. The fit yields values for two parameters in that framework: the ratio of parton multiplicities in gluon and quark jets, r = N-partons(g-jet)/N-partons(q-jet) = 1.7 +/- 0.3, and the ratio of the number of charged hadrons to the number of partons in a jet, K-LPHD(charged) = N-hadrons(charged)/N-partons = 0.57 +/- C1 Ernest Orlando Lawrence 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 Davis, Davis, CA 95616 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Cantabria, CSIC, Inst Fis Cantabria, E-39005 Santander, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Nucl Res Inst, RU-141980 Dubna, Russia. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. 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, Ctr High Energy Phys, Taegu 702701, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Sungkyunkwan Univ, Suwon 440746, South Korea. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Oxford, Oxford OX1 3RH, England. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Toronto, Inst Particle Phys, Toronto, ON M5S 1A7, Canada. 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 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Ruiz, Alberto/E-4473-2011; St.Denis, Richard/C-8997-2012; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Kim, Soo-Bong/B-7061-2014; Gallas Torreira, Abraham Antonio/K-6508-2014; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; Cabrera Urban, Susana/H-1376-2015; Prokoshin, Fedor/E-2795-2012; Introzzi, Gianluca/K-2497-2015; Gorelov, Igor/J-9010-2015 OI Ruiz, Alberto/0000-0002-3639-0368; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Gallas Torreira, Abraham Antonio/0000-0002-2745-7954; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Prokoshin, Fedor/0000-0001-6389-5399; Introzzi, Gianluca/0000-0002-1314-2580; Gorelov, Igor/0000-0001-5570-0133 NR 39 TC 16 Z9 16 U1 1 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 19 PY 2001 VL 87 IS 21 AR 211804 DI 10.1103/PhysRevLett.87.211804 PG 6 WC Physics, Multidisciplinary SC Physics GA 496NA UT WOS:000172400600011 PM 11736333 ER PT J AU Butov, LV Lai, CW Chemla, DS Lozovik, YE Campman, KL Gossard, AC AF Butov, LV Lai, CW Chemla, DS Lozovik, YE Campman, KL Gossard, AC TI Observation of magnetically induced effective-mass enhancement of quasi-2D excitons SO PHYSICAL REVIEW LETTERS LA English DT Article ID COUPLED QUANTUM-WELLS; COLLECTIVE EXCITATIONS; LANDAU-LEVEL; ELECTRON; DENSITY; FIELD; STATE; GAP AB We present the first measurements of the dispersion relation of a quasi-2D magnetoexciton. We demonstrate that the magnetoexciton effective mass is determined by the coupling between the center-of-mass motion and internal structure and becomes overwhelmingly larger than the sum of the electron and hole masses in high magnetic fields. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Russian Acad Sci, Inst Spect, Troitsk 142092, Russia. Univ Calif Santa Barbara, Dept Elect & Comp Engn, Santa Barbara, CA 93106 USA. RP Butov, LV (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Lai, Chih Wei/E-4945-2010 OI Lai, Chih Wei/0000-0003-3571-4671 NR 27 TC 55 Z9 56 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 NOV 19 PY 2001 VL 87 IS 21 AR 216804 DI 10.1103/PhysRevLett.87.216804 PG 4 WC Physics, Multidisciplinary SC Physics GA 496NA UT WOS:000172400600042 PM 11736364 ER PT J AU Fornal, B Broda, R Maier, KH Wrzesinski, J Lane, GJ Cromaz, M Macchiavelli, AO Clark, RM Vetter, K Byrne, AP Dracoulis, GD Carpenter, MP Janssens, RVF Wiedenhoever, I Rejmund, M Blomqvist, J AF Fornal, B Broda, R Maier, KH Wrzesinski, J Lane, GJ Cromaz, M Macchiavelli, AO Clark, RM Vetter, K Byrne, AP Dracoulis, GD Carpenter, MP Janssens, RVF Wiedenhoever, I Rejmund, M Blomqvist, J TI Effective charge of the pi h(11/12) orbital and the electric field gradient of Hg from the yrast structure of Hg-206 SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-SPIN STATES; PB-208; SPECTROSCOPY; NUCLEI AB The gamma -ray decay of excited states of the two-proton hole nucleus, Hg-206, has been identified using Gammasphere and Pb-208 + U-238 collisions. The yrast states found include a T-1/2 = 92(8) ns 10(+) isomer located above the known 5(-) isomer. The B(E2; 10(+) --> 8(+)) strength is used to derive the quadrupole polarization charge induced by the h(11/2) proton hole. Also, the implied quadrupole moment has been used to provide an absolute scale for the electric field gradient of Hg in Hg metal. C1 H Niewodniczanski Inst Nucl Phys, PL-31342 Krakow, Poland. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Australian Natl Univ, Dept Phys Nucl, Canberra, ACT 0200, Australia. Australian Natl Univ, Dept Phys, Canberra, ACT 0200, Australia. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. CEA Saclay, DAPNIA SPhN, F-91191 Gif Sur Yvette, France. Royal Inst Technol, Dept Phys Frescati, S-10405 Stockholm, Sweden. RP Fornal, B (reprint author), H Niewodniczanski Inst Nucl Phys, PL-31342 Krakow, Poland. RI Dracoulis, George/A-8123-2008; Lane, Gregory/A-7570-2011; Carpenter, Michael/E-4287-2015 OI Lane, Gregory/0000-0003-2244-182X; Carpenter, Michael/0000-0002-3237-5734 NR 26 TC 38 Z9 38 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 NOV 19 PY 2001 VL 87 IS 21 AR 212501 DI 10.1103/PhysRevLett.87.212501 PG 4 WC Physics, Multidisciplinary SC Physics GA 496NA UT WOS:000172400600013 PM 11736335 ER PT J AU Kim, P Shi, L Majumdar, A McEuen, PL AF Kim, P Shi, L Majumdar, A McEuen, PL TI Thermal transport measurements of individual multiwalled nanotubes SO PHYSICAL REVIEW LETTERS LA English DT Article ID WALLED CARBON NANOTUBES; THERMOELECTRIC-POWER; CONDUCTIVITY; QUANTUM; HEAT AB The thermal conductivity and thermoelectric power of a single carbon nanotube were measured using a microfabricated suspended device. The observed thermal conductivity is more than 3000 W/K m at room temperature, which is 2 orders of magnitude higher than the estimation from previous experiments that used macroscopic mat samples. The temperature dependence of the thermal conductivity of nanotubes exhibits a peak at 320 K due to the onset of umklapp phonon scattering. The measured thermoelectric power shows linear temperature dependence with a value of 80 muV/K at room temperature. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Kim, P (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Shi, Li/C-8123-2013; Kim, Philip/N-1886-2013 OI Shi, Li/0000-0002-5401-6839; NR 23 TC 1750 Z9 1801 U1 48 U2 417 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 NOV 19 PY 2001 VL 87 IS 21 AR 215502 DI 10.1103/PhysRevLett.87.215502 PG 4 WC Physics, Multidisciplinary SC Physics GA 496NA UT WOS:000172400600026 PM 11736348 ER PT J AU Leksanov, A Alster, J Asryan, G Averichev, Y Barton, D Baturin, V Bukhtoyarova, N Carroll, A Heppelmann, S Kawabata, T Makdisi, Y Malki, A Minina, E Navon, I Nicholson, H Ogawa, A Panebratsev, Y Piasetzky, E Schetkovsky, A Shimanskiy, S Tang, A Watson, JW Yoshida, H Zhalov, D AF Leksanov, A Alster, J Asryan, G Averichev, Y Barton, D Baturin, V Bukhtoyarova, N Carroll, A Heppelmann, S Kawabata, T Makdisi, Y Malki, A Minina, E Navon, I Nicholson, H Ogawa, A Panebratsev, Y Piasetzky, E Schetkovsky, A Shimanskiy, S Tang, A Watson, JW Yoshida, H Zhalov, D TI Energy dependence of nuclear transparency in C(p,2p) scattering SO PHYSICAL REVIEW LETTERS LA English DT Article ID COLOR TRANSPARENCY; ELASTIC-SCATTERING AB The transparency of carbon for (p, 2p) quasielastic events was measured at beam momenta ranging from 5.9 to 14.5 GeV/c at 90 degrees c.m. The four-momentum transfer squared (Q(2)) ranged from 4.7 to 12.7 (GeV/c)(2). We present the observed beam momentum dependence of the ratio of the carbon to hydrogen cross sections. We also apply a model for the nuclear momentum distribution of carbon to obtain the nuclear transparency. We find a sharp rise in transparency as the beam momentum is increased to 9 GcV/c and a reduction to approximately the Glauber level at higher energies. C1 Penn State Univ, Dept Phys, University Pk, PA 16801 USA. Tel Aviv Univ, Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Yerevan Phys Inst, Yerevan 375036, Armenia. Brookhaven Natl Lab, Collider Accelerator Dept, Upton, NY 11973 USA. Petersburg Nucl Phys Inst, St Petersburg 188350, Russia. Kyoto Univ, Dept Phys, Sakyo Ku, Kyoto 6068502, Japan. Mt Holyoke Coll, Dept Phys, S Hadley, MA 01075 USA. Joint Inst Nucl Res, Dubna 141980, Russia. Kent State Univ, Dept Phys, Kent, OH 44242 USA. RP Leksanov, A (reprint author), Penn State Univ, Dept Phys, University Pk, PA 16801 USA. NR 16 TC 37 Z9 37 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 NOV 19 PY 2001 VL 87 IS 21 AR 212301 DI 10.1103/PhysRevLett.87.212301 PG 4 WC Physics, Multidisciplinary SC Physics GA 496NA UT WOS:000172400600012 PM 11736334 ER PT J AU Takahashi, H Ahn, JK Akikawa, H Aoki, S Arai, K Bahk, SY Baik, KM Bassalleck, B Chung, JH Chung, MS Davis, DH Fukuda, T Hoshino, K Ichikawa, A Ieiri, M Imai, K Iwata, YH Iwata, YS Kanda, H Kaneko, M Kawai, T Kawasaki, M Kim, CO Kim, JY Kim, SJ Kim, SH Kondo, Y Kouketsu, T Lee, YL McNabb, JWC Mitsuhara, M Nagase, Y Nagoshi, C Nakazawa, K Noumi, H Ogawa, S Okabe, H Oyama, K Park, HM Park, IG Parker, J Ra, YS Rhee, JT Rusek, A Shibuya, H Sim, KS Saha, PK Seki, D Sekimoto, M Song, JS Takahashi, T Takeutchi, F Tanaka, H Tanida, K Tojo, J Torii, H Torikai, S Tovee, DN Ushida, N Yamamoto, K Yasuda, N Yang, JT Yoon, CJ Yoon, CS Yosoi, M Yoshida, T Zhu, L AF Takahashi, H Ahn, JK Akikawa, H Aoki, S Arai, K Bahk, SY Baik, KM Bassalleck, B Chung, JH Chung, MS Davis, DH Fukuda, T Hoshino, K Ichikawa, A Ieiri, M Imai, K Iwata, YH Iwata, YS Kanda, H Kaneko, M Kawai, T Kawasaki, M Kim, CO Kim, JY Kim, SJ Kim, SH Kondo, Y Kouketsu, T Lee, YL McNabb, JWC Mitsuhara, M Nagase, Y Nagoshi, C Nakazawa, K Noumi, H Ogawa, S Okabe, H Oyama, K Park, HM Park, IG Parker, J Ra, YS Rhee, JT Rusek, A Shibuya, H Sim, KS Saha, PK Seki, D Sekimoto, M Song, JS Takahashi, T Takeutchi, F Tanaka, H Tanida, K Tojo, J Torii, H Torikai, S Tovee, DN Ushida, N Yamamoto, K Yasuda, N Yang, JT Yoon, CJ Yoon, CS Yosoi, M Yoshida, T Zhu, L TI Observation of a He-6(Lambda Lambda) double hypernucleus SO PHYSICAL REVIEW LETTERS LA English DT Article ID LAMBDA-LAMBDA-HYPERNUCLEI; H-DIBARYON; DOUBLE HYPERFRAGMENT; BINDING-ENERGIES; SEARCH; PARTICLE; CAPTURE AB A double-hyperfragment event has been found in a hybrid-emulsion experiment. It is identified uniquely as the sequential decay of He-6(Lambda Lambda) emitted from a Xi (-) hyperon nuclear capture at rest. ne mass of He-6(Lambda Lambda) and the Lambda-Lambda interaction energy DeltaB(Lambda Lambda) have been measured for the first time devoid of the ambiguities due to the possibilities of excited states. The value of DeltaB(Lambda Lambda) is 1-01 0.20(-0.11)(+0.18) mev. This demonstrates that the Lambda-Lambda interaction is weakly attractive. C1 Kyoto Univ, Dept Phys, Kyoto 6068502, Japan. Kobe Univ, Fac Human Dev, Kobe, Hyogo 6578501, Japan. Toho Univ, Dept Phys, Funabashi, Chiba 2748510, Japan. Korea Univ, Dept Phys, Seoul 136701, South Korea. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. Gifu Univ, Dept Phys, Gifu 5011193, Japan. UCL, Dept Phys & Astron, London WC1E 6BT, England. KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki 3050801, Japan. Nagoya Univ, Dept Phys, Nagoya, Aichi 4648601, Japan. Chonnam Natl Univ, Kwangju 500757, South Korea. Konkuk Univ, Inst Adv Phys, Seoul 143701, South Korea. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Higashi Nippon Int Univ, Iwaki, Fukushima 9708023, Japan. Osaka Prefectural Educ Ctr, Osaka 5580011, Japan. Brookhaven Natl Lab, Upton, NY 11973 USA. Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. Kyoto Sangyo Univ, Fac Sci, Kyoto 6038555, Japan. Aichi Univ Educ, Kariya, Aichi 4488542, Japan. Univ Tokyo, Dept Phys, Tokyo 1130033, Japan. Natl Inst Radiol Sci, Chiba 2638555, Japan. Osaka City Univ, Dept Phys, Osaka 5588585, Japan. RP Takahashi, H (reprint author), Kyoto Univ, Dept Phys, Kyoto 6068502, Japan. EM thitoshi@nh.scphys.kyoto-u.ac.jp RI Ahn, Jung Keun/C-1293-2008; Aoki, Shigeki/L-6044-2015 NR 28 TC 343 Z9 349 U1 1 U2 12 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 NOV 19 PY 2001 VL 87 IS 21 AR 212502 DI 10.1103/PhysRevLett.87.212502 PG 5 WC Physics, Multidisciplinary SC Physics GA 496NA UT WOS:000172400600014 PM 11736336 ER PT J AU Tracy, ER Kaufman, AN Jaun, A AF Tracy, ER Kaufman, AN Jaun, A TI A ray-based algorithm for multi-dimensional linear conversion SO PHYSICS LETTERS A LA English DT Article AB A numerical algorithm is proposed for connecting the incoming and outgoing wave fields in studies of linear conversion. This is the first such ray-based algorithm for wave conversion in multiple spatial dimensions. It is demonstrated that, aside from the overall phase of the coupling, one can directly evaluate all quantities needed for the connection coefficients from the ray geometry. The ray dynamics is generated using the determinant of the dispersion matrix as the Hamiltonian. Using information available while following an incoming ray, the algorithm automatically detects that the ray has entered a conversion region, evaluates the transmission and conversion coefficients, and launches the transmitted ray. The algorithm does not require any prior knowledge of the geometry of the conversion region. The algorithm is illustrated using a two-dimensional toroidal model with resonant conversion from a magnetosonic to an ion-hybrid wave. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Royal Inst Technol, Alfven Lab, SE-10044 Stockholm, Sweden. RP Tracy, ER (reprint author), Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. NR 0 TC 8 Z9 8 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 NOV 19 PY 2001 VL 290 IS 5-6 BP 309 EP 316 DI 10.1016/S0375-9601(01)00683-1 PG 8 WC Physics, Multidisciplinary SC Physics GA 495VA UT WOS:000172360000016 ER PT J AU Lehoucq, RB AF Lehoucq, RB TI Implicitly restarted Arnoldi methods and subspace iteration SO SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS LA English DT Article DE simultaneous iteration; Arnoldi reduction; Schur decomposition; restarting; eigenvalues ID NONSYMMETRIC EIGENVALUE PROBLEMS; LARGE UNSYMMETRIC EIGENPROBLEMS; COMPUTING SELECTED EIGENVALUES; LANCZOS-ALGORITHM; MATRICES; SPARSE; COMPUTATION; CONVERGENCE; DAVIDSON AB This goal of this paper is to present an elegant relationship between an implicitly restarted Arnoldi method (IRAM) and nonstationary (subspace) simultaneous iteration. This relationship allows the geometric convergence theory developed for nonstationary simultaneous iteration due to Watkins and Elsner [Linear Algebra Appl., 143 (1991), pp. 19-47] to be used for analyzing the rate of convergence of an IRAM. We also comment on the relationship with other restarting schemes. A set of experiments demonstrates that implicit restarted methods can converge at a much faster rate than simultaneous iteration when iterating on a subspace of equal dimension. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Lehoucq, RB (reprint author), Sandia Natl Labs, POB 5800,MS 1110, Albuquerque, NM 87185 USA. NR 41 TC 43 Z9 44 U1 0 U2 0 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0895-4798 J9 SIAM J MATRIX ANAL A JI SIAM J. Matrix Anal. Appl. PD NOV 19 PY 2001 VL 23 IS 2 BP 551 EP 562 DI 10.1137/S0895479899358595 PG 12 WC Mathematics, Applied SC Mathematics GA 505BK UT WOS:000172891000016 ER PT J AU Parra, M Gee, S Ramez, M Gascard, P Mohandas, N Conboy, J AF Parra, M Gee, S Ramez, M Gascard, P Mohandas, N Conboy, J TI Regulation of protein 4.1R gene expression: Complex 5 ' exon structure and apparent coupling between transcription and alternative pre-mRNA splicing events. SO BLOOD LA English DT Meeting Abstract C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 16 PY 2001 VL 98 IS 11 MA 22 BP 8A EP 9A PN 1 PG 2 WC Hematology SC Hematology GA 491WY UT WOS:000172134100023 ER PT J AU Graeber, TG Eisenberg, D AF Graeber, TG Eisenberg, D TI Bioinformatic identification of potential autocrine signaling loops in hematopoietic malignancies from gene expression profiles. SO BLOOD LA English DT Meeting Abstract C1 Univ Calif Los Angeles, US DOE, Lab Struct Biol & Mol Med, Los Angeles, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 16 PY 2001 VL 98 IS 11 MA 4310 BP 158B EP 159B PN 2 PG 2 WC Hematology SC Hematology GA 491WZ UT WOS:000172134200721 ER PT J AU Da Costa, L Narla, G Willig, TN Peters, L Parra, M Fixler, J Tchernia, G Mohandas, N AF Da Costa, L Narla, G Willig, TN Peters, L Parra, M Fixler, J Tchernia, G Mohandas, N TI Functional characterization of transcriptional regulatory elements in ribosomal protein S19 (RPS19) gene, frequently mutated in Diamond-Blackfan Anemia. From transcription to expression of RPS19 during erythropoiesis. SO BLOOD LA English DT Meeting Abstract C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Mt Sinai Med Ctr, New York, NY 10029 USA. Jackson Lab, Bar Harbor, ME 04609 USA. Hop Bicetre, Hematol Lab, Le Kremlin Bicetre, France. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 16 PY 2001 VL 98 IS 11 MA 907 BP 218A EP 218A PN 1 PG 1 WC Hematology SC Hematology GA 491WY UT WOS:000172134100911 ER PT J AU Thornton, MA Cheng, JF Zhang, CY Rubin, EM Poncz, M AF Thornton, MA Cheng, JF Zhang, CY Rubin, EM Poncz, M TI Defining the distal structural and functional organization of the megakaryocyte-specific alpha IIb gene. SO BLOOD LA English DT Meeting Abstract C1 Childrens Hosp, Dept Pediat, Philadelphia, PA 19104 USA. Univ Penn, Philadelphia, PA 19104 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Genome Sci Dept, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 16 PY 2001 VL 98 IS 11 MA 1192 BP 283A EP 283A PN 1 PG 1 WC Hematology SC Hematology GA 491WY UT WOS:000172134101196 ER PT J AU Krauss, SW Lee, JC Lo, AJ Koury, MJ Lee, G Hanspal, M Mohandas, N Chasis, JA AF Krauss, SW Lee, JC Lo, AJ Koury, MJ Lee, G Hanspal, M Mohandas, N Chasis, JA TI Protein sorting during erythroblast enucleation. SO BLOOD LA English DT Meeting Abstract C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. Vanderbilt Univ, Nashville, TN USA. Tufts Univ, St Elizabeths Hosp, Boston, MA 02135 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 16 PY 2001 VL 98 IS 11 MA 1825 BP 435A EP 435A PN 1 PG 1 WC Hematology SC Hematology GA 491WY UT WOS:000172134101829 ER PT J AU Hou, VC Gee, SL Wu, M Turck, CW Koury, M Krainer, AR Mayeda, A Conboy, JG AF Hou, VC Gee, SL Wu, M Turck, CW Koury, M Krainer, AR Mayeda, A Conboy, JG TI Characterization of a second hnRNP A/B-dependent exonic splicing silencer in protein 4.1R exon 16. SO BLOOD LA English DT Meeting Abstract C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Univ Calif San Francisco, San Francisco, CA 94143 USA. Vanderbilt Univ, Nashville, TN USA. Cold Spring Harbor Lab, Cold Spring Harbor, NY 11724 USA. Univ Miami, Sch Med, Miami, FL USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 16 PY 2001 VL 98 IS 11 MA 1827 BP 436A EP 436A PN 1 PG 1 WC Hematology SC Hematology GA 491WY UT WOS:000172134101831 ER PT J AU Caruccio, L Bettinotti, MP Olsen, A Stroncek, DF AF Caruccio, L Bettinotti, MP Olsen, A Stroncek, DF TI Use of bioinformatics to identify the genomic structure of the gene encoding Polycythemia Rubra Vera-1 (PRV-1). SO BLOOD LA English DT Meeting Abstract C1 NIH, Warren Grant Magnuson Clin Ctr, Dept Transfus Med, Bethesda, MD 20892 USA. Lawrence Livermore Natl Lab, Joint Genome Inst, Dept Energy, Walnut Creek, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 16 PY 2001 VL 98 IS 11 MA 1964 BP 470A EP 470A PN 1 PG 1 WC Hematology SC Hematology GA 491WY UT WOS:000172134101968 ER PT J AU Rosario, E Rajendran, J Ruffner, KL Eary, JF Fisher, DR Appelbaum, FR Bernstein, ID Matthews, DC AF Rosario, E Rajendran, J Ruffner, KL Eary, JF Fisher, DR Appelbaum, FR Bernstein, ID Matthews, DC TI Radiolabeled anti-CD45 antibody with cyclophosphamide (CY) and total body irradiation (TBI) followed by allogeneic hematopoietic stem cell transplantation (HSCT) for patients with advanced acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS). SO BLOOD LA English DT Meeting Abstract C1 Fred Hutchinson Canc Res Ctr, Div Clin Res, Seattle, WA 98104 USA. Univ Washington, Dept Pediat, Seattle, WA 98195 USA. Univ Washington, Dept Radiol, Seattle, WA 98195 USA. Univ Washington, Dept Med, Seattle, WA USA. Pacific NW Natl Lab, Richland, WA 99352 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 16 PY 2001 VL 98 IS 11 MA 3558 BP 857A EP 857A PN 1 PG 1 WC Hematology SC Hematology GA 491WY UT WOS:000172134103571 ER PT J AU Wang, DL Lal, J Moses, D Bazan, GC Heeger, AJ AF Wang, DL Lal, J Moses, D Bazan, GC Heeger, AJ TI Small angle neutron scattering (SANS) studies of a conjugated polyelectrolyte in aqueous solution SO CHEMICAL PHYSICS LETTERS LA English DT Article ID INTERACTING RIGID POLYELECTROLYTES; POLY-ELECTROLYTE SOLUTIONS; PERSISTENCE LENGTH; FLUORESCENCE; PHOTOLUMINESCENCE; DERIVATIVES AB Small angle neutron scattering (SANS) by the conjugated polyelectrolyte, poly[5-methoxy-2-(4-sulfobutoxy)-1,4-phenylene-vinylene], was studied in semi-dilute solutions. A broad peak appears at high momentum transfer (q) for all concentrations. The peak position (q(m)) and intensity (I(q(m))) scale with polymer concentration as q(m) similar to c(1/2) and I(q(m))/c similar to c(-1/2), consistent with polyelectrolyte theory. The upturn of I(q) at q < 0.08 (-1) indicates chain aggregation. Addition of excess salt removes the broad peak from I(q). In high-salt solutions, I(q) similar to q(-1) implying a rod-like conformation with a persistence length larger than 800 Angstrom. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Santa Barbara, Inst Polymers & Organ Solids, Dept Phys, Santa Barbara, CA 93106 USA. Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Heeger, AJ (reprint author), Univ Calif Santa Barbara, Inst Polymers & Organ Solids, Dept Phys, Broida Hall 6123, Santa Barbara, CA 93106 USA. RI Bazan, Guillermo/B-7625-2014 NR 35 TC 31 Z9 31 U1 0 U2 15 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 NOV 16 PY 2001 VL 348 IS 5-6 BP 411 EP 415 DI 10.1016/S0009-2614(01)01151-4 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 496TW UT WOS:000172413800010 ER PT J AU Fritz, JS Steiner, SA AF Fritz, JS Steiner, SA TI Effect of a soluble ionic polymer on the separation of anions by capillary electrophoresis SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE coated capillaries; inorganic anions; organic acids ID FUSED-SILICA CAPILLARIES; ZONE ELECTROPHORESIS; ELECTROOSMOTIC FLOW; PROTEINS; LAYERS AB A silica capillary for CE analysis of anions can be conditioned with NaOH, rinsed with water, coated with a cationic polymer, and equilibrated with the background electrolyte in only 2 min for each of the four steps. The coated surface has a positive charge that gives a substantial anodic electroosmotic flow (EOF) over the range of pH 2.5-12.0. The migration times of sample anions and a neutral marker (used for EOF calculations) are generally reproducible to an RSD of 1% or better, both for successive runs on a single capillary and from capillary to capillary. It was shown that the type of buffer used affects the EOF of a coated capillary. A concentration of 100 mM or higher sodium chloride minimizes differences in EOF with different buffers and also gives sharper peaks for sample anions. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Univ Wisconsin Platteville, Dept Chem & Engn Phys, Platteville, WI 53818 USA. RP Fritz, JS (reprint author), Iowa State Univ, US DOE, Ames Lab, 332 Wilhelm Hall, Ames, IA 50011 USA. NR 14 TC 17 Z9 17 U1 0 U2 2 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 NOV 16 PY 2001 VL 934 IS 1-2 BP 87 EP 93 DI 10.1016/S0021-9673(01)01281-X PG 7 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 495RC UT WOS:000172353300008 PM 11762767 ER PT J AU Gao, S Hegg, DA Frick, G Caffrey, PF Pasternack, L Cantrell, C Sullivan, W Ambrusko, J Albrechcinski, T Kirchstetter, TW AF Gao, S Hegg, DA Frick, G Caffrey, PF Pasternack, L Cantrell, C Sullivan, W Ambrusko, J Albrechcinski, T Kirchstetter, TW TI Experimental and modeling studies of secondary organic aerosol formation and some applications to the marine boundary layer SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID CLOUD-CONDENSATION-NUCLEI; SOLUBLE DICARBOXYLIC-ACIDS; PARTICULATE PRODUCTS; ATMOSPHERIC PARTICLES; ABSORPTION-MODEL; NUCLEATION; OZONE; WATER; MECHANISM; OXIDATION AB A series of controlled experiments were carried out in the Calspan Corporation's 600 m(3) environmental chamber to study some secondary organic aerosol formation processes. Three precursor-ozone systems were studied: cyclopentene-ozone, cyclohexene-ozone, and alpha -pinene-ozone. Additionally, SO2 was added to the initial gas mixture in several instances and was likely present at trace levels in the ostensibly organic-only experiments. It was found that all three systems readily formed new submicron aerosols at very low reactant levels. The chemical composition of formed aerosols was consistent with some previous studies, but the yields of organic products were found to be lower in the Calspan experiments. A three-step procedure is proposed to explain the observed particle nucleation behavior: HO. production --> H2SO4 formation --> H2SO4-H2O (perhaps together with NH3) homogeneous nucleation. It is also proposed that some soluble organic products would partition into the newly formed H2SO4-H2O nuclei, enhance water condensation, and quickly grow these nuclei into a larger size range. While the observations in the two cycloolefin-ozone systems could be well explained by these proposed mechanisms, the exact nature of the nucleation process in the alpha -pinene-ozone system remains rather opaque and could be the result of nucleation involving certain organics. The results from three simple modeling studies further support these proposals. Their applicability to the marine boundary layer (MBL) is also discussed in some detail. Particularly, such a particle nucleation and growth process could play an important role in secondary aerosol formation and, quite likely, CCN formation as well in certain MBL regions. C1 Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA. Calspan Univ Buffalo, Res Ctr, Buffalo, NY 14225 USA. USN, Res Lab, Washington, DC 20375 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Washington, Dept Chem, Seattle, WA 98195 USA. RP Univ Washington, Dept Atmospher Sci, Box 351640, Seattle, WA 98195 USA. EM sgao@u.washington.edu; deanhegg@atmos.washington.edu NR 62 TC 24 Z9 25 U1 1 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD NOV 16 PY 2001 VL 106 IS D21 BP 27619 EP 27634 DI 10.1029/2001JD900170 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 494XZ UT WOS:000172312300028 ER PT J AU Kevrekidis, PG Malomed, BA Bishop, AR AF Kevrekidis, PG Malomed, BA Bishop, AR TI Bound states of two-dimensional solitons in the discrete nonlinear Schrodinger equation SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article ID WAVE-GUIDE ARRAYS; SELF-TRAPPING EQUATION; LOCALIZED MODES; INTERNAL-MODES; 2-DIMENSIONAL SOLITONS; OPTICAL SOLITONS; FIBER ARRAYS; BREATHERS; LATTICES; EXISTENCE AB The existence and stability of bound states (BSs) of solitary excitations in the two-dimensional discrete nonlinear Schrodinger lattice are considered. Stable BSs of two or three solitons are categorized according to their vorticity S (S = 0 corresponds to ordinary pulses, while S = I corresponds to discrete vortex solitons). Interactions of S = 0 solitons are found to have clear particle-like characteristics, which can be very accurately predicted in the framework of the perturbation theory that we develop. Triangular bound states of three solitons are also constructed, and particle-like characteristics in their behaviour are followed in numerical experiments. Finally, stable bound states of two vortex solitons, and S = 0-1 stable complexes are constructed. For the latter state, we find a weak dependence of the interaction-generated stability eigenvalue on the distance between the two solitons. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Univ Massachusetts, Dept Math & Stat, Amherst, MA 01003 USA. Tel Aviv Univ, Fac Engn, Dept Interdisciplinary Studies, IL-69978 Tel Aviv, Israel. RP Kevrekidis, PG (reprint author), Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. NR 58 TC 30 Z9 30 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD NOV 16 PY 2001 VL 34 IS 45 BP 9615 EP 9629 DI 10.1088/0305-4470/34/45/302 PG 15 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 500FW UT WOS:000172616600002 ER PT J AU Baugh, J Kleinhammes, A Han, DX Wang, Q Wu, Y AF Baugh, J Kleinhammes, A Han, DX Wang, Q Wu, Y TI Confinement effect on dipole-dipole interactions in nanofluids SO SCIENCE LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; A-SI-H; MOLECULAR-HYDROGEN; QUANTUM COHERENCES; AMORPHOUS-SILICON; LIQUID NMR; RELAXATION AB Intermolecular dipole-dipole interactions were once thought to average to zero in gases and Liquids as a result of. rapid molecular motion that leads to sharp nuclear magnetic resonance lines. Recent papers have shown that small residual couplings survive the motional averaging if the magnetization is nonuniform or nonspherical Here, we show that a much larger, qualitatively different intermolecular dipolar interaction remains in nanogases and nanoliquids: as an effect of confinement. The dipolar coupling that characterizes such interactions is identical for all spin pairs and depends on the shape, orientation (with respect to the external magnetic field), and volume of the gas/liquid container. This nanoscale effect is useful in the determination of nanostructures and could have unique applications in the exploration of quantum space. C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wu, Y (reprint author), Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. RI Baugh, Jonathan/F-3879-2011 NR 22 TC 54 Z9 56 U1 3 U2 21 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 NOV 16 PY 2001 VL 294 IS 5546 BP 1505 EP 1507 DI 10.1126/science.1065373 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 493TX UT WOS:000172240500041 PM 11711669 ER PT J AU Buranda, T Lopez, GP Simons, P Pastuszyn, A Sklar, LA AF Buranda, T Lopez, GP Simons, P Pastuszyn, A Sklar, LA TI Detection of epitope-tagged proteins in flow cytometry: Fluorescence resonance energy transfer-based assays on beads with femtomole resolution SO ANALYTICAL BIOCHEMISTRY LA English DT Article DE flow cytometry; fluorescence; energy transfer; quenching; biosensors ID REAL-TIME ANALYSIS; MONOCLONAL-ANTIBODY; DRUG DISCOVERY; PURIFICATION; RECEPTOR; PEPTIDES; LIGAND; SYSTEM AB Epitope tagging of expressed proteins is a versatile tool for the detection and purification of the proteins. This approach has been used in protein-protein interaction studies, protein localization, and immunoprecipitation. Among the most popular tag systems is the FLAG epitope tag, which is recognized by three monoclonal antibodies M1, M2, and M5. We describe novel approaches to the detection of epitope-tagged proteins via fluorescence resonance energy transfer on beads. We have synthesized and characterized biotinylated and fluorescein-labeled FLAG peptides and examined the binding of FLAG peptides to commercial streptavidin beads using flow cytometric analysis. A requirement of assay development is the elucidation of parameters that characterize the binding interactions between component systems. We have thus compiled a set of Kd values determined from a series of equilibrium binding experiments with beads, peptides, and antibodies. We have defined conditions for binding biotinylated and fluoresceinated FLAG peptides to beads. Site occupancies of the peptides were determined to be on the order of several million sites per bead and K-d values in the 0.3-2.0 nM range. The affinity for antibody attachment to peptides was determined to be in the low nanomolar range (less than 10 nM) for measurements on beads and solution. We demonstrate the applicability of this methodology to assay development, by detecting femtomole amounts of N-terminal FLAG-bacteria alkaline phosphatase fusion protein. These characterizations form the basis of generalizable and high throughput assays for proteins with known epitopes, for research, proteomic, or clinical applications. (C) 2001 Academic Press. C1 Univ New Mexico, Sch Med, Dept Pathol, Albuquerque, NM 87131 USA. Univ New Mexico, Sch Med, Dept Biochem & Mol Biol, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. RP Sklar, LA (reprint author), Univ New Mexico, Sch Med, Ctr Canc, Albuquerque, NM 87131 USA. FU NCRR NIH HHS [RR-01315]; NIGMS NIH HHS [GM60799-02] NR 28 TC 27 Z9 31 U1 0 U2 6 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 NOV 15 PY 2001 VL 298 IS 2 BP 151 EP 162 DI 10.1006/abio.2001.5363 PG 12 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 497JK UT WOS:000172451600002 PM 11700971 ER PT J AU Maizels, M Budde, WL AF Maizels, M Budde, WL TI Exact mass measurements for confirmation of pesticides and herbicides determined by liquid chromatography/time-of-flight mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article AB The accuracy and precision of exact mass measurements are determined using positive ions formed in the electrospray of 10 nonvolatile or thermally unstable carbamate, urea, and thiourea pesticides and herbicides. Environmentally significant similar to 7-ng quantities of the analytes were separated with microbore liquid chromatography, and the exact mass measurements were made in real time with a benchtop time-of-flight mass spectrometer. The positive ion electrospray mass spectra of the analytes generally consist of one or a few ions which are usually adducts of the molecule with a proton, a sodium ion, or an ammonium ion. Fragment ions and the rich mass spectra typical of electron ionization (EI) are generally not produced in the soft electrospray ionization process. Confirmation of the identity of a nonvolatile pesticide or herbicide depends largely on the masses of the few ions formed and the retention time, which can vary with chromatography conditions. Identifications of these analytes in environmental or other samples are less certain than identifications of volatile pesticides determinated by gas chromatography and El mass spectrometry. The benchtop time-of-flight mass spectrometer was equipped with an electrostatic mirror, and resolving powers of 3500-5000 were routinely obtained and used for these exact mass measurements. This type of mass spectrometer is significantly less costly and complex than other types of mass spectrometers with exact mass measurement capabilities. The mean errors from three replicate exact mass measurements of the 10 test analytes were in the range of 0-5.4 parts-per-million. Potential interferences from substances with similar exact masses were evaluated. C1 US EPA, Off Res & Dev, Natl Exposure Res Lab, Cincinnati, OH 45268 USA. Oak Ridge Inst Sci & Educ, Cincinnati, OH 45268 USA. RP Budde, WL (reprint author), US EPA, Off Res & Dev, Natl Exposure Res Lab, 26 W Martin L King Dr, Cincinnati, OH 45268 USA. NR 9 TC 39 Z9 41 U1 4 U2 8 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 NOV 15 PY 2001 VL 73 IS 22 BP 5436 EP 5440 DI 10.1021/ac010601o PG 5 WC Chemistry, Analytical SC Chemistry GA 493EQ UT WOS:000172209400012 PM 11816570 ER PT J AU Da Costa, L Mohandas, N Sorette, M Grange, MJ Tchernia, G Cynober, T AF Da Costa, L Mohandas, N Sorette, M Grange, MJ Tchernia, G Cynober, T TI Temporal differences in membrane loss lead to distinct reticulocyte features in hereditary spherocytosis and in immune hemolytic anemia SO BLOOD LA English DT Article ID CELL DEFORMABILITY; TERMINAL DIFFERENTIATION; HEMOGLOBIN CONCENTRATION; SURFACE-AREA; MATURATION; SPLEEN; VOLUME; ERYTHROCYTES; EKTACYTOMETRY; DIAGNOSIS AB Spherocytic red cells with reduced membrane surface area are a feature of hereditary spherocytosis (HS) and some forms of autoimmune hemolytic anemia (AIHA). It is generally assumed that membrane loss in spherocytic red cells occurs during their sojourn in circulation. The structural basis for membrane loss in HS is improper assembly of membrane proteins, whereas In AIHA it is due to partial phagocytosis of circulating red cells by macrophages. A hypothesis was formed that these different mechanisms should lead to temporal differences in surface area loss during red cell genesis and during sojourn in circulation in these 2 spherocytic syndromes. It was proposed that cell surface loss could begin at the reticulocyte stage In HS, whereas surface area loss in ANA involves only circulating mature red cells. The validity of this hypothesis was established by documenting differences in cellular features of reticulocytes in HS and AIHA. Using a novel technique to quantitate cell surface area, the decreased membrane surface area of both reticulocytes and mature red cells in HIS compared with normal cells was documented. In contrast, in AIHA only mature red cells but not reticulocytes exhibited decreased membrane surface area. These data imply that surface area loss in HS, but not In ANA, is already present at the circulating reticulocyte stage. These findings imply that loss of cell surface area is an early event during genesis of HS red cells and challenge the existing concepts that surface area loss in HS occurs predominantly during the sojourn of mature red cells in circulation. (C) 2001 by The American Society of Hematology. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Hop Bicetre, INSERM, U473,Lab Hematol, Fac Med Paris 11,AP HP, Le Kremlin Bicetre, France. Bayer Diagnost, Tarrytown, NY USA. Hop Bichat Claude Bernard, Lab Hematol, Paris, France. RP Mohandas, N (reprint author), Lawrence Berkeley Natl Lab, Mailstop 74-157,1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NIDDK NIH HHS [DK26263] NR 49 TC 32 Z9 32 U1 0 U2 2 PU AMER SOC HEMATOLOGY PI WASHINGTON PA 1900 M STREET. NW SUITE 200, WASHINGTON, DC 20036 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 15 PY 2001 VL 98 IS 10 BP 2894 EP 2899 DI 10.1182/blood.V98.10.2894 PG 6 WC Hematology SC Hematology GA 492PW UT WOS:000172177600004 PM 11698268 ER PT J AU Smith, DR Chandra, S Barth, RF Yang, WL Joel, DD Coderre, JA AF Smith, DR Chandra, S Barth, RF Yang, WL Joel, DD Coderre, JA TI Quantitative imaging and microlocalization of boron-10 in brain tumors and infiltrating tumor cells by SIMS ion microscopy: Relevance to neutron capture therapy SO CANCER RESEARCH LA English DT Article ID ATOMIC EMISSION-SPECTROSCOPY; P-BORONOPHENYLALANINE; GLIOBLASTOMA-MULTIFORME; CULTURED-CELLS; TISSUES; COMPLEX; GLIOMA AB Boron neutron capture therapy (BNCT) is dependent on the selective accumulation of boron-10 in tumor cells relative to the contiguous normal cells. Ion microscopy was used to evaluate the microdistribution of boron-10 from p-boronophenylalanine (BPA) in the 9L rat gliosarcoma and the F98 rat glioma brain tumor models. Four routes of BPA administration were used: i.p. injection, intracarotid (i.c.) injection [with and without blood-brain barrier disruption (BBB-D)], and continuous timed Lv. infusions. i.p. injection of BPA in the 9L gliosarcoma resulted in a tumor-to-brain (T:Br) boron-10 concentration ratio of 3.7:1 when measured at the tumor-normal brain interface. In the F98 glioma, he injection of BPA resulted in a T:Br ratio of 2.9:1, and this increased to 5.4:1 when BBB-D was performed. The increased tumor boron uptake would potentially enhance the therapeutic ratio of BNCT by >25%. At present, ion microscopy is the only technique to provide a direct measurement of the T:Br boron-10 concentration ratio for tumor cells infiltrating normal brain. In the 9L gliosarcoma, this ratio was 2.9:1 after i.p. administration. In the F98 glioma, Le injection resulted in a ratio of 2.2:1, and this increased to 3.0:1 after BBB-D. Ion microscopy revealed a consistent pattern of boron-10 microdistribution for both rat brain tumor models. The boron-10 concentration in the main tumor mass (MTM) was approximately twice that of the infiltrating tumor cells. One hour after a 2-h i.v. infusion of BPA in rats with the 9L gliosarcoma, tumor boron-10 concentrations were 2.7 times higher than that of infiltrating tumor cells [83 +/- 23 mug/g tissue versus 31 +/- 12 mug/g tissue (mean +/- SD)]. Continuous 3- and 6-h i.v. infusions of BPA in the 9L gliosarcoma resulted in similar high boron-10 concentrations in the MTM, The boron-10 concentration in infiltrating tumor cells was two times lower than the MTM after a 3-h infusion. After 6 h, the boron-10 concentration in infiltrating tumor cells had increased nearly 90% relative to the 2- and 3-h infusions. A 24-h i.v. infusion resulted in similar boron-10 levels between the MTM and the infiltrating tumor cells. Boron concentrations in the normal brain were similar for all four infusion times (similar to 20 mug/g tissue). These results are important for BNCT, because clinical protocols using a 2-h infusion have been performed with the assumption that infiltrating tumor cells contain equivalent amounts of boron-10 as the MTM. The results reported here suggest that this is not the case and that a 6-h or longer infusion of BPA may be necessary to raise boron-10 levels in infiltrating tumor cells to that in the MTM. C1 Cornell Univ, Dept Chem & Biol Chem, Ithaca, NY 14853 USA. Ohio State Univ, Dept Pathol, Columbus, OH 43210 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Smith, DR (reprint author), Cornell Univ, Dept Chem & Biol Chem, Ithaca, NY 14853 USA. NR 36 TC 84 Z9 84 U1 2 U2 13 PU AMER ASSOC CANCER RESEARCH PI BIRMINGHAM PA PO BOX 11806, BIRMINGHAM, AL 35202 USA SN 0008-5472 J9 CANCER RES JI Cancer Res. PD NOV 15 PY 2001 VL 61 IS 22 BP 8179 EP 8187 PG 9 WC Oncology SC Oncology GA 495AF UT WOS:000172317500023 PM 11719448 ER PT J AU Tapponnier, P Ryerson, FJ Van der Woerd, J Meriaux, AS Lasserre, C AF Tapponnier, P Ryerson, FJ Van der Woerd, J Meriaux, AS Lasserre, C TI Long-term slip rates and characteristic slip: keys to active fault behaviour and earthquake hazard SO COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE II FASCICULE A-SCIENCES DE LA TERRE ET DES PLANETES LA English DT Article; Proceedings Paper CT Conference on Earthquakes CY MAR 20, 2000 CL PARIS, FRANCE DE cosmogenic dating; active faults of Asia; sliprates; characteristic slip; earthquake recurrence and hazard ID WESTERN HAIYUAN FAULT; SAN-ANDREAS FAULT; FLUVIAL TERRACES; GANSU; RECURRENCE; CALIFORNIA; CHINA; QUATERNARY; SURFACES; QINGHAI AB Over periods of thousands of years, active faults tend to slip at constant rates. Pioneer studies of large Asian faults show that cosmogenic radionuclides (Be-10, Al-26) provide an unparalleled tool to date surface features, whose offsets yield the longest records of recent cumulative movement. The technique is thus uniquely suited to determine long-term (10-100 ka) slip rates. Such rates, combined with coseismic slip-amounts, can give access to recurrence times of earthquakes of similar sizes. Landform dating morphochronology - is therefore essential to understand fault-behaviour, evaluate seismic hazard, and build physical earthquake models. It is irreplaceable because long-term slip-rates on interacting faults need not coincide with GPS-derived, interseismic rates, and can be difficult to obtain from paleo-seismological trenching. (C) 2001 Academie des sciences Editions scientifiques et medicales Elsevier SAS. C1 Inst Phys Globe, F-75252 Paris 05, France. Lawrence Livermore Natl Lab, IGPP, Livermore, CA 94550 USA. RP Tapponnier, P (reprint author), Inst Phys Globe, 4 Pl Jussieu, F-75252 Paris 05, France. EM tappon@ipgp.jussieu.fr RI Meriaux, Anne-Sophie/G-1754-2010; Tapponnier, .Paul/B-7033-2011; Lasserre, Cecile/D-7073-2017 OI Tapponnier, .Paul/0000-0002-7135-1962; Lasserre, Cecile/0000-0002-0582-0775 NR 27 TC 53 Z9 60 U1 0 U2 5 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 1251-8050 J9 CR ACAD SCI II A JI Comptes Rendus Acad. Sci. Ser II-A PD NOV 15 PY 2001 VL 333 IS 9 BP 483 EP 494 DI 10.1016/S1251-8050(01)01668-8 PG 12 WC Geosciences, Multidisciplinary SC Geology GA 505DV UT WOS:000172897000002 ER PT J AU Sanchez, R Isaev, MY Hirshman, SP Cooper, WA Fu, GY Jimenez, JA Ku, LP Mikhailov, MI Monticello, DA Reiman, AH Subbotin, AA AF Sanchez, R Isaev, MY Hirshman, SP Cooper, WA Fu, GY Jimenez, JA Ku, LP Mikhailov, MI Monticello, DA Reiman, AH Subbotin, AA TI Ideal MHD stability calculations for compact stellarators SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article DE stellarators; low aspect ratio; magnetohydrodynamics; ideal pressure-driven instabilities; interchange and ballooning modes; magnetic coordinates ID MAGNETOHYDRODYNAMIC STABILITY; BALLOONING STABILITY; CONFIGURATIONS; PLASMA; OPTIMIZATION; PHYSICS; DESIGN; MODES; BETA AB Stability results for high-n ideal local pressure-driven instabilities (ballooning and interchange: modes) are calculated from the COBRA and TERPSICHORE codes and compared for several low aspect ratio stellarators. Such a comparison is important because of the predominant roles that these codes are playing in the design of compact stellarators at several laboratories around the world. The code development required to reach the levels of convergence and accuracy needed for reliable operation at low aspect ratios is also described. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Carlos III Madrid, Dept Fis, Madrid, Spain. RRC Kurchatov Inst, Nucl Fus Inst, Moscow, Russia. Oak Ridge Natl Lab, Oak Ridge, TN USA. Ecole Polytech Fed Lausanne, Assoc Euratom Suisse, Ctr Rech Phys Plasmas, PPB,CRPP, Lausanne, Switzerland. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. CIEMAT, Asociac Eurotom, E-28040 Madrid, Spain. RP Sanchez, R (reprint author), Univ Carlos III Madrid, Dept Fis, Madrid, Spain. EM rsanchez@fis.uc3m.es RI Sanchez, Raul/C-2328-2008; Jimenez, Juan/A-5245-2017; Isaev, Maxim/A-7910-2012 OI Jimenez, Juan/0000-0003-3453-2470; Isaev, Maxim/0000-0002-8492-0650 NR 35 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 EI 1879-2944 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD NOV 15 PY 2001 VL 141 IS 1 BP 55 EP 65 DI 10.1016/S0010-4655(01)00396-4 PG 11 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 494HC UT WOS:000172275000004 ER PT J AU Di Pierro, M AF Di Pierro, M TI Matrix distributed processing: a set of C++ tools for implementing generic lattice computations on parallel systems SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article DE lattice; parallel computing; numerical software ID SIMULATIONS AB We present a set of programming tools (classes and functions written in C++ and based on Message Passing Interface) for fast development of generic parallel (and non-parallel) lattice simulations. They are collectively called MDP 1. 2. These programming tools include classes and algorithms for matrices, random number generators, distributed lattices (with arbitrary topology), fields and parallel iterations. No previous knowledge of MPI is required in order to use them. Some applications in electromagnetism, electronics, condensed matter and lattice QCD are presented, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Di Pierro, M (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 11 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD NOV 15 PY 2001 VL 141 IS 1 BP 98 EP 148 DI 10.1016/S0010-4655(01)00297-1 PG 51 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 494HC UT WOS:000172275000008 ER PT J AU Oktay, SD Santschi, PH Moran, JE Sharma, P AF Oktay, SD Santschi, PH Moran, JE Sharma, P TI I-129 and I-127 transport in the Mississippi River SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID DISSOLVED ORGANIC-MATTER; GULF-OF-MEXICO; CROSS-FLOW ULTRAFILTRATION; I-129/I-127 RATIOS; CHESAPEAKE-BAY; TRACE-METALS; CARBON; ENVIRONMENT; COLLOIDS; RADIONUCLIDES AB The watershed processes which control I-129/I-127 ratios, I-129 and I-127 concentrations, and speciation of iodine isotopes were studied through an investigation into the variability of these parameters in the Mississippi River near New Orleans, undertaken in 1996-1998. Analyses of suspended particulate matter (SPM) revealed a greater percent association of I-127 than of I-129, resulting in lower I-129/I-127 ratios in SPM than in surrounding water. Furthermore, crossflow ultrafiltration showed that organo-iodine was the dominant form for both isotopes, with 70-85% of these isotopes found in the 0.45 mum filter-passing fraction associated with colloidal macromolecular organic matter, I-129 showed a weak correlation, I-127 no correlation, and I-129/I-127 ratios a strong inverse correlation with river flow rate. Inverse correlations between I-129/I-127 ratios and river flow rates can be best explained by rainwater and evapotranspiration dominated ratios at base flow and a lowering of the isotope ratios during higher flow due to extra inputs of I-127 from soil weathering. We postulate that different equilibration times for I-127 and I-129 as well as for bomb-produced I-129 and reprocessing-produced I-129 are responsible for these fractionation effects and the differential mobilities of these isotopes in the Mississippi River watershed. C1 Texas A&M Univ, Dept Oceanog, Galveston, TX 77551 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Purdue Univ, PRIME Lab, W Lafayette, IN 47907 USA. RP Santschi, PH (reprint author), Texas A&M Univ, Dept Oceanog, 5007 Ave U, Galveston, TX 77551 USA. RI Santschi, Peter/D-5712-2012 NR 57 TC 40 Z9 40 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD NOV 15 PY 2001 VL 35 IS 22 BP 4470 EP 4476 DI 10.1021/es0109444 PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 492PX UT WOS:000172177700011 PM 11757603 ER PT J AU Bickmore, BR Nagy, KL Young, JS Drexler, JW AF Bickmore, BR Nagy, KL Young, JS Drexler, JW TI Nitrate-cancrinite precipitation on quartz sand in simulated Hanford tank solutions SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID POLYSILICATE FORMATION; CRYSTAL-STRUCTURE; AQUEOUS-SOLUTION; SILICIC-ACID; NMR; SOLUBILITY; KINETICS; ALUMINUM; DISSOLUTION; EQUILIBRIA AB Caustic NaNO3 Solutions containing dissolved Al were reacted with quartz sand at 89 degreesC to simulate possible reactions between leaked nuclear waste and primary subsurface minerals at the U.S. Department of Energy's Hanford site in Washington. Nitrate-cancrinite began to precipitate onto the quartz after 2-10 days, cementing the grains together. Estimates of the equilibrium constant for the precipitation reaction differ for solutions with 0.1 or 1.0 m OH- (log K-eq = 30.4 +/- 0.8 and 36.2 +/- 0.6, respectively). The difference in solubility may be attributable to more perfect crystallinity (i.e., fewer stacking faults) in the higher-pH cancrinite structure. This is supported by electron micrographs of crystal morphology and measured rates of Na volatilization under an electron beam. Precipitate crystallinity may affect radionuclide mobility, because stacking faults in the cancrinite structure can diminish its zeolitic cation exchange properties. The precipitation rate near the onset of nucleation depends on the total Al and Si concentrations in solution. The evolution of experimental Si concentrations was modeled by considering the dependence of quartz dissolution rate on Al(OH)(4)(-) activity, cancrinite precipitation, and the reduction of reactive surface area of quartz due to coverage by cancrinite. C1 Univ Colorado, Dept Geol Sci, Boulder, CO 80309 USA. Pacific NW Natl Lab, William R Wiley Enivironm Mol Sci Lab, Richland, WA 99301 USA. RP Bickmore, BR (reprint author), Brigham Young Univ, Dept Geol, Provo, UT 84602 USA. EM Barry_Bickmore@byu.edu NR 39 TC 73 Z9 73 U1 3 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X EI 1520-5851 J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD NOV 15 PY 2001 VL 35 IS 22 BP 4481 EP 4486 DI 10.1021/es0108234 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 492PX UT WOS:000172177700013 PM 11757605 ER PT J AU Gosling, JT Skoug, RM Feldman, WC AF Gosling, JT Skoug, RM Feldman, WC TI Solar wind electron halo depletions at 90 degrees pitch angle SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HELIOS PLASMA-EXPERIMENT; ULYSSES OBSERVATIONS; BOW SHOCK AB Strong depletions in solar wind electron halo distribution functions, centered on and roughly symmetric about 90 degrees pitch angle, are present in at least 10 % of data obtained by the Los Alamos SWEPAM experiment on the ACE spacecraft. Sunward-directed conics are also present in the electron data, occur in conjunction with the 90 degrees depletions, but are less common than depletions. We suggest that on open field lines both depictions and conics arise from focusing and mirroring effects associated with field line connection to magnetic field enhancements further out in the heliosphere. The focusing and mirroring produces field-aligned, counterstreaming fluxes of suprathermal electrons somewhat similar to that observed on closed field lines. Our observations provide strong evidence that the antisunward-directed portion of the electron halo on open field lines at times results primarily from mirroring of back scattered strahl and/or shock-heated electrons from far out in the heilosphere. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Gosling, JT (reprint author), Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. NR 15 TC 61 Z9 61 U1 0 U2 2 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 NOV 15 PY 2001 VL 28 IS 22 BP 4155 EP 4158 DI 10.1029/2001GL013758 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 490CG UT WOS:000172032400001 ER PT J AU Sun, S Bleck, R AF Sun, S Bleck, R TI Atlantic thermohaline circulation and its response to increasing CO2 in a coupled atmosphere-ocean model SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID NORTH-ATLANTIC; CLIMATE-CHANGE; COORDINATE; TEMPERATURE AB We discuss aspects of the Atlantic thermohaline circulation (THC) and its response to increased greenhouse gas concentration, using a coupled atmosphere-ocean general circulation model (AOGCM) whose oceanic component is a now hybrid-isopycnal model. Two 200-year model integrations are carried out - a control run assuming fixed atmospheric composition and a perturbation run assuming gradual doubling of CO2. We employ no flux corrections at the air-sea interface, nor do we spin up the ocean prior to coupling. The surface conditions in the control run stabilize after several decades. When doubling CO2 at the rate of 1% per year, the model responds with a 2 degreesC increase in global mean surface air temperature (SAT) after 200 years and a virtually unchanged Atlantic meridional overturning circulation. The latter is maintained by a salinity increase that counteracts the effect of global warming on the surface buoyancy. C1 NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sun, S (reprint author), NASA, Goddard Inst Space Studies, 2880 Broadway, New York, NY 10025 USA. RI Sun, Shan/H-2318-2015 NR 21 TC 18 Z9 20 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 NOV 15 PY 2001 VL 28 IS 22 BP 4223 EP 4226 DI 10.1029/2001GL013325 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 490CG UT WOS:000172032400018 ER PT J AU Stockman, HW Johnson, J Brown, SR AF Stockman, HW Johnson, J Brown, SR TI Mixing at fracture intersections: influence of channel geometry and the Reynolds and Peclet numbers SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID LATTICE-BOLTZMANN; MODELS; DISPERSION; JUNCTIONS AB The 3D lattice Boltzmann (LB) method was used to model mixing at three types of continuous fracture intersections: planar, fluted (containing parallel grooves), and rough-walled. Peclet number (Pe) varied from 3 to 400, and Reynolds number (Re) varied from 0.5 to 100. In both planar- and rough-walled intersections, the mixing ratio (M-r) decreases with increasing Pe, though the decrease is less dramatic for the rough-walled geometry, In planar-walled intersections, the Al,. decreases with increasing Re; however, the fluted and rough-walled intersections show the opposite trend. Overall, the impact of inertial effects is slight for Re less than or equal to 10. The effects of channel length are also small; the calculated. M-r varies little for LB simulations with length/width greater than or equal to 1. C1 Sandia Natl Labs, Geochem Dept 6118, Albuquerque, NM 87185 USA. New England Res Inc, White River Jct, VT 05001 USA. RP Stockman, HW (reprint author), Sandia Natl Labs, Geochem Dept 6118, POB 5800, Albuquerque, NM 87185 USA. RI Johnson, Joel/B-8842-2012 NR 9 TC 13 Z9 14 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 NOV 15 PY 2001 VL 28 IS 22 BP 4299 EP 4302 DI 10.1029/2001GL013287 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 490CG UT WOS:000172032400037 ER PT J AU Hebner, GA Abraham, IC AF Hebner, GA Abraham, IC TI Characterization of electron and negative ion densities in fluorocarbon containing inductively driven plasmas SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID PHOTODETACHMENT CROSS-SECTION; COUPLED DISCHARGES; REFERENCE CELL; C4F8 PLASMA; SPECTROSCOPY; FLUORINE; C2F6; CHF3 AB Electron and negative ion densities were measured in inductively coupled discharges containing C4F8. In addition, the identity of the negative ions in C2F6, CHF3, and C4F8 containing discharges was investigated with a photodetachment experiment utilizing a microwave resonant cavity structure. To investigate the influence of surface material, the rf-biased electrode was covered with a silicon wafer or a fused silica (SiO2) wafer. Line-integrated electron density was determined using a microwave interferometer, and absolute negative ion densities in the center of the plasma were inferred using laser photodetachment spectroscopy. Voltage and current at the induction coil and rf-biased electrode were also measured for both surfaces as functions of induction coil power, pressure, and rf bias. For the range of induction powers, pressures, and bias power investigated, the electron density peaked at 6x10(12) cm(-2) (line integrated), or approximately 6x10(11) cm(-3). The negative ion density peaked at approximately 2.2x10(11) cm(-3). In most cases, the trends in the electron and negative ion densities were independent of the wafer material. However, a maximum in the negative ion density as a function of induction coil power was observed above a silicon wafer. The maximum is attributed to a power-dependent change in the density of one or more of the potential negative ion precursor species. A microwave resonant cavity structure was developed to identify the negative ions using laser photodetachment spectroscopy. The technique was demonstrated for inductively coupled discharges containing C4F8, C2F6, and CHF3. Scanning the laser wavelength over the range of the F- photodetachment energy indicated that while the dominant negative ion appeared to be F-, weak evidence for other molecular negative ions was observed. Unlike traditional microwave cavity techniques, this method offers the possibility of spatial resolution. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hebner, GA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 23 TC 30 Z9 30 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 15 PY 2001 VL 90 IS 10 BP 4929 EP 4937 DI 10.1063/1.1410896 PG 9 WC Physics, Applied SC Physics GA 488CW UT WOS:000171918700006 ER PT J AU Hebner, GA AF Hebner, GA TI Spatially resolved SiF and SiF2 densities in inductively driven discharges containing C2F6 and C4F8 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID LASER-INDUCED FLUORESCENCE; ETCHING PLASMAS; REFERENCE CELL; ION; SPECTROSCOPY; PRODUCT; CHF3; CF4; GAS AB Laser-induced fluorescence was used to measure the spatially resolved SiF and SiF2 radical densities in inductively driven discharges containing fluorocarbon gases. Measurements of the spatially resolved SiF and SiF2 densities were performed in C2F6 and C4F8 discharges as functions of the induction coil power, pressure, and bias power above a silicon surface. The SiF density had a maximum at a radial distance of 2-3 cm from the center of the plasma, and then monotonically decreased towards the edge of the plasma region. While the density was a function of the plasma parameters, the general shape of the SiF spatial distribution was generally independent of the plasma conditions and gas. The SiF2 density had a maximum at a radial distance of approximately 7 cm from the center of the plasma. At this location, the SiF2 plasma-induced optical emission was approximately 10% of the value in the center of the discharge. The SiF2 spatial distribution was dependent on the induction coil power. The location of the peak in the SiF2 density did not depend on the plasma confinement structures or material. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hebner, GA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 18 TC 9 Z9 9 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 15 PY 2001 VL 90 IS 10 BP 4938 EP 4945 DI 10.1063/1.1410897 PG 8 WC Physics, Applied SC Physics GA 488CW UT WOS:000171918700007 ER PT J AU Mahan, AH Xu, Y Williamson, DL Beyer, W Perkins, JD Vanecek, M Gedvilas, LM Nelson, BP AF Mahan, AH Xu, Y Williamson, DL Beyer, W Perkins, JD Vanecek, M Gedvilas, LM Nelson, BP TI Structural properties of hot wire a-Si : H films deposited at rates in excess of 100 A/s SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID HYDROGENATED AMORPHOUS-SILICON; ALLOY SOLAR-CELLS; I-LAYERS; MICROVOIDS; DEFECT; MICROCRYSTALLINITY; MICROSTRUCTURE; TEMPERATURE; SCATTERING; MECHANISM AB The structure of a-Si:H, deposited at rates in excess of 100 Angstrom /s by the hot wire chemical vapor deposition technique, has been examined by x-ray diffraction (XRD), Raman spectroscopy, H evolution, and small-angle x-ray scattering (SAXS). The films examined in this study were chosen to have roughly the same bonded H content C-H as probed by infrared spectroscopy. As the film deposition rate R-d is increased from 5 to > 140 Angstrom /s, we find that the short range order (from Raman), the medium range order (from XRD), and the peak position of the H evolution peak are invariant with respect to deposition rate, and exhibit structure consistent with a state-of-the-art, compact a-Si:H material deposited at low deposition rates. The only exception to this behavior is the SAXS signal, which increases by a factor of similar to 100 over that for our best, low H content films deposited at similar to5 Angstrom /s. We discuss the invariance of the short and medium range order in terms of growth models available in the literature, and relate changes in the film electronic structure (Urbach edge, as-grown defect density) to the increase in the SAXS signals. We also note the invariance of the saturated defect density versus R-d, measured after light soaking, and discuss possible reasons why the increase in the microvoid density apparently does not play a role in the Staebler-Wronski effect for this type of material. (C) 2001 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Colorado Sch Mines, Dept Phys, Golden, CO 80401 USA. Forschungszentrum Julich, Julich, Germany. Acad Sci Czech Republic, Inst Phys, Prague 6, Czech Republic. RP Natl Renewable Energy Lab, Golden, CO 80401 USA. EM hmahan@nrel.gov RI Vanecek, Milan/H-1995-2014 NR 56 TC 56 Z9 56 U1 2 U2 10 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 NOV 15 PY 2001 VL 90 IS 10 BP 5038 EP 5047 DI 10.1063/1.1407317 PG 10 WC Physics, Applied SC Physics GA 488CW UT WOS:000171918700022 ER PT J AU Cook, BA Harringa, JL AF Cook, BA Harringa, JL TI Electrical and thermal properties of hot pressed (Nd0.5Gd0.5)Se1.50-x, where x=0.01, 0.02 SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Rare earth selenides, based on the composition (Nd0.5Gd0.5)Se1.50-x where 0.005 less than or equal tox less than or equal to0.030, were prepared by vapor phase reaction, melting, and hot pressing. The transport properties of electrical resistivity, Seebeck coefficient, and thermal diffusivity were characterized between 300 and 1300 K. In addition, carrier concentration and mobility were measured at 300 K. Chemical composition and homogeneity were determined on several samples by electron microprobe and atomic emission spectroscopy. Partial substitution of Nd for Gd was found to stabilize the high temperature gamma (Th3P4-type) phase. This system is characterized by a low thermal conductivity, the temperature dependence of which indicates mixed scattering. Analysis of the Seebeck and carrier concentration data by a single band conduction model suggests the existence of a heavy electron band, responsible for the large thermopower in this system. Electrical resistivity and Seebeck coefficient data were combined in a Jonker analysis to determine a maximum power factor, (S-2/rho), of 5.4 muW/cm degrees C2, corresponding to a resistivity of 5.5 Omega cm and a Seebeck coefficient of -172.3 muV/degreesC. (C) 2001 American Institute of Physics. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Cook, BA (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 25 TC 4 Z9 4 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 15 PY 2001 VL 90 IS 10 BP 5187 EP 5195 DI 10.1063/1.1412573 PG 9 WC Physics, Applied SC Physics GA 488CW UT WOS:000171918700047 ER PT J AU Balasubramanian, K Majumdar, D AF Balasubramanian, K Majumdar, D TI Spectroscopic properties of lead trimer (Pb-3 and Pb-3(+)): Potential energy surfaces, spin-orbit and Jahn-Teller effects SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SMALL SILICON CLUSTERS; LOW-LYING STATES; PHOTOELECTRON-SPECTROSCOPY; ELECTRONIC-STRUCTURE; DENSITY CALCULATIONS; INFRARED-SPECTRA; POSITIVE-IONS; TIN CLUSTERS; GERMANIUM; ANIONS AB Spectroscopic properties of the low-lying electronic states of neutral, cationic, and anionic lead trimer (Pb-3) are investigated. We have obtained the bending potential energy surfaces of several electronic states of Pb-3 and Pb-3(+) both with and without spin-orbit coupling. These computations were carried out using high level techniques that included electron correlation effects and spin-orbit coupling simultaneously using a multireference relativistic configuration interaction (RCI) scheme in the double group, subsequent to complete active-space-multiconfiguration self-consistent-field (CAS-MCSCF) computations. We have computed the equilibrium geometries, vibrational frequencies, excitation energies, atomization energies, ionization potentials, and adiabatic electron affinities. Our computations facilitated the assignment of the anion photodetachment spectra of Pb-3(-) and explained the "closed-shell singlet like" structures in the observed photodetachment spectra. Our computations show that spin-orbit coupling has a substantial impact on the geometries (bond angles changing up to 20 degrees) and the potential energy surfaces, which exhibit multiple minima separated by barriers due to avoided crossings and substantial spin-orbit mixings. The interplay between the Jahn-Teller effect and spin-orbit coupling was considered, and it was shown that the Jahn-Teller coupling is quenched by spin-orbit effect for Pb-3(+), but for the neutral trimer the bending potential energy surface of the ground state exhibits multiple minima due to a combination of these effects. The spin-orbit effect was also shown to reduce the strength of the Pb-Pb bonding and the atomization energy of Pb-3. Our computed atomization energy of Pb-3 including spin-orbit coupling is 224 KJ/mole in full agreement with the experimental value of 224 KJ/mole. We have shown that the spin-orbit coupling enhances the stability of Pb-3(+) while it weakens Pb-3 dramatically compared to lighter analogs such as Si-3. (C) 2001 American Institute of Physics. C1 Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, Berkeley, CA 94720 USA. RP Balasubramanian, K (reprint author), Univ Calif Davis, Dept Appl Sci, Hertz Hall,L-794, Livermore, CA 94550 USA. NR 66 TC 22 Z9 23 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 15 PY 2001 VL 115 IS 19 BP 8795 EP 8809 DI 10.1063/1.1412000 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 489PF UT WOS:000171999600008 ER PT J AU Balasubramanian, K Zhu, XL AF Balasubramanian, K Zhu, XL TI Spectroscopic properties of mixed gallium arsenide tetramers: GaAs3 +/-, GaAs3, Ga3As +/-, and Ga3As SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID KINETIC-ENERGY SPECTROSCOPY; INDIUM-PHOSPHIDE CLUSTERS; ANION PHOTOELECTRON-SPECTROSCOPY; LYING ELECTRONIC STATES; POSITIVE-IONS; CONFIGURATION-INTERACTION; INFRARED-SPECTRA; CONSTANTS; SURFACES; TRIMERS AB Spectroscopic properties of the low-lying electronic states of Ga3As, As3Ga, and their anions and cations are computed by the complete active-space self-consistent field (CASSCF) followed by multireference singles+doubles configuration interaction (MRSDCI) calculations that included up to 4.4 million configurations. Whereas the ground state of Ga3As is found to be a symmetric triangular pyramidal (C-3v) (1)A(1) structure, the ground state of As3Ga is predicted to undergo Jahn-Teller distortion to a C-s (1)A(') state with a folded geometry. The ground state of the Ga3As- ion is found to be surprisingly a planar (C-2v) structure but the ground state of the GaAs3- ion exhibits a C-s nonplanar Jahn-Teller distorted geometry. The energy separations of a number of excited electronic states have been computed to predict the spectra of these species. The equilibrium geometries, vibrational frequencies, atomization energies, adiabatic ionization potentials, electron affinities, and other properties for the electronic states of Ga3As and As3Ga are computed and discussed. Large differences in the equilibrium geometries of the Ga3As- anion and the neutral Ga3As are predicted to result in considerable vibrational progression the anion photoelectron spectra. (C) 2001 American Institute of Physics. C1 Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, Berkeley, CA 94720 USA. RP Balasubramanian, K (reprint author), Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. NR 60 TC 27 Z9 28 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 15 PY 2001 VL 115 IS 19 BP 8858 EP 8867 DI 10.1063/1.1412469 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 489PF UT WOS:000171999600014 ER PT J AU Weiss, J Hauschildt, J Schinke, R Haan, O Skokov, S Bowman, JM Mandelshtam, VA Peterson, KA AF Weiss, J Hauschildt, J Schinke, R Haan, O Skokov, S Bowman, JM Mandelshtam, VA Peterson, KA TI The unimolecular dissociation of the OH stretching states of HOCl: Comparison with experimental data SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID POTENTIAL-ENERGY SURFACE; RECURSION POLYNOMIAL EXPANSION; ABSORBING BOUNDARY-CONDITIONS; FILTER-DIAGONALIZATION; ANGULAR-MOMENTUM; GREENS-FUNCTION; NEAR-THRESHOLD; RESONANCES; DYNAMICS; HCO AB The unimolecular dissociation of the (v(1),0,0) pure OH stretching states of hypochlorous acid (HOCl) in the ground electronic state is investigated for v(1)=6-9. The dynamics calculations are performed on an accurate potential energy surface and employ filter diagonalization in connection with an imaginary absorbing potential. The dependence of the linewidth (or dissociation rate) on the total angular momentum is emphasized. Resonance enhancements due to mixings with other vibrational states, which have substantially larger rates, are clearly observed-in qualitative agreement with recent measurements. The average width increases, in quantitative agreement with experiments, by four orders of magnitude, from 10(-4) cm(-1) for v(1)=6 to about 1 cm(-1) for v(1)=9. (C) 2001 American Institute of Physics. C1 Max Planck Inst Stromungsforsch, D-37073 Gottingen, Germany. Gesell Wissensch Datenverarbeitung Gottingen, D-37077 Gottingen, Germany. Emory Univ, Dept Chem, Atlanta, GA 30322 USA. Emory Univ, Cherry L Emerson Ctr Sci Computat, Atlanta, GA 30322 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. Washington State Univ, Dept Chem, Richland, WA 99352 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Weiss, J (reprint author), Max Planck Inst Stromungsforsch, D-37073 Gottingen, Germany. NR 34 TC 16 Z9 16 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 15 PY 2001 VL 115 IS 19 BP 8880 EP 8887 DI 10.1063/1.1412602 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 489PF UT WOS:000171999600017 ER PT J AU Eliason, DE Bourgeois, AJ AF Eliason, DE Bourgeois, AJ TI An analytical solution for stratified tidal lagoons: Application to the validation of a numerical open boundary condition SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article AB An analytical solution is presented for the case of a stratified, tidally forced lagoon. This solution, especially its energy and mass balances, is useful for the validation of numerical shallow water models under stratified, tidally forced conditions. The utility of the analytical solution for validation is demonstrated for a simple finite difference numerical model. The energy, mass, and their balances from the numerical model are shown to converge to the analytical solution with a power law dependence as spatial and temporal resolution are increased. The power law convergence of the numerical results to the analytical solution validates both the finite difference scheme and the open boundary conditions used for the tidal forcing. The open boundary conditions work well because they are consistent with the characteristics of the analytical solution. C1 Lawrence Livermore Natl Lab, Div Atmospher Sci, Livermore, CA 94551 USA. Natl Ctr Atmospher Res, Mesoscale & Microscale Meteorol Div, Boulder, CO 80307 USA. RP Eliason, DE (reprint author), Lawrence Livermore Natl Lab, Div Atmospher Sci, L-103,POB 808, Livermore, CA 94551 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD NOV 15 PY 2001 VL 106 IS C11 BP 27061 EP 27076 DI 10.1029/2000JC000388 PG 16 WC Oceanography SC Oceanography GA 491JM UT WOS:000172105300018 ER PT J AU Vasco, DW Karasaki, K AF Vasco, DW Karasaki, K TI Inversion of pressure observations: an integral formulation SO JOURNAL OF HYDROLOGY LA English DT Article DE inverse problem; integral formulation; pressure tests ID GROUNDWATER-FLOW; PARAMETER-IDENTIFICATION; SOLUTE TRANSPORT; MODELS; CONDUCTIVITY; RELIABILITY; UNCERTAINTY; SYSTEMS; TIME AB It is possible to express the inverse problem for flow in an integral form. The integral formulation affords some insight concerning the recovery of subsurface flow properties. In particular, we find that rapid or high frequency variations in head are primarily sensitive to the specific storage. Conversely, slow or low frequency variations are most strongly influenced by hydraulic conductivity. The nonlinearity of the inverse problem is due to the presence of product terms in which the head field, or its gradient, multiplies a term dependent on flow properties. Thus, in their discrete form, the equations describing the inverse problem are algebraic. The integral formulation provides an alternative approach to linearizing the inverse problem, the Born approximation. We apply the methodology to data from a set of crosswell pressure tests conducted at the Raymond field site. We are able to image two fracture zones within the granitic subsurface. The location of these zones agrees with results from crosswell seismic tomography and borehole logging. Published by Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Vasco, DW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, 1 Cyclotron Rd,Mailstop 90-1116, Berkeley, CA 94720 USA. RI Vasco, Donald/I-3167-2016 OI Vasco, Donald/0000-0003-1210-8628 NR 52 TC 18 Z9 18 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD NOV 15 PY 2001 VL 253 IS 1-4 BP 27 EP 40 DI 10.1016/S0022-1694(01)00482-6 PG 14 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 486VH UT WOS:000171837300003 ER PT J AU Xu, QH Fleming, GR AF Xu, QH Fleming, GR TI Isomerization dynamics of 1,1 '-diethyl-4,4 '-cyanine (1144C) studied by different third-order nonlinear spectroscopic measurements SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID POTENTIAL-ENERGY SURFACE; TRIPHENYL-METHANE DYES; BARRIERLESS ISOMERIZATION; FEMTOSECOND SPECTROSCOPY; TEMPERATURE-DEPENDENCE; STIMULATED-EMISSION; TORSIONAL DYNAMICS; SOLVATION DYNAMICS; WAVEPACKET MOTION; OPTICAL RESPONSE AB The isomerization of 1, 1-diethyl-4,4 ' -cyanine (1144C) in two solvents, ethanol and hexanol, was studied by three different third-order four-wave mixing techniques: three-pulse photon echo peak shift (3PEPS), transient grating (TG), and pump-probe (PP) to provide complimentary information on different aspects of the reaction dynamics. A double-sided Feynman diagram analysis was used to assist in the formulation of the kinetic behavior in the TG and PP signals. The ground-state recovery process can be described as a single exponential process which is dominated by the bond-twisting motion on the excited-state surface. The rate is strongly viscosity and temperature dependent. A larger yield of the isomer is obtained in less viscous solvents or with greater excess excitation energy. Apparently, contradictory wavelength-dependent decay behavior was found in the TG and PP signals. This can be understood by considering the different real and imaginary contributions to the signals from hot ground-state absorption and its subsequent recovery to the equilibrated state and from the product state. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Xu, Qing-Hua/B-1478-2013 OI Xu, Qing-Hua/0000-0002-4153-0767 NR 58 TC 31 Z9 32 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD NOV 15 PY 2001 VL 105 IS 45 BP 10187 EP 10195 DI 10.1021/jp011924r PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 493DE UT WOS:000172206100003 ER PT J AU Skodje, RT Davis, MJ AF Skodje, RT Davis, MJ TI Geometrical simplification of complex kinetic systems SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID LOW-DIMENSIONAL MANIFOLDS; STEADY-STATE; COMPOSITION SPACE; APPROXIMATIONS; EQUILIBRIUM; PICTURE AB The use of low-dimensional manifolds to simplify the description of complicated systems of kinetics equations is investigated. Many models exhibit a generic behavior, whereby kinetic trajectories rapidly approach a surface of much lower dimension than that of the full phase space of concentrations, and subsequently show slow relaxation to equilibrium restricted to the surface. Traditional methods, such as the quasi-steady-state approximation, can be viewed as approximate schemes to construct the low dimensional manifolds., A number of techniques for the construction of low-dimensional manifolds are discussed and compared. A more general formulation of several previous methods is provided. A new technique, the global eigenvalue method, is derived. This method combines the conceptual advantages of the Maas-Pope algorithm with the accuracy of global trajectory propagation. One- and two-dimensional manifolds are constructed using the global eigenvalue method for a 38-reaction mechanism for hydrogen combustion. A new formulation of sensitivity analysis is provided which allows testing a reduced mechanism to changes in the rate constants. C1 Univ Colorado, Dept Chem, Boulder, CO 80309 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Skodje, RT (reprint author), Univ Colorado, Dept Chem, Boulder, CO 80309 USA. NR 28 TC 42 Z9 42 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD NOV 15 PY 2001 VL 105 IS 45 BP 10356 EP 10365 DI 10.1021/jp0108465 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 493DE UT WOS:000172206100024 ER PT J AU Khaliullin, RZ Bell, AT Kazansky, VB AF Khaliullin, RZ Bell, AT Kazansky, VB TI An experimental and density functional theory study of the interactions of CH4 with H-ZSM-5 SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID INITIO EMBEDDED-CLUSTER; INTERATOMIC POTENTIAL FUNCTION; AB-INITIO; METHANE MOLECULE; CARBON-MONOXIDE; ELECTRIC-FIELD; INFRARED-ANALYSIS; ZEOLITE ZSM-5; NAA ZEOLITE; ADSORPTION AB The interactions of methane with Bronsted acid sites in H-ZSM-5 were investigated both experimentally and theoretically. Diffuse reflectance infrared spectroscopy was used to acquire spectra for methane adsorbed on H-ZSM-5 at room temperature and at 77 K. Upon adsorption, the nu (1) and nu (3) vibrational bands of methane shift by -15 and -23 cm(-1), respectively, and the vibrational band for OH groups associated with Bronsted acid sites shifts by -93 cm(-1). Quantum chemical calculations conducted at the DFT level of theory with a 6-31g**++ basis set show that the observed shifts for methane are attributable to the effects of the electrostatic field created by the atoms of the zeolite. To represent the influence of the zeolite on the adsorbed methane correctly, it is essential to take into account the effects of the Madelung field, as well as the local effects of the acid center. The calculated shift in the vibrational frequency of the bridging OH group lies within the range observed experimentally. However, the quantitative agreement of the calculated and observed shift is not as good as that seen for the bands of CH4. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Russian Acad Sci, ND Zelinsky Organ Chem Inst, Moscow 117913, Russia. RP Bell, AT (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. EM bell@cchem.berkeley.edu; vbk@ioc.ac.ru RI Khaliullin, Rustam/B-2672-2009 OI Khaliullin, Rustam/0000-0002-9073-6753 NR 40 TC 40 Z9 40 U1 0 U2 15 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 NOV 15 PY 2001 VL 105 IS 45 BP 10454 EP 10461 DI 10.1021/jp012377c PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 493DE UT WOS:000172206100037 ER PT J AU Wang, XB Vorpagel, ER Yang, X Wang, LS AF Wang, XB Vorpagel, ER Yang, X Wang, LS TI Experimental and theoretical investigations of the stability, energetics, and structures, of H2PO4-, H2P2O72-, and H3P3O102- in the gas phase SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID MULTIPLY-CHARGED ANIONS; AB-INITIO; PHOTOELECTRON-SPECTROSCOPY; HYDROLYSIS; PHOTODETACHMENT; ORTHOPHOSPHATE; PYROPHOSPHATES; METAPHOSPHATE; 5'-PHOSPHATE; (HO)(2)PO2 AB The stability, energetics, and structures of three common inorganic phosphate species, H2PO4-, H2P2O72-, H3P3O102-, and their corresponding neutral radical and monoanions, were investigated in the gas phase using photodetachment photoelectron spectroscopy and theoretical calculations. We found that H2P2O72- and H3P3O102-. are stable in the gas phase with adiabatic electron binding energies of 1.16 and 2.45 eV, respectively. A very high adiabatic electron binding energy of 4.57 eV was measured for H2PO4-. The intramolecular Coulomb repulsion energies in H2P2O72- (similar to2.7 eV) and H3P3O102- (similar to2.3 eV) were estimated from photon-energy-dependent photoelectron spectra. Density-functional theory calculations were used to search the optimal geometries for both the doubly and singly charged species. We found only one minimum energy conformation for H2P2O72- with two intramolecular H-bonds and C-2 symmetry and three minimum energy structures for, H3P3O102-. The, lowest energy structure of H3P3O102- has three intramolecular H-bonds that do not share a common oxygen atom. The calculated electron detachment energy of H2PO4- agrees with the experimental value well, but the calculated detachment energies for H2P2O72- and H3P3O102- are similar to0.3 and similar to0.7 eV smaller than the experimental values, respectively. The observed spectral features, due to removal of electrons from lone-pair oxygen orbitals in the phosphate groups, were assigned qualitatively on the basis of the theoretical calculations. C1 Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, MSCF Visualizat & User Serv Grp, Richland, WA 99352 USA. RP Wang, LS (reprint author), Washington State Univ, Dept Phys, 2710 Univ Dr, Richland, WA 99352 USA. NR 25 TC 37 Z9 37 U1 0 U2 12 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 NOV 15 PY 2001 VL 105 IS 45 BP 10468 EP 10474 DI 10.1021/jp013244u PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 493DE UT WOS:000172206100039 ER PT J AU van de Lagemaat, J Frank, AJ AF van de Lagemaat, J Frank, AJ TI Nonthermalized electron transport in dye-sensitized nanocrystalline TiO2 films: Transient photocurrent and random-walk modeling studies SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SOLAR-CELLS; POTENTIAL DISTRIBUTION; NANOPOROUS TIO2; CHARGE-TRANSPORT; SINGLE-CRYSTALS; BACK-REACTION; ANATASE TIO2; POROUS TIO2; SPECTROSCOPY; KINETICS AB A random-walk approach is developed to model the electron-transport dynamics in dye-sensitized TiO2 Solar cells within a multiple-trapping framework, and the predicted results are compared with those measured by transient photocurrent. The illumination geometry and the wavelength of the probe light are used to create certain initial spatial distributions of photoinjected electrons in the TiO2 films. Both have a dramatic effect on the shape of the measured photocurrent transient. Cells are probed with light incident from either the collecting (substrate) electrode side or the counter-electrode side. Excellent correspondence between simulated and measured current transients is observed. When electrons are injected far from the collecting electrode, their diffusion is found to be classical, corresponding to thermalized (nondispersive) transport. Nonthermalized (dispersive) electron transport is shown to be important when electrons are injected near the collecting electrode, which corresponds to the illumination condition under which the cell normally operates. For strongly absorbed light incident from the collecting electrode side, it is estimated that about 80% of injected electrons are collected before they are within 95% of complete thermalization. Failure to account for the presence of nonthermalized electrons is shown to be a major limitation of previous theories of electron transport. The total density of trap states is estimated to be relatively small, on the order of I trap per particle. The average detrapping time is on the order of 10 ns. When electrons are generated far from the collecting electrode, they undergo an average of about 10(6) trapping events before being collected. Analytical expressions are derived that relate the experimentally measured collection time to other parameters affecting transport (e.g., trap density, light intensity, film thickness, and free-electron mobility). Experimental evidence is presented for ambipolar diffusion. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP van de Lagemaat, J (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI van de Lagemaat, Jao/J-9431-2012 NR 47 TC 327 Z9 327 U1 2 U2 76 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 NOV 15 PY 2001 VL 105 IS 45 BP 11194 EP 11205 DI 10.1021/jp0118468 PG 12 WC Chemistry, Physical SC Chemistry GA 493DG UT WOS:000172206300019 ER PT J AU Thorn, RJ AF Thorn, RJ TI Resistivity of a superconductor: A search for the origin of superconductivity SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article AB The measurements of the variation of the resistivity with temperature in increments of 0.02 K for single crystals of YBa2CU3O6+x by Pomar et al. (Phys. Rev. B 1996-I, 53, 8245-8248) yield discriminating values and show that the resistivity approaches zero at 0 K asymptotically. These measurements, which can serve as a prototype, have been analyzed in terms of equations, generally applicable for any superconductor, that recognize this fact and that describe the conductivities of the normal state with scattering and of the super state for mixed-valent bipolarons having no scattering. These descriptions, together with a description of the diamagnetic transition as a shift in the chemical equilibrium between polarons and bipolarons, identify a rationale for searching for the origin of superconductivity. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Thorn, RJ (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 19 TC 2 Z9 2 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 NOV 15 PY 2001 VL 105 IS 45 BP 11251 EP 11255 DI 10.1021/jp0108770 PG 5 WC Chemistry, Physical SC Chemistry GA 493DG UT WOS:000172206300026 ER PT J AU Annis, BK Kim, MH Alamo, R Pyda, M AF Annis, BK Kim, MH Alamo, R Pyda, M TI Inelastic neutron scattering from isotactic polypropylene SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE boson peak; isotactic polypropylene; neutron scattering; polymer dynamics; poly(propylene) (PP); spectroscopy ID GLASS-FORMING POLYMERS; X-RAY-SCATTERING; POLYETHYLENE AB We used inelastic neutron scattering to probe the low-energy excitations in semicrystalline isotactic polypropylenes with different degrees of crystallinity. The contributions from the amorphous and crystalline regions to the total scattering intensity were extracted under the assumption of a weighted linear contribution of the two regions in a simplified two-phase system. The resulting intensity from the amorphous region showed a peak at 1.2 meV that was in good agreement with the previously determined boson peak characteristic of atactic polypropylene. The possibility of a contribution to the boson peak region by longitudinal acoustic mode modes that are characteristic of semicrystalline polymers and appear in the same low-frequency region is discussed. (C) 2001 John Wiley & Sons, Inc. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Florida Agr & Mech Univ Florida State Univ, Coll Engn, Dept Chem Engn, Tallahassee, FL 32310 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RP Annis, BK (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 30 TC 1 Z9 1 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 NOV 15 PY 2001 VL 39 IS 22 BP 2852 EP 2859 DI 10.1002/polb.10039 PG 8 WC Polymer Science SC Polymer Science GA 487BE UT WOS:000171853200013 ER PT J AU Ciraolo, MF Hanson, JC Grey, CP AF Ciraolo, MF Hanson, JC Grey, CP TI Solid-state rubidium exchange of zeolite NH4Y SO MICROPOROUS AND MESOPOROUS MATERIALS LA English DT Article DE Na-23 and Rb-87 MAS NMR; in situ X-ray diffraction; ion exchange; faujasites ID MAS NMR; POWDER DIFFRACTION; NEUTRON-DIFFRACTION; QUADRUPOLAR NUCLEI; CENTRAL TRANSITION; CATION MIGRATION; X-ZEOLITE; RB-87 NMR; Y-ZEOLITE; ADSORPTION AB NH4Y has been ion exchanged by reaction with solid Rb2CO3 to form RbY. This process has been followed with X-ray powder diffraction, mass spectrometry and NMR. Both H-1 and Rb-87 MAS NMR are very sensitive to the hydration level of the zeolite and have been used to investigate the solid-state exchange process. Rb-87 NMR shows that exchange begins instantaneously on grinding the two solids together: decomposition of Rb2CO3 is observed, together with the migration of Rb+ into the zeolite pores. X-ray diffraction indicates that the reaction proceeds to completion by 400 degreesC. The structure of the final RbY product has been refined with Rietveld analysis and rubidium cations have been located at the SI' SII and SIII' positions. Residual sodium cations from the incomplete exchange of the ammonium starting material have been located at the SI position; this result was confirmed by Na-23 MAS NMR. No evidence for Rb occupation of the Sl positions was observed. Considerable disorder is observed in the cages of the zeolite during the ion-exchange process, but refinements of the structures, using the in situ data, indicate that Rb+ cations have entered the socialite cages by 200 degreesC. (C) 2001 Published by Elsevier Science B.V. C1 SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Grey, CP (reprint author), SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. RI Hanson, jonathan/E-3517-2010 NR 35 TC 10 Z9 10 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-1811 J9 MICROPOR MESOPOR MAT JI Microporous Mesoporous Mat. PD NOV 15 PY 2001 VL 49 IS 1-3 BP 111 EP 124 DI 10.1016/S1387-1811(01)00409-7 PG 14 WC Chemistry, Applied; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 491CM UT WOS:000172090500011 ER PT J AU Yang, ZY Zhu, QW Luo, KX Zhou, Q AF Yang, ZY Zhu, QW Luo, KX Zhou, Q TI The 7SK small nuclear RNA inhibits the CDK9/cyclin T1 kinase to control transcription SO NATURE LA English DT Article ID IMMUNODEFICIENCY-VIRUS TYPE-1; P-TEFB; TERMINAL DOMAIN; POLYMERASE-II; HIV-1 TAT; ELONGATION; ACTIVATION; PROMOTER; PHOSPHORYLATION; MECHANISM AB The human positive transcription elongation factor P-TEFb, consisting of a CDK9/cyclin T1 heterodimer, functions as both a general and an HIV-1 Tat-specific transcription factor(1,2). P-TEFb activates transcription by phosphorylating RNA polymerase (Pol) II, leading to the formation of processive elongation complexes. As a Tat cofactor, P-TEFb stimulates HIV-1 transcription by interacting with Tat and the transactivating responsive (TAR) RNA structure located at the 5' end of the nascent viral transcript(3). Here we identified 7SK, an abundant and evolutionarily conserved small nuclear RNA (snRNA) of unknown function(4,5), as a specific P-TEFb-associated factor. 7SK inhibits general and HIV-1 Tat-specific transcriptional activities of P-TEFb in vivo and in vitro by inhibiting the kinase activity of CDK9 and preventing recruitment of P-TEFb to the HIV-1 promoter. 7SK is efficiently dissociated from P-TEFb by treatment of cells with ultraviolet irradiation and actinomycin D. As these two agents have been shown to significantly enhance HIV-1 transcription and phosphorylation of Pol II (refs 6-8), our data provide a mechanistic explanation for their stimulatory effects. The 7SK/P-TEFb interaction may serve as a principal control point for the induction of cellular and HIV-1 viral gene expression during stress-related responses. Our studies demonstrate the involvement of an snRNA in controlling the activity of a Cdk-cyclin kinase. C1 Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Zhou, Q (reprint author), Univ Calif Berkeley, Dept Mol & Cell Biol, 229 Stanley Hall, Berkeley, CA 94720 USA. RI Yang, Zhiyuan/C-9543-2012 OI Yang, Zhiyuan/0000-0002-1175-4188 NR 24 TC 398 Z9 414 U1 5 U2 11 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD NOV 15 PY 2001 VL 414 IS 6861 BP 317 EP 322 DI 10.1038/35104575 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 492CM UT WOS:000172150700046 PM 11713532 ER PT J AU Dresselhaus, MS Thomas, IL AF Dresselhaus, MS Thomas, IL TI Alternative energy technologies SO NATURE LA English DT Article ID SEMICONDUCTOR ALLOYS AB Fossil fuels currently supply most of the world's energy needs, and however unacceptable their long-term consequences, the supplies are likely to remain adequate for the next few generations. Scientists and policy makers must make use of this period of grace to assess alternative sources of energy and determine what is scientifically possible, environmentally acceptable and technologically promising. C1 MIT, Cambridge, MA 02139 USA. US DOE, Off Basic Energy Sci, Germantown, MD 20874 USA. RP Dresselhaus, MS (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. NR 12 TC 1078 Z9 1106 U1 44 U2 332 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD NOV 15 PY 2001 VL 414 IS 6861 BP 332 EP 337 DI 10.1038/35104599 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 492CM UT WOS:000172150700052 PM 11713539 ER PT J AU Vitanov, NV Shore, BW Yatsenko, L Bohmer, K Halfmann, T Rickes, T Bergmann, K AF Vitanov, NV Shore, BW Yatsenko, L Bohmer, K Halfmann, T Rickes, T Bergmann, K TI Power broadening revisited: theory and experiment SO OPTICS COMMUNICATIONS LA English DT Article DE power broadening; line shape; pulsed excitation; adiabatic evolution ID COHERENT AB The spectral width of an atomic absorption line, observed with a steady light source, typically increases as the light intensity increases, an effect known as power broadening. In this paper, we point out classes of pulsed-light observations where power broadening does not always occur, We present analytical and numerical results, supported by experimental data of coherent pulsed excitation probed by photoionization, which show that the extent of power broadening depends crucially upon the nature of excitation and the type of measurement, In particular, we show that a spectral line obtained from measurement performed after pulsed excitation exhibits no power broadening. For pulsed excitation and continuous measurement, the spectral line contains two components: a power-broadened signal collected during the excitation and an unbroadened signal collected after the excitation. (C) 2001 Published by Elsevier Science B.V. C1 Univ Kaiserslautern, Fachbereich Phys, D-67653 Kaiserslautern, Germany. Univ Sofia, Dept Phys, BU-1126 Sofia, Bulgaria. Bulgarian Acad Sci, Inst Solid State Phys, BU-1784 Sofia, Bulgaria. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Ukrainian Acad Sci, Inst Phys, UA-252650 Kiev 22, Ukraine. RP Vitanov, NV (reprint author), Univ Helsinki, Helsinki Inst Phys, PL 9, FIN-00014 Helsinki, Finland. RI Vitanov, Nikolay/A-1248-2013; Halfmann, Thomas/O-4588-2014; BERGMANN, KLAAS/D-5543-2011; OI Halfmann, Thomas/0000-0002-1222-2669; Vitanov, Nikolay/0000-0002-8599-4766 NR 17 TC 46 Z9 47 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD NOV 15 PY 2001 VL 199 IS 1-4 BP 117 EP 126 DI 10.1016/S0030-4018(01)01495-X PG 10 WC Optics SC Optics GA 492PG UT WOS:000172176300014 ER PT J AU Bayindir, M Cubukcu, E Bulu, I Tut, T Ozbay, E Soukoulis, CM AF Bayindir, M Cubukcu, E Bulu, I Tut, T Ozbay, E Soukoulis, CM TI Photonic band gaps, defect characteristics, and waveguiding in two-dimensional disordered dielectric and metallic photonic crystals SO PHYSICAL REVIEW B LA English DT Article ID ELECTROMAGNETIC-WAVES; STRONG LOCALIZATION; IMPURITY BANDS; GUIDES; LIGHT; TRANSMISSION; PROPAGATION; MODES; MICROCAVITY; SPLITTERS AB We experimentally investigated the influence of positional disorder on the photonic band gap, defect characteristics, and waveguiding in two-dimensional dielectric and metallic photonic crystals. Transmission measurements performed on the dielectric photonic crystals have shown a stop band even if a large amount of disorder was introduced to these structures, On the other hand, the photonic band gap of the metallic crystals was found to be very sensitive to disorder, while the metallicity gap was not affected significantly. We addressed how the transmission characteristics of a cavity were affected in the presence of weak disorder. Since the translational symmetry was broken by disorders, we measured different cavity frequencies when we,generated defects at various locations. We also demonstrated the propagation of photons by hopping through coupled-cavity structures in both dielectric and metallic two-dimensional photonic crystals. Effects of weak disorder on guiding and bending of electromagnetic waves through the coupled-cavity waveguides were also investigated. C1 Bilkent Univ, Dept Phys, TR-06533 Ankara, Turkey. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. RP Bayindir, M (reprint author), Bilkent Univ, Dept Phys, TR-06533 Ankara, Turkey. EM bayindir@fen.bilkent.edu.tr RI Ozbay, Ekmel/B-9495-2008; Cubukcu, Ertugrul/F-4807-2010; bulu, irfan/E-5250-2011; Cubukcu, Ertugrul/D-5007-2012; Soukoulis, Costas/A-5295-2008 NR 53 TC 57 Z9 57 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 NOV 15 PY 2001 VL 64 IS 19 AR 195113 DI 10.1103/PhysRevB.64.195113 PG 7 WC Physics, Condensed Matter SC Physics GA 494WB UT WOS:000172307900047 ER PT J AU Chatraphorn, PP Toroczkai, Z Das Sarma, S AF Chatraphorn, PP Toroczkai, Z Das Sarma, S TI Epitaxial mounding in limited-mobility models of surface growth SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-BEAM EPITAXY; KINETIC GROWTH; EDGE DIFFUSION; NONEQUILIBRIUM GROWTH; NOISE-REDUCTION; DISCRETE MODELS; INSTABILITY; UNIVERSALITY; HOMOEPITAXY; CONTINUUM AB We study, through large-scale stochastic simulations using the noise reduction technique, surface growth via vapor deposition, e.g., molecular beam epitaxy (MBE), for simple nonequilibrium limited mobility solid-on-solid growth models, such as the Family model, the Das Sarma-Tamborenea model, the Wolf-Villain (WV) model, the larger-curvature (LC) model, and other related models. We find that (d=2+1)-dimensional surface growth in several noise reduced models (most notably the WV and LC models) exhibits spectacular quasiregular mound formation with slope selection in their dynamical surface morphology in contrast to the standard statistically scale-invariant kinetically rough surface growth expected (and earlier reported in the literature) for such growth models. The mounding instability in these epitaxial growth models does not involve the Ehrlich-Schwoebel step-edge diffusion barrier. The mounded morphology in these growth models arises from the interplay between the line tension along step edges in the plane parallel to the average surface and the suppression of noise and island nucleation. The line tension tends to stabilize some of the step orientations that coincide with in-plane high-symmetry crystalline directions, and thus the mounds that are formed assume quasiregular structures. The noise reduction technique developed originally for Eden-type models can be used to control the stochastic noise and enhance diffusion along the step edge, which ultimately leads to the formation of quasiregular mounds during growth. We show that by increasing the diffusion surface length together with supression of nucleation and deposition noise, one can obtain a self-organization of the pyramids in quasiregular patterns. The mounding instability in these simple epitaxial growth models is closely related to the cluster-edge diffusion (as opposed to step-edge barrier) driven mounding in MBE growth, which has been recently discussed in the literature. The epitaxial mound formation studied here is a kinetic-topological instability [which can happen only in (d=2+1) -dimensional, or higher dimensional, growth, but not in (d=1+1) -dimensional growth because no cluster diffusion around a closed surface loop is possible in "one-dimensional" surfaces], which is likely to be quite generic in real MBE-type surface growth. Our extensive numerical simulations produce mounded (and slope-selected) surface growth morphologies which are strikingly visually similar to many recently reported experimental MBE growth morphologies. C1 Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Chatraphorn, PP (reprint author), Chulalongkorn Univ, Fac Sci, Dept Phys, Bangkok 10330, Thailand. RI Toroczkai, Zoltan/A-3421-2008; Das Sarma, Sankar/B-2400-2009 OI Toroczkai, Zoltan/0000-0002-6602-2849; Das Sarma, Sankar/0000-0002-0439-986X NR 37 TC 25 Z9 26 U1 0 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 2001 VL 64 IS 20 AR 205407 DI 10.1103/PhysRevB.64.205407 PG 23 WC Physics, Condensed Matter SC Physics GA 497PL UT WOS:000172464600075 ER PT J AU Droubay, T Chambers, SA AF Droubay, T Chambers, SA TI Surface-sensitive Fe 2p photoemission spectra for alpha-Fe2O3(0001): The influence of symmetry and crystal-field strength SO PHYSICAL REVIEW B LA English DT Article ID TRANSITION-METAL COMPOUNDS; MOLECULAR-BEAM EPITAXY; PHOTOELECTRON-SPECTRA; ELECTRONIC-STRUCTURE; RAY; SPECTROSCOPY; GROWTH; ALPHA-AL2O3(0001); TERMINATION; SATELLITES AB We have measured high-energy-resolution Fe 2p photoelectron spectra for alpha -Fe2O3/alpha -Al2O3(0001) grown by oxygen-plasma-assisted molecular-beam epitaxy at emission angles chosen to enhance bulk and surface contributions. We quantitatively reproduce the subtle line-shape differences in these spectra by taking into account the break in symmetry and change in crystal field splitting generated by the presence of the surface. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Droubay, T (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Droubay, Tim/D-5395-2016 OI Droubay, Tim/0000-0002-8821-0322 NR 19 TC 49 Z9 49 U1 2 U2 12 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 NOV 15 PY 2001 VL 64 IS 20 AR 205414 DI 10.1103/PhysRevB.64.205414 PG 6 WC Physics, Condensed Matter SC Physics GA 497PL UT WOS:000172464600082 ER PT J AU Huang, ZB Lin, HQ Gubernatis, JE AF Huang, ZB Lin, HQ Gubernatis, JE TI Quantum Monte Carlo study of spin, charge, and pairing correlations in the t-t '-U Hubbard model SO PHYSICAL REVIEW B LA English DT Article ID FERMION GROUND-STATES; NEAREST-NEIGHBOR; NEUTRON-SCATTERING; U-T-T' MODEL; FLUCTUATIONS; ELECTRONS; DENSITY; PHASES; HOLE AB To clarify the effects of next-nearest-neighbor electron hopping t' on the spin, charge, and pairing correlations, we studied the two-dimensional t-t'-U Hubbard model using the constrained-path Monte Carlo technique. We found that a negative t' suppresses the spin fluctuations near the Brillouin zone point M = ( pi, pi) and the charge fluctuations near the point X = (pi ,0), while a positive t' has the opposite effect. For a negative t', we also found that the long-range vertex contributions to the pairing correlations are heavily suppressed, but the local contributions are enhanced. Over the entire hole doping range studied, the d-wave long-range vertex contributions to pairing dominated those of the extended s-wave vertex contributions. In general, we did not find any tendency for these correlations to grow with increasing system size. We also did a limited number of simulations with an attractive nearest neighbor density-density interaction added to the t-t'-U model. It enhanced the long-range vertex contributions to the pairing correlations only for weak values of U. C1 Chinese Univ Hong Kong, Dept Phys, Hong Kong, Hong Kong, Peoples R China. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87544 USA. RP Huang, ZB (reprint author), Chinese Univ Hong Kong, Dept Phys, Hong Kong, Hong Kong, Peoples R China. NR 32 TC 17 Z9 17 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 2001 VL 64 IS 20 AR 205101 DI 10.1103/PhysRevB.64.205101 PG 9 WC Physics, Condensed Matter SC Physics GA 497PL UT WOS:000172464600038 ER PT J AU Julien, JP Turchi, PEA Mayou, D AF Julien, JP Turchi, PEA Mayou, D TI Real-space solution of the coherent potential approximation equations in the Shiba approximation SO PHYSICAL REVIEW B LA English DT Article ID GENERALIZED PERTURBATION-THEORY; TIGHT-BINDING THEORY; BINARY-ALLOYS; ELECTRONIC-STRUCTURE; ORDERING ENERGIES; RECURSION METHOD; METAL-ALLOYS; STATES; DENSITY AB We present a generalization of a real-space method for solving the self-consistent field equations of the coherent potential approximation (CPA) for the case of multiplicative off-diagonal disorder originally proposed by Shiba. This generalization allows us to account for the difference in the bandwidths of the alloy-pure components in the study of the electronic properties of disordered alloys. The coherent potential and the Green function of the effective medium are expanded as continued fractions. It is shown that, contrary to the standard CPA method, the effective Hamiltonian is energy independent but acts in an augmented space, so that the recursion technique is directly applicable. This real-space approach opens up the possibility of studying the electronic structure properties of both chemically and topologically disordered alloys. Applications to the calculation of the density of states as well as to the study of stability of models and more realistic tight-binding Hamiltonians for binary transition-metal alloys are discussed. C1 Univ Polynesie Francaise, CUPF, Tahiti, Fr Polynesia. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. CNRS, LEPES, F-38042 Grenoble 9, France. RP Julien, JP (reprint author), Univ Polynesie Francaise, CUPF, BP 6570,Faaa Aeroport, Tahiti, Fr Polynesia. NR 44 TC 1 Z9 1 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 2001 VL 64 IS 19 AR 195119 PG 16 WC Physics, Condensed Matter SC Physics GA 494WB UT WOS:000172307900053 ER PT J AU Kim, YM Munteanu, FM Perry, CH Rickel, DG Simmons, JA Pfeiffer, LN West, KW AF Kim, YM Munteanu, FM Perry, CH Rickel, DG Simmons, JA Pfeiffer, LN West, KW TI Electron-hole separation studies near the nu=1 quantum Hall state in modulation-doped GaAs/(Al,Ga)As single heterojunctions in high magnetic fields SO PHYSICAL REVIEW B LA English DT Article ID ANYONIC IONS; PHOTOLUMINESCENCE; GAS; RECOMBINATION; EXCITONS; SPECTRA; LIQUID; MAGNETOOPTICS; SYSTEMS; INTEGER AB Magnetophotoluminescence (MPL) studies as a function of carrier concentration are reported for a series of very high mobility n-type modulation-doped GaAs/(Al,Ga)As single heterojunctions. The measurements were made in high magnetic fields to similar to 60 T and at temperatures in the 0.4-2.1 K range. At low fields (nu >2), the MPL recombination is dominated a free carrierlike excitonic transition as an energy close to the free exciton in bulk GaAs. The energy and intensity of this excitation undergoes Shubnikov-de Haas-type oscillations at even integer filling factors (nu> 2) with increasing field. At nu= 2(-), an second strong exciton transition appears at a lower energy primarily in sigma (-) polarization due to a spin up arrow electron recombining with a valence-band hole. It rapidly gains intensity between 2> nu> 1, but disappears at nu= 1(+). At nu= 1(-) another redshifted transition emerges that has been described as a recombination of an electron in an initial "free hole state." Its intensity in sigma (-) polarization increases and reaches a maximum between 1> nu >1/3. Such behavior becomes more pronounced as the carrier density increases. The redshift at nu= 1 has been correlated with recent theoretical models describing the theory of photoluminescence of two-dimensional electron systems. It has been used to determine the electron-hole separation as a function of carrier concentration. C1 Dankook Univ, Dept Appl Phys, Seoul, South Korea. Dongguk Univ, Quantum Funct Semicond Res Ctr, Seoul, South Korea. Veeco Instruments Inc, Longmont, CO 80501 USA. Northeastern Univ, Dept Phys, Boston, MA 02115 USA. Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. RP Kim, YM (reprint author), Dankook Univ, Dept Appl Phys, Seoul, South Korea. NR 31 TC 7 Z9 7 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 2001 VL 64 IS 19 AR 195302 DI 10.1103/PhysRevB.64.195302 PG 6 WC Physics, Condensed Matter SC Physics GA 494WB UT WOS:000172307900081 ER PT J AU Lyo, SK AF Lyo, SK TI Extreme magnetic modulation of the exciton transfer rate between unequal quantum wells SO PHYSICAL REVIEW B LA English DT Article ID ENERGY-TRANSFER; FIELDS AB We show that a moderate in-plane magnetic field quenches the Stokes transfer of excitons between direct and indirect (i.e., type II) quantum wells at low temperatures. The transfer is due to the decay of an exciton in the initial well into a free electron-hole pair in the final well. Higher fields open, within a narrow range of field, a new dramatically enhanced resonant transfer channel for both the Stokes and the anti-Stokes transfer between the higher-energy direct and lower-energy indirect exciton states. The rates are calculated for GaAs/AlxGa1-xAs quantum wells. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Lyo, SK (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 14 TC 5 Z9 5 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 2001 VL 64 IS 20 AR 201317 DI 10.1103/PhysRevB.64.201317 PG 4 WC Physics, Condensed Matter SC Physics GA 497PL UT WOS:000172464600025 ER PT J AU Ruhlander, M Markos, P Soukoulis, CM AF Ruhlander, M Markos, P Soukoulis, CM TI Probability distribution of the conductance in anisotropic systems SO PHYSICAL REVIEW B LA English DT Article ID METAL-INSULATOR-TRANSITION; DISORDERED-SYSTEMS; ANDERSON TRANSITION; SCALING PROPERTIES; MOBILITY EDGE; DIMENSIONAL CROSSOVER; MAGNETIC-FIELD; 2 DIMENSIONS; LOCALIZATION; UNIVERSALITY AB We investigate the probability distribution p(g) of the conductance g in anisotropic two-dimensional systems. The scaling procedure applicable to mapping the conductance distributions of localized anisotropic systems to the corresponding isotropic one can be extended to systems at the critical point of the metal-to-insulator transition. Instead of the squares used for isotropic systems, one should use rectangles for the anisotropic ones. At the critical point, the ratio of the side lengths must be equal to the square root of the ratio of the critical values of the quasi-one-dimensional scaling functions. For localized systems, the ratio of the side lengths must be equal to the ratio of the localization lengths. C1 Iowa State Univ, Ames Lab, Ames, IA 50012 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50012 USA. Slovak Acad Sci, Inst Phys, Bratislava 84228, Slovakia. RP Iowa State Univ, Ames Lab, Ames, IA 50012 USA. RI Soukoulis, Costas/A-5295-2008 NR 33 TC 3 Z9 3 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 NOV 15 PY 2001 VL 64 IS 19 AR 193103 PG 4 WC Physics, Condensed Matter SC Physics GA 494WB UT WOS:000172307900003 ER PT J AU von Zimmermann, M Nelson, CS Hill, JP Gibbs, D Blume, M Casa, D Keimer, B Murakami, Y Kao, CC Venkataraman, C Gog, T Tomioka, Y Tokura, Y AF von Zimmermann, M Nelson, CS Hill, JP Gibbs, D Blume, M Casa, D Keimer, B Murakami, Y Kao, CC Venkataraman, C Gog, T Tomioka, Y Tokura, Y TI X-ray resonant scattering studies of orbital and charge ordering in Pr1-xCaxMnO3 SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-DIFFRACTION; TRANSITION; MANGANITES; LAMNO3; LA0.5SR1.5MNO4; PR0.7CA0.3MNO3; MAGNETISM; STATE AB We present the results of a systematic x-ray scattering study of the charge and orbital ordering in the manganite series Pr1-xCaxMnO3 with x=0.25, 0.4, and 0.5. The temperature dependence of the scattering at the charge and orbital wavevectors, and of the lattice constants, was characterized throughout the ordered phase of each sample. It was found that the charge- and orbital-order wavevectors; are commensurate with the lattice, in striking contrast to the results of electron and neutron diffraction studies of samples with x=0.5. High-momentum-transfer resolution studies of the x=0.4 and 0.5 samples further revealed that while long-range charge order is present, long-range orbital order is never established. Above the charge and orbital ordering temperature To, the charge-order fluctuations are more highly correlated than the orbital fluctuations. This suggests that charge order drives orbital order in these samples. In addition, a longitudinal modulation of the lattice with the same periodicity as the charge and orbital ordering was discovered in the x=0.4 and 0.5 samples. For x=0.25, only long-range orbital order was observed with no indication of charge ordering, nor of an additional lattice modulation. We also report the results of a preliminary investigation of the loss of charge and orbital ordering in the x=0.4 sample by application of a magnetic field. Finally, the polarization and azimuthal dependence of the charge and orbital ordering in these compounds are characterized both in the resonant and nonresonant limits, and compared with the predictions of current theories. The results are qualitatively consistent with both cluster and local density approximation + U calculations of the electronic structure. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. High Energy Accelerator Res Org, Inst Mat Struct Sci, Photon Factory, Tsukuba, Ibaraki 3050801, Japan. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Argonne Natl Lab, Adv Photon Source, CMC CAT, Argonne, IL 60439 USA. JRCAT, Tsukuba, Ibaraki 3050033, Japan. Univ Tokyo, Dept Appl Phys, Tokyo 1130033, Japan. RP von Zimmermann, M (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Tokura, Yoshinori/C-7352-2009; Casa, Diego/F-9060-2016 NR 56 TC 52 Z9 52 U1 0 U2 9 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 NOV 15 PY 2001 VL 64 IS 19 AR 195133 PG 17 WC Physics, Condensed Matter SC Physics GA 494WB UT WOS:000172307900067 ER PT J AU Wang, LW AF Wang, LW TI Mask-function real-space implementations of nonlocal pseudopotentials SO PHYSICAL REVIEW B LA English DT Article ID TOTAL-ENERGY CALCULATIONS; FORMALISM AB A formalism is presented for the real-space implementation of the projector based nonlocal pseudopotentials in a plane wave density functional theory calculation. A unified mask function is used to truncate the projector in real space beyond a cutoff radius. About a thousandfold improvement in the accuracy can be achieved by the use of this mask function. Compared to previous methods. the current method does not need prefitting for each individual pseudopotential. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. NR 9 TC 12 Z9 12 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 2001 VL 64 IS 20 AR 201107 DI 10.1103/PhysRevB.64.201107 PG 4 WC Physics, Condensed Matter SC Physics GA 497PL UT WOS:000172464600007 ER PT J AU Wixom, RR Stringfellow, GB Modine, NA AF Wixom, RR Stringfellow, GB Modine, NA TI Theory of Sb-induced triple-period ordering in GaInP SO PHYSICAL REVIEW B LA English DT Article ID POLAR SEMICONDUCTOR SURFACES; TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; 2X2 RECONSTRUCTIONS; MOLECULAR-DYNAMICS; GAAS(100) SURFACES; ABINITIO THEORY; TRANSITION; GAAS(001); MODEL AB During organo-metallic vapor phase epitaxy (OMVPE) of GaInP (001) layers, the structure of the growth surface has a profound influence on the microstructure, and the optical and electrical properties of the resulting bulk material. The beta2 (2 x 4) surface, terminated with P dimers, provides a thermodynamic driving force for CuPtB ordering. Recently, surfactants such as Sb have been used to reduce this driving force. The use of surfactants to control the surface structure during growth has allowed for band-gap tailoring and the fabrication of heterostructures with no change in solid composition across the interface. Another exciting discovery was that high coverages of Sb induced a bulk triple period ordering. To further our understanding of these phenomena, the P terminated GaP(001) surface was studied via first principles calculations based on the Kohn-Sham density functional theory within the local density approximation (LDA). It was determined that under increasingly P-rich conditions, the beta2(2x4) and then the c(4x4) reconstructions are stable. When the surface is covered with Sb, several different reconstructions are found to be stable in the allowable range of chemical potentials. Under lower group-V coverages the beta2 (2x4) is stable, while at high Sb coverage, (4x3) and (2x3) reconstructions are stable. We propose that these (x3) reconstructions explain the triple period ordering seen in GaInP grown with Sb as a surfactant. Total-energy calculations confirm that (x3) reconstructions provide a thermodynamic driving force for A-variant triple period ordering. C1 Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wixom, RR (reprint author), Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. NR 33 TC 10 Z9 10 U1 1 U2 6 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 NOV 15 PY 2001 VL 64 IS 20 AR 201322 DI 10.1103/PhysRevB.64.201322 PG 4 WC Physics, Condensed Matter SC Physics GA 497PL UT WOS:000172464600030 ER PT J AU Xu, S Klimov, VI Kraabel, B Wang, H McBranch, DW AF Xu, S Klimov, VI Kraabel, B Wang, H McBranch, DW TI Femtosecond transient absorption study of oriented poly (9,9-dioctylfluorene) film: Hot carriers, excitons, and charged polarons SO PHYSICAL REVIEW B LA English DT Article ID PI-CONJUGATED OLIGOMERS; PHOTOEXCITATIONS; POLYACETYLENE; SPECTROSCOPY; TEMPERATURE; SOLITONS; EMISSION; DEFECTS; SPECTRA; DIODES AB We present a transient absorption spectroscopy study of oriented poly (9,9-dioctylfluorene) film. By comparing the spectral features and dynamics at different wavelengths using different probe polarizations, we conclude that three species are generated after the photoexcitation: hot carriers, excitons, and charged polarons. The charged polaron spectrum is measured with the probe beam polarized perpendicular to the polymer chains, and two bands are recognized. In addition, a new band in mid-IR regime is observed that decays faster than excitons, and whose peak shifts in time. This feature is assigned to hot carriers. C1 Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Xu, S (reprint author), Los Alamos Natl Lab, Chem Sci & Technol Div, CST-6, Los Alamos, NM 87545 USA. NR 30 TC 11 Z9 11 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 NOV 15 PY 2001 VL 64 IS 19 AR 193201 DI 10.1103/PhysRevB.64.193201 PG 4 WC Physics, Condensed Matter SC Physics GA 494WB UT WOS:000172307900004 ER PT J AU Zaliznyak, IA Tranquada, JM Erwin, R Moritomo, Y AF Zaliznyak, IA Tranquada, JM Erwin, R Moritomo, Y TI Spin-entropy-driven melting of the charge order in La1.5Sr0.5CoO4 SO PHYSICAL REVIEW B LA English DT Article ID PEROVSKITE COBALT OXIDES; MAGNETIC ORDER; STRIPE ORDER; TRANSITION; LA1.6-XND0.4SRXCUO4; SUPERCONDUCTIVITY; LA0.5SR1.5MNO4; FLUCTUATIONS; MANGANITES; PHYSICS AB We studied the melting of the charge order in the half-doped tetragonal perovskite La1.5Sr0.5CoO4 by elastic neutron scattering. We found that diffuse peaks, corresponding to the breathing-type modulation of oxygen positions in the CoO6 octahedra, disappear above T-c = 825(27) K. This melting of the diffuse superstructure is reversible (no change in the correlation lengths upon annealing is observed) and accompanied by a large nonlinear thermal expansion along the tetragonal c axis, with a cusp at T-c. We conclude that quenched disorder of the doped Sr ions is at the origin of this anisotropic charge glass state. We also suggest that its melting is driven by the transition from the intermediate- to the high-spin state of Co3+ ion, which is favored by the spin entropy at high T. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Nagoya Univ, CIRSE, Nagoya, Aichi 4648601, Japan. RP Zaliznyak, IA (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Tranquada, John/A-9832-2009; Zaliznyak, Igor/E-8532-2014 OI Tranquada, John/0000-0003-4984-8857; Zaliznyak, Igor/0000-0002-9886-3255 NR 21 TC 34 Z9 34 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 NOV 15 PY 2001 VL 64 IS 19 AR 195117 DI 10.1103/PhysRevB.64.195117 PG 4 WC Physics, Condensed Matter SC Physics GA 494WB UT WOS:000172307900051 ER PT J AU Zudov, MA Du, RR Simmons, JA Reno, JL AF Zudov, MA Du, RR Simmons, JA Reno, JL TI Shubnikov-de Haas-like oscillations in millimeterwave photoconductivity in a high-mobility two-dimensional electron gas SO PHYSICAL REVIEW B LA English DT Article ID CYCLOTRON-RESONANCE; HETEROSTRUCTURES; SYSTEM AB Millimeterwave photoconductivity in a high-mobility GaAs-AlxGa1-xAs two-dimensional electron gas exhibits giant amplitude oscillations in a weak magnetic field. These oscillations resemble the Shubnikov-de Haas effect but their period is determined by omega/omega (c), where omega and omega (c) are the millimeterwave and cyclotron frequencies. respectively. The major observations can be explained in terms of Landau-level transitions between spatially shifted oscillators. A 2k(F) Momentum transfer is accompanying the transition where k(F) is the electron Fermi wave number. C1 Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Zudov, MA (reprint author), Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. RI Zudov, Michael/A-3013-2008 NR 20 TC 312 Z9 313 U1 5 U2 18 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 15 PY 2001 VL 64 IS 20 AR 201311 DI 10.1103/PhysRevB.64.201311 PG 4 WC Physics, Condensed Matter SC Physics GA 497PL UT WOS:000172464600019 ER PT J AU Chalmers, G AF Chalmers, G TI Intermediate coupling regime in the AdS/CFT correspondence SO PHYSICAL REVIEW D LA English DT Article ID DE-SITTER SUPERGRAVITY; ADS-CFT CORRESPONDENCE; YANG-MILLS THEORY; STRING THEORY; GAUGE-THEORY; CORRELATORS; AMPLITUDES; INTEGRALS AB The correspondence between the 't Hooft limit of N=4 super Yang-Mills theory and tree-level type-IIB superstring theory on AdS(5) x S-5 in a Ramond-Ramond background at values of lambda = g(2)N ranging from infinity to zero is examined in the context of unitarity. A squaring relation for the imaginary part of the holographic scattering of identical string fields in the two-particle channels is found, and a mismatch between weak and strong 't Hooft coupling is pointed out within the correspondence. Several interpretations and implications are proposed. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. EM chalmers@pc19.hep.anl.gov NR 31 TC 0 Z9 0 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD NOV 15 PY 2001 VL 64 IS 10 AR 105022 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 490VH UT WOS:000172074100055 ER PT J AU Hill, CT Pokorski, S Wang, J AF Hill, CT Pokorski, S Wang, J TI Gauge invariant effective Lagrangian for Kaluza-Klein modes SO PHYSICAL REVIEW D LA English DT Article ID HIDDEN LOCAL SYMMETRIES; EXTRA DIMENSIONS; UNIFICATION; MILLIMETER; BREAKING; MESON; BOSON; MASS AB We construct a manifestly gauge invariant Lagrangian in 3 + 1 dimensions for N Kaluza-Klein modes of an SU(m) gauge theory in the bulk. For example, if the bulk is 4 + 1, the effective theory is Pi M+1i=1SU(m)(i) with N chiral ((m) over bar ,m) fields connecting the groups sequentially. This can be viewed as a Wilson action for a transverse lattice in x(5), and is shown explicitly to match the continuum 4 + 1 compactified Lagrangian truncated in momentum space. Scale dependence of the gauge couplings is described by the standard renormalization group technique with threshold matching, leading to effective power law running. We also discuss the unitarity constraints, and chiral fermions. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Inst Theoret Phys, PL-00681 Warsaw, Poland. RP Hill, CT (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM hill@fnal.gov; Stefan.Pokorski@fuw.edu.pl; jingw@fnal.gov NR 30 TC 292 Z9 292 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 15 PY 2001 VL 64 IS 10 AR 105005 DI 10.1103/PhysRevD.64.105005 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 490VH UT WOS:000172074100038 ER PT J AU Mazur, PO Mottola, E AF Mazur, PO Mottola, E TI Weyl cohomology and the effective action for conformal anomalies SO PHYSICAL REVIEW D LA English DT Article ID RENORMALIZATION-GROUP FLOW; ENERGY-MOMENTUM TENSOR; 4D QUANTUM-GRAVITY; CURVED SPACE-TIME; SCALAR CURVATURE; TRACE ANOMALIES; CENTRAL CHARGES; RANDOM SURFACES; DIMENSIONS; DIFFEOMORPHISMS AB We present a general method of deriving the effective action for conformal anomalies in any even dimension, which satisfies the Wess-Zumino consistency condition by construction. The method relies on defining the coboundary operator of the local Weyl group, g(ab)-->exp(2 sigma )g(ab), and giving a cohomological interpretation to counterterms in the effective action in dimensional regularization with respect to this group. Nontrivial cocycles of the Weyl group arise from local functionals that are Weyl invariant in and only in the physical even integer dimension d = 2k. In the physical dimension the nontrivial cocycles generate covariant nonlocal action functionals characterized by sensitivity to global Weyl rescalings. The nonlocal action so obtained is unique up to the addition of trivial cocycles and Weyl invariant terms, both of which are insensitive to global Weyl rescalings. These distinct behaviors under rigid dilations can be used to distinguish between infrared relevant and irrelevant operators in a generally covariant manner. Variation of the d = 4 nonlocal effective action yields two new conserved geometric stress tensors with local traces equal to the square of the Weyl tensor and the Gauss-Bonnet-Euler density, respectively. The second of these conserved tensors becomes H-(3)(ab) in conformally flat spaces, exposing the previously unsuspected origin of this tensor. The method may be extended to any even dimension by making use of the general construction of conformal invariants given by Fefferman and Graham. As a corollary, conformal field theory (CFT) behavior of correlators at the asymptotic infinity of either anti-de Sitter or de. Sitter spacetimes follows, i.e., AdS(d+1)- or deS(d+1)-CFTd correspondence. The same construction naturally selects all infrared relevant terms (and only those terms) in the low energy effective action of gravity in any even integer dimension. The infrared relevant terms arising from the known anomalies in d=4 imply that the classical Einstein theory is modified at large distances. C1 Univ S Carolina, Dept Phys & Astron, Columbia, SC 29208 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Univ S Carolina, Dept Phys & Astron, Columbia, SC 29208 USA. EM mazur@mail.psc.sc.edu; emil@lanl.gov OI Mazur, Pawel/0000-0002-1679-3637 NR 84 TC 108 Z9 108 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD NOV 15 PY 2001 VL 64 IS 10 AR 104022 DI 10.1103/PhysRevD.64.104022 PG 26 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 490VH UT WOS:000172074100033 ER PT J AU Amsler, C Baker, CA Barnett, BM Batty, CJ Benayoun, M Berdoz, A Blum, P Braune, K Case, T Crowe, KM Doser, M Dunnweber, W Engelhardt, D Faessler, MA Giarritta, P Haddock, RP Heinsius, FH Heinzelmann, M Hessey, NP Hidas, P Jamnik, D Kalinowsky, H Kammle, B Kammel, P Kisiel, J Klempt, E Koch, H Kunze, M Kurilla, U Lakata, M Landua, R Matthay, H Meyer, CA Meyer-Wildhagen, F Montanet, L Ouared, R Peters, K Pick, B Ratajczak, M Regenfus, C Roethel, W Seth, KK Strohbusch, U Suffert, M Suh, JS Thoma, U Uman, I Wallis-Plachner, S Walther, D Wiedner, U Wittmack, K Zupancic, C AF Amsler, C Baker, CA Barnett, BM Batty, CJ Benayoun, M Berdoz, A Blum, P Braune, K Case, T Crowe, KM Doser, M Dunnweber, W Engelhardt, D Faessler, MA Giarritta, P Haddock, RP Heinsius, FH Heinzelmann, M Hessey, NP Hidas, P Jamnik, D Kalinowsky, H Kammle, B Kammel, P Kisiel, J Klempt, E Koch, H Kunze, M Kurilla, U Lakata, M Landua, R Matthay, H Meyer, CA Meyer-Wildhagen, F Montanet, L Ouared, R Peters, K Pick, B Ratajczak, M Regenfus, C Roethel, W Seth, KK Strohbusch, U Suffert, M Suh, JS Thoma, U Uman, I Wallis-Plachner, S Walther, D Wiedner, U Wittmack, K Zupancic, C CA Crystal Barrel Collaboration TI A high resolution search for the tensor glueball candidate xi (2230) SO PHYSICS LETTERS B LA English DT Article ID J/PSI RADIATIVE DECAYS; CRYSTAL-BARREL; 11 GEV/C; STATES; GLUONS; MODEL; SPECTROSCOPY; RESONANCES; PI(0)PI(0); PBARP->K+K AB We report results of a high resolution search for the tensor glueball candidate xi (2230) in a (p) over barp formation experiment. pi (0)pi (0) and eta eta decay channels were measured in a scan of the mass region 2220 MeV to 2240 MeV. No evidence for the existence of xi (2230) was found. 95% confidence upper limits for the possible existence of xi are presented. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Zurich, CH-8057 Zurich, Switzerland. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. Univ Bonn, D-53115 Bonn, Germany. Hungarian Acad Sci, H-1525 Budapest, Hungary. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CERN, CH-1211 Geneva 4, Switzerland. Univ Hamburg, D-22761 Hamburg, Germany. Univ Karlsruhe, D-76021 Karlsruhe, Germany. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Munich, D-80333 Munich, Germany. LPNHE Paris 6, F-75252 Paris, France. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Ctr Rech Nucl, F-67037 Strasbourg, France. Northwestern Univ, Evanston, IL 60208 USA. RP Univ Zurich, CH-8057 Zurich, Switzerland. EM ulrich.wiedner@tsl.uu.se RI Peters, Klaus/C-2728-2008; Meyer, Curtis/L-3488-2014 OI Peters, Klaus/0000-0001-7133-0662; Meyer, Curtis/0000-0001-7599-3973 NR 37 TC 20 Z9 20 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 NOV 15 PY 2001 VL 520 IS 3-4 BP 175 EP 182 DI 10.1016/S0370-2693(01)01161-3 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 492EZ UT WOS:000172156600001 ER PT J AU Murayama, H Yanagida, T AF Murayama, H Yanagida, T TI LSND, SN1987A, and CPT violation SO PHYSICS LETTERS B LA English DT Article ID NEUTRINO OSCILLATIONS; SUPERNOVA 1987A; BURST; MASS; LIMITS; DECAY AB We point out that neutrino events observed at Kamiokande and IMB from SN1987A disfavor the neutrino oscillation parameters preferred by the LSND experiment. For Deltam(2) > 0 (the light side), the electron neutrinos from the neutronization burst would be lost, while the first event at Kamiokande is quite likely to be due to an electron neutrino. For Deltam(2) < 0 (the dark side), the average energy of the dominantly <(nu )over bar>(e) events is already lower than the theoretical expectations, which would 0 aet aggravated by a complete conversion from <()over bar>(mu) to <()over bar>(e). If taken seriously, the LSND data are disfavored independent of the existence of a sterile neutrino. A possible remedy is CPT violation, which allows different mass spectra for neutrinos and anti-neutrinos and hence can accommodate atmospheric, solar and LSND data without a sterile neutrino. If this is the case, Mini-BooNE must run in <()over bar> rather than the planned nu mode to test the LSND signal. We speculate on a possible origin of CPT violation. (C) 2001 Published by Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. Univ Tokyo, RESCEU, Bunkyo Ku, Tokyo 1130033, Japan. RP Murayama, H (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RI Yanagida, Tsutomu/A-4394-2011; Murayama, Hitoshi/A-4286-2011 NR 43 TC 128 Z9 130 U1 0 U2 2 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 NOV 15 PY 2001 VL 520 IS 3-4 BP 263 EP 268 DI 10.1016/S0370-2693(01)01136-4 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 492EZ UT WOS:000172156600012 ER PT J AU Baacke, J Cormier, D de Vega, HJ Heitmann, K AF Baacke, J Cormier, D de Vega, HJ Heitmann, K TI Dynamics of O (N) chiral supersymmetry at finite energy density SO PHYSICS LETTERS B LA English DT Article ID ELECTROWEAK PHASE-TRANSITION; SYMMETRY NON-RESTORATION; NONEQUILIBRIUM DYNAMICS; NONZERO TEMPERATURES; GOLDSTONE FERMION; MODEL; FIELD AB We consider an O(N) version of a massive, interacting, chiral supersymmetry model solved exactly in the large N limit. We demonstrate that the system approaches a stable attractor at high energy densities, corresponding to a non-perturbative state for which the relevant field quanta are massless. The state is one of spontaneously broken O(N), which, due to the influence of supersymmetry, does not become restored at high energies. Introducing soft supersymmetry breaking to the Lagrangian results in scalar masses at the soft breaking scale m(s) independent of the mass scale of supersymmetry mu, with even smaller masses for the fermions. (C) 2001 Published by Elsevier Science B.V. C1 Univ Dortmund, Inst Phys, D-44221 Dortmund, Germany. Univ Sussex, Ctr Theoret Phys, Brighton BN1 9QH, E Sussex, England. Univ Paris 06, Phys Theor & Hautes Energies Lab, F-75252 Paris, France. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Univ Dortmund, Inst Phys, D-44221 Dortmund, Germany. EM heitmann@lanl.gov NR 29 TC 2 Z9 2 U1 0 U2 0 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 NOV 15 PY 2001 VL 520 IS 3-4 BP 317 EP 321 DI 10.1016/S0370-2693(01)01168-6 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 492EZ UT WOS:000172156600019 ER PT J AU Balema, VP Wiench, JW Dennis, KW Pruski, M Pecharsky, VK AF Balema, VP Wiench, JW Dennis, KW Pruski, M Pecharsky, VK TI Titanium catalyzed solid-state transformations in LiAlH4 during high-energy ball-milling SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE lithium aluminum hydrides; mechanochemistry; solid state catalysis ID HYDROGEN STORAGE MATERIALS; SODIUM ALUMINUM-HYDRIDE; MECHANOCHEMICAL ACTIVATION; METAL HYDRIDES; AL-FE; TI-FE; LITHIUM; SYSTEM; DECOMPOSITION; PHASES AB Mechanical processing of polycrystalline LiAlH4 in the presence of titanium- and iron-based catalysts induces the transformation of LiAlH4 into Li(3)AIH(6), Al and H-2 at room temperature. Several catalysts were tested and it was established that their activity gradually decreases from TiCl4 to Fe in the series TiCl4 > Al3Ti much greater than Al22Fe3Ti8 > Al3Fe > Fe. The high catalytic activity of TiCl4 has been attributed to microcrystalline intermetallic Al3Ti, which rapidly forms in situ from TiCl4 and LiAlH4 during mechanical processing and then acts as a heterogeneous dehydrogenation catalyst. (C) 2001 Elsevier Science BY All rights reserved. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Pecharsky, VK (reprint author), Iowa State Univ Sci & Technol, Ames Lab, 242 Spedding, Ames, IA 50011 USA. NR 37 TC 166 Z9 169 U1 4 U2 32 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 NOV 14 PY 2001 VL 329 IS 1-2 BP 108 EP 114 DI 10.1016/S0925-8388(01)01570-5 PG 7 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 486KY UT WOS:000171818000019 ER PT J AU Choe, W Miller, GJ Levin, EM AF Choe, W Miller, GJ Levin, EM TI Crystal structure and magnetism of Gd2MgGe2 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE gadolinium; layered crystal structure; magnetization in dc and ac magnetic fields; anisotropic exchange interactions ID TRANSITION; GD-5(SI2GE2); GD-5(SI1.8GE2.2); HELIMAGNETISM; REFRIGERATION; SYSTEM; PHASES AB The title compound, Gd2MgGe2, crystallizes in a ternary variant of the tetragonal U3Si2 structure type with unit cell parameters of a=7.291(1) and c=4.2826(8) Angstrom, space group P4/mbm, Z=2. Temperature (4.3-300 K) and magnetic field (0-50 kOe) dependencies of the dc magnetization, along with temperature dependence of the ac magnetic susceptibility (25 Oe, 125 Hz) of Gd2MgGe2 are presented. The behavior of both the dc magnetization and ac magnetic susceptibility above ca. 150 K indicates a disordered magnetic state for Gd atoms while below ca. 150 K, it shows the existence of antiferromagnetic order. Tight-binding electronic structure (TB-LMTO-ASA) calculations including spin-polarization are utilized to discuss the chemical bonding and provide insights for the magnetic ordering process in this compound. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Miller, GJ (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RI Choe, Wonyoung/H-8495-2012 OI Choe, Wonyoung/0000-0003-0957-1187 NR 45 TC 40 Z9 40 U1 0 U2 2 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 NOV 14 PY 2001 VL 329 IS 1-2 BP 121 EP 130 DI 10.1016/S0925-8388(01)01568-7 PG 10 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 486KY UT WOS:000171818000021 ER PT J AU Li, JQ Tang, YL Shen, NF Pan, W AF Li, JQ Tang, YL Shen, NF Pan, W TI Effects of solidification kinetics on phase selection of Ni-Al alloys SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE transition metal alloys; high-temperature alloys; casting; rapid solidification; metallography ID RAPID SOLIDIFICATION; INTERMETALLIC COMPOUNDS; STABILITY; GROWTH; NI3AL AB Ni(x)A(100-x) (x=70, 75, 80at.%) alloys were obtained by planar flow casting. The phase selection behavior of the alloys under different processing conditions was studied by using X-ray diffraction and electron microscopy. In contrast to the conventional casting ingots, the volume fraction of gamma'-Ni3Al in the melt-spun ribbons increased and the volume fraction of beta -NiAl decreased. In the alloys Ni70Al30 and Ni75Al25, this trend is mainly due to the domination of the gamma' phase in the competition with the beta phase, caused by the higher kinetic undercooling of the gamma' phase during rapid solidification. The effects of melt quenching on the phase compositions were explained on the basis of the kinetic analyses of nucleation and dendrite growth of coexisting intermetallics gamma'(L1(2)) and beta (B2) phases. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Tsing Hua Univ, Dept Mat Sci & Engn, Beijing 100084, Peoples R China. Zhengzhou Univ Technol, Ctr Mat Res, Zhengzhou 450002, Peoples R China. RP Tang, YL (reprint author), Argonne Natl Lab, MSD223, Argonne, IL 60439 USA. NR 12 TC 8 Z9 10 U1 2 U2 8 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 NOV 14 PY 2001 VL 329 IS 1-2 BP 157 EP 161 DI 10.1016/S0925-8388(01)01573-0 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 486KY UT WOS:000171818000026 ER PT J AU Spanget-Larsen, J Gil, M Gorski, A Blake, DM Waluk, J Radziszewski, JG AF Spanget-Larsen, J Gil, M Gorski, A Blake, DM Waluk, J Radziszewski, JG TI Vibrations of the phenoxyl radical SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Review ID CORRELATED MOLECULAR CALCULATIONS; RESONANCE RAMAN-SPECTROSCOPY; ELECTRON-SPIN RESONANCE; AROMATIC AMINO-ACIDS; GAUSSIAN-BASIS SETS; GALACTOSE-OXIDASE; THERMAL-DECOMPOSITION; ACTIVE-SITE; AB-INITIO; UV SPECTRUM AB Phenoxyl radical (C6H5O) was prepared photochemically in low-temperature argon matrices. The infrared absorption spectra were obtained for C6H5O and for the isotopically labeled species C6D5O and 1-(CC5H5O)-C-13-C-12. All but one IR-active fundamental vibrations were detected, most of them not previously observed. Combination of results from IR linear dichroism measurements on photooriented samples, determination of absolute IR intensities with the help of internal standards, analysis of isotopic shifts, and quantum chemical predictions (B3LYP/cc-pVTZ) led to a detailed assignment of phenoxyl radical vibrations. Significant frequency shifts are observed with respect to previously reported data based on resonance Raman studies in polar solutions. For some vibrations, these shifts reflect environment-induced structural changes, such as increase of the quinoid character of the phenoxyl radical in polar media. In particular, the frequency of the CO stretching vibration, readily observable in both IR and Raman experiments, is extremely sensitive to the environment and can thus be used to probe its polarity. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA. Roskilde Univ Ctr, Dept Chem, DK-4000 Roskilde, Denmark. Polish Acad Sci, Inst Phys Chem, PL-01224 Warsaw, Poland. RP Radziszewski, JG (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Waluk, Jacek/C-8250-2011 NR 111 TC 44 Z9 44 U1 1 U2 24 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 NOV 14 PY 2001 VL 123 IS 45 BP 11253 EP 11261 DI 10.1021/ja0113596 PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 493TQ UT WOS:000172239900015 PM 11697968 ER PT J AU Bewley, MC Marohnic, CC Barber, MJ AF Bewley, MC Marohnic, CC Barber, MJ TI The structure and biochemistry of NADH-dependent cytochrome b(5) reductase are now consistent SO BIOCHEMISTRY LA English DT Article ID SITE-DIRECTED MUTAGENESIS; METHEMOGLOBINEMIA TYPE-I; RAT-LIVER MICROSOMES; B5 REDUCTASE; NADH-CYTOCHROME-B5 REDUCTASE; HEREDITARY METHEMOGLOBINEMIA; HUMAN-ERYTHROCYTES; NITRATE REDUCTASE; ELECTRON-TRANSFER; BINDING AB Cytochrome b(5) reductase (cb5r) (EC 1.6.6.2) catalyzes the reduction of two molecules of cytochrome b(5) using NADH as the physiological electron donor. The structure of pig cb5r at 2.4 Angstrom resolution was previously reported in the literature, but it was inconsistent with the biochemistry; for example, K83 and C245 were both implicated in the mechanism, but were not located at the active site. To address this problem, we have determined the structures of cb5r from rat at 2.0 Angstrom resolution and in a complex with NAD(+) at 2.3 Angstrom resolution. We found significant differences throughout the rat structure compared to that of pig, including the locations of the lysine and cysteine residues mentioned above. To test the structural models, we made single amino acid substitutions of this lysine and showed that all substitutions produced correctly folded proteins and exhibited normal flavin behavior. However, the apparent k(cat)(NADH) decreased, and the apparent Km for NADH increased; the K-m's for cytochrome b(5) were unchanged relative to that of the wild type. The largest effect was for the glutamate-substituted protein, which was further characterized using a charge transfer assay and found to be less efficient at NADH utilization than the wild type. These results are consistent with a role for this lysine in stabilizing the NADH-bound form of cb5r. We have concluded that the pig structure was mistraced in several regions and have reinterpreted mutants in these regions that give rise to the hereditary disease methemoglobinemia. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Univ S Florida, Coll Med, Dept Biochem & Mol Biol, Tampa, FL 33612 USA. Univ S Florida, Coll Med, H Lee Moffitt Canc Ctr & Res Inst, Tampa, FL 33612 USA. RP Bewley, MC (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. FU NIGMS NIH HHS [GM32696] NR 42 TC 52 Z9 53 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD NOV 13 PY 2001 VL 40 IS 45 BP 13574 EP 13582 DI 10.1021/bi0106336 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 493VP UT WOS:000172244400020 PM 11695905 ER PT J AU Gihring, TM Banfield, JF AF Gihring, TM Banfield, JF TI Arsenite oxidation and arsenate respiration by a new Thermus isolate SO FEMS MICROBIOLOGY LETTERS LA English DT Article DE arsenic; arsenite oxidation; arsenate respiration; Thermus; biogeochemistry ID GENERATION; MICROORGANISMS; SPECIATION; SEDIMENTS; REDUCTION; WATER; MINE; HPLC AB A new microbial strain was isolated from an arsenic-rich terrestrial geothermal environment. The isolate, designated HR13, was identified as a Thermus species based on 16S rDNA phylogenetic relationships and close sequence similarity within the Thermus genus. Under aerobic conditions, Thermus HR13 was capable of rapidly oxidizing inorganic As(III) to As(V). As(III) was oxidized at a rate approximately 100-fold greater than abiotic rates. Metabolic energy was not gained from the oxidation reaction. In the absence of oxygen, Thermus HR13 grew by As(V) respiration coupled with lactate oxidation. The ability to oxidize and reduce arsenic has not been previously described within the Thermus genus. (C) 2001 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved. C1 Univ Wisconsin, Dept Geol & Geophys, Madison, WI 53706 USA. RP Gihring, TM (reprint author), Pacif NW Natl Lab, POB 999,MS P7-50, Richland, WA 99352 USA. NR 30 TC 100 Z9 106 U1 2 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-1097 J9 FEMS MICROBIOL LETT JI FEMS Microbiol. Lett. PD NOV 13 PY 2001 VL 204 IS 2 BP 335 EP 340 DI 10.1111/j.1574-6968.2001.tb10907.x PG 6 WC Microbiology SC Microbiology GA 494NT UT WOS:000172289300020 PM 11731145 ER PT J AU Metzger, WK Wanlass, MW Ellingson, RJ Ahrenkiel, RK Carapella, JJ AF Metzger, WK Wanlass, MW Ellingson, RJ Ahrenkiel, RK Carapella, JJ TI Auger recombination in low-band-gap n-type InGaAs SO APPLIED PHYSICS LETTERS LA English DT Article ID SEMICONDUCTORS AB We measured the recombination lifetime of degenerate n-InxGa1-xAs for three different compositions that correspond to x=0.53, 0.66, and 0.78 (band gaps of 0.74, 0.60, and 0.50 eV, respectively) over the doping range of 3x10(18)-5x10(19) carriers/cm(3). The Auger recombination rate increases slowly with decreasing band gap, and it matches the behavior predicted for phonon-assisted recombination. (C) 2001 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Metzger, WK (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Ellingson, Randy/H-3424-2013 NR 21 TC 30 Z9 32 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 12 PY 2001 VL 79 IS 20 BP 3272 EP 3274 DI 10.1063/1.1418032 PG 3 WC Physics, Applied SC Physics GA 490HQ UT WOS:000172046800020 ER PT J AU Roberts, RG Romanino, A Ross, GG Velasco-Sevilla, L AF Roberts, RG Romanino, A Ross, GG Velasco-Sevilla, L TI Precision test of a Fermion mass texture SO NUCLEAR PHYSICS B LA English DT Article ID U(2) FLAVOR SYMMETRY; QUARK; PREDICTIONS; PARAMETER AB Texture zeros in the quark Yukawa matrices generally lead to precise and simple expressions for CKM matrix elements in terms of ratios of quark masses. Using the new data on b-decays we test a particularly promising texture zero solution and show that it is at best approximate. We analyse the approximate texture zero structure and show it is consistent with experiment. We investigate the implications for the CKM unitarity triangle, measurements at BaBar and BELLE as well as for the theories which invoke family symmetries. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Oxford, Dept Phys, Oxford OX1 3NP, England. RP Roberts, RG (reprint author), Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. RI Romanino, Andrea/I-3480-2012 OI Romanino, Andrea/0000-0002-5915-4747 NR 42 TC 101 Z9 101 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 NOV 12 PY 2001 VL 615 IS 1-3 BP 358 EP 384 DI 10.1016/S0550-3213(01)00408-4 PG 27 WC Physics, Particles & Fields SC Physics GA 489PV UT WOS:000172001200015 ER PT J AU Tellers, DM Bergman, RG AF Tellers, DM Bergman, RG TI An examination of C-H bond activation by cationic Tp(Me2)Ir(III) complexes SO ORGANOMETALLICS LA English DT Article ID CARBON-HYDROGEN; IRIDIUM(III) COMPLEXES; METAL-COMPLEXES; STRUCTURAL CHARACTERIZATION; ALKANE DEHYDROGENATION; REDUCTIVE ELIMINATION; OXIDATIVE ADDITION; DINITROGEN COMPLEX; TRANSITION-METALS; PINCER COMPLEX AB Synthesis and characterization of a set of iridium(III) compounds utilizing the sterically encumbering hydridotris(3,5-dimethylpyrazolyl)borate ligand (Tp(Me2)) has been performed, and a comparison with the corresponding Cp* complexes is presented. Tp(Me2)(PMe3)Ir(Me)-OTf (7, OTf = O3SCF3) was synthesized and found to be unreactive toward a variety of C-H bonds, in contrast to the behavior of Cp*(PMe3)Ir(Me)OTf (1). We have rationalized this lack of reactivity in terms of an electronic effect rather than a steric effect imposed by the Tp(Me2) ligand. Metathesis of the triflate ligand with the BArf (BArf = B[3,5-C6H3(CF3)(2)](4)) anion under a N-2 atmosphere produces the dinitrogen complex [Tp(Me2)(PMe3)Ir(N-2)(Me)][BArf] (3-N-2). Compound 3-N-2 is indeed reactive toward dative ligands, H-2, and hydrocarbons, activating the C-H bonds of benzene and aldehydes but not those of saturated hydrocarbons. A rationale for the difference in behavior between the Cp* and Tp(Me2) systems with respect to C-H activation is presented. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Bergman, RG (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 90 TC 63 Z9 63 U1 2 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD NOV 12 PY 2001 VL 20 IS 23 BP 4819 EP 4832 DI 10.1021/om010697c PG 14 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 493VB UT WOS:000172243200012 ER PT J AU Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Palano, A Chen, GP Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Reinertsen, PL Stugu, B Abbott, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Clark, AR Gill, MS Gritsan, A Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kluth, S Kolomensky, YG Kral, JF LeClerc, C Levi, ME Liu, T Lynch, G Meyer, AB Momayezi, M Oddone, PJ Perazzo, A Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Bright-Thomas, PG Harrison, TJ Hawkes, CM Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, 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Dorfan, J Doser, M Dunwoodie, W Field, RC Glanzman, T Godfrey, GL Gowdy, SJ Grosso, P Himel, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Moffeit, KC Mount, R Muller, DR O'Grady, CP Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Rochester, LS Roodman, A Schietinger, T Schindler, RH Schwiening, J Serbo, VV Snyder, A Soha, A Spanier, SM Stelzer, J Su, D Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, PR Cheng, CH Kirkby, D Meyer, TI Roat, C Henderson, R Bugg, W Cohn, H Weidemann, AW Izen, JM Kitayama, I Lou, XC Turcotte, M Bianchi, F Bona, M Di Girolamo, B Gamba, D Smol, A Zanin, D Lanceri, L Pompili, A Vuagnin, G Panvini, RS Brown, CM De Silva, A Kowalewski, R Roney, JM Band, HR Charles, E Dasu, S Di Lodovico, F Eichenbaum, AM Hu, H Johnson, JR Liu, R Nielsen, J Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, SL Yu, Z Zobernig, H Kordich, TMB Neal, H AF Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Palano, A Chen, GP Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Reinertsen, PL Stugu, B Abbott, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Clark, AR Gill, MS Gritsan, A Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kluth, S Kolomensky, YG Kral, JF LeClerc, C Levi, ME Liu, T Lynch, G Meyer, AB Momayezi, M Oddone, PJ Perazzo, A Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Bright-Thomas, PG Harrison, TJ Hawkes, CM Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, K Koch, H Krug, J Kunze, M Lewandowski, B Peters, K Schmuecker, H Steinke, M Andress, JC Barlow, NR Bhimji, W Chevalier, N Clark, PJ Cottingham, WN De Groot, N Dyce, N Foster, B McFall, JD Wallom, D Wilson, FF Abe, K Hearty, C Mattison, TS McKenna, JA Thiessen, D Jolly, S McKemey, AK Tinslay, J Blinov, VE Bukin, AD Bukin, DA Buzykaev, AR Golubev, VB Ivanchenko, VN Korol, AA Kravchenko, EA Onuchin, AP Salnikov, AA Serednyakov, SI Skovpen, YI Telnov, VI Yushkov, AN Best, D Lankford, AJ Mandelkern, M McMahon, S Stoker, DP Ahsan, A Arisaka, K Buchanan, C Chun, S Branson, JG MacFarlane, DB Prell, S Rahatlou, S Raven, G Sharma, V Campagnari, C Dahmes, B Hart, PA Kuznetsova, N Levy, SL Long, O Lu, A Richman, JD Verkerke, W Witherell, M Yellin, S Beringer, J Dorfan, DE Eisner, AM Frey, A Grillo, AA Grothe, M Heusch, CA Johnson, RP Kroeger, W Lockman, WS Pulliam, T Sadrozinski, H Schalk, T Schmitz, RE Schumm, BA Seiden, A Turri, M Walkowiak, W Williams, DC Wilson, MG Chen, E Dubois-Felsmann, GP Dvoretskii, A Hitlin, DG Metzler, S Oyang, J Porter, FC Ryd, A Samuel, A Weaver, M Yang, S Zhu, RY Devmal, S Geld, TL Jayatilleke, S Mancinelli, G Meadows, BT Sokoloff, MD Barillari, T Bloom, P Dima, MO Fahey, S Ford, WT Johnson, DR Nauenberg, U Olivas, A Park, H Rankin, P Roy, J Sen, S Smith, JG van Hoek, WC Wagner, DL Blouw, J Harton, JL Krishnamurthy, M Soffer, A Toki, WH Wilson, RJ Zhang, J Brandt, T Brose, J Colberg, T Dahlinger, G Dickopp, M Dubitzky, RS Maly, E Muller-Pfefferkorn, R Otto, S Schubert, KR Schwierz, R Spaan, B Wilden, L Behr, L Bernard, D Bonneaud, GR Brochard, F Cohen-Tanugi, J Ferrag, S Roussot, E T'Jampens, S Thiebaux, C Vasileiadis, G Verderi, M Anjomshoaa, A Bernet, R Khan, A Muheim, F Playfer, S Swain, JE Falbo, M Borean, C Bozzi, C Dittongo, S Folegani, M Piemontese, L Treadwell, E Anulli, F Baldini-Ferroli, R Calcaterra, A de Sangro, R Falciai, D Finocchiaro, G Patteri, P Peruzzi, IM Piccolo, M Xie, Y Zallo, A Bagnasco, S Buzzo, A Contri, R Crosetti, G Fabbricatore, P Farinon, S Lo Vetere, M Macri, M Monge, MR Musenich, R Pallavicini, M Parodi, R Passaggio, S Pastore, FC Patrignani, C Pia, MG Priano, C Robutti, E Santroni, A Morii, M Bartoldus, R Dignan, T Hamilton, R Mallik, U Cochran, J Crawley, HB Fischer, PA Lamsa, J Meyer, WT Rosenberg, EI Benkebil, M Grosdidier, G Hast, C Hocker, A Lacker, HM LePeltier, V Lutz, AM Plaszczynski, S Schune, MH Trincaz-Duvoid, S Valassi, A Wormser, G Bionta, RM Brigljevic, V Lange, DJ Mugge, M Shi, X van Bibber, K Wenaus, TJ Wright, DM Wuest, CR Carroll, M Fry, JR Gabathuler, E Gamet, R George, M Kay, M Payne, DJ Sloane, RJ Touramanis, C Aspinwall, ML Bowerman, DA Dauncey, PD Egede, U Eschrich, I Gunawardane, NJW Nash, JA Sanders, P Smith, D Azzopardi, DE Back, JJ Dixon, P Harrison, PF Potter, RJL Shorthouse, HW Strother, P Vidal, PB Williams, MI Cowan, G George, S Green, MG Kurup, A Marker, CE McGrath, P McMahon, TR Ricciardi, S Salvatore, F Scott, I Vaitsas, G Brown, D Davis, CL Allison, J Barlow, RJ Boyd, JT Forti, AC Fullwood, J Jackson, F Lafferty, GD Savvas, N Simopoulos, ET Weatherall, JH Farbin, A Jawahery, A Lillard, V Olsen, J Roberts, DA Schieck, JR Blaylock, G Dallapiccola, C Flood, KT Hertzbach, SS Kofler, R Moore, TB Staengle, H Willocq, S Brau, B Cowan, R Sciolla, G Taylor, F Yamamoto, RK Milek, M Patel, PM Trischuk, J Lanni, F Palombo, F Bauer, JM Booke, M Cremaldi, L Eschenburg, V Kroeger, R Reidy, J Sanders, DA Summers, DJ Martin, JP Nief, JY Seitz, R Taras, P Zacek, V Nicholson, H Sutton, CS Cartaro, C Cavallo, N De Nardo, G Fabozzi, F Gatto, C Lista, L Paolucci, P Piccolo, D Sciacca, C LoSecco, JM Alsmiller, JRG Gabriel, TA Handler, T Brau, J Frey, R Iwasaki, M Sinev, NB Strom, D Colecchia, F Dal Corso, F Dorigo, A Galeazzi, F Margoni, M Michelon, G Morandin, M Posocco, M Rotondo, M Simonetto, F Stroili, R Torassa, E Voci, C Benayoun, M Briand, H Chauveau, J David, P De la Vaissiere, C Del Buono, L Hamon, O Le Diberder, F Leruste, P Lory, J Roos, L Stark, J Versille, S Manfredi, PF Re, V Speziali, V Frank, ED Gladney, L Guo, QH Panetta, JH Angelini, C Batignani, G Bettarini, S Bondioli, M Carpinelli, M Forti, F Giorgi, MA Lusiani, A Martinez-Vidal, F Morganti, M Neri, N Paoloni, E Rama, M Rizzo, G Sandrelli, F Simi, G Triggiani, G Walsh, J Haire, M Judd, D Paick, K Turnbull, L Wagoner, DE Albert, J Bula, C Elmer, P Lu, C McDonald, KT Miftakov, V Schaffner, SF Smith, AJS Tumanov, A Varnes, EW Cavoto, G del Re, D Faccini, R Ferrarotto, F Ferroni, F Fratini, K Lamanna, E Leonardi, E Mazzoni, MA Morganti, S Piredda, G Tehrani, FS Serra, M Voena, C Christ, S Waldi, R Adye, T Franek, B Geddes, NI Gopal, GP Xella, SM Aleksan, R De Domenico, G Emery, S Gaidot, A Ganzhur, SF de Monchenault, GH Kozanecki, W Langer, M London, GW Mayer, B Serfass, B Vasseur, G Yeche, C Zito, M Copty, N Purohit, MV Singh, H Yumiceva, FX Adam, I Anthony, PL Aston, D Baird, K Bloom, E Boyarski, AM Bulos, F Calderini, G Claus, R Convery, MR Coupal, DP Coward, DH Dorfan, J Doser, M Dunwoodie, W Field, RC Glanzman, T Godfrey, GL Gowdy, SJ Grosso, P Himel, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Moffeit, KC Mount, R Muller, DR O'Grady, CP Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Rochester, LS Roodman, A Schietinger, T Schindler, RH Schwiening, J Serbo, VV Snyder, A Soha, A Spanier, SM Stelzer, J Su, D Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, PR Cheng, CH Kirkby, D Meyer, TI Roat, C Henderson, R Bugg, W Cohn, H Weidemann, AW Izen, JM Kitayama, I Lou, XC Turcotte, M Bianchi, F Bona, M Di Girolamo, B Gamba, D Smol, A Zanin, D Lanceri, L Pompili, A Vuagnin, G Panvini, RS Brown, CM De Silva, A Kowalewski, R Roney, JM Band, HR Charles, E Dasu, S Di Lodovico, F Eichenbaum, AM Hu, H Johnson, JR Liu, R Nielsen, J Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, SL Yu, Z Zobernig, H Kordich, TMB Neal, H CA BABAR Collaboration TI Measurement of the B-0 and B+ meson lifetimes with fully reconstructed hadronic final states SO PHYSICAL REVIEW LETTERS LA English DT Article AB The B-o and B+ meson lifetimes have been measured in e(+)e(-) annihilation data collected in 1999 and 2000 with the BABAR detector at center-of-mass energies near the Y(4S) resonance. 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Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Naples Federico 2, Dipartimento Sci Fis, I-80126 Naples, Italy. Ist Nazl Fis Nucl, I-80126 Naples, Italy. Univ Notre Dame, Notre Dame, IN 46556 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Padua, Dipartimento Fis, I-35131 Padua, Italy. Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Paris 06, LPNHE, F-75252 Paris, France. Univ Paris 07, LPNHE, F-75252 Paris, France. Univ Pavia, Dipartimento Fis, I-27100 Pavia, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Penn, Philadelphia, PA 19104 USA. Ist Nazl Fis Nucl, I-56010 Pisa, Italy. Univ Pisa, Scuola Normale Super Pisa, I-56010 Pisa, Italy. Prairie View A&M Univ, Prairie View, TX 77446 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Univ Rostock, D-18051 Rostock, Germany. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CEA, DAPNIA, F-91191 Gif Sur Yvette, France. Univ S Carolina, Columbia, SC 29208 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Stanford, CA 94305 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ Tennessee, Knoxville, TN 37996 USA. Univ Texas, Richardson, TX 75083 USA. Univ Turin, Dipartimento Fis Sperimentale, I-10125 Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Trieste, Dipartmento Fis, I-34127 Trieste, Italy. Ist Nazl Fis Nucl, I-34127 Trieste, Italy. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Victoria, Victoria, BC V8W 3P6, Canada. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. Iowa State Univ Sci & Technol, Ames, IA 50011 USA. RP Aubert, B (reprint author), Lab Phys Particules, F-74941 Annecy Le Vieux, France. RI Morandin, Mauro/A-3308-2016; Di Lodovico, Francesca/L-9109-2016; Martinez Vidal, F*/L-7563-2014; Lusiani, Alberto/A-3329-2016; Lusiani, Alberto/N-2976-2015; Calcaterra, Alessandro/P-5260-2015; Frey, Raymond/E-2830-2016; Telnov, Valery/C-6900-2009; Cavallo, Nicola/F-8913-2012; Patrignani, Claudia/C-5223-2009; Monge, Maria Roberta/G-9127-2012; Kravchenko, Evgeniy/F-5457-2015; Kolomensky, Yury/I-3510-2015; Lo Vetere, Maurizio/J-5049-2012; Lamanna, Ernesto/C-7658-2012; Pallavicini, Marco/G-5500-2012; de Groot, Nicolo/A-2675-2009; Lista, Luca/C-5719-2008; Schaffner, Stephen/D-1189-2011; Frank, Edward/A-8865-2012; Roe, Natalie/A-8798-2012; Pia, Maria Grazia/C-7034-2012; Torassa, Ezio/I-1788-2012; Forti, Francesco/H-3035-2011; Rotondo, Marcello/I-6043-2012; de Sangro, Riccardo/J-2901-2012; Valassi, Andrea/K-7506-2012; Peters, Klaus/C-2728-2008 OI Adye, Tim/0000-0003-0627-5059; Wilson, Robert/0000-0002-8184-4103; Wallom, David/0000-0001-7527-3407; Morandin, Mauro/0000-0003-4708-4240; Di Lodovico, Francesca/0000-0003-3952-2175; Martinez Vidal, F*/0000-0001-6841-6035; Lusiani, Alberto/0000-0002-6876-3288; Lusiani, Alberto/0000-0002-6876-3288; Calcaterra, Alessandro/0000-0003-2670-4826; Frey, Raymond/0000-0003-0341-2636; Carpinelli, Massimo/0000-0002-8205-930X; Watson, Nigel/0000-0002-8142-4678; Sciacca, Crisostomo/0000-0002-8412-4072; Nielsen, Jason/0000-0002-9175-4419; Telnov, Valery/0000-0002-8312-8119; Patrignani, Claudia/0000-0002-5882-1747; Monge, Maria Roberta/0000-0003-1633-3195; Kolomensky, Yury/0000-0001-8496-9975; Lo Vetere, Maurizio/0000-0002-6520-4480; Lamanna, Ernesto/0000-0002-7844-8230; Pallavicini, Marco/0000-0001-7309-3023; Pia, Maria Grazia/0000-0002-3579-9639; Forti, Francesco/0000-0001-6535-7965; Rotondo, Marcello/0000-0001-5704-6163; de Sangro, Riccardo/0000-0002-3808-5455; Valassi, Andrea/0000-0001-9322-9565; Peters, Klaus/0000-0001-7133-0662 NR 6 TC 24 Z9 24 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 NOV 12 PY 2001 VL 87 IS 20 AR 201803 DI 10.1103/PhysRevLett.87.201803 PG 7 WC Physics, Multidisciplinary SC Physics GA 492TD UT WOS:000172182900003 PM 11690464 ER PT J AU Clark, RM Fallon, P Gorgen, A Cromaz, M Deleplanque, MA Diamond, RM Lane, GJ Lee, IY Macchiavelli, AO Ramos, RG Stephens, FS Svensson, CE Vetter, K Ward, D Carpenter, MP Janssens, RVF Wadsworth, R AF Clark, RM Fallon, P Gorgen, A Cromaz, M Deleplanque, MA Diamond, RM Lane, GJ Lee, IY Macchiavelli, AO Ramos, RG Stephens, FS Svensson, CE Vetter, K Ward, D Carpenter, MP Janssens, RVF Wadsworth, R TI Very extended shapes in the A similar to 110 region SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIFFERENTIAL LIFETIME MEASUREMENTS; SUPERDEFORMED BANDS; NUCLEI; CD-108; DY-152 AB High-angular-momentum states in Cd-108 were populated via the Ni-64 (Ca-48,4n) reaction at a beam energy of 207 MeV. Gamma rays were detected using the Gammasphere array. A rotational band has been observed with a dynamic moment of inertia and deduced lower Emit of the quadrupole moment suggesting a major-to-minor axis ratio larger than 1.8:1, placing it among the most deformed structures identified in any nucleus, to date. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ York, Dept Phys, York YO1 5DD, N Yorkshire, England. RP Clark, RM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Lane, Gregory/A-7570-2011; Carpenter, Michael/E-4287-2015 OI Lane, Gregory/0000-0003-2244-182X; Carpenter, Michael/0000-0002-3237-5734 NR 26 TC 23 Z9 23 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 NOV 12 PY 2001 VL 87 IS 20 AR 202502 DI 10.1103/PhysRevLett.87.202502 PG 4 WC Physics, Multidisciplinary SC Physics GA 492TD UT WOS:000172182900009 PM 11690470 ER PT J AU Gaskell, D Ahmidouch, A Ambrozewicz, P Anklin, H Arrington, J Assamagan, K Avery, S Bailey, K Baker, OK Beedoe, S Beise, B Breuer, H Brown, DS Carlini, R Cha, J Chant, N Cowley, A Danagoulian, S De Schepper, D Dunne, J Dutta, D Ent, R Gan, L Gasparian, A Geesaman, DF Gilman, R Glashausser, C Gueye, P Harvey, M Hashimoto, O Hinton, W Hofman, G Jackson, C Jackson, HE Keppel, C Kinney, E Koltenuk, D Kyle, G Lung, A Mack, D McKee, D Mitchell, J Mkrtchyan, H Mueller, B Niculescu, G Niculescu, I O'Neill, TG Papavassiliou, V Potterveld, D Reinhold, J Roos, P Sawafta, R Segel, R Stepanyan, S Tadevosyan, V Takahashi, T Tang, L Terburg, B Van Westrum, D Volmer, J Welch, TP Wood, S Yuan, L Zeidman, B Zihlmann, B AF Gaskell, D Ahmidouch, A Ambrozewicz, P Anklin, H Arrington, J Assamagan, K Avery, S Bailey, K Baker, OK Beedoe, S Beise, B Breuer, H Brown, DS Carlini, R Cha, J Chant, N Cowley, A Danagoulian, S De Schepper, D Dunne, J Dutta, D Ent, R Gan, L Gasparian, A Geesaman, DF Gilman, R Glashausser, C Gueye, P Harvey, M Hashimoto, O Hinton, W Hofman, G Jackson, C Jackson, HE Keppel, C Kinney, E Koltenuk, D Kyle, G Lung, A Mack, D McKee, D Mitchell, J Mkrtchyan, H Mueller, B Niculescu, G Niculescu, I O'Neill, TG Papavassiliou, V Potterveld, D Reinhold, J Roos, P Sawafta, R Segel, R Stepanyan, S Tadevosyan, V Takahashi, T Tang, L Terburg, B Van Westrum, D Volmer, J Welch, TP Wood, S Yuan, L Zeidman, B Zihlmann, B TI Longitudinal electroproduction of charged pions from H-1, H-2, and He-3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID POLARIZATION-TRANSFER; DEPENDENCE; SCATTERING; DEUTERIUM; PROTON; EXCESS; NUCLEI; RATIO; IRON AB Separated longitudinal and transverse cross sections for charged pion electroproduction from H-1, H-2, and He-3 were measured at Q(2) = 0.4 (GeV/c)(2) for two values of the invariant mass, W = 1.15 GeV and W = 1.60 GeV, in a search for a mass dependence which would signal the effect of nuclear pions. This is the first such study that includes recoil momenta significantly above the Fermi surface. The longitudinal cross section, if dominated by the pion-pole process, should be sensitive to nuclear pion currents. Comparisons of the longitudinal cross section target ratios to a quasifree calculation reveal a significant suppression in He-3 at W = 1.60 GeV. The W = 1.15 GeV results are consistent with simple estimates of the effect of nuclear pion currents, but are also consistent with pure quasifree production. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Colorado, Boulder, CO USA. Florida Int Univ, Miami, FL 33119 USA. Hampton Univ, Hampton, VA 23668 USA. Univ Illinois, Champaign, IL 61801 USA. Univ Maryland, College Pk, MD 20742 USA. New Mexico State Univ, Las Cruces, NM 88003 USA. N Carolina Agr & Tech State Univ, Greensboro, NC 27411 USA. Northwestern Univ, Evanston, IL 60201 USA. Oregon State Univ, Corvallis, OR 97331 USA. Univ Penn, Philadelphia, PA 19104 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Temple Univ, Philadelphia, PA 19122 USA. Thomas Jefferson Natl Accelerator Fac, Newport News, VA 23606 USA. Tohoku Univ, Sendai, Miyagi 982, Japan. Univ Virginia, Charlottesville, VA 22901 USA. Vrije Univ Amsterdam, NL-1081 HV Amsterdam, Netherlands. Yerevan Phys Inst, Yerevan 375036, Armenia. RP Gaskell, D (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Arrington, John/D-1116-2012 OI Arrington, John/0000-0002-0702-1328 NR 23 TC 16 Z9 16 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 NOV 12 PY 2001 VL 87 IS 20 AR 202301 DI 10.1103/PhysRevLett.87.202301 PG 5 WC Physics, Multidisciplinary SC Physics GA 492TD UT WOS:000172182900007 PM 11690468 ER PT J AU Gates, DA Gorelenkov, NN White, RB AF Gates, DA Gorelenkov, NN White, RB TI Ion heating by fast-particle-induced Alfven turbulence SO PHYSICAL REVIEW LETTERS LA English DT Article ID CYCLOTRON EMISSION; WAVES AB A novel mechanism that directly transfers energy from super-Alfvenic energetic ions to thermal ions in high-beta plasmas is described. The mechanism involves the excitation of compressional Alfven eigenmodes in the frequency range with omega less than or similar to omega (ci). The broadband turbulence resulting from the large number of excited modes causes stochastic diffusion in velocity space, which transfers wave energy to thermal ions. This effect may be important on National Spherical Torus Experiment [M. Ono et al., Nucl. Fusion 40, 557 (2000)] and may scale up to reactor scenarios. This has important implications for low-aspect-ratio reactor concepts, since it potentially allows for increased fusion reactivity in such a device. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Gates, DA (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI White, Roscoe/D-1773-2013 OI White, Roscoe/0000-0002-4239-2685 NR 15 TC 45 Z9 46 U1 1 U2 8 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 NOV 12 PY 2001 VL 87 IS 20 AR 205003 DI 10.1103/PhysRevLett.87.205003 PG 4 WC Physics, Multidisciplinary SC Physics GA 492TD UT WOS:000172182900018 PM 11690479 ER PT J AU Haskel, D Srajer, G Lang, JC Pollmann, J Nelson, CS Jiang, JS Bader, SD AF Haskel, D Srajer, G Lang, JC Pollmann, J Nelson, CS Jiang, JS Bader, SD TI Enhanced interfacial magnetic coupling of Gd/Fe multilayers SO PHYSICAL REVIEW LETTERS LA English DT Article ID X-RAY; CIRCULAR-DICHROISM; GIANT MAGNETORESISTANCE; SCATTERING; SUPERLATTICES; ROUGHNESS; SURFACES; GD AB The spatial extent zeta (AFM) and strength J(AFM) of the antiferromagnetic (AFM) exchange coupling at buried Gd/Fe interfaces in ferrimagnetic [Gd(50 Angstrom )Fe(15, 35 Angstrom)](15) sputtered multilayers is obtained from combined x-ray resonance magnetic reflectivity and magnetic circular dichroism measurements. zeta (AFM), is 4.1(7) Angstrom or similar to1-2 interatomic distances in bulk Gd and Fe; J(AFM) is 1050(90) K, comparable to the ferromagnetic exchange in bulk Fe. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Haskel, D (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RI Bader, Samuel/A-2995-2013 NR 32 TC 72 Z9 72 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 NOV 12 PY 2001 VL 87 IS 20 AR 207201 DI 10.1103/PhysRevLett.87.207201 PG 4 WC Physics, Multidisciplinary SC Physics GA 492TD UT WOS:000172182900045 PM 11690506 ER PT J AU Larese, JZ Marero, DMY Sivia, DS Carlile, CJ AF Larese, JZ Marero, DMY Sivia, DS Carlile, CJ TI Tracking the evolution of interatomic potentials with high resolution inelastic neutron spectroscopy SO PHYSICAL REVIEW LETTERS LA English DT Article ID METHANE; CH4; MOLECULES; MGO(100); SCATTERING; ADSORPTION; MIXTURES; SURFACE; STATE; MGO AB High resolution inelastic neutron scattering has been used to characterize the low temperature rotational dynamics of methane (CH4) films on MgO(100) surfaces as a function of layer thickness. At low temperatures the films grow layer-by-layer similar to the (100) planes of bulk solid CH4. We observe a crossover in the CH4 tunneling spectrum from one characteristic of the 2D solid at monolayer coverages into one that is bulklike (i.e., 3D) when the film is six layers thick. These findings place significant constraints on the microscopic models used to describe CH4-CH4 and CH4-MgO interactions. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Rutherford Appleton Lab, ISIS, Didcot, Oxon, England. Inst Max Von Laue Paul Langevin, Grenoble, France. RP Larese, JZ (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Martin y Marero, David/B-3094-2008 OI Martin y Marero, David/0000-0002-8969-0735 NR 25 TC 15 Z9 15 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 NOV 12 PY 2001 VL 87 IS 20 AR 206102 DI 10.1103/PhysRevLett.87.206102 PG 4 WC Physics, Multidisciplinary SC Physics GA 492TD UT WOS:000172182900028 PM 11690489 ER PT J AU Rehn, LE Birtcher, RC Donnelly, SE Baldo, PM Funk, L AF Rehn, LE Birtcher, RC Donnelly, SE Baldo, PM Funk, L TI Origin of atomic clusters during ion sputtering SO PHYSICAL REVIEW LETTERS LA English DT Article ID DISTRIBUTIONS; IRRADIATION; BOMBARDMENT; METALS; SILVER AB Previous studies have shown that the size distributions of small clusters (n less than or equal to 40; n = number of atoms/cluster) generated by sputtering obey an inverse power law with an exponent between -8 and -4. Here we report electron microscopy studies of the size distributions of larger clusters (n greater than or equal to 500) sputtered by high-energy ion impacts. These new measurements also yield an inverse power law, but one with an exponent of -2 and one independent of sputtering yield, indicating that the large clusters are produced when shock waves, generated by subsurface displacement cascades, ablate the surface. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Rehn, LE (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 14 TC 38 Z9 38 U1 1 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 12 PY 2001 VL 87 IS 20 AR 207601 DI 10.1103/PhysRevLett.87.207601 PG 4 WC Physics, Multidisciplinary SC Physics GA 492TD UT WOS:000172182900051 PM 11690512 ER PT J AU Reina, L Dawson, S AF Reina, L Dawson, S TI Next-to-leading order results for t(t)over-bar-h production at the Tevatron SO PHYSICAL REVIEW LETTERS LA English DT Article ID ONE-LOOP INTEGRALS; BOSON PRODUCTION; COLLISIONS AB We compute the O(alpha (3)(s)) inclusive total cross section for the process p (p) over bar --> t (t) over barh in the standard model, at root sH = 2 TeV. The next-to-leading order corrections drastically reduce the renormalization and factorization scale dependence of the Born cross section and slightly decrease the total cross section for renormalization and factorization scales between m(t) and 2m(t). C1 Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Reina, L (reprint author), Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. NR 25 TC 108 Z9 108 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 NOV 12 PY 2001 VL 87 IS 20 AR 201804 DI 10.1103/PhysRevLett.87.201804 PG 4 WC Physics, Multidisciplinary SC Physics GA 492TD UT WOS:000172182900004 PM 11690465 ER PT J AU Zhu, SL Maekawa, CM Holstein, BR Ramsey-Musolf, MJ AF Zhu, SL Maekawa, CM Holstein, BR Ramsey-Musolf, MJ TI Parity-violating photoproduction of pi(+/-) on the Delta resonance SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUARK-MODEL; NEUTRAL-CURRENT; HYPERON DECAYS; ANAPOLE MOMENT; NUCLEON; BARYONS AB We analyze the real-photon asymmetry A(gamma)(+/-) for the parity-violating (PV) pi (+/-) production on the Delta resonance via the reactions <()over right arrow> + p --> Delta (+) --> pi (+) + n and <()over right arrow> + d --> Delta (0) + p --> pi (-) + p + p. This asymmetry is nonvanishing due to a PV gammaN Delta coupling constant, d(Delta)(+/-). We argue that an experimental determination of this coupling would be of interest for hadron dynamics, possibly shedding light on the S-wave/P-wave puzzle in the hyperon nonleptonic decays and the violation of Hara's theorem in weak radiative hyperon decays. C1 CALTECH, Kellogg Radiat Lab 10638, Pasadena, CA 91125 USA. Univ Connecticut, Dept Phys, Storrs, CT 06269 USA. Univ Massachusetts, Dept Phys, Amherst, MA 01003 USA. Thomas Jefferson Natl Accelerator Facil, Theory Grp, Newport News, VA 23606 USA. RP Zhu, SL (reprint author), CALTECH, Kellogg Radiat Lab 10638, Pasadena, CA 91125 USA. NR 34 TC 19 Z9 19 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 12 PY 2001 VL 87 IS 20 AR 201802 DI 10.1103/PhysRevLett.87.201802 PG 4 WC Physics, Multidisciplinary SC Physics GA 492TD UT WOS:000172182900002 PM 11690463 ER PT J AU Balona, LA Aerts, C Bozic, H Guinan, EF Handler, G James, DJ Kaye, AB Shobbrook, RR AF Balona, LA Aerts, C Bozic, H Guinan, EF Handler, G James, DJ Kaye, AB Shobbrook, RR TI Short period line profile and light variations in the Be star omega Orionis SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE line : profiles; stars : early-type; stars : emission-line, Be; stars : individual : omega Ori ID ROTATIONAL VELOCITIES; SHELL STARS; VARIABILITY; SOUTHERN; CLOUDS AB We present the results of a multisite spectroscopic and photometric campaign on the Be star omega Orionis. From the photometry and radial velocity variation of several spectral lines, we confirm that the star is a variable with period P = 0.97 d. Only one period can be extracted from both the photometric and radial velocity observations. We find that the projected rotational velocity from the helium lines (v sin i = 173 km s(-1)) is considerably smaller than from the metal lines (v sin i = 226 km s(-1)). The line profiles show an excess absorption feature moving from blue to red for half the period and from red to blue for the other half of the period. Another excess absorption feature moves exactly out of phase. The excess absorption features are present in photospheric lines as well as in lines which are significantly affected by circumstellar material, such as H beta. From this we conclude that the periodic variations are most probably associated with corotating circumstellar material. C1 S African Astron Observ, ZA-7935 Cape Town, South Africa. Katholieke Univ Leuven, Inst Sterrenkunde, Louvain, Belgium. Univ Zagreb, Fac Geodesy, Hvar Observ, Zagreb 10000, Croatia. Villanova Univ, Dept Astron & Astrophys, Villanova, PA 19085 USA. Univ St Andrews, Sch Phys & Astron, St Andrews KY16 9SS, Fife, Scotland. Observ Geneva, CH-1290 Sauverny, Switzerland. Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. Australian Natl Univ, Res Sch Astron & Astrophys, Canberra, ACT, Australia. RP Balona, LA (reprint author), S African Astron Observ, POB 9, ZA-7935 Cape Town, South Africa. NR 17 TC 8 Z9 8 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD NOV 11 PY 2001 VL 327 IS 4 BP 1288 EP 1296 DI 10.1046/j.1365-8711.2001.04831.x PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 495MA UT WOS:000172343900031 ER PT J AU Redin, SI Ryskulov, NM Fedotovich, GV Khazin, BI Bunce, GM Danby, GT Jackson, JW Morse, WM Prigl, R Semertzidis, YK Efstathiadis, E Roberts, BL Grossmann, A Jungmann, K Putlitz, GZ von Walter, P Dhawan, SK Farley, FJM Grosse-Perdekamp, M Hughes, VW Kawall, D AF Redin, SI Ryskulov, NM Fedotovich, GV Khazin, BI Bunce, GM Danby, GT Jackson, JW Morse, WM Prigl, R Semertzidis, YK Efstathiadis, E Roberts, BL Grossmann, A Jungmann, K Putlitz, GZ von Walter, P Dhawan, SK Farley, FJM Grosse-Perdekamp, M Hughes, VW Kawall, D TI Radial magnetic field measurements with a Hall probe device in the muon (g-2) storage ring magnet at BNL SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE Hall probe; magnetic field measurement; ultraprecise superferric magnet AB A Hall probe device has been built to measure the radial component of the magnetic field in the muon (g-2) storage ring at Brookhaven National Laboratory. The ultraprecise (g-2) magnet provides a dominantly vertical magnetic field of about 1.45 T. In order to limit the vertical shift of the muon orbit, the average radial field component should be no more than 5 x 10(-5) of, the vertical field. Our measurements with the Hall probe device achieved an accuracy of 1 x 10(-5). which is one of the most precise measurements with Hall probes. This provides adequate accuracy for shimming and control of the radial field. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Yale Univ, Dept Phys, New Haven, CT 06511 USA. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Brookhaven Natl Lab, Upton, NY 11973 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. Univ Heidelberg, Inst Phys, D-69120 Heidelberg, Germany. RP Redin, SI (reprint author), Yale Univ, Dept Phys, New Haven, CT 06511 USA. RI Jungmann, Klaus/A-7142-2010; jungmann, klaus/H-1581-2013; Semertzidis, Yannis K./N-1002-2013 OI jungmann, klaus/0000-0003-0571-4072; NR 10 TC 8 Z9 8 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 NOV 11 PY 2001 VL 473 IS 3 BP 260 EP 268 DI 10.1016/S0168-9002(01)00859-2 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 492PE UT WOS:000172176100003 ER PT J AU Menou, K Vanden Berg, DE Kim, RSJ Knapp, GR Richards, GT Strateva, I Fan, XH Gunn, JE Hall, PB Heckman, T Krolik, J Lupton, RH Schneider, DP York, DG Anderson, SF Bahcall, NA Brinkmann, J Brunner, R Csabai, I Fukugita, M Hennessy, GS Kunszt, PZ Lamb, DQ Munn, JA Nichol, RC Szokoly, GP AF Menou, K Vanden Berg, DE Kim, RSJ Knapp, GR Richards, GT Strateva, I Fan, XH Gunn, JE Hall, PB Heckman, T Krolik, J Lupton, RH Schneider, DP York, DG Anderson, SF Bahcall, NA Brinkmann, J Brunner, R Csabai, I Fukugita, M Hennessy, GS Kunszt, PZ Lamb, DQ Munn, JA Nichol, RC Szokoly, GP TI Broad absorption line quasars in the Sloan Digital Sky Survey with VLA first radio detections SO ASTROPHYSICAL JOURNAL LA English DT Article DE catalogs; galaxies : active; quasars : absorption lines; quasars : general; radio continuum : general; surveys ID STELLAR OBJECTS; QSO; REDSHIFT; EMISSION AB We present 13 broad absorption line (BAL) quasars, including 12 new objects, identified in the Sloan Digital Sky Survey (SDSS) and matched within 2 " to sources in the FIRST radio survey catalog. The surface density of this sample of radio-detected BAL quasars is 4.5 +/- 1.2 per 100 deg(2), i.e., approximately 4 times as high as previously found by the shallower FIRST Bright Quasar Survey (FBQS). A majority of these radio-detected BAL quasars are moderately radio-loud objects. The fraction of BAL quasars in the entire radio quasar sample, 4.8% +/- 1.3%, is comparable to the fraction of BAL quasars among the SDSS optical quasar sample (ignoring selection effects). We estimate that the true fraction of BAL quasars (mostly "HiBALs") in the radio sample is 9.2% +/- 2.6%, once selection effects are accounted for. We caution that the absorption troughs of four of the 13 radio-detected quasars considered do not strictly satisfy the standard BALnicity criteria. One or possibly two of the new radio-detected BAL quasars are of the rare "FeLoBAL" type. BAL quasars are generally redder than the median SDSS quasar at the same redshift. C1 Princeton Univ Observ, Princeton, NJ 08544 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Inst Adv Study, Princeton, NJ 08540 USA. Pontificia Univ Catolica Chile, Fac Fis, Dept Astron & Astrofis, Santiago 22, Chile. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Apache Point Observ, Sunspot, NM 88349 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Univ Tokyo, Inst Cosm Ray Res, Midori Ku, Tokyo 1888502, Japan. USN Observ, Washington, DC 20392 USA. USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15232 USA. Astrophys Inst Potsdam, D-14482 Potsdam, Germany. RP Menou, K (reprint author), Princeton Univ Observ, Peyton Hall, Princeton, NJ 08544 USA. RI Csabai, Istvan/F-2455-2012; OI Kunszt, Peter/0000-0003-0933-4763; Csabai, Istvan/0000-0001-9232-9898 NR 32 TC 49 Z9 49 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 2001 VL 561 IS 2 BP 645 EP 652 DI 10.1086/323218 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492VT UT WOS:000172188800011 ER PT J AU Najita, J Bergin, EA Ullom, JN AF Najita, J Bergin, EA Ullom, JN TI X-ray desorption of molecules from grains in protoplanetary disks SO ASTROPHYSICAL JOURNAL LA English DT Article DE circumstellar matter; dust, extinction; X-rays : ISM; X-rays : stars ID SPECTRAL ENERGY-DISTRIBUTIONS; INTERSTELLAR DUST PARTICLES; YOUNG STELLAR OBJECTS; T-TAURI STARS; SIZE DISTRIBUTION; THERMAL-CONDUCTIVITY; CIRCUMSTELLAR DISKS; ACCRETION DISKS; EMISSION; EXTINCTION AB We examine the ability of stellar X-rays to desorb molecules from grains in outer protoplanetary disks. In particular, we consider the possibility of spot heating by X-rays and examine its effectiveness, compared to whole grain heating by X-rays, in sustaining a gas-phase abundance of CO. As found in previous studies, whole grain heating is effective only for small grains (<500 ). As a result, large grains are a permanent sink of CO, and whole grain heating cannot sustain an equilibrium gas-phase abundance of CO. Spot heating, in which the incident X-ray deposits energy in only a restricted region of the grain volume and which may occur as a consequence of the aggregate nature of grains, proves to be more promising. Assuming that grains are comprised of many thermal subunits that are poorly connected thermally, we find that spot heating is efficient at all grain sizes if large grains are effectively "coated" with small grains less than or similar to 100 Angstrom in size. We discuss the implications of X-ray spot heating for the interpretation of millimeter emission-line studies of outer protoplanetary disks. C1 Natl Opt Astron Observ, Tucson, AZ 85719 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Najita, J (reprint author), Natl Opt Astron Observ, 950 N Cherry Ave, Tucson, AZ 85719 USA. NR 54 TC 26 Z9 26 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 2001 VL 561 IS 2 BP 880 EP 889 DI 10.1086/323320 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492VT UT WOS:000172188800031 ER PT J AU Li, H Lovelace, RVE Finn, JM Colgate, SA AF Li, H Lovelace, RVE Finn, JM Colgate, SA TI Magnetic helix formation driven by Keplerian disk rotation in an external plasma pressure: The initial expansion stage SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; magnetic fields; MHD; plasmas ID DOUBLE RADIO-SOURCES; ACCRETION DISKS; MAGNETOHYDRODYNAMIC SIMULATIONS; ASTROPHYSICAL JETS; CORONAL ARCADES; FIELD; EVOLUTION; EQUILIBRIUM; OUTFLOWS; MODEL AB We study the evolution of a magnetic arcade that is anchored to an accretion disk and is sheared by the differential rotation of a Keplerian disk. By including an extremely low external plasma pressure at large distances, we obtain a sequence of axisymmetric magnetostatic equilibria and show that there is a fundamental difference between field lines that are affected by the plasma pressure and those that are not (i.e., force free). Force-free fields, while being twisted by the differential rotation of the disk, expand outward at an angle of similar to 60 degrees away from the rotation axis, consistent with the previous studies. These force-free field lines, however, are enclosed by the outer field lines, which originate from small disk radii and come back to the disk at large radii. These outer fields experience most of the twist, and they are also affected most by the external plasma pressure. At large cylindrical radial distances, magnetic pressure and plasma pressure are comparable so that any further radial expansion of magnetic fields is prevented or slowed down greatly by this pressure. This hindrance to cylindrical radial expansion causes most of the added twist to be distributed on the ascending portion of the field lines, close to the rotation axis. Since these field lines are twisted most, the increasing ratio of the toroidal B-phi component to the poloidal component B-R,B-z eventually results in the collimation of magnetic energy and flux around the rotation axis. We discuss the difficulty with adding a large number of twists within the limitations of the magnetostatic approximation. C1 Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Li, H (reprint author), Los Alamos Natl Lab, Div Appl Phys, MS B288, Los Alamos, NM 87545 USA. NR 40 TC 41 Z9 41 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 2001 VL 561 IS 2 BP 915 EP 923 DI 10.1086/323631 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492VT UT WOS:000172188800033 ER PT J AU Salmonson, JD Wilson, JR AF Salmonson, JD Wilson, JR TI Neutrino annihilation between binary neutron stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; gamma rays : theory; neutrinos ID ENERGY DEPOSITION; BURSTS; MODEL AB We calculate the neutrino pair annihilation rate into electron pairs between two neutron stars in a binary system. We present a closed formula for the energy deposition rate at any point between the stars, where each neutrino of a pair derives from each star, and compare this result with that in which all neutrinos derive from a single neutron star. An approximate generalization of this formula is given to include the relativistic effects of gravity. We find that this interstar neutrino annihilation is a significant contributor to the energy deposition between heated neutron star binaries. In particular, for two neutron stars near their last stable orbit, interstar neutrino annihilation energy deposition is almost equal to that of single-star energy deposition. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Salmonson, JD (reprint author), Lawrence Livermore Natl Lab, POB 808,L-095, Livermore, CA 94551 USA. NR 12 TC 12 Z9 12 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 2001 VL 561 IS 2 BP 950 EP 956 DI 10.1086/323319 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492VT UT WOS:000172188800038 ER PT J AU Pruet, J Fuller, GM Cardall, CY AF Pruet, J Fuller, GM Cardall, CY TI On steady state neutrino-heated ultrarelativistic winds from compact objects SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; neutrinos; relativity; stars : neutron ID R-PROCESS NUCLEOSYNTHESIS; RAY BURST FIREBALLS; DRIVEN WINDS; STARS; YOUNG AB We study steady state winds from compact objects in the regime where the wind velocity at infinity is ultrarelativistic. This may have relevance to some models of gamma-ray bursts (GRBs). Particular attention is paid to the case in which neutrinos provide the heating. Unless the neutrino luminosity is very large, L > 10(54) ergs s(-1), the only allowed steady state solutions are those where energy deposition is dominated by neutrino-antineutrino annihilation at the sonic point. In this case, the matter temperature near the neutron star surface is low, less than 1 MeV for typical neutrino luminosities. This is in contrast to the case for subrelativistic winds discussed in the context of supernovae, where the matter temperature near the neutron star approximates the temperature characterizing the neutrinos. We also investigate the setting of the neutron-to-proton ratio (N/P) in these winds and find that only for large (>10 MeV) electron-neutrino or electron-antineutrino temperatures is N/P entirely determined by neutrino capture. Otherwise, N/P retains an imprint of conditions in the neutron star. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. RP Pruet, J (reprint author), Univ Calif San Diego, Dept Phys, Code 0354,9500 Gilman Dr, La Jolla, CA 92093 USA. NR 18 TC 10 Z9 10 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 2001 VL 561 IS 2 BP 957 EP 963 DI 10.1086/322498 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492VT UT WOS:000172188800039 ER PT J AU Fournier, KB May, MJ Liedahl, DA Pacella, D Finkenthal, M Leigheb, M Mattioli, M Goldstein, WH AF Fournier, KB May, MJ Liedahl, DA Pacella, D Finkenthal, M Leigheb, M Mattioli, M Goldstein, WH TI Electron-density-dependent extreme-ultraviolet intensity ratios from L-shell iron ions in the Frascati Tokamak Upgrade SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic data; methods : laboratory; novae, cataclysmic variables; stars : coronae; X-rays : stars ID EXCITATION COLLISION STRENGTHS; HIGHLY IONIZED IRON; FLUORINE-LIKE IONS; X-RAY-SPECTRUM; ATOMIC DATA; IMPACT EXCITATION; FE-XXIV; LABORATORY MEASUREMENTS; CORONAL STRUCTURE; RATE COEFFICIENTS AB We present measurements of density-sensitive extreme-ultraviolet line ratios from highly charged L-shell iron ions in the Frascati Tokamak Upgrade plasma at densities more than a factor of 2 higher than previously observed. These observations are directly applicable to recent measurements of emission from high-density regions of the atmospheres of W Ursae Majoris binary stars and DQ Herculis type cataclysmic variables. We compare our observations to collisional-radiative models with large atomic structure data sets computed with the HULLAC suite of codes. We find good agreement for nearly all cases where spectral blending does not compromise our data. We also compare the predictions of our HULLAC models with ratios given by the Brickhouse, Raymond, & Smith code; we find agreement to better than 20% between the two calculations independent of the size of the atomic model. Our results confirm observations of very high electron densities (>10(14) cm(-3)) in the coronae of 44i Boo and EX Hya. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Fournier, KB (reprint author), Lawrence Livermore Natl Lab, POB 808,L-41, Livermore, CA 94551 USA. EM fournier2@llnl.gov NR 67 TC 8 Z9 8 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 2001 VL 561 IS 2 BP 1144 EP 1153 DI 10.1086/323371 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492VT UT WOS:000172188800052 ER PT J AU Reilly, KT Bloom, ED Focke, W Giebels, B Godfrey, G Parkinson, PMS Shabad, G Ray, PS Bandyopadhyay, RM Wood, KS Wolff, MT Fritz, GG Hertz, P Kowalski, MP Lovellette, MN Yentis, DJ Scargle, JD AF Reilly, KT Bloom, ED Focke, W Giebels, B Godfrey, G Parkinson, PMS Shabad, G Ray, PS Bandyopadhyay, RM Wood, KS Wolff, MT Fritz, GG Hertz, P Kowalski, MP Lovellette, MN Yentis, DJ Scargle, JD TI USA experiment observation of spectral and timing evolution during the 2000 outburst of XTE J1550-564 SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; binaries : general; stars : individual (XTE J1550-564); X-rays : stars ID ACCRETION; DISKS AB We report on timing and spectral observations of the 2000 outburst of XTE J1550-64 made by the Unconventional Stellar Aspect (USA) experiment on board the Advanced Research and Global Observation Satellite (ARGOS). We observe a low-frequency quasi-periodic oscillation with a centroid frequency that tends to increase with increasing flux and a fractional rms amplitude that is correlated with the hardness ratio. Several high-frequency quasi-periodic oscillations were detected by Rossi X-Ray Timing Explorer during periods where the low-frequency quasi-periodic oscillation was seen to be weakening or not detectable at all. The evolution of the hardness ratio (4-16 keV/1-4 keV) with time and source flux is examined. The hardness-intensity diagram shows a cyclical movement in the counterclockwise direction and possibly indicates the presence of two independent accretion flows: a thin-disk flow and a hot sub-Keplerian flow. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. USN, Res Lab, EO Hulburt Ctr Space Res, Washington, DC 20375 USA. NASA, Ames Res Ctr, Div Space Sci, Moffett Field, CA 94305 USA. RP Reilly, KT (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. OI Ray, Paul/0000-0002-5297-5278 NR 22 TC 8 Z9 8 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 10 PY 2001 VL 561 IS 2 BP L183 EP L186 DI 10.1086/324756 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492VU UT WOS:000172188900010 ER PT J AU Melnikov, K AF Melnikov, K TI On the theoretical uncertainties in the muon anomalous magnetic moment SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article ID HADRONIC CONTRIBUTIONS; ELECTROWEAK CORRECTIONS; G-2; ANNIHILATION; VALUES; DECAY AB I present a fairly detailed discussion of various contributions to the anomalous magnetic moment of the muon ap. I try to give an unbiased evaluation of the validity of the SM prediction for this quantity and to point out some delicate issues involved in its calculation. I conclude that the theory uncertainties in the SM prediction for the muon anomalous magnetic moment axe underestimated and a great deal of work will be required to reduce these uncertainties to the level required by experiment. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Melnikov, K (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM melnikov@slac.stanjord.edu NR 42 TC 71 Z9 71 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X EI 1793-656X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD NOV 10 PY 2001 VL 16 IS 28 BP 4591 EP 4612 DI 10.1142/S0217751X01005602 PG 22 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 496JT UT WOS:000172393000006 ER PT J AU Suzuki, M AF Suzuki, M TI Extrapolation of K -> pi pi decay amplitude SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article ID ELECTROMAGNETIC CORRECTIONS; LEADING LOGARITHMS; EPSILON'/EPSILON; K->PI-PI AB We examine the uncertainties involved in the off-mass-shell extrapolation of the K --> pi pi decay amplitude with emphasis on those aspects that have so far been overlooked or ignored. Among them are initial-state interactions, choice of the extrapolated kaon field, and the relation between the asymptotic behavior and the zeros of the decay amplitude. In the inelastic region the phase of the decay amplitude cannot be determined by strong interaction alone and even its asymptotic value cannot be deduced from experiment. More a fundamental issue is intrinsic nonuniqueness of off-shell values of hadronic matrix elements in general. Though we are hampered with the complexity of intermediate-energy meson interactions, we attempt to obtain a quantitative idea of the uncertainties due to the inelastic region and find that they can be much larger than more optimistic views portray. If large uncertainties exist, they have unfortunate implications in the numerical accuracy of the computation of the direct CP violation parameter epsilon'. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Suzuki, M (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 47 TC 2 Z9 2 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD NOV 10 PY 2001 VL 16 IS 28 BP 4637 EP 4658 DI 10.1142/S0217751X01005638 PG 22 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 496JT UT WOS:000172393000008 ER PT J AU Wu, Z Ehrlich, SN Matthies, B Herwig, KW Dai, PC Volkmann, UG Hansen, FY Taub, H AF Wu, Z Ehrlich, SN Matthies, B Herwig, KW Dai, PC Volkmann, UG Hansen, FY Taub, H TI Growth of n-alkane films on a single-crystal substrate SO CHEMICAL PHYSICS LETTERS LA English DT Article ID X-RAY-DIFFRACTION; SURFACE; MONOLAYERS; INTERFACES; GRAPHITE; BUTANE AB The structure and growth mode of alkane films (n-CnH2n+2; n = 4, 6, 7) adsorbed on a Ag(111) surface have been investigated by synchrotron X-ray scattering. New models are proposed for the butane (n = 4) and hexane (n = 6) monolayer and butane bilayer structures. Specular reflectivity scans reveal that growth of all films is preempted between two and three layers by nucleation of bulk particles oriented with a single bulk crystal plane parallel to the film. In the case of butane, the bulk particles also have a fixed azimuthal relationship with the film resulting in complete epitaxy. (C) 2001 Published by Elsevier Science B.V. C1 Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. Univ Missouri, Res Reactor, Columbia, MO 65211 USA. Frederick Seitz Mat Res Lab, Urbana, IL 61801 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Goodyear Tire & Rubber Co, Corp Res Div, Akron, OH 44305 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Catholic Univ Chile, Fac Fis, Santiago 22, Chile. Tech Univ Denmark, Dept Chem, DK-2800 Lyngby, Denmark. RP Taub, H (reprint author), Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA. RI Herwig, Kenneth/F-4787-2011; Dai, Pengcheng /C-9171-2012; Volkmann, Ulrich/H-1802-2014 OI Dai, Pengcheng /0000-0002-6088-3170; NR 15 TC 28 Z9 28 U1 0 U2 7 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 NOV 9 PY 2001 VL 348 IS 3-4 BP 168 EP 174 DI 10.1016/S0009-2614(01)01147-2 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 491CF UT WOS:000172089900002 ER PT J AU Burma, S Chen, BP Murphy, M Kurimasa, A Chen, DJ AF Burma, S Chen, BP Murphy, M Kurimasa, A Chen, DJ TI ATM phosphorylates histone H2AX in response to DNA double-strand breaks SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID DEPENDENT PROTEIN-KINASE; EXPRESSION; LYMPHOMA; DAMAGE; REPAIR; CELLS AB A very early step in the response of mammalian cells to DNA double-strand breaks is the phosphorylation of histone H2AX at serine 139 at the sites of DNA damage. Although the phosphatidylinositol 3-kinases, DNA-PK (DNA-dependent protein kinase), ATM (ataxia telangiectasia mutated), and ATR (ATM and Rad3-related), have all been implicated in H2AX phosphorylation, the specific kinase involved has not yet been identified. To definitively identify the specific kinase(s) that phosphorylates H2AX in vivo, we have utilized DNA-PKcs -/- and Atm-/- cell lines and mouse embryonic fibroblasts. We find that H2AX phosphorylation and nuclear focus formation are normal in DNA-PKes-/- cells and severely compromised in Atm-/- cells. We also find that ATM can phosphorylate H2AX in vitro and that ectopic expression of ATM in Atm-/- fibroblasts restores H2AX phosphorylation in vivo. The minimal H2AX phosphorylation in Atm-/- fibroblasts can be abolished by low concentrations of wortmannin suggesting that DNA-PK, rather than ATR, is responsible for low levels of H2AX phosphorylation in the absence of ATM. Our results clearly establish ATM as the major kinase involved in the phosphorylation of H2AX and suggest that ATM is one of the earliest kinases to be activated in the cellular response to double-strand breaks. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Chen, DJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NCI NIH HHS [CA50519] NR 28 TC 937 Z9 971 U1 5 U2 40 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 NOV 9 PY 2001 VL 276 IS 45 BP 42462 EP 42467 DI 10.1074/jbc.C100466200 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 497HY UT WOS:000172450400118 PM 11571274 ER PT J AU Nittis, T George, GN Winge, DR AF Nittis, T George, GN Winge, DR TI Yeast Sco1, a protein essential for cytochrome c oxidase function is a Cu(I)-binding protein SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID SACCHAROMYCES-CEREVISIAE; SUBUNIT-II; MUTATIONAL ANALYSIS; COPPER-METABOLISM; GENE; DEFICIENCY; PURIFICATION; EXPRESSION; IDENTIFICATION; LOCALIZATION AB Sco1 is a conserved essential protein, which has been implicated in the delivery of copper to cytochrome c oxidase, the last enzyme of the electron transport chain. In this study, we show for the first time that the purified C-terminal domain of yeast Sco1 binds one Cu(I)/monomer. X-ray absorption spectroscopy suggests that the Cu(I) is ligated via three ligands, and we show that two cysteines, present in a conserved motif CXXXC, and a conserved histidine are involved in Cu(I) ligation. The mutation of any one of the conserved residues in Sco1 expressed in yeast abrogates the function of Sco1 resulting in a non-functional cytochrome c oxidase complex. Thus, the function of Sco1 correlates with Cu(I) binding. Data obtained from size-exclusion chromatography experiments with mitochondrial lysates suggest that full-length Sco1 may be oligomeric in vivo. C1 Univ Utah, Hlth Sci Ctr, Dept Med, Salt Lake City, UT 84132 USA. Univ Utah, Hlth Sci Ctr, Dept Biochem, Salt Lake City, UT 84132 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. RP Winge, DR (reprint author), Univ Utah, Hlth Sci Ctr, Dept Med, Salt Lake City, UT 84132 USA. RI Winge, Dennis/G-3611-2010; George, Graham/E-3290-2013 FU NIEHS NIH HHS [ES 03817] NR 45 TC 128 Z9 130 U1 0 U2 5 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD NOV 9 PY 2001 VL 276 IS 45 BP 42520 EP 42526 DI 10.1074/jbc.M107077200 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 497HY UT WOS:000172450400126 PM 11546815 ER PT J AU Davis, DP Gallo, G Vogen, SM Dul, JL Sciarretta, KL Kumar, A Raffen, R Stevens, FJ Argon, Y AF Davis, DP Gallo, G Vogen, SM Dul, JL Sciarretta, KL Kumar, A Raffen, R Stevens, FJ Argon, Y TI Both the environment and somatic mutations govern the aggregation pathway of pathogenic immunoglobulin light chain SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE protein aggregation diseases; copper; light chain amyloidosis; light chain deposition disease ID DEPOSITION DISEASE; ENDOPLASMIC-RETICULUM; PROTEIN CONFORMATION; VARIABLE DOMAIN; COPPER; AMYLOIDOSIS; MEMBRANE; MENKES; CONSEQUENCES; FIBROBLASTS AB lDeposition of monoclonal immunoglobulin light chain (LC) aggregates in tissues is the hallmark of a class of fatal diseases with no effective treatment. In the most prevalent diseases two different types of LC aggregates are observed: fibrillar deposits in LC amyloidosis (AL) and granular aggregates in LC deposition disease (LCDD). The mechanisms by which a given LC forms either type of aggregate are not understood. Although some LCs are more aggregation-prone than others, this does not appear to be due to specific sequence determinants, but more likely from global properties that can be introduced by multiple somatic mutations. Moreover, a single LC isotype can sometimes form both fibrillar and granular aggregates within the same patient. To better understand how the different aggregation pathways arise, we developed a series of in vitro assays to analyze the formation of distinct aggregate types. The recombinant kappa IV LC (SMA) assembles into fibrils when agitated. We now show that SMA can also form granular aggregates upon exposure to copper, and that this aggregation can occur not only in vitro, but also in cells. A constellation of somatic mutations, consisting of His89/His94/Gln96, is sufficient to confer sensitivity to copper on wild-type kappa IV proteins. The formation of both types of aggregates is inhibited by synthetic peptides derived from the LC variable domain. However, the peptide that inhibits fibrillar aggregation is different from the peptide that inhibits copper-induced aggregation. Thus, distinct molecular surfaces of the LC underly each type of aggregate. We conclude that both the intrinsic properties of the sequence and extrinsic conditions govern the aggregation pathway of a LC. (C) 2001 Academic Press. C1 Univ Chicago, Dept Pathol, Chicago, IL 60637 USA. Univ Chicago, Comm Immunol, Chicago, IL 60637 USA. Univ Chicago, Dept Mol Genet & Cell Biol, Chicago, IL 60637 USA. NYU, Med Ctr, Dept Pathol, New York, NY 10016 USA. Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. RP Argon, Y (reprint author), Univ Chicago, Dept Pathol, 5841 S Maryland Ave, Chicago, IL 60637 USA. FU NIA NIH HHS [AG-18001]; NIAID NIH HHS [AI-30178]; NIDDK NIH HHS [DK43757, DK07074] NR 52 TC 38 Z9 40 U1 0 U2 4 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD NOV 9 PY 2001 VL 313 IS 5 BP 1021 EP 1034 DI 10.1006/jmbi.2001.5092 PG 14 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 492YN UT WOS:000172195300009 PM 11700059 ER PT J AU Lowe, J Li, H Downing, KH Nogales, E AF Lowe, J Li, H Downing, KH Nogales, E TI Refined structure of alpha beta-tubulin at 3.5 A resolution SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE tubulin; taxol; zinc-sheets; electron crystallography; crystallographic refinement ID GUANINE-NUCLEOTIDE-BINDING; ELECTRON CRYSTALLOGRAPHY; GTP HYDROLYSIS; DENSITY MAPS; MICROTUBULE; MODEL; BACTERIORHODOPSIN; DIMER; CRYSTALS; DYNAMICS AB We present a refined model of the ap-tubulin dimer to 3.5 Angstrom resolution. An improved experimental density for the zinc-induced tubulin sheets was obtained by adding 114 electron diffraction patterns at 40-60 degrees tilt and increasing the completeness of structure factor amplitudes to 84.7%. The refined structure was obtained using maximum-likelihood including phase information from experimental images, and simulated annealing Cartesian refinement to an R-factor of 23.2 and free R-factor of 29.7. The current model includes residues alpha :2-34, alpha :61-439, beta :2-437, one molecule of GTP, one of GDP, and one of taxol, as well as one magnesium ion at the non-exchangeable nucleotide site, and one putative zinc ion near the M-loop in the alpha -tubulin subunit. The acidic C-terminal tails could not be traced accurately, neither could the N-terminal loop including residues 35-60 in the alpha -subunit. There are no major changes in the overall fold of tubulin with respect to the previous structure, testifying to the quality of the initial experimental phases. The overall geometry of the model is, however, greatly improved, and the position of side-chains, especially those of exposed polar/charged groups, is much better defined. Three short protein sequence frame shifts were detected with respect to the non-refined structure. In light of the new model we discuss details of the tubulin structure such as nucleotide and taxol binding sites, lateral contacts in zinc-sheets, and the significance of the location of highly conserved residues. (C) 2001 Academic Press. C1 Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. MRC, Mol Biol Lab, Cambridge CB2 2QH, England. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. RP Nogales, E (reprint author), Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RI Lowe, Jan/B-3882-2011; OI Lowe, Jan/0000-0002-5218-6615 FU NIGMS NIH HHS [GM46033] NR 47 TC 682 Z9 700 U1 1 U2 62 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD NOV 9 PY 2001 VL 313 IS 5 BP 1045 EP 1057 DI 10.1006/jmbi.2001.5077 PG 13 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 492YN UT WOS:000172195300011 PM 11700061 ER PT J AU Griffith, SC Sawaya, MR Boutz, DR Thapar, N Katz, JE Clarke, S Yeates, TO AF Griffith, SC Sawaya, MR Boutz, DR Thapar, N Katz, JE Clarke, S Yeates, TO TI Crystal structure of a protein repair methyltransferase from Pyrococcus furiosus with its L-isoaspartyl peptide substrate SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE protein repair; methyltransferase; S-adenosylmethionine; D-amino acids; protein isomerization ID ADENOSYLMETHIONINE-DEPENDENT METHYLTRANSFERASES; D-ASPARTYL RESIDUES; S-ADENOSYLMETHIONINE; CARBOXYL METHYLTRANSFERASE; O-METHYLTRANSFERASE; CATALYTIC DOMAIN; SEQUENCE MOTIFS; IN-VITRO; ERYTHROCYTES; ACCUMULATION AB Protein L-isoaspartyl (D-aspartyl) methyltransferases (EC 2.1.1.77) are found in almost all organisms. These enzymes catalyze the S-adenosylmethionine (AdoMet)-dependent methylation of isomerized and racemized aspartyl residues in age-damaged proteins as part of an essential protein repair process. Here, we report crystal structures of the repair methyltransferase at resolutions up to 1.2 Angstrom from the hyperthermophilic archaeon Pyrococcus furiosus. Refined structures include binary complexes with the active cofactor AdoMet, its reaction product S-adenosylhomocysteine (AdoHcy), and adenosine. The enzyme places the methyl-donating cofactor in a deep, electrostatically negative pocket that is shielded from solvent. Across the multiple crystal structures visualized, the presence or absence of the methyl group on the cofactor correlates with a significant conformational change in the enzyme in a loop bordering the active site, suggesting a role for motion in catalysis or cofactor exchange. We also report the structure of a ternary complex of the enzyme with adenosine and the methyl-accepting polypeptide substrate VYP(L-isoAsp)HA at 2.1 Angstrom. The substrate binds in a narrow active site cleft with three of its residues in an extended conformation, suggesting that damaged proteins may be locally denatured during the repair process in cells. Manual and computer-based docking studies on different isomers help explain how the enzyme uses steric effects to make the critical distinction between normal L-aspartyl and age-damaged L-isoaspartyl and D-aspartyl residues. (C) 2001 Academic Press. C1 Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Inst Mol Biol, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, DOE Lab Struct Biol & Mol Med, Los Angeles, CA 90095 USA. RP Yeates, TO (reprint author), Univ Calif Los Angeles, Dept Chem & Biochem, Box 951569, Los Angeles, CA 90095 USA. RI Boutz, Daniel/M-4872-2013; OI Boutz, Daniel/0000-0001-7462-4105; Yeates, Todd/0000-0001-5709-9839; Sawaya, Michael/0000-0003-0874-9043 FU NIA NIH HHS [AG18000]; NIGMS NIH HHS [GM26020, GMO7185] NR 61 TC 38 Z9 39 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD NOV 9 PY 2001 VL 313 IS 5 BP 1103 EP 1116 DI 10.1006/jmbi.2001.5095 PG 14 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 492YN UT WOS:000172195300015 PM 11700066 ER PT J AU Benoit, J Saxena, A Lookman, T AF Benoit, J Saxena, A Lookman, T TI Bogomol'nyi decomposition for vesicles of arbitrary genus SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article ID TOPOLOGICAL SOLITONS; BENDING STIFFNESS; HEISENBERG SPINS; LIPID BILAYERS; CURVATURE; SURFACES; WILLMORE; SECTION AB We apply the Bogomol'nyi technique, which is usually invoked in the study of solitons or models with topological invariants, to the case of elastic energy of vesicles. We show that the spontaneous bending contribution caused by any deformation from metastable bending shapes falls into two distinct topological sets: shapes of spherical topology and shapes of non-spherical topology experience respectively a deviatoric bending contribution a la Fischer and a mean curvature bending contribution, la Helfrich. In other words, topology may be considered to describe bending phenomena. Besides, we calculate the bending energy per genus and the bending closure energy regardless of the shape of the vesicle. As an illustration we briefly consider geometrical frustration phenomena experienced by magnetically coated vesicles. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Cergy Pontoise, Lab Phys Theor & Modelisat, CNRS, ESA 8089, F-95031 Cergy Pontoise, France. RP Benoit, J (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 32 TC 5 Z9 5 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD NOV 9 PY 2001 VL 34 IS 44 BP 9417 EP 9423 DI 10.1088/0305-4470/34/44/306 PG 7 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 497RH UT WOS:000172468900012 ER PT J AU Brisbin, IL Mayer, JJ AF Brisbin, IL Mayer, JJ TI Problem pigs in a poke: A good pool of data SO SCIENCE LA English DT Letter C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. Westinghouse Savannah River Co, Environm Protect Dept, Aiken, SC 29808 USA. RP Brisbin, IL (reprint author), Savannah River Ecol Lab, Aiken, SC 29802 USA. NR 6 TC 4 Z9 4 U1 0 U2 2 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 NOV 9 PY 2001 VL 294 IS 5545 BP 1280 EP 1281 DI 10.1126/science.294.5545.1280 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 491VF UT WOS:000172130200024 PM 11702791 ER PT J AU Wang, XB Yang, X Nicholas, JB Wang, LS AF Wang, XB Yang, X Nicholas, JB Wang, LS TI Bulk-like features in the photoemission spectra of hydrated doubly charged anion clusters SO SCIENCE LA English DT Article ID PHOTODETACHMENT PHOTOELECTRON-SPECTROSCOPY; WATER CLUSTERS; AQUEOUS-SOLUTIONS; LIQUID WATER; AB-INITIO; SOLVATION; ELECTRON; DYNAMICS; STABILIZATION; IONS AB We produced gaseous hydrated clusters of sulfate and oxalate anions [SO42-- (H2O)(n) and C2O42-(H2O)(n) where n = 4 to 40]. Photoelectron spectra of these clusters revealed that the solute dianions were in the center of the water cluster, (H2O)(n) For small clusters, these spectra were characteristic of the respective solutes, but beyond the first solvation shell (n approximate to 12), features in the spectra from the solutes were diminished and a new feature from ionization of water emerged, analogous to bulk aqueous solutions. For large clusters with dimensions greater than 1 nanometer, the solute photoemission features disappeared and the spectra were dominated by the ionization of water as the solvent coverage increased. A smooth transition from gas-phase clusters to behavior of electrolyte solutions was clearly revealed, and the large solvated clusters can be used as molecular models to investigate the photophysics and chemistry of aqueous electrolyte solutions. C1 Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Genentech Inc, San Francisco, CA 94080 USA. RP Wang, LS (reprint author), Washington State Univ, Dept Phys, 2710 Univ Dr, Richland, WA 99352 USA. NR 35 TC 137 Z9 139 U1 2 U2 34 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 NOV 9 PY 2001 VL 294 IS 5545 BP 1322 EP 1325 DI 10.1126/science.1064916 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 491VF UT WOS:000172130200043 PM 11701923 ER PT J AU Mitchell, JF Argyriou, DN Berger, A Gray, KE Osborn, R Welp, U AF Mitchell, JF Argyriou, DN Berger, A Gray, KE Osborn, R Welp, U TI Spin, charge, and lattice states in layered magnetoresistive oxides SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID LA1.2SR1.8MN2O7 SINGLE-CRYSTALS; X-RAY-SCATTERING; PHASE-SEPARATION; DOUBLE-EXCHANGE; NEUTRON-DIFFRACTION; MANGANESE OXIDES; PEROVSKITE-TYPE; COLOSSAL MAGNETORESISTANCE; GIANT MAGNETORESISTANCE; CMR MANGANITES AB Colossal magnetoresistive materials are perovskite-related mixed-valent (Mn3+/Mn4+) manganese oxides that exhibit both spontaneous (at a Curie transition) and magnetic field-induced insulator-metal transitions. In concert with the dramatic changes in electrical conductivity, these oxides exhibit large lattice anomalies, ferro- and antiferromagnetism, charge ordering of the Mn3+/Mn4+ sites, etc. In this article, we discuss how a particular class of these manganite materials, naturally layered manganites La2-2xSr1+2xMn2O7, has allowed us to experimentally probe many of these tightly coupled phenomena. In particular, we examine the structure-property relationships that determine the critical magnetic ground states, we discuss how conductivity and its field dependence can test prevailing models for the magnetoresistance effect, and we explore the interplay and competition between charge- and magnetic-order on both long- and short range length scales. Finally, we present evidence from neutron and X-ray scattering that these short range charge correlations are essential to the mechanism of colossal magnetoresistance in naturally layered manganites. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Mitchell, JF (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Osborn, Raymond/E-8676-2011; Berger, Andreas/D-3706-2015 OI Osborn, Raymond/0000-0001-9565-3140; Berger, Andreas/0000-0001-5865-6609 NR 92 TC 67 Z9 67 U1 0 U2 16 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 NOV 8 PY 2001 VL 105 IS 44 BP 10731 EP 10745 DI 10.1021/jp011419u PG 15 WC Chemistry, Physical SC Chemistry GA 490JQ UT WOS:000172049100001 ER PT J AU Hsu, CP Walla, PJ Head-Gordon, M Fleming, GR AF Hsu, CP Walla, PJ Head-Gordon, M Fleming, GR TI The role of the S(1) state of carotenoids in photosynthetic energy transfer: The light-harvesting complex II of purple bacteria SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID DENSITY-FUNCTIONAL THEORY; EXCITATION-ENERGIES; ANTENNA COMPLEX; AB-INITIO; RHODOPSEUDOMONAS-ACIDOPHILA; RHODOBACTER-SPHAEROIDES; TO-BACTERIOCHLOROPHYLL; FEMTOSECOND DYNAMICS; CRYSTAL-STRUCTURE; RESPONSE THEORY AB Using time-dependent density functional theory (TDDFT), we obtained the excitation energy transfer coupling (Coulombic coupling) between the S(1) state of rhodopin glucoside (RG) and the Q(y) state of bacteriochlorophylls (BCh1) in the light-harvesting complex II (LH2) of purple photosynthetic bacterium Rhodopseudomonas (Rps.) acidophila. Our results suggest that the small mixing of S(2) character arising from symmetry-breaking of the carotenoid plays an important role in the Coulombic coupling. As a result the carotenoid (car) S(1) couplings to chlorophylls are similar to a set of scaled down Car(S2)-BCh1(Q(y)) couplings. We also report results for 6,10,15,19-tetramethyl-2-cis-4,6,8,10,12,14,16,18,20-all trans-22-cis-tetracosaundecaene, the polyene backbone of RG with six methyl groups attached, in two different structures: an optimized planar structure and the crystal structure of RG with hydrogen atoms replacing the two end groups, which is distorted from its planar structure. The mixing of S(2) configuration is strictly forbidden in the planar structure due to symmetry. In this case the polyene still couples moderately strongly to the nearby BCh1s. In the distorted structure derived from RG crystal structure, coupling strengths and the role of S(2) character mixing are similar to those of the full RG. Using an exciton model simulation, the calculated coupling strengths yield Car(S(1))-to-BCh1(Q(y)) excitation energy transfer times that are in good agreement with recent experimental results. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Fleming, GR (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Hsu, Chao-Ping/E-1303-2011 OI Hsu, Chao-Ping/0000-0002-7187-427X NR 57 TC 78 Z9 79 U1 0 U2 10 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 NOV 8 PY 2001 VL 105 IS 44 BP 11016 EP 11025 DI 10.1021/jp0119835 PG 10 WC Chemistry, Physical SC Chemistry GA 490JQ UT WOS:000172049100037 ER PT J AU Resat, H Wiley, HS Dixon, DA AF Resat, H Wiley, HS Dixon, DA TI Probability-weighted dynamic Monte Carlo method for reaction kinetics simulations SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID EXACT STOCHASTIC SIMULATION; COUPLED CHEMICAL-REACTIONS; RECEPTOR; SYSTEMS AB The reaction kinetics underlying the dynamic features of physical systems can be investigated by using various approaches such as the Dynamic Monte Carlo (DMC) method. The usefulness of the DMC method to study reaction kinetics has been limited to systems where the underlying reactions occur with similar frequencies, i.e., similar rate constants. However, many interesting physical phenomena involve sets of reactions with a wide range of rate constants leading to a broad range of relevant time scales. Widely varying reaction rates result in a highly skewed reaction occurrence probability distribution. When the reaction occurrence probability distribution has a wide spectrum, the reactions with faster rates dominate the computations, making the reliable statistical sampling cumbersome. We have developed a probability-weighted DMC method by incorporating the weighted sampling algorithm of equilibrium molecular simulations. This new algorithm samples the slow reactions very efficiently and makes it possible to simulate in a computationally efficient manner the reaction kinetics of physical systems in which the rates of reactions vary by several orders of magnitude. We validate the probability-weighted DMC algorithm by applying it to two model systems: a simple chemical reaction system and a model of vesicular trafficking in living cells. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, POB 999,Mail Stop K1-83, Richland, WA 99352 USA. EM haluk.resat@pnl.gov OI Wiley, Steven/0000-0003-0232-6867 NR 17 TC 43 Z9 45 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD NOV 8 PY 2001 VL 105 IS 44 BP 11026 EP 11034 DI 10.1021/jp011404w PG 9 WC Chemistry, Physical SC Chemistry GA 490JQ UT WOS:000172049100038 ER PT J AU Plehn, T Rainwater, D AF Plehn, T Rainwater, D TI Higgs decays to muons in weak boson fusion SO PHYSICS LETTERS B LA English DT Article ID CERN LHC; SECTOR; MASS AB We investigate the muonic decay of a light Higgs boson, produced in weak boson fusion at future hadron colliders. We find that this decay mode would be observable at the CERN LHC only with an unreasonably large amount of data, while at a 200 TeV vLHC this process could be used to extract the muon Yukawa coupling to about the 10%, level, or better if significant improvements in detector design can be achieved. (C) 2001 Published by Elsevier Science B.V. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Fermilab Natl Accelerator Lab, Theory Dept, Batavia, IL 60510 USA. RP Plehn, T (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. OI rainwater, david/0000-0002-3668-4331 NR 23 TC 32 Z9 32 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 NOV 8 PY 2001 VL 520 IS 1-2 BP 108 EP 114 DI 10.1016/S0370-2693(01)01157-1 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 488GN UT WOS:000171928000015 ER PT J AU Liu, TB Wan, Q Xie, Y Burger, C Liu, LZ Chu, B AF Liu, TB Wan, Q Xie, Y Burger, C Liu, LZ Chu, B TI Polymer-assisted formation of giant polyoxomolybdate structures SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TRIBLOCK COPOLYMER; CRYSTAL-STRUCTURE; METAL-OXIDES; MOLYBDENUM; ASSEMBLIES; REFINEMENT; OXIDATION; CHEMISTRY; TEMPLATE; TIO2 AB A highly ordered, porous nanoscale network structure of polyoxomolybdate was prepared from the slow decomposition of an unstable precursor compound MoO2(OH)(OOH) in the presence of PEO-containing triblock copolymer gels or sernidilute/concentrated poly(ethylene oxide) (PEO) homopolymer solutions. Small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) measurements of the 1-mum size crystals revealed an extremely ordered primitive cubic (pc) structure made of polyoxomolybdates. Scanning electron microscopy (SEM) measurements showed that the overall size of these single crystals was close to 1 mum, in agreement with estimates from the scattering peak widths. Evidence from both scattering measurements and transmission electron microscope (TEM) measurements suggested that the system formed a highly porous primitive cubic network similar to that of certain zeolite structures. However, the observed lattice constant of 5 nm was much larger. The function of the PEO-containing polymer network was found to be very subtle and complex. Presumably, PEO acted simultaneously as a weak reducing agent and as a viscous matrix to ensure sufficient time for the formation of long-range ordered structures, resulting in the growth of extremely uniform but probably hollow "nanospheres". We suggest that this new material may find unique applications as a high-efficiency absorbent or catalyst. Furthermore, the current synthetic method may open up new pathways to prepare similar functional nanomaterials. C1 SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. Univ Sci & Technol China, Dept Chem, Hefei 230026, Anhui, Peoples R China. RP Chu, B (reprint author), SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. RI Liu, Tianbo/D-8915-2017 OI Liu, Tianbo/0000-0002-8181-1790 NR 33 TC 31 Z9 32 U1 1 U2 18 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 NOV 7 PY 2001 VL 123 IS 44 BP 10966 EP 10972 DI 10.1021/ja010366r PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 490JR UT WOS:000172049200022 PM 11686700 ER PT J AU Ghosh, T Garcia, AE Garde, S AF Ghosh, T Garcia, AE Garde, S TI Molecular dynamics simulations of pressure effects on hydrophobic interactions SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID TRANSFORM INFRARED-SPECTROSCOPY; X-RAY-SCATTERING; LIQUID WATER; FREE-ENERGY; PROTEIN; METHANE; DEPENDENCE; HYDRATION; ENTROPY; MODEL AB We report results on the pressure effects on hydrophobic interactions obtained from molecular dynamics simulations of aqueous solutions of methanes in water. A wide range of pressures that is relevant to pressure denaturation of proteins is investigated. The characteristic features of water-mediated interactions between hydrophobic solutes are found to be pressure-dependent. In particular, with increasing pressure we find that (1) the solvent-separated configurations in the solute-solute potential of mean force (PMF) are stabilized with respect to the contact configurations; (2) the desolvation barrier increases monotonically with respect to both contact and solvent-separated configurations; (3) the locations of the minima and the barrier move toward shorter separations; and (4) pressure effects are considerably amplified for larger hydrophobic solutes. Together, these observations lend strong support to the picture of the pressure denaturation process proposed previously by Hummer et al. (Proc. Natl. Acad. Sci. U.S.A. 1998, 95, 1552): with increasing pressure, the transfer of water into protein interior becomes key to the pressure denaturation process, leading to-the dissociation of close hydrophobic contacts and subsequent swelling of the hydrophobic protein interior through insertions of water molecules. The pressure dependence of the PMF between larger hydrophobic solutes shows that pressure effects on the interaction between hydrophobic amino acids may be considerably amplified compared to those on the methane-methane PMF. C1 Rensselaer Polytech Inst, Dept Chem Engn, Troy, NY 12180 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Garde, S (reprint author), Rensselaer Polytech Inst, Dept Chem Engn, Troy, NY 12180 USA. RI Garde, Shekhar/C-3060-2008 NR 52 TC 94 Z9 94 U1 0 U2 26 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 NOV 7 PY 2001 VL 123 IS 44 BP 10997 EP 11003 DI 10.1021/ja010446v PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 490JR UT WOS:000172049200026 PM 11686704 ER PT J AU Skurski, P Rak, J Simons, J Gutowski, M AF Skurski, P Rak, J Simons, J Gutowski, M TI Quasidegeneracy of zwitterionic and canonical tautomers of arginine solvated by an excess electron SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID GAS-PHASE C1 Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. Univ Utah, Dept Chem, Henry Eyring Ctr Theoret Chem, Salt Lake City, UT 84112 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Gutowski, M (reprint author), Univ Gdansk, Dept Chem, Ul Sobieskiego 18, PL-80952 Gdansk, Poland. NR 20 TC 59 Z9 59 U1 1 U2 4 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 NOV 7 PY 2001 VL 123 IS 44 BP 11073 EP 11074 DI 10.1021/ja011358d PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 490JR UT WOS:000172049200039 PM 11686717 ER PT J AU Boehlert, CJ Schulze, RK Mitchell, JN Zocco, TG Pereyra, RA AF Boehlert, CJ Schulze, RK Mitchell, JN Zocco, TG Pereyra, RA TI Initial electron backscattered diffraction observations of a plutonium alloy SO SCRIPTA MATERIALIA LA English DT Article DE electron backscattered diffraction; plutonium; microstructure; ion sputtering; scanning electron microscopy AB In this work, the first electron backscattered diffraction patterns (EBSPs) were captured for a plutonium-gallium. (Pu-Ga) alloy. The experimental techniques used for EBSP acquisition are described in detail. This demonstrated sample preparation and characterization technique is expected to be a powerful means to further understand phase transformation behavior, orientation relationships, and texture in the complicated Pu and Pu-alloy systems. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Alfred Univ, Sch Ceram Engn & Mat Sci, Alfred, NY 14802 USA. Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RP Boehlert, CJ (reprint author), Alfred Univ, Sch Ceram Engn & Mat Sci, 2 Pine St, Alfred, NY 14802 USA. RI Mitchell, Jeremy/E-2875-2010 OI Mitchell, Jeremy/0000-0001-7109-3505 NR 7 TC 7 Z9 7 U1 1 U2 3 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 NOV 7 PY 2001 VL 45 IS 9 BP 1107 EP 1115 DI 10.1016/S1359-6462(01)01136-8 PG 9 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 490AF UT WOS:000172025200015 ER PT J AU Krishnan, VV Thornton, KH Thelen, MP Cosman, M AF Krishnan, VV Thornton, KH Thelen, MP Cosman, M TI Solution structure and backbone dynamics of the human DNA ligase III alpha BRCT domain SO BIOCHEMISTRY LA English DT Article ID BASE EXCISION-REPAIR; CRYSTAL-STRUCTURE; POLYMERASE-BETA; POLY(ADP-RIBOSE) POLYMERASE; MEIOTIC RECOMBINATION; MOLECULAR-CLONING; NMR-SPECTROSCOPY; PROTEIN XRCC1; RESOLUTION; SPECTRA AB (BRCA1 carboxyl terminus) domains are found in a number of DNA repair enzymes and cell cycle regulators and are believed to mediate important protein-protein interactions. The DNA ligase III alpha BRCT domain partners with the distal BRCT domain of the DNA repair protein XRCC1 (X1BRCTb) in the DNA base excision repair (BER) pathway. To elucidate the mechanisms by which these two domains can interact, we have determined the solution structure of human ligase III alpha BRCT (L3[86], residues 837-922). The structure of L3[86] consists of a beta2 beta1 beta3 beta4 parallel sheet with a two-a-helix bundle packed against one face of the sheet. This fold is conserved in several proteins having a wide range of activities, including X1BRCTb [Zhang, X. D., et al. (1998) EMBO J. 17, 6404-6411]. L3[86] exists as a dimer in solution, but an insufficient number of NOE restraints precluded the determination of the homodimer structure. However, C-13 isotope-filtered and hydrogen-deuterium exchange experiments indicate that the N-terminus, alpha1, the alpha1-beta2 loop, and the three residues following alpha2 are involved in forming the dimer interface, as similarly observed in the structure of X1BRCTb. NOE and dynamic data indicate that several residues (837-844) in the N-terminal region appear to interconvert between helix and random coil conformations. Further studies of other BRCT domains and of their complexes are needed to address how these proteins interact with one another, and to shed light on how mutations can lead to disruption of function and ultimately disease. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Cosman, M (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RI Thelen, Michael/C-6834-2008; Krishnan, Krish/A-6859-2010; Thelen, Michael/G-2032-2014 OI Thelen, Michael/0000-0002-2479-5480; Thelen, Michael/0000-0002-2479-5480 FU NCI NIH HHS [CA76116] NR 54 TC 39 Z9 39 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD NOV 6 PY 2001 VL 40 IS 44 BP 13158 EP 13166 DI 10.1021/bi010979g PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 490NC UT WOS:000172057100005 PM 11683624 ER PT J AU McGrath, WJ Baniecki, ML Li, C McWhirter, SM Brown, MT Toledo, DL Mangel, WF AF McGrath, WJ Baniecki, ML Li, C McWhirter, SM Brown, MT Toledo, DL Mangel, WF TI Human adenovirus proteinase: DNA binding and stimulation of proteinase activity by DNA SO BIOCHEMISTRY LA English DT Article ID CRYSTAL-STRUCTURE; PROTEASE; TYPE-2; ACTIVATION; COFACTORS; PEPTIDE AB The interaction of the human adenovirus proteinase (AVP) with various DNAs was characterized. AVP requires two cofactors for maximal activity, the 11-amino acid residue peptide from the C-terminus of adenovirus precursor protein pVI (pVIc) and the viral DNA. DNA binding was monitored by changes in enzyme activity or by fluorescence anisotropy. The equilibrium dissociation constants for the binding of AVP and AVP-pVIc complexes to 12-mer double-stranded (ds) DNA were 63 and 2.9 nM, respectively. DNA binding was not sequence specific; the stoichiometry of binding was proportional to the length of the DNA. Three molecules of the AVP-pVIc complex bound to 18-mer dsDNA and six molecules to 36-mer dsDNA. When AVP-pVIc complexes bound to 12-mer dsDNA, two sodium ions were displaced from the DNA. A DeltaG(0)(0) of -4.6 kcal for the nonelectrostatic free energy of binding indicated that a substantial component of the binding free energy results from nonspecific interactions between the AVP-pVIc complex and DNA. The cofactors altered the interaction of the enzyme with the fluorogenic substrate (Leu-Arg-Gly-Gly-NH)(2)-rhodamine. In the absence of any cofactor, the K-m was 94.8 muM and the kcal was 0.002 s(-1). In the presence of adenovirus DNA, the Km decreased 10-fold and the k(cat) increased 11-fold. In the presence of pVIc, the K-m decreased 10-fold and the k(cat) increased 118-fold. With both cofactors present, the k(cat)/K-m ratio increased 34000-fold, compared to that with AVP alone. Binding to DNA was coincident with stimulation of proteinase activity by DNA. Although other proteinases have been shown to bind to DNA, stimulation of proteinase activity by DNA is unprecedented. A model is presented suggesting that AVP moves along the viral DNA looking for precursor protein cleavage sites much like RNA polymerase moves along DNA looking for a promoter. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. SUNY Stony Brook, Dept Pharmacol Sci, Stony Brook, NY 11794 USA. RP Mangel, WF (reprint author), Brookhaven Natl Lab, Dept Biol, 50 Bell Ave,POB 5000, Upton, NY 11973 USA. FU NIAID NIH HHS [AI41599] NR 24 TC 28 Z9 29 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD NOV 6 PY 2001 VL 40 IS 44 BP 13237 EP 13245 DI 10.1021/bi0111653 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 490NC UT WOS:000172057100013 PM 11683632 ER PT J AU Wignall, GD Alamo, RG Ritchson, EJ Mandelkern, L Schwahn, D AF Wignall, GD Alamo, RG Ritchson, EJ Mandelkern, L Schwahn, D TI SANS studies of liquid-liquid phase separation in heterogeneous and metallocene-based linear low-density polyethylenes SO MACROMOLECULES LA English DT Article ID SMALL-ANGLE NEUTRON; DIFFERENTIAL SCANNING CALORIMETRY; SATURATED-HYDROCARBON POLYMERS; X-RAY-SCATTERING; BRANCHED POLYETHYLENES; RANDOM COPOLYMERS; MOLECULAR-WEIGHT; BLENDS; BEHAVIOR; THERMODYNAMICS AB An ethylene-hexene copolymer, representative of many heterogeneous linear low-density polyethylenes (LLDPEs), has been shown to contain a dispersed minority phase (volume fraction similar to 10(-2).), which was manifested by departures from a Q(-2) variation of the neutron scattering cross section at low Q values. After xylene extraction, which removes the highly branched amorphous material, the dispersed phase is removed to a good approximation. In contrast, a metallocene-based LLDPE, which has a more homogeneous distribution of branch contents, does not exhibit an upturn in the cross section in the limit of low momentum transfer (Q < 10(-2) Angstrom (-1)), indicating that the LLDPE forms only a single phase in the melt. The composition variance is calculated from the comonomer composition distribution obtained by temperature-rising elution fractionation (TREF) and used to estimate proximity of the melts to the spinodal condition. These findings support previous conclusions for compositionally polydisperse LLDPEs, whereby the highly branched molecules in the distribution may phase segregate, even if the overall branch content is low. When this component is not present, as in metallocene-based LLDPEs, the system forms a single phase in the melt. C1 Florida A&M Univ, Dept Chem Engn, Tallahassee, FL 32310 USA. Florida State Univ, Coll Engn, Tallahassee, FL 32310 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Florida State Univ, Dept Chem, Tallahassee, FL 32306 USA. Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. RP Florida A&M Univ, Dept Chem Engn, Tallahassee, FL 32310 USA. OI Wignall, George/0000-0002-3876-3244 NR 37 TC 34 Z9 36 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 EI 1520-5835 J9 MACROMOLECULES JI Macromolecules PD NOV 6 PY 2001 VL 34 IS 23 BP 8160 EP 8165 DI 10.1021/ma010697o PG 6 WC Polymer Science SC Polymer Science GA 489FN UT WOS:000171981500035 ER PT J AU Androsch, R Wunderlich, B AF Androsch, R Wunderlich, B TI Heat of fusion of the local equilibrium of melting of isotactic polypropylene SO MACROMOLECULES LA English DT Article; Proceedings Paper CT 29th Annual Conference of the North-American-Thermal-Analysis-Society_(NATAS) CY SEP 24-26, 2001 CL ST LOUIS, MISSOURI SP N Amer Therm Analy Soc ID X-RAY-SCATTERING; CAPACITY MEASUREMENTS; MODULATED DSC; TEMPERATURE; CRYSTALLIZATION; POLYETHYLENE; MODEL C1 Univ Halle Wittenberg, Inst Sci Mat, D-06217 Merseburg, Germany. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Androsch, R (reprint author), Univ Halle Wittenberg, Inst Sci Mat, Geusaer Str, D-06217 Merseburg, Germany. NR 22 TC 14 Z9 14 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD NOV 6 PY 2001 VL 34 IS 23 BP 8384 EP 8387 DI 10.1021/ma011118i PG 4 WC Polymer Science SC Polymer Science GA 489FN UT WOS:000171981500063 ER PT J AU Barenblatt, GI AF Barenblatt, GI TI Self-similar intermediate asymptotics for nonlinear degenerate parabolic free-boundary problems that occur in image processing SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE nonlinear partial differential equations; self-similar solutions ID EDGE-DETECTION; DIFFUSION; CURVATURE; EQUATION AB In the boundary layers around the edges of images, basic nonlinear parabolic equations for image intensity used in image processing assume a special degenerate asymptotic form. An asymptotic self-similar solution to this degenerate equation is obtained in an explicit form. The solution reveals a substantially nonlinear effect-the formation of sharp steps at the edges of the images, leading to edge enhancement. Positions of the steps and the time shift parameter cannot be determined by direct construction of a self-similar solution; they depend on the initial condition of the pre-self-similar solution. The free-boundary problem is formulated describing the image intensity evolution in the boundary layer. C1 Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Barenblatt, GI (reprint author), Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. NR 8 TC 6 Z9 6 U1 0 U2 2 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 NOV 6 PY 2001 VL 98 IS 23 BP 12878 EP 12881 DI 10.1073/pnas.241501698 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 490WM UT WOS:000172076800011 PM 11606792 ER PT J AU Bonanno, JB Edo, C Eswar, N Pieper, U Romanowski, MJ Ilyin, V Gerchman, SE Kycia, H Studier, FW Sali, A Burley, SK AF Bonanno, JB Edo, C Eswar, N Pieper, U Romanowski, MJ Ilyin, V Gerchman, SE Kycia, H Studier, FW Sali, A Burley, SK TI Structural genomics of enzymes involved in sterol/isoprenoid biosynthesis SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID MEVALONATE; CRYSTALLOGRAPHY; DIFFRACTION; EVOLUTION; ALIGNMENT; DATABASE; PROGRAMS; PROTEINS; SOFTWARE; MATRICES AB X-ray structures of two enzymes in the sterol/isoprenoid blosynthesis pathway have been determined in a structural genomics pilot study. Mevalonate-5-diphosphate clecarboxylase (MDD) is a single-domain alpha/beta protein that catalyzes the last of three sequential ATP-depenclent reactions which convert mevalonate to isopentenyl diphosphate. Isopentenyl disphosphate isomerase (IDI) is an alpha/beta metalloenzyme that catalyzes interconversion of isopentenyl diphosphate and dimethylallyl diphosphate, which condense in the next step toward synthesis of sterols and a host of natural products. Homology modeling of related proteins and comparisons of the MIDD and IDI structures with two other experimentally determined structures have shown that MDD is a member of the GHMP superfamily of small-molecule kinases and IDI is similar to the nudix hydrolases, which act on nucleotide diphosphate-containing substrates. Structural models were produced for 379 proteins, encompassing a substantial fraction of both protein superfamilies. All three enzymes responsible for synthesis of isopentenyl diphosphate from mevalonate (mevalonate kinase, phosphomevalonate kinase, and MDD) share the same fold, catalyze phosphorylation of chemically similar substrates (MDD decarboxylation involves phosphorylation of mevalonate diphosphate), and seem to have evolved from a common ancestor. These structures and the structural models derived from them provide a framework for interpreting biochemical function and evolutionary relationships. C1 Rockefeller Univ, Labs Mol Biophys, New York, NY 10021 USA. Rockefeller Univ, Howard Hughes Med Inst, New York, NY 10021 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Burley, SK (reprint author), Rockefeller Univ, Labs Mol Biophys, 1230 York Ave, New York, NY 10021 USA. RI Pieper, Ursula/E-4444-2010 FU NIGMS NIH HHS [R29 GM5462, P50 GM62529, P50 GM062529, R29 GM054762] NR 40 TC 87 Z9 91 U1 0 U2 6 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 NOV 6 PY 2001 VL 98 IS 23 BP 12896 EP 12901 DI 10.1073/pnas.181466998 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 490WM UT WOS:000172076800015 PM 11698677 ER PT J AU Cantoni, C Christen, DK Feenstra, R Goyal, A Ownby, GW Zehner, DM Norton, DP AF Cantoni, C Christen, DK Feenstra, R Goyal, A Ownby, GW Zehner, DM Norton, DP TI Reflection high-energy electron diffraction studies of epitaxial oxide seed-layer growth on rolling-assisted biaxially textured substrate Ni(001): The role of surface structure and chemistry SO APPLIED PHYSICS LETTERS LA English DT Article ID OXYGEN; CHEMISORPTION; SULFUR; NICKEL; FILMS; NI; NI(100); XPS AB We present a study of the {100}< 100 > biaxially textured Ni(001) surface and seed-layer growth using in situ reflection high-energy electron diffraction and Auger electron spectroscopy. Our observations are consistent with formation of a c(2x2) two-dimensional superstructure due to the surface segregation of sulfur contained in the metal. We show that this superstructure can have a dramatic effect on the heteroepitaxial growth of oxide seed layers. In particular, the surface superstructure promotes the (200) epitaxial oxide growth of Y2O3-stabilized ZrO2, which is necessary for the development of high-J(c) superconducting films for coated conductors. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. RP Cantoni, C (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Cantoni, Claudia/G-3031-2013 OI Cantoni, Claudia/0000-0002-9731-2021 NR 14 TC 36 Z9 39 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 5 PY 2001 VL 79 IS 19 BP 3077 EP 3079 DI 10.1063/1.1407857 PG 3 WC Physics, Applied SC Physics GA 487UY UT WOS:000171896600021 ER PT J AU Heck, S Branz, HM AF Heck, S Branz, HM TI Fingerprints of two distinct defects causing light-induced photoconductivity degradation in hydrogenated amorphous silicon SO APPLIED PHYSICS LETTERS LA English DT Article ID A-SI-H; DRIFT MOBILITY; PHOTOCURRENT; ABSORPTION AB We find distinct experimental fingerprints of two metastable defects created during illumination of hydrogenated amorphous silicon. The well-studied threefold-coordinated silicon dangling bond defect has an anneal activation energy near 1.1 eV and dominates annealing experiments above about 110 degreesC. The second defect created by illumination is the "primary recombination" (pr) center, which causes most of the light-induced photoconductivity decrease and dominates annealing experiments below about 110 degreesC. Because the pr centers are created in linear proportion to the dangling bond defects, they are difficult to distinguish during degradation. However, we observe clear fingerprints of the pr center during their low T annealing: (1) an anneal activation energy of 0.85 eV; (2) a sharp increase in photoconductivity; and (3) a surprising increase in h nu less than or equal to1.1 eV optical absorption. (C) 2001 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Heck, S (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 19 TC 11 Z9 11 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 5 PY 2001 VL 79 IS 19 BP 3080 EP 3082 DI 10.1063/1.1413719 PG 3 WC Physics, Applied SC Physics GA 487UY UT WOS:000171896600022 ER PT J AU Stemmer, S Hoche, T Keding, R Russel, C Schneider, R Browning, ND Streiffer, SK Kleebe, HJ AF Stemmer, S Hoche, T Keding, R Russel, C Schneider, R Browning, ND Streiffer, SK Kleebe, HJ TI Oxidation states of titanium in bulk barium titanates and in (100) fiber-textured (BaxSr1-x)Ti1+yO3+z thin films SO APPLIED PHYSICS LETTERS LA English DT Article ID ELECTRON-ENERGY-LOSS; CHEMICAL-VAPOR-DEPOSITION; STRONTIUM-TITANATE; LOSS SPECTROSCOPY; COMPUTER-SIMULATION; SRTIO3; DEFECT; OXIDES; EDGES; TI AB Chemical shifts of titanium L edges and oxygen K edges in electron energy-loss spectroscopy in transmission electron microscopy were used to detect valence state reduction of Ti in bulk barium titanates, used as reference materials, and in (BaxSr1-x)Ti1+yO3+z (BST) thin films grown with excess Ti. A hollandite-type Ba titanate, containing Ti with an average valence state of approximately 3.7 in octahedral coordination, showed large chemical shifts relative to rutile TiO2 and BaTiO3, containing only Ti4+. In BST, chemical shifts relative to BaTiO3 were measured from grain interiors of columnar films with different amounts of excess Ti. We found that shifts, corresponding to an average valence state of Ti smaller than nominal 4+, increase with increasing amounts of excess Ti in the films. The results show that at least some amount of excess Ti is accommodated in these films by a defect mechanism that requires a reduction of the average valence state of Ti. (C) 2001 American Institute of Physics. C1 Rice Univ, Dept Mech Engn & Mat Sci, Houston, TX 77005 USA. Univ Jena, Otto Schott Inst, D-07743 Jena, Germany. Humboldt Univ, Inst Phys, D-10115 Berlin, Germany. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Colorado Sch Mines, Dept Met & Mat Engn, Golden, CO 80401 USA. RP Stemmer, S (reprint author), Rice Univ, Dept Mech Engn & Mat Sci, Houston, TX 77005 USA. RI Streiffer, Stephen/A-1756-2009; Stemmer, Susanne/H-6555-2011; Hoche, Thomas/J-7850-2012; Kleebe, Hans-Joachim/C-5709-2016 OI Stemmer, Susanne/0000-0002-3142-4696; NR 29 TC 6 Z9 7 U1 2 U2 8 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 5 PY 2001 VL 79 IS 19 BP 3149 EP 3151 DI 10.1063/1.1418036 PG 3 WC Physics, Applied SC Physics GA 487UY UT WOS:000171896600045 ER PT J AU Lopez, R Boatner, LA Haynes, TE Haglund, RF Feldman, LC AF Lopez, R Boatner, LA Haynes, TE Haglund, RF Feldman, LC TI Enhanced hysteresis in the semiconductor-to-metal phase transition of VO2 precipitates formed in SiO2 by ion implantation SO APPLIED PHYSICS LETTERS LA English DT Article ID INSULATOR; SAPPHIRE AB A strongly enhanced hysteresis with a width of > 34 degreesC has been observed in the semiconductor-to-metal phase transition of submicron-scale VO2 precipitates formed in the near-surface region of amorphous SiO2 by the stoichiometric coimplantation of vanadium and oxygen and subsequent thermal processing. This width is approximately an order of magnitude larger than that reported previously for the phase transition of VO2 particles formed in Al2O3 by a similar technique. The phase transition is accompanied by a significant change in infrared transmission. The anomalously wide hysteresis loop observed here for the VO2/SiO2 system can be exploited in optical data storage and switching applications in the infrared region. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RP Lopez, R (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Lopez, Rene/G-3734-2014; Haynes, Tony/P-8932-2015; Boatner, Lynn/I-6428-2013 OI Lopez, Rene/0000-0001-6274-066X; Haynes, Tony/0000-0003-2871-4745; Boatner, Lynn/0000-0002-0235-7594 NR 19 TC 75 Z9 75 U1 5 U2 35 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 5 PY 2001 VL 79 IS 19 BP 3161 EP 3163 DI 10.1063/1.1415768 PG 3 WC Physics, Applied SC Physics GA 487UY UT WOS:000171896600049 ER PT J AU Giesbrecht, GR Shafir, A Arnold, J AF Giesbrecht, GR Shafir, A Arnold, J TI Synthesis and structure of a linked-bis(amidate) ligand and some complexes with titanium SO INORGANIC CHEMISTRY LA English DT Article ID EARLY TRANSITION-METALS; LOW-VALENT CHEMISTRY; BENZAMIDINATE LIGANDS; ALKYL DERIVATIVES; SCHIFF-BASE; ZIRCONIUM; ISOCYANATES; CATALYSTS; FORM C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Arnold, J (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Shafir, Alexandr/D-1676-2009; Arnold, John/F-3963-2012 OI Shafir, Alexandr/0000-0002-8127-2299; Arnold, John/0000-0001-9671-227X NR 32 TC 20 Z9 20 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD NOV 5 PY 2001 VL 40 IS 23 BP 6069 EP 6072 DI 10.1021/ic101533o PG 4 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 488JR UT WOS:000171932500052 PM 11681929 ER PT J AU Mohri, H Perelson, AS Tung, K Ribeiro, RM Ramratnam, B Markowitz, M Kost, R Hurley, A Weinberger, L Cesar, D Hellerstein, MK Ho, DD AF Mohri, H Perelson, AS Tung, K Ribeiro, RM Ramratnam, B Markowitz, M Kost, R Hurley, A Weinberger, L Cesar, D Hellerstein, MK Ho, DD TI Increased turnover of T lymphocytes in HIV-1 infection and its reduction by antiretroviral therapy SO JOURNAL OF EXPERIMENTAL MEDICINE LA English DT Article DE deuterated glucose; longitudinal study; mathematical model; apoptosis; mechanisms of CD4(+) T cell depletion ID PROGRAMMED CELL-DEATH; RAPID TURNOVER; LIFE-SPAN; IN-VIVO; KINETICS; CD4(+); PROLIFERATION; DIVISION; DNA; QUANTIFICATION AB The mechanism of CD4(+) T cell depletion in human immunodeficiency virus (HIV)-1 infection remains controversial. Using deuterated glucose to label the DNA of proliferating cells in vivo, we studied T cell dynamics in four normal subjects and seven HIV-1-infected patients naive to antiretroviral drugs. The results were analyzed using a newly developed mathematical model to determine fractional rates of lymphocyte proliferation and death. In CD4(+) T cells, mean proliferation and death rates were elevated by 6.3- and 2.9-fold, respectively, in infected patients compared with normal controls. In CD8(+) T cells, the mean proliferation rate was 7.7-fold higher in HIV-1 infection, but the mean death rate was not significantly increased. Five of the infected patients underwent subsequent deuterated glucose labeling studies after initiating antiretroviral therapy. The lymphocyte proliferation and death rates in both CD4(+) and CD8(+) cell populations were substantially reduced by 5-11 weeks and nearly normal by one year. Taken together, these new findings strongly indicate that CD4(+) lymphocyte depletion seen in AIDS is primarily a consequence of increased cellular destruction, not decreased cellular production. C1 Rockefeller Univ, Aaron Diamond AIDS Res Ctr, New York, NY 10016 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Dept Nutr Sci, Berkeley, CA 94720 USA. Univ Calif San Francisco, San Francisco Gen Hosp, Dept Med, San Francisco, CA 94110 USA. RP Ho, DD (reprint author), Rockefeller Univ, Aaron Diamond AIDS Res Ctr, 455 1st Ave, New York, NY 10016 USA. FU NIAID NIH HHS [AI40387, P30 AI042848, AI42848] NR 31 TC 238 Z9 244 U1 0 U2 8 PU ROCKEFELLER UNIV PRESS PI NEW YORK PA 1114 FIRST AVE, 4TH FL, NEW YORK, NY 10021 USA SN 0022-1007 J9 J EXP MED JI J. Exp. Med. PD NOV 5 PY 2001 VL 194 IS 9 BP 1277 EP 1287 DI 10.1084/jem.194.9.1277 PG 11 WC Immunology; Medicine, Research & Experimental SC Immunology; Research & Experimental Medicine GA 492GF UT WOS:000172159500009 PM 11696593 ER PT J AU Nicklas, M Borth, R Lengyel, E Pagliuso, PG Sarrao, JL Sidorov, VA Sparn, G Steglich, F Thompson, JD AF Nicklas, M Borth, R Lengyel, E Pagliuso, PG Sarrao, JL Sidorov, VA Sparn, G Steglich, F Thompson, JD TI Response of the heavy-fermion superconductor CeCoIn5 to pressure: roles of dimensionality and proximity to a quantum-critical point SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID METALS; STATES AB We report measurements of the pressure-dependent superconducting transition temperature T-c and electrical resistivity of the heavy-fermion compound CeCoIn5. Pressure moves CeCoIn5 away from its proximity to a quantum-critical point at atmospheric pressure. Experimental results are qualitatively consistent with theoretical predictions for strong-coupled, d-wave superconductivity in an anisotropic three-dimensional superconductor. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Max Planck Inst Chem Phys Solids, D-01187 Dresden, Germany. Russian Acad Sci, Inst High Pressure Phys, Troitsk 142092, Moscow Region, Russia. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Pagliuso, Pascoal/C-9169-2012; Sparn, Guenter/F-5120-2013; Nicklas, Michael/B-6344-2008 OI Nicklas, Michael/0000-0001-6272-2162 NR 31 TC 61 Z9 61 U1 1 U2 9 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 EI 1361-648X J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD NOV 5 PY 2001 VL 13 IS 44 BP L905 EP L912 DI 10.1088/0953-8984/13/44/104 PG 8 WC Physics, Condensed Matter SC Physics GA 494TG UT WOS:000172301500004 ER PT J AU Singleton, J Harrison, N Mielke, CH Schlueter, JA Kini, AM AF Singleton, J Harrison, N Mielke, CH Schlueter, JA Kini, AM TI A statistical model for the intrinsically broad superconducting-to-normal transition in quasi-two-dimensional crystalline organic metals SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID TEMPERATURE AB Although quasi-two-dimensional organic superconductors such as kappa-(BEDT-TTF)(2)Cu(NCS)(2) (BEDT-TTF = bis(ethylene-dithio)tetrathiafulvalene) seem to be very clean systems, with apparent quasiparticle mean free paths of several thousand angstroms, the superconducting transition is intrinsically broad (e.g. similar to1 K wide for T-c approximate to 10 K). We propose that this is due to the extreme anisotropy of these materials, which greatly exacerbates the statistical effects of spatial variations in the potential experienced by the quasiparticles. Using a statistical model, we are able to account for the experimental observations. A parameter (x) over bar which characterizes the spatial potential variations, may be derived from Shubnikov-de Haas oscillation experiments. Using this value, we are able to predict a transition width which is in good agreement with that observed in megahertz penetration-depth measurements on the same sample. C1 Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Singleton, J (reprint author), Los Alamos Natl Lab, Natl High Magnet Field Lab, MS-E536, Los Alamos, NM 87545 USA. RI Kini, Aravinda/F-4467-2012; Mielke, Charles/S-6827-2016 OI Mielke, Charles/0000-0002-2096-5411 NR 23 TC 9 Z9 9 U1 0 U2 2 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 NOV 5 PY 2001 VL 13 IS 44 BP L899 EP L904 DI 10.1088/0953-8984/13/44/103 PG 6 WC Physics, Condensed Matter SC Physics GA 494TG UT WOS:000172301500003 ER PT J AU McGuire, S Catterall, S Bowick, M Warner, S AF McGuire, S Catterall, S Bowick, M Warner, S TI The Ising model on a dynamically triangulated disk with a boundary magnetic field SO NUCLEAR PHYSICS B LA English DT Article ID QUANTUM-GRAVITY; 2D GRAVITY AB We use Monte Carlo simulations to study a dynamically triangulated disk with Ising spins on the vertices and a boundary magnetic field. For the case of zero magnetic field we show that the model possesses three phases. For one of these the boundary length grows linearly with disk area, while the other two phases are characterized by a boundary whose size is on the order of the cut-off. A line of continuous magnetic transitions separates the two small boundary phases. We determine the critical exponents of the continuous magnetic phase transition and relate them to predictions from continuum 2-d quantum gravity. This line of continuous transitions appears to terminate on a line of discontinuous phase transitions dividing the small boundary phases from the large boundary phase. We examine the scaling of bulk magnetization and boundary magnetization as a function of boundary magnetic field in the vicinity of this tricritical point. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Syracuse Univ, Dept Phys, Syracuse, NY 13244 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Catterall, S (reprint author), Syracuse Univ, Dept Phys, Syracuse, NY 13244 USA. RI Warner, Simeon/E-2423-2011; OI Warner, Simeon/0000-0002-7970-7855; Catterall, Simon/0000-0003-2735-2682 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 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD NOV 5 PY 2001 VL 614 IS 3 BP 467 EP 493 DI 10.1016/S0550-3213(01)00405-9 PG 27 WC Physics, Particles & Fields SC Physics GA 488CC UT WOS:000171916500003 ER PT J AU Alkofer, R Hecht, MB Roberts, CD Schmidt, SM Vinnik, DV AF Alkofer, R Hecht, MB Roberts, CD Schmidt, SM Vinnik, DV TI Pair creation and an x-ray free electron laser SO PHYSICAL REVIEW LETTERS LA English DT Article ID FIELD AB Using a quantum kinetic equation we study the possibility that focused beams at proposed x-ray free electron laser facilities can initiate spontaneous electron-positron pair production from the QED vacuum. Under conditions reckoned achievable at planned facilities, repeated cycles of particle creation and annihilation will take place in tune with the laser frequency. The peak particle number density is insensitive to this frequency, and one can anticipate the production of a few hundred particle pairs per laser period. C1 Univ Tubingen, Inst Theoret Phys, D-72076 Tubingen, Germany. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Alkofer, R (reprint author), Univ Tubingen, Inst Theoret Phys, Morgenstelle 14, D-72076 Tubingen, Germany. NR 24 TC 138 Z9 143 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 5 PY 2001 VL 87 IS 19 AR 193902 DI 10.1103/PhysRevLett.87.193902 PG 4 WC Physics, Multidisciplinary SC Physics GA 490AT UT WOS:000172027200012 PM 11690410 ER PT J AU Aronson, MC Osborn, R Chau, R Maple, MB Rainford, BD Murani, AP AF Aronson, MC Osborn, R Chau, R Maple, MB Rainford, BD Murani, AP TI Magnetic correlations and the quantum critical point of UCu5-Pd-x(x) (x = 1, 1.5) SO PHYSICAL REVIEW LETTERS LA English DT Article AB We have used inelastic neutron scattering to determine the magnetic susceptibility chi (q, omega, T) of the non-Fermi-liquid compounds UCu5-xPdx(x = 1, 1.5) for energies omega between 0.2 and 2 meV, and for temperatures T between 1.6 and 250 K. Spatial correlations in both UCu4Pd and UCu3.5Pd1.5 extend over length scales comparable to the unit cell, and display very little temperature dependence. In contrast, the wave vector independent susceptibility diverges as T --> 0. We find that the excitations at all q, and for all T and omega accessed display the same type of non-Fermi-liquid omega /T scaling. C1 Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Southampton, Dept Phys, Southampton SO17 1BJ, Hants, England. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. RP Aronson, MC (reprint author), Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. RI Osborn, Raymond/E-8676-2011 OI Osborn, Raymond/0000-0001-9565-3140 NR 0 TC 26 Z9 26 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 NOV 5 PY 2001 VL 87 IS 19 AR 197205 DI 10.1103/PhysRevLett.87.197205 PG 4 WC Physics, Multidisciplinary SC Physics GA 490AT UT WOS:000172027200057 PM 11690455 ER PT J AU Dullin, HR Gottwald, GA Holm, DD AF Dullin, HR Gottwald, GA Holm, DD TI An integrable shallow water equation with linear and nonlinear dispersion SO PHYSICAL REVIEW LETTERS LA English DT Article ID BILLIARD SOLUTIONS; PEAKED SOLITONS; PDES AB We use asymptotic analysis and a near-identity normal form transformation from water wave theory to derive a 1 + 1 unidirectional nonlinear wave equation that combines the linear dispersion of the Korteweg-deVries (KdV) equation with the nonlinear/nonlocal dispersion of the Camassa-Holtn (CH) equation. This equation is one order more accurate in asymptotic approximation beyond KdV, yet it still preserves complete integrability via the inverse scattering transform method. Its traveling wave solutions contain both the KdV solitons and the CH peakons as limiting cases. C1 Univ Loughborough, Dept Math Sci, Loughborough, Leics, England. Univ Surrey, Dept Math & Stat, Surrey, England. Los Alamos Natl Lab, CNLS, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Dullin, HR (reprint author), Univ Loughborough, Dept Math Sci, Loughborough, Leics, England. EM h.r.dullin@lboro.ac.uk; g.gottwald@eim.surrey.ac.uk; dholm@lanl.gov RI Dullin, Holger/B-2808-2008; Gottwald, Georg/K-7157-2012 OI Dullin, Holger/0000-0001-6617-196X; NR 26 TC 168 Z9 176 U1 2 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 NOV 5 PY 2001 VL 87 IS 19 AR 194501 DI 10.1103/PhysRevLett.87.194501 PG 4 WC Physics, Multidisciplinary SC Physics GA 490AT UT WOS:000172027200016 PM 11690414 ER PT J AU Krasnitz, A Nara, Y Venugopalan, R AF Krasnitz, A Nara, Y Venugopalan, R TI Coherent gluon production in very-high-energy heavy-ion collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID ULTRARELATIVISTIC NUCLEAR COLLISIONS; WILSON RENORMALIZATION-GROUP; DEEP-INELASTIC SCATTERING; CHEMICAL EQUILIBRATION; TRANSVERSE-MOMENTUM; MINIJET PRODUCTION; SMALL-X; RADIATION; DENSITY; SATURATION AB The early stages of a relativistic heavy-ion collision are examined in the framework of an effective classical SU(3) Yang-Mills theory in the transverse plane. We compute the initial energy and number distributions, per unit rapidity, at midrapidity, of gluons produced in high-energy heavy-ion collisions. We discuss the phenomenological implications of our results in light of the recent Relativistic Heavy-Ion Collider data. C1 Univ Algarve, CENTRA, P-8000 Faro, Portugal. Univ Algarve, Fac Ciencias & Tecnol, P-8000 Faro, Portugal. Brookhaven Natl Lab, RIKEN, BNL Res Ctr, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Krasnitz, A (reprint author), Univ Algarve, CENTRA, Campus Gambelas, P-8000 Faro, Portugal. NR 61 TC 192 Z9 192 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 NOV 5 PY 2001 VL 87 IS 19 AR 192302 DI 10.1103/PhysRevLett.87.192302 PG 4 WC Physics, Multidisciplinary SC Physics GA 490AT UT WOS:000172027200006 PM 11690405 ER PT J AU Nattermann, T Pokrovsky, V Vinokur, VM AF Nattermann, T Pokrovsky, V Vinokur, VM TI Hysteretic dynamics of domain walls at finite temperatures SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHARGE-DENSITY WAVES; FIELD ISING-MODEL; DEPINNING TRANSITION; DRIVEN INTERFACES; RANDOM-MEDIA; FLUX CREEP; SUPERCONDUCTORS; FLUCTUATIONS; DIMENSIONS; IMPURITIES AB Theory of domain wall motion in a random medium is extended to the case when the driving field is below the zero-temperature depinning threshold and the creep of the domain wall is induced by thermal fluctuations. Subject to an ac drive, the domain wall starts to move when the driving force exceeds an effective threshold which is temperature and frequency dependent. Similar to the case of zero temperature, the hysteresis loop displays three dynamical phase transitions at increasing ac field amplitude h(0). The phase diagram in the 3D phase space of temperature, driving force amplitude, and frequency is investigated. C1 Univ Cologne, Inst Theoret Phys, D-50937 Cologne, Germany. Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. LD Landau Theoret Phys Inst, Chernogolovka 142432, Moscow District, Russia. Argonne Natl Lab, Argonne, IL 60439 USA. RP Nattermann, T (reprint author), Univ Cologne, Inst Theoret Phys, D-50937 Cologne, Germany. NR 26 TC 87 Z9 87 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 NOV 5 PY 2001 VL 87 IS 19 AR 197005 DI 10.1103/PhysRevLett.87.197005 PG 4 WC Physics, Multidisciplinary SC Physics GA 490AT UT WOS:000172027200050 PM 11690448 ER PT J AU Naumovic, D Aebi, P Schlapbach, L Beeli, C Kunze, K Lograsso, TA Delaney, DW AF Naumovic, D Aebi, P Schlapbach, L Beeli, C Kunze, K Lograsso, TA Delaney, DW TI Formation of a stable decagonal quasicrystalline Al-Pd-Mn surface layer SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUASI-CRYSTAL AL70PD20MN10; PHOTOEMISSION SPECTROSCOPY; ELECTRONIC-STRUCTURE; ICOSAHEDRAL ALLOYS; DIFFRACTION; ORDER; HOLOGRAPHY; SYMMETRY; SYSTEM; RANGE AB We report the in situ formation of an ordered equilibrium decagonal Al-Pd-Mn quasicrystal overlayer on the fivefold symmetric surface of an icosahedral Al-Pd-Mn monograin. The decagonal structure of the epilayer is evidenced by x-ray photoelectron diffraction, low-energy electron diffraction, and electron backscatter diffraction. This overlayer is also characterized by a reduced density of states near the Fermi edge as expected for quasicrystals. This is the first time that a millimeter-size surface of the stable decagonal Al-Pd-Mn is obtained, studied, and compared to its icosahedral counterpart. C1 Univ Fribourg, Inst Phys, CH-1700 Fribourg, Switzerland. ETH Zurich, Solid State Phys Lab, CH-8093 Zurich, Switzerland. ETH Zurich, Inst Geol, CH-8092 Zurich, Switzerland. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Naumovic, D (reprint author), Univ Fribourg, Inst Phys, CH-1700 Fribourg, Switzerland. RI Kunze, Karsten/B-8561-2013 OI Kunze, Karsten/0000-0003-4682-8017 NR 40 TC 26 Z9 26 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD NOV 5 PY 2001 VL 87 IS 19 AR 195506 DI 10.1103/PhysRevLett.87.195506 PG 4 WC Physics, Multidisciplinary SC Physics GA 490AT UT WOS:000172027200026 PM 11690424 ER PT J AU Schafer, J Rotenberg, E Kevan, SD Blaha, P Claessen, R Thorne, RE AF Schafer, J Rotenberg, E Kevan, SD Blaha, P Claessen, R Thorne, RE TI High-temperature symmetry breaking in the electronic band structure of the quasi-one-dimensional solid NbSe3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHARGE-DENSITY WAVES; X-RAY; TRANSITION; METAL; GAP AB The electronic band structure of the Peierls compound NbSe3 has been explored for its symmetries with microspot synchrotron photoemission. The Fermi level crossings and deviations from one-dimensional behavior are identified. Density-functional calculations of the Fermi surfaces confirm the nesting conditions relevant for the two phase transitions. The instability along the chains with superstructure periodicity q = 0.44 Angstrom (-1) induces a backfolding of the electronic bands, and the Fermi level crossings appear suppressed. This broken symmetry is observed in the fluctuation regime at more than twice the critical temperature, where the correlation length is strongly reduced. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Augsburg, Inst Expt Phys, D-86135 Augsburg, Germany. Univ Oregon, Dept Phys, Eugene, OR 97403 USA. Tech Univ Vienna, Inst Phys & Theoret Chem, A-1060 Vienna, Austria. Cornell Univ, Atom & Solid State Phys Lab, Ithaca, NY 14853 USA. RP Schafer, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. RI Blaha, Peter/F-2847-2010; Rotenberg, Eli/B-3700-2009; Kevan, Stephen/F-6415-2010; Claessen, Ralph/A-2045-2017 OI Rotenberg, Eli/0000-0002-3979-8844; Kevan, Stephen/0000-0002-4621-9142; Claessen, Ralph/0000-0003-3682-6325 NR 21 TC 44 Z9 44 U1 2 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 NOV 5 PY 2001 VL 87 IS 19 AR 196403 DI 10.1103/PhysRevLett.87.196403 PG 4 WC Physics, Multidisciplinary SC Physics GA 490AT UT WOS:000172027200040 PM 11690438 ER PT J AU Tippens, WB Prakhov, S Allgower, CE Bekrenev, V Berger, E Briscoe, WJ Clajus, M Comfort, JR Craig, K Efendiev, A Grosnick, D Holstein, BR Huber, GM Isenhower, D Knecht, N Koetke, D Koulbardis, A Kozlenko, N Kruglov, S Lolos, GJ Lopatin, I Manley, DM Marusic, A Manweiler, R McDonald, S Nefkens, BMK Olmsted, J Papandreou, Z Phaisangittisakul, N Price, JW Pulver, M Ramirez, AF Sadler, ME Shafi, A Spinka, H Stanislaus, S Starostin, A Staudenmaier, HM AF Tippens, WB Prakhov, S Allgower, CE Bekrenev, V Berger, E Briscoe, WJ Clajus, M Comfort, JR Craig, K Efendiev, A Grosnick, D Holstein, BR Huber, GM Isenhower, D Knecht, N Koetke, D Koulbardis, A Kozlenko, N Kruglov, S Lolos, GJ Lopatin, I Manley, DM Marusic, A Manweiler, R McDonald, S Nefkens, BMK Olmsted, J Papandreou, Z Phaisangittisakul, N Price, JW Pulver, M Ramirez, AF Sadler, ME Shafi, A Spinka, H Stanislaus, S Starostin, A Staudenmaier, HM CA Crystal Ball Collaboration TI Determination of the quadratic slope parameter in eta -> 3 pi(0) decay SO PHYSICAL REVIEW LETTERS LA English DT Article ID DALITZ-PLOT; ETA->3-PI; PHYSICS; MESON; ETA AB We have determined the quadratic slope parameter alpha for eta -->3 pi (0) to be alpha = -0.031(4) from a 99% pure sample of 10(6)eta -->3 pi (0) decays produced in the reaction pi (-) p -->n mu close to the eta threshold using the Crystal Ball detector at the AGS. The result is four times more precise than the present world data and disagrees with current chiral perturbation theory calculations by about four standard deviations. C1 Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Abilene Christian Univ, Abilene, TX 79699 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Arizona State Univ, Tempe, AZ 85287 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. George Washington Univ, Washington, DC 20052 USA. Univ Karlsruhe, D-76128 Karlsruhe, Germany. Kent State Univ, Kent, OH 44242 USA. Univ Massachusetts, Amherst, MA 01003 USA. Petersburg Nucl Phys Inst, Gatchina 188350, Leningrad Dist, Russia. Univ Regina, Regina, SK S4S 0A2, Canada. Valparaiso Univ, Valparaiso, IN 46383 USA. RP Tippens, WB (reprint author), Univ Calif Los Angeles, Los Angeles, CA 90095 USA. NR 15 TC 64 Z9 64 U1 0 U2 2 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 NOV 5 PY 2001 VL 87 IS 19 AR 192001 DI 10.1103/PhysRevLett.87.192001 PG 4 WC Physics, Multidisciplinary SC Physics GA 490AT UT WOS:000172027200004 PM 11690403 ER PT J AU Zhu, JX Kim, W Ting, CS Carbotte, JP AF Zhu, JX Kim, W Ting, CS Carbotte, JP TI Quasiparticle states around a nonmagnetic impurity in a d-density-wave state of high-T-c cuprates SO PHYSICAL REVIEW LETTERS LA English DT Article ID SUPERCONDUCTING GAP; BI2SR2CACU2O8+DELTA; PSEUDOGAP; SURFACE; MODEL; PROBE AB The electronic structure around a single nonmagnetic impurity in the d-density-wave (DDW) ordering is studied. It is found that a single subgap resonance peak appears in the local density of states around the impurity In the unitary limit, the position of this resonance peak shifts away from the Fermi energy in accord with the chemical potential. This result is dramatically different from the case of the pure superconducting state for which the impurity resonant energy is approximately pinned at the Fermi level. This can be used to probe the existence of the DDW ordering in cuprates. C1 Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. RP Zhu, JX (reprint author), Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. NR 31 TC 53 Z9 54 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 NOV 5 PY 2001 VL 87 IS 19 AR 197001 DI 10.1103/PhysRevLett.87.197001 PG 4 WC Physics, Multidisciplinary SC Physics GA 490AT UT WOS:000172027200046 PM 11690444 ER PT J AU Kriesel, JW Tilley, TD AF Kriesel, JW Tilley, TD TI Carbosilane dendrimers as nanoscopic building blocks for hybrid organic-inorganic materials and catalyst supports SO ADVANCED MATERIALS LA English DT Article ID XEROGELS AB Advanced nanoarchitectures can be achieved by covalent linking of dendrimeric modules into porous networks using sol-gel chemistry. The focus of this work lies in the conversion of second, third, and fourth generation carbosilane dendrimers to high surface area xerogels and aerogels, and the use of these materials as catalyst supports. By varying the hydrolysis solvent and dendrimeric precursor employed, the properties of the nanoarchitectures can be easily tuned. In particular, triethoxysilyl-terminated dendrimers have been hydrolyzed in solvents of varying polarity with acid catalysts to produce micro- and mesoporous hybrid dendrimer xerogels and aerogels with a controllable degree of Si-OH functionality. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Tilley, TD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 20 TC 38 Z9 39 U1 0 U2 7 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0935-9648 J9 ADV MATER JI Adv. Mater. PD NOV 2 PY 2001 VL 13 IS 21 BP 1645 EP 1648 DI 10.1002/1521-4095(200111)13:21<1645::AID-ADMA1645>3.3.CO;2-T PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 492QG UT WOS:000172178600014 ER PT J AU Gertsman, VY AF Gertsman, VY TI Coincidence site lattice theory of multicrystalline ensembles SO ACTA CRYSTALLOGRAPHICA SECTION A LA English DT Article ID TRIPLE JUNCTIONS; POLYCRYSTALS; DISTRIBUTIONS AB It is shown how the coincidence site lattice theory, developed originally for grain boundaries and extended recently to triple junctions, can be applied to more complex ensembles of crystallites with the cubic crystal structure. These include quadruple points, multiple junctions of grains and other multicrystal assemblies. Application of the theory is demonstrated on hypothetical examples, which may help elucidate some practically important problems. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gertsman, VY (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 11 TC 22 Z9 22 U1 0 U2 7 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7673 J9 ACTA CRYSTALLOGR A JI Acta Crystallogr. Sect. A PD NOV PY 2001 VL 57 BP 649 EP 655 DI 10.1107/S0108767301009102 PN 6 PG 7 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 485RZ UT WOS:000171777300003 PM 11679694 ER PT J AU Somoza, JR Szoke, A Szoke, H AF Somoza, JR Szoke, A Szoke, H TI A simple inverse method for calculating electron-density maps SO ACTA CRYSTALLOGRAPHICA SECTION A LA English DT Article ID X-RAY CRYSTALLOGRAPHY; HOLOGRAPHIC METHODS; CRYSTAL-STRUCTURE AB Electron-density maps are generally prepared by Fourier transforming a set of complex structure factors. However, a map can also be obtained through a real-space reconstruction method. Starting from an empty unit cell, the map can be iteratively modified until it agrees with the given structure factors. In this paper, a simple method is described for preparing electron-density maps using this technique and two examples of its application are given. C1 Axys Pharmaceut Inc, S San Francisco, CA 94080 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Somoza, JR (reprint author), Axys Pharmaceut Inc, 385 Oyster Point Blvd,Suite 1, S San Francisco, CA 94080 USA. NR 11 TC 4 Z9 4 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7673 J9 ACTA CRYSTALLOGR A JI Acta Crystallogr. Sect. A PD NOV PY 2001 VL 57 BP 678 EP 680 DI 10.1107/S0108767301010650 PN 6 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 485RZ UT WOS:000171777300006 PM 11679697 ER PT J AU Bryan, JC Engle, NL Sachleben, RA Hay, BP AF Bryan, JC Engle, NL Sachleben, RA Hay, BP TI Tribenzo-18-crown-6 acetonitrile disolvate SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID CROWN-ETHERS; ION SELECTIVITY; EXTRACTION; LIGANDS AB Tribenzo-18-crown-6 binds two acetonitrile ligands, i.e. C24H24O6. 2C(2)H(3)N, one to each face of the crown ring. The crown conformation is relatively low in energy, but does not appear optimized for cation binding. Few significant intermolecular interactions are observed. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bryan, JC (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 15 TC 1 Z9 1 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD NOV PY 2001 VL 57 BP 1359 EP 1360 DI 10.1107/S0108270101016109 PN 11 PG 2 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 491HE UT WOS:000172102300045 PM 11706275 ER PT J AU Retailleau, P Yin, YH Hu, M Roach, J Bricogne, G Vonrhein, C Roversi, P Blanc, E Sweet, RM Carter, CW AF Retailleau, P Yin, YH Hu, M Roach, J Bricogne, G Vonrhein, C Roversi, P Blanc, E Sweet, RM Carter, CW TI High-resolution experimental phases for tryptophanyl-tRNA synthetase (TrpRS) complexed with tryptophanyl-5 ' AMP SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID TRANSFER-RNA-SYNTHETASE; ANGSTROM CRYSTAL-STRUCTURE; PROTEIN STRUCTURES; EVOLUTIONARY RELATIONSHIPS; QUANTITATIVE-ANALYSIS; ANOMALOUS SCATTERING; DIFFRACTION DATA; SITE; CRYSTALLOGRAPHY; REFINEMENT AB Native data, anomalous data at three wavelengths and an independent peak-wavelength data set for SeMet-substituted protein have been collected from cryoprotected crystals of the TrpRS-adenylate product (TAM) complex to a resolution limit of 1.7 Angstrom. Independent phase sets were developed using SHARP and improved by solvent flipping with SOLOMON using molecular envelopes derived from experimental densities for, respectively, peak-wavelength SAD data from four different crystals, MAD data and their M(S)IRAS combinations with native data. Hendrickson-Lattman phase-probability coefficients from each phase set were used in BUSTER to drive maximum-likelihood refinements of well defined parts of the previously refined room-temperature 2.9 Angstrom structure. Maximum-entropy completion followed by manual rebuilding was then used to generate a model for the missing segments, bound ligand and solvent molecules. Surprisingly, peak-wavelength SAD experiments produced the smallest phase errors relative to the refined structures. Selenomethionylated models deviate from one another by 0.25 Angstrom and from the native model by 0.38 Angstrom, but all have r.m.s. deviations of similar to1.0 Angstrom from the 2.9 Angstrom model. Difference Fourier calculations between amplitudes from the 300 K experiment and the new amplitudes at 100 K using 1.7 Angstrom model phases show no significant structural changes arising from temperature variation or addition of cryoprotectant. The main differences between low- and high-resolution structures arise from correcting side-chain rotamers in the core of the protein as well as on the surface. These changes improve various structure-validation criteria. C1 Univ N Carolina, Dept Biochem & Biophys, Chapel Hill, NC 27514 USA. MRC, Mol Biol Lab, Cambridge CB2 2QH, England. LURE, F-91405 Orsay, France. Brookhaven Natl Lab, Dept Biol, Upton, NY 11937 USA. RP Carter, CW (reprint author), Univ N Carolina, Dept Biochem & Biophys, CB 7260, Chapel Hill, NC 27514 USA. RI Blanc, Eric/C-5424-2009; Roversi, Pietro/F-8925-2011 OI Roversi, Pietro/0000-0001-9280-9437 FU NCRR NIH HHS [1P41 RR12408-01A1]; NIGMS NIH HHS [GM48519] NR 63 TC 25 Z9 25 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD NOV PY 2001 VL 57 BP 1595 EP 1608 DI 10.1107/S090744490101215X PN 11 PG 14 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 485TA UT WOS:000171778400014 PM 11679724 ER PT J AU Perbandt, M Chandra, V Rajashankar, KR Idakieva, K Parvanova, K Rypniewski, W Stoeva, S Voelter, W Genov, N Betzel, C AF Perbandt, M Chandra, V Rajashankar, KR Idakieva, K Parvanova, K Rypniewski, W Stoeva, S Voelter, W Genov, N Betzel, C TI Preliminary X-ray diffraction studies of the external functional unit RtH2-e from the Rapana thomasiana SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID FROZEN-HYDRATED SPECIMENS; 3-DIMENSIONAL RECONSTRUCTION; HEMOCYANIN SUBUNIT; CRYSTAL-STRUCTURE; ORGANIZATION; DISSOCIATION; RESOLUTION; SEQUENCE AB The 'external' oxygenated functional unit RtH2-e of the Rapana hemocyanin subunit RHSS2 was isolated and crystallized. X-ray intensity data to 3.3 Angstrom resolution have been collected at 100 K and the structure has been solved using the molecular-replacement method. The space group is assigned to be the tetragonal P4(3) 2(1)2, with unit-cell parameters a = b = 105.5, c = 375.0 Angstrom. C1 DESY, Univ Hosp Hamburg, Inst Med Biochem & Mol Biol, D-22603 Hamburg, Germany. All India Inst Med Sci, Dept Biophys, New Delhi 110029, India. Brookhaven Natl Lab, Upton, NY 11973 USA. Rockefeller Univ, Upton, NY 11973 USA. Bulgarian Acad Sci, Inst Organ Chem, BU-1113 Sofia, Bulgaria. Univ Tubingen, Inst Physiol Chem, Dept Phys Biochem, D-72076 Tubingen, Germany. RP Betzel, C (reprint author), DESY, Univ Hosp Hamburg, Inst Med Biochem & Mol Biol, Bldg 22A,Notkestr 85, D-22603 Hamburg, Germany. OI Idakieva, Krassimira/0000-0002-5523-7043 NR 25 TC 1 Z9 2 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD NOV PY 2001 VL 57 BP 1663 EP 1665 DI 10.1107/S0907444901012124 PN 11 PG 3 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 485TA UT WOS:000171778400027 PM 11679737 ER PT J AU Eswaramoorthy, S Kumaran, D Swaminathan, S AF Eswaramoorthy, S Kumaran, D Swaminathan, S TI Crystallographic evidence for doxorubicin binding to the receptor-binding site in Clostridium botulinum neurotoxin B SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID BACTERIAL PROTEIN TOXINS; TETANUS TOXIN; NEUROEXOCYTOSIS; IDENTIFICATION; GANGLIOSIDE; SOFTWARE; PROGRAM AB The neurotoxins of Clostridium botulinum and tetanus bind to gangliosides as a first step of their toxin activity. Identifying suitable receptors that compete with gangliosides could prevent toxin binding to the neuronal cells. A possible ganglioside-binding site of the botulinum neurotoxin B (BoNT/B) has already been proposed and evidence is now presented for a drug binding to botulinum neurotoxin B from structural studies. Doxorubicin, a well known DNA intercalator, binds to the neurotoxin at the receptor-binding site proposed earlier. The structure of the BoNT/B-doxorubicin complex reveals that doxorubicin has interactions with the neurotoxin similar to those of sialyllactose. The aglycone moiety of the doxorubicin stacks with tryptophan 1261 and interacts with histidine 1240 of the binding domain. Here, the possibility is presented of designing a potential antagonist for these neurotoxins from crystallographic analysis of the neurotoxin-doxorubicin complex, which will be an excellent lead compound. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Swaminathan, S (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 25 TC 28 Z9 30 U1 1 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD NOV PY 2001 VL 57 BP 1743 EP 1746 DI 10.1107/S0907444901013531 PN 11 PG 4 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 485TA UT WOS:000171778400053 PM 11679763 ER PT J AU Osipiuk, J Gornicki, P Maj, L Dementieva, I Laskowski, R Joachimiak, A AF Osipiuk, J Gornicki, P Maj, L Dementieva, I Laskowski, R Joachimiak, A TI Streptococcus pneumonia YlxR at 1.35 angstrom shows a putative new fold SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID 16S RIBOSOMAL-RNA; ESCHERICHIA-COLI; CRYSTAL-STRUCTURE; MESSENGER-RNA; PROTEIN; REFINEMENT; NUSA; SYSTEM; TARGET; MODEL AB The structure of the YlxR protein of unknown function from Streptococcus pneumonia was determined to 1.35 Angstrom. YlxR is expressed from the nusA/infB operon in bacteria and belongs to a small protein family (COG2740) that shares a conserved sequence motif GRGA(Y/W). The family shows no significant amino-acid sequence similarity with other proteins. Three-wavelength diffraction MAD data were collected to 1.7 Angstrom from orthorhombic crystals using synchrotron radiation and the structure was determined using a semiautomated approach. The YlxR structure resembles a two-layer alpha/beta sandwich with the overall shape of a cylinder and shows no structural homology to proteins of known structure. Structural analysis revealed that the YlxR structure represents a new protein fold that belongs to the alpha-beta plait superfamily. The distribution of the electrostatic surface potential shows a large positively charged patch on one side of the protein, a feature often found in nucleic acid-binding proteins. Three sulfate ions bind to this positively charged surface. Analysis of potential binding sites uncovered several substantial clefts, with the largest spanning 3/4 of the protein. A similar distribution of binding sites and a large sharply bent cleft are observed in RNA-binding proteins that are unrelated in sequence and structure. It is proposed that YlxR is an RNA-binding protein. C1 Argonne Natl Lab, Struct Biol Ctr, Argonne, IL 60439 USA. Univ Chicago, Dept Mol Genet & Cell Biol, Chicago, IL 60637 USA. Univ London Birkbeck Coll, Dept Crystallog, London WC1E 7HX, England. RP Joachimiak, A (reprint author), Argonne Natl Lab, Struct Biol Ctr, 9700 S Cass Ave, Argonne, IL 60439 USA. FU NIGMS NIH HHS [GM62414-01, P50 GM062414, P50 GM062414-01] NR 31 TC 12 Z9 12 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD NOV PY 2001 VL 57 BP 1747 EP 1751 DI 10.1107/S0907444901014019 PN 11 PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 485TA UT WOS:000171778400054 PM 11679764 ER PT J AU Bellamy, HD Snell, EH Lovelace, J Pokross, M Borgstahl, GEO AF Bellamy, HD Snell, EH Lovelace, J Pokross, M Borgstahl, GEO TI The high-mosaicity illusion: revealing the true physical characteristics of macromolecular crystals (vol D56, pg 986, 2000) SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Correction C1 Univ Toledo, Dept Chem, Toledo, OH 43606 USA. NASA, George C Marshall Space Flight Ctr, Struct Biol Lab, Huntsville, AL 35812 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Borgstahl, GEO (reprint author), Univ Toledo, Dept Chem, 2801 W Bancroft St, Toledo, OH 43606 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD NOV PY 2001 VL 57 BP 1754 EP 1754 DI 10.1107/S0907444901017115 PN 11 PG 1 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 485TA UT WOS:000171778400056 ER PT J AU Indacochea, JE McDeavitt, S Billings, GW AF Indacochea, JE McDeavitt, S Billings, GW TI Interface interactions of dissimilar materials at elevated temperatures SO ADVANCED ENGINEERING MATERIALS LA English DT Article ID SILICON-NITRIDE; METALS; WETTABILITY; SYSTEMS; ALLOYS; CU AB This paper reviews some of the chemical interactions that occurred at the interface of ceramic/molten metal liquids. Control of interfacial reactions between dissimilar materials is an important issue in numerous technological applications, such as brazing of ceramics to metals, design of ceramic-metal composites, coatings of ceramics on metal substrates, and development of crucibles for melting of refractory metals. In ceramic/metal systems, wetting of the ceramic surface by the liquid metal is typically accompanied to some extent by interfacial reactions, The chemical incompatibility between the metal and non-metallic materials can result in the formation of undesirable phases, due to the chemical and metallurgical reactions that take place during processing or in service. There is a need, therefore, to characterize the governing factors and reaction pathways at these interfaces. So, when the reaction products obtained during interdiffusion processing are not favorable, the diffusion pathway can be modified to control their formation. C1 Univ Illinois, CME Dept MC246, Chicago, IL 60607 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. W CERAC Inc, McCarran, NV 89439 USA. RP Indacochea, JE (reprint author), Univ Illinois, CME Dept MC246, 842 W Taylor St, Chicago, IL 60607 USA. NR 19 TC 7 Z9 7 U1 1 U2 5 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 1438-1656 J9 ADV ENG MATER JI Adv. Eng. Mater. PD NOV PY 2001 VL 3 IS 11 BP 895 EP 901 DI 10.1002/1527-2648(200111)3:11<895::AID-ADEM895>3.0.CO;2-L PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 497TV UT WOS:000172472300014 ER PT J AU Reidys, CM AF Reidys, CM TI On acyclic orientations and sequential dynamical systems SO ADVANCES IN APPLIED MATHEMATICS LA English DT Article DE acyclic orientations; sequential dynamical system; orderings; graph automorphisms AB We study a class of discrete dynamical systems that consists of the following data: (a) a finite (labeled) graph Y with vertex set {1,...,n}, where cacti vertex has a binary state, (b) a vertex labeled multi-set of functions (F-i,F-Y: F-2(n) --> F-2(n))(i), and (c) a permutation pi epsilon S-n. The function F-i,F-Y updates the binary state of vertex i as a function of the states of vertex i and its Y-neighbors and leaves the states of all other vertices fixed. The permutation pi represents a Y-vertex ordering according to which the functions F-i,F-Y are applied. By composing the functions F-i,F-Y in the order given by pi we obtain the sequential dynamical system (SDS): [F-Y, pi] = F-pi(n),F-Y o...o F-pi(1): F-2(n) - F-2(n). In this paper we first establish a sharp, combinatorial upper bound on the number of non-equivalent SI)Ss for fixed graph Y and multi-set of functions (F-i,F-Y). Second, we analyze the structure of a certain class of fixed-point-free SDSs. (C) 2001 Elsevier Science. Science. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Reidys, CM (reprint author), Los Alamos Natl Lab, D 2, Los Alamos, NM 87545 USA. NR 5 TC 15 Z9 15 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0196-8858 J9 ADV APPL MATH JI Adv. Appl. Math. PD NOV PY 2001 VL 27 IS 4 BP 790 EP 804 DI 10.1006/aama.2001.0761 PG 15 WC Mathematics, Applied SC Mathematics GA 508MG UT WOS:000173092400005 ER PT J AU Quinn, NWT Miller, NL Dracup, JA Brekke, L Grober, LF AF Quinn, NWT Miller, NL Dracup, JA Brekke, L Grober, LF TI An integrated modeling system for environmental impact analysis of climate variability and extreme weather events in the San Joaquin Basin, California SO ADVANCES IN ENVIRONMENTAL RESEARCH LA English DT Article; Proceedings Paper CT International Symposium on Environmental Software Systems (ISESS 2000) CY MAY, 2000 CL ZELL, AUSTRIA DE water resources; decision support system; impacts analysis; hydroclimate; climate change; CALFED ID RIVER FLOW; PRECIPITATION; BUDGET AB This collaborative research project has two main objectives: to assess the vulnerability of water supply, water demand, water quality, ecosystem health and socioeconomic welfare within the San Joaquin River Basin as a function of climate variability and extreme weather events; and to provide guidance in the formulation of effective management strategies to mitigate the range of potential impacts due to climate variability and extreme weather. The project involves updating and advancing previous studies on climate change in California. Climate data are based on new Global Circulation Model output from the statistical downscaling that converts GCM climate forecasts into local weather forecasts. The project applies these climate data to perturb an existing 72-year historical hydrologic time series of the San Joaquin Basin to develop an integrated impacts analysis of climate change/variability on the water, economic and social resources of the Basin. Previous studies focused only on water resource impacts. A decision support system (DSS) is under development that will provide assistance to CALFED (a joint California State and Federal program designed to resolve water issues in the Bay-Delta) in water resource and ecosystem management of the San Joaquin Basin. (C) 2001 Elsevier Science Ltd. AR rights reserved. C1 Univ Calif Berkeley, Inst Environm Sci & Engn, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. Cent Valley Reg Water Qual Control Board, Sacramento, CA 95827 USA. RP Quinn, NWT (reprint author), Univ Calif Berkeley, Inst Environm Sci & Engn, Lawrence Berkeley Lab, 412 OBrien Hall,Bld 70A-3317F,1 Cyclotron Rd, Berkeley, CA 94720 USA. OI Quinn, Nigel/0000-0003-3333-4763 NR 18 TC 6 Z9 6 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1093-0191 J9 ADV ENVIRON RES JI Adv. Environ. Res. PD NOV PY 2001 VL 5 IS 4 BP 309 EP 317 DI 10.1016/S1093-0191(01)00081-8 PG 9 WC Engineering, Environmental; Engineering, Chemical SC Engineering GA 482VF UT WOS:000171597400002 ER PT J AU Nakaso, K Fujimoto, T Seto, T Shimada, M Okuyama, K Lunden, MM AF Nakaso, K Fujimoto, T Seto, T Shimada, M Okuyama, K Lunden, MM TI Size distribution change of titania nano-particle agglomerates generated by gas phase reaction, agglomeration, and sintering SO AEROSOL SCIENCE AND TECHNOLOGY LA English DT Article ID CHEMICAL VAPOR-DEPOSITION; TIO2 PARTICLES; AEROSOL; COAGULATION; COALESCENCE; OXIDATION; EVOLUTION; KINETICS; EQUATION; POWDER AB In the manufacturing of nanometer-sized material particlulates by aerosol gas-to-particle conversion processes, it is important to analyze how the gas-phase chemical reaction, nucleation, agglomeration, and sintering rates control the size distribution and morphology of particles. In this study, titania particles were produced experimentally by the thermal decomposition of titanium tetraisopropoxide (TTIP) and oxidation of titanium tetrachloride (TiCl4) using a laminar ? ow aerosol reactor. The effect of reaction temperature on the size and morphology of the generated particles was investigated under various conditions. The size distributions of agglomerates were measured using a DMA/CNC system. The size distributions of primary particles were measured using TEM pictures of the agglomerates sampled by a thermophoretic aerosol sampler. In order to model the growth of both agglomerates and primary particles simultaneously, a two-dimensional discrete-sectional representation of the size distribution was employed, solving the aerosol general dynamic equation for chemical reaction, agglomeration, and sintering. Qualitative agreement between the experimentally observed results and the simulation are satisfactory for the large variations in reactor temperature explored. C1 Hiroshima Univ, Grad Sch Chem Engn, Higashihiroshima 724, Japan. Minist Int Trade & Ind, Agcy Ind Sci & Technol, Mech Engn Lab, Tsukuba, Ibaraki 305, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Engn Technol Div, Berkeley, CA 94720 USA. RP Okuyama, K (reprint author), Hiroshima Univ, Grad Sch Engn, Dept Chem Engn, 1-4-1 Kagamiyama, Higashihiroshima 7398527, Japan. RI Shimada, Manabu/D-5367-2011; okuyama, kikuo/F-6092-2010; Seto, Takafumi/D-2874-2012; Fujimoto, Toshiyuki/N-3052-2014 NR 32 TC 41 Z9 42 U1 0 U2 18 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0278-6826 J9 AEROSOL SCI TECH JI Aerosol Sci. Technol. PD NOV PY 2001 VL 35 IS 5 BP 929 EP 947 DI 10.1080/02786820126857 PG 19 WC Engineering, Chemical; Engineering, Mechanical; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 487AM UT WOS:000171851600009 ER PT J AU Sung, H Foley, BT Bae, IG Chi, HS Cho, YK AF Sung, H Foley, BT Bae, IG Chi, HS Cho, YK TI Phylogenetic analysis of reverse transcriptase in antiretroviral drug-naive Korean HIV type 1 patients SO AIDS RESEARCH AND HUMAN RETROVIRUSES LA English DT Article ID TRANSMISSION; RESISTANCE AB To study whether genotypic antiretroviral resistance testing (GART) is needed to guide initial antiretroviral therapy in Korea, we determined partial pol sequences in peripheral blood mononuclear cells (PBMCs) obtained from 29 antiretroviral drug-naive HIV-1 patients. Phylogenetic analysis revealed four subtypes: B (23 patients), D (1 patient), recombinant strain (2 patients), and "untyped" (3 patients). Eighteen (78.3%) of the 23 subtype B isolates formed a distinct monophyletic cluster. The average genetic distances of 23 subtype B compared with reference strain HXB2 were 2.7% (range, 1.5-4.6%). Only one patient harbored variant virus containing a V179D mutation causing resistance to efavirenz. These data derived from therapy-naive patients suggest that potential use of primary resistance testing to guide initial antiretroviral therapy should be considered in Korea. This is the first report on the molecular nature of HIV-1 RT in Korea. C1 Univ Ulsan, Coll Med, Dept Microbiol, Seoul 138736, South Korea. Univ Ulsan, Coll Med, Dept Clin Pathol, Seoul 138736, South Korea. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Ulsan, Coll Med, Dept Internal Med, Seoul 138736, South Korea. RP Cho, YK (reprint author), Univ Ulsan, Coll Med, Dept Microbiol, 388-1 Pungnap Dong, Seoul 138736, South Korea. OI Foley, Brian/0000-0002-1086-0296 NR 14 TC 18 Z9 19 U1 0 U2 1 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 0889-2229 J9 AIDS RES HUM RETROV JI Aids Res. Hum. Retrovir. PD NOV PY 2001 VL 17 IS 16 BP 1549 EP 1554 DI 10.1089/08892220152644250 PG 6 WC Immunology; Infectious Diseases; Virology SC Immunology; Infectious Diseases; Virology GA 492WB UT WOS:000172189600010 PM 11709099 ER PT J AU Lowe, X Eskenazi, B Nelson, DO Kidd, S Alme, A Wyrobek, AJ AF Lowe, X Eskenazi, B Nelson, DO Kidd, S Alme, A Wyrobek, AJ TI Frequency of XY sperm increases with age in fathers of boys with Klinefelter syndrome SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Article ID IN-SITU HYBRIDIZATION; FLUORESCENCE INSITU HYBRIDIZATION; PATERNAL AGE; MULTICOLOR FISH; DOWN-SYNDROME; Y-CHROMOSOME; REDUCED RECOMBINATION; HUMAN SPERMATOZOA; GERM-CELLS; SEX-RATIOS AB With increasing availability of drugs for impotence and advanced reproductive technologies for the treatment of subfertility, more men are fathering children at advanced ages. We conducted a study of the chromosomal content of sperm of healthy men aged 24-57 years to (a) determine whether father's age was associated with increasing frequencies of aneuploid sperm including XY, disomy X, disomy Y, disomy 21, and sperm diploidy, and (b) examine the association between the frequencies of disomy 21 and sex-chromosomal aneuploidies. The study group consisted of 38 fathers of boys with Klinefelter syndrome (47, XXY) recruited nationwide, and sperm aneuploidy was assessed using multicolor X-Y-21 sperm FISH (10,000 sperm per donor). Paternal age was significantly correlated with the sex ratio of sperm (Y/X; P=.006) and with the frequency of XY sperm (P=.02), with a clear trend with age by decades (P<.006). Compared with fathers in their 20s (who had an average frequency of 7.5 XY sperm per 10,000), the frequencies of XY sperm were 10% higher among fathers in their 30s, 31% higher among those in their 40s, and 160% higher among those in their 50s (95% CI 69%-300%). However, there was no evidence for age effects on frequencies of sperm carrying nullisomy sex; disomies X, Y, or 21; or meiosis I or II diploidies. The frequencies of disomy 21 sperm were significantly associated with sex-chromosomal aneuploidy (P=.04)-in particular, with disomy X (P=.004), but disomy 21 sperm did not preferentially carry either sex chromosome. These findings suggest that older fathers produce higher frequencies of XY sperm, which may place them at higher risk of fathering boys with Klinefelter syndrome, and that age effects on sperm aneuploidy are chromosome specific. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. RP Wyrobek, AJ (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, 7000 East Ave, Livermore, CA 94550 USA. EM wyrobek1@llnl.gov FU NIEHS NIH HHS [P4ZEES04705, P42 ES004705] NR 58 TC 57 Z9 63 U1 0 U2 1 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD NOV PY 2001 VL 69 IS 5 BP 1046 EP 1054 DI 10.1086/323763 PG 9 WC Genetics & Heredity SC Genetics & Heredity GA 479PU UT WOS:000171413400012 PM 11582569 ER PT J AU Swift, PN Force, ER AF Swift, PN Force, ER TI Subduction-margin assembilages in the proterozoic Pinal and Cochise blocks, southeastern Arizona SO AMERICAN JOURNAL OF SCIENCE LA English DT Article ID NORTH-AMERICA; DISRUPTION; MELANGES; TERRANES AB Protoliths of Paleoproterozoic rocks broadly referred to as "Pinal Schist" in the Johnny Lyon Hills and the Dragoon and Little Dragoon Mountains of Cochise County, Arizona, include intrusive and subaqueous extrusive mafic rocks, turbiditic clastic rocks, and highly deformed sedimentary rocks visually similar to Phanerozoic melanges. The combination of these lithologies and their present spatial distribution-clastic rocks to the northwest separated by a region of melange from mafic igneous rocks to the southeast-is suggestive of an assemblage formed at a subduction-type continental margin. Protoliths of the mafic rock sequence, about 700 m thick, consist upward from its base of composite diabase dikes, pillow lavas, and pillow breccias, and pelitic sedimentary rocks; it may be an ophiolite fragment. The clastic rocks, though complexly deformed, form a largely coherent, mostly northwest-younging sequence. A fault-bounded deformed belt, present between the mafic and the clastic rocks, includes pre-metamorphic melange and broken formation. The study area falls along or near previously suggested boundaries between lithotectonic assemblages within die Precambrian rocks of southeastern Arizona. Our results provide insight into the location and nature of the boundary and strongly suggest the presence of a suture zone juxtaposing predominantly metavolcanic rocks to the southeast against predominantly metasedimentary rocks to the northwest. Consistent with the terminology used by Eisele and Isachsen (this issue), we adopt the terms Cochise block and Pinal block for the regions to the southeast and northwest of the suture, respectively. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Arizona, Dept Geosci, Tucson, AZ 85721 USA. RP Swift, PN (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 36 TC 7 Z9 7 U1 0 U2 1 PU KLINE GEOLOGY LABORATORY PI NEW HAVEN PA YALE UNIV, NEW HAVEN, CT 06520-8109 USA SN 0002-9599 J9 AM J SCI JI Am. J. Sci. PD NOV PY 2001 VL 301 IS 9 BP 755 EP 772 DI 10.2475/ajs.301.9.755 PG 18 WC Geosciences, Multidisciplinary SC Geology GA 537KX UT WOS:000174758700001 ER PT J AU Fornstedt, T Guiochon, G AF Fornstedt, T Guiochon, G TI Nonlinear effects in LC and chiral LC SO ANALYTICAL CHEMISTRY LA English DT Article ID MASS-TRANSFER KINETICS; PREPARATIVE LIQUID-CHROMATOGRAPHY; SIMULATED MOVING-BED; CBH-I-SILICA; PROPRANOLOL ENANTIOMERS; ADSORPTION BEHAVIOR; CELLOBIOHYDROLASE-I; TRICHODERMA-REESEI; STATIONARY-PHASE; LINEAR CHROMATOGRAPHY C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Uppsala, Uppsala, Sweden. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 50 TC 22 Z9 22 U1 0 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD NOV 1 PY 2001 VL 73 IS 21 BP 608A EP 617A DI 10.1021/ac012533b PG 10 WC Chemistry, Analytical SC Chemistry GA 489LH UT WOS:000171992500008 PM 11721948 ER PT J AU Belov, ME Anderson, GA Angell, NH Shen, YF Tolic, N Udseth, HR Smith, RD AF Belov, ME Anderson, GA Angell, NH Shen, YF Tolic, N Udseth, HR Smith, RD TI Dynamic range expansion applied to mass spectrometry based on data-dependent selective ion ejection in capillary liquid chromatography Fourier transform ion cyclotron resonance for enhanced proteome characterization SO ANALYTICAL CHEMISTRY LA English DT Article ID STORAGE ASSISTED DISSOCIATION; ELECTROSPRAY-IONIZATION; TRAP; SPECTROSCOPY; SYSTEM AB The characterization of cellular proteomes is important for understanding biochemical processes ranging from cell differentiation to cancer development. In one highly promising approach, whole protein extracts or fractions are digested (e.g., with trypsin) and injected into a packed capillary column for subsequent separation. The separated peptides are then introduced on-line to an electrospray ionization source of a Fourier transform ion cyclotron resonance (FTICR) mass spectrometer for the detection of peptide accurate mass tags that serve as biomarkers for their parent proteins. In this work, we report the use of data-dependent selective external ion ejection in conjunction with FTICR and on-line capillary LC separations for the enhanced characterization of peptide mixtures and a yeast extract proteome. The number of peptides identified in an LC-FTICR analysis of a yeast proteome digest employing data-dependent rf-only dipolar ejection of the most abundant ion species prior to ion accumulation was 40% higher than that detected in a separate LC-FTICR analysis using conventional nonselective ion accumulation. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 FU NCI NIH HHS [CA81654] NR 35 TC 52 Z9 52 U1 0 U2 5 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 NOV 1 PY 2001 VL 73 IS 21 BP 5052 EP 5060 DI 10.1021/ac010733h PG 9 WC Chemistry, Analytical SC Chemistry GA 489LH UT WOS:000171992500018 PM 11721899 ER PT J AU Yu, C Davey, MH Svec, F Frechet, JMJ AF Yu, C Davey, MH Svec, F Frechet, JMJ TI Monolithic porous polymer for on-chip solid-phase extraction and preconcentration prepared by photoinitiated in situ polymerization within a microfluidic device SO ANALYTICAL CHEMISTRY LA English DT Article ID CAPILLARY-ELECTROPHORESIS; LIQUID-CHROMATOGRAPHY; MASS-SPECTROMETRY; SURFACE-CHEMISTRY; ORGANIC-COMPOUNDS; TRACE ENRICHMENT; SEPARATION MEDIA; CONTINUOUS BEDS; NATURAL-WATERS; ELECTROCHROMATOGRAPHY AB Monolithic porous polymers have been prepared by photoinitiated polymerization within the channels of a microfluidic device and used for on-chip solid-phase extraction and preconcentration. The preparation of the monolithic material with hydrophobic and ionizable surface chemistries is easily achieved by copolymerization of butyl methacrylate with ethylene dimethacrylate, or 2-hydroxyethyl methacrylate and [2-(methacryloyloxy)ethyl]trimethylammonium. chloride with ethylene dimethacrylate, respectively. The porous properties, and consequently the flow resistance, of the monolithic device are controlled by the use of a mixture of hexane and methanol as a porogenic mixture. This mixture was designed to meet the specific requirements for pore formation within macroporous monoliths useful in the microfluidic formats. The low flow resistance enables high flow rates of up to 10 muL/min, which corresponds to a linear flow velocity of 50 mm/s and far exceeds the flow velocities typical of the common analytical microchips. The function of the monolithic concentration device was first demonstrated using very dilute solutions of Coumarin 519. The performance in a more realistic application was then demonstrated with the enrichment of a hydrophobic tetrapeptide and also of green fluorescent protein for which an increase in concentration by a factor as high as 10(3) was achieved. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EO Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Frechet, JMJ (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. OI Frechet, Jean /0000-0001-6419-0163 FU NIGMS NIH HHS [GM-48364] NR 56 TC 289 Z9 298 U1 10 U2 92 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 NOV 1 PY 2001 VL 73 IS 21 BP 5088 EP 5096 DI 10.1021/ac0106288 PG 9 WC Chemistry, Analytical SC Chemistry GA 489LH UT WOS:000171992500023 PM 11721904 ER PT J AU Grate, JW Patrash, SJ Kaganove, SN Abraham, MH Wise, BM Gallagher, NB AF Grate, JW Patrash, SJ Kaganove, SN Abraham, MH Wise, BM Gallagher, NB TI Inverse least-squares modeling of vapor descriptors using polymer-coated surface acoustic wave sensor array responses SO ANALYTICAL CHEMISTRY LA English DT Article ID THICKNESS-SHEAR MODE; CHEMICALLY SENSITIVE INTERFACES; LOG K-VALUES; PARTITION-COEFFICIENTS; PIEZOELECTRIC-CRYSTALS; SORBENT COATINGS; ORGANIC VAPORS; OLIVE OIL; GAS; MICROSENSOR AB In previous work, it was shown that, in principle, vapor descriptors could be derived from the responses of an array of polymer-coated acoustic wave devices. This new chemometric classification approach was based on polymer/vapor interactions following the well-established linear solvation energy relationships (LSERs) and the surface acoustic wave (SAW) transducers being mass sensitive. Mathematical derivations were included and were supported by simulations. In this work, an experimental data set of polymer-coated SAW vapor sensors is investigated. The data set includes 20 diverse polymers tested against 18 diverse organic vapors. It is shown that interfacial adsorption can influence the response behavior of sensors with nonpolar polymers in response to hydrogen-bonding vapors; however, in general, most sensor responses are related to vapor interactions with the polymers. It is also shown that polymer-coated SAW sensor responses can be empirically modeled with LSERs, deriving an LSER for each individual sensor based on its responses to the 18 vapors. Inverse least-squares methods are used to develop models that correlate and predict vapor descriptors from sensor array responses. Successful correlations can be developed by multiple linear regression (MLR), principal components regression (PCR), and partial least-squares (PLS) regression. MLR yields the best fits to the training data, however cross-validation shows that prediction of vapor descriptors for vapors not in the training set is significantly more successful using PCR or PLS. In addition, the optimal dimension of the PCR and PLS models supports the dimensionality of the LSER formulation and SAW response models. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Eigenvector Res Inc, Manson, WA 98831 USA. UCL, Dept Chem, London WC1H OAJ, England. RP Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 65 TC 44 Z9 44 U1 1 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 EI 1520-6882 J9 ANAL CHEM JI Anal. Chem. PD NOV 1 PY 2001 VL 73 IS 21 BP 5247 EP 5259 DI 10.1021/ac010490t PG 13 WC Chemistry, Analytical SC Chemistry GA 489LH UT WOS:000171992500045 PM 11721926 ER PT J AU Alfonta, L Willner, I Throckmorton, DJ Singh, AK AF Alfonta, L Willner, I Throckmorton, DJ Singh, AK TI Electrochemical and quartz crystal microbalance detection of the cholera toxin employing horseradish peroxidase and GM1-functionalized liposomes SO ANALYTICAL CHEMISTRY LA English DT Article ID ENZYME ELECTRODES; AMPEROMETRIC BIOSENSORS; IMPEDANCE SPECTROSCOPY; COLORIMETRIC DETECTION; MOLECULAR RECOGNITION; INSOLUBLE PRODUCT; IMMUNOASSAY; GANGLIOSIDE; PRECIPITATION; TRANSDUCTION AB An ultrasensitive method for the detection of the cholera toxin (CT) using electrochemical or microgravimetric quartz crystal microbalance transduction means is described. Horseradish peroxidase (HRP) and GM1-functionalized liposomes act as catalytic recognition labels for the amplified detection of the cholera toxin based on highly specific recognition of CT by the ganglioside GM1. The sensing interface consists of monoclonal antibody against the B subunit of CT that is linked to protein G, assembled as a monolayer on an Au electrode or an Au/ quartz crystal. The CT is detected by a "sandwich-type" assay on the electronic transducers, where the toxin is first bound to the anti-CT-Ab and then to the HRP-GM1-ganglioside-functionalized liposome. The enzyme-labeled liposome mediates the oxidation of 4-chloronaphthol (2) in the presence of H2O2 to form the insoluble product 3 on the electrode support or the Au/quartz crystal. The biocatalytic precipitation of 3 provides the amplification route for the detection of the CT. Formation of the insulating film of 3 on the electrode increases the interfacial electron-transfer resistance, R-et, or enhances the electrode resistance, R', parameters that are quantitatively derived by Faradaic impedance measurements and chronopotentiometric analyses, respectively. Similarly, the precipitate 3 formed on the Au/quartz crystal results in a mass increase on the transducer that is reflected by a decrease in the resonance frequency of the crystal. The methods allow the detection of the CF with an unprecedented sensitivity that corresponds to 1.0 x 10(-13) M. C1 Hebrew Univ Jerusalem, Inst Chem, IL-91904 Jerusalem, Israel. Sandia Natl Labs, Chem & Radiat Detect Labs, Livermore, CA 94550 USA. RP Willner, I (reprint author), Hebrew Univ Jerusalem, Inst Chem, IL-91904 Jerusalem, Israel. RI Alfonta, Lital/B-6101-2012 OI Alfonta, Lital/0000-0002-3805-8625 NR 52 TC 134 Z9 141 U1 2 U2 19 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 NOV 1 PY 2001 VL 73 IS 21 BP 5287 EP 5295 DI 10.1021/ac010542e PG 9 WC Chemistry, Analytical SC Chemistry GA 489LH UT WOS:000171992500050 PM 11721931 ER PT J AU McClain, MA Culbertson, CT Jacobson, SC Ramsey, JM AF McClain, MA Culbertson, CT Jacobson, SC Ramsey, JM TI Flow cytometry of Escherichia coli on nucrifluidic devices SO ANALYTICAL CHEMISTRY LA English DT Article ID CAPILLARY-ELECTROPHORESIS; MICROCHIP; CELLS; CHIP; ELECTROPORATION; TRANSFORMATION; PERFORMANCE; PARTICLES; DNA AB Flow cytometry of the bacterium Escherichia coli was demonstrated on a microfabricated fluidic device (microchip). The channels were coated with poly(dimethylacrylamide) to prevent cell adhesion, and the cells were transported electrophoretically by applying potentials to the fluid reservoirs. The cells were electrophoretically focused at the channel cross and detected by coincident light scattering and fluorescence. The E. coli were labeled with a membrane-permeable nucleic acid stain (Syto15), a membrane-impermeable nucleic acid stain (propidium iodide), or a fluorescein-labeled antibody and counted at rates from 30 to 85 Hz. The observed labeling efficiencies for the dyes and antibody were greater than 94%. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ramsey, JM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. FU NCI NIH HHS [D98CA78858] NR 24 TC 178 Z9 184 U1 2 U2 30 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD NOV 1 PY 2001 VL 73 IS 21 BP 5334 EP 5338 DI 10.1021/ac010504v PG 5 WC Chemistry, Analytical SC Chemistry GA 489LH UT WOS:000171992500057 PM 11721938 ER PT J AU Smith, AB AF Smith, AB TI Fast-neutrons incident on holmium SO ANNALS OF NUCLEAR ENERGY LA English DT Article AB Differential neutron-scattering cross-sections of Ho-165 are measured at 40 or more scattering angles and at approximate to0.5 MeV incident-energy intervals from approximate to4.5-10.0 MeV. These results are combined with previously-reported neutron total and scattering cross-sections to construct a comprehensive experimental data base which is interpreted in the context of a coupled-channels model, with attention to the collective excitation of the K = 7/2(-) ground-state rotational band. Physical aspects are discussed and comparisons made with previous models reported in the literature and with the relevant portions of the ENDF/B-6 evaluated nuclear data file. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Technol Dev Div, Argonne, IL 60439 USA. RP Smith, AB (reprint author), Argonne Natl Lab, Technol Dev Div, Bldg D-362,9700 S Cass Ave, Argonne, IL 60439 USA. NR 53 TC 11 Z9 11 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0306-4549 J9 ANN NUCL ENERGY JI Ann. Nucl. Energy PD NOV PY 2001 VL 28 IS 17 BP 1745 EP 1758 DI 10.1016/S0306-4549(01)00015-9 PG 14 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 464CQ UT WOS:000170516000005 ER PT J AU Agron, PG Walker, RL Kinde, H Sawyer, SJ Hayes, DC Wollard, J Andersen, GL AF Agron, PG Walker, RL Kinde, H Sawyer, SJ Hayes, DC Wollard, J Andersen, GL TI Identification by subtractive hybridization of sequences specific for Salmonella enterica serovar Enteritidis SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID ENVIRONMENTAL SWABS; POULTRY HOUSES; UNITED-STATES; PLASMID; ASSAY; DNA; EPIDEMIOLOGY; TYPHIMURIUM; FIMBRIAE; STRAINS AB Salmonella enterica serovar Enteritidis, a major cause of food poisoning, can be transmitted to humans through intact chicken eggs when the contents have not been thoroughly cooked. Infection in chickens is asymptomatic; therefore, simple, sensitive, and specific detection methods are crucial for efforts to limit human exposure. Suppression subtractive hybridization was used to isolate DNA restriction fragments present in Salmonella serovar Enteritidis but absent in other bacteria found in poultry environments. Oligonucleotide primers to candidate regions were used in polymerase chain reactions to test 73 non-Enteritidis S. enterica isolates comprising 34 different serovars, including Dublin and Pullorum, two very close relatives of Enteritidis. A primer pair to one Salmonella difference fragment (termed Sdf I) clearly distinguished serovar Enteritidis from all other serovars tested, while two other primer pairs only identified a few non-Enteritidis strains. These primer pairs were also useful for the detection of a diverse collection of clinical and environmental Salmonella serovar Enteritidis isolates. In addition, five bacterial genera commonly found with Salmonella serovar Enteritidis were not detected. By treating total DNA with an exonuclease that degrades sheared chromosomal DNA but not intact circular plasmid DNA, it was shown that Sdf I is located on the chromosome. The Sdf I primers were used to screen a Salmonella serovar Enteritidis genomic library and a unique 4,060-bp region was defined. These results provide a basis for developing a rapid, sensitive, and highly specific detection system for Salmonella serovar Enteritidis and provide sequence information that may be relevant to the unique characteristics of this serovar. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. Univ Calif Davis, Sch Vet Med, Calif Anim Hlth & Food Safety Lab, Davis Branch, Davis, CA 95616 USA. Univ Calif Davis, Sch Vet Med, San Bernardino Branch, Calif Anim Hlth & Food Safety Lab, San Bernardino, CA 92408 USA. RP Andersen, GL (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, 7000 E Ave,L-441, Livermore, CA 94550 USA. RI Andersen, Gary/G-2792-2015 OI Andersen, Gary/0000-0002-1618-9827 NR 24 TC 83 Z9 89 U1 0 U2 9 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD NOV PY 2001 VL 67 IS 11 BP 4984 EP 4991 DI 10.1128/AEM.67.11.4984-4991.2001 PG 8 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 488BL UT WOS:000171914100005 PM 11679316 ER PT J AU Lu, NP Mason, CFV AF Lu, NP Mason, CFV TI Sorption-desorption behavior of strontium-85 onto montmorillonite and silica colloids SO APPLIED GEOCHEMISTRY LA English DT Article AB Strontium-90 (Sr-90) is one of the major radioactive contaminants found in DP Canyon at Los Alamos, New Mexico, USA. Radioactive surveys found that Sr-90 is present in surface water and shallow alluvial groundwater environments in Los Alamos National laboratory (LANL). Colloids may influence the transport of this radionuclide in surface and groundwater environments in LANL. In this study, the authors investigated the sorption/desorption behavior of radioactive Sr on Ca-montmorillonite and silica colloids, and the effect of ionic strength of water on the sorption of Sr. Laboratory batch sorption experiments were conducted using Sr-85 as a surrogate for Sr-90. Groundwater, collected from Well LAUZ-1 at DP Canyon and from Well J-13 at Yucca Mountain, Nevada, and deionized water, were used. The results show that 92-100% of the Sr-85 was rapidly adsorbed onto Ca-montmorillonite colloids in all three waters. Adsorption of Sr-85 onto silica colloids varied among the three waters. The ionic strength and Ca2+ concentration in groundwater significantly influence the adsorption of Sr-85 onto silica colloids. Desorption of Sr-85 from Ca-montmorillonite colloids is slower than from silica colloids. Desorption of Sr-85 from silica colloids was faster in LAUZ-1 groundwater than in J-13 groundwater and deionized water. The results suggest that clay and silica colloids may facilitate the transport of Sr along potential flowpaths from DP Canyon to Los Alamos Canyon. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Los Alamos Natl Lab, EET, Environm Div, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RP Lu, NP (reprint author), Los Alamos Natl Lab, EET, Environm Div, MS J 514, Los Alamos, NM 87545 USA. NR 27 TC 46 Z9 48 U1 4 U2 30 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0883-2927 J9 APPL GEOCHEM JI Appl. Geochem. PD NOV PY 2001 VL 16 IS 14 BP 1653 EP 1662 DI 10.1016/S0883-2927(01)00060-9 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 469XL UT WOS:000170841300007 ER PT J AU Seely, JF Montcalm, C Baker, S Bajt, S AF Seely, JF Montcalm, C Baker, S Bajt, S TI High-efficiency MoRu-Be multilayer-coated gratings operating near normal incidence in the 11.1-12.0-nm wavelength range SO APPLIED OPTICS LA English DT Article ID X-RAY; REGION; MO/SI; FILMS AB MoRu-Be multilayer coatings were applied to two diffraction gratings for the purpose of enhancing their normal-incidence efficiency in the 11.1-12.0-nm wavelength range. The grating substrates were replicas of a holographic master grating that had a blazed groove profile with 2400 grooves/mm and a 2-m radius of curvature. The relatively low average microroughness (0.8 nm) of the grating surfaces contributed to the relatively high groove efficiency of the grating substrates and the reflectance of the MoRu-Be multilayer coatings. The peak efficiency, measured with synchrotron radiation, was 10.4% in the second diffraction order at a wavelength of 11.37 nm. C1 USN, Res Lab, Div Space Sci, Washington, DC 20375 USA. Lawrence Livermore Natl Lab, Dept Informat Sci & Technol, Livermore, CA 94551 USA. RP Seely, JF (reprint author), USN, Res Lab, Div Space Sci, Code 7674, Washington, DC 20375 USA. EM john.seely@nrl.navy.mil RI Bajt, Sasa/G-2228-2010 NR 22 TC 12 Z9 12 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD NOV 1 PY 2001 VL 40 IS 31 BP 5565 EP 5574 DI 10.1364/AO.40.005565 PG 10 WC Optics SC Optics GA 487BH UT WOS:000171853400001 PM 18364842 ER PT J AU Gahagan, KT Scrymgeour, DA Casson, JL Gopalan, V Robinson, JM AF Gahagan, KT Scrymgeour, DA Casson, JL Gopalan, V Robinson, JM TI Integrated high-power electro-optic lens and large-angle deflector SO APPLIED OPTICS LA English DT Article ID MATCHED 2ND-HARMONIC GENERATION; ELECTRIC-FIELD APPLICATION; DOMAIN INVERSION; BEAM DEFLECTOR; LITAO3; CRYSTALS; PROPAGATION; SCANNERS; LINBO3 AB We present a theoretical discussion and experimental demonstration of what to our knowledge is a novel integrated electro-optic lens and beam deflector fabricated in lithium tantalate. The cylindrical lens collimates Gaussian beams as small as 4 mum in diameter, whereas the independently controlled deflector is capable of scanning the collimated beam through an angular range of nearly 20 degrees. (C) 2001 Optical Society of America. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Penn State Univ, University Pk, PA 16802 USA. RP Gahagan, KT (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM gahagankt@corning.com RI Scrymgeour, David/C-1981-2008 NR 18 TC 20 Z9 23 U1 0 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD NOV 1 PY 2001 VL 40 IS 31 BP 5638 EP 5642 DI 10.1364/AO.40.005638 PG 5 WC Optics SC Optics GA 487BH UT WOS:000171853400011 PM 18364852 ER PT J AU Haegel, NM Schwartz, WR Zinter, J White, AM Beeman, JW AF Haegel, NM Schwartz, WR Zinter, J White, AM Beeman, JW TI Origin of the hook effect in extrinsic photoconductors SO APPLIED OPTICS LA English DT Article ID TRANSIENT-RESPONSE; SEMICONDUCTORS; MODEL AB The response of extrinsic photoconductors to a step change in incident photon flux has long been known to exhibit a sharp transient feature, particularly at higher signal levels, known as the hook effect. We demonstrate experimentally and theoretically that the hook effect can be due to reduced illumination adjacent to the injecting contact. This nonuniformity can be produced by the transverse illumination of the detector that is common for far-infrared Ge:Ga devices. The hook effect has been demonstrated to be either present or absent in the same Ge:Ga photoconductor, at comparable signal size, depending on the nature of the contact illumination. Numerical finite-difference calculations of the transient response support this explanation and produce features that replicate the. experimental results. (C) 2001 Optical Society of America. C1 Fairfield Univ, Dept Phys, Fairfield, CT 06430 USA. White Numer Consulting LTD, Malvern WR14 3QW, Worcs, England. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Haegel, NM (reprint author), Fairfield Univ, Dept Phys, Fairfield, CT 06430 USA. EM nhaegel@fari1.fairfield.edu NR 13 TC 9 Z9 9 U1 1 U2 5 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD NOV 1 PY 2001 VL 40 IS 31 BP 5748 EP 5754 DI 10.1364/AO.40.005748 PG 7 WC Optics SC Optics GA 487BH UT WOS:000171853400025 PM 18364866 ER PT J AU Bandong, BB Volpe, AM Esser, BK Bianchini, GM AF Bandong, BB Volpe, AM Esser, BK Bianchini, GM TI Pre-concentration and measurement of low levels of gamma-ray emitting radioisotopes in coastal waters SO APPLIED RADIATION AND ISOTOPES LA English DT Article DE radioisotopes; extraction methodology; seawater ID INDUSTRIAL-SCALE REMOVAL; HEXACYANOFERRATE EXCHANGER; COMPOSITE SORBENTS; ION-EXCHANGE; CESIUM; RADIONUCLIDES; SORPTION; SHELF AB We describe extensive testing of a large-volume, high-speed water sampler for the concentration and measurement of radionuclides using high-resolution gamma ray spectrometry. The sampler processed hundreds to thousands of liters of natural waters with variable suspended sediment and salinity loads at flow rates of 10-201/min. Extraction of most radionuclides in the water column was accomplished through the combination of physical filtration down to 0.1 mum particle size and chemical separation of dissolved species on cellulose-based inorganic sorbent beds without recourse to complex, or hazardous chemistry. Performance and extraction efficiencies for suites of radioisotopes were deter-mined in the laboratory and in the field with river and coastal ocean water samples. Extraction and recovery efficiencies are better than 90% for most fission and activation product radioisotopes. This methodology has broad application to the study of the distribution and fate of radioisotopes in coastal waterways. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Lawrence Livermore Natl Lab, Analyt & Nucl Chem Div, Livermore, CA 94550 USA. RP Volpe, AM (reprint author), Lawrence Livermore Natl Lab, Analyt & Nucl Chem Div, L-231, Livermore, CA 94550 USA. RI Esser, Bradley/G-4283-2010 OI Esser, Bradley/0000-0002-3219-4298 NR 29 TC 14 Z9 14 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD NOV PY 2001 VL 55 IS 5 BP 653 EP 665 DI 10.1016/S0969-8043(01)00081-1 PG 13 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 470LM UT WOS:000170873500008 PM 11573799 ER PT J AU Worley, CG Havrilla, GJ Dunn, PS AF Worley, CG Havrilla, GJ Dunn, PS TI Quantification of large scale micro-X-ray fluorescence elemental images SO APPLIED SPECTROSCOPY LA English DT Article DE micro-X-ray fluorescence; quantitative imaging; elemental imaging; niobium; uranium ID SPECTROMETRY; SPECTROSCOPY; LECTURE; SYSTEM; XRF AB Niobium is commonly alloyed with uranium to prevent surface oxidation, and determining how the niobium concentration is distributed throughout a sample is useful in explaining observed material properties. The niobium concentration distribution was determined across the surface of depleted uranium samples using, micro-X-ray fluorescence (MXRF). To date, MRF has been employed primarily, as a qualitative toot for determining relative differences in elemental concentrations across a sample surface. Here, a process was developed to convert qualitative MXRF niobium distribution images from depleted uranium samples into images displaying concentration values. Thus, MXRF was utilized to determine elemental concentrations across a surface in a manner similar to that of the established method of electron microprobe X-ray analysis (EMPA). However, MXRF can provide such information from relatively large sample areas many cm(2) in size that are too large to examine by the higher spatial resolution technique of EMPA. Although the sample surfaces were polished to the same degree as the standards, little or no sample preparation should be necessary for sample systems where a high energy analyte XRF line can be used for imaging. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Worley, CG (reprint author), Los Alamos Natl Lab, MS G740, Los Alamos, NM 87545 USA. NR 30 TC 3 Z9 3 U1 3 U2 4 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD NOV PY 2001 VL 55 IS 11 BP 1448 EP 1454 DI 10.1366/0003702011953928 PG 7 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 494UQ UT WOS:000172304600003 ER PT J AU Damm, CJ Lucas, D Sawyer, RF Koshland, CP AF Damm, CJ Lucas, D Sawyer, RF Koshland, CP TI Real-time measurement of combustion generated particles with photofragmentation-fluorescence SO APPLIED SPECTROSCOPY LA English DT Article DE particulate monitoring; laser diagnostics; aerosol; excimer; combustion ID LASER-INDUCED INCANDESCENCE; FRAGMENTATION FLUORESCENCE; CAVITY RINGDOWN; DIESEL-ENGINES; SOOT; SPECTROSCOPY; VAPORIZATION; DIAGNOSTICS; SCATTERING; EMISSIONS AB Excimer laser fragmentation-fluorescence spectroscopy (ELFFS) is a viable technique for real-time monitoring of carbonaceous particles in combustion exhausts. The exhaust from a single-cylinder two-stroke engine is diluted and diverted into the laser interrogation region, resulting in a particle concentration of approximately I X 107/cm(3). Light from a 193 nm ArF laser photofragments the particles and then produces fluorescence from the atomic carbon fragments at 248 nm, CH fragments at 431 nm, and C-2, fragments at 468 nm. The atomic carbon fluorescence signal is proportional to the number concentration of particles in the laser interrogation region. The 100-shot (1 s) detection limit for particles in the exhaust is 1 mg/m(3), expressed as a mass concentration of particulate matter. Interferences from carbon monoxide and carbon dioxide are neg. ligible. The relative fluorescence yield at 248 nm is four times greater from particles than from the gas phase hydrocarbons present in the exhaust. This high yield suggests that the gas phase hydrocarbon interference would not be problematic for measurements of diesel exhaust, where the ratio of particulate carbon to gas phase hydrocarbon is high. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. RP Damm, CJ (reprint author), Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. RI Sawyer, Robert/B-5013-2014 NR 32 TC 10 Z9 10 U1 0 U2 4 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD NOV PY 2001 VL 55 IS 11 BP 1478 EP 1482 DI 10.1366/0003702011953892 PG 5 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 494UQ UT WOS:000172304600007 ER PT J AU Ganguly, S Biringer, KL AF Ganguly, S Biringer, KL TI Nuclear crisis stability in south Asia SO ASIAN SURVEY LA English DT Article C1 Univ Texas, Dept Asian Studies, Austin, TX 78712 USA. Univ Texas, Dept Govt, Austin, TX 78712 USA. Sandia Natl Labs, Cooperat Monitoring Ctr, Albuquerque, NM 87185 USA. RP Ganguly, S (reprint author), Univ Texas, Dept Asian Studies, Austin, TX 78712 USA. NR 24 TC 1 Z9 1 U1 0 U2 0 PU UNIV CALIF PRESS PI BERKELEY PA C/O JOURNALS DIVISION, 2000 CENTER ST, STE 303, BERKELEY, CA 94704-1223 USA SN 0004-4687 J9 ASIAN SURV JI Asian Surv. PD NOV-DEC PY 2001 VL 41 IS 6 BP 907 EP 924 DI 10.1525/as.2001.41.6.907 PG 18 WC Area Studies SC Area Studies GA 523XL UT WOS:000173982800002 ER PT J AU Eisenstein, DJ Annis, J Gunn, JE Szalay, AS Connolly, AJ Nichol, RC Bahcall, NA Bernardi, M Burles, S Castander, FJ Fukugita, M Hogg, DW Ivezic, Z Knapp, GR Lupton, RH Narayanan, V Postman, M Reichart, DE Richmond, M Schneider, DP Schlegel, DJ Strauss, MA SubbaRao, M Tucker, DL Vanden Berk, D Vogeley, MS Weinberg, DH Yanny, B AF Eisenstein, DJ Annis, J Gunn, JE Szalay, AS Connolly, AJ Nichol, RC Bahcall, NA Bernardi, M Burles, S Castander, FJ Fukugita, M Hogg, DW Ivezic, Z Knapp, GR Lupton, RH Narayanan, V Postman, M Reichart, DE Richmond, M Schneider, DP Schlegel, DJ Strauss, MA SubbaRao, M Tucker, DL Vanden Berk, D Vogeley, MS Weinberg, DH Yanny, B TI Spectroscopic target selection for the Sloan Digital Sky Survey: The luminous red galaxy sample SO ASTRONOMICAL JOURNAL LA English DT Article DE cosmology : observations; galaxies : clusters : general; galaxies : distances and redshifts; galaxies : elliptical and lenticular, cD; large-scale structure of universe; surveys ID BRIGHTEST CLUSTER GALAXIES; BAND HUBBLE DIAGRAM; DISTANT CLUSTERS; EVOLUTION; COLORS; SPECTROPHOTOMETRY; MAGNITUDES; POPULATION; REDSHIFTS; MODEL AB We describe the target selection and resulting properties of a spectroscopic sample of luminous red galaxies (LRGs) from the imaging data of the Sloan Digital Sky Survey (SDSS). These galaxies are selected on the basis of color and magnitude to yield a sample of luminous intrinsically red galaxies that extends fainter and farther than the main flux-limited portion of the SDSS galaxy spectroscopic sample. The sample is designed to impose a passively evolving luminosity and rest-frame color cut to a redshift of 0.38. Additional, yet more luminous red galaxies are included to a redshift of similar to0.5. Approximately 12 of these galaxies per square degree are targeted for spectroscopy, so the sample will number over 100,000 with the full survey. SDSS commissioning data indicate that the algorithm efficiently selects luminous (M-g* approximate to -21.4) red galaxies, that the spectroscopic success rate is very high, and that the resulting set of galaxies is approximately volume limited out to z = 0.38. When the SDSS is complete, the LRG spectroscopic sample will fill over 1 h(-3) Gpc(3) with an approximately homogeneous population of galaxies and will therefore be well suited to studies of large-scale structure and clusters out to z = 0.5. C1 Inst Adv Study, Princeton, NJ 08540 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15232 USA. Yale Univ, New Haven, CT 06520 USA. Univ Chile, Santiago, Chile. Univ Tokyo, Inst Cosm Ray Res, Tokyo 1888502, Japan. NYU, Dept Phys, New York, NY 10003 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. CALTECH, Palomar Observ, Pasadena, CA 91125 USA. Rochester Inst Technol, Dept Phys, Rochester, NY 14623 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Drexel Univ, Dept Phys, Philadelphia, PA 19104 USA. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Eisenstein, DJ (reprint author), Inst Adv Study, Olden Lane, Princeton, NJ 08540 USA. OI Hogg, David/0000-0003-2866-9403 NR 52 TC 730 Z9 733 U1 1 U2 6 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 2001 VL 122 IS 5 BP 2267 EP 2280 DI 10.1086/323717 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 491AP UT WOS:000172086100009 ER PT J AU Odenkirchen, M Grebel, EK Harbeck, D Dehnen, W Rix, HW Newberg, HJ Yanny, B Holtzman, J Brinkmann, J Chen, B Csabai, I Hayes, JJE Hennessy, G Hindsley, RB Ivezic, Z Kinney, EK Kleinman, SJ Long, D Lupton, RH Neilsen, EH Nitta, A Snedden, SA York, DG AF Odenkirchen, M Grebel, EK Harbeck, D Dehnen, W Rix, HW Newberg, HJ Yanny, B Holtzman, J Brinkmann, J Chen, B Csabai, I Hayes, JJE Hennessy, G Hindsley, RB Ivezic, Z Kinney, EK Kleinman, SJ Long, D Lupton, RH Neilsen, EH Nitta, A Snedden, SA York, DG TI New insights on the Draco dwarf spheroidal galaxy from the Sloan Digital sky Survey: A larger radius and no tidal tails SO ASTRONOMICAL JOURNAL LA English DT Article DE galaxies : dwarf; galaxies : individual (Draco); galaxies : structure; Local Group ID TO-LIGHT RATIOS; SURVEY COMMISSIONING DATA; RR-LYRAE STARS; URSA-MINOR; DARK-MATTER; GIANT STARS; HALO; PHOTOMETRY; KINEMATICS; DISTANCES AB We have investigated the spatial extent and structure of the Draco dwarf spheroidal galaxy by using deep wide-field multicolor CCD photometry from the Sloan Digital Sky Survey (SDSS). Our study covers an area of 27 deg(2) around the center of the Draco dwarf and reaches 2 mag below the level of Draco's horizontal branch. The SDSS photometry allows very effective filtering in color-magnitude space. With such filtering the density of the foreground of Galactic field stars is decreased by more than an order of magnitude, and the stellar population of the Draco dwarf galaxy thus stands out with much higher contrast than in former investigations. We show that the spatial distribution of Draco's red giants, red horizontal-branch stars, and subgiants down to i* = 21.7 mag does not provide evidence for the existence of tidally induced tails or a halo of unbound stars. The projected surface density of the dwarf galaxy is flattened with a nearly constant ellipticity of 0.29 +/- 0.02 at position angle 88 degrees +/- 3 degrees. The radial profile can be fitted by King models, as well as by a generalized exponential. Using the empirical King profile, the core radius and the limiting (or tidal) radius along the major axis are r(c) = 7.'7 and r(t) = 40.'1, respectively; the latter means that the size of the Draco dwarf galaxy is 40% larger than previously measured. Fitting the profile of King's theoretical models yields a still larger limiting radius of r(t) = 49.'5. There is no clear indication of a taillike extension of the Draco population beyond this radius. A break in the radial surface density profile, which might indicate a halo of extratidal stars, is also not found in our Draco data. We conclude that down to the above magnitude limit tidal effects can exist only at a level of 10(-3) of the central surface density of Draco or below. The regular structure of Draco found from the new data argues against its being a portion of an unbound tidal stream and lends support to the assumption of dynamical equilibrium, which is the basis for mass estimation. The changes in the values for the core radius and limiting radius imply that the total mass of Draco is higher by more than a factor of 2. Using a King spherical model of equivalent size as a reference and adopting a line-of-sight velocity dispersion of either 10.7 or 8.5 km s(-1), we derive estimates of the total mass within radius of (3.5 +/- 0.7) x 10(7) M. and (2.2 +/- 0.5) x 10(7) M., respectively. From the combined i-band flux of all possible Draco members that lie within major-axis radius rt we determine the total luminosity of the Draco dwarf galaxy as (L/L.)(i) = (2.4 +/- 0.5) x 10(5). This includes corrections for the flux of the foreground stars and the unseen fainter part of the Draco population. We thus obtain overall mass-to-light ratios of M/L-i of 146 +/- 42, or 92 +/- 28 in solar units. In summary, our results strengthen the case for a strongly dark matter-dominated, bound stellar system. C1 Max Planck Inst Astron, D-69117 Heidelberg, Germany. Rensselaer Polytech Inst, Dept Phys Appl Phys & Astron, Troy, NY 12180 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. New Mexico State Univ, Dept Astron, Las Cruces, NM 88003 USA. Apache Point Observ, Sunspot, NM 88349 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. USN Observ, Washington, DC 20392 USA. USN, Res Lab, Washington, DC 20375 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. RP Odenkirchen, M (reprint author), Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany. RI Csabai, Istvan/F-2455-2012; OI Csabai, Istvan/0000-0001-9232-9898 NR 57 TC 111 Z9 111 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 2001 VL 122 IS 5 BP 2538 EP 2553 DI 10.1086/323715 PG 16 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 491AP UT WOS:000172086100023 ER PT J AU Ivezic, Z Tabachnik, S Rafikov, R Lupton, RH Quinn, T Hammergren, M Eyer, L Chu, J Armstrong, JC Fan, XH Finlator, K Geballe, TR Gunn, JE Hennessy, GS Knapp, GR Leggett, SK Munn, JA Pier, JR Rockosi, CM Schneider, DP Strauss, MA Yanny, B Brinkmann, J Csabai, I Hindsley, RB Kent, S Lamb, DQ Margon, B McKay, TA Smith, JA Waddel, P York, DG AF Ivezic, Z Tabachnik, S Rafikov, R Lupton, RH Quinn, T Hammergren, M Eyer, L Chu, J Armstrong, JC Fan, XH Finlator, K Geballe, TR Gunn, JE Hennessy, GS Knapp, GR Leggett, SK Munn, JA Pier, JR Rockosi, CM Schneider, DP Strauss, MA Yanny, B Brinkmann, J Csabai, I Hindsley, RB Kent, S Lamb, DQ Margon, B McKay, TA Smith, JA Waddel, P York, DG CA SDSS Collaboration TI Solar system objects observed in the Sloan Digital Sky Survey commissioning data SO ASTRONOMICAL JOURNAL LA English DT Article DE Kuiper belt; minor planets, asteroids; solar system : general ID KUIPER-BELT OBJECTS; EARTH-APPROACHING ASTEROIDS; FALL EQUATORIAL STRIPE; SIZE DISTRIBUTION; MAGNITUDE DISTRIBUTIONS; QUASARS; STARS; SPECTROPHOTOMETRY; CLASSIFICATION; POPULATIONS AB We discuss measurements of the properties of similar to 13,000 asteroids detected in 500 deg(2) of sky in the Sloan Digital Sky Survey (SDSS) commissioning data. The moving objects are detected in the magnitude range 14 18). The observed counts imply that there are about 670,000 objects with D>1 km in the asteroid belt, or up to 3 times less than previous estimates. The revised best estimate for the impact rate of the so-called "killer" asteroids (D>1 km) is about 1 every 500,000 yr, uncertain to within a factor of 2. We predict that by its completion SDSS will obtain about 100,000 near simultaneous five-band measurements for a subset drawn from 340,000 asteroids brighter than r* <21.5 at opposition. Only about a third of these asteroids have been previously observed, and usually in just one band. The distribution of main-belt asteroids in the four-dimensional SDSS color space is bimodal, and the two groups can be associated with S- (rocky) and C-(carbonaceous) type asteroids. A strong bimodality is also seen in the heliocentric distribution of asteroids : the inner belt is dominated by S-type asteroids centered at R2.8 AU, while C-type asteroids, centered at R similar to 3.2 AU, dominate the outer belt. The median color of each class becomes bluer by about 0.03 mag AU(-1) as the heliocentric distance increases. The observed number ratio of S and C asteroids in a sample with r* <21.5 is 1.5 : 1, while in a sample limited by absolute magnitude it changes from 4: 1 at 2 AU, to 1: 3 at 3.5 AU. In a size-limited sample with D>1 km, the number ratio of S and C asteroids in the entire main belt is 1: 2.3. The colors of Hungarias, Mars crossers, and near-Earth objects, selected by their velocity vectors, are more similar to the C-type than to S-type asteroids. In about 100 deg(2) of sky along the celestial equator observed twice 2 days apart, we find one plausible Kuiper belt object (KBO) candidate, in agreement with the expected KBO surface density. The colors of the KBO candidate are significantly redder than the asteroid colors, in agreement with colors of known KBOs. We explore the possibility that SDSS data can be used to search for very red, previously uncataloged asteroids observed by 2MASS, by extracting objects without SDSS counterparts. We do not find evidence for a significant population of such objects; their contribution is no more than 10% of the asteroid population. C1 Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Ramapo High Sch, Spring Valley, NY 10977 USA. Joint Astron Ctr, United Kingdom Infrared Telescope, Hilo, HI 96720 USA. USN Observ, Washington, DC 20392 USA. USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Apache Point Observ, Sunspot, NM 88349 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Eotvos Lorand Univ, Dept Phys Complex Syst, H-1117 Budapest, Hungary. USN, Remote Sensing Div, Res Lab, Washington, DC 20375 USA. Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA. NASA, USRA, SOFIA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Ivezic, Z (reprint author), Princeton Univ Observ, Peyton Hall, Princeton, NJ 08544 USA. RI Margon, Bruce/B-5913-2012; Csabai, Istvan/F-2455-2012; McKay, Timothy/C-1501-2009; Finlator, Kristian/M-4809-2014; OI McKay, Timothy/0000-0001-9036-6150; Finlator, Kristian/0000-0002-0496-1656; Armstrong, John/0000-0003-2009-1459; Csabai, Istvan/0000-0001-9232-9898; Leggett, Sandy/0000-0002-3681-2989 NR 77 TC 239 Z9 241 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD NOV PY 2001 VL 122 IS 5 BP 2749 EP 2784 DI 10.1086/323452 PG 36 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 491AP UT WOS:000172086100043 ER PT J AU Gozdziewski, K Bois, E Maciejewski, AJ Kiseleva-Eggleton, L AF Gozdziewski, K Bois, E Maciejewski, AJ Kiseleva-Eggleton, L TI Global dynamics of planetary systems with the MEGNO criterion SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE celestial mechanics, stellar dynamics; methods : numerical, N-body simulations; planetary systems; stars : individual (upsilon Andromedae) ID UPSILON-ANDROMEDAE; STABILITY; MOTION; CHAOS AB In this paper we apply a new technique alternative to the numerically computed Lyapunov Characteristic Number (LCN) for studying the dynamical behaviour of planetary systems in the framework of the gravitational N-body problem. The method invented by P. Cincotta and C. Simo is called the Mean Exponential Growth of Nearby Orbits (MEGNO). It provides an efficient way for investigation of the fine structure of the phase space and its regular and chaotic components in any conservative Hamiltonian system. In this work we use it to study the dynamical behaviour of the multidimensional planetary systems. We investigate the recently discovered upsilon And planetary system, which consists of a star of 1.3 M. and three Jupiter-size planets. The two outermost planets have eccentric orbits. This system appears to be one of the best candidates for dynamical studies. The mutual gravitational interaction between the two outermost planets is strong. Moreover the system can survive on a stellar evolutionary time scale as it is claimed by some authors (e.g., Rivera & Lissauer 2000b). As the main methodological result of this work, we confirm important properties of the MEGNO criterion such as its fast convergence, and short motion times (of the order of 10(4) times the longest orbital period) required to distinguish between regular and chaotic behaviors. Using the MEGNO technique we found that the presence of the innermost planet may cause the whole system to become chaotic with the Lyapunov time scale of the order of 10(3)-10(4) yr only. Chaos does not induce in this case visible irregular changes of the orbital elements, and therefore its presence can be overlooked by studying variations of the elements. We confirm explicitly the strong and sensitive dependence of the dynamical behaviour on the companion masses. C1 Observ Bordeaux, CNRS, UMR 5804, INSU, F-33270 Floirac, France. Nicholas Copernicus Univ, Torun Ctr Astron, PL-87100 Torun, Poland. Zielona Gora Univ, Inst Astron, PL-65265 Zielona Gora, Poland. IGPP, LLNL, Livermore, CA 94550 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Gozdziewski, K (reprint author), Observ Bordeaux, CNRS, UMR 5804, INSU, BP 89, F-33270 Floirac, France. EM chris@astri.uni.torun.pl RI Gozdziewski, Krzysztof/D-6291-2014 OI Gozdziewski, Krzysztof/0000-0002-8705-1577 NR 32 TC 65 Z9 66 U1 1 U2 2 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD NOV PY 2001 VL 378 IS 2 BP 569 EP 586 DI 10.1051/0004-6361:20011189 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 485TK UT WOS:000171779800022 ER PT J AU Osborne, JP Borozdin, KN Trudolyubov, SP Priedhorsky, WC Soria, R Shirey, R Hayter, C La Palombara, N Mason, K Molendi, S Paerels, F Pietsch, W Read, AM Tiengo, A Watson, MG West, RG AF Osborne, JP Borozdin, KN Trudolyubov, SP Priedhorsky, WC Soria, R Shirey, R Hayter, C La Palombara, N Mason, K Molendi, S Paerels, F Pietsch, W Read, AM Tiengo, A Watson, MG West, RG TI The central region of M 31 observed with XMM-Newton - II. Variability of the individual sources SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE galaxies : individual : M 31; galaxies : spiral; galaxies : general; X-rays : galaxies ID PHOTON IMAGING CAMERA; X-RAY OBSERVATIONS; ROSAT PSPC SURVEY; M31; POPULATION; EMISSION; BINARIES; NOVAE AB We present the results of a study of the variability of X-ray sources in the central 30' of the nearby Andromeda Galaxy (M 31) based on XMM-Newton Performance Verification observations. Two observations of this field, with a total exposure time of about 50 ks, were performed in June and December of 2000. We found 116 sources brighter than a limiting luminosity of 6 x 10(35) erg s(-1) (0.3-12 keV, d = 760 kpc). For the similar to 60 brightest sources, we searched for periodic and non-periodic variability; at least 15% of these sources appear to be variable on a time scale of several months. We discovered a new bright transient source similar to2.9' from the nucleus in the June observation; this source faded significantly and was no longer detected in December. The behaviour of the object is similar to a handful of Galactic LMXB transients, most of which are supposed to harbor black holes. We detected pulsations with a period of similar to 865 s from a source with a supersoft spectrum. The flux of this source decreased significantly between the two XMM observations. The detected period is unusually short and points to a rapidly spinning magnetized white dwarf. The high luminosity and transient nature of the source suggest its possible identification with classical or symbiotic nova, some of which were observed earlier as supersoft sources. C1 Los Alamos Natl Lab, NIS Div, Los Alamos, NM 87545 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. ESA, VILSPA, XMM Newton SOC, Madrid 28080, Spain. Ist Fis Cosm G Occhialini, I-20133 Milan, Italy. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. Max Planck Inst Extraterr Phys, D-85741 Garching, Germany. RP Los Alamos Natl Lab, NIS Div, POB 1663, Los Alamos, NM 87545 USA. EM kbor@lanl.gov OI La Palombara, Nicola/0000-0001-7015-6359; Priedhorsky, William/0000-0003-0295-9138; Tiengo, Andrea/0000-0002-6038-1090; Molendi, Silvano/0000-0002-2483-278X NR 31 TC 57 Z9 57 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD NOV PY 2001 VL 378 IS 3 BP 800 EP 805 DI 10.1051/0004-6361:20011228 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487VA UT WOS:000171897200010 ER PT J AU Borgani, S Rosati, P Tozzi, P Stanford, SA Eisenhardt, PR Lidman, C Holden, B Della Ceca, R Norman, C Squires, G AF Borgani, S Rosati, P Tozzi, P Stanford, SA Eisenhardt, PR Lidman, C Holden, B Della Ceca, R Norman, C Squires, G TI Measuring Omega(m) with the ROSAT Deep Cluster Survey SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmological parameters; cosmology : theory; dark matter; galaxies : clusters : general X-rays : galaxies ID X-RAY-CLUSTERS; GALAXY CLUSTERS; HIGH-REDSHIFT; TEMPERATURE FUNCTION; COOLING FLOWS; EVOLUTION; MASS; CONSTRAINTS; LUMINOSITY; PARAMETERS AB We analyze the ROSAT Deep Cluster Survey (RDCS) to derive cosmological constraints from the evolution of the cluster X-ray luminosity distribution. The sample contains 103 galaxy clusters out to z similar or equal to 0.85 and flux limit F-lim = 3 x 10(-14) ergs s(-1) cm(-2) (RDCS-3) in the [0.5E2.0] keV energy band, with a high-redshift extension containing four clusters at 0.90 less than or equal to z less than or equal to 1.26 and brighter than F-lim = 1 x 10(-14) ergs s(-1) cm(-2) (RDCS-1). We assume cosmological models to be speciDed by the matter density parameter Omega (m), the rms fluctuation amplitude at the 8 h(-1) Mpc scale sigma (8), and the shape parameter for the cold dark matter-like power spectrum Gamma. Model predictions for the cluster mass function are converted into the X-ray luminosity function in two steps. First, we convert mass into intracluster gas temperature by assuming hydrostatic equilibrium. Then, temperature is converted into X-ray luminosity by using the most recent data on the L-X-T-X relation for nearby and distant clusters. These include the Chandra data for six distant clusters at 0.57 less than or equal to z less than or equal to 1.27. From RDCS-3 we find Omega (m) = 0.35(-0.10)(+0.13) and sigma (8) = 0.66(-0.05)(+0.06) for a spatially flat universe with a cosmological constant, with no significant constraint on Gamma (errors correspond to 1 sigma confidence levels for three fitting parameters). Even accounting for both theoretical and observational uncertainties in the mass-X-ray luminosity conversion, an Einstein-de Sitter model is always excluded at far more than the 3 sigma level. We also show that the number of X-ray-bright clusters in RDCS-1 at z >0.9 is expected from the evolution inferred at z <0.9 data. C1 Univ Trieste, Dipartimento Astron, Ist Nazl Fis Nucl, Sez Trieste, I-34100 Trieste, Italy. Univ Perugia, Dipartimento Fis, Ist Nazl Fis Nucl, Sez Perugia, I-06123 Perugia, Italy. European So Observ, D-85748 Garching, Germany. Osserv Astron Trieste, I-34131 Trieste, Italy. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94551 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Osserv Astron Brera, I-20121 Milan, Italy. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. CALTECH, Dept Astron, Pasadena, CA 91125 USA. RP Borgani, S (reprint author), Univ Trieste, Dipartimento Astron, Ist Nazl Fis Nucl, Sez Trieste, Via Tiepolo 11, I-34100 Trieste, Italy. OI Borgani, Stefano/0000-0001-6151-6439 NR 68 TC 219 Z9 219 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 2001 VL 561 IS 1 BP 13 EP 21 DI 10.1086/323214 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487PC UT WOS:000171883600002 ER PT J AU Arav, N De Kool, M Korista, KT Crenshaw, DM Van Breugel, W Brotherton, M Green, RF Pettini, M Wills, B De Vries, W Becker, B Brandt, WN Green, P Junkkarinen, VT Koratkar, A Laor, A Laurent-Muehleisen, SA Mathur, S Murray, N AF Arav, N De Kool, M Korista, KT Crenshaw, DM Van Breugel, W Brotherton, M Green, RF Pettini, M Wills, B De Vries, W Becker, B Brandt, WN Green, P Junkkarinen, VT Koratkar, A Laor, A Laurent-Muehleisen, SA Mathur, S Murray, N TI HST STIS observations of PG 0946+301: The highest quality UV spectrum of a BALQSO SO ASTROPHYSICAL JOURNAL LA English DT Article DE quasars : absorption lines; quasars : individual (PG 0946+301); ultraviolet : galaxies ID BROAD ABSORPTION-LINE; QUASI-STELLAR OBJECTS; ACTIVE GALACTIC NUCLEI; RADIATIVE ACCELERATION; DISK WINDS; QSOS; PG-0946+301; OUTFLOWS; SPECTROGRAPH; ULTRAVIOLET AB We describe deep (40 orbits) Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph observations of the broad absorption line (BAL) quasi-stellar object (QSO) PG 0946+301 and make them available to the community. These observations are the major part of a multiwavelength campaign on this object aimed at determining the ionization equilibrium and abundances (IEAs) in BALQSOs. We present simple template fits to the entire data set, which yield firm identifications for more than two dozen BALs from 18 ions and give lower limits for the ionic column densities. We find that the outflow's metallicity is consistent with being solar, while the abundance ratio of phosphorus to other metals is at least 10 times solar. These findings are based on diagnostics that are not sensitive to saturation and partial covering effects in the BALs, which considerably weakened previous claims for enhanced metallicity. Ample evidence for these effects is seen in the spectrum. We also discuss several options for extracting tighter IEA constraints in future analyses and present the significant temporal changes that are detected between these spectra and those taken by the HST Faint Object Spectrograph in 1992. C1 Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Australian Natl Univ, Res Sch Astron & Astrophys, Canberra, ACT 2611, Australia. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. NASA, Astron & Solar Phys Lab, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Kitt Peak Natl Observ, Tucson, AZ 85726 USA. Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England. Univ Texas, Dept Astron, Austin, TX 78712 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 105, University Pk, PA 16802 USA. Smithsonian Astrophys Observ, Hilo, HI 96721 USA. Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. Univ Toronto, Canadian Inst Theoret Astrophys, Toronto, ON M5S 3H8, Canada. RP Arav, N (reprint author), Univ Calif Berkeley, Dept Astron, 601 Campbell Hall 3411, Berkeley, CA 94720 USA. RI Brandt, William/N-2844-2015 OI Brandt, William/0000-0002-0167-2453 NR 39 TC 71 Z9 72 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 2001 VL 561 IS 1 BP 118 EP 130 DI 10.1086/323369 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487PC UT WOS:000171883600012 ER PT J AU Jimenez, R Band, D Piran, T AF Jimenez, R Band, D Piran, T TI Energetics of gamma-ray bursts SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts ID HUBBLE-DEEP-FIELD; BROAD-BAND PHOTOMETRY; LUMINOSITY; EVOLUTION; REDSHIFTS; GALAXIES; SPACE AB We determine the distribution of total energy emitted by gamma-ray bursts for bursts with fluence and distance information. Our core sample consists of eight bursts with BATSE spectra and spectroscopic redshifts. We extend this sample by adding four bursts with BATSE spectra and host galaxy R magnitudes. From these R magnitudes, we calculate a redshift probability distribution; this method requires a model of the host galaxy population. From a sample of 10 bursts with both spectroscopic redshifts and host galaxy R magnitudes (some do not have BATSE spectra), we find that the burst rate is proportional to the galaxy luminosity at the epoch of the burst. Assuming that the total energy emitted has a lognormal distribution, we find that the average emitted energy (assumed to be radiated isotropically) is iso> = 1.3(-0.7)(+1.2) x 10(53) ergs (for km s(-1) Mpc(-1), Omega (m) = 0.3, and Omega (Lambda) = 0.7) the distribution has a logarithmic width of sigma (gamma) = 1.7(-0.3)(+0.7). The corresponding distribution of X-ray afterglow energy (for seven bursts) has = 3.5(-1.3)(+2.1) x 10(51) ergs and sigma (X) = 1.3(-0.3)(+0.4). For completeness, we also provide spectral fits for all bursts with BATSE spectra for which there were afterglow searches. C1 Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. RP Jimenez, R (reprint author), Rutgers State Univ, Dept Phys & Astron, 136 Frelinghuysen Rd, Piscataway, NJ 08854 USA. OI Jimenez, Raul/0000-0002-3370-3103 NR 19 TC 46 Z9 46 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 2001 VL 561 IS 1 BP 171 EP 177 DI 10.1086/323224 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487PC UT WOS:000171883600016 ER PT J AU Lee, BC Tucker, DL Vanden Berk, DE Yanny, B Reichart, DE Adelman, J Chen, B Harvanek, M Henden, A Ivezic, Z Kleinman, S Lamb, D Long, D McMillan, R Newman, PR Nitta, A Palunas, P Schneider, DP Snedden, S York, D Briggs, JW Brinkmann, J Csabai, I Hennessy, GS Kent, S Lupton, R Newberg, HJ Stoughton, C AF Lee, BC Tucker, DL Vanden Berk, DE Yanny, B Reichart, DE Adelman, J Chen, B Harvanek, M Henden, A Ivezic, Z Kleinman, S Lamb, D Long, D McMillan, R Newman, PR Nitta, A Palunas, P Schneider, DP Snedden, S York, D Briggs, JW Brinkmann, J Csabai, I Hennessy, GS Kent, S Lupton, R Newberg, HJ Stoughton, C TI Sloan Digital Sky Survey multicolor observations of GRB 010222 SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts ID GAMMA-RAY BURST; OPTICAL-EMISSION; ABSORPTION; AFTERGLOWS; RADIATION; CURVES; SEARCH AB The discovery of an optical counterpart to GRB 010222 (detected by BeppoSAX) was announced 4.4 hr after the burst by Henden. The Sloan Digital Sky Survey's 0.5 m photometric telescope (PT) and 2.5 m survey telescope were used to observe the afterglow of GRB 010222 starting 4.8 hr after the gamma-ray burst. The 0.5 m PT observed the afterglow in five 300 s g*-band exposures over the course of half an hour, measuring a temporal decay rate in this short period of F(v) proportional to t(-1.0 +/-0.5). The 2.5 m camera imaged the counterpart nearly simultaneously in five filters (u*, g*, r*, i*, z*), with r* = 18.74 +/- 0.02 at 12:10 UT. These multicolor observations, corrected for reddening and the afterglow's temporal decay, are well-fitted by the power law F(v) proportional to v(-0.90 +/-0.03) with the exception of the u*-band UV flux which is 20% below this slope. We examine possible interpretations of this spectral shape, including source extinction in a star-forming region. C1 Fermilab Natl Accelerator Lab, Expt Astrophys Lab, Batavia, IL 60510 USA. CALTECH, Palomar Observ, Pasadena, CA 91125 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. European Space Agcy, XMM Sci Operat Ctr, Madrid 28080, Spain. Apache Point Observ, Sunspot, NM 88349 USA. Univ Space Res Assoc, USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Catholic Univ Amer, NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Chicago, Yerkes Observ, Williams Bay, WI 53191 USA. Eotvos Lorand Univ, Dept Phys Complex Syst, H-1518 Budapest, Hungary. USN Observ, Washington, DC 20392 USA. Rensselaer Polytech Inst, Dept Phys, Troy, NY 12180 USA. RP Lee, BC (reprint author), Fermilab Natl Accelerator Lab, Expt Astrophys Lab, POB 500, Batavia, IL 60510 USA. EM bclee@fnal.gov; dtucker@fnal.gov; danvb@fnal.gov; yanny@fnal.gov; der@astro.caltech.edu; jen_a@fnal.gov; bchen@xmm.vilspa.esa.es; harvanek@aapo.nmsu.edu; aah@nofs.navy.mil; ivezic@astro.princeton.edu; sjk@apo.nmsu.edu; lamb@pion.uchicago.edu; long@apo.nmsu.edu; mcmillan@apo.nmsu.edu; prn@apo.nmsu.edu; ank@apo.nmsu.edu; palunas@etendue.gsfc.nasa.gov; dps@astro.psu.edu; snedden@apo.nmsu.edu; jwb@hale.yerkes.uchicago.edu; brinkmann@nmsu.edu; csabai@pha.jhu.edu; gsh@cygnus.usno.navy.mil; skent@fnal.gov; rhl@astro.princeton.edu; heidi@rpi.edu; stoughto@fnal.gov RI Csabai, Istvan/F-2455-2012; OI Csabai, Istvan/0000-0001-9232-9898 NR 42 TC 20 Z9 20 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 2001 VL 561 IS 1 BP 183 EP 188 DI 10.1086/322981 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487PC UT WOS:000171883600018 ER PT J AU Neuforge-Verheecke, C Guzik, JA Keady, JJ Magee, NH Bradley, PA Noels, A AF Neuforge-Verheecke, C Guzik, JA Keady, JJ Magee, NH Bradley, PA Noels, A TI Helioseismic tests of the new Los Alamos LEDCOP opacities SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic data; Sun : helioseismology; Sun : interior ID THERMONUCLEAR REACTION-RATES; SOLAR MODELS; NEUTRINO EXPERIMENTS; ELEMENT DIFFUSION; CROSS-SECTIONS; INFERENCES; OPAL AB We compare the helioseismic properties of two solar models, one calibrated with the OPAL opacities and the other with the recent Los Alamos LEDCOP (Light Element Detailed Configuration Opacity) opacities. We show that, in the radiative interior of the Sun, the small differences between the two sets of opacities (up to 6% near the base of the convection zone) lead to noticeable differences in the solar structure (up to 0.3% in sound speed), with the OPAL model being the closest to the helioseismic data. More than half of the difference between the two opacity sets results from the interpolation scheme and from the relatively widely spaced temperature grids used in the tables. The remaining 3% intrinsic difference between the OPAL and the LEDCOP opacities in the radiative interior of the Sun is well within the error bars on the opacity calculations resulting from the uncertainties on the physics. We conclude that both the OPAL and LEDCOP opacities produce solar models in close agreement with helioseismic inferences, but discrepancies still persist at the level of 0.6% between the calculated and inferred sound speed in the radiative interior of the Sun. C1 Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Liege, Inst Astrophys & Geophys, B-4000 Liege, Belgium. RP Neuforge-Verheecke, C (reprint author), Univ Liege, Inst Astrophys & Geophys, 5 Ave Cointe, B-4000 Liege, Belgium. NR 30 TC 27 Z9 27 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 2001 VL 561 IS 1 BP 450 EP 454 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487PC UT WOS:000171883600042 ER PT J AU da Silva, AC Kay, ST Liddle, AR Thomas, PA Pearce, FR Barbosa, D AF da Silva, AC Kay, ST Liddle, AR Thomas, PA Pearce, FR Barbosa, D TI Impact of cooling and preheating on the Sunyaev-Zeldovich effect SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; cosmology : theory; galaxies : clusters : general methods : numerical ID GALAXY CLUSTERS; SPECTRUM; HISTORY; HYDRA AB We use hydrodynamical simulations to assess the impact of radiative cooling and "preheating" on predictions for the Sunyaev-Zeldovich (SZ) effect. Cooling significantly reduces both the mean SZ signal and its angular power spectrum, while preheating can increase the mean distortion while leaving the angular power spectrum below that found in a simulation without heating or cooling. We study the relative contribution from high- and low-density gas, and we find that in the cooling model about 60% of the mean thermal distortion arises from low-overdensity gas. We find that halos dominate the thermal SZ power spectrum in all models, while in the cooling simulation the kinetic SZ power spectrum originates predominantly in lower overdensity gas. C1 Univ Sussex, Ctr Astron, Brighton BN1 9QJ, E Sussex, England. Univ Nottingham, Nottingham NG7 2RD, England. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. Inst Super Tecn, Ctr Multidisplinar Astrofis, Lisbon, Portugal. RP da Silva, AC (reprint author), Univ Sussex, Ctr Astron, Brighton BN1 9QJ, E Sussex, England. RI Pearce, Frazer/H-1503-2012; Da Silva, Antonio/A-2693-2010; OI Da Silva, Antonio/0000-0002-6385-1609; Pearce, Frazer/0000-0002-2383-9250; Barbosa, Domingos/0000-0002-5191-7826; Thomas, Peter/0000-0001-6888-6483 NR 28 TC 45 Z9 45 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 2001 VL 561 IS 1 BP L15 EP L18 DI 10.1086/324574 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487PD UT WOS:000171883700004 ER PT J AU Lee, AT Ade, P Balbi, A Bock, J Borrill, J Boscaleri, A de Bernardis, P Ferreira, PG Hanany, S Hristov, VV Jaffe, AH Mauskopf, PD Netterfield, CB Pascale, E Rabii, B Richards, PL Smoot, GF Stompor, R Winant, CD Wu, JHP AF Lee, AT Ade, P Balbi, A Bock, J Borrill, J Boscaleri, A de Bernardis, P Ferreira, PG Hanany, S Hristov, VV Jaffe, AH Mauskopf, PD Netterfield, CB Pascale, E Rabii, B Richards, PL Smoot, GF Stompor, R Winant, CD Wu, JHP TI A high spatial resolution analysis of the MAXIMA-1 cosmic microwave background anisotropy data SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; cosmology : observations ID RADIATION; UNIVERSE; FLAT AB We extend the analysis of the MAXIMA-1 cosmic microwave background data to smaller angular scales. MAXIMA, a bolometric balloon-borne experiment, mapped a 124 deg(2) region of the sky with 10' resolution at frequencies of 150, 240, and 410 GHz during its first flight. The original analysis, which covered the multipole range 36 less than or equal to l less than or equal to 785 using a 100 deg(2) map, is extended to l = 1235 using a subset of the data from three 150 GHz photometers in the fully cross-linked central 60 deg(2) of the map. The main improvement over the original analysis is the use of 3' square pixels in the calculation of the map. The new analysis is consistent with the original for l < 785. For l > 785, where inflationary models predict a third acoustic peak, the new analysis shows power with an amplitude of 56 +/- 7 muK at l similar or equal to 850 in excess to the average power of 42 +/- 3 muK in the range 441 < l < 785. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Univ London Queen Mary & Westfield Coll, London E1 4NS, England. Univ Roma Tor Vergata, Dipartimento Fis, I-00133 Rome, Italy. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. CNR, IROE, I-50127 Florence, Italy. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Univ Oxford, Dept Astrophys, Oxford OX1 3RH, England. Inst Super Tecn, CENTRA, P-1096 Lisbon, Portugal. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Univ Wales Coll Cardiff, Dept Phys & Astron, Cardiff CF2 3YB, S Glam, Wales. Univ Toronto, Dept Phys & Astron, Toronto, ON M5S 1A1, Canada. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Copernicus Astron Ctr, PL-00716 Warsaw, Poland. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. RP Lee, AT (reprint author), Univ Calif Berkeley, Dept Phys, 366 Le Conte Hall, Berkeley, CA 94720 USA. RI Jaffe, Andrew/D-3526-2009; OI de Bernardis, Paolo/0000-0001-6547-6446; WU, JIUN-HUEI/0000-0001-9608-7662 NR 19 TC 303 Z9 305 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 2001 VL 561 IS 1 BP L1 EP L5 DI 10.1086/324437 PN 2 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487PD UT WOS:000171883700001 ER PT J AU Sion, EM Cheng, FH Szkody, P Gansicke, B Sparks, WM Hubeny, I AF Sion, EM Cheng, FH Szkody, P Gansicke, B Sparks, WM Hubeny, I TI Hubble Space Telescope STIS spectroscopy of VW Hydri during early quiescence following a superoutburst SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; stars : abundances; stars : dwarf novae; stars : individual (VW Hydri); white dwarfs ID WHITE-DWARF; NOVA; ACCRETION; OUTBURST; MASS AB Hubble Space Telescope Space Telescope Imaging Spectrograph (STIS) observations of VW Hydri 2 and 7 days after the end of a superoutburst reveal a heated white dwarf with deep broad Ly alpha, narrow metallic absorption features and evidence of a hotter Keplerian-broadened component. We confirm the existence of enhanced abundances of odd-numbered nuclear species P, Mn, and Al as well as an N/C ratio indicative of CNO H-burning thermonuclear processing. Our best single-temperature white dwarf reduced chi (2) fit to the first spectrum reveals (1) a DAZQ white dwarf with T-eff = 22,500 +/- 500 K, log g = 8.0, and photospheric abundances C = 0.3 solar, N = 3.0 solar, O = 3.0 solar, Si = 0.3 solar, Al = 2 solar, Fe = 0.5 solar, Mg = 3.0 solar, Mn = 50 solar, Ni = 0.3 solar, P = 15 solar, and Ti = 0.1 solar. The best-fit white dwarf + accretion belt composite model yields a large improvement in the reduced chi (2) value. The accretion belt temperature is 32,000 K and covers a fractional area of 3%, contributing 11% of the flux. The second spectrum 5 days later reveals slightly increased metal abundances except that P is elevated to 20 times solar while Fe has declined to 0.05 times solar. The white dwarf has cooled by approximate to 1000 K, the belt temperature is 32,000 K, and the fractional area and flux contribution of the belt are 5% and 20%, respectively. These STIS observations confirm that a past (prehistoric?) thermonuclear runaway has occurred on the white dwarf in VW Hyi. It is expected that the thermonuclear runaway would be strong enough to produce a nova outburst. Therefore, these two classes of close binaries, namely, dwarf novae and classical novae, are linked and can overlap. C1 Villanova Univ, Dept Astron & Astrophys, Villanova, PA 19085 USA. Univ Sci & Technol China, Ctr Astrophys, Hefei 230026, Anhui, Peoples R China. Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Univ Gottingen, D-37083 Gottingen, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Sion, EM (reprint author), Villanova Univ, Dept Astron & Astrophys, Villanova, PA 19085 USA. RI Gaensicke, Boris/A-9421-2012 OI Gaensicke, Boris/0000-0002-2761-3005 NR 15 TC 19 Z9 19 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 2001 VL 561 IS 1 BP L127 EP L130 DI 10.1086/324558 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487PD UT WOS:000171883700030 ER PT J AU Stompor, R Abroe, M Ade, P Balbi, A Barbosa, D Bock, J Borrill, J Boscaleri, A de Bernardis, P Ferreira, PG Hanany, S Hristov, V Jaffe, AH Lee, AT Pascale, E Rabii, B Richards, PL Smoot, GF Winant, CD Wu, JHP AF Stompor, R Abroe, M Ade, P Balbi, A Barbosa, D Bock, J Borrill, J Boscaleri, A de Bernardis, P Ferreira, PG Hanany, S Hristov, V Jaffe, AH Lee, AT Pascale, E Rabii, B Richards, PL Smoot, GF Winant, CD Wu, JHP TI Cosmological implications of the MAXIMA-1 high-resolution cosmic microwave background anisotropy measurement SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; cosmology : observations ID POWER SPECTRUM; UNIVERSE; CONSTANT; CONSTRAINTS; SUPERNOVAE; BOOMERANG AB We discuss the cosmological implications of the new constraints on the power spectrum of the cosmic microwave background (CMB) anisotropy derived from a new high-resolution analysis of the MAXIMA-1 measurement. The power spectrum indicates excess power at l similar to 860 over the average level of power at 411 less than or equal to l less than or equal to 785. This excess is statistically significant at the similar to 95% confidence level. Its position coincides with that of the third acoustic peak, as predicted by generic inflationary models selected to fit the first acoustic peak as observed in the data. The height of the excess power agrees with the predictions of a family of inflationary models with cosmological parameters that are fixed to fit the CMB data previously provided by BOOMERANG-LDB and MAXIMA-1 experiments. Our results therefore lend support for inflationary models and more generally for the dominance of adiabatic coherent perturbations in the structure formation of the universe. At the same time, they seem to disfavor a large variety of the nonstandard (but inflation-based) models that have been proposed to improve the quality of fits to the CMB data and the consistency with other cosmological observables. Within standard inflationary models, our results combined with the COBE/Differential Microwave Radiometer data give best-fit values and 95% confidence limits for the baryon density, Omega (b)h(2) similar or equal to 0.033 +/- 0.013, and the total density, Omega = 0.9(-0.16)(+0.18). The primordial spectrum slope (n(s)) and the optical depth to the last scattering surface (tau (c)) are found to be degenerate and to obey the relation n(s) similar or equal to (0.99 +/- 0.14) + 0.46 tau (c), for tau (c) less than or equal to 0.5 (all at 95% confidence levels). C1 Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Copernicus Astron Ctr, PL-00716 Warsaw, Poland. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Queen Mary Univ London, London E1 4NS, England. Univ Roma Tor Vergata, Dipartimento Fis, I-00133 Rome, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys, Berkeley, CA 94720 USA. Inst Super Tecn, CENTRA, P-1096 Lisbon, Portugal. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. CNR, IROE, I-50127 Florence, Italy. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Univ Oxford, Dept Astrophys, Oxford OX1 3RH, England. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Ctr Particle Astrophys, 301 Le Conte Hall, Berkeley, CA 94720 USA. RI Jaffe, Andrew/D-3526-2009; OI de Bernardis, Paolo/0000-0001-6547-6446; WU, JIUN-HUEI/0000-0001-9608-7662; Barbosa, Domingos/0000-0002-5191-7826 NR 30 TC 204 Z9 205 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD NOV 1 PY 2001 VL 561 IS 1 BP L7 EP L10 DI 10.1086/324438 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 487PD UT WOS:000171883700002 ER PT J AU Prochaska, JX Wolfe, AM Tytler, D Burles, S Cook, J Gawiser, E Kirkman, D O'Meara, JM Storrie-Lombardi, L AF Prochaska, JX Wolfe, AM Tytler, D Burles, S Cook, J Gawiser, E Kirkman, D O'Meara, JM Storrie-Lombardi, L TI The UCSD HIRES/Keck I damped Ly alpha abundance database. I. The data SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE galaxies : abundances; galaxies : evolution; nuclear reactions, nucleosynthesis, abundances; quasars : absorption lines ID ABSORPTION F-VALUES; OSCILLATOR-STRENGTHS; LYMAN-ALPHA; METAL ABUNDANCES; HIGH REDSHIFTS; ATOMIC DATA; CHEMICAL ABUNDANCES; UVES OBSERVATIONS; DISK GALAXIES; SYSTEMS AB We present new chemical abundance measurements of 16 damped Ly alpha systems at z > 1.5 and update our previous abundance analyses. The entire database presented here was derived from HIRES observations on the Keck I telescope, reduced with the same software package, and analyzed with identical techniques. Altogether, we present a large, homogeneous database of chemical abundance measurements for protogalaxies in the early universe, ideal for studying a number of important aspects of galaxy formation. In addition, we have established an on-line directory for this database and will continuously update the results. C1 Carnegie Inst Washington Observ, Pasadena, CA 91101 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif San Diego, Ctr Astrophys & Space Sci, La Jolla, CA 92093 USA. Fermilab Natl Accelerator Lab, Expt Astrophys Dept, Chicago, IL 60637 USA. CALTECH, SIRTF Sci Ctr, Pasadena, CA 91125 USA. RP Prochaska, JX (reprint author), Carnegie Inst Washington Observ, 813 Santa Barbara St, Pasadena, CA 91101 USA. NR 49 TC 109 Z9 109 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD NOV PY 2001 VL 137 IS 1 BP 21 EP 73 DI 10.1086/322542 PG 53 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 492CL UT WOS:000172149800002 ER PT J AU Lindberg, S Landis, MS Stevens, RK Brooks, S AF Lindberg, S Landis, MS Stevens, RK Brooks, S TI Comments on "Atmospheric mercury species in the European Arctic: measurements and modeling" by Berg et al. Atmospheric Environment 14 (2001), 2569-2582 SO ATMOSPHERIC ENVIRONMENT LA English DT Editorial Material ID GASEOUS MERCURY; AMBIENT AIR; SPECIATION C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. US EPA, Natl Exposure Res Lab, Washington, DC 20460 USA. RP Lindberg, S (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Landis, Matthew/P-5149-2014 OI Landis, Matthew/0000-0002-8742-496X NR 8 TC 14 Z9 14 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD NOV PY 2001 VL 35 IS 31 BP 5377 EP 5378 DI 10.1016/S1352-2310(01)00310-7 PG 2 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 488BC UT WOS:000171913300015 ER PT J AU Howse, JW Ticknor, LO Muske, KR AF Howse, JW Ticknor, LO Muske, KR TI Least squares estimation techniques for position tracking of radioactive sources SO AUTOMATICA LA English DT Article DE state estimation; estimation algorithms; maximum likelihood estimators AB This paper describes least squares estimation algorithms used for tracking the physical location of radioactive sources in real time as they are moved around in a facility. We present both recursive and moving horizon nonlinear least squares estimation algorithms that consider both the change in the source location and the deviation between measurements and model predictions. The measurements used to estimate position consist of four count rates reported by four different gamma ray detectors. There is an uncertainty in the source location due to the large variance of the detected count rate, and the uncertainty in the background count rate. This work represents part of a suite of tools which will partially automate security and safety assessments, allow some assessments to be done remotely, and provide additional sensor modalities with which to make assessments. Published by Elsevier Science Ltd. C1 Los Alamos Natl Lab, Modeling Algorithms & Informat Grp, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Stat Grp, Los Alamos, NM 87545 USA. Villanova Univ, Dept Chem Engn, Villanova, PA 19085 USA. RP Howse, JW (reprint author), Los Alamos Natl Lab, Modeling Algorithms & Informat Grp, CCS-3,Mail Stop B265, Los Alamos, NM 87545 USA. NR 18 TC 26 Z9 26 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0005-1098 J9 AUTOMATICA JI Automatica PD NOV PY 2001 VL 37 IS 11 BP 1727 EP 1737 DI 10.1016/S0005-1098(01)00134-0 PG 11 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA 476VQ UT WOS:000171249800004 ER PT J AU Majewski, J Kuhl, TL Kjaer, K Smith, GS AF Majewski, J Kuhl, TL Kjaer, K Smith, GS TI Packing of ganglioside-phospholipid monolayers: An X-ray diffraction and reflectivity study SO BIOPHYSICAL JOURNAL LA English DT Article ID GRAZING-INCIDENCE DIFFRACTION; MYELIN BASIC-PROTEIN; CHOLERA-TOXIN; LIPID MONOLAYERS; PHASE-BEHAVIOR; CELL-MEMBRANES; GM1; BILAYERS; SURFACE; DIFFERENCE AB Using synchrotron grazing-incidence x-ray diffraction (GIXD) and reflectivity, the in-plane and out-of-plane structure of mixed ganglioside-phospholipid monolayers was investigated at the air-water interface. Mixed monolayers of 0, 5, 10, 20, and 100 mol% ganglioside GM, and the phospholipid dipaimitoylphosphatidylethanolamine (DPPE) were studied in the solid phase at 23 degreesC and a surface pressure of 45 mN/m. At these concentrations and conditions the two components do not phase-separate and no evidence for domain formation was observed. X-ray scattering measurements reveal that GM, is accommodated within the host DPPE monolayer and does not distort the hexagonal in-plane unit cell or out-of-plane two-dimensional (2-D) packing compared with a pure DPPE monolayer. The oligosaccharide headgroups were found to extend normally from the monolayer surface, and the incorporation of these glycolipids into DPPE monolayers did not affect hydrocarbon tail packing (fluidization or condensation of the hydrocarbon region). This is in contrast to previous investigations of lipopolymer-lipid mixtures, where the packing structure of phospholipid monolayers was greatly altered by the inclusion of lipids bearing hydrophilic polymer groups. Indeed, the lack of packing disruptions by the oligosaccharide groups indicates that protein-GM, interactions, including binding, insertion, chain fluidization, and domain formation (lipid rafts), can be studied in 2-D monolayers using scattering techniques. C1 Univ Calif Davis, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. Riso Natl Lab, Dept Solid State Phys, DK-4000 Roskilde, Denmark. RP Kuhl, TL (reprint author), Univ Calif Davis, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. EM tlkuhl@ucdavis.edu RI Lujan Center, LANL/G-4896-2012 NR 37 TC 63 Z9 64 U1 0 U2 11 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD NOV PY 2001 VL 81 IS 5 BP 2707 EP 2715 PG 9 WC Biophysics SC Biophysics GA 485LE UT WOS:000171755200024 PM 11606283 ER PT J AU Last, JA Waggoner, TA Sasaki, DY AF Last, JA Waggoner, TA Sasaki, DY TI Lipid membrane reorganization induced by chemical recognition SO BIOPHYSICAL JOURNAL LA English DT Article ID ATOMIC-FORCE MICROSCOPY; PHOSPHOLIPID-BILAYERS; OPTICAL-DETECTION; VESICLES; ION; RECEPTORS; ADHESION; BINDING; SURFACE AB Nanoscale structural reorganization of a lipid bilayer membrane induced by a chemical recognition event has been imaged using in situ atomic force microscopy (AFM). Supported lipid bilayers, composed of distearylphosphatidylcholine (DSPC) and a synthetic lipid functionalized with a Cu(2+) receptor, phase-separate into nanoscale domains that are distinguishable by the 9 Angstrom height difference between the two molecules. Upon binding of Cu(2+) the electrostatic nature of the receptor changes, causing a dispersion of the receptor molecules and subsequent shrinking of the structural features defined by the receptors in the membrane. Complete reversibility of the process was demonstrated through the removal of metal ions with EDTA. C1 Sandia Natl Labs, Biomol Mat & Interfaces Dept, Albuquerque, NM 87185 USA. RP Sasaki, DY (reprint author), Sandia Natl Labs, Biomol Mat & Interfaces Dept, MS 1413, Albuquerque, NM 87185 USA. EM dysasak@sandia.gov NR 25 TC 21 Z9 22 U1 0 U2 1 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD NOV PY 2001 VL 81 IS 5 BP 2737 EP 2742 PG 6 WC Biophysics SC Biophysics GA 485LE UT WOS:000171755200027 PM 11606286 ER PT J AU Foreman, TM Khalil, M Meier, P Brainard, JR Vanderberg, LA Sauer, NN AF Foreman, TM Khalil, M Meier, P Brainard, JR Vanderberg, LA Sauer, NN TI Effects of charged water-soluble polymers on the stability and activity of yeast alcohol dehydrogenase and subtilisin Carlsberg SO BIOTECHNOLOGY AND BIOENGINEERING LA English DT Article DE subtilisin; alcohol Dehydrogenase; water-soluble polymers; stabilization; activity; interactions; poly(acrylic acid); polyethylenimine ID POLY(DIMETHYLDIALLYLAMMONIUM CHLORIDE); THERMAL-STABILITY; GLUCOSE-DEHYDROGENASE; STABILIZATION; PROTEINS; THERMOSTABILIZATION; POLYETHYLENEIMINE; IMMOBILIZATION; COMPLEXATION; ADDITIVES AB Remarkable increases in enzyme catalytic stability resulting from addition of charged water-soluble polymers have recently been reported, suggesting that use of these polymers may be an attractive general strategy for enzyme stabilization. To test the proposed hypothesis that coulombic forces between water-soluble polymers and enzymes are primarily responsible for enzyme stabilization, we examined the catalytic stability and activity of two enzymes in the presence of polymers differing in net charge. All polymers tested increased enzyme lifetimes, regardless of their net charge, suggesting that stabilization of these enzymes by water-soluble polymers is not solely dependent on simple electrostatic interactions between the polymers and enzymes. (C) 2001 John Wiley & Sons, Inc. C1 Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. RP Brainard, JR (reprint author), POB 1663,Mail Stop M888, Los Alamos, NM 87545 USA. NR 35 TC 11 Z9 13 U1 0 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0006-3592 J9 BIOTECHNOL BIOENG JI Biotechnol. Bioeng. PD NOV PY 2001 VL 76 IS 3 BP 241 EP 246 DI 10.1002/bit.1187 PG 6 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 487CH UT WOS:000171855700009 PM 11668460 ER PT J AU Noguchi, CT Gladwin, M Diwan, B Merciris, P Smith, R Yu, XB Buzard, G Fitzhugh, A Keefer, LK Schechter, AN Mohandas, N AF Noguchi, CT Gladwin, M Diwan, B Merciris, P Smith, R Yu, XB Buzard, G Fitzhugh, A Keefer, LK Schechter, AN Mohandas, N TI Pathophysiology of a sickle cell trait mouse model: Human alpha beta(S) transgenes with one mouse beta-globin allele SO BLOOD CELLS MOLECULES AND DISEASES LA English DT Article DE sickle cell trait; pathophysiology; transgenic mouse; kidney pathology; oxygen affinity ID RENAL MEDULLARY CARCINOMA; THALASSEMIC MICE; HEMOGLOBIN; DISEASE; POLYMERIZATION; ABNORMALITIES; NEPHROPATHY AB As a potential model for sickle cell trait (AS), we examined mice containing one normal mouse beta-globin allele in combination with a human hemoglobin S (halphabeta(S)) transgene (mbeta/hS). The mice segregated into two subpopulations containing low and high proportions of hemoglobin S (mbeta/hS1 and mbeta/hS2, respectively) that was associated with one or two human halphabeta(S) transgenes. We noted striking kidney pathology (cortical cysts, hyperplastic tubules, and glomerulonephritis), increasing with age and with greater severity in mbeta/hS1. mbeta/hS2 animals were largely tolerant to 5% O-2 for 1 h, whereas 80% of mbeta/hS1 mice died, exhibiting acute sequestration of erythrocytes in spleen, liver, and heart. These pathologies appear to result from a decreased oxygen affinity of the hybrid (human alpha/mouse beta) hemoglobins with a mild beta-thalassemia phenotype. Thus, these mouse models of sickle trait seem to manifest their renal pathology and sensitivity to hypoxia by mechanisms related to low tissue oxygen delivery and are different from the human syndrome. Analyses of parameters such as P-50, red cell indices, and genetic background are necessary in establishing potential relevance of any mouse model of the sickle cell syndromes. C1 NIDDK, Biol Chem Lab, NIH, Bethesda, MD 20892 USA. NIH, Dept Crit Care Med, CC, Bethesda, MD 20892 USA. NCI, Intramural Res Support Program, SAIC, Frederick, MD 21702 USA. NCI, Comparat Carcinogenesis Lab, Frederick, MD 21702 USA. Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Noguchi, CT (reprint author), NIDDK, Biol Chem Lab, NIH, Bethesda, MD 20892 USA. RI Keefer, Larry/N-3247-2014; OI Keefer, Larry/0000-0001-7489-9555; Schechter, Alan N/0000-0002-5235-9408 FU NCI NIH HHS [N01-CO-56000]; NHLBI NIH HHS [HL31579] NR 25 TC 17 Z9 17 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1079-9796 J9 BLOOD CELL MOL DIS JI Blood Cells Mol. Dis. PD NOV-DEC PY 2001 VL 27 IS 6 BP 971 EP 977 DI 10.1006/bcmd.2001.0469 PG 7 WC Hematology SC Hematology GA 523VD UT WOS:000173977200002 PM 11831863 ER PT J AU Glimm, J Jin, H AF Glimm, J Jin, H TI An asymptotic analysis of two-phase fluid mixing SO BOLETIM DA SOCIEDADE BRASILEIRA DE MATEMATICA LA English DT Article DE multiphase flow; asymptotic expansions; incompressible two phase fluids ID 2-PHASE FLOW MODEL; RAYLEIGH-TAYLOR; COMPRESSIBLE FLUIDS AB We study the motion of the slightly compressible multi-phase flow model proposed by Chen, Glimm, Sharp and Zhang. The interface velocity and constitutive law are analyzed by derivation of the exact quantity. Using singular perturbation theory, a formal asymptotic expansion is derived for the solution of the compressible equations. An asymptotic analysis in the incompressible limit, for slightly compressible flows supplies important new information to resolve nonuniqueness of the pressure difference between the two fluid species of the incompressible flow equations. C1 SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Ctr Data Intens Comp, Upton, NY 11793 USA. RP Glimm, J (reprint author), SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. NR 16 TC 11 Z9 12 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0100-3569 J9 BOL SOC BRAS MAT JI Bol. Soc. Bras. Mat. PD NOV PY 2001 VL 32 IS 3 BP 213 EP 236 DI 10.1007/BF01233666 PG 24 WC Mathematics SC Mathematics GA 540CZ UT WOS:000174912100001 ER PT J AU Yusim, K Parnas, H Segel, LA AF Yusim, K Parnas, H Segel, LA TI One-vesicle hypothesis for neurotransmitter release: a possible molecular mechanism SO BULLETIN OF MATHEMATICAL BIOLOGY LA English DT Article ID VOLTAGE-DEPENDENT INTERACTION; CENTRAL SYNAPSES; PROTEINS; AUTORECEPTORS; TRANSMISSION; INHIBITION; DIFFUSION; MACHINERY; KINETICS AB Neurotransmitter-containing vesicles are clustered in release sites. Although a given site can contain tens of vesicles, there is evidence that under a wide range of conditions, following an action potential, rarely is more than one vesicle released from each site. Such findings led to the one vesicle hypothesis, for which this paper suggests a molecular mechanism. The release of a vesicle from a site provides a transient high concentration of transmitter in that site. It is proposed here that the local high transmitter concentration interrupts further vesicle releases from the same release site. The suggested mechanism for this 'release interruption' is based an a theory of release control by the authors wherein inhibitory transmitter autoreceptors play a central role. (That transmitter binding to these autoreceptors can inhibit release on a fast time scale has recently been shown experimentally.) A detailed kinetic scheme is presented for the proposed mechanism. Stochastic simulations of this scheme demonstrate how the mechanism accounts for the one vesicle hypothesis. In agreement with recent experiments, the simulations also show that changes in conditions that affect the release process can cause frequent release of more than one vesicle per site. (C) 2001 Society for Mathematical Biology. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Hebrew Univ Jerusalem, Inst Life Sci, Dept Neurobiol, IL-91904 Jerusalem, Israel. Weizmann Inst Sci, Dept Appl Math & Comp Sci, IL-76100 Rehovot, Israel. RP Los Alamos Natl Lab, MS K710,T-10, Los Alamos, NM 87545 USA. EM karina@t10.lanl.gov; hanna@vms.huji.ac.il; lee@wisdom.weizmann.ac.il NR 24 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0092-8240 EI 1522-9602 J9 B MATH BIOL JI Bull. Math. Biol. PD NOV PY 2001 VL 63 IS 6 BP 1025 EP 1040 DI 10.1006/bulm.2001.0247 PG 16 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA 492WP UT WOS:000172190800002 PM 11732174 ER PT J AU Oliveira, JS Bailey, CG Jones-Oliveira, JB Dixon, DA AF Oliveira, JS Bailey, CG Jones-Oliveira, JB Dixon, DA TI An algebraic-combinatorial model for the identification and mapping of biochemical pathways SO BULLETIN OF MATHEMATICAL BIOLOGY LA English DT Article ID CHEMICAL-EQUATIONS; REACTION SYSTEMS; THERMODYNAMICS; NETWORKS AB We develop the mathematical machinery for the construction of an algebraic-combinatorial model using Petri nets to construct an oriented matroid representation of biochemical pathways. For demonstration purposes, we use a model metabolic pathway example from the literature to derive a general biochemical reaction network model. The biomolecular networks define a connectivity matrix that identifies a linear representation of a Petri net. The sub-circuits that span a reaction network are subject to flux conservation laws. The conservation laws correspond to algebraic-combinatorial dual invariants, that are called S- (state) and T- (transition) invariants. Each invariant has an associated minimum support. We show that every minimum support of a Petri net invariant defines a unique signed sub-circuit representation. We prove that the family of signed sub-circuits has an implicit order that defines an oriented matroid. The oriented matroid is then used to identify the feasible sub-circuit pathways that span the biochemical network as the positive cycles in a hyper-digraph. (C) 2001 Society for Mathematical Biology. C1 Pacific NW Natl Lab, Modeling & Simulat Grp, Environm Mol Sci Lab, Richland, WA 99352 USA. Victoria Univ Wellington, Sch Comp Studies & Math, Wellington, New Zealand. RP Oliveira, JS (reprint author), Pacific NW Natl Lab, Modeling & Simulat Grp, Environm Mol Sci Lab, Richland, WA 99352 USA. NR 36 TC 22 Z9 22 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0092-8240 J9 B MATH BIOL JI Bull. Math. Biol. PD NOV PY 2001 VL 63 IS 6 BP 1163 EP 1196 DI 10.1006/bulm.2001.0263 PG 34 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA 492WP UT WOS:000172190800008 PM 11732180 ER PT J AU Blackmon, M Boville, B Bryan, F Dickinson, R Gent, P Kiehl, J Moritz, R Randall, D Shukla, J Solomon, S Bonan, G Doney, S Fung, I Hack, J Hunke, E Hurrell, J Kutzbach, J Meehl, J Otto-Bliesner, B Saravanan, R Schneider, EK Sloan, L Spall, M Taylor, K Tribbia, J Washington, W AF Blackmon, M Boville, B Bryan, F Dickinson, R Gent, P Kiehl, J Moritz, R Randall, D Shukla, J Solomon, S Bonan, G Doney, S Fung, I Hack, J Hunke, E Hurrell, J Kutzbach, J Meehl, J Otto-Bliesner, B Saravanan, R Schneider, EK Sloan, L Spall, M Taylor, K Tribbia, J Washington, W TI The Community Climate System Model SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID OCEAN CIRCULATION MODELS; SEA-ICE DYNAMICS; SHORTWAVE ABSORPTION; ATMOSPHERIC MODEL; DOWNWARD CONTROL; NATIONAL CENTER; VERSION 3; SIMULATIONS; SURFACE; FLUXES AB The Community Climate System Model (CCSM) has been created to represent the principal components of the climate system and their interactions. Development and applications of the model are carried out by the U.S. climate research community, thus taking advantage of both wide intellectual participation and computing capabilities beyond those available to most individual U.S. institutions. This article outlines the history of the CCSM, its current capabilities, and plans for its future development and applications, with the goal of providing a summary useful to present and future users. The initial version of the CCSM included atmosphere and ocean general circulation models, a land surface model that was grafted onto the atmosphere model, a sea-ice model, and a "flux coupler" that facilitates information exchanges among the component models with their differing grids. This version of the model produced a successful 300-yr simulation of the current climate without artificial flux adjustments. The model was then used to perform a coupled simulation in which the atmospheric CO2 concentration increased by 1% per year. In this version of the coupled model, the ocean salinity and deep-ocean temperature slowly drifted away from observed values, A subsequent correction to the roughness length used for sea ice significantly reduced these errors. An updated version of the CCSM was used to perform three simulations of the twentieth century's climate, and several projections of the climate of the twenty-first century, The CCSM's simulation of the tropical ocean circulation has been significantly improved by reducing the background vertical diffusivity and incorporating an anisotropic horizontal viscosity tensor. The meridional resolution of the ocean model was also refined near the equator. These changes have resulted in a greatly improved simulation of both the Pacific equatorial undercurrent and the surface countercurrents. The interannual variability of the sea surface temperature in the central and eastern tropical Pacific is also more realistic in simulations with the updated model. Scientific challenges to be addressed with future versions of the CCSM include realistic simulation of the whole atmosphere, including the middle and upper atmosphere, as well as the troposphere, simulation of changes in the chemical composition of the atmosphere through the incorporation of an integrated chemistry model; inclusion of global, prognostic biogeochemical components for land, ocean, and atmosphere; simulations of past climates, including times of extensive continental glaciation as well as times with little or no ice; studies of natural climate variability on seasonal-to-centennial timescales; and investigations of anthropogenic climate change. In order to make such studies possible, work is under way to improve all components of the model. Plans call for a new version of the CCSM to be released in 2002. Planned studies with the CCSM will require much more computer power than is currently available. C1 Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Ctr Ocean Land Atmosphere Studies, Calverton, MD USA. Univ Wisconsin, Madison, WI USA. Los Alamos Natl Lab, Los Alamos, NM USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. NOAA, Boulder, CO USA. George Mason Univ, Fairfax, VA 22030 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Univ Washington, Seattle, WA 98195 USA. Georgia Inst Technol, Atlanta, GA 30332 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Blackmon, M (reprint author), Natl Ctr Atmospher Res, POB 3000, Boulder, CO 80307 USA. EM blackmon@ncar.ucar.edu RI Doney, Scott/F-9247-2010; C, Y/G-5456-2010; Saravanan, Ramalingam/G-8879-2012; Taylor, Karl/F-7290-2011; Randall, David/E-6113-2011; Bryan, Frank/I-1309-2016; OI Doney, Scott/0000-0002-3683-2437; Saravanan, Ramalingam/0000-0002-0005-6907; Taylor, Karl/0000-0002-6491-2135; Randall, David/0000-0001-6935-4112; Bryan, Frank/0000-0003-1672-8330; Spall, Michael/0000-0003-1966-3122 NR 71 TC 90 Z9 101 U1 1 U2 8 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD NOV PY 2001 VL 82 IS 11 BP 2357 EP 2376 DI 10.1175/1520-0477(2001)082<2357:TCCSM>2.3.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 488HG UT WOS:000171929700001 ER PT J AU Baldocchi, D Falge, E Gu, LH Olson, R Hollinger, D Running, S Anthoni, P Bernhofer, C Davis, K Evans, R Fuentes, J Goldstein, A Katul, G Law, B Lee, XH Malhi, Y Meyers, T Munger, W Oechel, W U, KTP Pilegaard, K Schmid, HP Valentini, R Verma, S Vesala, T Wilson, K Wofsy, S AF Baldocchi, D Falge, E Gu, LH Olson, R Hollinger, D Running, S Anthoni, P Bernhofer, C Davis, K Evans, R Fuentes, J Goldstein, A Katul, G Law, B Lee, XH Malhi, Y Meyers, T Munger, W Oechel, W U, KTP Pilegaard, K Schmid, HP Valentini, R Verma, S Vesala, T Wilson, K Wofsy, S TI FLUXNET: A new tool to study the temporal and spatial variability of ecosystem-scale carbon dioxide, water vapor, and energy flux densities SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Review ID TEMPERATE DECIDUOUS FOREST; FREQUENCY-RESPONSE CORRECTIONS; LONG-TERM MEASUREMENTS; SURFACE-AIR EXCHANGE; SENSIBLE HEAT FLUXES; BOREAL ASPEN FOREST; LEAF-AREA INDEX; ATMOSPHERIC CO2; TERRESTRIAL ECOSYSTEMS; TALL VEGETATION AB FLUXNET is a global network of micrometeorological flux measurement site's that measure the exchanges of carbon dioxide, water vapor, and energy between the biosphere and atmosphere. At present over 140 sites are operating on a long-term and continuous basis. Vegetation under study includes temperate conifer and broadleaved (deciduous and evergreen) forests, tropical and boreal forests, crops, grasslands, chaparral, wetlands, and tundra. Sites exist on five continents and their latitudinal distribution ranges from 70 degreesN to 30 degreesS. FLUXNET has several primary functions. First, it provides infrastructure for compiling, archiving, and distributing carbon, water, and energy flux measurement, and meteorological, plant, and soil data to the science community. (Data and site information are available online at the FLUXNET Web site, http://www-eosdis.oml.gov/FLUXNTET/.) Second, the project supports calibration and flux intercomparison activities. This activity ensures that data from the regional networks are intercomparable. And third, FLUXNET supports the synthesis, discussion, and communication of ideas and data by supporting project scientists, workshops, and visiting scientists. The overarching goal is to provide information for validating computations of net primary productivity, evaporation, and energy absorption that are being generated by sensors mounted on the NASA Terra satellite. Data being compiled by FLUXNET are being used to quantify and compare magnitudes and dynamics of annual ecosystem carbon and water balances, to quantify the response of stand-scale carbon dioxide and water vapor flux densities to controlling biotic and abiotic factors, and to validate a hierarchy of soil-plant-atmosphere trace gas exchange models. Findings so far include 1) net CO2 exchange of temperate broadleaved forests increases by about 5.7 a C m(-2) day(-1) for each additional day that the growing season is extended; 2) the sensitivity of net ecosystem CO2 exchange to sunlight doubles if the sky is cloudy rather than clear; 3) the spectrum of CO2 flux density exhibits peaks at timescales of days, weeks, and years, and a spectral gap exists at the month timescale. 4) the optimal temperature of net CO2 exchange varies with mean summer temperature; and 5) stand age affects carbon dioxide and water vapor flux densities. C1 Univ Calif Berkeley, Dept Environm Sci Policy & Management, Ecosyst Sci Div, ESPM, Berkeley, CA 94720 USA. Univ Bayreuth, Bayreuth, Germany. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. US Forest Serv, USDA, Durham, NH USA. Univ Montana, Sch Forestry, Missoula, MT 59812 USA. Oregon State Univ, Corvallis, OR 97331 USA. Tech Univ Dresden, IHM Meteorol, Tharandt, Germany. Penn State Univ, Dept Meteorol, University Pk, PA USA. Univ Virginia, Dept Environm Sci, Charlottesville, VA 22903 USA. Duke Univ, Sch Environm, Durham, NC USA. Yale Univ, Sch Forestry, New Haven, CT USA. Univ Edinburgh, Inst Ecol & Resource Management, Edinburgh, Midlothian, Scotland. NOAA, Atmospher Turbulence & Diffus Div, Oak Ridge, TN USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. San Diego State Univ, Dept Biol, San Diego, CA 92182 USA. Univ Calif Davis, Davis, CA 95616 USA. Risoe Natl Lab, Plant Biol & Biogeochem Dept, Roskilde, Denmark. Indiana Univ, Dept Geog, Bloomington, IN 47405 USA. Univ Tuscia, DISAFRI, Viterbo, Italy. Univ Nebraska, Sch Nat Resource Sci, Lincoln, NE USA. Univ Helsinki, Dept Phys, Helsinki, Finland. RP Baldocchi, D (reprint author), Univ Calif Berkeley, Dept Environm Sci Policy & Management, Ecosyst Sci Div, ESPM, 151 Hilgard Hall, Berkeley, CA 94720 USA. RI Katul, Gabriel/A-7210-2008; Baldocchi, Dennis/A-1625-2009; Oechel, Walter/F-9361-2010; Munger, J/H-4502-2013; Gu, Lianhong/H-8241-2014; Vesala, Timo/C-3795-2017; Goldstein, Allen/A-6857-2011; Valentini, Riccardo/D-1226-2010; Hollinger, David/G-7185-2012; Schmid, Hans Peter/I-1224-2012; Pilegaard, Kim/I-7137-2013; Meyers, Tilden/C-6633-2016; Vuichard, Nicolas/A-6629-2011; OI Katul, Gabriel/0000-0001-9768-3693; Baldocchi, Dennis/0000-0003-3496-4919; Oechel, Walter/0000-0002-3504-026X; Munger, J/0000-0002-1042-8452; Gu, Lianhong/0000-0001-5756-8738; Vesala, Timo/0000-0002-4852-7464; Goldstein, Allen/0000-0003-4014-4896; Valentini, Riccardo/0000-0002-6756-5634; Schmid, Hans Peter/0000-0001-9076-4466; Pilegaard, Kim/0000-0002-5169-5717; Law, Beverly/0000-0002-1605-1203 NR 103 TC 1623 Z9 1769 U1 53 U2 455 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD NOV PY 2001 VL 82 IS 11 BP 2415 EP 2434 DI 10.1175/1520-0477(2001)082<2415:FANTTS>2.3.CO;2 PG 20 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 488HG UT WOS:000171929700004 ER PT J AU Enjalran, M Scalettar, RT Kauzlarich, SM AF Enjalran, M Scalettar, RT Kauzlarich, SM TI Geometric frustration in the mixed layer pnictide oxides SO CANADIAN JOURNAL OF PHYSICS LA English DT Article ID NEUTRON-DIFFRACTION; TRANSITIONS; COMPOUND; MODELS; PHASE; SB AB We present results from a Monte Carlo investigation of a simple bilayer model with geometrically frustrated interactions similar to those found in the mixed layer pnictide oxides (Sr(2)Mn(3)Pn(2)O(2), Pn = As, Sb). Our model is composed of two inequivalent square lattices with nearest-neighbor intralayer and interlayer interactions. We find a ground state composed of two independent Neel-ordered layers when the interlayer exchange is an order of magnitude weaker than the intralayer exchange, as suggested by experiment. We observe this result independent of the number of layers in our model. We find evidence for local orthogonal order between the layers, but it occurs in regions of parameter space that are not experimentally realized. We conclude that frustration caused by nearest-neighbor interactions in the mixed layer pnictide oxides is not sufficient to explain the long-range orthogonal order that is observed experimentally, and that it is likely that other terms (e.g., local anisotropies) in the Hamiltonian are required to explain the magnetic behavior. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. RP Enjalran, M (reprint author), Univ Waterloo, Dept Phys, Waterloo, ON N2L 3G1, Canada. NR 24 TC 1 Z9 1 U1 1 U2 1 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0008-4204 J9 CAN J PHYS JI Can. J. Phys. PD NOV-DEC PY 2001 VL 79 IS 11-12 BP 1333 EP 1338 DI 10.1139/cjp-79-11-12-1333 PG 6 WC Physics, Multidisciplinary SC Physics GA 506QJ UT WOS:000172983000005 ER PT J AU Meron, E Bar, M Hagberg, A Thiele, U AF Meron, E Bar, M Hagberg, A Thiele, U TI Front dynamics in catalytic surface reactions SO CATALYSIS TODAY LA English DT Article; Proceedings Paper CT Workshop on Spatiotemporal Catalytic Patterns CY OCT 15-17, 2000 CL HAIFA, ISRAEL SP Volkswagen Stif, Minerva Ctr Phys Complex Syst, Chem Engn Dept & Techn, Israel Inst Technol DE catalytic reaction; anisotropy; front instabilities; stratified chaos ID REACTION-DIFFUSION-SYSTEMS; ORDER-PARAMETER EQUATIONS; PATTERN-FORMATION; CHEMICAL WAVES; CURVED FRONTS; CO OXIDATION; PROPAGATION; TRANSITIONS; BIFURCATIONS; TURBULENCE AB A variety of pattern formation phenomena in catalytic surface reactions can be attributed to the dynamics of interfaces, or fronts, separating distinct uniform states. The states may represent surface coverages by different adsorbates or in the case of forced oscillations, different phases of oscillation. The dynamics of fronts are strongly affected by front instabilities and by diffusion anisotropy. We identify two new pattern formation mechanisms associated with different front behaviors in orthogonal directions: an ordering process by which stationary labyrinths in an isotropic system evolve into ordered stationary stripes, and confinement of isotropic spatiotemporal chaos to one space dimension, a state we term stratified chaos. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Ben Gurion Univ Negev, Dept Solar Energy & Environm Phys, BIDR, IL-84990 Sede Boqer, Israel. Ben Gurion Univ Negev, Dept Phys, IL-84105 Beer Sheva, Israel. Max Planck Inst Phys Komplexer Syst, D-01187 Dresden, Germany. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Complutense Madrid, Inst Pluridisciplinar, E-28040 Madrid, Spain. RP Meron, E (reprint author), Ben Gurion Univ Negev, Dept Solar Energy & Environm Phys, BIDR, Sede Boker Campus, IL-84990 Sede Boqer, Israel. RI MERON, EHUD/F-1810-2012; Bar, Markus/B-8396-2011; thiele, uwe/B-6236-2008 OI Bar, Markus/0000-0002-6935-7759; thiele, uwe/0000-0001-7989-9271 NR 41 TC 4 Z9 4 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 J9 CATAL TODAY JI Catal. Today PD NOV 1 PY 2001 VL 70 IS 4 BP 331 EP 340 DI 10.1016/S0920-5861(01)00341-8 PG 10 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 502YZ UT WOS:000172771500006 ER PT J AU Nolan, JP Mandy, FF AF Nolan, JP Mandy, FF TI Suspension array technology: New tools for gene and protein analysis SO CELLULAR AND MOLECULAR BIOLOGY LA English DT Article; Proceedings Paper CT National Meeting of the Research Inrastructure in Minority Institutions Program (RIMI) CY FEB, 2000 CL ATLANTA, GEORGIA SP Res Infrastructure Minority Inst Program DE genomics; proteomics; screening; diagnostics; throughput ID FLOW CYTOMETRIC ANALYSIS; HIGH-THROUGHPUT; HYBRIDIZATION; QUANTITATION; BINDING; ASSAY; MICROSPHERES; DETERMINANTS; FLUORESCENCE; SPECIFICITY AB Flow cytometry has long been a key tool in the analysis of lymphocytes and other cells, owing to its ability to make quantitative, homogeneous, multiparameter measurements of particles. New developments in illumination sources, digital signal processing and microsphere chemistry are driving the development of flow cytometry in new areas of biomedical research. In particular, the maturation of approaches to perform highly parallel analyses using suspension arrays of microspheres with different morphospectral features is making flow cytometry an important tool in protein and genetic analysis. In this paper, we review the development of suspension array technology (SAT), current applications in protein and genomic analysis, and the prospects for this platform in a variety of large scale screening applications. C1 Los Alamos Natl Lab, Biosci Div, Natl Flow Cytometry Resouces, Los Alamos, NM 87545 USA. Hlth Canada, Natl Lab HIV Immunol, Ottawa, ON, Canada. RP Nolan, JP (reprint author), Los Alamos Natl Lab, Biosci Div, Natl Flow Cytometry Resouces, POB 1663, Los Alamos, NM 87545 USA. NR 44 TC 54 Z9 67 U1 3 U2 9 PU CELLULAR & MOLECULAR BIOLOGY PI NOISY-LE-GRAND PA PROF R WEGMANN RESIDENCE HAUSSMANN 1 AVENUE DU PAVE NEUF, 93160 NOISY-LE-GRAND, FRANCE SN 0145-5680 J9 CELL MOL BIOL JI Cell. Mol. Biol. PD NOV PY 2001 VL 47 IS 7 BP 1241 EP 1256 PG 16 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 517AV UT WOS:000173589700020 PM 11838973 ER PT J AU Pasini, D Klopp, JM Frechet, JMJ AF Pasini, D Klopp, JM Frechet, JMJ TI Design, synthesis, and characterization of carbon-rich cyclopolymers for 193 nm microlithography SO CHEMISTRY OF MATERIALS LA English DT Article ID EXCIMER-LASER LITHOGRAPHY; SINGLE-LAYER RESISTS; ALICYCLIC POLYMERS; ETCH RESISTANCE; ORGANIC MATERIALS; AMINO-ACIDS; PHOTORESISTS; DERIVATIVES; METHACRYLATE; POLYMERIZATION AB A series of cyclopolymers designed for use in 193 nm photoresist materials has been synthesized and characterized. These novel materials that provide both optical transparency at 193 nm and also reactive ion etch resistance are obtained via cyclopolymerization of suitably designed bifunctional monomers incorporating acrylic and olefinic double bonds. The approach is highly versatile and allows the preparation of a broad array of structurally related materials with different substituents providing the imaging function and the desired level of etch resistance. The cyclopolymerization process is experimentally forgiving, enabling control of the molecular weight as well as the incorporation of comonomers such as acrylic acid or maleic anhydride to fine-tune the lithographic properties. C1 Univ Calif Berkeley, Dept Chem, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA USA. RP Frechet, JMJ (reprint author), Univ Calif Berkeley, Dept Chem, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. EM frechet@cchem.berkeley.edu RI Pasini, Dario/H-5628-2011; OI Pasini, Dario/0000-0002-8273-3798; Frechet, Jean /0000-0001-6419-0163 NR 62 TC 25 Z9 25 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD NOV PY 2001 VL 13 IS 11 BP 4136 EP 4146 DI 10.1021/cm0104304 PG 11 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 495CY UT WOS:000172323700054 ER PT J AU Klopp, JM Pasini, D Byers, JD Willson, CG Frechet, JMJ AF Klopp, JM Pasini, D Byers, JD Willson, CG Frechet, JMJ TI Microlithographic assessment of a novel family of transparent and etch-resistant chemically amplified 193-nm resists eased on cyclopolymers SO CHEMISTRY OF MATERIALS LA English DT Article ID SCANNING PROBE LITHOGRAPHY; SINGLE-LAYER RESISTS; ALICYCLIC POLYMERS; NM MICROLITHOGRAPHY; ORGANIC MATERIALS; DERIVATIVES; PERFORMANCE; MONOLAYERS; DESIGN AB The evaluation and structural optimization of a family of single layer, positive tone, chemically amplified resists for 193-nm lithography is presented. The resists are formulated from cyclopolymeric materials in which the nature, etch properties, and spatial disposition of the substituents are systematically varied. Their lithographic performance is evaluated on the basis of the interplay between chemical structure, molecular weight, and comonomer composition. These materials have good optical clarity at the desired wavelength, excellent resolution to ca. 90 nm with a phase-shifting mask, and outstanding reactive ion etch resistance. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA USA. RP Frechet, JMJ (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM frechet@cchem.berkeley.edu RI Pasini, Dario/H-5628-2011; OI Pasini, Dario/0000-0002-8273-3798; Frechet, Jean /0000-0001-6419-0163 NR 33 TC 25 Z9 26 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD NOV PY 2001 VL 13 IS 11 BP 4147 EP 4153 DI 10.1021/cm010431w PG 7 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 495CY UT WOS:000172323700055 ER PT J AU Wiederrecht, GP Sandi, G Carrado, KA Seifert, S AF Wiederrecht, GP Sandi, G Carrado, KA Seifert, S TI Intermolecular dimerization within pillared, layered clay templates SO CHEMISTRY OF MATERIALS LA English DT Article ID AROMATIC-HYDROCARBONS; PHOTOPHYSICAL PROBE; LITHIUM BATTERIES; PYRENE; FLUORESCENCE; SYSTEMS; MONTMORILLONITES; ASSOCIATION; EMISSION; ZEOLITES AB Solutions of pyrene in the presence of a pillared, layered montmorillonite clay produce hybrid organic-inorganic materials with substantial molecular loading in the gallery regions between the clay layers. The results are in sharp contrast to other aromatics, such as benzene, naphthalene, or perylene, which show minimal incorporation of the molecules into the gallery regions of the clay. We present evidence that the unusual affinity for pyrene to form intermolecular dimers is the reason for the high loading. Pyrene monomers are easily introduced to the layers. Through steric hindrance, subsequent intermolecular dimer formation is allowed, and they are captured by the pillared, layered structure. CW and time-resolved emission spectra strongly indicate the presence of face-to-face intermolecular dimers (excimers) within the clay galleries. The combination of the ease of high molecular loading into an inorganic, high aspect ratio template and the collective optical properties of the organic layer may be useful as a new means to create hybrid structures. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Wiederrecht, GP (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 35 TC 15 Z9 15 U1 2 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD NOV PY 2001 VL 13 IS 11 BP 4233 EP 4238 DI 10.1021/cm010262f PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 495CY UT WOS:000172323700067 ER PT J AU Mahurin, S McGinnis, M Bogard, JS Hulett, LD Pagni, RM Compton, RN AF Mahurin, S McGinnis, M Bogard, JS Hulett, LD Pagni, RM Compton, RN TI Effect of beta radiation on the crystallization. of sodium chlorate from water: A new type of asymmetric synthesis SO CHIRALITY LA English DT Article; Proceedings Paper CT 12th International Symposium on Chiral Discrimination (CHIRALITY 2000) CY SEP 24-28, 2000 CL CHAMONIX MONT BLANC, FRANCE DE sodium chlorate crystals; asymmetric crystallization; beta radiation; polarized electrons; radiolysis of water; positron radiation ID CHIRAL-SYMMETRY-BREAKING; ORIGINS; PARITY; DECAY AB Sodium chlorate is an achiral molecule that crystallizes from water in the chiral space group P2(1)3. In the absence of chiral perturbations, a random distribution of (+) and (-) crystals is obtained. Kondepudi(2) has shown that constantly stirring an evaporating NaClO3 solution gives mostly either (+) or (-) crystals. Repeating this experiment many times gives equal numbers of (+) and (-) sets of crystals. Herein we report that when evaporating aqueous NaClO3, is subjected to beta particles from an Sr-90 source,, an asymmetric distribution of (+) and (-) crystals favoring the (+) crystals is obtained. The beta. particles are energetic polarized electrons that are approximately 80% of left-handed helicity. By a poorly understood mechanism, the spin polarized electrons produce chiral nucleating sites that favor formation of the (+)-NaClO3 crystals. Exposure of the evaporating solution instead to energetic positrons from an Na-22 source yields mainly (-)-NaClO3 crystals. Polarized positrons are of predominantly tight-handed helicity. One may conclude that the chirality of the radiation is correlated with the chirality of the crystals being generated. (C) 2001 Wiley-Liss, Inc. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Pagni, RM (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 27 TC 18 Z9 19 U1 2 U2 6 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0899-0042 J9 CHIRALITY JI Chirality PD NOV PY 2001 VL 13 IS 10 SI SI BP 636 EP 640 DI 10.1002/chir.10007 PG 5 WC Chemistry, Medicinal; Chemistry, Analytical; Chemistry, Organic; Pharmacology & Pharmacy SC Pharmacology & Pharmacy; Chemistry GA 489RN UT WOS:000172005600008 PM 11746795 ER PT J AU Zantek, ND Walker-Daniels, J Stewart, J Hansen, RK Robinson, D Miao, H Wang, BC Kung, HJ Bissell, MJ Kinch, MS AF Zantek, ND Walker-Daniels, J Stewart, J Hansen, RK Robinson, D Miao, H Wang, BC Kung, HJ Bissell, MJ Kinch, MS TI MCF-10A-NeoST: A new cell system for studying cell-ECM and cell-cell interactions in breast cancer SO CLINICAL CANCER RESEARCH LA English DT Article ID RECEPTOR TYROSINE KINASE; MAMMARY EPITHELIAL-CELLS; FOCAL ADHESIONS; E-CADHERIN; VASCULOGENIC MIMICRY; EXTRACELLULAR-MATRIX; INTEGRIN RECEPTORS; PROTEIN-KINASES; TUMOR INVASION; GROWTH AB Purpose: There is a continuing need for genetically matched cell systems to model cellular behaviors that are frequently observed in aggressive breast cancers. Experimental Design: We report here the isolation and initial characterization of a spontaneously arising variant of MCF-10A. cells, NeoST, which provides a new model to study cell adhesion and signal transduction in breast cancer. Results: NeoST cells recapitulate important biological and biochemical features of metastatic breast cancer, including anchorage-independent growth, invasiveness in three-dimensional reconstituted membranes, loss of E-cadherin expression, and increased tyrosine kinase activity. A comprehensive analysis of tyrosine kinase expression revealed overexpression or functional activation of the Axl, FAK, and EphA2 tyrosine kinases in transformed MCF-10A cells. Conclusions: MCF-10A and these new derivatives provide a genetically matched model to study defects in cell adhesion and signaling that are relevant to cellular behaviors that often typify aggressive breast cancer cells. C1 Purdue Univ, Dept Basic Med Sci, W Lafayette, IN 47905 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Biol Chem, Sacramento, CA 95817 USA. Case Western Reserve Univ, Rammelkamp Ctr Res, Cleveland, OH 44109 USA. RP Kinch, MS (reprint author), Purdue Univ, Dept Basic Med Sci, W Lafayette, IN 47905 USA. RI Kung, Hsing-Jien/C-7651-2013; OI Kinch, Michael/0000-0003-3939-3756 FU NCI NIH HHS [CA 57621, CA 64786, CA 85615, R01 CA057621-07, R01 CA064786-04A1, R21 CA085615-01] NR 64 TC 46 Z9 51 U1 0 U2 5 PU AMER ASSOC CANCER RESEARCH PI BIRMINGHAM PA PO BOX 11806, BIRMINGHAM, AL 35202 USA SN 1078-0432 J9 CLIN CANCER RES JI Clin. Cancer Res. PD NOV PY 2001 VL 7 IS 11 BP 3640 EP 3648 PG 9 WC Oncology SC Oncology GA 491JX UT WOS:000172106200047 PM 11705887 ER PT J AU Smilowitz, HM Coderre, JA Nawrocky, MM Tu, W Pinkerton, A Jahng, GH Gebbers, N Slatkin, DN AF Smilowitz, HM Coderre, JA Nawrocky, MM Tu, W Pinkerton, A Jahng, GH Gebbers, N Slatkin, DN TI The combination of X-ray-mediated radiosurgery and gene-mediated immunoprophylaxis for advanced intracerebral gliosarcomas in rats. SO CLINICAL CANCER RESEARCH LA English DT Meeting Abstract C1 Univ Connecticut, Ctr Hlth, Farmington, CT USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC CANCER RESEARCH PI BIRMINGHAM PA PO BOX 11806, BIRMINGHAM, AL 35202 USA SN 1078-0432 J9 CLIN CANCER RES JI Clin. Cancer Res. PD NOV PY 2001 VL 7 IS 11 SU S MA 484 BP 3751S EP 3751S PG 1 WC Oncology SC Oncology GA 491RE UT WOS:000172121800477 ER PT J AU Rodi, DJ Agoston, GE Manon, R Lapcevich, R Green, SJ Makowski, L AF Rodi, DJ Agoston, GE Manon, R Lapcevich, R Green, SJ Makowski, L TI Identification of small molecule binding sites within proteins using phage display technology SO COMBINATORIAL CHEMISTRY & HIGH THROUGHPUT SCREENING LA English DT Article ID ENDOGENOUS MAMMALIAN METABOLITE; HYALURONIC-ACID; CELL-PROLIFERATION; MITOTIC BLOCK; PEPTIDE-MHC; DNA-BINDING; V3 LOOP; BCL-2; DOMAIN; TAXOL AB Affinity selection of peptides displayed on phage particles was used as the basis for mapping molecular contacts between small molecule ligands and their protein targets. Analysis of the crystal structures of complexes between proteins and small molecule ligands revealed that virtually all ligands of molecular weight 300 Da or greater have a continuous binding epitope of 5 residues or more. This observation led to the development of a technique for binding site identification which involves statistical analysis of an affinity-selected set of peptides obtained by screening of libraries of random, phage-displayed peptides against small molecules attached to solid surfaces. A random sample of the selected peptides is sequenced and used as input for a similarity scanning program which calculates cumulative similarity scores along the length of the putative receptor. Regions of the protein sequence exhibiting the highest similarity with the selected peptides proved to have a high probability of being involved in ligand binding. This technique has been employed successfully to map the contact residues in multiple known targets of the anticancer drugs paclitaxel (Taxol(TM)), docetaxel (Taxotere(TM)) and 2-methoxestradiol and the glycosaminoglycan hyaluronan, and to identify a novel paclitaxel receptor [1]. These data corroborate the observation that the binding properties of peptides displayed on the surface of phage particles can mimic the binding properties of peptides in naturally occurring proteins. It follows directly that structural context is relatively unimportant for determining the binding properties of these disordered peptides. This technique represents a novel, rapid, high resolution method for identifying potential ligand binding sites in the absence of three-dimensional information and has the potential to greatly enhance the speed of development of novel small molecule pharmaceuticals. C1 EntreMed Inc, Dept Discovery Res, Rockville, MD 20850 USA. Florida State Univ, Inst Mol Biophys, Tallahassee, FL 32301 USA. RP Makowski, L (reprint author), Argonne Natl Lab, Div Biosci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 79 TC 31 Z9 32 U1 0 U2 4 PU BENTHAM SCIENCE PUBL LTD PI HILVERSUM PA PO BOX 1673, 1200 BR HILVERSUM, NETHERLANDS SN 1386-2073 J9 COMB CHEM HIGH T SCR JI Comb. Chem. High Throughput Screen PD NOV PY 2001 VL 4 IS 7 BP 553 EP 572 PG 20 WC Biochemical Research Methods; Chemistry, Applied; Pharmacology & Pharmacy SC Biochemistry & Molecular Biology; Chemistry; Pharmacology & Pharmacy GA 481WF UT WOS:000171542900004 PM 11562259 ER PT J AU Stevens, FJ AF Stevens, FJ TI Caveat receptor: Proteomes on display SO COMBINATORIAL CHEMISTRY & HIGH THROUGHPUT SCREENING LA English DT Article ID PHAGE-DISPLAY; PEPTIDE; PROTEIN; ANTIBODIES; PROLINE; BINDING AB Display methods development is currently extending the application of this strategy beyond the generation of ligand binding reagents for research, clinical, or biotechnological purposes to its use as a primary research tool Peptide- and cDNA display methods have the potential to contribute to understanding the mechanisms of certain classes of drugs and to help map protein-protein interactions of physiological importance. Although the critical contribution of comprehensive amino acid sequence databases has been recognized, of equal importance might be structural genomics concepts in the application of display system technology to proteomics research. Lessons learned from the study of antibody-antigen interactions are reviewed here and applied to the field of display technology with the goal of delineating major factors involved in the successful mimicry of natural protein-ligand interactions. C1 Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. RP Stevens, FJ (reprint author), Argonne Natl Lab, Biosci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. FU NIDDK NIH HHS [DK43757] NR 13 TC 0 Z9 0 U1 0 U2 0 PU BENTHAM SCIENCE PUBL LTD PI HILVERSUM PA PO BOX 1673, 1200 BR HILVERSUM, NETHERLANDS SN 1386-2073 J9 COMB CHEM HIGH T SCR JI Comb. Chem. High Throughput Screen PD NOV PY 2001 VL 4 IS 7 BP 599 EP 602 PG 4 WC Biochemical Research Methods; Chemistry, Applied; Pharmacology & Pharmacy SC Biochemistry & Molecular Biology; Chemistry; Pharmacology & Pharmacy GA 481WF UT WOS:000171542900008 PM 11562263 ER PT J AU Shepherd, IG Cheng, RK AF Shepherd, IG Cheng, RK TI The burning rate of premixed flames in moderate and intense turbulence SO COMBUSTION AND FLAME LA English DT Article ID FLOWS AB Burning rate measurements have been performed in lean (phi = 0.7) premixed methane/air flames stabilized on a low-swirl burner in moderate and intense turbulence. (Ret 460-1400). The purpose of this paper is to reconcile the burning rate determined by two widely used experimental methods: flow-velocity measurements and scalar measurements of the flame-surface density, Sigma. The two sets of measurements, of conditional mass fluxes by Laser Doppler Velocimetry (LDV) and flame-surface density, were determined from the instantaneous flame-front positions obtained from OH Planar Laser Induced Fluorescence (OH-PLIF) images. It is important when making these comparisons to distinguish two measures of the turbulent burning velocity: the displacement, S-D, and consumption speed, S-C. Measurement of the consumption speed by the conditional flux method using laser Doppler velocimetry can account for the multidimensional affects of burner/flow geometry. In this burner geometry S-C was found to be 30% of the cold-boundary flow velocity, S-D. Both the turbulent displacement and consumption velocities were found to have linear dependencies on u'/S-L for values up to u'/S-L similar to7.3. The consumption speed is the more fundamental measure of the burning rate and is directly comparable to that derived from integration of flame-surface-density measurements. The similarity of the scalar and mass flux burning rates indicates that measurements of Sigma. which are usually much simpler to perform than the flux measurements. can be used to test theoretical models and investigate the affect of upstream turbulence parameters on global flame-burning characteristics. Furthermore, comparison of the flux and scalar measurements has shown that even at flow/flame conditions above the Klimov-Williams criterion the affect of the turbulence on the local laminar burning rate, as expected from the Markstein number for this mixture, is small in the mean, Preliminary comparisons with models have been performed. (C) 2001 by The Combustion Institute. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, EETC, Adv Energy Technol Dept, Berkeley, CA 94720 USA. RP Shepherd, IG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, EETC, Adv Energy Technol Dept, Mail Stop B29C,108th,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 22 TC 77 Z9 80 U1 2 U2 19 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD NOV PY 2001 VL 127 IS 3 BP 2066 EP 2075 DI 10.1016/S0010-2180(01)00309-1 PG 10 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 499ZP UT WOS:000172601400003 ER PT J AU Barlow, RS Karpetis, AN Frank, JH Chen, JY AF Barlow, RS Karpetis, AN Frank, JH Chen, JY TI Scalar profiles and NO formation in laminar opposed-flow partially premixed methane/air flames SO COMBUSTION AND FLAME LA English DT Article ID JET DIFFUSION FLAME; NITRIC-OXIDE; TEMPERATURE AB Measurements of temperature. the major species (N-2, O-2, CH4, CO2, H2O, CO, and H-2), OH, and NO are obtained in steady laminar opposed-flow partially premixed flames of methane and air, using the non-intrusive techniques of Raman scattering and laser-induced fluorescence. Flames having fuel-side equivalence ratios of phi = 3.17. 2.17. and 1.8 are stabilized on a porous cylindrical burner (Tsuji burner) in a low-velocity flow of air. Results are compared with calculations using a version of the Sandia laminar flame code that is formulated for the Tsuji geometry and includes an optically thin treatment of radiation. Because velocity profiles are not measured, the strain rate in each calculation is adjusted to match the measured profile of the mixture fraction. Measured profiles of temperature and species mass fractions are then compared with results of calculations using the GRI-Mech 2.11 and 3.0 chemical mechanisms, as well as a detailed mechanism from Miller. All three mechanisms give agreement with experimental results for the major species that is generally within experimental Uncertainty. With regard to NO formation. the relative performance of the three mechanisms depends on the fuel-Side equivalence ratio. GRI-Mech 2.11 gives reasonably good agreement with measured NO levels in lean and near-stoichiometric conditions. but it under predicts NO levels in fuel-rich conditions. GRI-Mech 3.0 significantly over predicts the peak NO levels the phi = 3.17 and 2.17 flames. but it yields relatively good agreement with measurements in the phi = 1.8 flame. The Miller mechanism gives good agreement with measured NO levels in the phi = 3.17 flame. but it progressively over predicts peak NO levels in the leaner flames, Comparisons of adiabatic and radiative calculations show that radiation can have a significant effect on the width and Structure of partially premix:ed flames. as well as on the levels of NO produced. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Barlow, RS (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 27 TC 232 Z9 237 U1 2 U2 35 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD NOV PY 2001 VL 127 IS 3 BP 2102 EP 2118 DI 10.1016/S0010-2180(01)00313-3 PG 17 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 499ZP UT WOS:000172601400006 ER PT J AU Margolis, SB Telengator, AM AF Margolis, SB Telengator, AM TI Influence of sublimation and pyrolysis on quasi-steady deflagrations in confined porous energetic materials SO COMBUSTION AND FLAME LA English DT Article ID GAS PERMEATION; 2-PHASE FLOW; PROPELLANT AB Deflagrations in porous energetic materials under confinement are generally characterized by a relatively rapid increase in the burning rate as the pressure difference, or overpressure, in the burned-gas region relative to that deep within the pores of the unburned solid increases. Specifically, there appears to be a range of overpressures in which the sensitivity, or slope, of the propagation speed as a function of overpressure transitions from relatively small to large values. This effect has been qualitatively attributed to the fact that a sufficient overpressure reverses the gas flow and thus allows the burned gas to permeate, and therefore preheat, the porous material. However, quantitative descriptions of both the process itself and the corresponding burning-rate dependencies have only recently been achieved. The present work reflects a further refinement in this analytical description in that the melt layer, which underlies several previous studies and is likely to exist only at modest overpressures, is replaced by sublimation and pyrolysis at the material surface, followed by an attached gas flame that converts the unburned gaseous reactants to final products. As a result, gaseous reactants as well as products now permeate the porous solid, thereby affecting the propagation speed significantly and modifying both the combustion-wave structure and the transition to convection-enhanced burning. (C) 2001 by The Combustion Institute. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. RP Margolis, SB (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 16 TC 8 Z9 8 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD NOV PY 2001 VL 127 IS 3 BP 2135 EP 2156 DI 10.1016/S0010-2180(01)00320-0 PG 22 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 499ZP UT WOS:000172601400009 ER PT J AU Jadach, S Placzek, W Skrzypek, M Ward, BFL Was, Z AF Jadach, S Placzek, W Skrzypek, M Ward, BFL Was, Z TI The Monte Carlo event generator YFSWW3 version 1.16 for W-pair production and decay at LEP2/LC energies SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article ID (UN)STABLE W+W PRODUCTION; FRAUTSCHI-SUURA EXPONENTIATION; QED RADIATIVE-CORRECTIONS; E+E-ANNIHILATION; NONFACTORIZABLE CORRECTIONS; HELICITY AMPLITUDES; BHABHA SCATTERING; E(+)E(-) COLLISIONS; UNSTABLE PARTICLES; PROGRAM BHLUMI AB We present the Monte Carlo event generator YFSWW3 version 1.16 for the process of W-pair production and decay in electron-positron collisions. It includes O(alpha) electroweak radiative corrections in the WW production stage together with the O(alpha (3)) initial-state-radiation (ISR) corrections in the leading-logarithmic (LL) approximation, implemented within the Yennie-Frautschi-Suura (YFS) exclusive exponentiation framework. The photon radiation in the W decays is generated by the dedicated program PHOTOS up to O(alpha (2)) LL, normalized to the W branching ratios. The program is interfaced with the tau decay library TAUOLA and the quark fragmentation/hadronization package JETSET. The semi-analytical code Korwan for the calculations of the differential and total cross-sections at the Born level and in the ISR approximation is included. (C) 2001 Elsevier Science B.V. All rights reserved. C1 DESY Zeuthen, D-15738 Zeuthen, Germany. Inst Nucl Phys, PL-30055 Krakow, Poland. CERN, CH-1211 Geneva, Switzerland. Jagiellonian Univ, Inst Comp Sci, PL-30072 Krakow, Poland. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Jadach, S (reprint author), DESY Zeuthen, Platanenallee 6, D-15738 Zeuthen, Germany. NR 54 TC 84 Z9 84 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD NOV 1 PY 2001 VL 140 IS 3 BP 432 EP 474 DI 10.1016/S0010-4655(01)00288-0 PG 43 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 490DY UT WOS:000172036200013 ER PT J AU Jadacha, S Placzek, W Skrzypek, M Ward, BFL Was, Z AF Jadacha, S Placzek, W Skrzypek, M Ward, BFL Was, Z TI The Monte Carlo program KoralW version 1.51 and the concurrent Monte Carlo KoralW&YFSWW3 with all background graphs and first-order corrections to W-pair production SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article ID (UN)STABLE W+W PRODUCTION; FERMIONS PLUS GAMMA; RADIATIVE-CORRECTIONS; EVENT GENERATOR; 4-FERMION PRODUCTION; E(+)E(-) COLLISIONS; LEP2 ENERGIES; HELICITY AMPLITUDES; E+E ANNIHILATION; FINAL-STATES AB The version 1.51 of the Monte Carlo (MC) program KoralW for all e(+)e(-) --> f(1)f(2)f(3)f(4) processes is presented. The most important change from the previous version 1.42 is the facility for writing MC events on the mass storage device and reprocessing them later on. In the reprocessing parameters of the Standard Model may be modified in order to fit them to experimental data. Another important new feature is the possibility of including complete O(a) corrections to double-resonant W-pair component-processes in addition to all background (non-WW) graphs. The inclusion is done with the help of the YFSWW3 MC event generator for fully exclusive differential distributions (event per event). Technically, it is done in such a way that YFSWW3 runs concurrently with Kora1W as a separate slave process, reading momenta of the MC event generated by KoralW and returning the correction weight to KoralW. The latter introduces the O(alpha) correction using this weight, and finishes processing the event (rejection due to total MC weight, hadronization, etc.). The communication between KoralW and YFSWW3 is done with the help of the FIFO facility of the UNIX/Linux operating system. This does not require any modifications of the FORTRAN source codes. From the user's point of view, the resulting Concurrent MC event generator KoralW&YFSWW3 looks as a regular single MC event generator with all the standard features. (C) 2001 Elsevier Science B.V All rights reserved. C1 CERN, Div Theory, CH-1211 Geneva 23, Switzerland. Inst Nucl Phys, PL-30055 Krakow, Poland. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Jagiellonian Univ, Inst Comp Sci, Krakow, Poland. RP Jadacha, S (reprint author), CERN, Div Theory, CH-1211 Geneva 23, Switzerland. NR 40 TC 80 Z9 80 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD NOV 1 PY 2001 VL 140 IS 3 BP 475 EP 512 DI 10.1016/S0010-4655(01)00296-X PG 38 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 490DY UT WOS:000172036200014 ER PT J AU Owen, JM AF Owen, JM TI An open-source project for modeling hydrodynamics in astrophysical systems SO COMPUTING IN SCIENCE & ENGINEERING LA English DT Article ID SMOOTHED PARTICLE HYDRODYNAMICS C1 Lawrence Livermore Natl Lab, A Div, Livermore, CA 94551 USA. RP Owen, JM (reprint author), Lawrence Livermore Natl Lab, A Div, POB 808,MS L-38, Livermore, CA 94551 USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1521-9615 J9 COMPUT SCI ENG JI Comput. Sci. Eng. PD NOV-DEC PY 2001 VL 3 IS 6 BP 54 EP 59 DI 10.1109/5992.963428 PG 6 WC Computer Science, Interdisciplinary Applications SC Computer Science GA 483UU UT WOS:000171654900009 ER PT J AU Tribble, DL AF Tribble, DL TI Antioxidants and atherosclerotic cardiovascular disease: unresolved issues SO CORONARY ARTERY DISEASE LA English DT Review DE oxidation; antioxidants; cardiovascular disease; atherosclerosis; lipoprotein ID CORONARY HEART-DISEASE; VITAMIN-E CONSUMPTION; ALPHA-TOCOPHEROL; BETA-CAROTENE; ARTERY WALL; SUPPLEMENTATION; RISK; TRIAL; PROGRESSION; POPULATION C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Mol & Nucl Med, Berkeley, CA 94720 USA. RP Tribble, DL (reprint author), Merck & Co Inc, Merck Res Labs, RY32-557,126 E Lincoln Ave,POB 2000, Rahway, NJ 07065 USA. NR 29 TC 3 Z9 4 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0954-6928 J9 CORONARY ARTERY DIS JI Coronary Artery Dis. PD NOV PY 2001 VL 12 IS 7 BP 541 EP 546 DI 10.1097/00019501-200111000-00003 PG 6 WC Cardiac & Cardiovascular Systems SC Cardiovascular System & Cardiology GA 495CL UT WOS:000172322600003 PM 11714993 ER PT J AU Machida, M Tachiki, M AF Machida, Masahiko Tachiki, Masashi TI Terahertz electromagnetic wave emission by using intrinsic Josephson junctions of high-Tc superconductors SO CURRENT APPLIED PHYSICS LA English DT Article DE High-Tc compound; Intrinsic Josephson effect; Terahertz emission device AB High-Tc cuprate superconductors like Bi2Sr2CaCu2O8+y (Bi-2212) show very large anisotropy in the electrical conduction. Inside the CuO2 plan the conduction looks like that in good metals, while the block layers located between CuO2 planes behave like insulating barriers. Thus, neighboring CuO2 layers are linked by the Josephson coupling in superconducting states, and the Bi-2212 single crystal can be regarded as a natural serial array of Josephson junctions along the e-axis. It has been found out that in such a system a unique excitation mode called the collective Josephson plasma exists. The mode collectively oscillates along the e-axis, while it propagates along any direction ranged from the ab-plane to the e-axis. If the mode can be coherently excited, the system should be very useful as a device generating strong electromagnetic wave emission. In this paper we review a theoretical framework describing the Josephson plasma modes. The Josephson vortex penetrates into the sample under the magnetic field parallel to the CuO2 plane and it moves along the ab-plane under an external current parallel to the e-axis. In the vortex flow state, the vortex speed can reach and exceed the propagating velocities of the Josephson plasma modes due to very weak dissipation. Then, the vortices strongly couple with the plasma modes and change their flowing lattice configurations into patterns dependent on the interacting plasma mode profiles. Among many expected flow patterns, we pay attention to a special state resonating with a plasma mode in-phase along the e-axis because all junctions synchronize in such a state. Large-scale numerical simulations by Machida et al. confirmed that the special state characterized by the rectangular lattice stably appears in a wide range of I-V characteristics. In this paper, we report their recent simulation results. (C) 2001 Elsevier Science B.V. All rights reserved. C1 [Tachiki, Masashi] Natl Inst Mat Sci, Tsukuba, Ibaraki 3050047, Japan. [Machida, Masahiko] Argonne Natl Lab, Argonne, IL 60439 USA. [Machida, Masahiko] Japan Atom Energy Res Inst, Meguro Ku, Tokyo 1530061, Japan. [Machida, Masahiko] CREST JST, Meguro Ku, Tokyo 1530061, Japan. RP Tachiki, M (reprint author), Natl Inst Mat Sci, Sengen 1-2-1, Tsukuba, Ibaraki 3050047, Japan. EM mac@koma.jaeri.go.jp; tachiki@kkjj.crest.jst.go.jp NR 17 TC 10 Z9 10 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1567-1739 J9 CURR APPL PHYS JI Curr. Appl. Phys. PD NOV PY 2001 VL 1 IS 4-5 BP 341 EP 348 AR PII S1567-1739(01)00033-5 DI 10.1016/S1567-1739(01)00033-5 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA V23CA UT WOS:000208319700016 ER PT J AU Krauss, AR Auciello, O Gruen, DM Jayatissa, A Sumant, A Tucek, J Mancini, DC Moldovan, N Erdemir, A Ersoy, D Gardos, MN Busmann, HG Meyer, EM Ding, MQ AF Krauss, AR Auciello, O Gruen, DM Jayatissa, A Sumant, A Tucek, J Mancini, DC Moldovan, N Erdemir, A Ersoy, D Gardos, MN Busmann, HG Meyer, EM Ding, MQ TI Ultrananocrystalline diamond thin films for MEMS and moving mechanical assembly devices SO DIAMOND AND RELATED MATERIALS LA English DT Article DE ultrananocrystalline; diamond thin films; assembly devices ID NANOCRYSTALLINE DIAMOND; MICROWAVE PLASMAS; GRAIN-BOUNDARIES; CVD DIAMOND; GROWTH; FABRICATION; TECHNOLOGY; PRECURSORS; FRICTION; SURFACE AB MEMS devices are currently fabricated primarily in silicon because of the available surface machining technology. A major problem with the Si-based MEMS technology is that Si has poor mechanical and tribological properties [J.J. Sniegowski, in: B. Bushan (Ed.), Tribology Issues and Opportunities in MEMS, Kluwer Academic Publisher, The Netherlands, 1998, p. 325; A.P. Lee, A.P. Pisano, M.G. Lim, Mater. Res. Soc. Symp. Proc. 276 (1992) 67.], and practical MEMS devices are currently limited primarily to applications involving only bending and flexural motion, such as cantilever accelerometers and vibration sensors. However, because of the poor flexural strength and fracture toughness of Si, and the tendency of Si to adhere to hydrophilic surfaces, even these simple devices have limited dynamic range. Future MEMS applications that involve significant rolling or sliding contact will require the use of new materials with significantly improved mechanical and tribological properties, and the ability to perform well in harsh environments, Diamond is a superhard material of high mechanical strength, exceptional chemical inertness, and outstanding thermal stability. The brittle fracture strength is 23 times that of Si, and the projected wear life of diamond MEMS moving mechanical assemblies (MEMS MMAs) is 10 000 times greater than that of Si MMAs. However, as the hardest known material, diamond is notoriously difficult to fabricate. Conventional CVD thin film deposition methods offer an approach to the fabrication of ultra-small diamond structures, but the films have large grain size, high internal stress, poor intergranular adhesion, and very rough surfaces, and are consequently ill-suited for MEMS MMA applications. Diamond-like films are also being investigated for application to MEMS devices. However, they involve mainly physical vapor deposition methods that are not suitable for good conformal deposition on high aspect ratio features, and generally they do not exhibit the outstanding mechanical properties of diamond. We demonstrate here the application of a novel microwave plasma technique using a unique C-60/Ar or CH4/Ar chemistry that produces phase-pure ultrananocrystalline diamond (UNCD) coatings with morphological and mechanical properties that are ideally suited for MEMS applications in general, and MMA use in particular. We have developed lithographic techniques for the fabrication of UNCD-MEMS components, including cantilevers and multi-level devices, acting as precursors to microbearings and gears, making UNCD a promising material for the development of high performance MEMS devices. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Expt Facil Div, Argonne, IL 60439 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Univ Illinois, Dept Mat Engn, Chicago, IL USA. Raytheon Elect Syst, El Segundo, CA 90245 USA. Fraunhofer Inst Appl Mat Sci, Bremen, Germany. Univ Bremen, Inst Microsensors Actuators & Syst, Bremen, Germany. Beijing Inst Elect, Beijing, Peoples R China. RP Auciello, O (reprint author), Argonne Natl Lab, Div Mat Sci, Bldg 212,Room C210,9700 S Cass Ave, Argonne, IL 60439 USA. NR 50 TC 238 Z9 250 U1 3 U2 94 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD NOV PY 2001 VL 10 IS 11 BP 1952 EP 1961 DI 10.1016/S0925-9635(01)00385-5 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 485DN UT WOS:000171738400002 ER PT J AU Kertesz, V Van Berkel, GJ AF Kertesz, V Van Berkel, GJ TI Electropolymerization of methylene blue investigated using on-line electrochemistry/electrospray mass spectrometry SO ELECTROANALYSIS LA English DT Article DE methylene blue; azines; electropolymerization; demethylation; electrospray mass spectrometry ID ORGANIC REDOX FILMS; ELECTROCHEMICAL POLYMERIZATION; COUPLED ONLINE; SUPRAMOLECULAR PHENOMENA; NADH-OXIDATION; GOLD ELECTRODE; PLATINUM; PHENOTHIAZINE; DERIVATIVES; POLYMERS AB The initial products of the electrochemical polymerization of methylene blue were studied using a thin-layer flow cell coupled on-line with electrospray mass spectrometry. A potentiostatic technique was applied to initiate the polymerization while the soluble n-mers generated were monitored by mass spectrometry. Methylene blue dimers and trimers were observed at m/z values consistent with either "nitrogen-to-ring" coupling of the monomers or with "ring-to-ring" coupling of demethylated monomers during the electropolymerization. Experiments accomplished in D2O-based solutions prove that "nitrogen-to-ring" coupling is the dominant process. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Organ & Biol Mass Spectrometry Grp, Oak Ridge, TN 37831 USA. RI Kertesz, Vilmos/M-8357-2016 OI Kertesz, Vilmos/0000-0003-0186-5797 NR 39 TC 49 Z9 50 U1 1 U2 20 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 1040-0397 J9 ELECTROANAL JI Electroanalysis PD NOV PY 2001 VL 13 IS 17 BP 1425 EP 1430 PG 6 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA 501LY UT WOS:000172687200007 ER PT J AU Sun, X Lee, HS Yang, XQ McBreen, J AF Sun, X Lee, HS Yang, XQ McBreen, J TI Improved elevated temperature cycling of LiMn2O4 spinel through the use of a composite LiF-based electrolyte SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article ID CAPACITY LOSSES; ANION RECEPTORS; CELLS; DISSOLUTION AB A composite electrolyte containing LiF and a tris(pentafluorophenyl)borane (TPFPB) anion complexing agent displays superior thermal and electrochemical stability compared to commercial LiPF6-based electrolytes. Severe capacity fading of a Li/LiMn2O4 cell. with a commercial LiPF6 electrolyte, was observed when cycled at 55 degreesC. The capacity fading was attributed to acidic products, from salt hydrolysis and decomposition of the solvent, which degraded LiMn2O4 electrode. The composite electrolyte containing LiF and TPFPB is not moisture sensitive and does not produce acidic species. At room temperature, the composite electrolyte shows an improvement in capacity maintenance with cycling. However, at 55 degreesC the improvement is much greater. (C) 2001 The Electrochemical Society. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Sun, X (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 11 TC 49 Z9 51 U1 3 U2 26 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 1099-0062 J9 ELECTROCHEM SOLID ST JI Electrochem. Solid State Lett. PD NOV PY 2001 VL 4 IS 11 BP A184 EP A186 DI 10.1149/1.1405036 PG 3 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 481CE UT WOS:000171501700003 ER PT J AU Treimer, SE Johnson, DC AF Treimer, SE Johnson, DC TI The possibility of controlled partial anodic degradation of phenol SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article ID WASTE-WATER TREATMENT; PHOTOCATALYTIC DEGRADATION; ELECTROCHEMICAL OXIDATION; PBO2-FILM ELECTRODES; 4-CHLOROPHENOL; PATHWAY AB A metal oxide film electrode has been identified that is speculated to be useful for selective anodic conversion of phenol to acetic acid in weakly acidic (pH 3.5) 0.10 M NaNO3 under galvanostatic conditions (0.18 A cm(-2)) with irradiation from an 18 W UV light (254 nm). The film composition corresponds to 1.2% (atom/atom) Fe3+ and 0.8% (atom/atom) Mn4+ in a beta -PbO2 matrix. (C) 2001 The Electrochemical Society. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Treimer, SE (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. NR 13 TC 3 Z9 3 U1 0 U2 2 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 1099-0062 J9 ELECTROCHEM SOLID ST JI Electrochem. Solid State Lett. PD NOV PY 2001 VL 4 IS 11 BP D13 EP D15 DI 10.1149/1.1405035 PG 3 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 481CE UT WOS:000171501700007 ER PT J AU Padovani, AM Rhodes, L Riester, L Lohman, G Tsuie, B Conner, J Allen, SAB Kohl, PA AF Padovani, AM Rhodes, L Riester, L Lohman, G Tsuie, B Conner, J Allen, SAB Kohl, PA TI Porous methylsilsesquioxane for low-k dielectric applications SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article ID SPIN-ON-GLASS; CONSTANT; SILSESQUIOXANE; NANOPOROSITY AB A commercially available spin-on glass (methylsilsesquioxane, MSQ) was modified by the introduction of porosity. The porosity reduced the effective dielectric constant of the MSQ by the incorporation of air. The pores were created by adding a sacrificial polymer (substituted norbornene polymer) to the silsesquioxane matrix. The sacrificial material was thermally decomposed to form nanosize voids within the films. The physical and electrical proper-ties of the porous films were studied as a function of the reactivity of the sacrificial polymer with the glass, and the loading and molecular weight of the sacrificial polymer. Transmission electron microscopy was used to evaluate the porous microstructure. Cross-sectional images show pores of nearly spherical geometry with 5-20 nm diam. The dielectric constant and the index of refraction of the porous MSQ were lower after the decomposition of the sacrificial material. The dielectric constant decreased from 2.7 for a nonporous MSQ film to similar to2.2 for a film with 30 wt % loading of the sacrificial polymer. In a similar way, the index of refraction was reduced from 1.42 to 1.29 for the porous MSQ film. The mechanical properties were evaluated using nanoindentation techniques. This paper focuses on the significant improvements observed upon introduction of porosity to the films. The fracture toughness, or the resistance to crack propagation, increased dramatically with porosity, as compared with the nonporous MSQ films. As a result, thicker MSQ films can be fabricated without spontaneous cracking. The elastic modulus and the hardness of the porous films were measured and showed a reduction in both properties with increasing porosity in the film. (C) 2001 The Electrochemical Society. C1 Georgia Inst Technol, Sch Chem Engn, Atlanta, GA 30332 USA. BF Goodrich Co, Brecksville, OH 44141 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Motorola Inc, Austin, TX 78721 USA. RP Padovani, AM (reprint author), Georgia Inst Technol, Sch Chem Engn, Atlanta, GA 30332 USA. NR 14 TC 31 Z9 31 U1 1 U2 9 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 1099-0062 J9 ELECTROCHEM SOLID ST JI Electrochem. Solid State Lett. PD NOV PY 2001 VL 4 IS 11 BP F25 EP F28 DI 10.1149/1.1403215 PG 4 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 481CE UT WOS:000171501700009 ER PT J AU Vine, E du Pont, P Waide, P AF Vine, E du Pont, P Waide, P TI Evaluating the impact of appliance efficiency labeling programs and standards: process, impact, and market transformation evaluations SO ENERGY LA English DT Article AB Energy-efficiency labels and standards for appliances, equipment and lighting are being implemented in many countries around the world as a cornerstone of energy policy portfolios. They have a potential for very large energy savings and are very cost effective. Once appliance labeling and standards programs have been implemented, it is necessary to evaluate their effectiveness. In this paper, we describe the types of activities that need to occur in the evaluation of appliance labeling and standards programs. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Danish Energy Management AS, Dept Energy Dev & Promot, Bangkok 10400, Thailand. PW Consulting, Manchester M20 2MW, Lancs, England. RP Vine, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Bldg 90-4000, Berkeley, CA 94720 USA. NR 24 TC 15 Z9 15 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-5442 J9 ENERGY JI Energy PD NOV PY 2001 VL 26 IS 11 BP 1041 EP 1059 DI 10.1016/S0360-5442(01)00053-6 PG 19 WC Thermodynamics; Energy & Fuels SC Thermodynamics; Energy & Fuels GA 482MW UT WOS:000171580800006 ER PT J AU Dyrkacz, GR Bloomquist, CAA AF Dyrkacz, GR Bloomquist, CAA TI Solvent extraction of separated macerals in carbon disulfide/N-methylpyrrolidone SO ENERGY & FUELS LA English DT Article ID MIXED-SOLVENT; ROOM-TEMPERATURE; COAL MACERALS AB Maceral fractions derived from density separations of six coals were extracted at room temperature in carbon disulfide/N-methylpyrrolidone based media. Vitrinite was found to have the highest extract yield. Both liptinites and inertinites exhibited lower extractability. In addition, differences in extractability were found within individual fractions of the same maceral group, such as the vitrinite group. The results show that extraction of vitrinite can be a heterogeneous process where certain submaceral vitrinite particles extract differently. This may have implications for experiments that rely on extracts or residues from extractions to determine the nature of the original coal structure. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Dyrkacz, GR (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 7 Z9 11 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD NOV-DEC PY 2001 VL 15 IS 6 BP 1403 EP 1408 DI 10.1021/ef0100350 PG 6 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 495HM UT WOS:000172334500010 ER PT J AU Dyrkacz, GR Bloomquist, CAA AF Dyrkacz, GR Bloomquist, CAA TI Binary solvent extractions of upper freeport coal SO ENERGY & FUELS LA English DT Article ID CS2-N-METHYL-2-PYRROLIDINONE MIXED-SOLVENT; ROOM-TEMPERATURE; BITUMINOUS COALS; SOLUBILITY; PYRIDINE AB Different organic bases, primarily with carbon disulfide as co-solvent, were used to probe the nature of the binary solvent extractions of Upper Freeport coal. The effect of tetracyanoethylene addition on extract yields was also examined. Amides and cyclic ureas where found to all be good extractants, but were not as efficient as N-methylpyrrolidone(I), with one exception. CS2/N-methylpyridone was found to be a better solvent than CS2/(I). The results suggest that solvents which have similar basicities, but have a more flattened shape, such as aromatic rings compared to saturated rings, are better extraction agents. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Dyrkacz, GR (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 31 TC 15 Z9 18 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD NOV-DEC PY 2001 VL 15 IS 6 BP 1409 EP 1413 DI 10.1021/ef010036s PG 5 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 495HM UT WOS:000172334500011 ER PT J AU Tomczyk, NA Winans, RE Shinn, JH Robinson, RC AF Tomczyk, NA Winans, RE Shinn, JH Robinson, RC TI On the nature and origin of acidic species in petroleum. 1. Detailed acid type distribution in a California crude oil SO ENERGY & FUELS LA English DT Article ID MASS-SPECTROMETRY; NAPHTHENIC ACIDS; AMINO-ACIDS; GEOCHEMISTRY; SEDIMENTS AB Acidity in crude oils has long been a problem for refining. Knowledge of the detailed chemical composition of the acids responsible for corrosion can facilitate identification of problem crude oils and potentially lead to improved processing options for corrosive oils. A highly aerobically biodegraded crude from the San Joaquin Valley, which has a long history of causing corrosion problems during refining was the subject of this study. The oil was first extracted with base, then acidified and extracted with petroleum ether. A portion of the resulting acid fraction was methylated. The unmethylated extract was analyzed by FTIR, NMR, and the methylated sample was analyzed by high-resolution mass spectrometry (HRMS). Over 96% of the ions observed in HRMS have been assigned reliable formulas. Considerably greater functionality is seen in this sample than would be presumed from the "naphthenic acid" title typically assigned to these species. Although over 60% of the compounds contained two or more oxygens, compounds containing only oxygen heteroatoms accounted for less than 10% of the acidic compounds identified. Approximately one-half of the species contained nitrogen and about one-fourth contained sulfur. It is believed that microbial degradation is a major source of these acidic components. It was also observed that acid species with higher degrees of heteroatom substitution generally also had a higher degree of saturation than those species having less heteroatoms, possibly due to impeded migration of highly substituted, less-saturated species. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Chevron Res & Technol Co, Richmond, CA 94802 USA. RP Winans, RE (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. EM rewinans@anl.gov NR 19 TC 86 Z9 93 U1 1 U2 30 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD NOV-DEC PY 2001 VL 15 IS 6 BP 1498 EP 1504 DI 10.1021/ef010106v PG 7 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA 495HM UT WOS:000172334500024 ER PT J AU Plotkin, SE AF Plotkin, SE TI European and Japanese fuel economy initiatives: what they are, their prospects for success, their usefulness as a guide for US action SO ENERGY POLICY LA English DT Article DE automobiles; fuel economy; energy efficiency policy AB The new Japanese weight class standards for fuel economy and European Voluntary Commitment for reducing carbon emissions, both aimed at light-duty vehicles, are likely to further separate the fuel efficiency of the Japanese and European fleets from the US fleet.... and they may put substantial pressure on both US manufacturers and the federal government to take action to narrow the growing fuel economy gap. This paper describes these two new initiatives, discusses some concerns with their outcome, and provides some insight into their potential applicability to the United States market. In particular, the paper compares the regulatory conditions governing fuel economy (test regimes, emissions standards) and the differences in the cost-effectiveness of new fuel economy technology (given differences in fuel prices, vehicle taxation, and other factors affecting technology cost/fuel savings tradeoffs) for the three markets. European and Japanese market conditions are more conducive to improving fuel economy because of less stringent emissions standards (that make direct injection engines more feasible and will likely allow better performance from them) and much higher fuel prices than in the US. However, factors such as high vehicle taxes and, in some European countries, a high percentage of company cars may narrow the gap between the US market and the European market. And very high rates of driving in the US also enhance the cost-effectiveness of efficiency technologies (C) 2001 Published by Elsevier Science Ltd. C1 Argonne Natl Lab, Washington, DC 20024 USA. RP Plotkin, SE (reprint author), Argonne Natl Lab, 955 Enfant Plaza SW, Washington, DC 20024 USA. NR 11 TC 22 Z9 22 U1 0 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 13 BP 1073 EP 1084 DI 10.1016/S0301-4215(01)00051-9 PG 12 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 475PC UT WOS:000171172300002 ER PT J AU Wiser, RH Fowlie, M Holt, EA AF Wiser, RH Fowlie, M Holt, EA TI Public goods and private interests: understanding non-residential demand for green power SO ENERGY POLICY LA English DT Article DE green power; renewable energy; customer choice ID VOLUNTARY OVERCOMPLIANCE; INFORMATION; BEHAVIOR; MODEL AB This article presents the results of the first large-scale mail survey of non-residential green power customers in the United States. The survey explored the motivations, attitudes, and experiences of 464 business, non-profit, and public-sector customers that have voluntarily opted to purchase-and frequently pay a premium for-renewable electricity. Particular attention in this article is paid to the motivations of these organizations in purchasing renewable electricity, and our findings are compared to the extant literature on the motivations of firms to voluntarily exceed environmental regulations. Perhaps the most interesting contribution of this research comes in its demonstration of the importance of "altruism" as a motivator in non-residential green power purchases among early adopters. This finding, and the further discovery that the principal non-altruistic motivation for purchasing green power is employee morale, differs substantially from the predictions of the extant literature. Results of this study should be of value to marketers trying to meet the needs of non-residential customers, to policymakers interested in fostering and understanding nonresidential demand for green power, and to academics pondering the motivations for firms to engage in such voluntary environmental initiatives. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Ed Holt & Associates Inc, Harpswell, ME 04079 USA. RP Wiser, RH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, 1 Cyclotron Rd,MS 90-4000, Berkeley, CA 94720 USA. NR 33 TC 28 Z9 28 U1 3 U2 11 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 13 BP 1085 EP 1097 DI 10.1016/S0301-4215(01)00053-2 PG 13 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 475PC UT WOS:000171172300003 ER PT J AU Brown, MA Short, W Levine, MD AF Brown, MA Short, W Levine, MD TI Special issue - Scenarios for a clean energy future SO ENERGY POLICY LA English DT Editorial Material C1 Oak Ridge Natl Lab, Energy Efficiency & Renewable Energy Program, Oak Ridge, TN 37831 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Brown, MA (reprint author), Oak Ridge Natl Lab, Energy Efficiency & Renewable Energy Program, POB 2008,Bethel Valley Rd,Bldg 4500N,MS-6186, Oak Ridge, TN 37831 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1177 EP 1177 DI 10.1016/S0301-4215(01)00102-1 PG 1 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400001 ER PT J AU Brown, MA Levine, MD Short, W Koomey, JG AF Brown, MA Levine, MD Short, W Koomey, JG TI Scenarios for a clean energy future SO ENERGY POLICY LA English DT Article DE clean energy; climate change; carbon trading AB This paper summarizes the results of a study-Scenarios for a Clean Energy Future-that assess how energy-efficient and clean energy technologies can address key energy and environmental challenges facing the US. A particular focus of this study is the energy, environmental, and economic impacts of different public policies and programs. Hundreds of technologies and approximately 50 policies are analyzed. The study concludes that policies exist that can significantly reduce oil dependence, air pollution, carbon emissions, and inefficiencies in energy production and end-use systems at essentially no net cost to the US economy. The most advanced scenario finds that by the year 2010, the US could bring its carbon dioxide emissions three-quarters of the way back to 1990 levels. The study also concludes that over time energy bill savings in these scenarios can pay for the investments needed to achieve these reductions in energy use and associated greenhouse gas emissions. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Energy Efficiency & Renewable Energy Program, Oak Ridge, TN 37831 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Brown, MA (reprint author), Oak Ridge Natl Lab, Energy Efficiency & Renewable Energy Program, POB 2008, Oak Ridge, TN 37831 USA. NR 33 TC 54 Z9 55 U1 1 U2 12 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1179 EP 1196 DI 10.1016/S0301-4215(01)00066-0 PG 18 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400002 ER PT J AU Brown, MA AF Brown, MA TI Market failures and barriers as a basis for clean energy policies SO ENERGY POLICY LA English DT Article DE market failures; efficiency gap; clean energy ID DISCOUNT RATES; EFFICIENCY GAP; CONSERVATION; INVESTMENTS AB This paper provides compelling evidence that large-scale market failures and barriers prevent consumers in the United States from obtaining energy services at least cost. Assessments of numerous energy policies and programs suggest that public interventions can overcome many of these market obstacles. By articulating these barriers and reviewing the literature on ways of addressing them, this paper provides a strong justification for the policy portfolios that define the "Scenarios for a Clean Energy Future," a study conducted by five National Laboratories. These scenarios are described in other papers published in this special issue of Energy Policy. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Energy Efficiency & Renewable Energy Program, Oak Ridge, TN 37831 USA. RP Brown, MA (reprint author), Oak Ridge Natl Lab, Energy Efficiency & Renewable Energy Program, POB 2008, Oak Ridge, TN 37831 USA. NR 57 TC 150 Z9 150 U1 3 U2 26 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1197 EP 1207 DI 10.1016/S0301-4215(01)00067-2 PG 11 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400003 ER PT J AU Koomey, JG Webber, CA Atkinson, CS Nicholls, A AF Koomey, JG Webber, CA Atkinson, CS Nicholls, A TI Addressing energy-related challenges for the US buildings sector: results from the clean energy futures study SO ENERGY POLICY LA English DT Article DE energy efficiency in buildings; carbon reductions; energy scenarios ID DISCOUNT RATES; EFFICIENCY; BARRIERS; INVESTMENTS; POLICY AB This article presents dollar, energy, and carbon savings associated with adoption of more energy-efficient technologies in the buildings sector for two policy scenarios that represent departures from business-as-usual (BAU) case assumptions. Both scenarios result in net savings in the total cost of providing energy services relative to the BAU case (accounting for fuel expenditures and the direct incremental costs of efficiency programs and investments in the scenario), while still saving energy and reducing carbon emissions. Primary energy savings for the building sector are about 18% in the advanced scenario in 2020 relative to the BAU case. Total carbon savings in that year, including both demand and supply side effects, are almost 40% of BAU emissions. These savings reduce carbon emissions from this sector to below 1990 levels by 2020. Published by Elsevier Science Ltd. C1 LBNL, Berkeley, CA 94720 USA. Pacific NW Natl Lab, PNNL, Washington, DC 20024 USA. RP Koomey, JG (reprint author), LBNL, 1 Cyclotron Rd,Bldg 90-4000, Berkeley, CA 94720 USA. NR 36 TC 16 Z9 16 U1 1 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1209 EP 1221 DI 10.1016/S0301-4215(01)00068-4 PG 13 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400004 ER PT J AU Worrell, E Price, L AF Worrell, E Price, L TI Policy scenarios for energy efficiency improvement in industry SO ENERGY POLICY LA English DT Article DE energy efficiency; industry; policies; modeling ID BARRIERS; CONSERVATION; INVESTMENTS; EMISSIONS AB We have investigated three policy scenarios, entailing different degrees of commitment to improve energy efficiency to address the energy, economic and environmental challenges faced by the US industry. The scenarios reflect alternative views of the urgency with which policymakers and the American people will view these challenges and the policies they will seek. The industry consumes about 37% of primary energy in the United States, and is expected to grow under business-as-usual conditions. The policy scenarios find energy efficiency improvements from 7% to 17% beyond business as usual by 2020 for the Moderate and Advanced scenarios, respectively. The study demonstrates that there are substantial potentials for further efficiency improvement in the industry. However, an integrated policy framework that accounts for the different characteristics of industrial sector decision-makers, technologies and sectors is needed to achieve these potentials. Published by Elsevier Science Ltd. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Worrell, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Environm Energy Technol Div, MS 90-4000,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Worrell, Ernst/L-5455-2013 OI Worrell, Ernst/0000-0002-0199-9755 NR 54 TC 18 Z9 18 U1 1 U2 9 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1223 EP 1241 DI 10.1016/S0301-4215(01)00069-6 PG 19 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400005 ER PT J AU Greene, DL Plotkin, SE AF Greene, DL Plotkin, SE TI Energy futures for the US transport sector SO ENERGY POLICY LA English DT Article DE transportation; energy efficiency; advanced technology AB This paper explores how advanced transportation technologies and alternative fuels, together with policies aimed at reducing greenhouse emissions and energy use, can help address the energy challenges facing the US transportation system over the coming decades. Three scenarios of future transportation energy use are constructed to represent alternative views of the urgency with which the federal government and the American people will view these challenges, and the policy interventions they will seek. The analysis concludes, first, that US transportation energy use and greenhouse emissions will increase virtually unchecked without policy intervention or unforeseen large, long-lasting fuel price increases, and second, that policies that stimulate technology development and deployment can substantially slow this growth-though not without a considerable time lag due to the slow turnover of the vehicle fleet and limits on the rate of technology development and deployment. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Natl Transportat Res Ctr, Knoxville, TN 37932 USA. Argonne Natl Lab, Washington, DC 20024 USA. RP Greene, DL (reprint author), Oak Ridge Natl Lab, Natl Transportat Res Ctr, 2360 Cherahala Blvd, Knoxville, TN 37932 USA. NR 12 TC 26 Z9 27 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1255 EP 1270 DI 10.1016/S0301-4215(01)00071-4 PG 16 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400007 ER PT J AU Southworth, F AF Southworth, F TI On the potential impacts of land use change policies on automobile vehicle miles of travel SO ENERGY POLICY LA English DT Article AB Recent US traffic growth is summarized and its causes discussed, emphasizing the complex causal linkages between automobile travel and the underlying land use patterns that shape it. This causal framework is used to frame a discussion of how the demands for vehicle travel might be reduced through suitable land use impacting policy instruments. This includes instruments that alter the location, mix and intensity of traffic generating and attracting land use, as well as instruments that affect land development through the supply of added transportation capacity. The existing scientific evidence for the effects of land development patterns on aggregate vehicle miles of travel is found to be of limited use at the present time. For the most part this results from past data limitations and because of the variety of both spatial and temporal scales across which such data needs to be collected and analyzed. It is also concluded that successful travel reduction policies are likely to evolve as part of a broader public policy debate over quality of life issues, notably those involving "urban sprawl" and the balance of economic development against environmental sustainability. The full costs of expanding while also maintaining the current automobile dominated transportation infrastructure may also provide an economic rationale for change. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Ctr Transportat Anal, Energy Efficiency & Renewable Program, Oak Ridge, TN 37831 USA. RP Southworth, F (reprint author), Oak Ridge Natl Lab, Ctr Transportat Anal, Energy Efficiency & Renewable Program, POB 2008,Bethel Valley Rd,Bldg 4500N,MS-6186, Oak Ridge, TN 37831 USA. NR 50 TC 11 Z9 13 U1 0 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1271 EP 1283 DI 10.1016/S0301-4215(01)00072-6 PG 13 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400008 ER PT J AU Hadley, SW Short, W AF Hadley, SW Short, W TI Electricity sector analysis in the clean energy futures study SO ENERGY POLICY LA English DT Article DE Greenhouse gas emission reductions; energy efficiency; clean energy technologies; electricity AB This paper examines the impact of policies to reduce carbon and other air emissions in the electric sector. The analysis is from a recent scenario development effort, Scenarios for a Clean Energy Future (CEF), by five National Laboratories. The CEF assesses how policies can be used to promote energy-efficient and clean energy technologies to address key energy and environmental challenges facing the United States. The impact of policies in the electric sector is evaluated using the CEF-NEMS model, which is derived from the National Energy Modeling System (NEMS) model developed by the DOE Energy Information Administration. The analysis shows that by 2020 under the policies analyzed, CO2 and other emissions can be substantially reduced by moving from coal to advanced gas combined cycle systems and renewable energy. Prices show little change and may drop due to decreased end-use demands. Published by Elsevier Science Ltd. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Natl Renewable Energy Lab, Golden, CO USA. RP Hadley, SW (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Hadley, Stanton/O-1465-2015 OI Hadley, Stanton/0000-0002-6514-8802 NR 15 TC 17 Z9 20 U1 0 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1285 EP 1298 DI 10.1016/S0301-4215(01)00073-8 PG 14 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400009 ER PT J AU Sanstad, AH DeCanio, SJ Boyd, GA Koomey, JG AF Sanstad, AH DeCanio, SJ Boyd, GA Koomey, JG TI Estimating bounds on the economy-wide effects of the CEF policy scenarios SO ENERGY POLICY LA English DT Article DE energy efficiency; production possibilities frontier; general equilibrium and macroeconomic effects ID ENERGY EFFICIENCY; CARBON EMISSIONS; BARRIERS; PRODUCTIVITY; INVESTMENTS; PARADOX; MARKETS AB The Scenarios for a Clean Energy Future study relied primarily on "bottom-up" technology-based methods to estimate costs associated with its scenarios. These methods, however, do not allow for calculation of economy-wide or general equilibrium effects of the policies considered. We propose and apply a means of combining the bottom-up estimates with estimates of the costs associated with a carbon charge obtained from computable general equilibrium models. Our approach is based on the concept of production inefficiency: the economy lies within its production frontier with respect to the provision of energy services. The CEF technology policies are interpreted as moving the economy toward its frontier as well as moving the frontier outward, while the carbon charge induces a substitution effect along the frontier. This perspective allows a synthesis of the two sets of calculations. (C) 2001 Published by Elsevier Science Ltd. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Santa Barbara, Dept Econ, Santa Barbara, CA 93106 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Sanstad, AH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 53 TC 15 Z9 15 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1299 EP 1311 DI 10.1016/S0301-4215(01)00074-X PG 13 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400010 ER PT J AU Gumerman, E Koomey, JG Brown, MA AF Gumerman, E Koomey, JG Brown, MA TI Strategies for cost-effective carbon reductions: a sensitivity analysis of alternative scenarios SO ENERGY POLICY LA English DT Article DE sensitivity analysis; energy policy; carbon emissions ID ENERGY-EFFICIENCY; INVESTMENTS; EMISSIONS; BARRIERS; MARKETS AB Analyses of alternative futures often present results for a limited set of scenarios, with little, if any, sensitivity analysis to identify the factors affecting the scenario results. This approach creates an artificial impression of certainty associated with the scenarios considered, and inhibits understanding of the underlying forces. This paper summarizes the economic and carbon savings sensitivity analysis completed for the Scenarios for a Clean Energy Future study (Interlaboratory Working Group, 2000). Its 19 sensitivity cases provide insight into the costs and carbon-reduction impacts of a carbon permit trading system, demand-side efficiency programs, and supply-side policies. Impacts under different natural gas and oil price trajectories are also examined. The results provide compelling evidence that policy opportunities exist in the United States to reduce carbon emissions and save society money. Published by Elsevier Science Ltd. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Oak Ridge Natl Lab, Energy Efficiency & Renewable Energy Program, Oak Ridge, TN 37831 USA. RP Gumerman, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, MS 90-4000,1 Cyclotran Rd, Berkeley, CA 94720 USA. NR 28 TC 6 Z9 6 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD NOV PY 2001 VL 29 IS 14 SI SI BP 1313 EP 1323 DI 10.1016/S0301-4215(01)00075-1 PG 11 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 476PR UT WOS:000171238400011 ER PT J AU Kim, J Corapcioglu, MY AF Kim, J Corapcioglu, MY TI Sharp interface modeling of LNAPL spreading and migration on the water table SO ENVIRONMENTAL ENGINEERING SCIENCE LA English DT Article DE LNAPL; modeling; sharp interface ID FREE PRODUCT RECOVERY; CONTAMINATED AQUIFERS; REMEDIATION AB A common problem associated with subsurface contamination is the leaking of light nonaqueous phase liquids (LNAPLs) such as gasoline from underground storage tanks and other facilities. A model developed by Corapcioglu et al. (1996) to describe LNAPL transport on the water table was solved numerically, by accounting for residual NAPL retained by capillary forces. The model was exercised to simulate LNAPL mound formation and migration Of an established mound. The results show that the ambient groundwater velocity has major effects on both the formation and migration of LNAPL mounds, although the degree of residual saturation affected only migration. Model results provide distributions of the NAPL phase and contaminated soil. The model and the solution method developed in this study can be used as a screening tool to assess the impact of NAPL contamination and to estimate remediation costs. C1 Texas A&M Univ, Dept Civil Engn, College Stn, TX 77843 USA. RP Kim, J (reprint author), Lawrence Berkeley Natl Lab, Div Earth Sci, 1 Cyclotron Rd,MS 90-1116, Berkeley, CA 94720 USA. NR 14 TC 3 Z9 3 U1 5 U2 7 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1092-8758 J9 ENVIRON ENG SCI JI Environ. Eng. Sci. PD NOV-DEC PY 2001 VL 18 IS 6 BP 359 EP 367 DI 10.1089/109287501753359591 PG 9 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 505WT UT WOS:000172939100004 ER PT J AU van der Lelie, D Schwitzguebel, JP Glass, DJ Vangronsveld, J Baker, A AF van der Lelie, D Schwitzguebel, JP Glass, DJ Vangronsveld, J Baker, A TI Assessing phytoremediation's progress in the United States and Europe SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID CONTAMINATED SOILS; PLANTS; TRANSFORMATION; TNT C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Swiss Fed Inst Technol, Lab Environm Biotechnol, Lausanne, Switzerland. Appl PhytoGenet Inc, Athens, GA USA. D Glass Associates, Needham, MA USA. Univ Melbourne, Parkville, Vic 3052, Australia. Limburgs Univ Ctr, Ctr Environm Sci, Diepenbeek, Belgium. RP van der Lelie, D (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 16 TC 48 Z9 53 U1 2 U2 11 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X EI 1520-5851 J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD NOV 1 PY 2001 VL 35 IS 21 BP 446A EP 452A PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 489RZ UT WOS:000172006600016 PM 11718366 ER PT J AU Spalding, BP AF Spalding, BP TI Fixation of radionuclides in soil and minerals by heating SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID SEQUENTIAL EXTRACTION; THERMAL-TREATMENT; METAL BEHAVIOR; FLY-ASH; REMOVAL; RATES; LEAD; BED AB Heating of fine sand-sized common mineral powders (quartz, feldspar, or calcite) or a soil (from the Department of Energy's Hanford site) up to 1000 degreesC, in contact with sorbed radioisotopes (Sr-85, Co-57, Cs-134, or U), markedly increased each isotope's immobilization. A sequential extraction procedure was applied after heating the materials to assess the changes in each isotope's functional form among water-soluble, cation-exchangeable, acid-soluble, and residual phases. The overall immobilization effects were consistent with rapid high temperature ionic diffusion from the initially contaminated surfaces into the mineral matrices; subsequent diffusion out of mineral particles at ambient temperature, as measured by the sequential extraction behavior, would be such a slow process that the radionuclides maybe considered sequestered from further potential environmental mobilization. In the Hanford soil, the effect was found to follow an Arrhenius-type relationship with treatment temperature up to 1000 degreesC for Co-57, Sr-85, and U, and immobilization was independent of previous thermal treatment of the materials. Although Cs-134 exhibited its largest immobilization in the Hanford soil after heating to 1000 degreesC, the large immobilization of Cs-134 at all temperature and even in unheated Hanford soil made it difficult to observe a strong temperature dependence. A general and promising technique for environmental remediation of contaminated soil by high-temperature heating without melting can be extrapolated directly from the empirical leaching information. C1 Oak Ridge Natl Lab, Environm Sci Div, Oak Ridge, TN 37831 USA. RP Spalding, BP (reprint author), Oak Ridge Natl Lab, Environm Sci Div, Oak Ridge, TN 37831 USA. NR 36 TC 8 Z9 11 U1 3 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD NOV 1 PY 2001 VL 35 IS 21 BP 4327 EP 4333 DI 10.1021/es010608n PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 489RZ UT WOS:000172006600042 PM 11718350 ER PT J AU Chang, YJ Hussain, AKMA Stephen, JR Mullen, MD White, DC Peacock, A AF Chang, YJ Hussain, AKMA Stephen, JR Mullen, MD White, DC Peacock, A TI Impact of herbicides on the abundance and structure of indigenous beta-subgroup ammonia-oxidizer communities in soil microcosms SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE herbicide; Nitrosospira; 16S rDNA; population analysis; bioavailability ID 16S RIBOSOMAL-RNA; GRADIENT GEL-ELECTROPHORESIS; MOLECULAR ANALYSIS; GENE-SEQUENCES; NITROSOMONAS-EUROPAEA; CLASS PROTEOBACTERIA; NITRIFYING BACTERIA; MONOOXYGENASE; POPULATIONS; OXIDATION AB In this study, mixtures of five herbicide-formulated products (atrazine, dicamba, fluometuron, metolachlor, and sulfentrazone) were applied to soil microcosm columns in increasing concentrations. The toxic impact of herbicides on the indigenous beta -subclass Proteobacteria autotrophic ammonia-oxidizer (beta -AAO) community was assessed, The beta -AAO population abundances were estimated by competitive polymerase chain reaction (PCR) targeting the gene amoA, encoding the ex-subunit of ammonia monooxygenase. Community structure was examined by PCR and denaturing gradient get electrophoresis targeting 16S rDNA with band excision and sequence analysis, and by analysis of amoA gene fragment clone libraries. The 16S rDNA analyses showed that a single ribotype of Nitrosospira cluster 3 was the dominant beta -AAO in all treatments. At a finer scale, amoA clone library analysis suggested a shift in community structure corresponding to the 100-ppm application. Competitive PCR indicated significant differences between treatments. The control exhibited relatively stable population abundance over the time period examined. The 10-ppm treatment induced a population increase, but a significant decrease was induced by the 100-ppm application. At 1,000 ppm, the ammonia-oxidizer population dropped below the method detection limit by the first sampling point. An impact on ammonia oxidizers resulting front the application of herbicides was observed, both in abundance and community structure. C1 Univ Tennessee, Ctr Biomarker Anal, Knoxville, TN 37932 USA. Hort Res Int, Crop & Weed Sci, Warwick CV35 9EF, England. Univ Tennessee, Dept Plant & Soil Sci, Knoxville, TN 37932 USA. Oak Ridge Natl Lab, Div Biol Sci, Oak Ridge, TN 37831 USA. RP Chang, YJ (reprint author), Univ Tennessee, Ctr Biomarker Anal, Knoxville, TN 37932 USA. NR 40 TC 43 Z9 45 U1 1 U2 13 PU SETAC PI PENSACOLA PA 1010 NORTH 12TH AVE, PENSACOLA, FL 32501-3367 USA SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD NOV PY 2001 VL 20 IS 11 BP 2462 EP 2468 DI 10.1897/1551-5028(2001)020<2462:IOHOTA>2.0.CO;2 PG 7 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 504RY UT WOS:000172870700010 PM 11699770 ER PT J AU Efroymson, RA Sample, BE Suter, GW AF Efroymson, RA Sample, BE Suter, GW TI Uptake of inorganic chemicals from soil by plant leaves: Regressions of field data SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE bioaccumulation; plant uptake; exposure; metal; ecological risk assessment ID CONTAMINATED SOILS; APPLIED SELENIUM; HEAVY-METALS; CADMIUM; LEAD; GROWTH; ZINC; CORN; ACCUMULATION; PHOSPHORUS AB The estimation of chemical concentrations in wildlife foods, such as plant foliage, is often performed for risk assessments at contaminated sites. Regression models and uptake factors for use in estimating the uptake of inorganic elements from soil by above-ground plant tissues were derived in this study. These included models for arsenic, cadmium, copper, lead, mercury, nickel, selenium, and zinc. Models were developed using published data from soil contaminated in the field and were validated using measured concentrations from two contaminated sites. Single-variable regression models of log-transformed concentrations in plants versus log-transformed concentrations in soil are generally recommended over simple uptake factors for use in estimating plant uptake of inorganic contaminants in ecological risk assessments, Multiple regression models with soil concentration and pH as the variables are also recommended for estimating the uptake of four chemicals (cadmium, mercury, selenium, and zinc) by plants. Models for use in screening risk assessments, i.e., the upper 95% prediction limits on the regressions, are recommended to provide conservative estimates of uptake of inorganic chemicals by plants. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Efroymson, RA (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. OI Efroymson, Rebecca/0000-0002-3190-880X NR 46 TC 40 Z9 46 U1 2 U2 16 PU SETAC PI PENSACOLA PA 1010 NORTH 12TH AVE, PENSACOLA, FL 32501-3367 USA SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD NOV PY 2001 VL 20 IS 11 BP 2561 EP 2571 DI 10.1897/1551-5028(2001)020<2561:UOICFS>2.0.CO;2 PG 11 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 504RY UT WOS:000172870700023 PM 11699783 ER PT J AU Silbiger, RN Leonard, AC Dimsoski, P Fore, S Guttman, SI Roth, AC Gordon, DA Wessendarp, T Toth, GP Smith, MK AF Silbiger, RN Leonard, AC Dimsoski, P Fore, S Guttman, SI Roth, AC Gordon, DA Wessendarp, T Toth, GP Smith, MK TI Use of molecular markers to study the effects of environmental impacts on genetic diversity in brown bullhead (Ameirus nebulosus) populations SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Article DE highly variable number tandem repeats; randomly amplified polymorphic DNA; allozyme; biological indicator; genetic diversity ID GREAT-LAKES; INBREEDING DEPRESSION; ALLOZYME GENOTYPES; SIMILARITY INDEX; DNA; CONSERVATION; FISH; ECOTOXICOLOGY; FINGERPRINTS; SYSTEMATICS AB Conservation biology needs sound biological information in order to maintain biological diversity in the face of the current rate of loss. An important component of the information needed is the level of genetic diversity within and between populations, especially for those species faced with exposure to environmental stressors. We applied multilocus DNA profile analysis (highly variable number tandem repeats [HVNTR] and randomly amplified polymorphic DNA [RAPD] techniques) and allozyme analysis to test whether individuals from historically degraded sites display levels of genetic diversity different from individuals taken from reference sites. Four Lake Erie tributaries, two impacted and two reference sites, were the sources of brown bullhead (Ameiurus nebulosus) samples. Pairwise comparison of the sampled populations demonstrated an association of decreased genetic diversity with exposure of brown bullhead to stressors using both RAPD and HVNTR analysis. C1 Miami Univ, Dept Zool, Oxford, OH 45056 USA. US EPA, Oak Ridge Inst Sci & Educ, Cincinnati, OH 45268 USA. SOBRAN, Dayton, OH 45432 USA. Truman State Univ, Div Sci, Kirksville, MO 63501 USA. RP Guttman, SI (reprint author), Miami Univ, Dept Zool, Oxford, OH 45056 USA. EM guttmasi@muohio.edu NR 65 TC 10 Z9 11 U1 1 U2 8 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0730-7268 EI 1552-8618 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD NOV PY 2001 VL 20 IS 11 BP 2580 EP 2587 DI 10.1897/1551-5028(2001)020<2580:UOMMTS>2.0.CO;2 PG 8 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 504RY UT WOS:000172870700025 PM 11699785 ER PT J AU Cort, JR Mariappan, SVS Kim, CY Park, MS Peat, TS Waldo, GS Terwilliger, TC Kennedy, MA AF Cort, JR Mariappan, SVS Kim, CY Park, MS Peat, TS Waldo, GS Terwilliger, TC Kennedy, MA TI Solution structure of Pyrobaculum aerophilum DsrC, an archaeal homologue of the gamma subunit of dissimilatory sulfite reductase SO EUROPEAN JOURNAL OF BIOCHEMISTRY LA English DT Article DE dissimilatory sulfite reductase; DsrC; helix-turn-helix; NMR; Pyrobaculum aerophilum ID DESULFOVIBRIO-VULGARIS HILDENBOROUGH; COUPLING-CONSTANTS; ARCHAEOGLOBUS-FULGIDUS; RESONANCE ASSIGNMENTS; PROTEIN STRUCTURES; NMR; GENES; SENSITIVITY; SPECTRA; PURIFICATION AB The solution structure of DsrC, an archaeal homologue of the gamma subunit of dissimilatory sulfite reductase, has been determined by NMR spectroscopy. This 12.7-kDa protein from the hyperthermophilic archaeon Pyrobaculum aerophilum adopts a novel fold consisting of an orthogonal helical bundle with a beta hairpin along one side. A portion of the structure resembles the helix-turn-helix DNA-binding motif common in transcriptional regulator proteins. The protein contains two disulfide bonds but remains folded following reduction of the disulfides. DsrC proteins from organisms other than Pyrobaculum species do not contain these disulfide bonds. A conserved cysteine next to the C-terminus, which is not involved in the disulfide bonds, is located on a seven-residue C-terminal arm that is not part of the globular protein and is likely to dynamically sample more than one conformation. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Los Alamos Natl Lab, Los Alamos, NM USA. RP Kennedy, MA (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Terwilliger, Thomas/K-4109-2012; Peat, Thomas/F-9817-2010 OI Terwilliger, Thomas/0000-0001-6384-0320; Peat, Thomas/0000-0002-6488-0831 FU NIGMS NIH HHS [P50-GM62413] NR 47 TC 33 Z9 33 U1 0 U2 5 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0014-2956 J9 EUR J BIOCHEM JI Eur. J. Biochem. PD NOV PY 2001 VL 268 IS 22 BP 5842 EP 5850 DI 10.1046/j.0014-2956.2001.02529.x PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 495LQ UT WOS:000172343000023 PM 11722571 ER PT J AU Bond, DL Clark, DL Donohoe, RJ Gordon, JC Gordon, PL Keogh, DW Scott, BL Tait, CD Watkin, JG AF Bond, DL Clark, DL Donohoe, RJ Gordon, JC Gordon, PL Keogh, DW Scott, BL Tait, CD Watkin, JG TI A model for trivalent actinides in media containing high carbonate concentrations - Structural characterization of the lanthanide tetracarbonate [Co(NH3)(6)][Na(mu-H2O)(H2O)(4)](2)[Ho(CO3)(4)]center dot 4H(2)O SO EUROPEAN JOURNAL OF INORGANIC CHEMISTRY LA English DT Article DE actinides; lanthanides; carbonate; coordination chemistry; structural elucidation ID X-RAY STRUCTURE; COMPLEXES; CRYSTAL AB The identity of the limiting Ho-III species in aqueous solutions with high carbonate concentrations has been determined to be Ho(CO3)(4)(5-). Single crystals of [Co(NH3)(6)][Na(mu -H2O)(H2O)(4)](2)[Ho(CO3)(4)]. 4H(2)O were obtained by the addition of [Co(NH3)(6)](3+) to an aqueous 0.04 m solution of Ho-III in 2.1 M Na2CO3. The asymmetric unit contains the anion, [Ho(CO3)(4)](5-), a [Co(NH3)(6)](3+) cation and two Na+ cations, which are bound to H2O molecules in an edge-sharing bioctahedral geometry. The [Ho(CO3)(4)](5-) anion is eight coordinate with four bidentate carbonate ligands bound to the Ho atom. The molecule has essentially C-2 nu symmetry with two coplanar carbonates making a vane, which is perpendicular to a similar vane produced by the other two carbonate ligands. An alternative way to this view molecule is through the geometry of the C atoms, which are found in a distorted tetrahedron. The average Ho-O distance was determined to be 2.361(5) Angstrom, while the average Ho-C distance was 2.784(6) A. The IR and Raman spectra were determined in both the solid state and solution in order to confirm the solution speciation. The Raman data show a single CO32- stretch for the solid at 1062 cm(-1), The solution data show multiple peaks with the most prominent being at 1048 cm(-1), which is consistent with the literature reports of an equilibrium mixture. The IR data for the solids confirm the X-ray results showing bidentate carbonate ligands by the splitting of the nu (3) band of the CO32-. The crystal data for [Co(NH3)(6)][Na(mu -H2O)(H2O)(4)](2)[Ho(Co-3)(4)]. 4H(2)O are as follows: monoclinic space group P2/n, a = 8.7091(5) Angstrom, b = 10.8744(6) Angstrom, c = 15.7971(9) Angstrom, beta = 93.117(1)degrees, Z = 2, R1 = 0.0307, wR2 = 0.0756. C1 Los Alamos Natl Lab, GT Seaborg Inst Transactinium Sci, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, GT Seaborg Inst Transactinium Sci, Div Chem, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, GT Seaborg Inst Transactinium Sci, Biosci Div, Los Alamos, NM 87545 USA. RP Gordon, JC (reprint author), Los Alamos Natl Lab, GT Seaborg Inst Transactinium Sci, Div Nucl Mat Technol, MS-J514, Los Alamos, NM 87545 USA. RI Clark, David/A-9729-2011; Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 43 TC 8 Z9 8 U1 0 U2 5 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 1434-1948 J9 EUR J INORG CHEM JI Eur. J. Inorg. Chem. PD NOV PY 2001 IS 11 BP 2921 EP 2926 PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 487GM UT WOS:000171865400025 ER PT J AU Vinnik, DV Prozorkevich, AV Smolyansky, SA Toneev, VD Hecht, MB Roberts, CD Schmidt, SM AF Vinnik, DV Prozorkevich, AV Smolyansky, SA Toneev, VD Hecht, MB Roberts, CD Schmidt, SM TI Plasma production and thermalisation in a strong field SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID QUARK-GLUON-PLASMA; HEAVY-ION COLLISIONS; NUCLEUS-NUCLEUS COLLISIONS; PREEQUILIBRIUM EVOLUTION; PARTICLE-PRODUCTION; ELECTRIC-FIELD; PAIR CREATION; MODEL; EQUILIBRATION; HYDRODYNAMICS AB Aspects of the formation and equilibration of a quark-gluon plasma are explored using a quantum kinetic equation, which involves a non-Markovian, Abelian source term for quark and antiquark production and, for the collision term, a relaxation time approximation that defines a time-dependent quasi-equilibrium temperature and collective velocity. The strong Abelian field is determined via the simultaneous solution of Maxwell's equation. A particular feature of this approach is the appearance of plasma oscillations in all thermodynamic observables. Their presence can lead to a sharp increase in the time-integrated dilepton yield, although a rapid expansion of the plasma may eliminate this signal. C1 Univ Tubingen, Inst Theoret Phys, D-72076 Tubingen, Germany. Saratov NG Chernyshevskii State Univ, Dept Phys, Saratov 410071, Russia. Joint Inst Nucl Res, Bogoliubov Lab Theoret Phys, Dubna 141980, Russia. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Vinnik, DV (reprint author), Univ Tubingen, Inst Theoret Phys, Morgenstelle 14, D-72076 Tubingen, Germany. OI Roberts, Craig/0000-0002-2937-1361 NR 44 TC 36 Z9 37 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6044 J9 EUR PHYS J C JI Eur. Phys. J. C PD NOV PY 2001 VL 22 IS 2 BP 341 EP 349 DI 10.1007/s100520100787 PG 9 WC Physics, Particles & Fields SC Physics GA 509WJ UT WOS:000173172500014 ER PT J AU Pumir, A Shraiman, BI Chertkov, M AF Pumir, A Shraiman, BI Chertkov, M TI The Lagrangian view of energy transfer in turbulent flow SO EUROPHYSICS LETTERS LA English DT Article ID SCALAR AB Hydrodynamic turbulence in 3D is characterized by a non-linear transfer of energy from large to small scales. Here, we provide a geometrical view of energy transfer by relating it to the deformation of fluid volumes under Lagrangian dynamics. The energy flux is parametrized in terms of the coarse-grained velocity difference tensor together with the tensor describing the shape of the volume. Our construction provides an interpretation for the non-trivial time dependence of the energy of relative motion within a cloud of Lagrangian particles observed in the direct numerical simulation turbulence. C1 INLN, F-06560 Valbonne, France. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. Los Alamos Natl Lab, Div Theoret, CNLS, Los Alamos, NM 87545 USA. RP Pumir, A (reprint author), INLN, 1361 Route Lucioles, F-06560 Valbonne, France. RI Chertkov, Michael/O-8828-2015 NR 19 TC 30 Z9 30 U1 0 U2 5 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD NOV PY 2001 VL 56 IS 3 BP 379 EP 385 DI 10.1209/epl/i2001-00530-3 PG 7 WC Physics, Multidisciplinary SC Physics GA 487EC UT WOS:000171859800010 ER PT J AU Campisi, J Kim, SH Lim, CS Rubio, M AF Campisi, J Kim, SH Lim, CS Rubio, M TI Cellular senescence, cancer and aging: the telomere connection SO EXPERIMENTAL GERONTOLOGY LA English DT Review DE antagonistic pleiotropy; genomic instability; immortalization; telomerase; telomere binding proteins; telomere structure; tumor suppression ID NORMAL HUMAN FIBROBLASTS; REPLICATIVE LIFE-SPAN; NORMAL HUMAN-CELLS; HUMAN TUMOR-CELLS; EPITHELIAL-CELLS; IN-VIVO; MAMMALIAN TELOMERES; IONIZING-RADIATION; LENGTH REGULATION; MOUSE TELOMERASE AB Telomeres are the repetitive DNA sequences and specialized proteins that form the distinctive structure that caps the ends of linear chromosomes. Telomeres allow cells to distinguish the chromosome ends from double strand DNA breaks. The telomeric structure prevents the degradation or fusion of chromosome ends, and thus is essential for maintaining the integrity and stability of eukaryotic genomes. In addition, and perhaps less widely appreciated, telomeres may also indirectly influence gene expression. The length, structure and organization of telomeres are regulated by a host of telomere-associated proteins, and can be influenced by basic cellular processes such as cell proliferation, differentiation, and DNA damage. In mammalian cells, telomere length and/or telomere structure have been linked to both cancer and aging. Here, we briefly review what is known about mammalian telomeres and the proteins that associate with them, and discuss the cellular and organismal consequences of telomere dysfunction and the evidence that cells with dysfunctional telomeres. can contribute to cancer and aging phenotypes. (C) 2001 Published by Elsevier Science Inc. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Campisi, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Mailstop 84-171,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 120 TC 214 Z9 224 U1 1 U2 21 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0531-5565 J9 EXP GERONTOL JI Exp. Gerontol. PD NOV PY 2001 VL 36 IS 10 BP 1619 EP 1637 DI 10.1016/S0531-5565(01)00160-7 PG 19 WC Geriatrics & Gerontology SC Geriatrics & Gerontology GA 488RM UT WOS:000171949500004 PM 11672984 ER PT J AU Nelson, RA AF Nelson, RA TI Do we doubt too little? Examples from the thermal sciences SO EXPERIMENTAL THERMAL AND FLUID SCIENCE LA English DT Article ID HIGH HEAT-FLUX; WATER; NUCLEATION; SURFACE AB Has the thermal science community continued to question itself? While I do not address this question for all areas of the thermal sciences, I do consider our status in the area of boiling and in particular nucleate boiling. I believe our ability to model through correlation has been very fruitful and will continue to be the basis by which we design and build system into the future. I believe our ability to mechanistically model the nucleate boiling process is only now at a point where we might begin building simulations that can represent the temporal and spatial variations we observe experimentally. To begin what I hope will be a continuing discussion into the future, I propose a framework for modeling and understanding why boiling behaves as it does. Your debate of issues and elements within the framework (doubts about it) is not just expected, it is required if we are to make progress. Published by Elsevier Science Inc. C1 Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. RP Nelson, RA (reprint author), Los Alamos Natl Lab, Div Appl Phys, POB 1663,MS F661, Los Alamos, NM 87545 USA. NR 37 TC 1 Z9 1 U1 1 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0894-1777 J9 EXP THERM FLUID SCI JI Exp. Therm. Fluid Sci. PD NOV PY 2001 VL 25 IS 5 BP 255 EP 267 AR PII S0894-1777(01)00073-5 DI 10.1016/S0894-1777(01)00073-5 PG 13 WC Thermodynamics; Engineering, Mechanical; Physics, Fluids & Plasmas SC Thermodynamics; Engineering; Physics GA 582PU UT WOS:000177361000006 ER PT J AU Mulholland, PJ Fellows, CS Tank, JL Grimm, NB Webster, JR Hamilton, SK Marti, E Ashkenas, L Bowden, WB Dodds, WK McDowell, WH Paul, MJ Peterson, BJ AF Mulholland, PJ Fellows, CS Tank, JL Grimm, NB Webster, JR Hamilton, SK Marti, E Ashkenas, L Bowden, WB Dodds, WK McDowell, WH Paul, MJ Peterson, BJ TI Inter-biome comparison of factors controlling stream metabolism SO FRESHWATER BIOLOGY LA English DT Article DE inter-biome; metabolism; primary production; respiration; stream ID TRANSIENT STORAGE MODEL; OXYGEN CHANGE TECHNIQUE; GRAVEL-BED RIVER; ECOSYSTEM METABOLISM; LEAF DECOMPOSITION; HEADWATER STREAMS; PRIMARY PRODUCERS; SOLUTE TRANSPORT; LIGHT LIMITATION; HYPORHEIC ZONE AB 1. We studied whole-ecosystem metabolism in eight streams from several biomes in North America to identify controls on the rate of stream metabolism over a large geographic range. The streams studied had climates ranging from tropical to cool-temperate and from humid to arid and were all relatively uninfluenced by human disturbances. 2. Rates of gross primary production (GPP), ecosystem respiration (R) and net ecosystem production (NEP) were determined using the open-system, two-station diurnal oxygen change method. 3. Three general patterns in metabolism were evident among streams: (1) relatively high GPP with positive NEP (i.e. net oxygen production) in early afternoon, (2) moderate primary production with a distinct peak in GPP during daylight but negative NEP at all times and (3) little or no evidence of GPP during daylight and a relatively constant and negative NEP over the entire day. 4. Gross primary production was most strongly correlated with photosynthetically active radiation (PAR). A multiple regression model that included log PAR and stream water soluble reactive phosphorus (SRP) concentration explained 90% of the variation in log GPP. 5. Ecosystem respiration was significantly correlated with SRP concentration and size of the transient storage zone and, together, these factors explained 73% of the variation in R. The rate of R was poorly correlated with the rate of GPP. 6. Net ecosystem production was significantly correlated only with PAR, with 53% of the variation in log NEP explained by log PAR. Only Sycamore Creek, a desert stream in Arizona, had positive NEP (GPP: R>1), supporting the idea that streams are generally net sinks rather than net sources of organic matter. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Griffith Univ, Fac Environm Sci, Ctr Catchment & In Stream Res, Nathan, Qld 4111, Australia. Univ Notre Dame, Dept Biol Sci, Notre Dame, IN 46556 USA. Arizona State Univ, Dept Biol, Tempe, AZ USA. Virginia Polytech Inst & State Univ, Dept Biol, Blacksburg, VA 24061 USA. Michigan State Univ, Kellogg Biol Stn, Hickory Corners, MI 49060 USA. CSIC, Ctr Estudis Avancats Blanes, Blanes, Girona, Spain. Oregon State Univ, Dept Fisheries & Wildlife, Corvallis, OR 97331 USA. Landcare Res, Lincoln, New Zealand. Kansas State Univ, Div Biol, Manhattan, KS 66506 USA. Univ New Hampshire, Dept Nat Resources, Durham, NH 03824 USA. Univ Georgia, Inst Ecol, Athens, GA 30602 USA. Marine Biol Lab, Ctr Ecosyst, Woods Hole, MA 02543 USA. US DOE, Div Environm Sci, Off Biol & Environm Res, Washington, DC 20585 USA. RP Mulholland, PJ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. EM mulhollandpj@ornl.gov RI Fellows, Christine/C-1433-2008; McDowell, William/E-9767-2010; Mulholland, Patrick/C-3142-2012; Grimm, Nancy/D-2840-2009; Marti, Eugenia/J-9146-2012; Bowden, William/J-9219-2014; Hamilton, Stephen/N-2979-2014 OI McDowell, William/0000-0002-8739-9047; Grimm, Nancy/0000-0001-9374-660X; Marti, Eugenia/0000-0002-6910-4874; Hamilton, Stephen/0000-0002-4702-9017 NR 54 TC 207 Z9 212 U1 7 U2 109 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0046-5070 EI 1365-2427 J9 FRESHWATER BIOL JI Freshw. Biol. PD NOV PY 2001 VL 46 IS 11 BP 1503 EP 1517 DI 10.1046/j.1365-2427.2001.00773.x PG 15 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 495KY UT WOS:000172341400007 ER PT J AU Matsukawa, T Shioyama, M Shimada, K Takaku, T Neumeyer, C Tsuji-Iio, S Shimada, R AF Matsukawa, T Shioyama, M Shimada, K Takaku, T Neumeyer, C Tsuji-Iio, S Shimada, R TI Application of parallel connected power-MOSFFT element to high current d.c. power supply SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 21st Symposium on Fusion Technology (SOFT-21) CY SEP 11-15, 2000 CL MADRID, SPAIN DE current; MOSFET; spherical torus AB The low aspect ratio spherical torus (ST), which has single turn toroidal field coil, requires the extremely high d.c. current like as 20 MA to energize the coil. Considering the ratings of such extremely high current and low voltage, power-MOSFET element is employed as the switching device for the a.c./d.c. converter of power supply. One of the advantages of power-MOSFET element is low on-state resistances which is to meet the high current and low voltage operation. Recently, the capacity of power-MOSFET element has been increased and its on-state resistance has been decreased, so that the possibility of construction of high current and low voltage a.c./d.c. converter with parallel connected power-MOSFET elements has been growing. With the aim of developing the high current d.c. power supply using power-MOSFET, the basic characteristics of parallel operation with power-MOSFET elements are experimentally investigated. And, the synchronous rectifier type and the bi-directional self commutated type a.c./d.c. converters using parallel connected power-MOSFET elements are proposed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Tokyo Inst Technol, Nucl Reactors Res Lab, Meguro Ku, Tokyo 1528850, Japan. Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki, Japan. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Matsukawa, T (reprint author), Tokyo Inst Technol, Nucl Reactors Res Lab, Meguro Ku, 2-12-1 Ookayama, Tokyo 1528850, Japan. EM matukawa@nr.titech.ac.jp NR 3 TC 9 Z9 9 U1 1 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD NOV PY 2001 VL 58-59 BP 63 EP 67 DI 10.1016/S0920-3796(01)00279-4 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 506UX UT WOS:000172991100012 ER PT J AU Ribeiro, C Akers, R Alladio, F Axon, K Baylor, L Counsell, GF Dowling, J Fielding, S Garzotti, L Gryaznevich, M Han, WE Innocente, P Jenkins, I deKloe, J Martin, R Micozzi, P Sass, B Sykes, A Terranova, D Todd, TN Twynam, P Wakatani, M Walsh, MJ You, S AF Ribeiro, C Akers, R Alladio, F Axon, K Baylor, L Counsell, GF Dowling, J Fielding, S Garzotti, L Gryaznevich, M Han, WE Innocente, P Jenkins, I deKloe, J Martin, R Micozzi, P Sass, B Sykes, A Terranova, D Todd, TN Twynam, P Wakatani, M Walsh, MJ You, S CA NBI Team TI Pellet injection on START and MAST SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 21st Symposium on Fusion Technology (SOFT-21) CY SEP 11-15, 2000 CL MADRID, SPAIN DE START; MAST; pellet ID HIGH-FIELD-SIDE; TOKAMAKS; DRIFT AB Cryogenic pellet injection has been used in START and it is under commissioning for MAST for fuelling and diagnostics. In START NBI, heated plasmas fuelled with deuterium pellets; high normalized density (Greenwald number N-G < 1.1) with good energy confinement time (tau (E)/tau (ITER97)(Eelmf) less than or equal to 1.3) both at high beta (beta (T) less than or equal to 25%, beta (N) less than or equal to 4.9) have been obtained for time scales close to the energy confinement time (similar to tau (E)). In addition, high fuelling efficiency (similar to 100%) have also been simultaneously observed. A complete pellet injection programme is currently under development in MAST, including the commissioning of a eight pellet injector, technical aspects of launching pellets through guide tubes, dedicated diagnostics, and modelling. (C) 2001 Elsevier Science B.V. All rights reserved. C1 UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. ENEA Fusione, EURATOM Assoc, CR Frascati, I-00044 Frascati, Italy. Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37831 USA. Consorzio RFX, I-35127 Padua, Italy. Univ Utrecht, NL-3508 TC Utrecht, Netherlands. Riso Natl Lab, EURATOM, DK-4000 Roskilde, Denmark. Kyoto Univ, Grad Sch Energy Sci, Uji, Japan. Walsh Sci Ltd, Abingdon OX14 3EB, Oxon, England. Univ London Imperial Coll Sci Technol & Med, London, England. RP Ribeiro, C (reprint author), UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. EM celso.ribeiro@ukaea.org.uk RI Innocente, Paolo/G-4381-2013 NR 15 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 EI 1873-7196 J9 FUSION ENG DES JI Fusion Eng. Des. PD NOV PY 2001 VL 58-59 BP 319 EP 324 DI 10.1016/S0920-3796(01)00308-8 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 506UX UT WOS:000172991100054 ER PT J AU Geraud, A Artaud, JF Gros, G Pocheau, C Combs, SK Foust, CR AF Geraud, A Artaud, JF Gros, G Pocheau, C Combs, SK Foust, CR TI Test of an extruder feed system on the Tore Supra centrifugal pellet injector SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 21st Symposium on Fusion Technology (SOFT-21) CY SEP 11-15, 2000 CL MADRID, SPAIN DE Tore Supra; centrifugal pellet injector; Deuterium AB A deuterium ice extruder feed system has been developed by ORNL for adaptation to the existing ORNL Centrifugal Pellet Injector installed on Tore Supra. A detailed assessment of this feed system coupled to the centrifugal launcher has been carried out in a dedicated test bed at Cadarache, to complete and understand the first results obtained at ORNL and to improve them. The results presented in this paper;are related to the study of the pellet trajectory from the deuterium ice cutting to the collection of the accelerated pellets in a guide tube. The overall reliability of the injector has been shown to be very sensitive to deviations in the free flight part of the trajectory, before capture by the rotating launcher. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEA Cadarache, EURATOM Assoc, Dept Rech Fus Controlee, F-13108 St Paul Les Durance, France. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Geraud, A (reprint author), CEA Cadarache, EURATOM Assoc, Dept Rech Fus Controlee, F-13108 St Paul Les Durance, France. EM geraud@drfc.cad.cea.fr RI Artaud, Jean-Francois/G-8480-2011; Artaud, Jean-Francois/J-2068-2012 NR 7 TC 3 Z9 3 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD NOV PY 2001 VL 58-59 BP 337 EP 341 DI 10.1016/S0920-3796(01)00311-8 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 506UX UT WOS:000172991100057 ER PT J AU Combs, SK Baylor, LR Fisher, PW Foust, CR Gouge, MJ Pavarin, D Sakamoto, R Twynam, P Watson, M Yamada, H AF Combs, SK Baylor, LR Fisher, PW Foust, CR Gouge, MJ Pavarin, D Sakamoto, R Twynam, P Watson, M Yamada, H TI ORNL mock-up tests of inside launch pellet injection on JET and LHD SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 21st Symposium on Fusion Technology (SOFT-21) CY SEP 11-15, 2000 CL MADRID, SPAIN DE pellet injection; plasma; Joint European Torus (JET); Large Helical Device (LHD) ID HIGH-FIELD-SIDE AB In experiments on ASDEX-Upgrade and DIII-D tokamaks, the injection of D(2) pellets from the magnetic high-field side of the plasma resulted in deeper pellet penetration and improved fueling efficiency. Based on those successful experiments, fusion researchers at the Joint European Torus and the Large Helical Device decided to implement inside launch pellet injection. These injection schemes require the use of curved guide tubes to route the pellets from the acceleration devices to the inside launch locations, and the pellets are subjected to stresses from centrifugal and impact forces in traversing the tubes. Before the installations on the large experimental fusion devices, mock-ups of the guide tubes were constructed and tested at the Oak Ridge National Laboratory to determine the pellet speed limit for reliable operation without pellet fracturing. In laboratory testing of the mock-ups, it was found that the pellet speed had to be limited to a few hundreds of meters per second for intact pellets. In this paper, the test equipment and experimental results are described. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Padua, CISAS, I-35131 Padua, Italy. Natl Inst Fus Sci, Gifu 50952, Japan. UKAEA, JET Facil, Abingdon OX14 3EA, Oxon, England. RP Combs, SK (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM combssk@ornl.gov RI Sakamoto, Ryuichi/E-7557-2013 OI Sakamoto, Ryuichi/0000-0002-4453-953X NR 10 TC 22 Z9 23 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD NOV PY 2001 VL 58-59 BP 343 EP 347 DI 10.1016/S0920-3796(01)00379-9 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 506UX UT WOS:000172991100058 ER PT J AU Menon, MM Barry, RE Slotwinski, A Kugel, HW Skinner, CH AF Menon, MM Barry, RE Slotwinski, A Kugel, HW Skinner, CH TI Remote metrology, mapping, and motion sensing of plasma facing components using FM coherent laser radar SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 21st Symposium on Fusion Technology (SOFT-21) CY SEP 11-15, 2000 CL MADRID, SPAIN DE remote metrology; plasma facing components; frequency modulated coherent laser radar AB Metrology inside a D/T burning fusion reactor must necessarily be, conducted remotely since the in-vessel environment would be highly radioactive due to neutron activation of the torus walls. A technique based on frequency modulated coherent laser radar (FM CLR) for such remote metrology is described. Since the FM CLR relies on frequency shift to measure distances, the results are largely insensitive to surface reflectance characteristics. Results of measurements in TFTR and NSTX fusion devices using a prototype FM CLR unit, capable of remotely measuring distances (range) up to 22 m with better than 0.1-mm precision, are provided. These results illustrate that the FM CLR can be used for precision remote metrology as weld as viewing,. It is also shown that by conducting Doppler corrected range measurements using the CLR, the motion of objects can be tracked. Thus, the FM CLR has the potential to remotely measure the motion of plasma facing components (PFCs) during plasma disruptions. Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. MetricVision, Newington, VA 22122 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Menon, MM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM menonmm@ornl.gov NR 2 TC 10 Z9 10 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD NOV PY 2001 VL 58-59 BP 495 EP 498 DI 10.1016/S0920-3796(01)00247-2 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 506UX UT WOS:000172991100084 ER PT J AU Raffray, AR El-Guebaly, L Gordeev, S Malang, S Mogahed, E Najmabadi, F Sviatoslavsky, I Sze, DK Tillack, MS Wang, X AF Raffray, AR El-Guebaly, L Gordeev, S Malang, S Mogahed, E Najmabadi, F Sviatoslavsky, I Sze, DK Tillack, MS Wang, X CA ARIES Team TI High performance blanket for ARIES-AT power plant SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 21st Symposium on Fusion Technology (SOFT-21) CY SEP 11-15, 2000 CL MADRID, SPAIN DE ARIES-AT power plant; safety features; Pb-17Li AB The ARIES-AT blanket has been developed with the overall objective of achieving high performance while maintaining attractive safety features, simple design geometry, credible maintenance and fabrication processes, and reasonable design margins as an indication of reliability. The design is based on Pb-17Li as breeder and coolant and SiC(f)/SiC composite as structural material. This paper summarizes the results of the design study of this blanket. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Wisconsin, Madison, WI 53706 USA. Forschungszentrum Karlsruhe, D-76021 Karlsruhe, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. RP Raffray, AR (reprint author), Univ Calif San Diego, 460 EBU-2, La Jolla, CA 92093 USA. EM raffray@fusion.ucsd.edu NR 8 TC 37 Z9 37 U1 2 U2 7 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD NOV PY 2001 VL 58-59 BP 549 EP 553 DI 10.1016/S0920-3796(01)00493-8 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 506UX UT WOS:000172991100093 ER PT J AU Thome, RJ Heitzenroeder, PJ AF Thome, RJ Heitzenroeder, PJ TI Engineering features of the fusion ignition research experiment (FIRE) SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 21st Symposium on Fusion Technology (SOFT-21) CY SEP 11-15, 2000 CL MADRID, SPAIN DE engineering features; fusion ignition research experiment; tokamak AB The fusion ignition research experiment (FIRE) tokamak is an option for the next step in the US magnetic fusion energy program. It has a major radius of 2 m, and a minor radius of 0.525 m. The general requirements for FIRE are B(T) = 10 T; I(P) = 6.5 MA; minimum flat top time = 10 s, and maximum number of full-power, full-field pulses = 3000 with 30000 pulses at 2/3 full field. The baseline design is able to meet or exceed these objectives. All magnets are inertially cooled with liquid nitrogen and have the capability for an 18 s flat top at 10 T. The use of BeCu in the inner legs of the toroidal field (TF) coil also allows for a field of 12 T with a pulse length of 12 s. Extended pulse lengths at lower fields (e.g. 214 s at 4 T and 2 MA) will allow FIRE to explore advanced tokamak modes (Physics basis for the Fusion Ignition Research Experiment (FIRE) Plasma Facing Components, in: Twenty-first Symposium on Fusion Technology, Madrid, September, 2000). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Gen Atom, San Diego, CA 92121 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Thome, RJ (reprint author), Gen Atom, 3550 Gen Atom Ct, San Diego, CA 92121 USA. EM thomer@gat.com NR 2 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD NOV PY 2001 VL 58-59 BP 797 EP 801 DI 10.1016/S0920-3796(01)00472-0 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 506UX UT WOS:000172991100135 ER PT J AU Ulrickson, MA Brooks, JN Driemeyer, DE Hassenein, A Kessel, CE Rognlien, T Wesley, JC Meade, DM AF Ulrickson, MA Brooks, JN Driemeyer, DE Hassenein, A Kessel, CE Rognlien, T Wesley, JC Meade, DM TI Physics basis for the fusion ignition research experiment plasma facing components SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 21st Symposium on Fusion Technology (SOFT-21) CY SEP 11-15, 2000 CL MADRID, SPAIN DE fusion ignition research experiment; plasma facing components; heat flux conditions ID REDEPOSITION; DIVERTOR; EROSION AB A design study of a fusion ignition research experiment (FIRE) is underway to investigate and assess near term opportunities for advancing the scientific understanding of self-heated fusion plasmas. The emphasis for the FIRE program is on understanding the behavior of plasmas dominated by alpha heating (Q greater than or equal to 5). Study activities have focused on the technical evaluation of a compact, high field, highly shaped tokamak. One of the key issues for the design is to find suitable plasma facing components (PFCs). We have investigated a variety of plasma edge and divertor conditions ranging from reduced recycling high heat flux conditions (attached) to reduced heat flux detached operation. The inner divertor detaches easily while impurities must be added to the outer divertor to achieve detachment. The outer divertor and private space baffle will have to be actively cooled: The plasma-facing surface of the divertor is tungsten bonded to a CuCrZr heat sink. The remainder of the PFCs are beryllium coated copper attached to the vacuum vessel. Plasma current disruptions impose strong constraints on the design. Appreciable PFC surface melting and evaporation and onset of `plasma shielding' are expected. The forces induced on the PFC due to disruptions determine the size of the attachment of the PFC to the vacuum vessel. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Boeing Corp, St Louis, MO 63166 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Gen Atom Co, San Diego, CA 92186 USA. RP Ulrickson, MA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM maulric@sandia.gov NR 9 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD NOV PY 2001 VL 58-59 BP 907 EP 912 DI 10.1016/S0920-3796(01)00227-7 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 506UX UT WOS:000172991100153 ER PT J AU Gohar, Y AF Gohar, Y TI Fusion solution to dispose of spent nuclear fuel, transuranic elements, and highly enriched uranium SO FUSION ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 21st Symposium on Fusion Technology (SOFT-21) CY SEP 11-15, 2000 CL MADRID, SPAIN DE uranium; spent nuclear fuel; transuranic elements; fusion; transmutations AB The disposal of the nuclear spent fuel, the transuranic elements, and the highly enriched uranium represents a major problem under investigation by the international scientific community to identify the most promising solutions. The investigation of this paper focused on achieving the top rated solution for the problem, the elimination goal, which requires complete elimination for the transuranic elements or the highly enriched uranium, and the long-lived fission products. To achieve this goal, fusion blankets with liquid carrier, molten salts or liquid metal eutectics, for the transuranic elements and the uranium isotopes are utilized. The generated energy from the fusion blankets is used to provide revenue for the system. The long-lived fission products are fabricated into fission product targets for transmutation utilizing the neutron leakage from the fusion blankets. This paper investigated the fusion blanket designs for small fusion devices and the system requirements for such application. The results show that 334 MW of fusion power from D-T plasma for 30 years with an availability factor of 0.75 can dispose of the 70,000 tons of the U.S. inventory of spent nuclear fuel generated up to the year 2015. In addition, this fusion solution eliminates the need for a geological repository site, which is a major advantage. Meanwhile, such utilization of the fusion power will provide an excellent opportunity to develop fusion energy for the future. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Dev Div, Fus Power Program, Argonne, IL 60439 USA. RP Gohar, Y (reprint author), Argonne Natl Lab, Dev Div, Fus Power Program, 9700 S Cass Ave, Argonne, IL 60439 USA. EM gohar@anl.gov NR 3 TC 15 Z9 15 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0920-3796 J9 FUSION ENG DES JI Fusion Eng. Des. PD NOV PY 2001 VL 58-59 BP 1097 EP 1101 DI 10.1016/S0920-3796(01)00558-0 PG 5 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 506UX UT WOS:000172991100187 ER PT J AU Csaki, C Erlich, J Grojean, C AF Csaki, C Erlich, J Grojean, C TI The cosmological constant problem in brane-worlds and gravitational Lorentz violations SO GENERAL RELATIVITY AND GRAVITATION LA English DT Article DE cosmological constant; gravitational wave ID DIMENSIONS; HIERARCHY AB Brane worlds are theories with extra spatial dimensions in which ordinary matter is localized on a (3+1) dimensional submanifold. Such theories could have interesting consequences for particle physics and gravitational physics. In this essay we concentrate on the cosmological constant (CC) problem in the context of brane worlds. We show how extra-dimensional scenarios may violate Lorentz invariance in the gravity sector of the effective 4D theory, while particle physics remains unaffected. In such theories the usual no-go theorems for adjustment of the CC do not apply, and we indicate a possible explanation of the smallness of the CC. Lorentz violating effects would manifest themselves in gravitational waves travelling with a speed different from light, which can be searched for in gravitational wave experiments. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. NR 6 TC 26 Z9 26 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0001-7701 J9 GEN RELAT GRAVIT JI Gen. Relativ. Gravit. PD NOV PY 2001 VL 33 IS 11 BP 1921 EP 1927 DI 10.1023/A:1013094709013 PG 7 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 514KR UT WOS:000173438800001 ER PT J AU Stroschein, SL Bonni, S Wrana, JL Luo, KX AF Stroschein, SL Bonni, S Wrana, JL Luo, KX TI Smad3 recruits the anaphase-promoting complex for ubiquitination and degradation of SnoN SO GENES & DEVELOPMENT LA English DT Article DE SnoN; TGF-beta; Smad proteins; anaphase-promoting complex; ubiquitin; degradation ID PROTEASOME-DEPENDENT DEGRADATION; TGF-BETA; TUMOR-SUPPRESSOR; SIGNAL-TRANSDUCTION; CONJUGATING ENZYME; SKI PROTOONCOGENE; CDNA CLONES; PROTEIN; CYCLIN; ACTIVATION AB Smad proteins mediate transforming growth factor-beta (TGF-beta) signaling to regulate cell growth and differentiation. SnoN is an important negative regulator of TGF-beta signaling that functions to maintain the repressed state of TGF-beta target genes in the absence of ligand. On TGF-beta stimulation, Smad3 and Smad2 translocate into the nucleus and induce a rapid degradation of SnoN, allowing activation of TGF-beta target genes. We show that Smad2- or Sniad3-induced degradation of SnoN requires the ubiquitin-dependent proteasome and can be mediated by the anaphase-promoting complex (APC) and the UbcH5 family of ubiquitin-conjugating enzymes. Smad3 and to a lesser extent, Smad2, interact with both the APC and SnoN, resulting in the recruitment of the APC to SnoN and subsequent ubiquitination of SnoN in a destruction box (D box)-dependent manner. In addition to the D box, efficient ubiquitination and degradation of SnoN also requires the Smad3 binding site in SnoN as well as key lysine residues necessary for ubiquitin attachment. Mutation of either the Smad3 binding site or lysine residues results in stabilization of SnoN and in enhanced antagonism of TGF-beta signaling. Our studies elucidate an important mechanism and pathway for the degradation of SnoN and more importantly, reveal a novel role of the APC in the regulation of TGF-beta signaling. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Mt Sinai Hosp, Samuel Lunenfeld Res Inst, Program Mol Biol & Canc, Toronto, ON M5G 1X5, Canada. RP Luo, KX (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RI Wrana, Jeffrey/F-8857-2013 FU NCI NIH HHS [CA87940, R01 CA087940] NR 68 TC 171 Z9 184 U1 0 U2 2 PU COLD SPRING HARBOR LAB PRESS PI PLAINVIEW PA 1 BUNGTOWN RD, PLAINVIEW, NY 11724 USA SN 0890-9369 J9 GENE DEV JI Genes Dev. PD NOV 1 PY 2001 VL 15 IS 21 BP 2822 EP 2836 PG 15 WC Cell Biology; Developmental Biology; Genetics & Heredity SC Cell Biology; Developmental Biology; Genetics & Heredity GA 489WT UT WOS:000172016000006 PM 11691834 ER PT J AU Staudigel, H Albarede, F Anderson, DL Derry, L McDonough, B Shaw, HF White, W Zindler, A AF Staudigel, H Albarede, F Anderson, DL Derry, L McDonough, B Shaw, HF White, W Zindler, A CA GERM Steering Comm TI Electronic data publication in geochemistry: A plea for "full disclosure" SO GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS LA English DT Article DE databases; data formats; Geochemical Earth Reference Model; geochemistry : instruments and techniques; hydrology : instruments and techniques; mineralogy and petrology : instruments and techniques C1 Univ Calif San Diego 0225, Scripps Inst Oceanog, Inst Geophys & Planetary Phys, La Jolla, CA 92093 USA. Ecole Normale Super Lyon, F-69364 Lyon 7, France. CALTECH, Seismol Lab, Pasadena, CA 91125 USA. Cornell Univ, Dept Geol Sci, Ithaca, NY 14853 USA. Univ Maryland, Dept Geol, College Pk, MD 20742 USA. US DOE, Div Chem Sci Geosci & Biosci, Off Basic Energy Sci, Germantown, MD 20874 USA. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Florida State Univ, Dept Geol Sci, Tallahassee, FL 32306 USA. RP Staudigel, H (reprint author), Univ Calif San Diego 0225, Scripps Inst Oceanog, Inst Geophys & Planetary Phys, La Jolla, CA 92093 USA. RI Shaw, Henry/B-6445-2012; Albarede, Francis/A-8871-2011; White, William/N-3231-2014 OI Shaw, Henry/0000-0003-0681-5430; Albarede, Francis/0000-0003-1994-1428; White, William/0000-0001-9024-7039 NR 0 TC 1 Z9 1 U1 0 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 1525-2027 J9 GEOCHEM GEOPHY GEOSY JI Geochem. Geophys. Geosyst. PD NOV 1 PY 2001 VL 2 BP art. no. EP 2001GC000234 PG 4 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 488EX UT WOS:000171924200002 ER PT J AU Wightman, PG Fein, JB Wesolowski, DJ Phelps, TJ Benezeth, P Palmer, DA AF Wightman, PG Fein, JB Wesolowski, DJ Phelps, TJ Benezeth, P Palmer, DA TI Measurement of bacterial surface protonation constants for two species at elevated temperatures SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID CHEMICAL-EQUILIBRIUM MODEL; SODIUM-CHLORIDE SOLUTIONS; BACILLUS-SUBTILIS; ADSORPTION REACTIONS; ALUMINUM SPECIATION; METAL ADSORPTION; AQUEOUS-SOLUTION; CELL-WALLS; WATER; DISSOLUTION AB This study reports the first potentiometric titrations of bacterial surfaces at elevated temperatures. We used a hydrogen electrode concentration cell to examine the protonation behavior of Bacillus subtilis (an aerobic, gram-positive species present in a wide variety of low-temperature, near-surface environments) at 30, 50, and 75 degreesC. We also investigate the protonation of TOR-39 (an anaerobic, Fe-reducing, thermophylic bacteria isolated from a deep sedimentary basin) at 50 degreesC and compare its Surface properties to those of B. subtilis. Using a surface complexation approach that has been previously applied only to room temperature experiments involving bacteria, we determine the number of functional group types present on each cell wall, their acidity constants, and their site concentrations. We also characterize the temperature dependence of the acidity constants for B.subtilis. Our results indicate that the surface acidity can be successfully described using site-specific reactions involving discrete surface functional groups. Our results indicate that the acidity constants for the surface functional groups on B. subtilis do not change significantly over the temperature interval studied, and that the surface protonation at each temperature can be estimated using a sin-le set of acidity constants and site densities. The best fitting model for B. subtilis is a three- site model with pK(a) values of 4.1, 5.8, and 7.7. Average site abundances for the three dominant functional groups on B. subtilis were determined to be 9.5 (.) 10(-5), 1.0 (.) 10(-4), and 8.8 (.) 10(-5) moles of sites/gm. For TOR-39, the best fitting model was also a 3-site model with pK(a) values of 4.5, 5.8 and 8.2, with site abundances of 6.0 (.) 10(-5), 5.0 (.) 10(-5) and 3.0 (.) 10(-5). This study suggests that bacterial surface site protonation reactions are not strongly temperature dependent, at least to 75 degreesC. The lack of significant temperature dependence could greatly simplify the task of modeling bacteria-water-rock interactions at elevated temperature. Copyright (C) 2001 Elsevier Science Ltd. C1 Univ Notre Dame, Dept Civil Engn & Geol Sci, Notre Dame, IN 46556 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Wightman, PG (reprint author), Univ Notre Dame, Dept Civil Engn & Geol Sci, Notre Dame, IN 46556 USA. RI phelps, tommy/A-5244-2011; BENEZETH, Pascale/H-7969-2014 OI BENEZETH, Pascale/0000-0002-1841-2383 NR 47 TC 26 Z9 26 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD NOV PY 2001 VL 65 IS 21 BP 3657 EP 3669 DI 10.1016/S0016-7037(01)00763-3 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 493LY UT WOS:000172225600004 ER PT J AU Dutrow, BL Travis, BJ Gable, CW Henry, DJ AF Dutrow, BL Travis, BJ Gable, CW Henry, DJ TI Coupled heat and silica transport associated with dike intrusion into sedimentary rock: Effects on isotherm location and permeability evolution SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID DE-FUCA-RIDGE; HYDROTHERMAL SYSTEMS; THERMODYNAMIC PROPERTIES; CONTACT-METAMORPHISM; SKAERGAARD INTRUSION; THERMAL AUREOLES; MASS-TRANSPORT; HIGH-PRESSURES; FLUID-FLOW; CONVECTION AB An 11-meter-wide alkalic monchiquite dike recovered from the subsurface of Louisiana has produced a metasomatic aureole in the adjacent interbedded carbonate mudstones and siltstones. The asymmetric contact aureole, which extends nearly 6 m above and 4 m below the intrusion, contains the metamorphic minerals, diopside, pectolite, fluor-apophyllite, fluorite, and garnet. A series of coupled heat and mass transport calculations was undertaken to provide thermal constraints for the aureole, in the absence of robust geothermometric assemblages, and insights into accompanying mass transport associated with the sedimentary rock-dike system. Calculations were completed for systems with homogeneous, anisotropic, and layered permeability, kappa. Transport, dissolution, and precipitation of silica were also incorporated into calculations. All systems modeled indicate that the thermal pulse waned in similar to3 yr with a return to background temperatures in similar to 10 yr. Heat and fluid transport produce maximum temperature isotherms that are distinctly different in spatial extent and lateral variability for each numerical system. The homogeneous kappa case produced isotherms that pinch and swell vertically above the dike and have large lateral variations, in contrast to the anisotropic kappa case that produced a single large plume above the dike. The layered system kappa case produced the most spatially extensive thermal aureole, unlike that recorded in the rocks. Addition of dissolved silica to the flow system significantly impacts the calculated transport of heat and fluid, primarily due to density changes that affect upwelling dynamics. Although precipitation and dissolution of SiO2 can affect flow through the feedback to permeability, kappa changes were found to be minor for these system conditions. Where kappa decreased, flow was refocused into higher kappa zones, thus mitigating the kappa differences over time. This negative feedback tends to defocus flow and provides a mechanism for lateral migration of plumes. Coupled heat and silica transport produces a complex isotherm geometry surrounding the intrusion due to formation of upwelling and downwelling plumes and lateral translation of plumes, leading to variability in the isotherm pattern that does not reflect the inherent heterogeneity of the initial material properties. Initial heterogeneities in kappa are not a prerequisite for the development of a complicated flow and transport pattern. In addition, if isotherms reflect isograds, these calculations demonstrate that isograds may not form uniform structures with isograd boundaries characterized by their distance from the heat source. Copyright (C) 2001 Elsevier Science Ltd. C1 Louisiana State Univ, Dept Geol & Geophys, Baton Rouge, LA 70803 USA. Los Alamos Natl Lab, Geoanal Grp, Los Alamos, NM 87545 USA. RP Dutrow, BL (reprint author), Louisiana State Univ, Dept Geol & Geophys, Baton Rouge, LA 70803 USA. RI Gable, Carl/B-4689-2011; Henry, Darrell/B-3699-2009; OI Gable, Carl/0000-0001-7063-0815 NR 71 TC 18 Z9 19 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD NOV PY 2001 VL 65 IS 21 BP 3749 EP 3767 DI 10.1016/S0016-7037(01)00704-9 PG 19 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 493LY UT WOS:000172225600010 ER PT J AU Rountree, T AF Rountree, T TI Fundamentals of occupational safety and health SO HEALTH PHYSICS LA English DT Book Review C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Rountree, T (reprint author), Brookhaven Natl Lab, Bldg 701,POB 5000, Upton, NY 11973 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD NOV PY 2001 VL 81 IS 5 BP 592 EP 592 DI 10.1097/00004032-200111000-00015 PG 1 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 484GZ UT WOS:000171683000015 ER PT J AU Musolino, SV AF Musolino, SV TI Building competence in radiation protection and the safe use of radiation sources: Safety guide; safety standards series No. RS-G-1 SO HEALTH PHYSICS LA English DT Book Review C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Musolino, SV (reprint author), Brookhaven Natl Lab, Bldg 701,POB 5000, Upton, NY 11973 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD NOV PY 2001 VL 81 IS 5 BP 593 EP 593 DI 10.1097/00004032-200111000-00019 PG 1 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 484GZ UT WOS:000171683000019 ER PT J AU LePoire, DJ Arnish, JJ Chen, SY Faillace, ER Yuan, YC Schmidt, DW AF LePoire, DJ Arnish, JJ Chen, SY Faillace, ER Yuan, YC Schmidt, DW TI MILDOS uranium milling dose assessment code update SO HEALTH PHYSICS LA English DT Article DE operational topic; mining, uranium; regulations; dose assessment AB The MILDOS-AREA code was developed to estimate radiological doses and risks from uranium milling activities. The code has been used for demonstrating radiological compliance regarding the U.S. Nuclear Regulatory Commission's licensing requirements for uranium milling activities. The code was recently updated with an enhanced software package to address the following four areas: regulatory changes, in-situ leaching extraction technologies, software user interfaces, and software distribution technologies via the Internet. Users can now specify in-situ leaching processes through a Windows object-based Geographic Information System interface with incorporated updated regulation methodologies. The code anti documentation are freely distributed through the Internet. C1 Argonne Natl Lab, Argonne, IL 60439 USA. US Nucl Regulatory Commiss, Rockville, MD USA. Washington Grp Int, Las Vegas, NV USA. RP LePoire, DJ (reprint author), Argonne Natl Lab, 7700 S Cass Ave, Argonne, IL 60439 USA. EM dlepoire@anl.gov NR 13 TC 2 Z9 2 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD NOV PY 2001 VL 81 IS 5 SU S BP S78 EP S84 DI 10.1097/00004032-200111001-00014 PG 7 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 485PD UT WOS:000171762000015 PM 11669198 ER PT J AU Strom, DJ AF Strom, DJ TI Making it safe, making it legal, and creating peace of mind SO HEALTH PHYSICS LA English DT Editorial Material C1 Pacific NW Natl Lab, Risk Anal & Hlth Protect Grp, Richland, WA 99352 USA. Pacific NW Natl Lab, Human Hlth & Safety Tech Network, Richland, WA USA. RP Strom, DJ (reprint author), Pacific NW Natl Lab, Risk Anal & Hlth Protect Grp, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD NOV PY 2001 VL 81 IS 5 SU S BP S46 EP S47 DI 10.1097/00004032-200111001-00002 PG 2 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 485PD UT WOS:000171762000002 PM 11669189 ER PT J AU Lewin, SR Ribeiro, RM Walters, T Lau, GK Bowden, S Locarnini, S Perelson, AS AF Lewin, SR Ribeiro, RM Walters, T Lau, GK Bowden, S Locarnini, S Perelson, AS TI Analysis of hepatitis B viral load decline under potent therapy: Complex decay profiles observed SO HEPATOLOGY LA English DT Article ID QUANTITATIVE RT-PCR; DYNAMICS IN-VIVO; ANTIRETROVIRAL THERAPY; HIV-1 INFECTION; VIRUS-INFECTION; C VIRUS; COMBINATION THERAPY; ADEFOVIR DIPIVOXIL; MOLECULAR BEACONS; TIME AB We used a new real-time polymerase chain reaction (PCR)-based assay that is sensitive, has a wide dynamic linear range, and is highly reproducible to quantify hepatitis B virus (HBV) DNA in the serum of infected individuals undergoing potent antiviral therapy. In addition, we made frequent measurements of viral load after initiation of treatment and maintained follow-up to about 12 weeks. To analyze the data we used a new model of HBV decay, which takes into account that existing drug treatments do not completely block dc novo infection and the possibility of noncytolytic loss of infected cells. On initiation of therapy, there was a mean delay of 1.6 days followed by a biphasic or muliphasic decay of plasma HBV DNA. The slope of the first phase varied considerably, with one individual having rapid decay, corresponding to a virion half-life of I hour, but others showing half-lives of up to 92 hours. Individuals either had a slow second-phase decline (t(1/2) = 7.2 +/- 1.2 days) or a flat second phase. Some individuals exhibited a complex "staircase pattern" of decay, with further phases of viral DNA decline and phases with little change in viral load. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Royal Melbourne Hosp, Victorian Infect Dis Serv, Parkville, Vic 3050, Australia. Royal Melbourne Hosp, Victorian Infect Dis Reference Lab, Parkville, Vic 3050, Australia. Univ Melbourne, Dept Microbiol & Immunol, Parkville, Vic 3052, Australia. Queen Mary Hosp, Dept Med, Hong Kong, Hong Kong, Peoples R China. RP Perelson, AS (reprint author), Los Alamos Natl Lab, Div Theoret, MS-K710, Los Alamos, NM 87545 USA. OI Lewin, Sharon Ruth/0000-0002-0330-8241 FU NCRR NIH HHS [RR06555] NR 37 TC 160 Z9 164 U1 0 U2 2 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0270-9139 J9 HEPATOLOGY JI Hepatology PD NOV PY 2001 VL 34 IS 5 BP 1012 EP 1020 DI 10.1053/jhep.2001.28509 PG 9 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 487HN UT WOS:000171868600019 PM 11679973 ER PT J AU Hu, HM Tai, A Huang, GS Qi, XR Cai, X Chen, JC Dai, YM Wang, ZY Xue, ST Yan, WB Zhou, L Zhao, ZG AF Hu, HM Tai, A Huang, GS Qi, XR Cai, X Chen, JC Dai, YM Wang, ZY Xue, ST Yan, WB Zhou, L Zhao, ZG TI Applications of LUND area law generator in R measurement SO HIGH ENERGY PHYSICS AND NUCLEAR PHYSICS-CHINESE EDITION LA Chinese DT Article DE string fragmentation; hadronization; detection effciency ID FRAGMENTATION AB The well-known Monte Carlo simulation package JETSET is developed to simulate the hadronic final states in e(+) e(-) collision with center-of-mass energy E-cm greater than or similar to 10GeV, but not suitable for few GeV energy region. We develop a Monte Carlo program, LUARLW, which can well simulate two-body up to six-body hadronic final states at BEPC energy region. In LUARLW,the effects of all gluonic emissions are neglected. The LUARLW produces more than 14 distributions, which agree with the BES data very well. This package is used for estimating hadronic events detection efficiencies in the measurements of total cross section of hadron production at, BES between 2-5 GeV. C1 CAS, Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. China Ctr Adv Sci & Technol, Beijing 100080, Peoples R China. Fermi Natl Accelerat Lab, Batavia, IL 60510 USA. Liaoning Univ, Dept Phys, Shenyang 110036, Peoples R China. RP Hu, HM (reprint author), CAS, Inst High Energy Phys, Beijing 100039, Peoples R China. NR 7 TC 10 Z9 10 U1 0 U2 0 PU SCIENCE PRESS PI BEIJING PA 16 DONGHUANGCHENGGEN NORTH ST, BEIJING 100717, PEOPLES R CHINA SN 0254-3052 J9 HIGH ENERG PHYS NUC JI High Energy Phys. Nucl. Phys.-Chin. Ed. PD NOV PY 2001 VL 25 IS 11 BP 1035 EP 1043 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 494CE UT WOS:000172260400001 ER PT J AU Sanzone, DM Tank, JL Meyer, JL Mulholland, PJ Findlay, SEG AF Sanzone, DM Tank, JL Meyer, JL Mulholland, PJ Findlay, SEG TI Microbial incorporation of nitrogen in stream detritus SO HYDROBIOLOGIA LA English DT Article DE chloroform fumigation method; microbial nitrogen; N-15; organic matter; persulfate oxidation; stable isotopes ID N-15 TRACER ADDITION; CHLOROFORM FUMIGATION; SOIL-NITROGEN; FOREST STREAM; EXTRACTION; ISOTOPES; RELEASE AB We adapted the chloroform fumigation method to determine microbial nitrogen (N) and microbial incorporation of N-15 on three common substrates [leaves, wood and fine benthic organic matter (FBOM)] in three forest streams. We compared microbial N and N-15 content of samples collected during a 6-week N-15-NH4 tracer addition in each stream. The N-15 was added during late autumn to Upper Ball Creek, a second-order stream at the Coweeta Hydrologic Lab, North Carolina, U.S.A.; during spring to Walker Branch, a first-order stream on DOE's Oak Ridge National Environmental Research Park, Tennessee; and during summer to Bear Brook, a first-order stream in the Hubbard Brook Experimental Forest, New Hampshire. FBOM was the largest component of organic matter and N standing stock in all streams. Microbial N represented the highest proportion of total N in leaves and least in FBOM in Walker Branch and Bear Brook. In Upper Ball Creek, the proportion of microbial N was higher in FBOM than in used biofilm or on leaves. Standing stock of microbial N on leaves and in FBOM ranged from 37 mg N m(-2) in Bear Brook to 301 mg N m(-2) in Walker Branch. Percent of detrital N in living microbial cells was directly related to total microbial biomass (fungal and bacterial biomass) determined from microscopic counts. partial derivative(15)N values for microbes were generally higher than for bulk detritus, which would result in higher partial derivative(15)N values for animals preferentially consuming or assimilating microbial cells. The proportion of N-15 taken up by detritus during the N-15 experiments that remained in microbial cells by the end of the experiments was highest for wood biofilm in Upper Ball Creek (69%), leaves in Walker Branch (65%) and FBOM in Upper Ball Creek (31%). Lower retention proportions (<1-25%) were observed for other substrates. Our results suggest that microbial cells associated with leaves and wood biofilm were most active in N-15-NH4 immobilization, whereas microbial cells associated with FBOM immobilized little (1)5N from stream water. C1 Univ Georgia, Inst Ecol, Athens, GA 30602 USA. Univ Illinois, Dept Nat Resources & Environm Sci, Urbana, IL USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Inst Ecosyst Studies, Milbrook, NY USA. RP Sanzone, DM (reprint author), Univ Georgia, Inst Ecol, Athens, GA 30602 USA. RI Mulholland, Patrick/C-3142-2012 NR 23 TC 14 Z9 15 U1 0 U2 12 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0018-8158 J9 HYDROBIOLOGIA JI Hydrobiologia PD NOV PY 2001 VL 464 IS 1-3 BP 27 EP 35 DI 10.1023/A:1013930102876 PG 9 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 515TF UT WOS:000173512200004 ER PT J AU Rapaport, A Weichman, L Brickeen, B Green, S Bass, M AF Rapaport, A Weichman, L Brickeen, B Green, S Bass, M TI Laser resonator design using optical ray tracing software: Comparisons with simple analytical models and experimental results SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE cavity resonators; laser resonators; modeling; ray tracing; tolerance analysis AB Software simulation of complex resonator and optical system designs offer the potential to couple traditional opto/mechanical tolerance analysis with the required system performance. One such a software platform, ASAP, and the methodology to perform tolerance analyses has been evaluated and validated for the case of the crossed Porro resonator. Simulation results and experimental measurements are presented and discussed. C1 Univ Cent Florida, CREOL, Sch Opt, Orlando, FL 32816 USA. Sandia Natl Labs, Albuquerque, NM 87123 USA. Honeywell FM&T, Kansas City, MO 64141 USA. RP Rapaport, A (reprint author), Univ Cent Florida, CREOL, Sch Opt, Orlando, FL 32816 USA. NR 3 TC 1 Z9 1 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD NOV PY 2001 VL 37 IS 11 BP 1401 EP 1408 DI 10.1109/3.958355 PG 8 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 483KQ UT WOS:000171634900005 ER PT J AU Rao, HL Steel, MJ Scarmozzino, R Osgood, RM AF Rao, HL Steel, MJ Scarmozzino, R Osgood, RM TI VCSEL design using the bidirectional beam-propagation method SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE bidirectional beam propagation method; laser modes; oxide apertures; vertical-cavity surface-emitting lasers ID VERTICAL-CAVITY LASERS; SURFACE-EMITTING LASERS; TAPERED OXIDE APERTURES; SCATTERING LOSS; PERFORMANCE; SIMULATION AB We present an optical modeling approach for calculating vertical-cavity surface emitting lasers (VCSELs) modes based on the bidirectional beam propagation method. Compared with existing approaches, it is flexible, efficient, and convenient. To demonstrate and validate the approach, we examined several design problems for oxide-confined VCSEL devices. Specifically, we modeled the blue-shift phenomenon in small oxidized VCSELs and compared our calculations with previous results. We also examined the dependence of the threshold gain on different oxide-aperture shaped designs and on the thickness and placement of an aperture layer. C1 Columbia Univ, Microelect Sci Labs, New York, NY 10027 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RSoft Inc, Ossining, NY 10562 USA. RP Rao, HL (reprint author), Columbia Univ, Microelect Sci Labs, New York, NY 10027 USA. RI Steel, Michael/A-1287-2009 OI Steel, Michael/0000-0003-3541-6439 NR 18 TC 16 Z9 16 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD NOV PY 2001 VL 37 IS 11 BP 1435 EP 1440 PG 6 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 483KQ UT WOS:000171634900010 ER PT J AU Baillet, S Mosher, JC Leahy, RM AF Baillet, S Mosher, JC Leahy, RM TI Electromagnetic brain mapping SO IEEE SIGNAL PROCESSING MAGAZINE LA English DT Article ID INVERSE PROBLEM; SOURCE LOCALIZATION; IMAGE-RECONSTRUCTION; ELECTRICAL-ACTIVITY; EVOKED-POTENTIALS; CORTICAL ACTIVITY; VOLUME CONDUCTOR; MEG; EEG; MAGNETOENCEPHALOGRAPHY C1 CNRS, F-75700 Paris, France. Hop La Pitie Salpetriere, Cognit Neurosci & Brain Imaging Lab, F-75651 Paris, France. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ So Calif, Dept Elect Engn Syst, Los Angeles, CA 90089 USA. Univ So Calif, Signal & Image Proc Inst, Los Angeles, CA 90089 USA. RP Baillet, S (reprint author), CNRS, F-75700 Paris, France. RI Magazine, Signal Processing/E-9947-2015 NR 89 TC 673 Z9 686 U1 4 U2 49 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1053-5888 J9 IEEE SIGNAL PROC MAG JI IEEE Signal Process. Mag. PD NOV PY 2001 VL 18 IS 6 BP 14 EP 30 DI 10.1109/79.962275 PG 17 WC Engineering, Electrical & Electronic SC Engineering GA 486VC UT WOS:000171836800005 ER PT J AU Tsap, LV Goldgof, DB Sarkar, S AF Tsap, LV Goldgof, DB Sarkar, S TI Fusion of physically-based registration and deformation modeling for nonrigid motion analysis SO IEEE TRANSACTIONS ON IMAGE PROCESSING LA English DT Article DE corresponding points; deformable models; Hausdorff distance; multiscale methods; nonrigid motion analysis; physically-based vision ID ACTIVE CONTOUR; TAGGED MRI; TRACKING; IMAGES; 2-D AB In our previous work, we used finite element models to determine nonrigid motion parameters and recover unknown local properties of objects given correspondence data recovered with snakes or other tracking models. In this paper, we present a novel multiscale approach to recovery of nonrigid motion from sequences of registered intensity and range images. The main idea of our approach is that a finite element (FEM) model incorporating material properties of the object can naturally handle both registration and deformation modeling using a single model-driving strategy. The method includes a multiscale iterative algorithm based on analysis of the undirected Hausdorff distance to recover correspondences. The method is evaluated with respect to speed and accuracy. Noise sensitivity issues are addressed. Advantages of the proposed approach are demonstrated using man-made elastic materials and human skin motion. Experiments with regular grid features are used for performance comparison with a conventional approach (separate snakes and FEM models). It is shown, however, that the new method does not require a sampling/correspondence template and can adapt the model to available object features. Usefulness of the method is presented not only in the context of tracking and motion analysis, but also for a burn scar detection application. C1 Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. Univ S Florida, Dept Comp Sci & Engn, Tampa, FL 33620 USA. RP Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. EM tsap@llnl.gov; goldgof@csee.usf.edu; sarkar@csee.usf.edu RI Sarkar, Sudeep/A-8213-2009 OI Sarkar, Sudeep/0000-0001-7332-4207 NR 40 TC 13 Z9 13 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1057-7149 EI 1941-0042 J9 IEEE T IMAGE PROCESS JI IEEE Trans. Image Process. PD NOV PY 2001 VL 10 IS 11 BP 1659 EP 1669 DI 10.1109/83.967394 PG 11 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 496FU UT WOS:000172386200007 PM 18255508 ER PT J AU Ashikhmin, A Knill, E AF Ashikhmin, A Knill, E TI Nonbinary quantum stabilizer codes SO IEEE TRANSACTIONS ON INFORMATION THEORY LA English DT Article; Proceedings Paper CT AMS Spring Eastern Section Meeting CY APR 28-29, 2001 CL HOBOKEN, NEW JERSEY SP AMS DE nonbinary quantum codes; quantum stabilizer codes; self-orthogonal codes ID ERROR-CORRECTING CODES AB We define and show how to construct nonbinary quantum stabilizer codes. Our approach is based on nonbinary error bases. It generalizes the relationship between self-orthogonal codes over F-4 and binary quantum codes to one between self-orthogonal codes over F-q2 and q-ary quantum codes for any prime power q. C1 Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Los Alamos Natl Lab, Grp CCS 3, Los Alamos, NM 87545 USA. RP Ashikhmin, A (reprint author), Bell Labs, Lucent Technol, 600 Mt Ave, Murray Hill, NJ 07974 USA. NR 25 TC 169 Z9 184 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9448 J9 IEEE T INFORM THEORY JI IEEE Trans. Inf. Theory PD NOV PY 2001 VL 47 IS 7 BP 3065 EP 3072 DI 10.1109/18.959288 PG 8 WC Computer Science, Information Systems; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 484QD UT WOS:000171700300037 ER PT J AU Melikhov, Y Jiles, DC Tomas, I Lo, CCH Perevertov, O Kadlecova, J AF Melikhov, Y Jiles, DC Tomas, I Lo, CCH Perevertov, O Kadlecova, J TI Investigation of sensitivity of Preisach analysis for nondestructive testing SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article DE Jiles-Atherton model; nondestructive evaluation; Preisach model ID FERROMAGNETIC HYSTERESIS; MODEL AB We applied the Preisach model formalism as a nondestructive material testing method to theoretical systems described by the Jiles-Atherton model. We investigated 1) the influence of stress in the model with magnetomechanical effects on a Preisach-model-based parameter and 2) the sensitivity of the parameter with respect to variation of all the Jiles-Atherton model constants and of the traditional magnetic hysteresis variables. C1 Acad Sci Czech Republ, Inst Phys, Prague 18221, Czech Republic. Iowa State Univ Sci & Technol, Ames Lab, Ctr Nondestruct Evaluat, Ames, IA 50011 USA. RP Melikhov, Y (reprint author), Acad Sci Czech Republ, Inst Phys, Prague 18221, Czech Republic. RI Jiles, David/H-9548-2012; Tomas, Ivan/C-6968-2013; Perevertov, Oleksiy/H-1373-2014 NR 14 TC 5 Z9 6 U1 0 U2 6 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD NOV PY 2001 VL 37 IS 6 BP 3907 EP 3912 DI 10.1109/20.966126 PN 1 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 500YE UT WOS:000172655600007 ER PT J AU Guo, Y Hill, DJ Wang, YY AF Guo, Y Hill, DJ Wang, YY TI Global transient stability and voltage regulation for power systems SO IEEE TRANSACTIONS ON POWER SYSTEMS LA English DT Article DE global nonlinear control; power systems; transient stability; voltage regulation ID H-INFINITY-CONTROL; STABILIZATION; FEEDBACK; DESIGN AB This paper concerns the global control of power systems. It arises from the practical concern that transient stability and voltage regulation are both important properties of power system control, but they are ascribed to different model descriptions and relate to different stages of system operation (i.e., transient period and post-transient period respectively). Earlier control results deal with the two problems separately, or employ a switching strategy of two different kinds of controllers, which causes a discontinuity of system behavior. We design in this paper a global controller to coordinate the transient stabilizer and voltage regulator. The designed controller is smooth and robust with respect to different transient faults. Simulations on a single-machine infinite bus power system have demonstrated better performances compared with existing controllers. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Univ Sydney, Sch Elect & Informat Engn, Sydney, NSW 2006, Australia. Nanyang Technol Univ, Sch Elect & Elect Engn, Singapore 2263, Singapore. RP Guo, Y (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RI Wang, Youyi/A-5040-2011 NR 23 TC 93 Z9 104 U1 1 U2 11 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8950 J9 IEEE T POWER SYST JI IEEE Trans. Power Syst. PD NOV PY 2001 VL 16 IS 4 BP 678 EP 688 DI 10.1109/59.962413 PG 11 WC Engineering, Electrical & Electronic SC Engineering GA 485WT UT WOS:000171787000015 ER PT J AU Cresswell, MW Bonevich, JE Allen, RA Guillaume, NMP Giannuzzi, LA Everist, SC Murabito, CE Shea, PJ Linholm, LW AF Cresswell, MW Bonevich, JE Allen, RA Guillaume, NMP Giannuzzi, LA Everist, SC Murabito, CE Shea, PJ Linholm, LW TI Electrical linewidth test structures patterned in (100) silicon-on-insulator for use as CD standards SO IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING LA English DT Article DE BESOI; cross-bridge resistor; electrical CD; HRTEM; linewidth; SEM; silicon micromachining; silicon-on-insulator; standards; traceability ID MONOCRYSTALLINE FILMS AB Electrical test structures known as cross-bridge resistors have been patterned in (100) epitaxial silicon material that was grown on Bonded and Etched-back Silicon-On-Insulator (BESOT) substrates. The critical dimensions (CDs) of a selection of their reference segments have been measured electrically, by scanning-electron microscopy (SEM), and by lattice-plane counting. The lattice-plane counting is performed on phase-contrast images of the cross sections of the reference segments that are produced by high-resolution transmission-electron microscopy (HRTEM). The reference-segment features were aligned with (110) directions in the BESOT surface material. They were defined by a silicon micromachining process that resulted in their sidewalls being nearly atomically planar and smooth and inclined at 54.737 degrees to the surface (100) plane of the substrate. SEM, HRTEM, and electrical CD (ECD) linewidth measurements have been made on features of various drawn dimensions on the same substrate to investigate the feasibility of a CD traceability path that combines the low cost, robustness, and repeatability of ECD metrology and the absolute measurement of the HRTEM lattice-plane counting technique. Other novel aspects of the (100) silicon-on-insulator (SOI) implementation that are reported here are the ECD test-structure architecture and the making of lattice-plane counts from cross-sectional HRTEM imaging of the reference features. This paper describes the design details and the fabrication of the cross-bridge resistor test structure. The long-term goal is to develop a technique for the determination of the absolute dimensions of the trapezoidal cross sections of the cross-bridge resistors' reference segments, as a prelude to making them available for dimensional reference applications. C1 Natl Inst Stand & Technol, Div Semicond Elect, Gaithersburg, MD 20899 USA. George Washington Univ, Washington, DC 20052 USA. Univ Cent Florida, Orlando, FL 32816 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cresswell, MW (reprint author), Natl Inst Stand & Technol, Div Semicond Elect, Gaithersburg, MD 20899 USA. NR 21 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0894-6507 J9 IEEE T SEMICONDUCT M JI IEEE Trans. Semicond. Manuf. PD NOV PY 2001 VL 14 IS 4 BP 356 EP 364 DI 10.1109/66.964322 PG 9 WC Engineering, Manufacturing; Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 493PD UT WOS:000172231100007 ER PT J AU Mukdadi, OM Datta, SK Telschow, KL Deason, V AF Mukdadi, OM Datta, SK Telschow, KL Deason, V TI Off-axis propagation of ultrasonic guided waves in thin orthotropic layers: Theoretical analysis and dynamic holographic imaging measurement SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article ID LAMB WAVES; ELASTIC-CONSTANTS; LASER GENERATION; THICKNESS DIRECTION; PAPER; PLATES; TRANSDUCERS; VELOCITIES; MODULUS; FILMS AB The elastic properties of many materials in sheet or plate form can be approximated with orthotropic symmetry. In many sheet material manufacturing industries (e.g., the paper industry), manufacturers desire knowledge of certain anisotropic elastic properties in the sheet for handling and quality issues. Ultrasonic wave propagation in plate materials forms a method to determine the anisotropic elastic properties in a nondestructive manner. This work explores exact and approximate analysis methods of ultrasonic guided wave propagation in thin layers, explicitly dealing with orthotropic symmetry and propagation off-axis with respect to the manufacturing direction. Recent advances in full-field ultrasonic imaging methods, based on dynamic holography, allow simultaneous measurement of the plate wave motion in all planar directions within a single image. Results from this laser ultrasonic imaging approach axe presented that record the lowest anti-symmetric (flexural) mode wavefront in a single image without scanning. Specific numerical predictions for flexural wave propagation in two distinctly different types of paper are presented and compared with direct imaging measurements. Very good agreement is obtained for the lowest anti-symmetric plate mode using paper properties independently determined by a third party. Complete determination of the elastic modulus tensor for orthotropic layers requires measurement of other modes in addition to the lowest anti-symmetric. Theoretical predictions are presented for other guided wave modes [extensional (S), flexural (A), and shear-horizontal (SH)] in orthotropic plates with emphasis on propagation in all planar directions. It is shown that there are significant changes in the dispersion characterization of these modes at certain frequencies (including off-axis mode coupling) that can be exploited to measure additional in-plane elastic moduli of thin layers. At present, the sensitivity of the imaging measurement approach limits experimental investigation to relatively large amplitudes easily produced by flexural wave motion (> 0.1 run). Extension of the measurement range and application to other plate wave modes are in progress and shall be reported in future work. C1 Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. EM mukdadi@colorado.edu NR 41 TC 5 Z9 5 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0885-3010 EI 1525-8955 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD NOV PY 2001 VL 48 IS 6 BP 1581 EP 1593 DI 10.1109/58.971710 PG 13 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA 501KR UT WOS:000172684300013 PM 11800121 ER PT J AU Gattiker, JR Wang, JTL Wang, PP AF Gattiker, JR Wang, JTL Wang, PP TI Bioinformatics SO INFORMATION SCIENCES LA English DT Editorial Material C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. New Jersey Inst Technol, Newark, NJ 07102 USA. Duke Univ, Dept Elect & Comp Engn, Durham, NC 27708 USA. RP Gattiker, JR (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0020-0255 J9 INFORM SCIENCES JI Inf. Sci. PD NOV PY 2001 VL 139 IS 1-2 BP 1 EP 2 DI 10.1016/S0020-0255(01)00154-2 PG 2 WC Computer Science, Information Systems SC Computer Science GA 500RV UT WOS:000172641300001 ER PT J AU Critchlow, T Musick, R Slezak, T AF Critchlow, T Musick, R Slezak, T TI Experiences applying meta-data to bioinformatics SO INFORMATION SCIENCES LA English DT Article; Proceedings Paper CT 2nd International Workshop on Biomolecular Informatics CY FEB 27-MAR 03, 2000 CL ATLANTIC CITY, NEW JERSEY ID SEQUENCE AB Bioinformatics is facing the daunting challenge of providing geneticists and biologists effective, efficient access to data currently distributed among dynamic, heterogeneous data sources. Complicating the problem is the speed at which the underlying science and technology evolve, leaving the terminology, databases and interfaces to catch up. As the genomics community moves from sequences to functional genomics, the pressure to find a solution is increasing. Realistically addressing this problem, whether through a data warehouse, multi-database, federated database, or other approach, requires development of an scalable, flexible infrastructure that can quickly adapt to meet user needs in this extremely dynamic environment. This is best accomplished by extensively using meta-data to reduce the application's maintenance costs. Using the DataFoundry project as an example, this paper discusses the first steps and practical problems of developing a meta-data-based infrastructure capable of meeting the demands of an active scientific community. It also demonstrates how much bioinformatics must still progress before it can truly satisfy its users. Published by Elsevier Science Inc. C1 Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Critchlow, T (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, 7000 E Ave,MS L-560, Livermore, CA 94550 USA. NR 17 TC 4 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0020-0255 J9 INFORM SCIENCES JI Inf. Sci. PD NOV PY 2001 VL 139 IS 1-2 BP 3 EP 17 DI 10.1016/S0020-0255(01)00155-4 PG 15 WC Computer Science, Information Systems SC Computer Science GA 500RV UT WOS:000172641300002 ER PT J AU Brown, GE Parks, GA AF Brown, GE Parks, GA TI Sorption of trace elements on mineral surfaces: Modern perspectives from spectroscopic studies, and comments on sorption in the marine environment SO INTERNATIONAL GEOLOGY REVIEW LA English DT Review ID X-RAY-ABSORPTION; OXIDE-WATER INTERFACE; GOETHITE ALPHA-FEOOH; HYDROUS FERRIC-OXIDE; AMORPHOUS IRON OXYHYDROXIDE; ELECTRICAL DOUBLE-LAYER; HYDROLYZABLE METAL-IONS; NATURAL ORGANIC-MATTER; HYDROTALCITE-LIKE COMPOUNDS; BOND-VALENCE DETERMINATION AB The partitioning (or sorption) of trace elements from aqueous solutions onto mineral surfaces and natural organic matter (NOM) has played a major role in determining the trace element content of natural waters. This review examines sorption processes on mineral surfaces for nine trace elements (Cr, Co, Ni, Cu, Zn, Sr, Cd, Hg, Pb), focusing on the results of modern x-ray spectroscopic studies. Such studies provide unique information on the structure and composition of sorption products, including their mode of attachment to mineral surfaces or functional groups in NOM under in situ conditions (i.e., with aqueous solution present at 25degreesC). The types of chemical reactions (acid-base, ligand exchange, redox, dissolution/reprecipitation) that can occur at mineral-aqueous solution interfaces are also reviewed, and some of the factors that affect the reactivity of mineral surfaces are discussed, including changes in the geometric and electronic structures of mineral surfaces when they first react with aqueous solutions and constraints on the bonding of adions to surface functional groups imposed by Pauling bond valence sums. A summary of electrical double layer (EDL) theory is presented, including the results of several recent x-ray spectroscopic and parameter regression studies of the EDL for metal-(oxyhydr)oxide-aqueous solution interfaces. The effects of common inorganic and organic complexants on the sorption of trace metal cations at mineral-solution interfaces are considered, in the context of spectroscopic studies where possible. The results of sorption studies of trace metal cations on NOM, common bacteria, and marine biomass are reviewed, and the effects of coatings of NOM and microbial biofilms on cation uptake on mineral surfaces are discussed, based on macroscopic and spectroscopic data. The objective here is to assess the relative importance of inorganic versus organic sorption processes in aquatic systems. The paper concludes with a discussion of the effects of water composition on trace element removal mechanisms, with the aim of providing an understanding of the effects of the high salinity of seawater on trace element sorption processes. The information presented in this review indicates that sorption processes on mineral, NOM, and microbial and algal surfaces, including true adsorption and precipitation, are highly effective at removing trace elements from natural waters and generally supports Krauskopf's (1956) conclusion that such processes are likely responsible for the present trace element concentrations in seawater. C1 Stanford Univ, Dept Geol & Environm Sci, Surface & Aqueous Geochem Grp, Stanford, CA 94305 USA. Stanford Synchrotron Radiat Lab, SLAC, Menlo Pk, CA 94025 USA. RP Brown, GE (reprint author), Stanford Univ, Dept Geol & Environm Sci, Surface & Aqueous Geochem Grp, Stanford, CA 94305 USA. NR 788 TC 125 Z9 127 U1 3 U2 71 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 0020-6814 EI 1938-2839 J9 INT GEOL REV JI Int. Geol. Rev. PD NOV PY 2001 VL 43 IS 11 BP 963 EP 1073 PG 111 WC Geology SC Geology GA 537UK UT WOS:000174777800001 ER PT J AU Miller, JA Klippenstein, SJ AF Miller, JA Klippenstein, SJ TI The reaction between ethyl and molecular oxygen II: Further analysis SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID C2H5+O-2 REACTION; PRESSURE-DEPENDENCE; UNIMOLECULAR REACTIONS; CHEMICAL ACTIVATION; RATE COEFFICIENTS; REACTION-KINETICS; MASTER EQUATION; C2H4 YIELD; MECHANISM; COMBUSTION AB The present investigation is a rather substantial extension and elaboration of our previous work on the same reaction, In this article we accomplish four primary objectives: 1. We show quantitatively how sensitive the high-temperature rate coefficient k(T) is to E-02, the threshold energy of the transition state for direct molecular elimination of HO2 from ethylperoxy radical (C2H5O2), thus deducing a value of E-02 = -3.0 kcal/mol (measured from reactants), 2. We derive the result that k(0)(T) approximate to k ' (infinity)(T) in the high-temperature regime, where k(0)(T) is the zero-pressure rate coefficient, and k ' (infinity)(T) is the infinite-pressure rate coefficient for the bimolecular channel. 3. Most importantly. we discuss the three different regimes of the reaction (low-temperature, transition, and high-temperature) in terms of the eigenvectors and eigenvalues of G, the transition matrix of the master equation, The transition regime is shown to be a region of avoided crossing between the two chemically significant eigenvalue curves in which the thermal rate coefficient kj,p) jumps from one eigenvalue to the other. This jump is accompanied by a "mixing" of the corresponding eigenvectors, through which both eigenvectors deplete the reactant. The onset of the high-temperature regime is triggered by reaching the "stabilization limit" of the ethylperoxy adduct, a limit that is induced by a shift in equilibrium of the stabilization reaction, our identification of the prompt and secondary HO2 formed by the reaction with these eigenvalue/eigenvector pairs leads to good agreement between theory and the experiments of Clifford et al. (J Phys Chem A 2000, 104, 11549-11560). 4. Lastly, we describe the master equation results in terms of a set of elementary reactions and phenomenological rate coefficients. (C) 2001 John Wiley & Sons, Inc. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Miller, JA (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. OI Klippenstein, Stephen/0000-0001-6297-9187 NR 38 TC 83 Z9 83 U1 5 U2 27 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD NOV PY 2001 VL 33 IS 11 BP 654 EP 668 DI 10.1002/kin.1063 PG 15 WC Chemistry, Physical SC Chemistry GA 480VJ UT WOS:000171483200004 ER PT J AU Sutherland, JW Su, MC Michael, JV AF Sutherland, JW Su, MC Michael, JV TI Rate constants for H+CH4, CH3+H-2, and CH4 dissociation at high temperature SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID TRANSITION-STATE THEORY; THERMAL RATE CONSTANTS; AB-INITIO DYNAMICS; HYDROGEN ABSTRACTION REACTIONS; POTENTIAL-ENERGY SURFACES; DENSITY-FUNCTIONAL THEORY; COLLISION RATE CONSTANTS; REFLECTED SHOCK-WAVES; H-2 REVERSIBLE CH4+H; FALL-OFF RANGE AB The Laser Photolysis-Shock Tube technique coupled with H-atom atomic resonance absorption spectrometry has been used to study the reaction, H + CH4 CH3 + H-2, over the temperature range, 928-1697 K. Shock-tube studies on the reverse of this reaction, CH3 + H-2 --> H + CH4, using CH(3)l dissociation in the presence of H2 yielded H-atom formation rates and rate constants for the reverse process over the temperature range, 1269-1806 K. These results were transformed (using well-established equilibrium constants) to the forward direction, The combined results for H + CH4 can be represented by an experimental three parameter expression, k = 6.78 x 10(-21) T (3.156) exp(-4406 K/T) cm(3) molecule(-1) s(-1) (348-1950 K) that was evaluated from the present work and seven previous studies Using this evaluation, disagreements between previously reported values for the dissociation Of CH4 could be reconciled The thermal decomposition of CH4 was then studied in Kr bath gas. The dissociation results agreed with the earlier studies and were theoretically modeled with the Troe formalism. The energy transfer parameter necessary to explain both the present results and those of Kiefer and Kumaran (J Phys Chem 1993, 97,414) is, -< Delta E > (all)/cm(-1) = 0.3323 T-0.7. The low temperature data on the reverse reaction, H + CH3 (in He) from Brouard et al. (I Phys Chem 1989, 93, 4047) were also modeled with the Troe formalism. Lastly, the rate constant for H + CH4 was theoretically calculated using conventional transition state theory with Eckart tunneling corrections, The potential energy surface used was from Kraka et al. (J Chem Phys 1993, 99, 5306) and the derived T-dependence with this method agreed almost perfectly with the experimental evaluation. (C) 2001 John Wiley & Sons, Inc. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Butler Univ, Dept Chem, Indianapolis, IN 46208 USA. RP Michael, JV (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Michael, Joe/E-3907-2010 NR 94 TC 101 Z9 101 U1 6 U2 28 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD NOV PY 2001 VL 33 IS 11 BP 669 EP 684 DI 10.1002/kin.1064 PG 16 WC Chemistry, Physical SC Chemistry GA 480VJ UT WOS:000171483200005 ER PT J AU Shepard, CL Cannon, BD Khaleel, MA AF Shepard, CL Cannon, BD Khaleel, MA TI Determination of temperature in glass with a fluorescence method SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article ID NA2O-CAO-MGO-SIO2 GLASSES; INTENSITY RATIO; SILICA FIBER; ABSORPTION; SPECTRA; WATER; IRON AB We have developed a method for measurement of temperature in glass products with the following features: (1) noncontacting, (2) real time, and (3) through-thickness. The method is based on fluorescence emission. Many glass products include Fe2O3 as an additive in various amounts. Ferric (Fe3+) and ferrous (Fe2+) ions absorb light in the ultraviolet and infrared parts of the spectrum. Absorption of light by iron ions in glass results in a predictable fluorescence emission. The emission in turn depends on the glass temperature, and this dependence is the basis for our method of measuring temperature. We have measured the fluorescence emission lifetimes in several commercial automotive glass samples over a temperature range from 25 degreesC to 550 degreesC (about 300-825 K). Imaging the fluorescence emission from glass samples onto a segmented photomultiplier tube provided spatially resolved measurements. A simple model that relates the temperature to the fluorescence lifetime has been developed. Published by Elsevier Science Ltd. C1 Pacific NW Natl Lab, Engn Mech Grp, Richland, WA 99352 USA. RP Khaleel, MA (reprint author), Pacific NW Natl Lab, Engn Mech Grp, POB 999,K2-18, Richland, WA 99352 USA. OI khaleel, mohammad/0000-0001-7048-0749 NR 11 TC 3 Z9 3 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0017-9310 J9 INT J HEAT MASS TRAN JI Int. J. Heat Mass Transf. PD NOV PY 2001 VL 44 IS 21 BP 4027 EP 4034 DI 10.1016/S0017-9310(01)00046-1 PG 8 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA 469JE UT WOS:000170810100004 ER PT J AU Warren, TL Poormon, KL AF Warren, TL Poormon, KL TI Penetration of 6061-T6511 aluminum targets by ogive-nosed VAR 4340 steel projectiles at oblique angles: experiments and simulations SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article ID ELASTIC-PLASTIC TARGET; STRIKING VELOCITIES; RIGID PROJECTILE; 3.0 KM/S; RODS AB In this paper we present the results from a combined experimental. analytical., and computational penetration program. First, we conducted a series of depth-of-penetration experiments using 0.021 kg, 7.11 mm diameter, 71.12 mm long, vacuum-arc-remelted 4340 ogive-nose steel projectiles. These projectiles were launched with striking velocities between 0.5 and 1.3 km/s using a 20 mm powder gun into 254 mm diameter, 6061-T6511 aluminum targets with angles of obliquity of 15 degrees, 30 degrees, and 45 degrees. Next, we employed the initial conditions obtained from the experiments with a new technique that we have developed to calculate permanent projectile deformation without erosion. With this technique we use an explicit. transient dynamic., finite element code to model the projectile and an analytical forcing function derived from the dynamic expansion of a spherical cavity (which accounts for compressibility, strain hardening, strain-rate sensitivity, and a finite boundary) to represent the target. Results from the simulations show the final projectile positions are in good agreement with the positions obtained from post-test radiographs. Published by Elsevier Science Ltd. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. RP Warren, TL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 30 TC 25 Z9 40 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD NOV PY 2001 VL 25 IS 10 BP 993 EP 1022 DI 10.1016/S0734-743X(01)00024-0 PG 30 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 473ZB UT WOS:000171078700005 ER PT J AU Harrison, WTA Phillips, MLF Nenoff, TM AF Harrison, WTA Phillips, MLF Nenoff, TM TI (CN4H7)(2)center dot Zn-3(HPO3)(4), a three-dimensional framework zincophosphite: an example of template-template co-operation? SO INTERNATIONAL JOURNAL OF INORGANIC MATERIALS LA English DT Article DE zinc properties; templated solids; crystal structures AB The hydrothermal synthesis and single crystal structure of (CN4H7)(2). Zn-3(HPO3)(4) are reported. This phase is built up from a network of vertex-linked ZnO4 and HPO3 building units encapsulating the extra-framework animoguanidinium cations. A new type of three-dimensional network for the inorganic component of the structure arises, which contains polyhedral 4-, 6-, 8-, 12- and 16-fings. There are close (similar to3.6 Angstrom), side-on, template-template contacts similar to those seen between pairs of guanidinium cations in molecular compounds. Crystal data: (CN4H7)(2). Zn-3(HPO3)(4), M-r = 666.30, monoclinic, space group P2(1)/n (No. 14), a = 10.2589 (4) Angstrom, b = 29.5851 (12) Angstrom, c = 13.7578 (5) Angstrom, beta = 103.303 (1)degrees, V = 4063.6 (5) Angstrom (3), Z = 8, T = 298 (2) K, R(F) = 0.0399, wR(F-2) = 0.0792. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Aberdeen, Dept Chem, Aberdeen AB24 3UE, Scotland. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Harrison, WTA (reprint author), Univ Aberdeen, Dept Chem, Meston Walk, Aberdeen AB24 3UE, Scotland. NR 16 TC 48 Z9 48 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1466-6049 J9 INT J INORG MATER JI Int. J. Inorg. Mater. PD NOV PY 2001 VL 3 IS 7 BP 1033 EP 1038 DI 10.1016/S1466-6049(01)00076-9 PG 6 WC Chemistry, Inorganic & Nuclear; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 503XQ UT WOS:000172827300063 ER PT J AU George, DL Shollenberger, KA Torczynski, JR O'Hern, TJ Ceccio, SL AF George, DL Shollenberger, KA Torczynski, JR O'Hern, TJ Ceccio, SL TI Three-phase material distribution measurements in a vertical flow using gamma-densitometry tomography and electrical-impedance tomography SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Article DE gamma-densitometry tomography; electrical-impedance tomography; bubble column; gas volume fraction; multiphase flow ID BUBBLE-COLUMNS; 2-PHASE; SYSTEMS AB Experiments are presented in which electrical-impedance tomography (EIT) and gamma-densitometry tomography (GDT) measurements are combined to simultaneously measure the solid, liquid, and gas radial distributions in a vertical three-phase flow. The experimental testbed is a 19.05-cm diameter bubble column in which gas is injected at the bottom and exits out the top while the liquid and solid phases recirculate. The gas phase is air and the liquid phase is deionized water with added electrolytes. For the solid phase four different particle classes are investigated: 40-100 mum and 120-200 mum glass particles (2.41 g/cm(3)), and 170-260 mum and 200-700 mum polystyrene particles (1.04 g/cm(3)). Superficial gas velocities of 3-30 cm/s and solid volume fractions up to 0.30 are examined. For all experimental conditions investigated, the gas distribution shows only a weak dependence on both particle size and density. The average gas volume fraction as a function of superficial gas velocity can be described to within +/-0.04 by a single curve. For most cases, the solid particles appear to be uniformly dispersed in the liquid. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Engn Sci Ctr, Albuquerque, NM 87185 USA. Univ Michigan, Dept Mech Engn & Appl Mech, Ann Arbor, MI 48109 USA. RP Shollenberger, KA (reprint author), Sandia Natl Labs, Engn Sci Ctr, POB 5800, Albuquerque, NM 87185 USA. NR 29 TC 24 Z9 24 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD NOV PY 2001 VL 27 IS 11 BP 1903 EP 1930 DI 10.1016/S0301-9322(01)00042-8 PG 28 WC Mechanics SC Mechanics GA 484JR UT WOS:000171686900003 ER PT J AU Sepulveda-Torres, LD Zhou, JZ Guasp, C Lalucat, J Knaebel, D Plank, JL Criddle, CS AF Sepulveda-Torres, LD Zhou, JZ Guasp, C Lalucat, J Knaebel, D Plank, JL Criddle, CS TI Pseudomonas sp strain KC represents a new genomovar within Pseudomonas stutzeri SO INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY LA English DT Article DE Pseudomonas strain KC; phylogeny and taxonomy; genomovar; carbon tetrachloride biodegradation; pyridine-2,6-bis(thiocarboxylate) ID CARBON-TETRACHLORIDE DEHALOGENATION; SEQUENCE-ANALYSIS; SP-NOV; IDENTIFICATION; BACTERIA; PCR; DENITRIFICATION; TRANSFORMATION; DEFINITION AB Pseudomonas sp. strain KC (= ATCC 55595 = DSM 7136) is a denitrifying aquifer isolate that produces and secretes pyridine-2,6-bis(thiocarboxylate) (PDTC), a chelating agent that fortuitously transforms carbon tetrachloride without producing chloroform. Although KC has been used successfully for full-scale bioremediation of carbon tetrachloride, its taxonomy has proven difficult to resolve, as it retains properties of both Pseudomonas stutzeri and Pseudomonas putida. In the present work, a polyphasic approach was used to conclude that strain KC represents a new genomovar (genomovar 9) within the species P. stutzeri. C1 Michigan State Univ, Dept Microbiol, E Lansing, MI 48823 USA. Michigan State Univ, Natl Sci Fdn, Ctr Microbial Ecol, E Lansing, MI 48823 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Illes Balears, Microbiol Dept Biol, Palma de Mallorca, Spain. Inst Mediterrani Estudis Avancats, Palma de Mallorca, Spain. Clarkson Univ 5805, Dept Biol, Potsdam, NY 13699 USA. Stanford Univ, Dept Civil & Environm Engn, Stanford, CA 94305 USA. RP Sepulveda-Torres, LD (reprint author), Univ Metropolitana, Dept Sci & Technol, POB 21150, San Juan, PR 00928 USA. RI Lalucat, Jorge/K-1127-2014 OI Lalucat, Jorge/0000-0002-8350-6087 FU NIEHS NIH HHS [ES04911] NR 44 TC 15 Z9 15 U1 0 U2 4 PU SOC GENERAL MICROBIOLOGY PI READING PA MARLBOROUGH HOUSE, BASINGSTOKE RD, SPENCERS WOODS, READING RG7 1AE, BERKS, ENGLAND SN 1466-5026 J9 INT J SYST EVOL MICR JI Int. J. Syst. Evol. Microbiol. PD NOV PY 2001 VL 51 BP 2013 EP 2019 PN 6 PG 7 WC Microbiology SC Microbiology GA 496BG UT WOS:000172374400010 PM 11760942 ER PT J AU Lookman, T Williams, TO Saxena, A AF Lookman, T Williams, TO Saxena, A TI Effect of solid-solid phase transformations on elastic constitutive relations SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 5th European Symposium on Martensitic Transformations (ESOMAT2000) CY SEP 04-08, 2000 CL COMO, ITALY SP Univ Studi Milano, Univ Studi Milano Bicocca, Inst TemPE Consiglio Nazl Ric, INFM, Soc Pirelli, Amministrazione Provinciale Como, Soc Optigen, Soc LT Calcoli AB A two-dimensional (2D) Ginzburg-Landau (GL) theory for temperature induced phase transformations in single crystals is extended to incorporate the effects of mechanical and thermal (expansion or dilatational) strain effects. This extension of the GL theory allows the single crystal GL model to be implemented into polycrystalline homogenization schemes. The proposed model is capable of examining the interactions of applied mechanical loading states and phase transformation processes within single crystals. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Lookman, T (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 5 TC 1 Z9 1 U1 1 U2 1 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD NOV PY 2001 VL 11 IS PR8 BP 11 EP 15 DI 10.1051/jp4:2001802 PG 5 WC Physics, Multidisciplinary SC Physics GA 511FK UT WOS:000173253800003 ER PT J AU Kadau, K Entel, P Germann, TC Lomdahl, PS Holian, BL AF Kadau, K Entel, P Germann, TC Lomdahl, PS Holian, BL TI Large-scale molecular-dynamics study of the nucleation process of martensite in Fe-Ni alloys SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 5th European Symposium on Martensitic Transformations (ESOMAT2000) CY SEP 04-08, 2000 CL COMO, ITALY SP Univ Studi Milano, Univ Studi Milano Bicocca, Inst TemPE Consiglio Nazl Ric, INFM, Soc Pirelli, Amministrazione Provinciale Como, Soc Optigen, Soc LT Calcoli ID SIMULATIONS; TRANSFORMATIONS; TRANSITION; METALS AB High-performance large-scale molecular-dynamics (MD) simulations provide an atomistic insight of the nucleation process in Fe80Ni20. With the MD code SPaSM (Scalable Parallel Short-range Molecular Dynamics [1]) it is possible to follow the nucleation and further growth of the martensite structure (bee) for more than one million atoms. The simulations show that the nucleation process is heterogeneous, at pre-existing defects. Further growth of the martensite structure into the austenite matrix (fee) forms a typical twin structure on the nanoscale. Analysis of energy barriers between the martensite and the austenite can be used to interpret the nucleation process. C1 Gerhard Mercator Univ Duisburg, D-47048 Duisburg, Germany. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Kadau, K (reprint author), Gerhard Mercator Univ Duisburg, Lotharstr 1, D-47048 Duisburg, Germany. NR 15 TC 12 Z9 12 U1 0 U2 6 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD NOV PY 2001 VL 11 IS PR8 BP 17 EP 22 DI 10.1051/jp4:2001803 PG 6 WC Physics, Multidisciplinary SC Physics GA 511FK UT WOS:000173253800004 ER PT J AU Jovanovic, I Comaskey, BJ Pennington, DM AF Jovanovic, I Comaskey, BJ Pennington, DM TI Angular effects and beam quality in optical parametric amplification SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GENERATION; LASER AB Advances in optical parametric devices, in particular those requiring high conversion efficiency, rely on pump laser and gain medium properties. We describe and theoretically model the source of dephasing due to angular deviation from ideal phase matching in optical parametric amplification. Real laser beams have angular content, which is described by their spatial frequency spectrum. Such beams cannot be treated as single plane waves in nonlinear interactions. Our mathematical model is based on a plane wave decomposition of Gaussian and top-hat beams into their components in spatial frequencies. Several popular nonlinear materials (beta-barium borate, lithium borate, and potassium dihydrogen phosphate) are examined for phase matching angles and dephasing is rigorously calculated. The impact of the beam angular content on small signal gain and on conversion efficiency in the strongly depleted regime is evaluated numerically. In addition, a criterion is formulated for beam quality tolerance in optical parametric amplifiers, for critical and noncritical phase matching. The impact of initial conditions in optical parametric amplification is considered. Our calculations are intended primarily for devices pumped with long (nanosecond) pulses. (C) 2001 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Jovanovic, I (reprint author), Lawrence Livermore Natl Lab, Mail Code L-399,7000 East Ave, Livermore, CA 94550 USA. NR 17 TC 25 Z9 26 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 2001 VL 90 IS 9 BP 4328 EP 4337 DI 10.1063/1.1407312 PG 10 WC Physics, Applied SC Physics GA 482UE UT WOS:000171594800004 ER PT J AU Mahan, GD Gladden, JR Maynard, JD AF Mahan, GD Gladden, JR Maynard, JD TI Elastic oscillations of cylindrical fuses SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID IMPULSE-INDUCED FRACTURE; VARISTOR; CONSTANTS AB A fast current pulse causes a material to heat and undergo rapid expansion. We calculate the response of a cylindrically shaped material to a pulse on the microsecond time scale. The first step is to obtain the breathing modes of elastic oscillation of the cylinder. These modes are calculated using a Rayleigh-Ritz variational method introduced by Demarest for cubes. The boundary conditions are derived, which give the amplitude of each elastic mode in response to the sudden heating. The results are illustrated by calculations on a station arrester made of a ZnO ceramic. (C) 2001 American Institute of Physics. C1 Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Penn State Univ, Dept Phys & Astron, Davey Lab 104, University Pk, PA 16802 USA. RP Mahan, GD (reprint author), Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. NR 15 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 2001 VL 90 IS 9 BP 4415 EP 4422 DI 10.1063/1.1402148 PG 8 WC Physics, Applied SC Physics GA 482UE UT WOS:000171594800016 ER PT J AU Voyles, PM Zotov, N Nakhmanson, SM Drabold, DA Gibson, JM Treacy, MMJ Keblinski, P AF Voyles, PM Zotov, N Nakhmanson, SM Drabold, DA Gibson, JM Treacy, MMJ Keblinski, P TI Structure and physical properties of paracrystalline atomistic models of amorphous silicon SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MEDIUM-RANGE ORDER; TIGHT-BINDING MODEL; X-RAY-DIFFRACTION; DISORDERED MATERIALS; MOLECULAR-DYNAMICS; VIBRATIONAL PROPERTIES; COMPUTER-SIMULATION; A-SI; FLUCTUATION MICROSCOPY; OPTICAL-PROPERTIES AB We have examined the structure and physical properties of paracrystalline molecular dynamics models of amorphous silicon. Simulations from these models show qualitative agreement with the results of recent mesoscale fluctuation electron microscopy experiments on amorphous silicon and germanium. Such agreement is not found in simulations from continuous random network models. The paracrystalline models consist of topologically crystalline grains which are strongly strained and a disordered matrix between them. We present extensive structural and topological characterization of the medium range order present in the paracrystalline models and examine their physical properties, such as the vibrational density of states, Raman spectra, and electron density of states. We show by direct simulation that the ratio of the transverse acoustic mode to transverse optical mode intensities I(TA)/I(TO) in the vibrational density of states and the Raman spectrum can provide a measure of medium range order. In general, we conclude that the current paracrystalline models are a good qualitative representation of the paracrystalline structures observed in the experiment and thus provide guidelines toward understanding structure and properties of medium-range-ordered structures of amorphous semiconductors as well as other amorphous materials. (C) 2001 American Institute of Physics. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. NEC Res Inst, Princeton, NJ 08540 USA. Univ Bayreuth, Bayer Geoinst, D-95440 Bayreuth, Germany. Ohio Univ, Dept Phys & Astron, Condensed Matter & Surface Sci Program, Athens, OH 45701 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Rensselaer Polytech Inst, Dept Mat Sci & Engn, Troy, NY 12180 USA. RP Voyles, PM (reprint author), Bell Labs, 700 Mt Ave, Murray Hill, NJ 07079 USA. EM pvoyles@bell-labs.com RI Gibson, Murray/E-5855-2013; Nakhmanson, Serge/A-6329-2014; OI Gibson, Murray/0000-0002-0807-6224; Voyles, Paul/0000-0001-9438-4284; Drabold, David/0000-0001-5344-5837 NR 60 TC 67 Z9 67 U1 2 U2 26 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 2001 VL 90 IS 9 BP 4437 EP 4451 DI 10.1063/1.1407319 PG 15 WC Physics, Applied SC Physics GA 482UE UT WOS:000171594800020 ER PT J AU Sepliarsky, M Phillpot, SR Wolf, D Stachiotti, MG Migoni, RL AF Sepliarsky, M Phillpot, SR Wolf, D Stachiotti, MG Migoni, RL TI Ferroelectric properties of KNbO3/KTaO3 superlattices by atomic-level simulation SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID LATTICE-DYNAMICS; FIRST-PRINCIPLES; SOLID-SOLUTIONS; BATIO3; PBTIO3; PBZRO3; PHASE AB We use atomic-level simulation methods to determine the zero-temperature structure and properties of coherent KNbO3/KTaO3 superlattices. We find that the in-plane behavior is essentially bulk-like with an abrupt jump in the polarization at the interfaces. By contrast, the polarization in the modulation direction is continuous through the interfaces with the interior of the KTaO3 layers remaining polarized for modulation lengths of up to 160 unit cells. The zero-frequency dielectric constant in the modulation direction has a similar magnitude to that of KNbO3. An investigation of the switching behavior shows that for modulation lengths greater than 24 unit cells, each KNbO3 layer behaves essentially independently. For modulation lengths of less than 12 unit cells, the KNbO3 layers interact so strongly with each other that the superlattice essentially behaves as a single artificial structure. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. UNR, CONICET, Inst Fis Rosario, Rosario, Santa Fe, Argentina. RP Phillpot, SR (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Phillpot, Simon/J-9117-2012; OI Phillpot, Simon/0000-0002-7774-6535 NR 23 TC 45 Z9 45 U1 2 U2 12 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 2001 VL 90 IS 9 BP 4509 EP 4519 DI 10.1063/1.1410329 PG 11 WC Physics, Applied SC Physics GA 482UE UT WOS:000171594800030 ER PT J AU Pecharsky, VK Gschneidner, KA AF Pecharsky, VK Gschneidner, KA TI Some common misconceptions concerning magnetic refrigerant materials SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TEMPERATURE SPECIFIC-HEAT; MAGNETOCALORIC PROPERTIES; ENTROPY CHANGE; PHASE-TRANSITIONS; ROOM-TEMPERATURE; MANGANESE OXIDES; PEROVSKITES; CAPACITY; NA AB The relationships between both extensive and intensive properties quantifying the magnetocaloric effect, i.e., between the isothermal entropy change and the adiabatic temperature change, respectively, have been analyzed. An extensive measure of the magnetocaloric effect alone, without considering another important and also extensive thermodynamic property, i.e., the heat capacity, may lead to biased conclusions about the size of the magnetocaloric effect and, consequently, about the applicability of a magnetic material as a magnetic refrigerant. The near room temperature magnetocaloric properties of the colossal magnetoresistive manganites [(R1-xMx)MnO3, where R=lanthanide metal and M is alkaline earth metal] and the recently discovered Fe-based intermetallic material (LaFe11.47Co0.23Al1.3) have been reaccessed and correctly compared with those of the metallic Gd prototype. Our analysis has shown that these 3d materials are inferior to Gd by a factor of 2 or more because of the high values of the heat capacity per unit mass. Also a comparison of the volumetric isothermal entropy change, which is a critical parameter for the operation of a refrigeration unit, indicates that Gd is superior to these 3d materials for practical applications. (C) 2001 American Institute of Physics. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Pecharsky, VK (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 42 TC 173 Z9 178 U1 2 U2 43 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 2001 VL 90 IS 9 BP 4614 EP 4622 DI 10.1063/1.1405836 PG 9 WC Physics, Applied SC Physics GA 482UE UT WOS:000171594800044 ER PT J AU Zhang, YT Floyd, M Drucker, J Kellogg, GL AF Zhang, YT Floyd, M Drucker, J Kellogg, GL TI Spontaneously forming nanostructures: Quantum dot molecules and rings SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GE ISLANDS; MICROSTRUCTURAL EVOLUTION; GE/SI(100) ISLANDS; COHERENT ISLANDS; SHAPE TRANSITION; SI(001); SI(100) AB Annealing molecular beam epitaxy grown Ge/Si(100) islands spontaneously forms quantum dot molecules and rings. Quantum dot molecules (QDM) are close-packed arrays of several SiGe alloy hut clusters arranged with rectangular or circular symmetry. Rings are 3D structures with a depressed center. Both of these structures are related to island ensemble coarsening. Si interdiffusion into the perimeter of nominally pure Ge dome clusters forms a Si-rich annulus surrounding a Ge rich core. This lower melting point core diffuses away during coarsening of the island ensemble leaving behind the QDM. Large ring structures are formed by rapid coarsening of large, dislocated clusters during high temperature anneals. (C) 2001 American Institute of Physics. C1 Arizona State Univ, Ctr Solid State Sci, Dept Phys & Astron, Tempe, AZ 85287 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Zhang, YT (reprint author), Arizona State Univ, Ctr Solid State Sci, Dept Phys & Astron, Tempe, AZ 85287 USA. NR 25 TC 16 Z9 16 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 2001 VL 90 IS 9 BP 4748 EP 4754 DI 10.1063/1.1407311 PG 7 WC Physics, Applied SC Physics GA 482UE UT WOS:000171594800062 ER PT J AU Epstein, RI Brown, JJ Edwards, BC Gibbs, A AF Epstein, RI Brown, JJ Edwards, BC Gibbs, A TI Measurements of optical refrigeration in ytterbium-doped crystals SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID YB3+-DOPED GLASSES; ROOM-TEMPERATURE; LASER AB We measured anti-Stokes fluorescence cooling (optical refrigeration) in ytterbium-doped yttrium aluminum garnet (YAG). Pumping the 2.3% Yb3+:YAG crystal with 1.8 W of 1030 nm laser light produced a temperature drop of 8.9 degreesC from room temperature. The high thermal conductivity and ruggedness of this crystal make it an attractive material for use in optical refrigerators. Our spectral studies show that pure crystals of this material could be efficient for optical refrigeration at temperatures above similar to 100 K. Photothermal deflection measurements show that our current crystals can cool at similar to 250 K. Additionally, we measured optical refrigeration in a 5% Yb3+:Y2SiO5 crystal when pumped at 1050 nm. (C) 2001 American Institute of Physics. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Epstein, RI (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Brown, Joseph/H-4957-2014 OI Brown, Joseph/0000-0002-9838-7201 NR 13 TC 70 Z9 75 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD NOV 1 PY 2001 VL 90 IS 9 BP 4815 EP 4819 DI 10.1063/1.1406544 PG 5 WC Physics, Applied SC Physics GA 482UE UT WOS:000171594800074 ER PT J AU Dai, HJ Simonson, JM Cochran, HD AF Dai, HJ Simonson, JM Cochran, HD TI Density measurements of styrene solutions in supercritical CO2 SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID CARBON-DIOXIDE STYRENE AB Densities of styrene solutions of a wide concentration range from (0.65 to 29.9) mol % in supercritical CO2 have been measured isothermally at (40, 50, 60, and 70) degreesC at pressures to 34.47 MPa by a vibrating-tube densitometer. These results should aid in using supercritical CO2 for separation or synthesis with styrene and improving the broad database supporting supercritical fluid technologies in general. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Cochran, HD (reprint author), Oak Ridge Natl Lab, Div Chem Technol, POB 2008, Oak Ridge, TN 37831 USA. NR 12 TC 5 Z9 6 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD NOV-DEC PY 2001 VL 46 IS 6 BP 1571 EP 1573 DI 10.1021/je010116q PG 3 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 493VJ UT WOS:000172243900043 ER PT J AU Gakh, AA Burnett, MN AF Gakh, AA Burnett, MN TI Modular Chemical Descriptor Language (MCDL): Composition, connectivity, and supplementary modules SO JOURNAL OF CHEMICAL INFORMATION AND COMPUTER SCIENCES LA English DT Article ID LINE NOTATION; REPRESENTATION; ASSIGNMENT; ALGORITHM; SYMMETRY; SYSTEM; SMILES; ATOMS AB The Modular Chemical Descriptor Language (MCDL) was developed to address the need for linear representation of structural and other chemical information for chemical databases, E-journals, and the Internet. The current paper describes in detail two major modules of the language: the composition and connectivity modules. which provide a representation of chemical structure. These modules are created using simple hierarchical principles based on ASCII codes and are unique except for stereoisomers and a few special cases (e.g., valence isomers, knot-type compounds). The MCDL also provides for additional information (such as atom coordinates, bond orders, spectra, and physical-chemical characteristics) to be included as a set of supplementary modules. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Gakh, AA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 22 TC 7 Z9 7 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0095-2338 J9 J CHEM INF COMP SCI JI J. Chem. Inf. Comput. Sci. PD NOV-DEC PY 2001 VL 41 IS 6 BP 1494 EP 1499 DI 10.1021/ci000108y PG 6 WC Chemistry, Multidisciplinary; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications SC Chemistry; Computer Science GA 497MM UT WOS:000172459600009 PM 11749574 ER PT J AU Nestorov, VK Hinchliffe, RD Uberna, R Cline, JI Lorenz, KT Chandler, DW AF Nestorov, VK Hinchliffe, RD Uberna, R Cline, JI Lorenz, KT Chandler, DW TI Measurement of bipolar moments for photofragment angular correlations in ion imaging experiments SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID VECTOR CORRELATIONS; MULTIPHOTON IONIZATION; PHOTODISSOCIATION; SPECTROSCOPY; 2-CHLORO-2-NITROSOPROPANE; POLARIZATION; ALIGNMENT; DYNAMICS; DISTRIBUTIONS; DISSOCIATION AB A general numerical method is given to extract angular correlations from photodissociation experiments with ion imaging detection. The angular correlations among the transition dipole moment of the parent molecule, mu, the photoproduct recoil velocity, v, and its angular momentum, j, are parametrized analytically using the semiclassical bipolar moment scheme due to Dixon. The method is a forward-convolution scheme which allows quantitative extraction of all measurable bipolar moments and can be applied in experiments with both linearly and circularly polarized probe light. It avoids the cylindrical symmetry limitations of the inverse Abel transform method, traditionally used for extracting photoproduct recoil anisotropy and speed distribution from imaging data. The method presented here also takes into account the possibility of multiple photodissociation channels. The features of the method are illustrated in a two-color 1+1' REMPI-ion imaging study of the NO photoproduct trajectories resulting from the 650 nm photodissociation of 2-chloro-2-nitrosopropane (CNP). A comparison between experimental and synthetic images is presented for selected experimental geometries. The experimental images for CNP and the results from their fit confirm earlier TOF studies showing that the recoil speed distribution is bimodal with the low and high speed components having average values of approximately 500 and 910 m/s. These components have been previously assigned to dissociation from the S-0 and T-1 electronic states of the parent molecule, respectively. The experimental results from the current study also confirm that for the high-speed component the product NO velocity vector, v, is preferentially perpendicular to its angular momentum, j [beta (0)(0)(22)=-0.21], and that there is no significant correlation between v and the transition dipole moment mu of the CNP molecule [beta (2)(0)(20)=-0.02]. (C) 2001 American Institute of Physics. C1 Univ Nevada, Dept Chem, Reno, NV 89557 USA. Univ Nevada, Chem Phys Program, Reno, NV 89557 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Nestorov, VK (reprint author), Univ Nevada, Dept Chem, Reno, NV 89557 USA. NR 34 TC 21 Z9 21 U1 5 U2 15 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 1 PY 2001 VL 115 IS 17 BP 7881 EP 7891 DI 10.1063/1.1408914 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 483QU UT WOS:000171647900011 ER PT J AU Gutsev, GL Jena, P Zhai, HJ Wang, LS AF Gutsev, GL Jena, P Zhai, HJ Wang, LS TI Electronic structure of chromium oxides, CrOn- and CrOn (n=1-5) from photoelectron spectroscopy and density functional theory calculations SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TRANSITION-METAL OXIDES; GAS-PHASE; INFRARED-SPECTRA; MONOXIDE ANIONS; NEGATIVE-ION; SOLID ARGON; CLUSTERS; ATOMS; EXCHANGE; 3D AB The electronic structure of CrOn- and CrOn (n=1-5) was investigated using anion photoelectron spectroscopy and density functional theory. Photoelectron spectra of CrOn- were obtained at several photon energies and yielded electron affinities, vibrational and electronic structure information about the neutral CrOn species. Density functional theory calculations were carried out for both the neutrals and anions and were used to interpret the experimental spectra. Several low-lying electronic states of CrO were observed and assigned from photodetachment of the CrO- ground state ((6)Sigma (+)) and an excited state ((4)Pi), which is only 0.1 eV higher. The main spectral features of CrO2- were interpreted based on a C-2v CrO2- (B-4(1)). A very weak Cr(O-2)(-) isomer was also observed with lower electron binding energies. Relatively simple and vibrationally resolved spectra were observed for CrO3-, which was determined to be D-3h. The CrO3 neutral was calculated to be C-3v with the Cr atom slightly out of the plane of the three O atoms. The spectrum of CrO4- revealed a very high electron binding energy. Several isomers of CrO4- were predicted and the ground state has a distorted tetrahedral structure (C-2) without any O-O bonding. Only one stable structure was predicted for CrO5- with a superoxo O-2 bonded to a C-3v CrO3. (C) 2001 American Institute of Physics. C1 Virginia Commonwealth Univ, Dept Phys, Richmond, VA 23284 USA. Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Gutsev, GL (reprint author), NASA, Ames Res Ctr, Mail Stop 230-3, Moffett Field, CA 94035 USA. NR 52 TC 85 Z9 88 U1 4 U2 20 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 1 PY 2001 VL 115 IS 17 BP 7935 EP 7944 DI 10.1063/1.1405438 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 483QU UT WOS:000171647900016 ER PT J AU Xing, JH AF Xing, JH TI Statistical thermodynamics of lattice models SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article AB This work is a generalization of the work of Widom [J. Chem. Phys. 39, 2808 (1963)] and of Henderson [Mol. Phys. 95, 187 (1998)]. Based on geometric analysis and statistical thermodynamics arguments, a set of sum rules for two-component nearest-neighbor interaction models at thermodynamic equilibrium is derived. By choosing the density of one component rho and the unlike-bond density rho (12) as two variables, it is shown that the energy is well-behaved; however, the entropy, (s) over tilde(rho,rho (12)), is independent of rho within two-phase regions, but not outside. Temperature and chemical potentials determine the equilibrium rho and rho (12). The exact entropy function for 1-D systems can be calculated, and an exact free energy density function is formulated. The result shows that s is always dependent on rho except at rho (12)=0, which excludes the possibility of phase transitions at finite temperature. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Kenneth S Pitzer Ctr Theoret Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Xing, JH (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Xing, Jianhua/A-8101-2012 OI Xing, Jianhua/0000-0002-3700-8765 NR 7 TC 1 Z9 1 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 1 PY 2001 VL 115 IS 17 BP 8038 EP 8043 DI 10.1063/1.1410115 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 483QU UT WOS:000171647900028 ER PT J AU Gray, SK Goldfield, EM AF Gray, SK Goldfield, EM TI Dispersion fitted finite difference method with applications to molecular quantum mechanics SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DISTRIBUTED APPROXIMATING FUNCTIONALS; DISCRETE VARIABLE REPRESENTATION; WAVE-PACKET PROPAGATION; SCHRODINGER-EQUATION; REACTIVE SCATTERING; DYNAMICS; ALGORITHM; FOURIER AB An approach to finite difference approximation is presented based on the idea of fitting the dispersion relation up to a limiting accuracy. The resulting approximations to the second derivative can be more accurate than the standard, Lagrangian finite difference approximations by an order of magnitude or more. The locality of the methods makes them well suited to parallel computation, in contrast with pseudospectral methods. The approach is illustrated with application to a simple bound state problem and to a more challenging three dimensional reactive scattering problem. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Wayne State Univ, Dept Chem, Detroit, MI 48202 USA. RP Gray, SK (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. EM gray@anchim.chm.anl.gov; evi@sun.science.wayne.edu NR 40 TC 37 Z9 37 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV PY 2001 VL 115 IS 18 BP 8331 EP 8344 DI 10.1063/1.1408285 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 486AT UT WOS:000171796800010 ER PT J AU Robinson, JC Sun, WZ Harris, SA Qi, F Neumark, DM AF Robinson, JC Sun, WZ Harris, SA Qi, F Neumark, DM TI Photofragment translational spectroscopy of 1,2-butadiene at 193 nm SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ADVANCED LIGHT-SOURCE; VUV HIGH-RESOLUTION; HIGH-FLUX BEAMLINE; CHEMICAL-DYNAMICS; GAS-PHASE; AB-INITIO; ISOMERS; ALLENE; PHOTODISSOCIATION; DECOMPOSITION AB Photofragment translational spectroscopy has been used to investigate the dissociation dynamics of 1,2-butadiene at 193 nm. Ionization of scattered photoproducts was accomplished using tunable VUV synchrotron radiation at the Advanced Light Source. Two product channels are observed: CH3+C3H3 and C4H5+H. The C3H3 product can be identified as the propargyl radical through measurement of its photoionization efficiency curve, whereas the C4H5 product cannot be identified definitively. The translational energy P(E-T) distributions suggest that both channels result from internal conversion to the ground electronic state followed by dissociation. The P(E-T) distribution for the C4H5 product is sharply truncated below 7 kcal/mol, indicating spontaneous decomposition of the slowest C4H5 product. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Robinson, JC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RI Neumark, Daniel/B-9551-2009; Qi, Fei/A-3722-2012 OI Neumark, Daniel/0000-0002-3762-9473; NR 28 TC 22 Z9 23 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV PY 2001 VL 115 IS 18 BP 8359 EP 8365 DI 10.1063/1.1410975 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 486AT UT WOS:000171796800013 ER PT J AU McRae, RP Schenter, GK Garrett, BC Svetlicic, Z Truhlar, DG AF McRae, RP Schenter, GK Garrett, BC Svetlicic, Z Truhlar, DG TI Variational transition state theory evaluation of the rate constant for proton transfer in a polar solvent SO JOURNAL OF CHEMICAL PHYSICS LA English DT Review ID ACTIVATED CHEMICAL-REACTIONS; CURVATURE TUNNELING APPROXIMATION; EQUILIBRIUM SOLVATION DYNAMICS; MECHANICAL RATE CONSTANTS; DENSITY-MATRIX EVOLUTION; REACTION-PATH CURVATURE; HCL ACID IONIZATION; H-BONDED COMPLEXES; MOLECULAR-DYNAMICS; NONEQUILIBRIUM SOLVATION AB Variational transition state theory (VTST) is used to calculate rate constants for a model proton transfer reaction in a polar solvent. We start from an explicit description of the reacting solute in a solvent, and we model the effects of solvation on the reaction dynamics by a generalized Langevin equation (GLE) for the solute. In this description, the effects of solvation on the reaction energetics are included in the potential of mean force, and dynamical, or nonequilibrium, solvation is included by solvent friction. The GLE solvation dynamics are approximated by a collection of harmonic oscillators that are linearly coupled to the coordinates of the reacting system. This approach is applied to a model developed by Azzouz and Borgis [J. Chem. Phys. 98, 7361 (1993)] to represent proton transfer in a phenol-amine complex in liquid methyl chloride. In particular, semiclassical VTST, including multidimensional tunneling contributions, is applied to this model with three explicit solute coordinates and a multioscillator GLE description of solvation to calculate rate constants. We compare our computed rate constants and H/D kinetic isotope effects to previous calculations using other approximate dynamical theories, including approaches based on one-dimensional models, molecular dynamics with quantum transitions, and path integrals. By examining a systematic sequence of 18 different sets of approximations, we clarify some of the factors (such as classical vibrations, harmonic approximations, quantum character of reaction-coordinate motion, and nonequilibrium solvation) that contribute to the different predictions of various approximation schemes in the literature. (C) 2001 American Institute of Physics. C1 Eastern Washington Univ, Dept Chem, Cheney, WA 99004 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA. Univ Minnesota, Inst Supercomp, Minneapolis, MN 55455 USA. RP McRae, RP (reprint author), Eastern Washington Univ, Dept Chem, Cheney, WA 99004 USA. RI Garrett, Bruce/F-8516-2011; Schenter, Gregory/I-7655-2014; Truhlar, Donald/G-7076-2015 OI Schenter, Gregory/0000-0001-5444-5484; Truhlar, Donald/0000-0002-7742-7294 NR 137 TC 47 Z9 47 U1 1 U2 12 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV PY 2001 VL 115 IS 18 BP 8460 EP 8480 DI 10.1063/1.1409953 PG 21 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 486AT UT WOS:000171796800025 ER PT J AU Clegg, SL Simonson, JM AF Clegg, SL Simonson, JM TI A BET model of the thermodynamics of aqueous multicomponent solutions at extreme concentration SO JOURNAL OF CHEMICAL THERMODYNAMICS LA English DT Article DE aqueous electrolytes; thermodynamics; activity coefficients; adsorption ID ELECTROLYTE; SYSTEMS; ADSORPTION; CHLORIDE; WATER AB The statistical mechanical basis of the use of Brunauer-Emmett-Teller isotherms to represent activities and other thermodynamic properties in extremely concentrated solutions was established by Ally and Braunstein (J. Chem. Thermodynamics 1998, 30, 49-58) for a two-salt, single-solvent, mixture. Based upon the work of these authors, we have derived equations for solute and solvent activities in liquid mixtures containing a single solvent and indefinite number of solutes. New terms have been added to the model equations to express the effects of ternary ion interactions on the salt adsorption parameters. Solution composition is defined on the basis of salts, rather than ions, as components. As examples, the model is used to represent water activities in concentrated (lithium nitrate + potassium nitrate + water) and (lithium ion + sodium ion + chloride ion + nitrate ion + water) mixtures, and salt solubilities in (calcium chloride + calcium nitrate + water) mixtures. (C) 2001 Academic Press. C1 Univ E Anglia, Sch Environm Sci, Norwich NR4 7TJ, Norfolk, England. Oak Ridge Natl Lab, Phys & Mat Chem Sect, Oak Ridge, TN 37831 USA. RP Clegg, SL (reprint author), Univ E Anglia, Sch Environm Sci, Norwich NR4 7TJ, Norfolk, England. NR 21 TC 17 Z9 17 U1 3 U2 11 PU ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0021-9614 J9 J CHEM THERMODYN JI J. Chem. Thermodyn. PD NOV PY 2001 VL 33 IS 11 BP 1457 EP 1472 DI 10.1006/jcht.2001.0869 PG 16 WC Thermodynamics; Chemistry, Physical SC Thermodynamics; Chemistry GA 532ZL UT WOS:000174504900002 ER PT J AU Le Maitre, OP Knio, OM Najm, HN Ghanem, RG AF Le Maitre, OP Knio, OM Najm, HN Ghanem, RG TI A stochastic projection method for fluid flow I. Basic formulation SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE stochastic; Navier-Stokes; polynomial chaos; uncertainty ID SEMIIMPLICIT NUMERICAL SCHEME; REACTING FLOW; MEDIA; STIFF AB We describe the construction and implementation of a stochastic Navier-Stokes solver. The solver combines a spectral stochastic uncertainty representation scheme with a finite difference projection method for flow simulation. The uncertainty quantification scheme is adapted from the spectral stochastic finite element method (SSFEM), which is based on regarding uncertainty as generating a new dimension and the solution as being dependent on this dimension. In the SSFEM formalism, the stochastic dependence is represented in terms of the polynomial chaos system, and the coefficients in the corresponding spectral representation are obtained using a Galerkin approach. It is shown that incorporation of the spectral uncertainty representation scheme into the projection method results in a coupled system of advection-diffusion equations for the various uncertainty fields, and in a decoupled system of pressure projection steps. This leads to a very efficient stochastic solver, whose advantages are illustrated using steady and transient simulations of transport and mixing in a microchannel. (C) 2001 Academic Press. C1 Johns Hopkins Univ, Dept Mech Engn, Baltimore, MD 21218 USA. Univ Evry Val dEssone, F-91020 Evry, France. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. Johns Hopkins Univ, Dept Civil Engn, Baltimore, MD 21218 USA. RP Knio, OM (reprint author), Johns Hopkins Univ, Dept Mech Engn, Baltimore, MD 21218 USA. RI Knio, Omar/A-3318-2010; Ghanem, Roger/B-8570-2008; Le Maitre, Olivier/D-8570-2011 OI Ghanem, Roger/0000-0002-1890-920X; Le Maitre, Olivier/0000-0002-3811-7787 NR 24 TC 180 Z9 180 U1 1 U2 11 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 NOV 1 PY 2001 VL 173 IS 2 BP 481 EP 511 DI 10.1006/jcph.2001.6889 PG 31 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 490YK UT WOS:000172081100004 ER PT J AU McCorquodale, P Colella, P Johansen, H AF McCorquodale, P Colella, P Johansen, H TI A cartesian grid embedded boundary method for the heat equation on irregular domains SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE 35K15 initial value problems for second-order; parabolic equations; embedded boundary; moving boundaries AB We present an algorithm for solving the heat equation on irregular time-dependent domains. lt is based on the Cartesian grid embedded boundary algorithm of Johansen and Colella (1998, J. Comput. Phys. 147, 60) for discretizing Poisson's equation, combined with a second-order accurate discretization of the time derivative. This leads to a method that is second-order accurate in space and time. For the case in which the boundary is moving, we convert the moving-boundary problem to a sequence of fixed-boundary problems, combined with an extrapolation procedure to initialize values that are uncovered as the boundary moves. We find that, in the moving boundary case, the use of Crank-Nicolson time discretization is unstable, requiring us to use the Lo-stable implicit Runge-Kutta method of Twizell, Gumel, and Arigu (1996, Adv. Comput. Math. 6,333). (C) 2001 Academic Press. C1 Lawrence Berkeley Natl Lab, Appl Numer Algorithms Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. RP McCorquodale, P (reprint author), Lawrence Berkeley Natl Lab, Appl Numer Algorithms Grp, Berkeley, CA 94720 USA. NR 10 TC 79 Z9 79 U1 1 U2 9 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 NOV 1 PY 2001 VL 173 IS 2 BP 620 EP 635 DI 10.1006/jcph.2001.6900 PG 16 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 490YK UT WOS:000172081100010 ER PT J AU Paduano, L Annunziata, O Pearlstein, AJ Miller, DG Albright, JG AF Paduano, L Annunziata, O Pearlstein, AJ Miller, DG Albright, JG TI Precision measurement of ternary diffusion coefficients and implications for protein crystal growth: lysozyme chloride in aqueous ammonium chloride at 25 degrees C SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 8th International Conference on Crystallization of Biological Macromolecules CY MAY 14-19, 2000 CL SANDESTIN, FLORIDA DE diffusion; mass transfer; multicomponent diffusion; supersaturated solutions; biological macro molecules; lysozyme; salts ID MULTICOMPONENT DIFFUSION; NACL; TRANSPORT; BINARY; SALTS AB Isothermal ternary diffusion coefficients for the system lysozyme chloride (1) + NH4Cl (2) + H2O at 25 degreesC and pH 4.5 have been measured interferometrically for five mean NH4Cl concentrations, C-2 = 0.25, 0.5, 0.9, 1.2 and 1.5 M, with C-1 = 0.6 mM. The main-term diffusion coefficient (D-11)(v) varies slowly with C-2. The main-term (D-22)(v) increases with increasing NH4Cl concentration, as does the binary D-v in aqueous NH4Cl, but the (D-22)(v) values are lower in the ternary system. The cross-term (D21)v, which relates the coupled flow of NH4Cl to the protein concentration gradient, increases sharply with increasing salt concentration, and is 19 times larger than (D-22)(v) at the highest concentration. The values of (D-12)(v) are smaller than the corresponding values previously obtained for the lysozyme chloride + NaCl + H2O system over the whole range of salt concentration studied. Using equations based on the Onsager Reciprocal Relations, we have calculated the derivative of the chemical potential of lysozyme chloride with respect to the NH4Cl concentration, and have estimated the protein cation charge. Integration with respect to the NH4Cl concentration gives the dependence of the chemical potential of lysozyme chloride on NH4Cl concentration, providing information about the driving force for nucleation and crystal growth of lysozyme chloride. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Texas Christian Univ, Dept Chem, Ft Worth, TX 76129 USA. Univ Naples, Dipartimento Chim, Complesso Univ Monte S Angelo, I-80126 Naples, Italy. Univ Illinois, Dept Mech & Ind Engn, Urbana, IL 61801 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Albright, JG (reprint author), Texas Christian Univ, Dept Chem, Ft Worth, TX 76129 USA. OI PADUANO, Luigi/0000-0002-1105-4237 NR 28 TC 13 Z9 13 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 2001 VL 232 IS 1-4 BP 273 EP 284 DI 10.1016/S0022-0248(01)01079-X PG 12 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 473KL UT WOS:000171042700035 ER PT J AU Yoon, TS Tetreault, S Bosshard, HE Sweet, RM Sygusch, J AF Yoon, TS Tetreault, S Bosshard, HE Sweet, RM Sygusch, J TI Mosaic spread analysis of Canadian advanced protein crystallization experiment on the Russian space station, Mir SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 8th International Conference on Crystallization of Biological Macromolecules CY MAY 14-19, 2000 CL SANDESTIN, FLORIDA DE growth models; impurities; segregation; X-ray diffraction; microgravity conditions; proteins ID BRAGG REFLECTION PROFILES; CRYSTAL-GROWTH; BIOLOGICAL MACROMOLECULES; TETRAGONAL LYSOZYME; THAUMATIN CRYSTALS; DIFFRACTION DATA; MICROGRAVITY; PERFECTION; QUALITY; IMPURITIES AB Protein crystallization experiments were performed on the Russian space station, Mir, using liquid-liquid interface diffusion. The technique was activated in orbit by the sliding together of two half-wells containing protein and precipitant fluids, respectively. Imperfections in protein crystals were analyzed from rocking curve measurements of the diffracted intensities using synchrotron radiation. Data were collected on microgravity and earth-grown crystals, and 10 different protein pairs were compared. To avoid bias, a double-blind protocol was used throughout the data analysis. Rocking curves for individual reflections were analyzed in terms of crystal domains, each fitted by a three-dimensional Gaussian profile. The results of Gaussian analysis were consistent with domain segregation corresponding to spatially different regions of the protein crystal exhibiting distinct mosaic spreads. When crystals were grown in microgravity the domain mosaic spreads were consistent with five of 10 different proteins exhibiting fewer imperfections, three other proteins showed no significant difference while a remaining two proteins displayed a greater number of apparent imperfections. Ground (earth-grown) controls were also conducted on protein samples flown to assess protein stability as a function of solution storage time prior to protein crystal growth (PCG) activation in microgravity. Protein samples were stored in ground controls at concentrations used to initiate crystallization, and aliquots were analyzed after a 30-day period by dynamic light scattering. Polydispersity estimates indicated that prolonged storage induced heterogeneity in all protein samples. Stable aggregates were present, and they were concentration independent, as shown by resistance to protein sample dilution. A PCG growth model is proposed that takes into account large scale aggregation or self-impurities present during crystal growth and predicts domain segregation. Trapping or rejection of self-impurities using this model can qualitatively explain differences in domain mosaic spreads observed as a function of gravitational environment. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Montreal, Dept Biochem, Montreal, PQ H3C 3J7, Canada. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Sygusch, J (reprint author), Univ Montreal, Dept Biochem, CP 6128,Stn Ctr Villa, Montreal, PQ H3C 3J7, Canada. NR 43 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 2001 VL 232 IS 1-4 BP 520 EP 535 DI 10.1016/S0022-0248(01)01165-4 PG 16 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 473KL UT WOS:000171042700065 ER PT J AU Hanson, BL Harp, JM Kirschbaum, K Parrish, DA Timm, DE Howard, A Pinkerton, AA Bunick, GJ AF Hanson, BL Harp, JM Kirschbaum, K Parrish, DA Timm, DE Howard, A Pinkerton, AA Bunick, GJ TI Macromolecular data collection with cryogenic helium SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 8th International Conference on Crystallization of Biological Macromolecules CY MAY 14-19, 2000 CL SANDESTIN, FLORIDA DE cryocrystallography; high resolution X-ray diffraction; biological macromolecules ID CRYSTAL-STRUCTURE; CRYOCRYSTALLOGRAPHY; MODULATION; CRYOSTAT AB We have previously reported on the use of an open flow helium cryostat in macromolecular crystallographic data collection. This device, developed at the University of Toledo, was used at the APS IMCA beamline to test He as a cryogen and to compare data collected at He temperature to that collected at N-2 temperature. Data were collected on matched crystals of the nucleosome core particle (NCP), fumarylacetoacetate hydrolase (FAH), and the murine monoclonal antibody BV0401 (BV), and other crystals using an Oxford Cryosystems Cryostream and the Toledo Helium Cryostat. In these experiments, crystal lifetime was enhanced by using He as a cryogen. At the end of data collection with NCP, crystals cooled by N-2 were blackened; crystals cooled by He remained clear. A crystal of Mcg light chain dimer (Mcg) had undiminished diffraction in He after 90 min of exposure in the same position. Data improvement is best illustrated in the diffraction data from BY. These data showed an improvement in resolution (1.75-1.48 Angstrom) with a significant enhancement of the intensity for weak data. Data from the NCP showed a similar enhancement in intensity. However, some diffraction data exhibited split reflections at He temperature rendering processing of the data more problematic. One possible explanation for these results is a phase change occurring between 100 K and the 30 K of the helium cold stream. Planned work will characterize this phenomenon and extend the experiments to other crystal systems. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Oak Ridge Grad Sch Genome Sci & Technol, Oak Ridge, TN 37831 USA. Univ Toledo, Dept Chem, Toledo, OH 43606 USA. Indiana Univ, Sch Med, Dept Biochem & Mol Biol, Indianapolis, IN 46202 USA. Argonne Natl Lab, APS, CAT, IMCA, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Hanson, BL (reprint author), Univ Tennessee, Oak Ridge Grad Sch Genome Sci & Technol, POB 2009, Oak Ridge, TN 37831 USA. RI Hanson, Bryant Leif/F-8007-2010; ID, IMCACAT/D-5867-2014; OI Hanson, Bryant Leif/0000-0003-0345-3702; pinkerton, alan/0000-0002-2239-1992 NR 19 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 2001 VL 232 IS 1-4 BP 536 EP 544 PG 9 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 473KL UT WOS:000171042700066 ER PT J AU Segelke, BW AF Segelke, BW TI Efficiency analysis of sampling protocols used in protein crystallization screening SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 8th International Conference on Crystallization of Biological Macromolecules CY MAY 14-19, 2000 CL SANDESTIN, FL DE biocrystallization; solubility; biological macromolecules; lysozyme; proteins ID NAJA-NAJA-NAJA; STRATEGIES AB In an effort to objectively compare the efficiency of protein crystallization screening techniques, a probability model of sampling efficiency is developed and used to calculate sampling efficiencies from experimental data. Three typical sampling protocols (grid screening, footprint screening, and random screening) are used to crystallize each of five proteins (Phospholipase A(2), Thaurnatin, Catalase, Lysozyme, and Ribonuclease B). For each of the three sampling protocols, experiments are chosen from a large set of possible experiments generated by systematic combination of a number of parameters common in crystallization screens. Software has been developed to generate and select from the combinations with each of the three sampling protocols examined in this study. The protocols differ only in the order samples are chosen from the set of possible combinations. Random sampling is motivated by the "Incomplete Factorial" screen (Carter and Carter, J. Biol. Chem. 254 (1979) 12 219); sampling with subsets of four is motivated by the "Footprint" screen (Stura et al., J. Crystal Growth 122 (1992) 273) and sampling with subsets of twenty-four is motivated by the "Grid" screen (McPherson, Prepartion and Analysis of Protein Crystals, Wiley, New York, 1982). For the five proteins examined, random sampling has the greatest average efficiency. Additional benefits of random sampling are discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif San Diego, Dept Chem & Biochem, La Jolla, CA 92093 USA. RP LLNL, BBRP, Biol & Biotechnol Res Program, 7000 E Ave POB 808 L448, Livermore, CA 94551 USA. EM segelke1@llnl.gov NR 17 TC 64 Z9 67 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 EI 1873-5002 J9 J CRYST GROWTH JI J. Cryst. Growth PD NOV PY 2001 VL 232 IS 1-4 BP 553 EP 562 DI 10.1016/S0022-0248(01)01154-X PG 10 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 473KL UT WOS:000171042700068 ER PT J AU Geisz, JF Friedman, DJ Kurtz, S Reedy, RC Barber, G AF Geisz, JF Friedman, DJ Kurtz, S Reedy, RC Barber, G TI Alternative boron precursors for BGaAs epitaxy SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 10th Biennial Workshop on Organometallic Vapor Phase Epitaxy CY MAR 11-15, 2001 CL SAN DIEGO, CALIFORNIA SP Aixtron, Thomas Swan, Emcore Corp, EMF Ltd, Epichem, Rohm & Hass Co DE BGaAs; boron; OMVPE; GaAs ID GROWTH; ALLOYS; FILMS; GAAS AB The organometallic vapor phase epitaxy growth of zinc-blende BxGa1-xAs and BxGa1-x-yInyAs with boron concentrations (x) up to 3-5% has recently been demonstrated using diborane as a boron precursor. Growth of these alloys using diborane is complicated by many factors, such as parasitic gas-phase reactions, highly temperature-dependent boron incorporation, and limited boron incorporation before the onset of structural breakdown. These factors suggest that diborane may not be the best precursor for the growth of these alloys. We compare the use of alternative boron precursors; trimethylboron (TMB), triethylboron (TEB), and boron trifluoride (BF3), with diborane for the OMVPE growth of these boron containing III-V alloys. We find that TMB and BF3, do not result in significant boron incorporation into GaAs. TEB does result in boron incorporation in a manner very similar to diborane. Both diborane and TEB incorporate more efficiently using triethylgallium (TEG) rather than trimethylgallium (TMG), making TEG a preferred source of gallium for BGaAs epitaxy. Using TEB together with TEG, a higher boron composition (x = 4-7%) has been achieved than has been previously reported, but the complicating problems observed with diborane still exist. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Geisz, JF (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 11 TC 11 Z9 11 U1 1 U2 5 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD NOV PY 2001 VL 30 IS 11 BP 1387 EP 1391 DI 10.1007/s11664-001-0188-7 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 491DY UT WOS:000172093800005 ER PT J AU Bourret-Courchesne, ED Yu, KM Benamara, M Liliental-Weber, Z Washburn, J AF Bourret-Courchesne, ED Yu, KM Benamara, M Liliental-Weber, Z Washburn, J TI Mechanisms of dislocation reduction in GaN using an intermediate temperature interlayer SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 10th Biennial Workshop on Organometallic Vapor Phase Epitaxy CY MAR 11-15, 2001 CL SAN DIEGO, CALIFORNIA SP Aixtron, Thomas Swan, Emcore Corp, EMF Ltd, Epichem, Rohm & Hass Co DE GaN; OMVPE; dislocation; TEM; interlayer ID VAPOR-PHASE EPITAXY; GROWN GAN; DENSITY; LAYER; FILMS; SAPPHIRE; MOCVD AB A dramatic reduction of the dislocation density in GaN was obtained by insertion of a single thin interlayer grown at an intermediate temperature (IT-IL) after the initial growth at high temperature. A description of the growth process is presented with characterization results aimed at understanding the mechanisms of reduction in dislocation density. A large percentage of the threading dislocations present in the first GaN epilayer are found to bend near the interlayer and do not propagate into the top layer which grows at higher temperature in a lateral growth mode. TEM studies show that the mechanisms of dislocation reduction are identical to those described for the epitaxial lateral overgrowth process, however a notable difference is the absence of coalescence boundaries. C1 EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Bourret-Courchesne, ED (reprint author), EO Lawrence Berkeley Natl Lab, 1 Cyclotron Rd MS 2-200, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012; Yu, Kin Man/J-1399-2012 OI Yu, Kin Man/0000-0003-1350-9642 NR 19 TC 8 Z9 8 U1 1 U2 4 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD NOV PY 2001 VL 30 IS 11 BP 1417 EP 1420 DI 10.1007/s11664-001-0194-9 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 491DY UT WOS:000172093800011 ER PT J AU Sohn, H Law, KH AF Sohn, H Law, KH TI Damage diagnosis using experimental Ritz vectors SO JOURNAL OF ENGINEERING MECHANICS-ASCE LA English DT Article ID LOAD AB This paper describes an experimental study on the use of Ritz vectors for damage detection of a grid-type bridge model. A new procedure to extract Ritz vectors from experimental modal analysis is proposed and demonstrated using the test structure. The extracted Ritz vectors are then used for the damage detection of the test structure using a Bayesian probabilistic approach. Using appropriate load patterns, Ritz vectors can be made more sensitive to damage than modal vectors. The results indicate that the use of load-dependent Ritz vectors produce better damage diagnoses than the modal vectors. The Bayesian probabilistic approach is shown to give better diagnostic results than commonly used deterministic methods. C1 Los Alamos Natl Lab, Div Engn & Applicat Sci, Engn Anal Grp, Los Alamos, NM 87545 USA. Stanford Univ, Dept Civil & Environm Engn, Stanford, CA 94305 USA. RP Sohn, H (reprint author), Los Alamos Natl Lab, Div Engn & Applicat Sci, Engn Anal Grp, POB 1663, Los Alamos, NM 87545 USA. NR 19 TC 15 Z9 17 U1 0 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-9399 J9 J ENG MECH-ASCE JI J. Eng. Mech.-ASCE PD NOV PY 2001 VL 127 IS 11 BP 1184 EP 1193 DI 10.1061/(ASCE)0733-9399(2001)127:11(1184) PG 10 WC Engineering, Mechanical SC Engineering GA 485MJ UT WOS:000171757900013 ER PT J AU Cremers, DA Ebinger, MH Breshears, DD Unkefer, PJ Kammerdiener, SA Ferris, MJ Catlett, KM Brown, JR AF Cremers, DA Ebinger, MH Breshears, DD Unkefer, PJ Kammerdiener, SA Ferris, MJ Catlett, KM Brown, JR TI Measuring total soil carbon with laser-induced breakdown spectroscopy (LIBS) SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID TO-NOISE RATIOS; ANALYTICAL SPECTROMETRY; FUNDAMENTAL PRINCIPLES; INSTRUMENT; TUTORIAL AB Improving estimates of carbon inventories in soils Is currently hindered by lack of a rapid analysis method for total soil carbon. A rapid, accurate, and precise method that could be used in the field would be a significant benefit to researchers investigating carbon cycling in soils and dynamics of soil carbon in global change processes. We tested a new analysis method for predicting total soil carbon using laser-induced breakdown spectroscopy (LIBS). We determined appropriate spectral signatures and calibrated the method using measurements from dry combustion of a Mollisol from a cultivated plot. From this calibration curve we predicted carbon concentrations in additional samples from the same soil and from an Alfisol collected in a semiarid woodland and compared these predictions with additional dry combustion measurements. Our initial tests suggest that the LIBS method rapidly and efficiently measures soil carbon with excellent detection limits (similar to300 mg/kg), precision (4-5%), and accuracy (3-14%). Initial testing shows that LIBS measurements and dry combustion analyses are highly correlated (adjusted r(2) = 0.96) for soils of distinct morphology, and that a sample can be analyzed by LIBS in less than one minute. The LIBS method is readily adaptable to a field-portable instrument, and this attribute-win combination with rapid and accurate sample analysis-suggests that this new method offers promise for improving measurement of total soil carbon. Additional testing of LIBS is required to understand the effects of soil properties such as texture, moisture content, and mineralogical composition (i.e., silicon content) on LIBS measurements. C1 Los Alamos Natl Lab, Environm Dynam & Spatial Grp, Los Alamos, NM 87545 USA. USDA, NRCS, Nat Lab, Las Cruces, NM 88003 USA. Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Adv Chem Diag & Instrumentat Grp, Los Alamos, NM 87545 USA. New Mexico State Univ, USDA, NRCS, Joranda Expt Range, Las Cruces, NM 88003 USA. RP Ebinger, MH (reprint author), Los Alamos Natl Lab, Environm Dynam & Spatial Grp, MS J495, Los Alamos, NM 87545 USA. EM mhe@lanl.gov RI Breshears, David/B-9318-2009 OI Breshears, David/0000-0001-6601-0058 NR 27 TC 66 Z9 68 U1 0 U2 32 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD NOV-DEC PY 2001 VL 30 IS 6 BP 2202 EP 2206 PG 5 WC Environmental Sciences SC Environmental Sciences & Ecology GA 539HC UT WOS:000174863600043 PM 11790033 ER PT J AU Amthor, JS Koch, GW Willms, JR Layzell, DB AF Amthor, JS Koch, GW Willms, JR Layzell, DB TI Leaf O-2 uptake in the dark is independent of coincident CO2 partial pressure SO JOURNAL OF EXPERIMENTAL BOTANY LA English DT Article DE carbon dioxide; oxygen; respiration; Rumex crispus ID RESPIRATION; LIGHT AB Elevated CO2, in the dark, is sometimes reported to inhibit leaf respiration, with respiration usually measured as CO2 efflux. Oxygen uptake may be a better gauge of respiration because non-respiratory processes can affect dark CO2 efflux in elevated CO2. Two methods of quantifying O-2 uptake indicated that leaf respiration was unaffected by coincident CO2 level in the dark. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. No Arizona Univ, Dept Biol Sci, Flagstaff, AZ 86011 USA. No Arizona Univ, Merriam Powell Ctr Environm Res, Flagstaff, AZ 86011 USA. Queens Univ, Dept Biol, Kingston, ON K7L 3N6, Canada. RP Amthor, JS (reprint author), US DOE, SC-74,19901 Germantown Rd, Germantown, MD 20874 USA. RI Layzell, David/A-9417-2010; Amthor, Jeffrey/F-2696-2016 OI Layzell, David/0000-0003-3085-3189; Amthor, Jeffrey/0000-0002-1410-6100 NR 15 TC 30 Z9 32 U1 1 U2 4 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0957 J9 J EXP BOT JI J. Exp. Bot. PD NOV PY 2001 VL 52 IS 364 BP 2235 EP 2238 PG 4 WC Plant Sciences SC Plant Sciences GA 486YR UT WOS:000171847400019 PM 11604463 ER PT J AU Brown, RS Power, G Beltaos, S AF Brown, RS Power, G Beltaos, S TI Winter movements and habitat use of riverine brown trout, white sucker and common carp in relation to flooding and ice break-up SO JOURNAL OF FISH BIOLOGY LA English DT Article DE winter stranding; ice; flood; habitat; backwater ID JUVENILE COHO SALMON; CUTTHROAT TROUT; ONCORHYNCHUS-CLARKI; BRITISH-COLUMBIA; CARNATION CREEK; RAINBOW-TROUT; STREAM; FALL; FISH; TEMPERATURE AB Movement of radio-tagged riverine brown trout Salmo trutta, while sucker Catostomus commersoni and common carp Cyprinus carpio in the Grand Ri er. Ontario. was minimal during the winter except during periods of high water discharge or the break-up of river ice. Ice break-Up and flooding occur when southern air masses penetrate northwards in winter and as air temperatures increase in spring. Both white suckers and common carp moved the longest distances. generally in a downstream direction. during flooding and ice break-up. Brown trout moved less during these times, All three species had positive relationships between distance ino ed and water discharge. During periods of high water discharge and ice break-up, white Suckers and common carp used backwater habitats more and main channel habitats less than during periods of low water discharge. During high flows, brown trout tended to use runs more,Ind pools less. The break-up of river ice and accompanying flooding resulted in several fish being stranded on the floodplain. Backwater habitats appear to be important areas of refuge for riverine fishes during periods of flooding and ice break-LIP. (C) 2001 the Fisheries Society of the British Isles C1 Univ Waterloo, Dept Biol, Waterloo, ON N2L 3G1, Canada. Environm Canada, Natl Water Res Inst, Burlington, ON L7R 4A6, Canada. RP Brown, RS (reprint author), Pacific NW Natl Lab, Ecol Grp, MSIN K6-85,902 Battelle Blvd,POB 999, Richland, WA 99352 USA. OI Beltaos, Spyros/0000-0002-2247-8588 NR 34 TC 53 Z9 54 U1 2 U2 25 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-1112 J9 J FISH BIOL JI J. Fish Biol. PD NOV PY 2001 VL 59 IS 5 BP 1126 EP 1141 DI 10.1006/jfbi.2001.1725 PG 16 WC Fisheries; Marine & Freshwater Biology SC Fisheries; Marine & Freshwater Biology GA 501ZQ UT WOS:000172718200002 ER PT J AU Bjornstad, BN Fecht, KR Pluhar, CJ AF Bjornstad, BN Fecht, KR Pluhar, CJ TI Long history of pre-Wisconsin, Ice Age cataclysmic floods: Evidence from southeastern Washington State SO JOURNAL OF GEOLOGY LA English DT Article ID GLACIAL LAKE MISSOULA; EASTERN WASHINGTON; CHANNELED SCABLAND; LOESS; JOKULHLAUPS; MAGNITUDES; COLUMBIA AB Cataclysmic Ice Age floods in the Pacific Northwest began as early as 1.5-2.5 Ma, on the basis of an evaluation of surface exposures and recent borehole studies within southeastern Washington. Field evidence suggests at least two episodes of pre-Wisconsin (i.e., > 130 ka) glacial-outburst flooding. A Middle Pleistocene flood is identified by normal magnetic polarity, calcrete-capped deposits that yield maximum Th/U age dates from 200 to >400 ka. The deposits with reversed polarity are correlated to Early Pleistocene (>780 ka) floods. While exposures of pre-Wisconsin deposits are limited because of erosion and/or burial, the record of earlier Pleistocene flooding is preserved within giant flood bars. These bars show incremental growth, representing a composite from cataclysmic floods deposited intermittently through the Pleistocene. In one giant flood bar, up to 100 m thick, deposits interpreted as Matuyama age indicate that the bar had grown to half its present height by 780 ka. Furthermore, Matuyama-age, reversed-polarity flood deposits may be underlain by up to another 15 m of normally magnetized deposits at the base of the flood sequence. This normal-polarity interval appears to be associated with Early Pleistocene cataclysmic floods, perhaps of Olduvai age (>1.77 Ma). Many of the features associated with cataclysmic floods, such as coulees, giant bars, and streamlined loess hills, may have been established during the Early Pleistocene and were only slightly modified by up to hundreds of subsequent flood episodes. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bjornstad, BN (reprint author), Pacific NW Natl Lab, Mailstop K6-81, Richland, WA 99352 USA. NR 48 TC 25 Z9 25 U1 0 U2 8 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0022-1376 J9 J GEOL JI J. Geol. PD NOV PY 2001 VL 109 IS 6 BP 695 EP 713 DI 10.1086/323190 PG 19 WC Geology SC Geology GA 479NR UT WOS:000171410900002 ER PT J AU Gary, SP Goldstein, BE Steinberg, JT AF Gary, SP Goldstein, BE Steinberg, JT TI Helium ion acceleration and heating by Alfven/cyclotron fluctuations in the solar wind SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ALFVEN WAVES; CYCLOTRON-RESONANCE; ALPHA-PARTICLES; CORONAL HOLES; HEAVY-IONS; INSTABILITIES; DISSIPATION; ANISOTROPY; PROTONS; PLASMA AB The interaction between alpha particles and a given magnetic power Spectrum of Alfven/cyclotron fluctuations at propagation parallel to the background magnetic field B-o is examined in a model of a homogeneous, collisionless, magnetized plasma. Exact solutions of the linear Vlasov dispersion equation and second-order theory are used to calculate the wave-particle scattering rates for alpha/proton momentum exchange as well as for proton and alpha heating and anisotropy change. It is well established that alpha velocities are not observed to oscillate when the alpha/proton relative flow speed parallel to B-o matches the phase speed of long-wavelength Alfven waves, the "surfing" speed. Second-order theory predicts that wave-particle scattering is dominated by the relatively short wavelength, relatively low phase speed Alfven/cyclotron fluctuations which have a strong cyclotron resonance with the alphas. Thus the theory predicts that at sufficiently high proton beta the average alpha/proton speed should be observed to be substantially smaller than the surfing speed associated with long-wavelength fluctuations. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Gary, SP (reprint author), Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. NR 40 TC 24 Z9 25 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 2001 VL 106 IS A11 BP 24955 EP 24963 DI 10.1029/2001JA000059 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 490JT UT WOS:000172049300038 ER PT J AU Daughton, W Winske, D Yin, L Gary, SP AF Daughton, W Winske, D Yin, L Gary, SP TI Role of electron physics in slow mode shocks SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID EARTHS DISTANT MAGNETOTAIL; SPACE HOLE MODES; HYBRID SIMULATIONS; GEOMAGNETIC TAIL; DISTRIBUTIONS; ION; RECONNECTION; INSTABILITY; WAVES AB Much of the theoretical understanding concerning the structure and essential properties of the slow mode shock has been obtained from hybrid calculations in which a full kinetic description is used for the ions while the electrons are approximated as a massless adiabatic fluid. Owing to the relatively broad spatial and relatively slow temporal scales of the slow shock, one would expect this approximation to be well justified. In this work we reexamine the importance of electron dynamics using one-dimensional fully kinetic simulations which fully resolve all relevant spatial and temporal electron scales. The resulting shock structure and ion heating are in excellent agreement with hybrid simulations, indicating that the dissipation arising from kinetic electrons is relatively minor. However, electron heating is somewhat larger, and clear non-Maxwellian features are observed. In the upstream region, back-streaming electrons give rise to double-peaked distributions, while in the downstream region, bi-Maxwellian distributions are observed with Te-parallel to > T-e perpendicular to. Although the acceleration mechanism for the back-streaming electrons is not fully understood, we present evidence that resonant wave-particle interactions may play an important role. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Daughton, W (reprint author), Los Alamos Natl Lab, MS B259, Los Alamos, NM 87545 USA. RI Daughton, William/L-9661-2013 NR 32 TC 11 Z9 11 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 2001 VL 106 IS A11 BP 25031 EP 25039 DI 10.1029/2001JA000005 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 490JT UT WOS:000172049300044 ER PT J AU Su, YJ Thomsen, MF Borovsky, JE Lawrence, DJ AF Su, YJ Thomsen, MF Borovsky, JE Lawrence, DJ TI A comprehensive survey of plasmasphere refilling at geosynchronous orbit SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETOSPHERIC ELECTRIC-FIELDS; SEMIKINETIC MODEL; DENSITY; IONOSPHERE; TEMPERATURE; PLASMAPAUSE; SPACECRAFT; ANALYZER; SHEET; IONS AB Plasmasphere refilling is one of the most fundamental examples of ionosphere-magnetosphere coupling. Geosynchronous low-energy ion measurements are particularly useful in addressing this issue. In this survey we collect almost 11 satellite years of data, from January 1990 to September 2000, from Los Alamos magnetospheric plasma analyzers on board five satellites. The data are sorted according to the level of magnetospheric activity, local time, season, and solar cycle phase for a comprehensive examination of the early-time refilling rate. These statistical results indicate that the early-time refilling rate increases with increasing geomagnetic activity. Additionally, the early-time refilling rate at low solar activity is about a factor of 1.5 - 2 higher than that at high solar activity. This may be related to the higher ionospheric neutral hydrogen density at solar minimum. Moreover, when the geomagnetic activity index is higher than 3, the early-time refilling rate is observed to be slightly higher during the seasonal equinox periods than at solstice, but no seasonal variation is found at low geomagnetic activity. The late-time refilling rate is also examined during intervals of prolonged geomagnetic quiet. The refilling process is not linear as a function of time: The early-time refilling rate ranges between 2.5 and 6.5 cm(-3) d(-1), while the late-time refilling rate is found to be similar to 10 - 25 cm(-3) d(-1). The late-time refilling rate is also anticorrelated with solar activity. The plasmasphere at 3 geosynchronous orbit is observed to reach a maximum density at similar to 100 - 200 cm(-3). C1 Los Alamos Natl Lab, Space & Atmospher Sci grp, Los Alamos, NM 87545 USA. RP Su, YJ (reprint author), Los Alamos Natl Lab, Space & Atmospher Sci grp, NIS-1,MS-D466, Los Alamos, NM 87545 USA. RI Lawrence, David/E-7463-2015 OI Lawrence, David/0000-0002-7696-6667 NR 37 TC 27 Z9 27 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 2001 VL 106 IS A11 BP 25615 EP 25629 DI 10.1029/2000JA000441 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 490JT UT WOS:000172049300089 ER PT J AU Choueiri, EY Oraevsky, VN Dokukin, VS Volokitin, AS Pulinets, SA Ruzhin, YY Afonin, VV AF Choueiri, EY Oraevsky, VN Dokukin, VS Volokitin, AS Pulinets, SA Ruzhin, YY Afonin, VV TI Observations and modeling of neutral gas releases from the APEX satellite SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SPACE AB Results from experiments of neutral xenon gas releases in the ionosphere are presented. The releases were made from the scientific satellite APEX, which had various plasma and field diagnostics. An enhancement of HF wave activity over a broad band (0.1-10 MHz) is shown to occur during releases made in the sunlight at high pitch angles to the magnetic field. No changes of plasma density were detected, but electron temperature measurements indicate electron energy enhancements during the releases. Theoretical calculations based on the conditions of the APEX releases show that charge-exchange collisions and elastic scattering of the injected Xe neutrals by the ambient plasma can lead to an ion beam instability that may account for the observed wave and electron energy enhancements. The interaction is akin to the critical ionization velocity effect. We calculate that because of the low injection density, this turbulence-fueled ionization should have a low yield (<1%), which may explain the lack of detectable plasma density enhancement. C1 Princeton Univ, Appl Phys Grp, Elect Propuls & Plasma Dynam Lab, Princeton, NJ 08544 USA. Inst Terr Magnetism Ionosphere & Radiowave Propag, IZMIRAN, Troitsk 142092, Moscow Region, Russia. Space Res Inst, Moscow 117810, Russia. RP Choueiri, EY (reprint author), Princeton Univ, Appl Phys Grp, Elect Propuls & Plasma Dynam Lab, Princeton, NJ 08544 USA. RI Pulinets, Sergey/F-7462-2011 OI Pulinets, Sergey/0000-0003-3944-6686 NR 16 TC 5 Z9 15 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 2001 VL 106 IS A11 BP 25673 EP 25681 DI 10.1029/2001JA000040 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 490JT UT WOS:000172049300093 ER PT J AU Ingraham, JC Cayton, TE Belian, RD Christensen, RA Friedel, RHW Meier, MM Reeves, GD Tuszewski, M AF Ingraham, JC Cayton, TE Belian, RD Christensen, RA Friedel, RHW Meier, MM Reeves, GD Tuszewski, M TI Substorm injection of relativistic electrons to geosynchronous orbit during the great magnetic storm of March 24, 1991 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ENERGETIC PARTICLE MEASUREMENTS; PLASMA SHEET ION; RADIATION BELT; SOLAR-WIND; SPECTRAL CHARACTERISTICS; GEOMAGNETIC CONDITIONS; INNER MAGNETOSPHERE; JOVIAN ELECTRONS; DRIFT ECHOES; ACCELERATION AB The great March 1991 magnetic storm and the immediately preceding solar energetic particle event (SEP) were among the largest observed during the past solar cycle, and have been the object of intense study. We investigate here, using data from eight satellites, the very large delayed buildup of relativistic electron flux in the outer zone during a 1.5-day period beginning 2 days after onset of the main phase of this storm. A notable feature of the March storm is the intense substorm activity throughout the period of the relativistic flux buildup, and the good correlation between some temporal features of the lower-energy substorm-injected electron flux and the relativistic electron flux at geosynchronous orbit. Velocity dispersion analysis of these fluxes between geosynchronous satellites near local midnight and local noon shows evidence that both classes of electrons arrive at geosynchronous nearly simultaneously within a few hours of local midnight. From this we conclude that for this storm period the substorm inductive electric field transports not only the usual (50-300 keV) substorm electrons but also the relativistic (0.3 to several MeV) electrons to geosynchronous orbit. A simplified calculation of the electron epsilon x B and gradient/curvature drifts indicates that sufficiently strong substorm dipolarization inductive electric fields (greater than or equal to 10 mV/m) could achieve this, provided sufficient relativistic electrons are present in the source region. Consistent with this interpretation, we find that the injected relativistic electrons have a pitch angle distribution that is markedly peaked perpendicular to the magnetic field. Furthermore, the equatorial phase space density at geosynchronous orbit (L = 6.7) is greater than it is at GPS orbit at the equator (L = 4.2) throughout this buildup period, indicating that a source for the relativistic electrons lies outside geosynchronous orbit during this time. Earthward transport of the relativistic electrons by large substorm dipolarization fields, since it is unidirectional, would constitute a strong addition to the transport by radial diffusion and, when it occurs, could result in unusually strong relativistic fluxes, as is reported here for this magnetic storm. C1 Los Alamos Natl Lab, NIS Div, Los Alamos, NM 87544 USA. RP Ingraham, JC (reprint author), Los Alamos Natl Lab, NIS Div, MS D436,NIS-2, Los Alamos, NM 87544 USA. RI Friedel, Reiner/D-1410-2012; Reeves, Geoffrey/E-8101-2011 OI Friedel, Reiner/0000-0002-5228-0281; Reeves, Geoffrey/0000-0002-7985-8098 NR 73 TC 29 Z9 29 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 2001 VL 106 IS A11 BP 25759 EP 25776 DI 10.1029/2000JA000458 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 490JT UT WOS:000172049300099 ER PT J AU Lui, ATY Cheng, CZ AF Lui, ATY Cheng, CZ TI Resonance frequency of stretched magnetic field lines based on a self-consistent equilibrium magnetosphere model SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID STANDING HYDROMAGNETIC-WAVES; GEOMAGNETIC-FIELD; SHEAR-ALFVEN; NIGHTSIDE MAGNETOSPHERE; AURORAL ARCS; RING CURRENT; OSCILLATIONS; PRESSURE; NUMBER AB Field line resonance (FLR) has the potential to account for magnetic and electric oscillations observed near the equatorial region of the magnetosphere and on the ground associated with auroral arcs. Previous theoretical works based on dipolar field lines give frequencies too high to match with the observed frequencies when typical mass density is used. Inclusion of magnetic field stretching from empirical magnetic field models brings good agreement, but these models have no assurance of specifying an equilibrium magnetosphere. In this paper we present, for the first time, quantitative results of the resonance frequencies for the shear Alfven and slow mode branches of FLR threading the auroral zone for field lines stretched to various distances in the nightside based on a self-consistent equilibrium magnetosphere. The calculation is done in two steps. For a given degree of field line stretching we first obtain an MHD equilibrium magnetosphere with a finite temperature through a self-consistent solution of the Grad-Shafranov equation. We then solve for FLR frequencies of stretched magnetic field lines in the equilibrium magnetosphere according to the MHD theory of FLR. The results show that field line stretching can lead to low frequencies of FLR as observed without invoking unrealistically high mass density. Dependent on the wave mode and the amount of field line stretching, the FLR frequencies found in this calculation differ from those for a simple magnetic dipole of the Earth by varying degrees, from agreement within a factor of 2 to a disparity of greater than a factor of 10. C1 Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Johns Hopkins Univ, Appl Phys Lab, Johns Hopkins Rd, Laurel, MD 20723 USA. EM tony.lui@jhuapl.edu RI Cheng, Chio/K-1005-2014 NR 31 TC 18 Z9 18 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 2001 VL 106 IS A11 BP 25793 EP 25802 DI 10.1029/2001JA000113 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 490JT UT WOS:000172049300101 ER PT J AU Bergman, O Okawa, Y Brodie, J AF Bergman, O Okawa, Y Brodie, J TI The stringy quantum Hall fluid SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE Chern-Simons theories; D-branes ID OPEN WILSON LINES; GAUGE-THEORY; CHERN-SIMONS; BRANES; SUPERGRAVITY; DIMENSIONS; DYNAMICS; CREATION; MODEL AB Using branes in massive type IIA string theory, and a novel decoupling limit, we provide an explicit correspondence between non-commutative Chern-Simons theory and the fractional quantum Hall fluid. The role of the electrons is played by D-particles, the background magnetic field corresponds to a RR 2-form flux, and the two-dimensional fluid is described by non-commutative D2-branes. The filling fraction is given by the ratio of the number of D2-branes and the number of D8-branes, and therefore by the ratio rank/level of the Chern-Simons gauge theory. Quasiparticles and quasiholes are realized as endpoints of fundamental strings on the D2-branes, and are found to possess fractional D-particle charges and fractional statistics. C1 CALTECH, Pasadena, CA 91125 USA. Univ So Calif, CIT, Ctr Theoret Phys, Los Angeles, CA USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA. RP CALTECH, Pasadena, CA 91125 USA. EM bergman@theory.caltech.edu; okawa@theory.caltech.edu; brodie@SLAC.Stanford.edu NR 43 TC 38 Z9 38 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD NOV PY 2001 IS 11 AR 019 PG 23 WC Physics, Particles & Fields SC Physics GA 527EP UT WOS:000174174000019 ER PT J AU Bern, Z De Freitas, A Ghinculov, A Wong, H Dixon, L AF Bern, Z De Freitas, A Ghinculov, A Wong, H Dixon, L TI QCD and QED corrections to light-by-light scattering SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE QCD; NLO computations; hadronic colliders ID ENERGY COLLISION PROCESSES; PHOTON-PHOTON SCATTERING; QUANTUM ELECTRODYNAMICS; DELBRUCK SCATTERING; GAMMA-GAMMA; BOX INTEGRALS; GAUGE-THEORY; DIMENSIONS; AMPLITUDES; POSITRON AB We present the QCD and QED corrections to the fermion-loop contributions to light-by-light scattering, gammagamma -->gammagamma, in the ultrarelativistic limit where the kinematic invariants are much larger than the masses of the charged fermions. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. EM bern@physics.ucla.edu; freitas@physics.ucla.edu; adriangh@physics.ucla.edu; hlwong@physics.ucla.edu; lance@slac.stanford.edu NR 56 TC 36 Z9 36 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD NOV PY 2001 IS 11 AR 031 PG 18 WC Physics, Particles & Fields SC Physics GA 527EP UT WOS:000174174000031 ER PT J AU Brodie, J AF Brodie, J TI D-branes in massive IIA and solitons in Chern-Simons theory SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE solitons monopoles and instantons; Chern-Simons theories; brane; dynamics in gauge theories; anomalies in field and string theories ID 3-DIMENSIONAL GAUGE DYNAMICS; CHIRAL-SYMMETRY; STRING THEORY; CONFIGURATIONS; SUPERGRAVITY; SUPERSTRINGS; DIMENSIONS; CREATION; DUALITY; LATTICE AB We investigate D2-branes, D4-branes, and D6-branes parallel to D8-branes. The low energy world volume theory on the branes is non-supersymmetric Chern-Simons theory. We indentify the fundamental strings as the anyons of the 2+1 Chern-Simons theory and the D0-branes as solitons. The Chern-Simons theory with a boundary is modeled using a brane box made from NS5-brane. The brane set-up provides for a graphical description of anomaly inflow. We also model the 4+1 Chern-Simons theory using branes and conjecture that D4-branes with a boundary describes a supersymmetric version of Kaplan's theory of chiral fermions. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM brodie@slac.stanford.edu NR 36 TC 3 Z9 3 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD NOV PY 2001 IS 11 AR 014 PG 22 WC Physics, Particles & Fields SC Physics GA 527EP UT WOS:000174174000014 ER PT J AU Evslin, J Murayama, H Varadarajan, U Wang, JE AF Evslin, J Murayama, H Varadarajan, U Wang, JE TI Dial M for flavor symmetry breaking SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE duality in gauge field theories; M-theory; D-branes; brane dynamics in gauge theories ID ELECTRIC-MAGNETIC DUALITY; SUPERSYMMETRIC QCD; GAUGE-THEORIES; DYNAMICS; BRANES; CONFINEMENT; MONOPOLES AB We introduce a realization of Seiberg duality in MQCD that does not involve moving branes. Using related arguments in M-theory and IIA, we investigate the flavor symmetry breaking via flavored magnetic monopole condensation of hep-th/0005076. We verify our results by considering visualizations of M5-branes corresponding to N = 2 vacua which survive soft breaking by an adjoint mass term. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ernest Orlando Lawrence Berkley Natl Lab, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM jarah@uclink4.berkeley.edu; murayama@lbl.gov; udayv@socrates.berkeley.edu; hllywd2@physics.berkeley.edu RI Murayama, Hitoshi/A-4286-2011 NR 24 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD NOV PY 2001 IS 11 AR 030 PG 26 WC Physics, Particles & Fields SC Physics GA 527EP UT WOS:000174174000030 ER PT J AU Kaplan, DE Tait, TMP AF Kaplan, DE Tait, TMP TI New tools for fermion masses from extra dimensions SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE extra large dimensions; supersymmetry breaking; supersymmetric standard model ID STANDARD MODEL; QUARK MASSES; CP VIOLATION; PROTON DECAY; HIERARCHY; BREAKING; UNIFICATION; GENERATIONS; MILLIMETER AB We present models in which the observed fermion masses and mixings are generated by dynamically localizing the three generations of matter in a flat compact extra dimension. We first construct models assuming the hierarchy problem is addressed by the existence of large extra dimensions, i.e. the fundamental scale is not far above a TeV and supersymmetry is not imposed. These models are compactified, chiral, and don't require fine-tuning to generate the top mass. Limits on the compactification scale based on flavor-changing neutral currents are relaxed compared to those on existing models. We then supersymmetrize some of these models. Using N = 1 superspace language in extra dimensions, we find space-dependent flat directions which can be used to localize fields. Finally, we discuss methods of breaking supersymmetry and the impact of these models on the superpartner spectrum. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM dkaplan@slac.stanford.edu; tait@anl.gov NR 48 TC 97 Z9 97 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD NOV PY 2001 IS 11 AR 051 DI 10.1088/1126-6708/2001/11/051 PG 29 WC Physics, Particles & Fields SC Physics GA 527EP UT WOS:000174174000051 ER PT J AU Campillo, G Berger, A Osorio, J Pearson, JE Bader, SD Baca, E Prieto, P AF Campillo, G Berger, A Osorio, J Pearson, JE Bader, SD Baca, E Prieto, P TI Substrate dependence of magnetic properties of La0.67Ca0.33MnO3 films SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE manganites; thin films; epitaxial strain; magnetic order; phase transitions; Curie temperature ID LOW-FIELD MAGNETORESISTANCE; PR0.67SR0.33MNO3 THIN-FILMS; MANGANITE FILMS; STRAIN; LA1-XCAXMNO3; BEHAVIOR; STRESS; GROWTH; MICROSTRUCTURE; LA0.7CA0.3MNO3 AB We investigate the magnetic properties of 200-nm thick La0.67Ca0.33MnO3 films, which were grown under identical conditions onto five single crystal substrates: SrTiO3(001), LaAlO3(001), MgO(001), NdGaO3(001) and Si(111). The films exhibit a strong substrate dependence of the magnetic properties, including the coercive field, remanent magnetization and Curie temperature Tc. The TC distribution was determined for each film, The upper cut-off value for the distribution is found to be virtually identical in all samples, even though the distribution width itself varies by almost an order of magnitude. The results are attributed predominantly to the degree of sample homogeneity, and are discussed in terms of strain-induced growth mode differences. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Valle, Dept Fis, Cali 25360, Colombia. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Berger, A (reprint author), IBM, Almaden Res Ctr, 650 Harry Rd,K63-E3, San Jose, CA 95120 USA. RI Bader, Samuel/A-2995-2013; Campillo, Gloria/A-8299-2013; Berger, Andreas/D-3706-2015 OI Berger, Andreas/0000-0001-5865-6609 NR 39 TC 45 Z9 46 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD NOV PY 2001 VL 237 IS 1 BP 61 EP 68 DI 10.1016/S0304-8853(01)00482-6 PG 8 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 492PA UT WOS:000172175700010 ER PT J AU Jacobus, K DeVor, RE Kapoor, SG Peascoe, RA AF Jacobus, K DeVor, RE Kapoor, SG Peascoe, RA TI Predictive model for the full biaxial surface and subsurface residual stress profiles from turning SO JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID STAINLESS-STEEL AB A model to predict the fill biaxial surface and subsurface residual stresses from the turning process is presented. The model formulation includes thermomechanical coupling, plastic heating, frictional heating, convection, conduction, thermal softening and strain hardening. Calibration and validation of the model are undertaken. The predictive model stands as a tool both to optimize the turning process based on the resulting residual stresses and also to gain an in-depth understanding of the physics of residual stress development from the turning process. In addition, thorough analysis of the experimental results reveals insight into the effects of feed and depth of cut on the surface and subsurface machining-induced residual stresses. C1 Univ Illinois, Dept Mech & Ind Engn, Urbana, IL 61801 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Jacobus, K (reprint author), Univ Illinois, Dept Mech & Ind Engn, Urbana, IL 61801 USA. NR 17 TC 8 Z9 10 U1 1 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1087-1357 J9 J MANUF SCI E-T ASME JI J. Manuf. Sci. Eng.-Trans. ASME PD NOV PY 2001 VL 123 IS 4 BP 537 EP 546 DI 10.1115/1.1372197 PG 10 WC Engineering, Manufacturing; Engineering, Mechanical SC Engineering GA 494WC UT WOS:000172308000001 ER PT J AU Vasinonta, A Beuth, JL Griffith, ML AF Vasinonta, A Beuth, JL Griffith, ML TI A process map for consistent build conditions in the solid freeform fabrication of thin-walled structures SO JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID MOLTEN DROPLET SOLIDIFICATION; FUSED DEPOSITION; METAL DROPLET; PREDICTION; ISSUES AB In solid freeform fabrication (SFF) processes involving thermal deposition, thermal control of the process is critical for obtaining consistent build conditions and in limiting residual stress-induced warping of parts. In this research, a nondimensionalized plot (termed a process map) is developed from numerical models of laser-based material deposition of thin-walled structures. This process map quantifies the effects of changes in wall height, laser power deposition speed and part preheating on melt pool length, which is an essential process parameter to control in order to obtain consistent build conditions. The principal application of this work is to the Laser Engineered Net Shaping (LENS) process under development at Sandia Laboratories; however, the general approach and a subset of the presented results are applicable to any SFF process involving a moving heat source. Procedures are detailed for using the process map to predict melt pool length and predictions are compared against experimentally measured melt pool lengths for stainless steel deposition in the LENS process. C1 Carnegie Mellon Univ, Dept Mech Engn, Pittsburgh, PA 15213 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Vasinonta, A (reprint author), Carnegie Mellon Univ, Dept Mech Engn, 5000 Forbes Ave, Pittsburgh, PA 15213 USA. NR 30 TC 36 Z9 38 U1 4 U2 27 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1087-1357 J9 J MANUF SCI E-T ASME JI J. Manuf. Sci. Eng.-Trans. ASME PD NOV PY 2001 VL 123 IS 4 BP 615 EP 622 DI 10.1115/1.1370497 PG 8 WC Engineering, Manufacturing; Engineering, Mechanical SC Engineering GA 494WC UT WOS:000172308000011 ER PT J AU Cheng, JY Gibson, JM Jacobson, DC AF Cheng, JY Gibson, JM Jacobson, DC TI Observations of structural order in ion-implanted amorphous silicon SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID SEMICONDUCTORS AB Medium-range order in ion-implanted amorphous silicon has been observed using fluctuation electron microscopy. In fluctuation electron microscopy, variance of dark-field image intensity contains the information of high-order atomic correlations, primarily in medium-range order length scale (1-3 nm). Thermal annealing greatly reduces the order and leaves a random network. It appears that the free energy change previously observed on relaxation may therefore be associated with randomization of the network. In this paper, we discuss the origin of the medium-range order during implantation, which can be interpreted as a paracrystalline state, that is, a disordered network enclosing compacts of highly topologically ordered grains on the length scale of 1-3 nm with significant strain fields. C1 Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Bell Lab, Lucent Technol, Murray Hill, NJ 07974 USA. RP Cheng, JY (reprint author), Univ Illinois, Dept Mat Sci & Engn, 1304 W Green St, Urbana, IL 61801 USA. RI Gibson, Murray/E-5855-2013 OI Gibson, Murray/0000-0002-0807-6224 NR 17 TC 19 Z9 19 U1 0 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD NOV PY 2001 VL 16 IS 11 BP 3030 EP 3033 DI 10.1557/JMR.2001.0416 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 489YL UT WOS:000172020600003 ER PT J AU Kramer, DE Volinsky, AA Moody, NR Gerberich, WW AF Kramer, DE Volinsky, AA Moody, NR Gerberich, WW TI Substrate effects on indentation plastic zone development in thin soft films SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID WEAR-RESISTANT COATINGS; WT-PERCENT-SI; MECHANICAL-PROPERTIES; SINGLE-CRYSTAL; MICROINDENTATION MECHANICS; HARDNESS; SILICON; DEFORMATION; LOAD; MICROSCOPY AB Plastic zone evolution in Al-2 wt% Si metal films on silicon and sapphire substrates was studied using nanoindentation and atomic force microscopy (AFM). AFM was used to measure the extent of plastic pileup, which is a measure of the plastic zone radius in the film. It was found that the plastic zone size develops in a self-similar fashion with increasing indenter penetration when normalized by the contact radius, regardless of film hardness or underlying substrate properties. This behavior was used to develop a hardness model that uses the extent of the plastic zone radius to calculate a core region within the indenter contact that is subject to an elevated contact pressure. AFM measurements also indicated that as film thickness decreases, constraint imposed by the indenter and substrate traps the film thereby reducing the pileup volume. C1 Natl Inst Stand & Technol, Div Met, Gaithersburg, MD 20899 USA. Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. Sandia Natl Labs, Div Mat Reliabil, Livermore, CA 94551 USA. RP Kramer, DE (reprint author), Natl Inst Stand & Technol, Div Met, Gaithersburg, MD 20899 USA. RI Volinsky, Alex/A-7974-2009; OI Volinsky, Alex/0000-0002-8520-6248 NR 37 TC 59 Z9 61 U1 1 U2 13 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD NOV PY 2001 VL 16 IS 11 BP 3150 EP 3157 DI 10.1557/JMR.2001.0434 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 489YL UT WOS:000172020600021 ER PT J AU Nieh, TG Jankowski, AF Koike, J AF Nieh, TG Jankowski, AF Koike, J TI Processing and characterization of hydroxyapatite coatings on titanium produced by magnetron sputtering SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CALCIUM-PHOSPHATE COATINGS; METALS AB Hydroxyapatite (HA) coatings with different thicknesses were produced on Ti and Si substrates using the radio frequency magnetron sputtering method. The mechanical properties, for example, modulus and hardness, of the coatings were measured using nanoindentation. The measured values of modulus and hardness were close to the upper limit of that reported for bulk HA, indicating a fully dense structure. Interfacial strengths between the HA coatings and substrates were also evaluated using a nanoscratch technique. The HA-Ti interface appeared to be stronger than the HA-Si interface. The microstructures of the HA coating and the HA-Ti interface were examined using high-resolution electron microscopy. Chemical compositions of the HA coating and the HA-Ti interface were also analyzed using x-ray energy dispersive spectrometer and electron energy loss spectroscopy. The results indicated that the strong HA-Ti bonding is associated with an outward diffusion of Ti into HA layer and concomitant formation of TiO2 at or near the interface. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Tohoku Univ, Dept Mat Sci, Aoba Ku, Sendai, Miyagi 9808579, Japan. RP Lawrence Livermore Natl Lab, L-350,POB 808, Livermore, CA 94551 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 21 TC 50 Z9 50 U1 1 U2 9 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0884-2914 EI 2044-5326 J9 J MATER RES JI J. Mater. Res. PD NOV PY 2001 VL 16 IS 11 BP 3238 EP 3245 DI 10.1557/JMR.2001.0446 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 489YL UT WOS:000172020600033 ER PT J AU Xu, Y Chumbley, LS Weigelt, GA Laabs, FC AF Xu, Y Chumbley, LS Weigelt, GA Laabs, FC TI Analysis of interdiffusion of Dy, Nd, and Pr in Mg SO JOURNAL OF MATERIALS RESEARCH LA English DT Article AB The diffusion characteristics of Mg-rare-earth diffusion couples were studied. Cylinders of pure Mg and rare earth (Dy, Nd, and Pr) were abutted and annealed at 500 degreesC for 100 h or 300 h. Point-by-point composition profiles were collected starting in pure Mg, across the diffusion zone, and ending in the pure rare earth, using energy dispersive x-ray spectroscopy with a scanning electron microscope. The intermetallic phases that resulted due to diffusion were identified and compared to existing phase diagrams, for which the data is limited. For each diffusion couple, a plot of concentration versus distance perpendicular to the original plane of contact was obtained and analyzed using the Boltzman-Matano method. The interdiffusion coefficients for each set of phases were then calculated. The results show that diffusion through the intermetallic phases is much slower than is expected in a solid solution. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Mat Sci & Engn Dept, Ames, IA 50011 USA. RP Xu, Y (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 11 TC 6 Z9 7 U1 1 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD NOV PY 2001 VL 16 IS 11 BP 3287 EP 3292 DI 10.1557/JMR.2001.0452 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 489YL UT WOS:000172020600039 ER PT J AU Abraham, DP Richardson, JW McDeavitt, SM AF Abraham, DP Richardson, JW McDeavitt, SM TI Microscopy and neutron diffraction study of a zirconium-8 wt% stainless steel alloy SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID BETA AB The electrometallurgical treatment of zirconium-based and Zircaloy-clad spent nuclear fuels will yield a metal waste form. The baseline composition for the waste form is zirconium-8 wt% stainless steel (Zr-8SS). The microstructure of the Zr-8SS alloy has been studied by scanning electron microscopy, energy dispersive spectroscopy, and neutron diffraction. The phases present in the as-cast alloy include Zr(alpha), Zr-3(Fe,Ni), Zr-2(Fe,Ni), Zr-2(Fe,Cr), and Zr(Fe,Cr)(2); a solidification sequence has been proposed to explain the formation and morphology of these phases. Alloy phase stability has been studied by thermal aging at 780 degreesC for periods up to 30 days. The phase changes that occur during thermal aging include an increase in Zr-3(Fe,Ni) and a decrease in Zr-2(Fe,Ni) content; reaction mechanisms have been proposed to explain these changes. The lattice parameters of alloy phases have been determined by neutron diffraction and found to be in agreement with those previously reported for similar phases. This study of alloy microstructures is the first step towards understanding the actinide and fission product distribution and predicting the corrosion behavior of the Zr-8SS metal waste form. (C) 2001 Kluwer Academic Publishers. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Abraham, DP (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 32 TC 4 Z9 4 U1 1 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD NOV PY 2001 VL 36 IS 21 BP 5143 EP 5154 DI 10.1023/A:1012433526079 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 481VJ UT WOS:000171540900013 ER PT J AU Zhang, XF Sixta, ME Chen, D De Jonghe, LC AF Zhang, XF Sixta, ME Chen, D De Jonghe, LC TI Nano-precipitation in hot-pressed silicon carbide SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID GRAIN-SIZE DEPENDENCE; NITRIDE CERAMICS; FRACTURE ENERGY; CREEP; BEHAVIOR; ALUMINUM; PHASE; FILM AB Heat treatments at 1300 degreesC, 1400 degreesC, 1500 degreesC, and 1600 degreesC in Ar were found to produce nanoscale precipitates in hot-pressed silicon carbide containing aluminum, boron, and carbon sintering additives (ABC-SiC). The precipitates were studied by transmission electron microscopy (TEM) and nano-probe energy-dispersive X-ray spectroscopy (nEDS). The precipitates were plate-like in shape, with a thickness, length and separation of only a few nanometers, and their size coarsened with increasing annealing temperature, accompanied by reduced number density. The distribution of the precipitates was uniform inside the SiC grains, but depleted zones were observed in the vicinity of the SiC grain boundaries. A coherent orientation relationship between the precipitates and the SiC matrix was found. Combined high-resolution electron microscopy, computer simulation, and nEDS identified an Al4C3-based structure and composition for the nano-precipitates. Most Al ions in SiC lattice exsolved as precipitates during the annealing at 1400 to 1500 degreesC. Formation mechanism and possible influences of the nanoscale precipitates on mechanical properties are discussed. (C) 2001 Kluwer Academic Publishers. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Zhang, XF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 29 TC 7 Z9 7 U1 1 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD NOV PY 2001 VL 36 IS 22 BP 5447 EP 5455 DI 10.1023/A:1012429613824 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA 484ZQ UT WOS:000171727000021 ER PT J AU Xavier, JB Schnell, A Wuertz, S Palmer, R White, DC Almeida, JS AF Xavier, JB Schnell, A Wuertz, S Palmer, R White, DC Almeida, JS TI Objective threshold selection procedure (OTS) for segmentation of scanning laser confocal microscope images SO JOURNAL OF MICROBIOLOGICAL METHODS LA English DT Article DE objective threshold selection; confocal laser scanning microscopy; robust automatic threshold selection ID BIOFILMS; COMMUNITY; GROWTH AB The determination of volumes and interface areas from confocal laser scanning microscopy (CLSM) images requires the identification of component objects by segmentation. An automated method for the determination of segmentation thresholds for CLSM imaging of biofilms was developed. The procedure, named objective threshold selection (OTS), is a three-dimensional development of the approach introduced by the popular robust automatic threshold selection (RATS) method. OTS is based on the statistical properties of local gray-values and gradients in the image, By characterizing the dependence between a volumetric feature and the intensity threshold used for image segmentation, the former can be determined with an arbitrary confidence level, with no need for user intervention. The identification of an objective segmentation procedure renders the possibility for the full automation of volume and interfacial area measurement. Images from two distinct biofilm systems, acquired using different experimental techniques and instrumental setups were segmented by OTS to determine biofilm volume and interfacial area. The reliability of measurements for each case was analyzed to identify optimal procedure for image acquisition. The automated OTS method was shown to reproduce values obtained manually by an experienced operator. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Med Univ S Carolina, Dept Biometry & Epidemiol, Charleston, SC 29425 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. Natl Inst Dent Craniofacial Res, NIH, Oral Infect & Immun Branch, Bethesda, MD 20892 USA. Tech Univ Munich, Inst Water Qual Control & Waste Management, D-85748 Garching, Germany. Univ Nova Lisboa, Inst Tecnol Quim & Biol, P-2780 Oeiras, Portugal. RP Almeida, JS (reprint author), Med Univ S Carolina, Dept Biometry & Epidemiol, 135 Rutledge Ave,POB 250551, Charleston, SC 29425 USA. NR 23 TC 35 Z9 36 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-7012 J9 J MICROBIOL METH JI J. Microbiol. Methods PD NOV PY 2001 VL 47 IS 2 BP 169 EP 180 DI 10.1016/S0167-7012(01)00298-6 PG 12 WC Biochemical Research Methods; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA 481GB UT WOS:000171510600004 PM 11576681 ER PT J AU Pan, JW Telang, FW Lee, JH de Graaf, RA Rothman, DL Stein, DT Hetherington, HP AF Pan, JW Telang, FW Lee, JH de Graaf, RA Rothman, DL Stein, DT Hetherington, HP TI Measurement of beta-hydroxybutyrate in acute hyperketonemia in human brain SO JOURNAL OF NEUROCHEMISTRY LA English DT Article DE brain; beta-hydroxybutyrate; ketone body; lactate; magnetic resonance spectroscopy ID KETONE-BODY UTILIZATION; RAT-BRAIN; STARVATION; GLUCOSE; BODIES AB We report the measurement of D-p-hydroxybutyrate (BHB) in the brains of six normal adult subjects during acute infusions of BHB. We used high field in vivo H-1 magnetic resonance (MR) spectroscopy in the occipital lobe in conjunction with an acute infusion protocol to elevate plasma BHB levels from overnight fasted levels (0.20 +/- 0.10 mm) to a steady state value of 2.12 +/- 0.30 mm. At this level of hyperketonemia, we determined a tissue BHB level of 0.24 +/- 0.04 mm. No increases in brain lactate levels were seen in these data. The concentrations of BHB and lactate were both considerably lower in comparison with previous data acquired in fasted adult subjects. This suggests that up-regulation of the monocarboxylic acid transporter occurs with fasting. C1 Yeshiva Univ Albert Einstein Coll Med, Dept Neurol, Bronx, NY 10461 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Yale Univ, Sch Med, New Haven, CT USA. RP Pan, JW (reprint author), Yeshiva Univ Albert Einstein Coll Med, Dept Neurol, 1300 Morris Pk Ave, Bronx, NY 10461 USA. RI Lee, Jing-Huei/J-3978-2016 OI Lee, Jing-Huei/0000-0001-9921-7629 FU NCRR NIH HHS [1MO1RR12248]; NINDS NIH HHS [P01NS-39092] NR 19 TC 30 Z9 30 U1 0 U2 2 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-3042 J9 J NEUROCHEM JI J. Neurochem. PD NOV PY 2001 VL 79 IS 3 BP 539 EP 544 DI 10.1046/j.1471-4159.2001.00575.x PG 6 WC Biochemistry & Molecular Biology; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA 488UM UT WOS:000171954300008 PM 11701757 ER PT J AU Voyles, PM Gerbi, JE Treacy, MMJ Gibson, JM Abelson, JR AF Voyles, PM Gerbi, JE Treacy, MMJ Gibson, JM Abelson, JR TI Increased medium-range order in amorphous silicon with increased substrate temperature SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 8th International Conference on the Structure on Non-Crystalline Materials (NCM 8) CY AUG 06-11, 2000 CL UNIV WALES, ABERYSTWYTH, WALES SP Corning Glass, British Nucl Fuels plc, Pilkington plc, Soc Glass Technol HO UNIV WALES ID A-SI-H; FLUCTUATION MICROSCOPY; DISORDERED MATERIALS AB Using fluctuation electron microscopy, we have measured the medium-range order of magnetron sputtered silicon thin films as a function of substrate temperature from the amorphous to polycrystalline regimes. We find a smooth increase in the medium-range order of the samples, which we interpret in the context of the paracrystalline structural model as an increase in the size of and/or volume fraction occupied by the paracrystalline grains. These data are counter to the long-standing belief that there is a sharp transition between amorphous and polycrystalline structures as a function of substrate temperature. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. NEC Res Inst, Princeton, NJ 08540 USA. Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Univ Illinois, Coordinated Sci Lab, Urbana, IL 61801 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Voyles, PM (reprint author), Bell Labs, Lucent Technol, 700 Mt Ave,Rm 1D-437, Murray Hill, NJ 07974 USA. RI Gibson, Murray/E-5855-2013; OI Gibson, Murray/0000-0002-0807-6224; Voyles, Paul/0000-0001-9438-4284 NR 15 TC 24 Z9 24 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 293 BP 45 EP 52 DI 10.1016/S0022-3093(01)00652-4 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489CL UT WOS:000171974400008 ER PT J AU Holland, D Smith, ME Poplett, IJF Johnson, JA Thomas, MF Bland, J AF Holland, D Smith, ME Poplett, IJF Johnson, JA Thomas, MF Bland, J TI Tin germanate glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 8th International Conference on the Structure on Non-Crystalline Materials (NCM 8) CY AUG 06-11, 2000 CL UNIV WALES, ABERYSTWYTH, WALES SP Corning Glass, British Nucl Fuels plc, Pilkington plc, Soc Glass Technol HO UNIV WALES ID BOND-ANGLE DISTRIBUTION; GEO2 GLASS; NEUTRON AB Glasses of composition xSnO(1 - x)GeO2 have been prepared with 0.3 less than or equal to x less than or equal to 0.6. Crystallisation occurred for x greater than or equal to 0.7. Mossbauer and NMR spectra indicate that the Sn(Il) environment is at least as asymmetric as that found in crystalline SnO and stannosilicate glasses. Mossbauer isomer shifts are larger and quadrupolar splittings smaller than for the corresponding silicates, reflecting increased s-electron density at the nucleus with the lower covalency in the Sn-O-Ge link. Neutron diffraction data show a peak at similar to2.12 Angstrom, assigned to 3-coordinated Sn(II) and a second peak at similar to2.35 Angstrom, assigned to 6-coordinated Sn(II). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. Univ Liverpool, Dept Phys, Liverpool L69 3BX, Merseyside, England. RP Holland, D (reprint author), Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. RI Johnson, Jacqueliine/G-7365-2011; Johnson, Jacqueline/P-4844-2014 OI Johnson, Jacqueline/0000-0003-0830-9275 NR 17 TC 11 Z9 11 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 293 BP 175 EP 181 DI 10.1016/S0022-3093(01)00668-8 PG 7 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489CL UT WOS:000171974400025 ER PT J AU Bychkov, E Price, DL Lapp, A AF Bychkov, E Price, DL Lapp, A TI Universal trend of the Haven ratio in glasses: origin and structural evidences from neutron diffraction and small-angle neutron scattering SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 8th International Conference on the Structure on Non-Crystalline Materials (NCM 8) CY AUG 06-11, 2000 CL UNIV WALES, ABERYSTWYTH, WALES SP Corning Glass, British Nucl Fuels plc, Pilkington plc, Soc Glass Technol HO UNIV WALES ID X-RAY-SCATTERING; ELECTRICAL-CONDUCTIVITY; CHALCOGENIDE GLASSES; TRACER DIFFUSION; RANGE ORDER; SE AB The Haven ratio H-R exhibits a universal trend in oxide and chalcogenide glassy systems as a function of the mobile ion content x. The ion transport in extremely dilute glasses (x = 30-100 ppm M-1) is uncorrelated (H-R approximate to1), but H-R decreases rapidly with increasing x and remains nearly constant (H-R = 0.2-0.4) at x greater than or equal to 10 at.%. An experimentally verified interpretation of this phenomenon is lacking. Our neutron diffraction (ND) and small-angle neutron scattering experiments carried out over a Q-range of four orders of magnitude, from 3 x 10(3) to 40 Angstrom (-1), for a number of silver chalcogenide glassy systems suggest a structural origin for this universal trend. Glasses from the critical percolation domain (x(c) less than or equal to x less than or equal to 1-3 at.%Ag, where x(e) approximate to 30 ppm Ag is the percolation threshold) are characterised by a random silver distribution. The average Ag-Ag separation distance decreases with increasing x in this domain, leading to an increase in the interionic interactions and thus to a monotonic decrease of H-R. In contrast, glasses from the modifier-controlled domain (x greater than or equal to 10 at./ Ag) are characterised by a non-random Ag distribution. Edge-shared AgX3 pyramids (X = S, Se) form chains, cross-linking chains, sheets, tunnels, etc., depending on the system. and provide preferential conduction pathways. The interionic interactions, however, are controlled by an invariant Ag-Ag second neighbour distance of approximate to3 Angstrom, and so the Haven ratio remains essentially constant. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Littoral, UMR 8101 CNRS, LPCA, F-59140 Dunkerque, France. Argonne Natl Lab, Argonne, IL 60439 USA. Lab L Brillouin Spectrometrie Neutr, F-91911 Gif Sur Yvette, France. RP Bychkov, E (reprint author), Univ Littoral, UMR 8101 CNRS, LPCA, 145 Ave Marice Schumann, F-59140 Dunkerque, France. RI Price, David Long/A-8468-2013 NR 37 TC 33 Z9 33 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 293 BP 211 EP 219 DI 10.1016/S0022-3093(01)00673-1 PG 9 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489CL UT WOS:000171974400031 ER PT J AU Li, H Su, Y Sundaram, SK AF Li, H Su, Y Sundaram, SK TI Raman spectroscopic study of Nd-doped 10Na(2)O-90TeO(2) glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 8th International Conference on the Structure on Non-Crystalline Materials (NCM 8) CY AUG 06-11, 2000 CL UNIV WALES, ABERYSTWYTH, WALES SP Corning Glass, British Nucl Fuels plc, Pilkington plc, Soc Glass Technol HO UNIV WALES ID M = LI; TELLURITE GLASSES; SPECTRA; NA; RB; CS AB Over the Nd2O3 concentration region from 0.1 to 2.5 mol%, our Raman spectroscopic study showed that adding Nd to a base 10Na(2)O-90TeO(2), tellurite glass converts TeO4 trigonal bipyramid (tbp) units to TeO3 trigonal pyramid (tp) units and possibly some terminal TeO3+1 polyhedra. The Nd effect on the speciation of tellurite structural groups is similar to that of other monovalent (such as alkalis), divalent (such as Zn), and trivalent (such as La) metal cations. The previously observed Nd-O local structural transition was also found in the current study. Namely. a transition near 1 mol% Nd2O3 was observed in the correlations, both band position and intensity, between two Raman stretching vibration bands near 600 and 730 cm (1). The former represents the stretching vibration mode of TeO4 tbp units and the latter represents the stretching vibration mode of TeO3 tp units. A Raman band, near 465 cm(-1), represents a bending vibration mode of Te-O-Te (or O-Te-O) linkages. Our study showed a significant decrease in the E-band intensity of the glass with 2.5 mol% Nd2O3. It follows that a considerable structure disruption of the tellurite network takes place when the Nd cation is close to its solubility limit. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Environm Technol Div, Richland, WA 99352 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Li, H (reprint author), PPG Ind Inc, Glass Technol Ctr, Fiber Glass Sci & Technol, Fundamental Sci, POB 2844, Pittsburgh, PA 15230 USA. NR 13 TC 23 Z9 24 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 293 BP 402 EP 409 DI 10.1016/S0022-3093(01)00691-3 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489CL UT WOS:000171974400060 ER PT J AU Berryman, JR Feller, SA Affatigato, M Kodama, M Meyer, BM Martin, SW Borsa, F Kroeker, S AF Berryman, JR Feller, SA Affatigato, M Kodama, M Meyer, BM Martin, SW Borsa, F Kroeker, S TI Thermal, acoustic, and nuclear magnetic resonance studies of cesium borate glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 8th International Conference on the Structure on Non-Crystalline Materials (NCM 8) CY AUG 06-11, 2000 CL UNIV WALES, ABERYSTWYTH, WALES SP Corning Glass, British Nucl Fuels plc, Pilkington plc, Soc Glass Technol HO UNIV WALES ID NMR AB The purpose of this study was to compare the physical properties and structure of cesium borate glasses. Cesium borate glasses can be denoted as RCs2O . B2O3, where R is the molar ratio of cesium oxide to boron oxide. We report a detailed study of the glass transition temperature (T-g) of these cesium borate glasses with 0.0 less than or equal to R less than or equal to 0.55. Initially, the T-g increased monotonically as R rose. It then leveled out at R = 0.35 and fell at R = 0.425. The T-g data obtained using a differential scanning calorimeter (DSC) are in good agreement with Kodama et al.'s T-g results from a differential thermal analyzer (DTA) as well as Chryssikos' model of the number of bridging oxygens per boron (Z). We determined the fraction of boron atoms in tetrahedral co-ordination. N-4, for the same cesium borate glass samples using B-11 NMR. The N4 fractions followed a curve similar to that of the T-g results until R = 0.45, where it continued to rise as the T-g fell. Also. the N4 data have a similar trend but are consistently higher than those calculated from a model which employed Kodama and Kojima's ultrasonic velocity data. Finally, the NMR data do not display a significant lowering of the N-4 fraction in cesium borate when compared to lithium borate glasses. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Coe Coll, Dept Phys, Cedar Rapids, IA 52402 USA. Sojo Univ, Dept Appl Chem, Ikeda, Kumamoto 8600082, Japan. Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. Ames Natl Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. RP Feller, SA (reprint author), Coe Coll, Dept Phys, Cedar Rapids, IA 52402 USA. NR 15 TC 13 Z9 13 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 293 BP 483 EP 489 DI 10.1016/S0022-3093(01)00754-2 PG 7 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489CL UT WOS:000171974400072 ER PT J AU Petkov, V Billinge, SJL Shastri, SD Himmel, B AF Petkov, V Billinge, SJL Shastri, SD Himmel, B TI High-resolution atomic distribution functions of disordered materials by high-energy X-ray diffraction SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 8th International Conference on the Structure on Non-Crystalline Materials (NCM 8) CY AUG 06-11, 2000 CL UNIV WALES, ABERYSTWYTH, WALES SP Corning Glass, British Nucl Fuels plc, Pilkington plc, Soc Glass Technol HO UNIV WALES ID GA1-XINXAS AB The atomic-scale structure of materials with different degrees of structural disorder has been investigated by high-energy (E greater than or equal to 60 keV) X-ray diffraction. Good quality structure functions extended to wave vectors of magnitude Q greater than or equal to 40 Angstrom (-1) have been obtained even in case of materials composed of weakly scattering, light atomic species. The corresponding high-resolution atomic distribution functions allowed fine structural features differing in as little as (0.14 Angstrom) to be resolved. In particular, the distinct Ga-As (similar to2.43 Angstrom) and In-As (2.61 Angstrom) bonds in In-Ga-As alloys have been differentiated. The atomic-scale structure or 'restacked' WS2 has been determined and the presence of three distinct W-W distances occurring at 2.77, 3.27 and 3.85 Angstrom established. Finally, Si-O (similar to1.61 Angstrom), Al-O (similar to1.75 Angstrom) and Ca-O (similar to2.34 Angstrom) bonds in calcium aluminosilicate glasses have been differentiated and the characteristics of the respective co-ordination polyhedra revealed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Michigan State Univ, Ctr Fundamental Mat Res, Dept Phys & Astron, E Lansing, MI 48823 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ Rostock, FB Elektrotechn & Informat Techn, Rostock, Germany. RP Petkov, V (reprint author), Michigan State Univ, Ctr Fundamental Mat Res, Dept Phys & Astron, E Lansing, MI 48823 USA. NR 11 TC 24 Z9 24 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 293 BP 726 EP 730 DI 10.1016/S0022-3093(01)00864-X PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489CL UT WOS:000171974400111 ER PT J AU Vienna, JD Hrma, P Crum, JV Mika, M AF Vienna, JD Hrma, P Crum, JV Mika, M TI Liquidus temperature-composition model for multi-component glasses in the Fe, Cr, Ni, and Mn spinel primary phase field SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID STRUCTURAL ENVIRONMENTS; INCOMPATIBLE ELEMENTS; BOROSILICATE GLASSES; WASTE GLASSES; MELT SYSTEMS AB We developed an extensive T-L database of simulated high-level waste (HLW) glasses within the spinet primary phase field. Partial-molar T(L)s, T-j, were determined for all components that were systematically varied in database glasses (i = Al, B, Ca, Cr, Fe, K, Li, Mg, Mn, Na, Ni, Si, Ti, U, and Zr). A clear relationship was found between the T-j values and ion potential. This led to a new model that can accurately predict the T-L of glasses within component concentration ranges of the database. The model gives slightly better predictability than a first-order expansion of T-L in composition while using only half of the fitted parameters and offers an improvement in predictability over previously published models. The success of this model gives insight to the nature of component effects on T-L, which warrants further investigation. Specifically, the concentrations of glass components appear to be influential on T-L in proportion to the character of their bonds or their ionic potential. (C) 2001 Published by Elsevier Science B.V. C1 Pacific NW Natl Lab, Environm Technol Div, Richland, WA 99352 USA. RP Vienna, JD (reprint author), Pacific NW Natl Lab, Environm Technol Div, Battelle Blvd 902,POB 999,K6-24, Richland, WA 99352 USA. NR 45 TC 27 Z9 27 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 292 IS 1-3 BP 1 EP 24 DI 10.1016/S0022-3093(01)00874-2 PG 24 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489LR UT WOS:000171993300001 ER PT J AU Jiricka, A Vienna, JD Hrma, P Strachan, DM AF Jiricka, A Vienna, JD Hrma, P Strachan, DM TI The effect of experimental conditions and evaluation techniques on the alteration of low activity glasses by vapor hydration SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID FLOW-THROUGH EXPERIMENTS; SIMULATED WASTE GLASS; ALKALINE MEDIA; 40-DEGREES-C; CORROSION AB The vapor hydration test (VHT) is used to study the reaction between waste forms and water with the aim to gain insight into their alteration behavior, In nuclear-waste immobilization, the test is primarily used as a screening tool to identify durable/non-durable glasses and as a convenient method to generate and identify alteration products for use in performance modeling. The lack of a standard procedure for conducting this test has resulted in a number of reported test methods. thus decreasing the ability to directly compare test results from different sources. To optimize the VHT procedure, a series of tests was conducted on simulated low activity waste (LAW) glasses at temperatures ranging from 150 to 300 degreesC with different volumes of water, specimen holders, specimen-preparation techniques. and data-evaluation methods. Reaction progress was monitored by measuring the thickness of the remaining glass and the alteration layer, The alteration rate at which glass is converted into the alteration products was determined by linear regression from the remaining glass thickness plotted as a function of time. The resulting procedure for conducting VHT eliminates problems associated with the measurement of alteration layers and enables direct comparison of alteration rates for different materials. (C) 2001 Published by Elsevier Science B.V. C1 Pacific NW Natl Lab, Environm Technol Div, Richland, WA 99352 USA. RP Vienna, JD (reprint author), Pacific NW Natl Lab, Environm Technol Div, Battelle Blvd 902,POB 999,K6-24, Richland, WA 99352 USA. NR 25 TC 20 Z9 22 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 292 IS 1-3 BP 25 EP 43 DI 10.1016/S0022-3093(01)00875-4 PG 19 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489LR UT WOS:000171993300002 ER PT J AU Reynolds, JG Coronado, PR Hrubesh, LW AF Reynolds, JG Coronado, PR Hrubesh, LW TI Hydrophobic aerogels for oil-spill clean up - synthesis and characterization SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID SILICA AEROGELS; PHYSICAL-PROPERTIES; MIXED OXIDES; LOW-DENSITY; GEL; MIXTURES AB Hydrophobic aerogels were synthesized, characterized by IR, surface areas, relative pore size distributions and decomposition behavior, The materials were then tested for oil absorbing capacity in oil salt-water mixtures for applications to oil-spill clean up processes. Aerogels; containing the CF3(CH)(2)-group (CF3-aerogel) were successfully synthesized using (CH3O)(4)Si and nominally 30, 10, 1.5 mol% CF3(CH2)(2)Si(OCH3)(3) in CH3OH by a NH4OH catalyzed reaction followed by supercritical extraction with CH3OH. The aerogels were found to be hydrophobic based on water absorption and sessile drop experiments. By IR, the CF3(CH2)(2)-group was found to be intact after the gelation process and after supercritical drying. Si-OH-groups were also found in all cases, with decreasing amounts with increasing amounts of the CF3(CH2)(2)-group. Heating under air caused the 30% CF3-aerogel to decompose, where the transition temperature from hydrophobic to hydrophilic appeared around 375-400 degreesC, which corresponded to disappearance of the CF3(CH2)(2)-moiety bands in the IR. Treating oil and salt-water mixtures with the aerogel at an oil to aerogel ratio of 3.5 showed that all CF3-aerogels cleanly separated the oil from the water, regardless of CF3(CH)(2)-group concentration. This indicates that CF3-aerogels can absorb oil as much as 237 times their weight, much more than previously determined. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Reynolds, JG (reprint author), Lawrence Livermore Natl Lab, POB 808,L-369, Livermore, CA 94551 USA. NR 59 TC 100 Z9 106 U1 5 U2 66 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 292 IS 1-3 BP 127 EP 137 DI 10.1016/S0022-3093(01)00882-1 PG 11 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489LR UT WOS:000171993300012 ER PT J AU Li, H Su, YL Li, LY Strachan, DM AF Li, H Su, YL Li, LY Strachan, DM TI Raman spectroscopic study of gadolinium(III) in sodium-aluminoborosilicate glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; SILICATE-GLASSES; BOROSILICATE GLASSES; BORATE GLASSES; O-17 NMR; OXIDE AB A Raman spectroscopy study was performed on a series of sodium-aluminoborosilicate glasses with Gd2O3 from 0 mass% up to its solubility (47 mass% or 13.58 mol%), Experimentally measured spectra were fitted with a Gaussian function for each individual band without any restriction on the band position, width, and intensity. The evolution of the spectroscopic bands appears to result from partitioning of the rare earth cation, as its dissolution mechanism, in these borosilicate glasses. Specifically, the evolution of the Raman bands was correlated well with Gd cations partitioning in the borate-rich environment at low Gd2O3 concentration, Gd2O3/[1/3B(2)O(3)] < 1, and excess Gd cations, Gd2O3-1/3B(2)O(3), in the silicate-rich environment at high Gd2O3 concentration, Gd2O3/[1/3B(2)O(3)] > 1. Raman bands near 1420 and 710 cm(-1) suggest the presence of a local Gd-metaborate environment, which appeared to occur at all Gd2O3 concentrations. The bands near 300 and 910 cm(-1) further suggest the formation of Gd-O-Gd clusters in the silicate-rich environment at high Gd2O3 concentrations. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Li, H (reprint author), PPG Ind Inc, Glass Technol Ctr, Fundamental Sci, Fiber Glass Sci & Technol, POB 2844, Pittsburgh, PA 15230 USA. NR 36 TC 45 Z9 47 U1 1 U2 21 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD NOV PY 2001 VL 292 IS 1-3 BP 167 EP 176 DI 10.1016/S0022-3093(01)00878-X PG 10 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 489LR UT WOS:000171993300016 ER PT J AU Spearing, DR Veirs, DK Prenger, FC AF Spearing, DR Veirs, DK Prenger, FC TI Effect of the expansion associated with the plutonium alpha-beta-gamma phase transitions on storage can integrity SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article AB The effects of the volume expansion of plutonium metal through the alpha-beta and beta-gamma phase transitions on a stainless steel storage container were examined. A cylindrical plutonium ingot was placed in the axial center of an annealed stainless steel cylinder and thermally cycled until a steady state in the strain response of the cylinder was reached. The average plastic hoop strain was 1.47% and 1.55% after six and four cycles through the alpha-beta and alpha-beta-gamma phase transitions, respectively. Elastic strain was similar to0.2%, indicating a 8.96 MPa back pressure on the Pu ingot. This is an order of magnitude less than the compressive yield strength of alpha- and beta -Pu at the transition temperature. Metallographic analyses indicate that anisotropic expansion of the Pu ingot is due to preferentially oriented grain growth of the beta -Pu along the axial direction due to stress applied by the steel cylinder during the alpha-beta phase transition. Published by Elsevier Science B.V. C1 Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Engn Sci & Applicat Div, Los Alamos, NM 87545 USA. RP Spearing, DR (reprint author), Los Alamos Natl Lab, Div Nucl Mat Technol, MS E505, Los Alamos, NM 87545 USA. NR 21 TC 5 Z9 5 U1 3 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD NOV PY 2001 VL 299 IS 2 BP 111 EP 123 DI 10.1016/S0022-3115(01)00683-3 PG 13 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 488JQ UT WOS:000171932400003 ER PT J AU Williford, RE Weber, WJ AF Williford, RE Weber, WJ TI Computer simulation of Pu3+ and Pu4+ substitutions in gadolinium zirconate SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID OXYGEN VACANCY MIGRATION; SELF-RADIATION DAMAGE; GD2TI2O7; STABILITY; SYSTEM AB Atomistic computer simulations have been used to determine the energetics of a variety of defect reactions related to the incorporation of Pu3+ and Pu4+ into the pyrochlore and the fluorite-type structures of Gd2Zr2O7. The lowest energy states were found for Pu3+ substitutions on Gd sites in the pyrochlore (- 1.00 eV/Pu) and the fluorite-type (- 1.55 eV/Pu) structures, so these defect reactions are the most likely configurations under reducing conditions that favor Pu3+ ions. Slightly higher, but still exothermic, energies (-0.26 to -0.45 ev) were calculated for Pu4+ substitutions on Zr sites for several fluorite-type cases, indicating that oxidizing conditions should favor Pu4+ incorporation on Zr sites in Gd2Zr2O7 hosts. Defect reactions involving cation vacancies or interstitials exhibited significantly higher energies, and are therefore not expected to occur. Mean field calculations indicated that the increases in crystal Volume associated with Pu incorporation are minimized by the excess free volume associated with the Gd site in the pyrochlore structure. Volume changes upon thermal phase transformation from fluorite to pyrochlore are smaller for the material incorporating Pu by substitution than for the virgin material, with a slight advantage for the reducing conditions associated with Pu3+ substitutions on Gd sites. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Mat Dept, Richland, WA 99352 USA. RP Williford, RE (reprint author), Pacific NW Natl Lab, Mat Dept, MS K2-44,POB 999, Richland, WA 99352 USA. RI Weber, William/A-4177-2008 OI Weber, William/0000-0002-9017-7365 NR 24 TC 21 Z9 23 U1 4 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD NOV PY 2001 VL 299 IS 2 BP 140 EP 147 DI 10.1016/S0022-3115(01)00687-0 PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 488JQ UT WOS:000171932400006 ER PT J AU Muroga, T Zinkle, SJ Qualls, AL Watanabe, H AF Muroga, T Zinkle, SJ Qualls, AL Watanabe, H TI Varying temperature irradiation experiment in HFIR SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID FISSION REACTOR IRRADIATION; NEUTRON-IRRADIATION; HISTORY AB Post-irradiation examination has started and initial results are available for the varying temperature irradiation experiment conducted in the high flux isotope reactor (HFIR), carried out in the framework of the Japan-USA Fusion Cooperation Program (JUPITER project). This experiment is an unprecedented controlled irradiation experiment designed for symmetrical comparison of isothermal and temperature-variant neutron irradiation effects. This paper summarizes the irradiation experiments and initial results obtained from the post-irradiation examination of an austenitic alloy, vanadium, a vanadium alloy and copper. These preliminary results extend the trends observed in earlier, lower fluence experiments, with some effects of the low temperature phase of variable temperature irradiation on evolving microstructures. (C) 2001 Elsevier Science B.V. AU rights reserved. C1 Natl Inst Fus Sci, Gifu 5095292, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Kyushu Univ, Appl Mech Res Inst, Kasuga, Fukuoka 8168580, Japan. RP Muroga, T (reprint author), Natl Inst Fus Sci, 322-6 Oroshi, Gifu 5095292, Japan. RI U-ID, Kyushu/C-5291-2016; Kyushu, RIAM/F-4018-2015; OI Zinkle, Steven/0000-0003-2890-6915 NR 43 TC 13 Z9 14 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD NOV PY 2001 VL 299 IS 2 BP 148 EP 156 DI 10.1016/S0022-3115(01)00675-4 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 488JQ UT WOS:000171932400007 ER PT J AU Gan, YX Aglan, HA Steward, RV Chin, BA Grossbeck, ML AF Gan, YX Aglan, HA Steward, RV Chin, BA Grossbeck, ML TI Microstructure-fracture toughness relationship of vanadium alloy/stainless steel brazed joints SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID AMORPHOUS FILLER METALS; Q-AND-A; BRAZING CHARACTERISTICS; THERMAL-STABILITY; ALLOYS; BERYLLIUM; TEXTOR; TI AB In this work, brazing V-5Ti-5Cr to 304 stainless steel (SS 304) using Au-18Ni alloy as filler material was conducted under high vacuum condition. Sessile drop technique was used to determine the wettability of filler alloy to the stainless steel and the vanadium alloy substrates upon which the relationship between the contact angles with time was obtained. Tensile tests were performed on unnotched and notched specimens to demonstrate the overloading behavior and the fracture toughness of the base materials and the brazed joint. Fracture surface was examined for both the V-5Ti-5Cr and the joint to identify the failure mechanisms under static loadings. It was found that the Au-18Ni filler material exhibited good wettability with the SS 304 and V-5Ti-5Cr. The ultimate tensile strength of the brazed joint reached 245 MPa. The strain to failure was about 1.3%. Young's modulus was about 351 GPa. The fracture toughness (K,,) of this joint was 19.1 MPa rootm. The fracture surface of the joint showed well brazed area with good wettability and proper amount of residual filler material which came from the solidification of residual liquid filler alloy of Au-Ni. The failure of the joint occurred along the interface of the vanadium/filler under static load. (C) 2001 Published by Elsevier Science B.V. C1 Tuskegee Univ, Dept Mech Engn, Tuskegee, AL 36088 USA. Auburn Univ, Mat Engn Program, Auburn, AL 36849 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Aglan, HA (reprint author), Tuskegee Univ, Dept Mech Engn, Tuskegee, AL 36088 USA. NR 60 TC 12 Z9 16 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD NOV PY 2001 VL 299 IS 2 BP 157 EP 164 DI 10.1016/S0022-3115(01)00677-8 PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 488JQ UT WOS:000171932400008 ER PT J AU Meyer, MK Hofman, GL Wiencek, TC Hayes, SL Snelgrove, JL AF Meyer, MK Hofman, GL Wiencek, TC Hayes, SL Snelgrove, JL TI Irradiation behavior of U-Nb-Zr alloy dispersed in aluminum SO JOURNAL OF NUCLEAR MATERIALS LA English DT Letter AB Three U-Nb-Zr alloys (U-5Nb-3Zr, U-6Nb-4Zr, and U-9Nb-3Zr) were included in a screening irradiation test of low-enrichment aluminum matrix dispersion fuels. Fuel particles made from these alloys reacted readily with aluminum during fuel fabrication and post-fabrication annealing, resulting in large fuel plate thickness increases. Under irradiation, the behavior of U-5N-b-3Zr (wt%) alloy based fuel was poor at 41 at.% U-235 burnup, showing indications of incipient breakaway swelling. The post-irradiation microstructural characteristics of U-6Nb-4Zr based fuel were somewhat better than those of U-5Nb-3Zr, but is marginal at 70 at.% burnup. U-Mo based fuels generally show less reaction on fabrication and better fuel performance characteristics during irradiation. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab W, Idaho Falls, ID 83403 USA. Argonne Natl Lab E, Argonne, IL 60439 USA. RP Meyer, MK (reprint author), Argonne Natl Lab W, POB 2528, Idaho Falls, ID 83403 USA. RI Hayes, Steven/D-8373-2017; OI Hayes, Steven/0000-0002-7583-2069; Meyer, Mitchell/0000-0002-1980-7862 NR 14 TC 17 Z9 17 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD NOV PY 2001 VL 299 IS 2 BP 175 EP 179 DI 10.1016/S0022-3115(01)00676-6 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 488JQ UT WOS:000171932400011 ER PT J AU Sitek, A Gullberg, GT Di Bella, EVR Celler, A AF Sitek, A Gullberg, GT Di Bella, EVR Celler, A TI Reconstruction of dynamic renal tomographic data acquired by slow rotation SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article DE dynamic SPECT; factor analysis; tomographic renal studies ID KINETIC PARAMETER-ESTIMATION; MODEL-BASED ESTIMATION; PROJECTION MEASUREMENTS; PRINCIPAL-COMPONENTS; EMISSION-TOMOGRAPHY; SPECT; ALGORITHM; SEQUENCES; PHANTOM AB Nuclear medicine renal studies can be performed using slow-rotation SPECT, but reconstruction of such data is largely underdetermined. Methods: A new method of reconstruction of data acquired using slow camera rotations was developed. In this method we used a factor model of the data in which the factors and factor coefficients were determined by modeling their relationship directly with the projection measurements. This was done by solving a least-squares problem that fits the projections of factors and factor coefficients to the projection data with nonnegativity constraints imposed on the solution. The method was tested on computer simulations and applied to experimental renal Tc-99m-mercaptoacetyltriglycine canine and patient studies. Results: Computer simulations showed that the extracted time-activity curves of kidneys agreed well with the simulated curves for data with noise levels similar to those in the experimental studies. In the canine study, the method showed that >2 factors were necessary to adequately reproduce the kinetics of the kidney. In the patient study, the method was able to extract separate factors that correspond to the kidney cortex and the kidney pelvis. Conclusion: The computer simulation, the canine study, and the patient study all show that reconstructions of the data obtained with 1 detector displayed artifacts, whereas reconstructions of the data obtained with 2 and 3 detectors were free of artifacts. Computer simulations showed that the method gives accurate results that allow quantitation. C1 Vancouver Hosp & Hlth Sci Ctr, Vancouver, BC V5Z 1M9, Canada. Univ Utah, Dept Radiol, Salt Lake City, UT 84132 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Sitek, A (reprint author), Beth Israel Deaconess Med Ctr, Dept Radiol, 330 Brookline Ave, Boston, MA 02215 USA. OI DiBella, Edward/0000-0001-9196-3731; Sitek, Arkadiusz/0000-0002-0677-4002 FU NHLBI NIH HHS [HL 50663] NR 28 TC 18 Z9 18 U1 0 U2 2 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD NOV PY 2001 VL 42 IS 11 BP 1704 EP 1712 PG 9 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 491CR UT WOS:000172090900029 PM 11696643 ER PT J AU Gaiser, EE Taylor, BE Brooks, MJ AF Gaiser, EE Taylor, BE Brooks, MJ TI Establishment of wetlands on the southeastern Atlantic Coastal Plain: Paleolimnological evidence of a mid-Holocene hydrologic threshold from a South Carolina pond SO JOURNAL OF PALEOLIMNOLOGY LA English DT Article DE diatoms; Carolina bays; paleolimnology; wetlands; South Carolina; Atlantic Coastal Plain; hydrology; Holocene ID DIATOMS; VEGETATION; GEORGIA; BAYS AB The series of climatic events affecting landscapes on the southeastern Atlantic Coastal Plain over the past several thousand years is poorly understood. This is due, in part, to the paucity of depositional basins in this region containing adequately preserved microfossils for paleoecological analyses. This research reconstructs past hydrologic environments from the microfossil record of Peat Bay, a small, peat-filled pond in south-central South Carolina. We cored the deepest location in the pond and retrieved 120 cm of sediment representing 5200 yr of deposition. Fine clays at the base of the core resembled sediments deposited in abandoned channels of the nearby Savannah River, suggesting the basin may have functioned as an oxbow wetland prone to periodic flooding and drying. Overlying peats containing planktonic diatom assemblages mark the onset of persistent open-water conditions ca. 4600 B.P. These data, in conjunction with a small body of paleoecological evidence from other southeastern wetlands, suggest that a hydrologic 'threshold' was surpassed during the mid-Holocene that resulted in flooding and expansion of low-lying depressions that characterize the regional landscape. This is likely the culmination of long-term hydrologic trends related to glacial retreat, including increased precipitation and a rise in ground water levels corresponding to a global rise in sea level. In Peat Bay, lake-like conditions persisted until about 3800 B.P., after which time aerophilic diatoms and remains of other temporary pond organisms dominated the fossil record. Episodic drying of pond sediments during the late-Holocene may have been a response to decreased precipitation, stabilization of the water table and infilling of the pond by decaying vegetation and terrigenous clastics. The microfossil record indicates that temporary pond conditions persisted until recent years (ca. 1985) when the basin returned to a permanently flooded state due to groundwater connection to a large reservoir constructed nearby. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Univ S Carolina, S Carolina Inst Archaeol & Anthropol, Savannah River Archaeol Res Program, New Ellenton, SC 29809 USA. RP Gaiser, EE (reprint author), Florida Int Univ, SE Environm Res Ctr, Miami, FL 33199 USA. NR 56 TC 12 Z9 12 U1 1 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0921-2728 J9 J PALEOLIMNOL JI J. Paleolimn. PD NOV PY 2001 VL 26 IS 4 BP 373 EP 391 DI 10.1023/A:1012645302945 PG 19 WC Environmental Sciences; Geosciences, Multidisciplinary; Limnology SC Environmental Sciences & Ecology; Geology; Marine & Freshwater Biology GA 490UW UT WOS:000172071900002 ER PT J AU Brightwell, R Plimpton, S AF Brightwell, R Plimpton, S TI Scalability and performance of two large Linux clusters SO JOURNAL OF PARALLEL AND DISTRIBUTED COMPUTING LA English DT Article DE massively parallel; workstation cluster; message passing ID PARALLEL AB In this paper, we present performance results from several parallel benchmarks and applications on two large Linux clusters at Sandia National Laboratories. We compare the results on the Linux clusters to performance obtained on a traditional distributed-memory massively parallel processing machine, the Intel TeraFLOPS. We discuss the characteristics of these machines that influence the performance results and identify the key components of the system that are important to allow for scalability of commodity-based PC clusters to hundreds and possibly thousands of processors. (C) 2001 Academic Press. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Brightwell, R (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 24 TC 9 Z9 9 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0743-7315 J9 J PARALLEL DISTR COM JI J. Parallel Distrib. Comput. PD NOV PY 2001 VL 61 IS 11 BP 1546 EP 1569 DI 10.1006/jpdc.2001.1756 PG 24 WC Computer Science, Theory & Methods SC Computer Science GA 497JY UT WOS:000172452900003 ER PT J AU Pawar, RJ Edwards, EB Whitney, EM AF Pawar, RJ Edwards, EB Whitney, EM TI Geostatistical characterization of the Carpinteria Field, California SO JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING LA English DT Article DE geostatistics; uncertainty analysis; Carpinteria Field; reservoir characterization AB This paper describes application of geostatistical techniques for detailed characterization of a geologically complex oil reservoir. The reservoir is mature and the characterization is aimed at facilitating its further development. A geological structure and stratigraphy model of the field has already been developed. Stochastic distributions of important reservoir rock properties were subsequently generated. Different techniques were applied to generate these distributions. A variety of data sources were integrated for each property. Multiple realizations were combined to assess uncertainty in property distributions. These measures of uncertainty and the detailed property realizations will be helpful for the field operator for assessing future field development scenarios. Published by Elsevier Science B.V. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Pacific Operators Offshore Inc, Santa Barbara, CA USA. RP Pawar, RJ (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 1 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-4105 J9 J PETROL SCI ENG JI J. Pet. Sci. Eng. PD NOV PY 2001 VL 31 IS 2-4 BP 175 EP 192 DI 10.1016/S0920-4105(01)00129-2 PG 18 WC Energy & Fuels; Engineering, Petroleum SC Energy & Fuels; Engineering GA 500RJ UT WOS:000172640300009 ER PT J AU Fontenot, CJ Wiench, JW Pruski, M Schrader, GL AF Fontenot, CJ Wiench, JW Pruski, M Schrader, GL TI Vanadia gel synthesis via peroxovanadate precursors. 2. Characterization of the gels SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MAGNETIC-RESONANCE SPECTRA; PENTOXIDE GELS; AMORPHOUS V2O5; V-51 NMR; OXIDE; QUADRUPOLE; SOLIDS AB Vanadium oxide gels derived from the reaction of H2O2 and V2O5 have been investigated using V-51 MAS NMR, TGA, XRD, SEM, and laser Raman spectroscopy. Based primarily on the V-51 MAS NMR and TGA results, the coordinations of five distinct vanadia sites have been detailed, which possibly include a previously unreported dimer. The relative concentration of these sites changed as dehydration progressed, and a model of this process has been proposed based on the numerical analysis of the NMR MAS spectra. In addition, the coordination of the most tightly bound water has been postulated. Depending on sample treatment, it was possible to synthesize both layered and nonlayered materials. The laser Raman spectra revealed differences between layered and nonlayered materials. These differences have been attributed to the interaction of coordinated water molecules, which were trapped between layers and held firmly in place, thus restricting or altering certain Raman-active vibrations. C1 Iowa State Univ Sci & Technol, Dept Chem Engn, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, USDOE, Ames, IA 50011 USA. RP Schrader, GL (reprint author), Iowa State Univ Sci & Technol, Dept Chem Engn, Ames, IA 50011 USA. NR 25 TC 27 Z9 27 U1 2 U2 22 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 NOV 1 PY 2001 VL 105 IS 43 BP 10496 EP 10504 DI 10.1021/jp010351f PG 9 WC Chemistry, Physical SC Chemistry GA 489YH UT WOS:000172020200009 ER PT J AU Giraudeau, A Lobstein, S Ruhlmann, L Melamed, D Barkigia, KM Fajer, J AF Giraudeau, A Lobstein, S Ruhlmann, L Melamed, D Barkigia, KM Fajer, J TI Electrosynthesis, electrochemistry, and crystal structure of the tetracationic Zn-meso-tetrapyridiniumyl-beta-octaethylporphyrin SO JOURNAL OF PORPHYRINS AND PHTHALOCYANINES LA English DT Article DE electrosynthesis; tetracationic tetra(N-pyridiniumyl) porphyrin; redox chemistry; crystallography; molecular structure; saddle conformation ID NONPLANAR PORPHYRINS; TETRAPHENYLPORPHYRIN; OXIDATION; METALLOPORPHYRINS; DIMERS; ARRAYS; ZINC AB Exhaustive electro-oxidation of ZnOEP in the presence of pyridine and Et4NPF6 affords in high yield the new tetracationic porphyrin in which the four meso protons of ZnOEP are replaced by four pyridinium groups linked via their nitrogens: [Zn-5,10,15,20-tetrakis(N-pyridiniumyl)-2,3,7,8,12,13,17,18-octaethylporphytin](4+) (PF6-)(4), I. The compound has been characterized by elemental analysis, H-1 NMR, and crystallography. The latter confirms the preparative electrosynthetic methodology and molecular structure of 1, and shows the porphyrin skeleton to adopt a severely nonplanar saddle conformation which minimizes steric crowding between the 12 peripheral substituents. As a consequence of the nonplanarity (and the high charge) of the complex, I exhibits significant redshifts of the visible and Soret bands as well as a considerable broadening and loss of intensity of the latter. I first undergoes four one-electron reduction steps at the four pyridinium sites before the normal one-electron reduction of the porphyrin pi -system. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Brookhaven Natl Lab, Energy Sci & Technol Dept, Upton, NY 11973 USA. Univ Strasbourg 1, CNRS, UMR 7512, Lab Electrochim & Chim Phys Corps Solide, F-67000 Strasbourg, France. Univ Paris 11, CNRS, UMR 8000,Grp TEMiC, Lab Chim Phys,Equipe Electrochim & Photoelectroch, F-91405 Orsay, France. RP Fajer, J (reprint author), Brookhaven Natl Lab, Energy Sci & Technol Dept, Bldg 555, Upton, NY 11973 USA. NR 35 TC 22 Z9 22 U1 0 U2 2 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1088-4246 J9 J PORPHYR PHTHALOCYA JI J. Porphyr. Phthalocyanines PD NOV PY 2001 VL 5 IS 11 BP 793 EP 797 DI 10.1002/jpp.547 PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA 486PF UT WOS:000171825600004 ER PT J AU Chen, SS Srikantiah, GS AF Chen, SS Srikantiah, GS TI Motion-dependent fluid force coefficients for tube arrays in crossflow SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID FLOW; VIBRATION AB Fluidelastic instability of tube arrays in crossflow is interesting academically and important in steam generators and heat exchangers. The key elements necessary to accurately predict fluidelastic instability of tube arrays in crossflow are motion-dependent fluid force coefficients. This paper presents several series of experiments that measure motion-dependent fluid forces for various tube arrays. Fluid damping and stiffness coefficients based on the unsteady flow theory were obtained as a function of reduced flow velocity, excitation amplitude, and Reynolds number, and the characteristics of motion-dependent fluid force coefficients were applied to provide some additional insights into fluidelastic instability. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Elect Power Res Inst, Palo Alto, CA 94303 USA. RP Chen, SS (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 29 TC 7 Z9 10 U1 1 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD NOV PY 2001 VL 123 IS 4 BP 429 EP 436 DI 10.1115/1.1401022 PG 8 WC Engineering, Mechanical SC Engineering GA 501EE UT WOS:000172669200006 ER PT J AU Hsu, CW DiPrete, AP Eibling, RE AF Hsu, CW DiPrete, AP Eibling, RE TI Organic analyses of highly radioactive solutions requiring pretreatment by Cs-137 removal SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article AB The beta-emitting radionuclide Cs-137 is precipitated from the Savannah River Site (SRS) high-level waste by adding sodium tetraphenylborate (TPB). The concentrated and washed precipitate slurry containing CsTPB is transferred to Defense Waste Processing Facility (DWPF) Salt Processing Cell and hydrolyzed to yield an aqueous product (PHA) free of benzene. The PHA is highly radioactive (1E+11 dpm) and contains some water-soluble organic compounds that need to be analyzed for process control and process history. High performance liquid chromatography (HPLC) methods were developed to analyze these compounds with instruments contained in unshielded fume hoods. Removing 137CS from pHA in a shielded cell prior to HPLC analyses is essential to minimize personnel radiation exposure. In this study ammonium molybdophosphate (Bio-Rad AMP-1) was used for removing Cs-137 in PHA (PH 3.8). With a two-step application of AMP slurry, a decontamination factor of 1E+4 was achieved for Cs removal. Two separate HPLC methods were used to analyze four polar organic compounds. The recovery of all the organic compounds were above 85%. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Hsu, CW (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. NR 6 TC 4 Z9 5 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD NOV PY 2001 VL 250 IS 2 BP 223 EP 229 DI 10.1023/A:1017996718061 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 494FJ UT WOS:000172270800001 ER PT J AU Campbell, JA Hess, WP Lohman, JR Goheen, SC AF Campbell, JA Hess, WP Lohman, JR Goheen, SC TI Analysis of Hanford-related organics using matrix-assisted laser desorption ionization time-of-flight mass spectrometry SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article ID MIXED HAZARDOUS WASTES; NITRILOTRIACETIC ACID AB Matrix-assisted laser desorption/ionization coupled with time-of-flight mass spectrometry (MALDI/TOF-MS) was used for the analysis of low-molecular phosphate compounds found in Hanford tank wastes. The mass spectra of these compounds indicate protonated peaks as well as sodium adducts. Analytical methods presently utilized for the analysis of the phosphate-related organics are both time consuming and labor intensive. A promising alternative is MALDI/TOFMS. The MALDI process produces both positive and negative ions directly and very little sample is required. In addition, there is limited sample preparation and minimal hazardous waste production. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Campbell, JA (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Lohman, Jeremy/M-1111-2015 OI Lohman, Jeremy/0000-0001-8199-2344 NR 25 TC 2 Z9 2 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD NOV PY 2001 VL 250 IS 2 BP 247 EP 253 DI 10.1023/A:1017954420787 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 494FJ UT WOS:000172270800004 ER PT J AU Schroeder, NC Radzinski, SD Ashley, KR Truong, AP Whitener, GD AF Schroeder, NC Radzinski, SD Ashley, KR Truong, AP Whitener, GD TI Feed adjustment chemistry for Hanford 101-SY and 103-SY tank waste: Attempts to oxidize the non-pertechnetate species SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article ID X-RAY STRUCTURE; COMPLEX; TC-99 AB More than 50% of the technetium in Hanford 101-SY and 103-SY tank waste is not pertechnetate (TcO4-). These non-pertechnetate species (TcN) are stable, soluble, reduced complexes of technetium. In order to remediate these waste, it will be necessary to oxidize these species to TcO4- For radioanalytical purposes, oxidation requires digestion in Ce(IV)/16M HNO3. Many oxidants are ineffective. Sodium peroxydisulfate, sodium peroxydisulfate/silver(I), and ozone oxidize all of the technetium species to pertechnetate. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Texas A&M Univ, Dept Chem, Commerce, TX 75429 USA. Macalester Coll, Dept Chem, Minneapolis, MN 55105 USA. RP Schroeder, NC (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 26 TC 10 Z9 10 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD NOV PY 2001 VL 250 IS 2 BP 271 EP 284 DI 10.1023/A:1017927109400 PG 14 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 494FJ UT WOS:000172270800008 ER PT J AU Wong-Ng, W Siegrist, T De Titta, GT Finger, LW Evans, HT Gabe, EJ Enright, GD Armstrong, JT Levenson, M Cook, LP Hubbard, CR AF Wong-Ng, W Siegrist, T De Titta, GT Finger, LW Evans, HT Gabe, EJ Enright, GD Armstrong, JT Levenson, M Cook, LP Hubbard, CR TI Standard Reference Material (SRM 1990) for single crystal diffractometer alignment SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE alignment standard; Cr-content; international round robin; NIST SRM 1990; ruby spheres; single crystal x-ray diffractometers ID CONSTANTS AB An international project was successfully completed which involved two major undertakings: (1) a round-robin to demonstrate the viability of the selected standard and ( 2) the certification of the lattice parameters of the SRM 1990, a Standard Reference Material(R) for single crystal diffractometer alignment. This SRM is a set of approximate to 3500 units of Cr-doped Al2O3, or ruby spheres [ (0.420.011 mole fraction % C ( expanded uncertainty)]. The round-robin consisted of determination of lattice parameters of a pair of crystals: the ruby sphere as a standard, and a zeolite reference to serve as an unknown. Fifty pairs of crystals were dispatched from Hauptman-Woodward Medical Research Institute to volunteers in x-ray laboratories world-wide. A total of 45 sets of data was received from 32 laboratories. The mean unit cell parameters of the ruby spheres was found to be a = 4.7608 Angstrom +/- 0.0062 Angstrom, and c = 12.9979 Angstrom +/- 0.020 Angstrom ( 95 % intervals of the laboratory means). The source of errors of outlier data was identified. The SRM project involved the certification of lattice parameters using four well-aligned single crystal diffractometers at ( Bell Laboratories) Lucent Technologies and at NRC of Canada ( 39 ruby spheres), the quantification of the Cr content using a combined microprobe and SEM/EDS technique, and the evaluation of the mosaicity of the ruby spheres using a double-crystal spectrometry method. A confirmation of the lattice parameters was also conducted using a Guinier-Hagg camera. Systematic corrections of thermal expansion and refraction corrections were applied. These rubies are rhombohedral, with space group R 3 c. The certified mean unit cell parameters are a = 4.76080 +/- 0.00029 Angstrom, and c = 12.99568 Angstrom +/- 0.00087 Angstrom ( expanded uncertainty). These certified lattice parameters fall well within the results of those obtained from the international round-robin study. The Guinier-Hagg transmission measurements on five samples of powdered rubies ( a = 4.7610 Angstrom +/- 0.0013 Angstrom, and c = 12.9954 Angstrom +/- 0.0034 Angstrom) agreed well with the values obtained from the single crystal spheres. C1 NIST, Mat Sci & Engn Lab, Div Ceram, Gaithersburg, MD 20899 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. Lund Univ, S-22100 Lund, Sweden. Hauptman Woodward Med Res Inst, Buffalo, NY 14203 USA. Carnegie Inst Washington, Geophys Lab, Washington, DC 20015 USA. US Geol Survey, Reston, VA 22092 USA. Natl Res Council Canada, Steacie Inst Mol Sci, Ottawa, ON K1A 0R6, Canada. NIST, Surface & Microanaly Sci Div, Chem Sci & Technol Lab, Gaithersburg, MD 20899 USA. Oak Ridge Natl Lab, Div Met & Ceram, Diffract & Thermophys Properties Grp, Oak Ridge, TN 37831 USA. RP Wong-Ng, W (reprint author), NIST, Mat Sci & Engn Lab, Div Ceram, Gaithersburg, MD 20899 USA. NR 39 TC 9 Z9 9 U1 0 U2 10 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD NOV-DEC PY 2001 VL 106 IS 6 BP 1071 EP 1095 PG 25 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 527WM UT WOS:000174211000014 PM 27500067 ER PT J AU Berg, DE AF Berg, DE TI A message from the special issue editor SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Editorial Material C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Berg, DE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 265 EP 266 DI 10.1115/1.1408308 PG 2 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900001 ER PT J AU Fingersh, LJ AF Fingersh, LJ TI Unsteady aerodynamics experiment SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article C1 NREL, Golden, CO 80401 USA. RP Fingersh, LJ (reprint author), NREL, 1617 Cole Blvd,MS 3811, Golden, CO 80401 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 267 EP 267 DI 10.1115/1.1374208 PG 1 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900002 ER PT J AU O'Dell, K AF O'Dell, K TI Improved blade designs and manufacturing processes reduce the cost of wind energy SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article C1 Natl Renewable Energy Lab, Natl Wind Technol Ctr, Golden, CO 80401 USA. RP O'Dell, K (reprint author), Natl Renewable Energy Lab, Natl Wind Technol Ctr, 1617 Cole Blvd, Golden, CO 80401 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 268 EP 268 DI 10.1115/1.1409558 PG 1 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900003 ER PT J AU O'Dell, K AF O'Dell, K TI NREL's dynamometer helps industry engineers test full-scale wind turbines SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article C1 Natl Renewable Energy Lab, Natl Wind Technol Ctr, Golden, CO 80401 USA. RP O'Dell, K (reprint author), Natl Renewable Energy Lab, Natl Wind Technol Ctr, 1617 Cole Blvd, Golden, CO 80401 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 269 EP 269 DI 10.1115/1.1409557 PG 1 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900004 ER PT J AU Rumsey, MA Musial, W AF Rumsey, MA Musial, W TI Application of acoustic emission nondestructive testing during wind turbine blade tests SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article C1 Sandia Natl Labs, Wind Energy Technol Dept, Albuquerque, NM 87185 USA. Natl Renewable Energy Lab, Natl Wind Technol Ctr, Golden, CO 80401 USA. RP Rumsey, MA (reprint author), Sandia Natl Labs, Wind Energy Technol Dept, POB 5800,MS 0708, Albuquerque, NM 87185 USA. NR 0 TC 4 Z9 5 U1 0 U2 5 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 270 EP 270 DI 10.1115/1.1409559 PG 1 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900005 ER PT J AU Rumsey, MA Musial, W AF Rumsey, MA Musial, W TI Application of infrared thermography nondestructive testing during wind turbine blade tests SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article C1 Sandia Natl Labs, Wind Energy Technol Dept, Albuquerque, NM 87185 USA. Natl Renewable Energy Lab, Natl Wind Technol Ctr, Golden, CO 80401 USA. RP Rumsey, MA (reprint author), Sandia Natl Labs, Wind Energy Technol Dept, POB 5800,MS 0708, Albuquerque, NM 87185 USA. NR 0 TC 12 Z9 15 U1 0 U2 11 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 271 EP 271 DI 10.1115/1.1409560 PG 1 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900006 ER PT J AU Schreck, SJ Robinson, MC Hand, MM Simms, DA AF Schreck, SJ Robinson, MC Hand, MM Simms, DA TI Blade dynamic stall vortex kinematics for a horizontal axis wind turbine in yawed conditions SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT AIAA Aerospace Sciences Meeting and Exhibit/Wind Energy Symposium CY JAN 11-14, 2001 CL RENO, NEVADA ID UNSTEADY AB Horizontal axis wind turbines routinely suffer significant time varying aerodynamic loads that adversely impact structures, mechanical components, and power production. As lighter and more flexible wind turbines are designed to reduce overall cost of energy, greater accuracy and reliability will become even more crucial in future aerodynamics models. However, to render calculations tractable, current modeling approaches admit various approximations that can degrade model predictive accuracy. To help understand the impact of these modeling approximations and improve future models, the current effort seeks to document and comprehend the vortex kinematics for three-dimensional, unsteady, vortex dominated flows occurring on horizontal axis wind turbine blades during non-zero yaw conditions. To experimentally characterize these flows, the National Renewable Energy Laboratory Unsteady Aerodynamics Experiment turbine was erected in the NASA Ames 80 ft x 120 ft wind tunnel. When, under strictly-controlled inflow conditions, turbine blade surface pressures and local inflow velocities were acquired at multiple radial locations. Surface pressure histories and normal force records were used to characterize dynamic stall vortex kinematics and normal forces. Stall vortices occupied approximately two-thirds of the aerodynamically active blade span and persisted for nearly one-fourth of the blade rotation cycle. Stall vortex convection varied dramatically along the blade radius, yielding pronounced dynamic stall vortex deformation. Analysis of these data revealed systematic alterations to vortex kinematics due to changes in test section speed, yaw error, and blade span location. C1 Natl Renewable Energy Lab, Natl Wind Technol Ctr, Appl Res Div, Golden, CO 80401 USA. RP Schreck, SJ (reprint author), Natl Renewable Energy Lab, Natl Wind Technol Ctr, Appl Res Div, 1617 Cole Blvd, Golden, CO 80401 USA. NR 44 TC 17 Z9 17 U1 0 U2 5 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 272 EP 281 DI 10.1115/1.1408307 PG 10 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900007 ER PT J AU Nakafuji, DTY van Dam, CP Smith, RL Collins, SD AF Nakafuji, DTY van Dam, CP Smith, RL Collins, SD TI Active load control for airfoils using microtabs SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID UPWIND DIFFERENCING SCHEME; NAVIER-STOKES EQUATIONS; GURNEY FLAP; DRAG AB Micro-electro-mechanical (MEM) translational tabs are introduced for active load control on aerodynamic surfaces such cis wind turbine rotor blades. Microtabs are mounted near the trailing edge of rotor blades, deploy approximately normal to the surface, and have a maximum deployment height on the order of the boundary-layer thickness. Deployment of the tab effectively changes the sectional chamber of the rotor blade, thereby changing its aerodynamic characteristics. A tab with tab height to blade section chord ratio, h/c, of 0.01 causes an increase in the section lift coefficient, C-1, of approximately 0.3, with minimal drag penalty. This paper presents a proof of concept microtab design and the multi-disciplinary techniques used to fabricate and test the tabs. Computational and experimental wind tunnel results for a representative airfoil using fixed as well as remotely actuated tabs are compared. Although the specifics of load control limitations, including actuation and response tinies will require further research, the results presented demonstrate the significant potential for using microtabs for active load control. C1 Lawrence Livermore Natl Lab, New Technol Engn Div, Livermore, CA 94551 USA. Univ Calif Davis, Dept Mech & Aeronaut Engn, Davis, CA 95616 USA. Univ Calif Davis, Dept Elect & Comp Engn, Davis, CA 95616 USA. RP Nakafuji, DTY (reprint author), Lawrence Livermore Natl Lab, New Technol Engn Div, POB 808,L-644, Livermore, CA 94551 USA. RI Smith, Rosemary/H-7359-2015; Collins, Scott/A-5806-2016 OI Smith, Rosemary/0000-0001-8483-6777; Collins, Scott/0000-0003-0204-5109 NR 27 TC 46 Z9 47 U1 2 U2 12 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 282 EP 289 DI 10.1115/1.1410110 PG 8 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900008 ER PT J AU Manuel, L Veers, PS Winterstein, SR AF Manuel, L Veers, PS Winterstein, SR TI Parametric models for estimating wind turbine fatigue loads for design SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB International standards for wind turbine certification depend on finding long-term fatigue load distributions that are conservative with respect to the state of knowledge for a given system Statistical models of loads for fatigue application are described and demonstrated using flap and edge blade-bending data front a commercial turbine in complex terrain. Distributions of rainflow-counted range data for each ten-minute segment are characterized by parameters related to their first three statistical moments (mean, coefficient of variation, and skewness). Quadratic Weibull distribution functions based on these three moments are shown to match the measured load distributions if the non-damaging low-amplitude ranges are first eliminated. The moments are mapped to the wind conditions with a two-dimensional regression over ten-minute average wind speed and turbulence intensity. With this mapping, the short-term distribution of ranges is known for any combination of average wind speed and turbulence intensity. The long-term distribution of ranges is determined by integrating over the annual distribution of input conditions. First, we study long-term loads derived by integration over wind speed distribution alone, using standard-specified turbulence levels. Next, we perform this integration over both wind speed and turbulence distribution for the example site. Results are compared between standard-driven and site-driven load estimates. Finally, using statistics based on the regression of the statistical moments over the input conditions, the uncertainty (due to the limited data set) in the long-term load distribution is represented by 95% confidence bounds on predicted loads. C1 Univ Texas, Dept Civil Engn, Austin, TX 78712 USA. Sandia Natl Labs, Wind Energy Technol Dept, Albuquerque, NM 87185 USA. Stanford Univ, Dept Civil & Environm Engn, Stanford, CA 94305 USA. RP Manuel, L (reprint author), Univ Texas, Dept Civil Engn, Austin, TX 78712 USA. RI Manuel, Lance/J-7884-2012 OI Manuel, Lance/0000-0002-0602-3014 NR 11 TC 11 Z9 11 U1 0 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 346 EP 355 DI 10.1115/1.1409555 PG 10 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900017 ER PT J AU Bir, GS AF Bir, GS TI Computerized method for preliminary structural design of composite wind turbine blades SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB A computerized method has been developed to aid preliminary design of composite wind turbine blades. The method allows for arbitrary specification of the chord, twist, and airfoil geometry along the blade and an arbitrary number of shear webs. Given the blade external geometry description and its design load distribution, the Fortran code uses ultimate-strength and buckling-resistance criteria to compute the design thickness of load-bearing composite laminates. The code also includes an analysis option to obtain blade properties if a composite laminates schedule is prescribed. These properties include bending stiffness, torsion stiffness, mass, moments of inertia, elastic-axis offset, and center-of-mass offset along the blade. Nonstructural materials-gelcoat, nexus, and bonding adhesive-are also included for computation of mass. This paper describes the assumed structural layout of composite laminates within the blade, the design approach, and the computational process. Finally, an example illustrates the application of the code to the preliminary design of a hypothetical blade and computation of its structural properties. C1 Natl Renewable Energy Lab, Natl Wind Technol Ctr, Golden, CO 80401 USA. RP Bir, GS (reprint author), Natl Renewable Energy Lab, Natl Wind Technol Ctr, 1617 Cole Blvd, Golden, CO 80401 USA. NR 8 TC 15 Z9 18 U1 1 U2 5 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 2001 VL 123 IS 4 BP 372 EP 381 DI 10.1115/1.1413217 PG 10 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 494WM UT WOS:000172308900020 ER PT J AU Rai, D Xia, YX Hess, NJ Strachan, DM McGrail, BP AF Rai, D Xia, YX Hess, NJ Strachan, DM McGrail, BP TI Hydroxo and chloro complexes/ion interactions of Hf4+ and the solubility product of HfO2(am) SO JOURNAL OF SOLUTION CHEMISTRY LA English DT Article DE solubility; hafnium complexes; thermodynamic data; solubility product; HfO2(am); hydroxide complexes; chloride complexes; Pitzer model; ion-interaction parameters ID AQUEOUS K+-HCO3--CO32--OH--H2O SYSTEM; THERMODYNAMIC MODEL; HYDROLYSIS CONSTANTS; NATURAL-WATERS; PREDICTION; PLUTONIUM; TH(IV) AB The solubility of HfO2(am) was determined at different equilibration periods from the over- and undersaturation directions, in very acidic to basic solutions (0. 1 m HCl to 3.2 m NaOH), and in NaCl solutions ranging in concentrations from very dilute to as high as 5.59 m and in a pC(H)+ range from I to 4 to obtain reliable thermodynamic data for the Hf4+-Cl--Na+-H+-OH-- H2O system. The studies indicate that equilibrium is reached rapidly (<5 days) and that HfO2(am) solubility shows amphoteric behavior. The solubility data obtained in this study, along with the data reported in the literature, at NaOH molalities as high as 21.7 m were interpreted using the ion-interaction model of Pitzer. The log K-0 for the solubility of HfO2(am) [HfO2(am) + 2H(2)Oreversible arrow Hf4+ + 4OH(-)] was determined to be -55.1 +/- 0.7. The log K-0 values for the formation of HfOH3+, Hf(OH)(4)(0), Hf(OH)(5)(-), and Hf(OH)(6)(2-) according to the reaction (Hf4+ + xOH(-) reversible arrow Hf(OH)(x)(4-x)) were determined to be 13.8, <44.8, 49.7 +/- 0.2, and 51.2 +/- 0.2, respectively. The thermodynamic model developed in this study is valid for a wide range of conditions (as high as 0.1 m HCl, 21.7 m NaOH, and 5.59 in NaCl. The binary ion-interaction parameters for Hf4+-Cl-, HfOH3+-Cl-, and Hf(OH)(6)(2-)-Na+ were determined in this study to accurately define the observed solubility behavior of hafnium in various systems. C1 Pacific NW Natl Lab, Actmide & Trace Met Geochem Grp, Richland, WA 99352 USA. RP Rai, D (reprint author), Pacific NW Natl Lab, Actmide & Trace Met Geochem Grp, Richland, WA 99352 USA. OI Hess, Nancy/0000-0002-8930-9500 NR 43 TC 13 Z9 13 U1 1 U2 11 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0095-9782 J9 J SOLUTION CHEM JI J. Solut. Chem. PD NOV PY 2001 VL 30 IS 11 BP 949 EP 967 DI 10.1023/A:1013337925441 PG 19 WC Chemistry, Physical SC Chemistry GA 514HP UT WOS:000173433400001 ER PT J AU Hasnain, SS Kamitsubo, H Mills, DM AF Hasnain, SS Kamitsubo, H Mills, DM TI New synchrotron radiation sources and the next-generation light sources SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Editorial Material C1 SERC, Daresbury Lab, CLRC, Synchrotron Radiat Dept, Warrington WA4 4AD, Cheshire, England. JASRI, SPring 8, Mikazuki, Hyogo 6785198, Japan. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Hasnain, SS (reprint author), SERC, Daresbury Lab, CLRC, Synchrotron Radiat Dept, Warrington WA4 4AD, Cheshire, England. NR 0 TC 4 Z9 4 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD NOV PY 2001 VL 8 BP 1171 EP 1171 DI 10.1107/S0909049501015989 PN 6 PG 1 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 485JH UT WOS:000171750900001 PM 11679767 ER PT J AU Watson, JG Chow, JC Edgerton, SA AF Watson, JG Chow, JC Edgerton, SA TI A special issue from the NARSTO Symposium on Tropospheric Aerosols SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Editorial Material C1 Univ Nevada, Desert Res Inst, Reno, NV 89506 USA. Pacific NW Natl Lab, Washington, DC USA. RP Watson, JG (reprint author), Univ Nevada, Desert Res Inst, Reno, NV 89506 USA. RI Watson, John/E-6869-2010 OI Watson, John/0000-0002-1752-6899 NR 12 TC 0 Z9 0 U1 1 U2 1 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA ONE GATEWAY CENTER, THIRD FL, PITTSBURGH, PA 15222 USA SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD NOV PY 2001 VL 51 IS 11 BP 1506 EP 1507 PG 2 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 491ZL UT WOS:000172140400001 PM 11720097 ER PT J AU Morissette, SL Lewis, JA Clem, PG Cesarano, J Dimos, DB AF Morissette, SL Lewis, JA Clem, PG Cesarano, J Dimos, DB TI Direct-write fabrication of Pb(Nb,Zr,Ti)O(3 d)evices: Influence of paste rheology on print morphology and component properties SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID PZT THICK-FILMS; CERAMICS; INDUSTRY AB Lead niobium zirconate titanate (PNZT) pastes with tailored rheological properties have been developed for direct-write fabrication of thick-film capacitor elements in highly integrated, multifunctional electroceramic devices. Such pastes exhibited pseudoplastic behavior with a low shear apparent viscosity of roughly 1 x 10(6) cP. On aging, the degree of shear thinning and the low shear apparent viscosity decreased. Pastes prepared from as-received powders attained printable, steady-state viscosities of similar to2 x 10(5) cP after 50 days of aging. In contrast, pastes prepared from dispersant-coated powders showed no measurable rheological changes after 1 day of aging. Square elements were patterned on dense alumina substrates or Teflon sheets. Leveling behavior as a function of time for single line prints, and the resulting surface topographies of dried PNZT films were measured by laser profilometry. PNZT layers sintered at varying temperatures between 950 degrees and 1050 degreesC for 5 h in either air or a lead-rich atmosphere yielded porous microstructures as revealed by scanning electron microscopy (SEM). Such layers exhibited dielectric constants (K) of 1400-1570 at 1 kHz with dissipation factors (D) of less than 4.1%. C1 Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Univ Illinois, Dept Mat Sci & Engn, 1304 W Green St, Urbana, IL 61801 USA. NR 37 TC 43 Z9 44 U1 3 U2 24 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0002-7820 EI 1551-2916 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD NOV PY 2001 VL 84 IS 11 BP 2462 EP 2468 PG 7 WC Materials Science, Ceramics SC Materials Science GA 491YE UT WOS:000172137000001 ER PT J AU Zheng, J Akinc, M AF Zheng, J Akinc, M TI Green state joining of SiC without applied pressure SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID SILICON-CARBIDE; POLYCARBOSILANE; CERAMICS AB External pressure (uniaxial or isostatic) is usually necessary to form a thin and defect-free joint in green state joining of Sic ceramics. A successful method of joining Sic in the green state using a liquid polymer precursor, allylhydridopolycarbosilane (AHPCS), without applied pressure, is described. The thermal decomposition behavior of the polymer was examined, and defect formation during joint evolution was investigated by interrupting the heat treatment at various stages. Cracks and pores were observed in the joints formed by pure AHPCS during the pyrolysis of the polymer precursor. Adding Sic powder to the joining paste eliminated defect formation. Optimum Sic loading in the paste was determined to be in the range of 25-35 vol%. Joints formed by AHPCS + (SiC + 5 wt% B) paste were essentially indistinguishable from the matrix and had an average strength of 323 MPa, comparable to that of the control sample. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Zheng, J (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 17 TC 28 Z9 29 U1 4 U2 14 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD NOV PY 2001 VL 84 IS 11 BP 2479 EP 2483 PG 5 WC Materials Science, Ceramics SC Materials Science GA 491YE UT WOS:000172137000004 ER PT J AU Lance, MJ Vogel, EM Reith, LA Cannon, WR AF Lance, MJ Vogel, EM Reith, LA Cannon, WR TI Low-temperature aging of zirconia ferrules for optical connectors SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID STABILIZED ZIRCONIA; FIBER CONNECTORS; TRANSFORMATION; DEGRADATION; MECHANISM; CERAMICS; ENDS AB Zirconia ferrules for optical connectors were examined after aging at 85 degreesC and 95% relative humidity. Two degradation mechanisms were the roughening and the deformation of the zirconia ferrule surface. Raman microscopy revealed that this relatively low-temperature degradation of zirconia ferrules is caused by the tetragonal to monoclinic transformation of zirconia, and is accelerated by stress relief during polishing. The surface upheavals associated with low-temperature aging may significantly degrade the performance of optical connectors over time. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Rutgers Univ, Dept Ceram & Mat Engn, Piscataway, NJ 08854 USA. BELLCORE, Morristown, NJ 07960 USA. RP Lance, MJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Lance, Michael/I-8417-2016 OI Lance, Michael/0000-0001-5167-5452 NR 18 TC 16 Z9 17 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD NOV PY 2001 VL 84 IS 11 BP 2731 EP 2733 PG 3 WC Materials Science, Ceramics SC Materials Science GA 491YE UT WOS:000172137000050 ER PT J AU Gorshkov, MV Masselon, CD Anderson, GA Udseth, HR Harkewicz, R Smith, RD AF Gorshkov, MV Masselon, CD Anderson, GA Udseth, HR Harkewicz, R Smith, RD TI A dynamic ion cooling technique for FTICR mass spectrometry SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID CYCLOTRON RESONANCE SPECTROSCOPY; PENNING TRAP; TRANSFORM; ELECTRON; PLASMA AB A fast dynamic ion cooling technique based upon the adiabatic invariant phenomenon for Fourier transform ion cyclotron resonance mass spectrometry (FTICR) is presented. The method cools ions in the FTICR trap more efficiently, within a few hundred milliseconds without the use of a buffer gas, and results in a substantial signal enhancement. All performance aspects of the FTICR spectrum, e.g., peak intensities, mass resolution, and mass accuracy, improve significantly compared with cooling based on ion-ion interactions. The method may be useful in biological applications of FTICR, such as in proteomic studies involving extended on-line liquid chromatography (LC) separations, in which both the duty cycle and mass accuracy are crucially important. (C) 2001 American Society for Mass Spectrometry. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, MS K8-98,POB 999,902 Battelle Blvd, Richland, WA 99352 USA. RI Gorshkov, Mikhail/E-8522-2010; Masselon, Christophe/A-2340-2010; Smith, Richard/J-3664-2012; Gorshkov, Mikhail/N-4984-2013 OI Smith, Richard/0000-0002-2381-2349; Gorshkov, Mikhail/0000-0001-9572-3452 FU NCRR NIH HHS [RR12365] NR 17 TC 10 Z9 10 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD NOV PY 2001 VL 12 IS 11 BP 1169 EP 1173 DI 10.1016/S1044-0305(01)00306-3 PG 5 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 490XN UT WOS:000172079100004 PM 11720391 ER PT J AU Springer, TE Rockward, T Zawodzinksi, TA Gottesfeld, S AF Springer, TE Rockward, T Zawodzinksi, TA Gottesfeld, S TI Model for polymer electrolyte fuel cell operation on reformate feed effects of CO, H-2 dilution, and high fuel utilization (vol 148, pg A11, 2001) SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Correction C1 Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Springer, TE (reprint author), Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, POB 1663, Los Alamos, NM 87545 USA. NR 1 TC 1 Z9 1 U1 0 U2 7 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD NOV PY 2001 VL 148 IS 11 BP I9 EP I9 PG 1 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 483TZ UT WOS:000171653100057 ER PT J AU Biswas, R Ozbay, E Temelkuran, B Bayindir, M Sigalas, MM Ho, KM AF Biswas, R Ozbay, E Temelkuran, B Bayindir, M Sigalas, MM Ho, KM TI Exceptionally directional sources with photonic-bandgap crystals SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID ANTENNA; GAP AB Three-dimensional photonic-bandgap crystals are used to design and fabricate uniquely directional sources and receivers. By utilizing the resonances of a Fabry-Perot cavity formed with photonic-bandgap crystals, we were able to create exceptionally directional sources by placing the sources within such a cavity. Very good agreement between finite-difference time-domain calculations and the experiment is obtained. Radiation patterns with half-power beam widths of less than 12 degrees were obtained. (C) 2001 Optical Society of America. C1 Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ctr Microelect Res, Ames, IA 50011 USA. Bilkent Univ, Dept Phys, TR-06533 Bilkent, Turkey. Agilent Technol Inc, Palo Alto, CA 94306 USA. Iowa State Univ Sci & Technol, Ames Lab, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ctr Microelect Res, Ames, IA 50011 USA. RP Biswas, R (reprint author), Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. RI Ozbay, Ekmel/B-9495-2008 NR 19 TC 55 Z9 56 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD NOV PY 2001 VL 18 IS 11 BP 1684 EP 1689 DI 10.1364/JOSAB.18.001684 PG 6 WC Optics SC Optics GA 491CE UT WOS:000172089800018 ER PT J AU Peters, AM Nastasi, M AF Peters, AM Nastasi, M TI Plasma immersion ion cleaning of oxidized steel surfaces using hexafluoroethane and argon plasmas SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article ID THIN-FILM ADHESION; SHEET PLASMA; IMPLANTATION; DISCHARGES; CF4 AB For many years it has been known that cleaning of substrates using plasma techniques prior to physical vapor deposition processes can significantly improve coating adhesion. This article investigates the use of hexafluoroethane and argon plasmas in a pulsed glow discharge cleaning process. Applied voltages varied from - 2 to - 8 kV with a constant chamber pressure of 10 mTorr and etching times ranged from 15 to 120 min. Results indicate that in most cases, the hexafluoroethane plasmas removed 25% more oxygen atoms than the argon plasmas at similar applied voltages. Most of the oxygen removal was observed within the first 15 min with diminishing removal with increased cleaning time beyond 30 min. Plasma analysis revealed that the principal plasma specie was CF3 and reaction products for oxygen removal were carbon dioxide and carbon monoxide. The hexafluoroethane plasmas were determined to clean through a chemically enhanced sputtering while argon plasmas cleaned by physical sputtering only. (C) 2001 American Vacuum Society. C1 Los Alamos Natl Lab, Div Mat Sci & Technol MST8, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Mat Sci & Technol MST8, Los Alamos, NM 87545 USA. EM ampeters@lanl.gov NR 27 TC 4 Z9 4 U1 0 U2 4 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 EI 1520-8559 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD NOV-DEC PY 2001 VL 19 IS 6 BP 2773 EP 2778 DI 10.1116/1.1403720 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 497QE UT WOS:000172466300007 ER PT J AU Keil, D Anderson, E AF Keil, D Anderson, E TI Characterization of reactive ion etch lag scaling SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID FEATURES AB Recent advances in ultralarge -scale integration have typically depended on reductions in etched feature size. This has motivated efforts to find etch processes that will precisely etch increasingly smaller features while retaining the ability to etch larger features. As feature sizes push below 0.25 mum, reactive ion etch (RIE) lacy control becomes increasingly important. Knowing how RIE lag scales with feature size for a given process aids in determining if that process must be discarded and a new one developed. In those situations where a process cannot be discarded, an understanding of RIE lac, scaling aids in predicting fabrication difficulties for a given device design. Using a minimal set of initial assumptions, it is shown that a relationship can be derived which relates etch rate to the time development of the feature aspect ratio. It is then shown that this relationship can be used to derive an expression for the etch depth as a function of time and feature size. The assumptions made are justified by phenomenological observation rather than by an assumed mechanism. This approach enhances the generality of the results obtained, thus making them useful for a variety of practical etch engineering applications. (C) 2001 American Vacuum Society. C1 Lam Res Corp, Fremont, CA 94538 USA. Lawrence Berkeley Labs, Berkeley, CA 94720 USA. RP Keil, D (reprint author), Lam Res Corp, 4400 Cushing Pkwy, Fremont, CA 94538 USA. NR 14 TC 25 Z9 25 U1 0 U2 3 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE,, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 2001 VL 19 IS 6 BP 2082 EP 2088 DI 10.1116/1.1414116 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 509PY UT WOS:000173159900013 ER PT J AU Chapman, HN Ray-Chaudhuri, AK Tichenor, DA Replogle, WC Stulen, RH Kubiak, GD Rockett, PD Klebanoff, LE O'Connell, D Leung, AH Jefferson, KL Wronosky, JB Taylor, JS Hale, LC Blaedel, K Spiller, EA Sommargren, GE Folta, JA Sweeney, DW Gullikson, EM Naulleau, P Goldberg, KA Bokor, J Attwood, DT Mickan, U Hanzen, R Panning, E Yan, PY Gwyn, CW Lee, SH AF Chapman, HN Ray-Chaudhuri, AK Tichenor, DA Replogle, WC Stulen, RH Kubiak, GD Rockett, PD Klebanoff, LE O'Connell, D Leung, AH Jefferson, KL Wronosky, JB Taylor, JS Hale, LC Blaedel, K Spiller, EA Sommargren, GE Folta, JA Sweeney, DW Gullikson, EM Naulleau, P Goldberg, KA Bokor, J Attwood, DT Mickan, U Hanzen, R Panning, E Yan, PY Gwyn, CW Lee, SH TI First lithographic results from the extreme ultraviolet Engineering Test Stand SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 45th International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication CY MAY 29-JUN 01, 2001 CL WASHINGTON, D.C. SP Amer Vacuum Soc, IEEE Electron Device Soc, Opt Soc Amer AB The extreme ultraviolet (EUV) Engineering Test Stand (ETS) is a step-and-scan lithography tool that operates at a wavelength of 13.4 nm. It has been developed to demonstrate full-field EUV imaging and acquire system learning for equipment manufacturers to develop commercial tools. The initial integration of the tool is being carried out using a developmental set of projection optics, while a second, higher-quality, projection optics is being assembled and characterized in a parallel effort. We present here the first lithographic results from the ETS, which include both static and scanned resist images of 100 nm dense and isolated features throughout the ring field of the projection optics. Accurate lithographic models have been developed and compared with the experimental results. (C) 2001 American Vacuum Society. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. ASML, NL-5503 LA Veldhoven, Netherlands. Intel Corp, Santa Clara, CA 95052 USA. RP Chapman, HN (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. RI Chapman, Henry/G-2153-2010; Bokor, Jeffrey/A-2683-2011 OI Chapman, Henry/0000-0002-4655-1743; NR 7 TC 43 Z9 43 U1 1 U2 2 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE,, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 2001 VL 19 IS 6 BP 2389 EP 2395 DI 10.1116/1.1414017 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 509PY UT WOS:000173159900065 ER PT J AU Naulleau, P Goldberg, KA Anderson, EH Batson, P Denham, PE Jackson, KH Gullikson, EM Rekawa, S Bokor, J AF Naulleau, P Goldberg, KA Anderson, EH Batson, P Denham, PE Jackson, KH Gullikson, EM Rekawa, S Bokor, J TI At-wavelength characterization of the extreme ultraviolet Engineering Test Stand Set-2 optic SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 45th International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication CY MAY 29-JUN 01, 2001 CL WASHINGTON, D.C. SP Amer Vacuum Soc, IEEE Electron Device Soc, Opt Soc Amer ID POINT-DIFFRACTION INTERFEROMETER; LITHOGRAPHY; RADIATION AB At-wavelength interferometric characterization of a new 4x-reduction lithographic-quality extreme ultraviolet (EUV) optical system is described. This state-of-the-art projection optic was fabricated for installation in the EUV lithography Engineering Test Stand (ETS) and is referred to as the ETS Set-2 optic. EUV characterization of the Set-2 optic is performed using the EUV phase-shifting point diffraction interferometer (PS/PDI) installed on an undulator beamline at Lawrence Berkeley National Laboratory's Advanced Light Source. This is the same interferometer previously used for the at-wavelength characterization and alignment of the ETS Set-1 optic. In addition to the PS/PDI-based full-field wave front characterization, we also present wave front measurements performed with lateral shearing interferometry, the chromatic dependence of the wave front error, and the system-level pupil-dependent spectral-bandpass characteristics of the optic; the latter two properties are only measurable using at-wavelength interferometry. (C) 2001 American Vacuum Society. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Univ Calif Berkeley, EECS Dept, Berkeley, CA 94720 USA. RP Naulleau, P (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RI Bokor, Jeffrey/A-2683-2011 NR 20 TC 17 Z9 17 U1 0 U2 0 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE,, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 2001 VL 19 IS 6 BP 2396 EP 2400 DI 10.1116/1.1421545 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 509PY UT WOS:000173159900066 ER PT J AU Yi, MS Haga, T Walton, C Bokor, J AF Yi, MS Haga, T Walton, C Bokor, J TI High sensitivity actinic detection of native defects on extreme ultraviolet lithography mask blanks SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 45th International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication CY MAY 29-JUN 01, 2001 CL WASHINGTON, D.C. SP Amer Vacuum Soc, IEEE Electron Device Soc, Opt Soc Amer AB We present recent experimental results of actinic extreme ultraviolet lithography mask blank defect inspection. The detection sensitivity of the current actinic inspection system is predicted to be able to reach approximately 30 nm in cross correlation experiments done with commercial visible-light, scanning electron microscopy (SEM), and atomic force microscopy (AFM) inspection tools. Random, native defects identified using the visible-light tool were scanned by the actinic tool and the scattering characteristics were compared. SEM and AFM characterization of selected defects were also performed for physical measurement. We found a defect whose size was as small as 60 nm and AFM analysis showed that this defect was a 3 nm high substrate defect that was smoothed-out by the multilayer coating. (C) 2001 American Vacuum Society. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. NTT, Telecommun Energy Labs, Atsugi, Kanagawa 2430198, Japan. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, EECS Dept, Berkeley, CA 94720 USA. RP Yi, MS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RI Haga, Tsuneyuki/C-3372-2015; Bokor, Jeffrey/A-2683-2011 NR 7 TC 17 Z9 17 U1 0 U2 1 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE,, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 2001 VL 19 IS 6 BP 2401 EP 2405 DI 10.1116/1.1410088 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 509PY UT WOS:000173159900067 ER PT J AU Anderson, EH Olynick, DL Chao, WL Harteneck, B Veklerov, E AF Anderson, EH Olynick, DL Chao, WL Harteneck, B Veklerov, E TI Influence of sub-100 nm scattering on high-energy electron beam lithography SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 45th International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication CY MAY 29-JUN 01, 2001 CL WASHINGTON, D.C. SP Amer Vacuum Soc, IEEE Electron Device Soc, Opt Soc Amer AB Electron beam lithography tools have evolved in the direction of higher beam energy in order to achieve high-resolution, fine feature definition. As the beam energy is increased, the "forward" scattering is reduced and the "backscatter" range is increased. Over the years, tools became available data 20 then 50 kV, and now 100 kV operation is common. Operation at higher voltages has several advantages, such as better resolution and process latitude due to reduced forward scattering, and a few disadvantages such as higher dose requirements, substrate heating, and lower contrast for backscatter electron alignment and calibration signals (due to reduced primary electron backscattering generation in thin film). The backscatter range for 100 kV on silicon is about 27 mum compared to 8 mum at 50 kV resulting in different strategies for efficient proximity correction. However, even at 100 kV, scattering in an intermediate range is observed and must be taken into account in order to achieve good linewidth control at the highest resolution. Measurements of the scattering range for both 50 and 100 kV have been made using the point exposure distribution measurement technique [S. A. Rishton and D. P. Kern, J. Vac. Sci. Technol. B 5, 135 (1987)]. For comparison, measurements taken on the same wafer at different voltages show that 50 and 100 kV scattering range functions overlap, after normalizing for the different resist sensitivity, at length scales below 0.5 mum, suggesting a common mechanism, which is independent of the initial electron energy. For thin resists, this suggests that the significant resolution difference between 50 and 100 kV lithography is limited to the "forward" scattering effect as the incident electrons traverse the resist. Extrapolating the scattering function to the approximate beam diameter of 10 nm allows an impulse response function to be numerically determined. The convolution of this function gives reasonably good agreement with dose versus linewidth measurements. (C) 2001 American Vacuum Society. C1 EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Anderson, EH (reprint author), EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 4 TC 21 Z9 21 U1 0 U2 1 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE,, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 2001 VL 19 IS 6 BP 2504 EP 2507 DI 10.1116/1.1415506 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 509PY UT WOS:000173159900086 ER PT J AU Schmid, P Rose, H AF Schmid, P Rose, H TI Outline of a variable-axis lens with arbitrary shift of the axis in one direction SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 45th International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication CY MAY 29-JUN 01, 2001 CL WASHINGTON, D.C. SP Amer Vacuum Soc, IEEE Electron Device Soc, Opt Soc Amer ID ELECTRON-BEAM LITHOGRAPHY; GLASS PHOTOCATHODES; SEMICONDUCTOR AB A sophisticated electrostatic "variable-axis lens" is proposed which allows an arbitrary shift of the axis in one direction. For this purpose we employ a periodic arrangement of the electrodes in a direction perpendicular to the initial axis. The excitations of the electrodes are chosen in such a way that stigmatic imaging is conserved when the axis is shifted. The purely electric field components Guarantee a fast dynamic shift of both the axis and the focusing field. Owing to the translational symmetry of the arrangement, the system enables much larger displacements of the axis than the conventional "variable-axis lens." Moreover, this concept allows the simultaneous shift of many spatially separated lenses. Since the multiple beam system avoids a common crossover of the individual beams, large total currents can be employed. (C) 2001 American Vacuum Society. C1 Tech Univ Darmstadt, Inst Appl Phys, D-64289 Darmstadt, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Schmid, P (reprint author), Tech Univ Darmstadt, Inst Appl Phys, Hsch Str 6, D-64289 Darmstadt, Germany. NR 15 TC 2 Z9 2 U1 0 U2 3 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE,, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 2001 VL 19 IS 6 BP 2555 EP 2565 DI 10.1116/1.1418408 PG 11 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 509PY UT WOS:000173159900098 ER PT J AU Guillorn, MA Melechko, AV Merkulov, VI Ellis, ED Simpson, ML Baylor, LR Bordonaro, GJ AF Guillorn, MA Melechko, AV Merkulov, VI Ellis, ED Simpson, ML Baylor, LR Bordonaro, GJ TI Microfabricated field emission devices using carbon nanofibers as cathode elements SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 45th International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication CY MAY 29-JUN 01, 2001 CL WASHINGTON, D.C. SP Amer Vacuum Soc, IEEE Electron Device Soc, Opt Soc Amer ID NANOTUBES AB The digital electrostatic electron beam array lithography concept under development at the Oak Ridge National Laboratory proposes performing direct write electron beam lithography with a massively parallel array of electron emitters operating simultaneously within a digitally programmable microfabricated field emitter array (FEA). Recently we have concentrated our research efforts on the field emission (FE) properties of deterministically grown vertically aligned carbon nanofibers (VACNFs). We have measured the FE properties of isolated VACNFs using a moveable current probe and found that they have low FE turn-on fields and can achieve stable emission for extended periods of time in moderate vacuum. In order to use the VACNF in microfabricated FEA devices we have subjected them to a variety of processing phenomenon including reactive ion etching and plasma enhanced chemical vapor deposition, and found them to be quite robust. Using these processes we have fabricated operational gated cathode structures with sin-le VACNFs cathodes. The issues involved in this fabrication process and the performance of these devices are discussed. (C) 2001 American Vacuum Society. C1 Oak Ridge Natl Lab, Mol Scale Engn & Nanoscale Technol Res Grp, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37831 USA. Cornell Univ, Cornell Nanofabricat Facil, Ithaca, NY 14853 USA. RP Guillorn, MA (reprint author), Oak Ridge Natl Lab, Mol Scale Engn & Nanoscale Technol Res Grp, Oak Ridge, TN 37831 USA. RI Melechko, Anatoli/B-8820-2008; Simpson, Michael/A-8410-2011 OI Simpson, Michael/0000-0002-3933-3457 NR 12 TC 33 Z9 33 U1 0 U2 14 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE,, MELVILLE, NY 11747-4502 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD NOV-DEC PY 2001 VL 19 IS 6 BP 2598 EP 2601 DI 10.1116/1.1420201 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 509PY UT WOS:000173159900104 ER EF